Influence of reversible obesity on eating behavior, blood glucose, and insulin in the rat.

Excessive food intake, resulting in extreme obesity, was induced in rats by electrical stimulation (three 30-min sessions per day for 3 wk) of the lateral hypothalamus (LH).  Outside the stimulation sessions no voluntary food intake occurred duringthese weeks.  In the subsequent recovery period, accurate records of spontaneous feeding were made.  Blood levels of glucose, insulin, and free fatty acids (FFA)were determined during the stimulation period as well as the recovery period.  Duringfeeding elicited by electrical stimulation of the LH in the obese phase, there was alarge increase in the glucose level.  The insulin level, very high in the intervals between the stimulation sessions, showed no change, a small decline, or a large decrease,respectively, during stimulation in the morning, the afternoon, or the night.  If food was withheld during stimulation, there was a large increase in the glucose level and alarge decrease in the insulin level.  The first spontaneous meal after the termination of stimulation was extremely postponed, viz, until the glucose and insulin levels returned to normal for the first time.  The insulin response to the first spontaneous mealwas exaggerated.  Although in the following period (about 10 days) a rapid decrease inbody weight occurred, food intake was only minimal.  The insulin level was high and the glucose levelsubnormal during that period.  The insulin and glucose levels were normal again only after recovery of normal body weight and food intake.  It is tentatively concluded that the regulation of body energy stores (body weight) is achieved through the control of food intake by circulating insulin and glucose levels.


Effects of hypothalamic stimulation on gluconeogenesis and glycolysis in rat liver.

Hypothalamic effects on gluconeogenesis and glycosis in rat liver were studied byelectrical stimulations of the ventromedial hypothalamic nucleus (LH) without disturbing the animal's behavior.  Stimulation of VMH caused a increase in the activity of phosphoenolpyruvate carboxykinase (PEPCK), a key gluconeogenic enzyme, and marked suppression of pyruvate kinase (PK), a key glycolytic enzyme, of the liver.  Stimulationof LH, on the other hand, resulted in a decrease in PEPCK activity but did not alterPK activity.  The maximal responses of these enzymes to hypothalamic stimulations were obtained after intermittent stimulations for 4 h.  Differential estimations of thetwo isozymes of liver PK (types L and M) were made using antibody against typeM PK.  The level of type M enzyme was not altered significantly on stimulation of either VMH or LH.  The content of type L enzyme greatly decreased on stimulation of VMH but was not affected by stimulation of LH.  The reciprical influences of VMH and LH on hepatic carbohydrate metabolism and their relation to neural-hormonal responses are discussed.


Comparative metabolism of tritiated water by macropodid marsupials.

The total body-water content (TBW) and rate of water turnover were measured usingtritiated water in five species of macropodod marsupials (kangaroos), which ranged in weight from 1 to 50 kg.  Animals fitted with rumen cannulas were used to estimate the time required for tritiated water to equilibrate within the body of large kangaroos.  In hydrated kangaroos this was 6 h, during the time 2.7% of the injected tritiated waterwas lost from the body.  During dehydration, the equilibrium time was extended to 10h. Values up to 78% of body weight were found for TBW in the larger species of kangaroo, and these values were similiar to those found for other ruminantlike mammals, particularly those with a low body-fat content.  The smaller macropodids had a TBW (about 60% of body weight) similiar to that of most laboratory mammals.  The rates of waterturnover of the macropodids were related to body weights by the expression 1/day = 0.09kg-0.80.  Macropodid marsupials have a daily water usage shich is about two-thirds ofthat found for eitherians and this may be related to the lower metabolic rate of marsupials.


Papillary muscle dynamics: in situ function and responses of the papillary muscle.

Experiments were designed to 1) study in situ changes in papillary muscle length and force during the cardiac cycle, 2) investigate the relationship between papillary muscle length and maximal ventricular pressure, 3) study the effect of both positive and negative inotropic intervention on this relationship.  A mercury gauge transduceror Walton-Brodie strain-gauge arch was sutured to the anterior papillary muscleand used to measure the extent of shortening or lengthening (deltaL) or force (APMF),.respectively.  The anterior papillary muscle showed rapid increase of length and forcewhile contracting during isovolumic contraction and reached peak systolic length at end-isovolumic contraction or during the early injection phase.  The papillary muscle was observed to shorten during the phases of ejection  and isovolumic relaxation.  It was concluded that changes in ventricular pressure during the cardiac cycle are associated with changes in papillary muscle length and force such that the resulting "lengthening contraction force" is appropiate for maintenance of normal atrioventricular valve function during isovolumic contraction.  There was an inverse relationship between deltaL and maximal ventricular pressure such that for each increment in peak ventricular pressure there was a decrease in deltaL.  The deltaL-force relationship was shifted upward and to the right by norepinephrine (NE) and isoproterenol and downward and to the left by occlusion of the posterior vena cava.  Phenylephrine had little or no effect on this relationship.


NE and ACh responses of intrapulmonary vessels from dog, swine, sheep, and man.

The effects of norepinephrine (NE) and acetylcholine (ACh) on isometric force generation were studied in isolated helical strips of intrapulmonary arteries (IPA) and veins (IPV) (3-5 mm diam) from lungs of dog, sheep, swine, and man.  Cummalative dose-effect relationships (10-minus8-10-minus 4 M) were determined.  All strips contracted in a dose-related fashion when exposed to NE but responses of sheep and swineIPV were weak.  Acetylcholine relaxed canine IPA and contracted human IPA, CANINEIPV, and sheep IPV in a dose-related manner.  Sheep IPA and swine IPA and IPV were unresponsive to ACh.  Human IPV were relaxed by ACh but this effect wasreversed at the highest concentration (10 minus 4 M) tested.  All vascular stripscontracted well in a potassium-rich (127 mM) bathing medium.  It is concluded thatintrapulmonary lobar vessels from man, dog, swine, and sheep are responsive to autonomicneurohormones but that quantitative as well as qualitative differences exist.


Enzyme secretion in the absense of zymogen granules.

Pure pancreatic juice was collected from the cannulated common bile duct of anesthetized rats after an overnight fast.  Digestive enzyme secretion was followed in these animals during and after the progressive degranulation of acinar cells produced by sequentially applied cholinergic stimuli.  The kinetics of degranulation, a progressive decrease in the number of zymogen granules in acinar cells, was estimated from the relative cell volume occupied by electron-opaque granules at various times using a random pointcount stereological technique to examine tissue sections.  Three hourly injections of methacholine chloride were sufficient to produce the almost complete disappearance of electron-opaque granules from secretory cells.  Greatly augmented enzyme secretion was still observed in their absence, 7-25 times greater than control values:  10-fold for protein output overall,  7-fold for trypsinogen, and  25-fold for chymotrypsinogen.  Secretion in the absence of zymogen granules is discussed relativeto exocytosis and three-compartment (intracellular storage, cytoplasm, and duct lumen)secretory models.


Renin secretion from rat renal cortical cell suspensions.

Renin secretion of rat renal cortical cell suspensions was studied as a functionof variations in the composition of the suspension media.  Renin secretion was determined by incubating samples of the suspension media with rat renin substrate and measuringthe angiotensin I generated by radioimmunoassay.  Increasing the medium sodium concentration (50-144 meq/liter) linearly decreased the rate of renin secretion.  This relationship was unaffected by adding ouabain (10 minus 3 M)  to the suspensions.  The addition of furosemide (from 10 minus 5 to 10 minus 3 M) stimulated renin secretion.  Considered with previous observations, these results suggest that renin secretionis controlled by some function of sodium on the lumenal boder of the macula densa cells.


Renal autoregulation: evidence for the transmural pressure hypothesis.

Autoregulation of glomerular filtration rate (GFR) was examined during uteral orarterial constriction in anesthetized dogs after renal denervation.  GFR was sustaineduntil ureteral pressure greater than 80 mmHg, provided renal arterial pressure exceeded 180 mmHg, but fell at ureteral pressure less than 54 mmHg when arterial pressure averaged 127 plus or minus 5 mmHg; renal blood rose as GFR declined.  Ethacrynic acid, saline, or mannitol infusion increased tubular pressure without reducing GFR,but during subsequent ureteral constriction GFR fell at uteral pressure less than 40mmHg.  During arterial constriction GFR was maintained at lower arterial pressures in hydropenic than in diuretic dogs.  Because of thisdifference in the range of autoregulation, saline infusion increased GFR more in hydropenic than in diuretic dogs except at high arterial pressure.  This response to reduced plasma oncotic pressure and the constancy of GFR over a wide range of proximal tubular and arterial pressure indicate constancy of thehydrostatic transmural pressure of glomerular capillaries.  Afferent arteriolar resistance is, in addition to a regulation by transmural pressure, perhaps controlled by vascular stretch receptors in the glomeruli.


Salt and water balance and renin activity in renal hypertension of rats.

In male Sprague-Dawley rats, renal artery constriction in the presence of an inact contralateral kidney induced sodium retention (for 2-3 wk), moderate potassium loss,elevation of blood volume (BV), and an increase in water turnover.  It is suggestedthat renal artery constriction activates the renin-angiotensin-aldosterone system, resulting in disordered regulation of salt and water balance  and in blood pressure (BP) elevation.  Subsequently, sodium balance was reestablished in one group of hypertensive rats.  The previously retained sodium was kept in the body, and BV and reninactivity remained elevated.  In a second group of animals, a malignant course of hypertension developed: BP surpassed a critical level of about 180 mmHg; sodium, potassium, and water were lost; BV declined; renin activity was further stimulated; and in the contralateral kidney malignant nephrosclerosis occurred.  It is assumed that pressure diuresis and natriuresis induce a vicious circle: the increasing renin activity may maintain or further increase BP level, therby inducing further salt and water loss, etc.; high BP levels and high renin activities induce vascular damage and deterioration of renal function.


Central cardiovascular dynamics of ducks.

Blood pressures and flows have been recorded from the heart and arterial arches of ducks in order to present a complete picture of central hemodynamics in an avian species.  An attempt has also been made to define the characteristics of the avian central circulation in terms of either "windkessel", or wave-transmission models.  Mean arterial pressure (143 plus or minus 2.2 mmHg) and cardiac output (219 plus or minus 7ml/kg per min) were high compared with those of similarly sized mammals, although therewas no evidence of elevated pulmonary pressures, perhaps because of the unusual structure of the avian lung.  Only 25% of the total systemic flow was distributed by the aorta, the remainder supplying the wing, flight muscles, and head via the brachiocephalic arteries.  The contours of central pressure and flow waves ressembled those recorded inmammal except that significant circulation impedance modulus graphs indicated that resistance to pulsatile flow fell sharply to a minimum of 1/30th the DC value at 9-12 Hz.  Flow led pressure at frequencies below 9-12Hz and pressure led flow at higherfrequencies.  Impedance modulus in the pulmonary circulation fell to one-half the DC value and remained constant over a wide range of frequencies with pressure and flow being in a phase at all frequencies.  Aortic pulse wave velocity varied with position inthe aorta as did the pressure pulse profile: these factors obviously limit the applicability of a windkessel model to the avian circulation.


Factors affecting thermogenic drinking in rats.

After as little as 6 h of exposure to cold air, drinking was induced in rats following transfer from air at 5 degreesC to air at 26 degreesC.  Drinking began within 15 min after transfer from the cold enviroment and lasted approximately 1 h.  The stimulus for initiation of drinking was most likely the temperature change resulting from the transfer, since an ambient temperature difference of 10 centigrade degrees or more was required to initiate a drinking response after transfer from air at 5 degreesC. Thermogenic drinking was not thwarted by  preventing access to water for either 1 or 2h following transfer to warm air, but either intragastric or intraperitoneal administration of a water load equal to 3% of body weight inhibited water intake following transfer.The characteristics of the drinking response following transfer than 5 to 26 degrees C were similiar to those observed following 24 h of dehydration at 26 degrees C.  Thus, the cold-exposed rat is relatively dehydrated compared with controls.


Escape from vasoconstriction in the gastric microcirculation.

Escape of splanchic resistance vessels from vasconstriction due to adrenergic stimulation has been attributed to increasing submucosal blood flow due to dilation of submucosal arteriovenous anastomes (shunts).  This postulate, as applied to the rat gastric microcirculation, was studied by in vivo microscopy.  Using an image-splittingTV microscope recording system, response of gastric submucosal arterioles (13-33 mum)to 3 min of left splanchnic nerve stimulation, norepinephrine superfision, and vasopressin superfission was measured.  All stimuli produced initial vasoconstriction. Escape occurred in all rats with nerve stimulation and norepinephrine, but in onlyone of five with vasopressin.  No shunts were seen.  The study demonstrates that thegastric submucosal arterioles exhibit an escape phenomenon, suggesting that "autoregulatory escape" in other splanchic beds also may be due to relaxation of constricted vessels and not to opening of shunts.


Longitudinal contractions in the duodenum: their fluid-mechanical function.

The hypothesis examined was that contractions of the longitudinal muscle layer occurin the duodenum which are independent of those of the circular muscle layer and that they induce flow of duodenal contents.  A segment of opossum duodenum isolated in vitro was marked and photographed during periods of longitudinal muscle contraction, when the circular muscle layer appeared inactive.  The prequency of longitudinal oscillation of the marked points was 20.5 cycles/min.  The longitudinal displacement wave spread caudad with an average velocity of 3.27 cm/s.  Frequency and velocity of electrical slow waves were determined in similiar duodenal segments.  Slow-wave frquencywas 18.9 cycles/min.  In a two-dimensional mechanical model, flow induced by simulatedlongitudinal muscle layer appear to be driven by the electrical slow waves of the duodenum.  They are capable of inducing a pattern of flow in which ocntents flow betweenthe core and the periphery of the intestinal conduit.


Epidermal thermal conductivity and stratum corneum hydration in cat footpad.

Epidermal thermal conductivity (k) was calculated for the cat footpad by measuringtransepidermal heat flux and temperature gradient (¿T) while changes in stratum corneum water content were produced by "internal hydration" (IH; eccrine sweat gland activity by nerve stimulation) or by "external hydration" (HH; exposure to air saturated with water vapor).  In some experiments, cutaneous vasoconstriction accompanying IH was prevented by an alpha-adrenergic receptor blocking agent, phenoxybenzamine (POB), 3.52 mg/kg iv.  For dry skin k=0.167 plus or minus 0.023 (SE) W.m (-1) degree C (-1).  With and without POB, IH produced 49.5% and 17.2% increases in k, respectively; HH after IH did not increase k more.  With POB, IH increased k more than did HH alone (49.5% and 15.5%, respectively) and at a higher rate (4.22 times 10 minus 3 and 0.63 times 10 minus 3 W.m minus 1.degree C minus 1. min minus 1, respectively.)  As k increased, usually deltaT decreased.  Increasing k and decreasing deltaT with skin hydration explain the phenominon that air temperature is felt to be lower the more humid a cold exposure, since the temperature of thermoreceptors at the dermoepidermal junction is closer to that of the skin surface when the corneum is hydrated than when it has a low water content.


Analysis of coronary vascular beta receptors in situ.

Observations were conducted in the isolated potassium-arrested dog heart to determine the direct vasodilator effects of adrenergic agonists and antagonists on the coronaryvascular beta receptors, independent of cardiac inotropic and chronotropic influences. Practocol (a selective beta-1-receptor antagonist) blocked coronary vasodilation activated by isoproternol (a combined beta-1-and beta-2-receptor agonist) only at the very high dose of 10-minus 3 M, whereas propranolol (a combined beta-1- and beta-2-receptor antagonist) blocked coronary vasodilation at 10-minus 7 to 10-minus 5 M.  Salbutamol (a selective beta-2-receptor agonist) was one-eighth as potent as isoproterenol in producing coronary vasodilation.  The potency ratio (1/8) is similiar to valuesreported for other beta receptors classified as type 2.  It is concluded that the coronary vasodilator beta receptors are type 2, similiar to those found in peripheral bloodvessels.


Changes in cortical impedance and EEG activity induced by profound hypotension.

Fourteen late juvenile monkeys were subjected to a single 30-min episodes of markedhypotension using an infusion of trimethaphan.  Afterward, blood pressure was rapidly restored to and maintained at preinsult levels with an intravenous drip of phenylephrine (.02 mg/ml).  The respiratory gas tensions and pH of the arterial blood weremaintained within normal limits at all times.  During the 30-min episodes, the cortical electrical impedence increased by a mean of 27% while the EEG frequencies and amplitudes decreased by 47 and 30%, respectively.  The impedance and EEG activity generally altered at the same time but inversely to one another, although, on restoration of blood pressure, the impedance recovered within minutes while the EEG activity returned to normal only after 1 h. The impedance values and EEG activity of those animals that eventually died began to diverge significantly from the values of theanimals that were to survive at about 2.5 h after restoration of blood pressure.


Hydraulic and oncotic pressure measurements in inner medulla of mammalian kidney.

The vasa recta are thought to play an important role in the transfer of water andsolutes within the renal medulla.  Hydraulic pressures were measured in vasa recta onthe surface of the exposed papilla in young Munich Wistar rats, and blood was collected from these microvessels for determination of total protein concentration and calculation of colloid oncotic pressure.  In descending vasa recta at the base of the exposed papilla, mean hydraulic pressure was 9.2 plus or minus 0.4 (SE) mmHg and plasma protein concentration averaged 7.1 plus or minus 0.4 g/100 ml.  Corresponding valuesin ascending vasa recta at the same level were 7.8 plus or minus 0.4 mmHg and 5.6 plusor minus 0.3 g/100 ml. respectively.  The protein concentrations correspond to calculated oncotic pressures of 26 and 18 mmHg in descending and ascending vasa recta, respectively.  We interpret these findings as evidence for net water uptake by the vasa recta in the renal inner medulla for which the driving forces are the transcapillary hydraulic and oncotic pressure differences.


Determinants of peritubular capillary fluid uptake in hydropenia and saline and plasma expansion.

Hydrostatic (HPc) and oncotic (phic) pressures within the peritubular capillary, tubular pressure (Pt), nephron filtration rate, and plasma flow, and proximal fractional and absolute reabsorption (APR) were measured in anesthetized rats during hydropenia and plasma and saline expansion.  Net interstitial pressure (phii-HPi) was estimated from subcapsular hydrostatic and oncotic pressures during saline expansion and these data were applied to a mathematical model of peritubular capillary fluid uptake to determine the profile of effective reabsorption pressure (ERP) with distance (x*) alongthe capillary and calculate the peritubular capillary permeability coefficient (LpAr).  ERPX* = (PHIC MINUS HPC)X* MINUS (PHII MINUS HPi) and APR = ERPX*LpAr. During saline expansion phii minus HPi was -12.1 plus or minus 0.8 mmHg and ERP,3.8 mm.  The LpAr was 0.07 nl/s per g KW per mmHg, and this value was applied to hypropenia and plasma expansion to determine ERP and phii minus HPi.  The phiiminus HPi was +6.0 and +5.0 mmHg, respectively, and ERP was 4.1 and 3.5 mmHg. Efective reabsorptive pressure remained positive along x* in all states, and phii minus HPi correlated best changes in phic and poorly with changes in efferent plasma flow.  The APR did not correlate with either calculated phii minus HPi or the transepithelial driving pressure, Pt + phii minus HPi.


In vivo measurement of brain glucose transport and metabolism employing glucose- -11C.

The radiopharmaceutical glucose--11C was used in vivo measurement of brain-glucose transport kinetics and metabolism in the rhesus monkey.  Radiotracer was injected intravenously as a bolus.  Radioactivity was continuously recorded from the head and from the arterial blood via an indwelling peripheral artery catheter for a collectionperiod of 2-3 min.  To correct the reading obtained from the head for radioactivitycontained in blood, a second intravenous injection of the vascular tracer -15O-labeled carboxyhemoglobin was used.  The method was tested in nine phencyclidine-anesthetized monkeys in which cerebral glucose metabolism (CMRGlc) was simultaneously measured by our method and by a standard method emplying the Fick principle.  A highlysignificant correlation was found between the two methods of measuring CMRGlc (r =0.929).  In addition, our model predicted a ratio of forward-to-reverse glucose flux across the blood-brain barrier (BBR) (1.37 plus or minus 0.23 SD), the brain-to-bloodglucose concentration ratio across the BBB (0.633 plus or minus 0.14), the relative tissue free-glucose space (17 plus or minus 7%), the brain free-glucose concentration (13.6plus or minus 8.5 mg/100 g of tissue), and the brain free-glucose turnover time (2.96 plus or minus 1.98 min).  author


Acute psychosis, increased water ingestion, and inappropriate antidiuretic hormone secretion.

The authors describe three postmenopausal women with agitated psychotic depression, increased water ingestion, and electrolyte values consistent with the syndrome of inappropriate antidiuretic hormone (ADH) secretion. They hypothesize that this clinical triad represents a syndrome reflecting underlying dysfunction of the hypothalamus and limbic system of the brain. The diagnosis of inappropriate ADH in one of the patients was directly confirmed by a recently developed serum radioimmunoassay.


Implications of the medical model and its alternatives.

The term "medical model" is often used as if it referred to a single, well-understood set of assumptions about psychiatric disorders. Actually, there are at least four different meanings that a person saying "emotional disorders are diseases" might intend to communicate. The models usually suggested as alternatives are addressed to one or another of these medical model implications. A distinction should be maintained between the virtues of these models as conceptual aids and their virtues and weakness as shapers of public opinion and professional practice.


Psychiatric consultations in a pediatric hospital.

The authors conducted a study of 30 hospitalized children who were referred for psychiatric consultation and 60 hospitalized children who were not. They studied the medical charts of these children and administered a questionnaire including a checklist of behavioral symptoms to their parents. More psychopathology was found in the children referred for consultation, but about 20 percent of the children not referred also showed a high degree of psychopathology. Factors found to be associated with referral for psychiatric consultation were older age, longer hospital stay, many previous hospitalizations, and ambiguous diagnoses.


Court-mandated treatment: dilemmas for hospital psychiatry.

The authors present clinical material to illustrate the special treatment and management problems posed by different types of mentally ill offenders; they suggest that court-mandated hospital treatment is often destructive and unrelated to the needs of the patient, the community, and the mental institution. The failure to create new kinds of institutions, combining modalities derived from the hospital and correctional systems, is traced to poor communication among the disciplines involved. The "mentally ill offender" is caught in the interplay of these systems and is consequently both their victim and victimizer.


Informed consent in voluntary mental hospital admissions.

The authors studied the amount of understanding that 100 mental hospital patients had a voluntary admission application they signed upon entering the hospital. Only 8 patients were rated as being completely informed of terms of the contract at the time of admission; 15 of 33 patients reinterviewed about 10 days after admission showed increased understanding. Minimal differences were found between 81 state hospital patients and 19 private hospital patients. The finding that few voluntary patients are fully informed to give consent to hospitalization poses a dilemma because of the trend to give personal responsibility to the patient.


Meditation and the prevention of alcohol abuse.

The authors surveyed the frequency of alcohol use in individuals identified as practitioners of Transcendental Meditation (N equals 126) and a matched control group (N equals 90). No control subjects reported discontinuation of beer and wine use; 40 percent of subjects who had meditated for more than 2 years reported discontinuation within the first 6 months. After 25-39 months of meditation, this figure increased to 60 percent. In addition, 54 percent of this group, versus 1 percent of the control group, had stopped drinking hard liquor. The authors suggest that meditation could be an effective preventive tool in the area of alcohol abuse.


A fire-setting epidemic in a state mental health center.

The authors describe a period in which 13 fires were set by 4 patients on an inpatient service of a state mental health center. Unlike previous patients reported in the literature, these individuals had no history of fire setting, although they did display several previously reported characteristics (e.g., primitive and impulsive personalities and absent fathers). The influence of institutional changes and conflict upon such disruptive patient behavior is emphasized; the authors suggest that efforts to deal with fire setting should recognize the total situation and include clear limit setting by the hospital administration.


Hopelessness and attempted suicide: a reconsideration.

The authors administered measures of depression, hopelessness, and strength of suicidal intent to a sample of 112 suicide attempters. The results for the 55 subjects diagnosed as depressive and admitted within 72 hours after their attempt were compared with results obtained by Minkoff and associates using comparable measures. Contrary to the findings of the earlier study, there was a lower correlation between hopelessness and intent than between depression and intent. The authors suggest that demographic differences between the two samples may provide explanations for this descrepancy, in the that they reflect the presence or absence of external societal supports that may influence the suicidogenic potential of hopelessness.


Steady-state protriptyline levels in an outpatient population.

The authors measured steady-state protriptylive levels in 12 outpatients undergoing treatment for depression. The steady-state level of protriptyline was surprisingly high compared with levels obtained when other tricyclic antidepressants were prescribed. This finding probably accounts for the effectiveness of protriptyline at low doses and its frequent side effects.


Oxprenolol in the treatment of anxiety due to environmental stress.

The author conducted two trial studies to evaluate the use of oxprenolol in the treatment of symptoms resulting from environmental stress. Results indicated that on a three-times-a-day regimen, 80 mg of oxprenolol was superior to 20 mg of oxprenolol and equally as effective as 5 mg of diazepam. The author discusses the benefit of beta-blocking drugs and points to the need for further studies.


Familial unipolar depressive illness: a pedigree study.

The author reports a study of five generations of a family in which several members had unipolar depression responsive to tricyclic medication. He concludes that genetic factors play an important role in this disorder and emphasizes the need for pharmacogenetic studies in psychiatry.


Epidemiologic studies of eosinophilic meningitis in southern Taiwan.

A study of the epidemiologic characteristics of 125 cases of eosinophilic meningitis or meningoencephalitis, probably caused by Angiostrongylus cantonensis, which occurred in southern Taiwan in 1968 and 1969 revealed a close association of the disease with the rainy season. In contrast to findings in other geographic areas, most such cases in this study occurred among children. A higher attack rate was observed among aborigines than among descendants of mainland Chinese. Most patients had eaten the giant African snail, Achatina fulica, prior to their illness and this mollusc was commonly found infected with third-stage larvae of A. cantonensis. However, in almost all instances the snail was eaten after it had been thoroughly cooked and examination of cooked snail meat revealed only dead larvae. It is suspected that patients became infected by inadvertently ingesting A. cantonensis larvae liberated when the snails were prepared for consumption.


Specificity and sensitivity of skin test reactions to extracts of Toxocara canis and Ascaris suum. I. Skin tests done on infected guinea pigs.

The specificity and sensitivity of adult and larval somatic antigens, and perienteric fluid of Toxocara canis and Ascaris suum were investigated by using intradermal skin tests in guinea pigs. These animals were infected with low doses (0.01, 0.1 or 1.0 egg/g) of these helminths. Toxocara larval antigen (TL) induced larger reactions in Toxocara-infected animals than did the other antigens, suggesting a superior sensitivity for this antigen. In addition, Ascaris perienteric fluid (AP) provoked skin responses in these animals of a magnitude similar to those induced by TL. The reciprocal relationship, i.e., comparable reactivity of AP and TL in Ascaris-infected animals, was not apparent. In general, Ascaris larval antigen and AP elicited larger intradermal reactions than other antigens in Ascaris-infected animals. The results of this study indicated no superiority of adult antigens in differentiating Ascaris and Toxocara infections.


Visceral larva migrans: Immunoglobulins, precipitating antibodies and detection of IgG and IgM antibodies against Ascaris antigen.

Serum samples from ten children with visceral larva migrans were evaluated by analysis of: immunoglobulin concentrations, precipitin reactions against Toxocara and Ascaris antigens and blood group substances, and IgM and IgG activity against Ascaris antigen by radioimmunoassay (RIA). The elevated concentrations of serum IgE and IgG and the positive precipitin reactions which occurred in some cases are an aid in diagnosis but were not consistently present. Serum IgM concentrations were elevated in all cases. IgM or IgG antibodies against Ascaris suum antigen were detected in all cases by a solid phase RIA technique. Radioimmunoassay techniques of this type may provide a superior method of diagnosis, particularly if used with serial serum samples which demonstrate changing levels of antibodies.


Studies on the role of the famiy unit in the transmission of trachoma.

Rates of trachoma infection of family members were compared for two groups of index cases; all were infants about 1 year old observed over a period of several months in a previous study. Group A infants were consistently infected with trachoma, and Group B infants were not infected with trachoma. On the average, 50% of Group A family members had active infection (as determined by trachoma inclusions in their conjunctival cells) and 80% of the siblings within 6 years of age to the index cases were infected. Only 9% of Group B family members had active trachoma, and 20% of the siblings within 6 years of age to the index case were infected. This study suggests intrafamilial spread of trachoma.


Neutralization of Sindbis virus by antisera to antigens of vector mosquitoes.

Sindbis virus harvested from infected cultures of Vero cells and from Aedes aegypti mosquitoes was used in neutralization tests with sera obtained from guinea pigs immunized with ground A. aegypti and from guinea pigs repetitively bitten by mosquitoes. Employing these antisera, more mosquito-propagated virus was neutralized than was virus grown in cultures of Vero cells. The neutralizing activity resided in the immune globulin fraction and may reflect the production of antibody to vector antigens on the viral envelope.


A case of expectoration of Gnathostoma spinigerum in Thailand.

A living adult male Gnathostoma spinigerum was coughed up by a 33-year-old Thai married woman. The expectorated worm may have emerged from the pharynx. Pork is a possible source of infection in this case. The significant symptoms of her illness were migratory joint pain, chest pain, palpitation, and itchy throat, progressively. She has never had swellings.


Parasitic infection of man on Kar Kar Island, New Guinea.

The prevalence of protozoan and helminth parasites of the intestinal tract in a Papua New Guinea island with a population of 16,800 was assessed by surveys of a series of randomly selected villages. There were significant differences in the severity of infection with these parasites between the two linguistic groups inhabiting the eastern and western halves of the island. Blood examinations for malaria and microfilariae also differed. It is thought that these differences reflect obscure microenvironmental factors in what would appear to be an epidemiologically homogeneous population.


A case of Rictularia infection of man in New York.

A gravid female nematode was found in histopathologic sections of an appendix in a postmortem examination. This parasite was identified as Rictularia, a genus of small intestinal parasites in numerous mammals. The parasites of this genus have not previously been identified in man.


The association of Schistosomiasis mansoni and proteinuria in an endemic area. A preliminary report.

The association of Schistosoma mansoni infection and proteinuria was investigated by measuring quantitative urinary protein in a defined population in an endemic area in northeastern Brazil. Persons with schistosomiasis had higher mean urinary protein than those without. Two of 162 persons with schistosomiasis had clear evidence of renal disease (pathologic proteinuria, abnormal urinary sediment). These results seemed to be related neither to the intensity of S. mansoni infection as measured by fecal egg excretion nor to the presence of hepatic and splenic enlargement in schistosomiasis.


Effects of portacaval shunting on Schistosoma japonicum infection in chimpanzees: dissociation of pipe-stem fibrosis and glomerulopathy.

Eight of 10 young chimpanzees were infected with the Japanese strain of Schistosoma japonicum. In 6 of these, and in 1 normal chimpanzee, a surgical end-to-side portacaval shunt was constructed during the 8th week of infection. One additional infected chimpanzee was treated successfully with the nitrovinylfuran, SQ 18,506. In the four animals surviving both infection and shunting hepatic portal fibrosis was either absent or mild. In the 7-month survivors and in the drug-treated control animals there was evidence of healed portal endophlebitis and arterialization, but no active schistosomal liver lesion was found. Nevertheless, three of these animals showed variable degrees of active schistosomal glomerulopathy, similar to that seen in the unshunted infected control and to that described in earlier studies. There was a shift of the egg burden from the liver to the lungs, as well as evidence that the number of surviving adult worms had decreased following portacaval shunting. These observations sugggest that schistosomal nephropathy in chimpanzees is more closely related to infection intensity per se than to the degree of liver damage caused by infection.


Polymorphic acetylation of the antibacterials, sulfamethazine and dapsone, in South Indian subjects.

A group of South Indian subjects was studied for their capacities to acetylate sulfamethazine (SMZ) and dapsone (DDS) and to clear DDS from the circulation. An apparent trimodal distribution of acetylator phenotypes was found in 49 subjects (51% slow, 12% intermediate, and 37% rapid acetylators) from measurements of the percentage acetylation of SMZ in 6-hour plasma samples after administration of 10 mg SMZ/kg. The intermediate phenotype was not discernible from either the percentage acetylation of SMZ in urine (collected concurrently with the plasma after SMZ) or that of DDS in plasma after the ingestion of 50 mg DDS by the same subjects. The latter two measurements yielded a bimodal distribution of 59% slow and 41% rapid acetylators, nearly identical to earlier reported distributions of isoniazid inactivator phenotypes in larger numbers of South Indian tuberculosis patients. In the current group, acetylation of DDS and SMZ was positively correlated. The half-time of disappearance (T 1/2) of DDS, an expression of the rate of clearance from the plasma, ranged from 13 to 40 hours. No correlation was found between the subject's capacity to acetylate DDS and the T 1/2 value for DDS. These results were generally consistent with earlier observations made during similar studies of American and Filipino subjects.


Experimental infection of anole lizards (Anolis carolinensis) with Mycobacterium ulcerans by the subcutaneous route.

To test whether herpetofauna could be a laboratory model for Mycobacterium ulcerans, 21 anole lizards were inoculated subcutaneously with viable M. ulcerans, 21 with autoclaved organisms, and 14 with an aqueous solution of 0.01% Tween 80. M. ulcerans was recovered in culture from the slowly progressive lesions which developed at the inoculation site in lizards receiving the viable bacteria. Progressive lesions did not occur in the two control groups. Three patterns of inflammatory response to viable M. ulcerans were observed: 14 lizards developed a diffuse, granulomatous reaction in which acid fast bacilli (AFB) were predominantly intracellular; 1 developed focal, encapsulated granulomas; 5 developed a diffuse, necrotizing granulomatous response in which most AFB were extracellular--similar to the characteristic lesion found in human infections.


Smallpox vaccination revisited. Some observations on the biology of vaccinia.

Sixty-two volunteers were studied to determine their local cutaneous, serologic, and virologic reactions to smallpox revaccination. Of 55 subjects available for examination, 45 (82%) had major cutaneous reactions. Subjects over 30 years old were more likely to have a major reaction. An increase in complement-fixing antibody titer was found in 74% of revaccinees with a major reaction. An increase in complement-fixing antibody titer was found in 74% of revaccinees with a major cutaneous reaction and is felt to be the best serologic indicator revaccination did not yield vaccinia virus. Cultures of the vaccination site demonstrated the virus to be present for a mean of 7.8 days (range 0--18 days) which coincided with separation correlate with antibody response. However, subjects vaccinated more than 3 years previously and subjects with major skin reactions shed vaccinia virus for longer periods than those vaccinated less than 3 years previously or who had equivocal reactions.


The distribution and prevalence of group A arbovirus neutralizing antibodies among human populations in Southeast Asia and the Pacific islands.

Plaque reduction neutralization tests, using five group A arboviruses (chikungunya, Ross River, Getah, Bebaru and Sindbis), were done on sera from human populations in 44 Southeast Asia and Pacific island localities. Specificity of the plaque neutralization test was determined by examining convalescent sera from patients with known alphavirus infections. Chikungunya-specific neutralizing antibodies were demonstrated in sera of persons living in South Vietnam, Northern Malaysia, Indonesia (Kalimantan and Sulawesi), as well as Luzon, Marinduque, Cebu and Mindanao islands in the Philippines. Evidence of Ross River virus infection was found among populations living in West New Guinea and Papua New Guinea mainland, the Bismark Archipelago, Rossel Island and the Solomon Islands. There appeared to be no geographic overlap in the distribution of chikungunya and Ross River viruses, with the separation in their distribution corresponding with Weber's line in the Pacific. Sindbis neutralizing antibodies were found in 7 of 21 populations sampled, but in general the prevalence of infection was low. Four sera, from Vietnam, Malaysia and Mindanao gave monospecific reactions with Getah virus. No evidence of specific Bebaru virus infection was detected. The epidemiology of these five alphaviruses in Southeast Asia and the Pacific islands is discussed.


Acute renal failure following snakebite.

Eight patients with acute renal failure following snakebite were studied. Intravascular hemolysis and disseminated intravascular coagulation contributed to the development of acute renal failure in 6 patients. Direct nephrotoxicity causing acute renal failure is postulated in 2 patients, 1 of whom also revealed evidence of mild, disseminated intravascular coagulation. Three patients had histopathological lesions of acute symmetrical cortical necrosis and 3 had acute tubular necrosis. In 1 patient with acute tubular necrosis, in whom direct nephrotoxicity seemed to be responsible for renal failure, the striking histological feature was a uniform debasement and disappearance of tubular epithelium. In 2 patients with a clinical course of acute tubular necrosis, histological lesions could not be documented. All the 5 patients with acute tubular necrosis regained full recovery of renal function, 3 of them with the help of dialysis and 2 with conservative management. None of the 3 patients with acute cortical necrosis survived in spite of intermittent dialysis therapy.


Changes in cross-resistance spectrum resulting from methyl parathion selection of Culex tarsalis Coq.

Larvae of a field strain of Culex tarsalis Coq. manifesting a broad spectrum of resistance to organophosphorus (OP) insecticides were selected further by methyl parathion pressure in the laboratory. There was a 6.9 times further increase in resistance to methyl parathion in larvae, i.e., from 13.4 times level of resistance in the parental strain to 93.5 times level in the F11 generation. With the exception of fenthion and malathion, cross resistance in larvae the parental strain. The F11 larval population exhibited high levels of cross-resistance to chlorpyrifos (29.6 times), fenitrothion (49.4 times), parathion (55.6 times), fenthion (76.8 times), and chlorpyrifos-methyl (253.8 times). The high levels and broad spectrum of resistance to diverse OP compounds suggest the involvement of more than one mechanism in resistance. Larval selection also affected the spectrum of OP resistance in adults. The F11 adult population exhibited high levels of resistance to dichlorvos (48 times) and chlorpyrifos-methyl (40.1 times) insecticides propoxur, Mobam, Landrin or carbaryl, or to the chrysanthemate insecticide cismethrin. Resistance to the OP insecticides methyl parathion, parathion, fentirothion, fenthion and chlorpyrifos-methyl was found to be fairly stable over nine generations in the absence of methyl parathion selection pressure.


The isolation of Leishmania braziliensis from sloths in Costa Rica.

Eight out of 47 Bradypus griseus and 14 out of 18 Choloepus hoffmanni yielded positive cultures for flagellates from blood, skin, liver or spleen. In some cases, more than one species of flagellate was isolated from one animal or site. Although amastigotes were obtained in tissue cultures from several isolates containing different types of promastigotes, only four of these strains (two from each species of host) were infective for hamsters and considered as Leishmania braziliensis. Infection with one of the strains was possible only after it has been passed through tissue culture.


Biopsy of Onchocerca nodules in the Igbos of Nigeria.

The occurrence of Onchocerca nodules in the Igbos of Nigeria was studied in a biopsy series. There were 90 cases in approximately 5,000 biopsies received in 4.5 years at a central laboratory. The prevalence of infection in males was 1.5 times that of females. The two youngest patients were both aged 3 years; the oldest was approximately 70 years. Of the 79 single-site biopsies, 14 (17.7%) nodules occurred on the head and 65 (82.3%) were done elsewhere. The nodules above the waist line totalled 42 (53.2%) and those below it 37 (46.8%). The favorite location was the forehead cephalically and the hip caudally. Eyelid and breast nodules were also noteworthy.


Angiostrongylus cantonensis in the cerebrospinal fluid of an adult male patient with eosinophilic meningitis in Thailand.

A living, fifth-stage female Angiostrongylus cantonensis 5 mm in length was discovered in the cerebrospinal fluid of a 21-year-old Thai male with eosinophilic meningitis, the second such case to be recorded from Thailand.


Detection of Venezuelan equine encephalitis virus in rural communities of Southern Florida by exposure of sentinel hamsters.

Venezuelan equine encephalitis (VEE) virus strains were recovered from sentinel hamsters exposed in close proximity to homes in rural South Florida. Sentinel hamster surveillance methods over extended periods offer one effective way of uncovering VEE virus activity in relation to human habitation.


New way to stabilize nasogastric tubes.

A new way to stabilize nasogastric tubes is presented, aimed at preventing decubitus ulcerations of the mucosa of the nose and pharynx.


Noncrushing intestinal clamp without handles.

This noncrushing intestinal clamp is so designed that it can be used in poorly exposed areas. It also is so constructed that a scissors-like effect is avoided and satisfactory noncrushing occlusion is obtained.


Further experience with the Childs-Phillips plication operation.

The Childs-Phillips plication operation was performed in forty-two patients, as treatment for recurrent small bowel obstruction in nineteen and as prophylaxis against future intestinal obstruction in twenty-three. Intestinal obstruction occurred later in only one patient. Eight of ten patients with acute peritonitis died in the postoperative period. Consequently, the operation is not recommended in the presence of generalized acute peritonitis.


Hypercoagulability in patients with peripheral vascular disease.

Twenty-seven patients with peripheral vascular disease had studies of thrombin generation, antithrombin III -alues, factor VIII values, platelet adhesitivity, and activated partial thromboplastin time. Of the studies performed, the thrombin generation index, antithrombin III values, and, to a lesser extent, activated partial thromboplastin time were reliable in confirming clinically suspected hypercoagulability. When patients were placed into groups with and without operative complications, it was noted that the group with operative complications had higher average values of thrombin generation index and lower average values of antithrombin III and activated partial thromboplastin time than did the group without operative complications. It is thought that these tests may be useful in selecting those patients with a high risk of thrombotic complications from vascular surgery and who may benefit from anticoagulant management while undergoing necessary vascular reconstructive procedures.


Fistulas of the gastrointestinal tract. Experience with eighty-one cases.

Eighty-one cases of gastrointestinal fistulas are reported. Sixty-seven of these fistulas occurred postoperatively, all of them external, and fourteen occurred spontaneously, all but one internal. Fifty-two patients were treated conservatively and twenty-nine underwent operation, with an overall mortality rate of 23.4 per cent. It is noted that the presence of severe intraperitoneal infection and a high location of the fistula were associated with an unfavorable prognosis, with mortality rates of 31.4 per cent and 48 per cent, respectively.


Cholecystectomy with and without surgical drainage.

Thirty-seven patients who met specific criteria had cholecystectomy without drainage, and thirty-seven matched control patients had cholecystectomy with drainage. This study suggests that surgical drainage after every uncomplicated cholecystectomy is unnecessary and may be unwise. Such drainage may result in an increased incidence of postoperative morbidity and prolonged hospital stay.


Methionine-induced hepatic coma in dogs.

Oral methionine is noncomatogenic in normal dogs, but it is consistently comatogenic in dogs with portacaval shunts in the  presence of elevated ammonia levels. Such action appears to be enhanced by the ammonia itself, since relatively small doses of oral methionine can induce coma when baseline levels of ammonia are above 1,000 mug/100 ml; much higher doses are nesessary for near normal ammonemia. The methionine-induced coma closely reproduces the clinical and electroencephalographic picture of coma in other canine models. Oral methionine does not significantly increase the ammonia levels, but its action is probably mediated by the release of methanethiol (and other less active compounds) from the bowel. Methanethiol levels tend to increase in proportion to the amount of methionine administered, and its comatogenic action may be amplified, up to one hundredfold, by high ammonia levels. Methanethiol levels in comatose patients and the concept of the synergistic effect with ammonia may lead to a clearer understanding of certain enterogenous and dietetic forms of hepatic encephalopathy in cirrhotic patients. The lowering of ammonia levels by hemodialysis or methanethiol levels by activated charcoal hemoperfusion, as attempts to reverse such forms of coma, warrants further investigation.


The continuing challenge of gallbladder cancer. Survey of thirty years' experience at the University of Chicago.

The current concepts of the etiologic factors and spread of carcinoma of the gallbladder are discussed. The experience at the university of Chicago with this condition over a period of thirty years is reviewed. Of eighty-two cases diagnosed during this time, 88 per cent of the patients died within one year of diagnosis and the five year survival rate was 5 per cent. The difficulties in diagnosis of cholecystic neoplasms are considered, and the possibility of increasing diagnostic accuracy by the use of celiac axis angiography, immunologic tests for tumor-associated antigens, peptide hormone assays, and cytologic study of duodenal juice is discussed. The place of palliative surgery in the management of cancer of the gallbladder is outlined. Means of improving the current high mortality of this condition are evaluated, and a plea is made for a controlled trial of the various forms of treatment that have been suggested.


Geometry, blood flow, and reconstruction of the deep femoral artery.

The deep femoral artery is the main source of blood supply to the leg and foot when the superficial femoral artery is occluded. In this situation, the geometry of the trunk of the deep femoral artery represents a stenosis of 50 per cent interposed between the common femoral artery and the collateral circuit of the deep femoral artery. Intimal thickening of only 0.5 and 1.0 mm increases this anatomic stenosis to 64 and 76 per cent, respectively. Beyond the trunk, the cross-sectional area of the deep femoral artery circuit increases at each arterial division. Any reconstruction of the deep femoral artery intended to increase its inflow must extend down to at least its first important bifurcation if it is to overcome this trunk "stenosis". This requirement ex plains the effectiveness of proper reconstruction of the deep femoral artery in avoiding or delaying amputation in patients with ischemic symptoms and occlusion of the superficial femoral artery who are not candidates for femoropopliteal reconstruction. In this group, the absence of plaque on the arteriogram does not contraindicate reconstruction.


Influence of choledochoscopy on the choice of surgical procedure.

1. Direct endoscopy of the biliary tract has been used alone or in conjunction with operative cholangiography as a method of policing choledochal explorations. 2. A series of cases is presented in which endoscopy of the bile ducts has been of significant aid in clarifying the pathologic factors at operation. 3. This experience indicates that operative visualization of the bile ducts deserves a place in the surgical armamentarium.


Idiopathic sclerosing cholangitis. Pathophysiologic observations.

Selective hepatic arteriography and umbilical portography in a patient with idiopathic sclerosing cholangitis revealed uneven distribution of blood flow through the liver, the majority of the contrast media being demonstrated in the central portions of the liver. Mild portal hypertension was present. The stenotic biliary tree offered no unusual resistance to the passage of dye from the main biliary radicals into the duodenum. T tube drainage dramatically relieved pruritus, but clinical improvement with weight gain, disappearance of jaundice and reduction of portal pressure did not occur until after the administration of steroids. After one year of steroid therapy, liver biopsy showed a reduction in the periportal inflammatory reaction and lessening of the diffuse stenosis of the biliary tree. The relationship of these findings to current pathophysiologic hypotheses concerning sclerosing cholangitis is discussed.


Death from hepatic failure after jejunoileal anastomosis.

Severe liver dysfunction and even death from hepatic failure after jejunocolic anastomosis has led to the virtual abandonment of that procedure for the surgical treatment of massive obesity. This complication after the currently employed jejunoileal anastomosis has rarely been described before. We present two cases of hepatic necrosis and death after end to side jejunoileal anastomosis and compare the clinical data and liver function test results in these two patients with findings in 124 other patients who underwent a similar procedure for treatment of morbid obesity. No significant differences could be found that would allow early identification of those patients in whom massive hepatic necrosis was developing. Careful follow-up study and perhaps repeated liver biopsy may be necessary to monitor the hepatic status after jejunoileal anastomosis so that reanastomosis can be undertaken at a time when the damage may be reversible.


Intestinal obstruction.

One hundred severty-one cases of mechanical intestinal obstruction were studied. One hundred fifteen had small bowel obstruction and fifty-six had large bowel obstruction. Adhesion (32.8 per cent), hernia (21.6 per cent), and neoplasm (18.1 per cent) were the cause of obstruction in more than 70 per cent of all cases. More than 40 per cent of patients were older than 60 years and the average age was 52.7. The numbers of males and females were approximately equal. There were twice as many whites as blacks, and the mortality rate was higher among blacks. The overall uncorrected mortality rate was 18.7 per cent. Operation was performed in 105 patients (61.4 per cent), with a postoperative mortality of 19 per cent and corrected postoperative mortality of 4.5 per cent. Contributing factors that were significant were high incidence of metastatic diseases, elderly patients, and delay in admission.


Cystic adventitial disease of the common femoral artery.

Cystic adventitial disease consists of a collection of clear gelatinous material within an aberrant synovial-type cyst located in the subadventitial plane of the wall of a major artery. Recurrent minor trauma is presumed to potentiate mucin production and enlargement of the cyst with resultant arterial occlusion and symptoms of ischemia. It occurs most commonly in the popliteal artery in young men; forty-seven such patients have been reported on. Extrapopliteal disease is distinctly less frequent, occurring three times in the external iliac, three times in the radial, once in the ulnar, and once in the common femoral artery. Surgical therapy of choice is evacuation of the gelatinous material and abrasion of the lining of the cyst. Grafting is occasionally necessary. Long-term results are excellent and recurrence is uncommon.


Measurement of collateral cerebral hemispheric blood pressure by ocular pneumoplethysmography.

A new technic of ocular pneumoplethysmorgraphy for the simultaneous determination of blood pressures in the ophthalmic artery branches of the internal carotid arteries is described. It provides a noninvasive, atraumatic method for assessing hemispheric blood flow. When performed with simultaneous carotid compression, it provides a means for assessing the availability of collateral blood flow to the ipsilateral cerebral hemisphere. Clinical applications related to carotid artery disease and carotid artery surgery are discussed.


Surgical significance of the endothoracic fascia. The anatomic basis for empyemectomy and other extrapleural technics.

Attention if directed to explanation of the endothoracic fascia in several operations described by pioneer thoracic surgeons. The extrapleural plane was extensively and successfully employed in a number of these operations. Re-emphasis of its use seems advisable even today when open thoracotomy is the rule rather than the exception. In selected cases the extrapleural plane can and should be dissected in the aggressive management of relatively localized empyema, with complete enucleation of the infected sac (empyemectomy). This operation can reduce morbidity and prevent prolonged external drainage. The surgical advantage of the extrapleural plane is also apparent in complete parietal pleurectomy for effective palliation of repeated fluid formation. Other instances of intrathoracic disease are mentioned for which dissection in the extrapleural plane can be a safe and time-saving method of treatment. The anatomic considerations relating to the rapid, safe, and effective dissection of the major hilar vessels are also emphasized.


Advances in management of splenic injuries.

Because there is no such thing as "minor splenic injury", the diagnosis of splenic rupture is a major problem after abdominal trauma. Since it is our policy to explore all penetrating abdominal injuries, the problem of early recognition arises in patients with blunt trauma. When abdominal evaluation is difficult because of associated injuries, we increasingly use peritoneal dialysis. This has been particularly helpful in patients with head injury or drug intoxication and has also contributed to earlier operation in patients with signs of hypovolemia but minimal abdominal findings. Angiography has been useful in doubtful cases. Review of our experience in the last five years with splenectomy (298 cases) has revealed complications, particularly thromboembolic, that have changed our management of these patients. The incidence of clinical pulmonary embolism was 4 per cent in patients having splenectomy for trauma as contrasted with 0.5 per cent in patients having laparotomy for trauma without splenectomy. Postoperative platelet evaluations in patients after splenectomy for trauma revealed thrombocytosis. Detailed follow-up platelet studies showed a peak thrombocytosis at about two weeks, averaging 976,000/mm3. In contrast, similar studies in other patients having laparotomy for trauma showed counts of about 200,000/mm3. Because of the high incidence of thromboembolic complications, a low-dose heparin regimen was initiated. There was a 30 per cent incidence of infection postoperatively.


Differential diagnosis of hypercalcemia by the chloride/phosphate ratio.

The serum chloride and phosphate levels were measured and the chloride/phosphate ratios calculated in a group of eighty-four hypercalcemic patients. Although patients with hyperparathyroidism frequently had phosphate levels in the low normal range (less than 3 mg/100 ml) and chloride levels in the nigh normal range (greater than 102 mEq/L), they were nevertheless significantly different from the groups of patients with nonparathyroid hypercalcemia in whom phosphate levels were usually higher (greater than 3 mg/100 ml) and chloride levels usually lower (less than 102 mEq/L). The chloride/phosphate ratio was higher than 33 in 94 per cent of hyperparathyroid patients and lower than 33 in 96 per cent of other hypercalcemic patients. Thus, the measurements of serum phosphate and chloride levels and the calculation of the chloride/phosphate ratios were useful diagnostic screening tests that discriminated between patients with hypercalcemia of parathyroid and nonparathyroid origin with an accuracy of 95 per cent.


Analysis of mortality and morbidity in 100 composite resections for oral carcinoma.

The postoperative morbidity and mortality in one hundred patients who underwent composite resection for oral malignant disease are reviewed. Although there was a 7 per cent mortality and significant morbidity, the majority of patients did well. This procedure offers potential cure for life-threatening malignant disease.


Problems with bovine heterografts for hemodialysis. Recognition, correction, and prevention.

1. Careful examination of the peripheral blood vessels is essential in choosing the site for an arteriovenous heterograft. 2. Ischemia of the hand or fingers was avoided by placing upper extremity grafts in the forearm. 3. In the lower extremity, if peripheral pulses are normal, a straight thigh graft is preferred. 4. The recipient vien in the antecubital fossa should be no less than 4 mm in diameter; in the lower extremity the venous anastomosis should be made to the common femoral vein. 5. "Graft hypertension" is a sign of inadequate venous runoff and should be corrected before false aneurysms develop or occlusion of the graft occurs. 6. Most thrombosed grafts can be reopened and should be explored promptly through an incision near the venous end.


Counterfeit cholecystitis, a common diagnostic dilemma.

Of 238 patients hospitalized with a diagnosis of acute cholecystitis, 20 per cent were ultimately found to have other conditions, namely, renal/ureteral problems most often, followed by diseases of the liver, pancreas, appendix, and thorax. Discriminant factors are discussed. Operations based on misdiagnoses occurred only in the patients undergoing early operation. Painstaking preoperative study and interval cholecystectomy, whenever possible, are recommended.


Treatment of felons.

The pitfalls of traditional concepts in the management of a felon are reviewed. A more rational and uniformly successful method is detailed. This consists of a midvolar, longitudinal incision of the fat pad where the majority of abscesses point. Other incisions are reserved for the few cases in which maximal tenderness is shown elsewhere. An abscess should always be drained where it points. It has not been our intent in this report to discuss the problems of extension of infection beyond the closed space of the distal fat pad or to deal with paronychias and eponychias that simulate a felon by their extension.


Diverticulitis: selective surgical management.

The surgical treatment of complications of diverticulitis remains most challenging. A review of twenty years' experience with one hundred fifteen cases is presented with one proved anastomotic leak and no deaths. Interval primary resection with anastomosis for chronic recurrent disease including colovesical fistula and mesocolic abscess was proved sate with low morbidity. The three-stage procedure for perforated diverticulitis with spreading peritonitis or pericolic abscess was associated with a high rate of complications and morbidity. An aggressive approach with resection without anastomosis in two stages is indicated.


Surgical management of transposition of the great arteries.

Sixty-two patients with transposition of the great arteries, ranging in age from one week to thirty-five years, underwent total corrective surgery during a seven year period at Stanford University Hospital. Reported herein are the first pateint to undergo complete correction at out hospital and every subsequent patient until October 1974. Eleven patients died, an overall hospital mortality of 18 per cent. Two of thirty-two patients with transposition of the great arteries and intact ventricular septum died, one of pulmonary hypertension at seven days of age. Nine of thirty patients with transposition of the great arteries and ventricular septal defect with or without pulmonary stenosis died. Cause of death usually was high pulmonary vascular resistance. The Donovan-Rastelli procedure was performed in ten patients, with three deaths, but all patients survived when the inserted right ventricular outflow contained a xenograft aortic valve. Transposition of the great arteries in the first weeks of life must be considered on the individual merits of each case, but the combined medical and surgical approach must be both expedient and thorough if the patient is to survive.


Use of implantable prostheses for the treatment of urinary incontinence and impotence.

Silicone-Silastic implants to restore continence and potency have been used in one hundred twenty and twenty-five patients, respectively, and in eight patients a combined anti-impotence and anti-incontinence operation has been performed. The results have been gratifying, the complication rate has been minimal with fewer than five patients in our series having infection and a draining perineal sinus after the incontinence implant, and in no patient have delayed problems with the penile implants developed. Because of the design of the penile implants, fracture is extremely unlikely to occur, and the rods can be replaced if necessary because of inadequate length or asymmetry.


Cancer of the bile duct: the occult malignancy.

Primary malignant lesions of the bile duct system are almost always discovered at a late stage, and largely because of this, the prognosis with this disease is poor. Despite this bleak prognosis, many of these lesions are well differentiated and relatively slow growing. In contrast to periampullary lesions, which may be polypoid or papillary with a relatively good prognosis, bile duct cancers are almost always of the infiltrative type and are often scirrhous. Metastases to lymph nodes occur in the majoirty of patients, about half have liver metastases, direct invasion of the liver occurs frequently, extension into the wall of the bile duct often occurs early, periductal involvement often precludes resection, and perineural invasion frequently extends far beyond the limits of resection. The early periductal spread of these lesions along with the anatomic barriers, that is, the portal vasculature, often prevents wide excision of tumors in the supraduodenal portions of the bile ducts. These lesions are difficult to detect accurately and, because of this, often are nonresectable when definitive diagnosis is established. To detect these tumors more frequently during exploration of the extrahepatic biliary system, especially during cholecystectomy, biopsy specimens of any indurated area should be taken. The discovery of white bile in the common duct is highly suggestive of malignant disease, scrapings of indurated areas may establish the diagnosis, and perhaps the interior of the ductal system should be visualized directly with the optical instruments currently available. However, since most intraductal malignant lesions resemble fibrous strictures, direct visualization may not allow distinction between the two; moreover, biopsy may not establish the diagnosis of malignant disease since often the lesions are extensively fibrotic. Retrograde cholangiography with the duodenoscope probably will be used increasingly in the study of various problems in the bile ducts, including malignant disease. It is unlikely, however, that this method will contribute to the discovery of lesions confined to the mucosa, since carcinoma at this stage seldom produces symptoms and duodenoscopy would rarely be carried out in a patient without significant biliary symptoms.


[On the abortive and teratogenous action of volatile and gaseous anaesthetis agents (author's transl)].

The abortive and teratogenic effect of inhalational anaesthetics is well established. This cannot be explained by metabolic activation of the halogenated hydrocarbons but could be due to a noxious effect on the mitotoc spindle. The inhibition of mitosis  is correlated with the lipid solubility and the anaesthetic effect. Numerous experiments give evidence that the effect of anaesthetics can be explained by their reversible binding to nonpolar sites of protein by Van der Waals' bonds affecting protein conformation. The tubular protein of mitotic spindle seems to be highly sensitive to this change of conformation. To prevent abortion and miscarriage in female operating room personnel it is essential not only to remove the halogenated compunds from room atmosphere but also all other anaesthetic gases and vapors such as nitrous oxide and diethyl ether.


[Anaesthetic management of patients with hyperdynamic circulation in hepatic cirrhosis (author's transl)].

Cirrhosis of the liver is frequently associated with arterial hypoxaemia and a hyperdynamic state of the systemic circulation. The hypoxaemia and the circulatory changes probably have a common aetiology, namely, shynting in the systemic and pulmonary vascular beds. Experiences in two well-documented cases suggest that anaesthetic agents may increase arteriovenous shunting and hypoxaemia in patients with hepatic cirrhosis. A plan for preanaesthetic identification and anaesthetic management in this type of patients is outlined.


Pharmacokinetics of ketamine in man.

A method for the analysis of ketamine and of its metabolites is described using gas-liquid chromatography for separation and flame ionization detection. The lower limit of detection for ketamine in serum was 0.025 mug/ml. The pharmacokinetic behaviour of ketamine after intravenous injection may be described in terms of an open two-compartment model. The serum half-life of ketamine was in alpha-phase about 11 min, the predominant half-life for the beta-phase 2.5 h. The half-life of ketamine and its metabolities in urine was comparable to that in serum. It could be shown that the duration of anaesthesia is not only correlated ti ist rapid metabolic breakdown and elimination, but also to the distribution of the drug peripheral tissue.


[Action of central depressants on the nitrous oxide anesthesia (author's transl)].

The synergistic action of seven central depressants three benzodiazepines, two neuroleptics on barbiturate and morphine on the anesthetic activity of nitrous oxide was studied in mice. The benzodiazipines and among them nitrazepam and flunitrazepam were found to be the most potent drugs in this respect; morphine on the other hand was innefective even in toxic doses. There was a significant difference in the slope of log dose-response curves; these curves were much steeper for pentobarbitone, droperidol and chlorpromazine than for nitrazepam, flunitrazepam, and diazepam. The theoretical and practical implications of this difference are discussed.


[Neurophysiological investigation of the central nervous action of the hypnotic agent etomidate in cats (author's transl)].

1. The action of etomidate (0.125-4.0 mg/kg) injected intravenously or into the right atrium (time of injection about 1 sec) was investigated in cats under different central nervous conditions. 2. In decerebrate unanaesthetized animals and in lightly anaesthetized (pentobarbitone) animals with an intact CNS etomidate (0.25-4 mg/kg i.v.) caused a decrease of the spontaneous lumbar fusimotor activity and a strong depression of the fusimotor pinnareflex. Partly a reversal of this reflex from excitation to inhibition was observed. The effects occurred within 20 sec after the injection and lasted for 5-70 min, showing a clear non-linear relationship with the injected dose. 3. In encephale isole preparations etomidate (0.125-1 mg/kg injected intra-right atrially) caused distinct changes of the spontaneous EEB (decrease of frequency, increase of amplitude, occurrence of steeper waves) and a depression of the arousal reactions in the EEB following different stimuli (acoustic stimuli and different stimuli in the area of the face and eyes). These effects occurred within 8 sec after the injection and lasted up to 40 min, dependent upon the injected dose. 4. The character and the principal similarity of the results observed in decerebrate animals and in animals with intact CNS suggest that a considerable part of the action of etomidate consists of a depression of the activity and reactivity of the brain stem reticular formation.


Insertion of central venous catheters through arm veins.

The position of the tip of a central venous catheter inserted through an arm vein is not influenced by the arm or by the vein chosen. There may be some advantage in inserting the catheter with the arm at the patient's side, although there seems to be no benefit from turning the patient's head towards the side of insertion. Because the most common malposition from an apparently uneventful insertion is due to the catheter tip entering the internal jugular vein, neck compression has been established as a useful test. If the catheter tip is well into the internal jugular vein, compression on that side of the neck should cause a rise in the recorded pressure of 10 or more cm H20. This rise should not occur on compression of the other side of the neck. We wish to emphasize that it is important to confirm radiographically the position of the catheter tip.


Heat balance during surgery involving body cavities.

Three groups of adult patients were anaesthetized for elective intra-abdominal surgery. In one group, patients were ventilated with dry anaesthetic gases, and these patients all lost heat. In the second group humidification was used to annul respiratory heat exchange, and these patients lost heat initially but tended to regain heat during anaesthesia. The third group, in addition to humidification, had surface insulation and all these patients gained heat. It is suggested that conservative methods which negate heat loss are able to prevent hypothermia by the retention of metabolically produced heat.


Control of heat balance during arterial surgery.

Patients were studied to quantitate methods used to prevent heat loss during vascular surgery. A combination of techniques limiting heat loss were shown to prevent hypothermia. In addition it was shown that heat balance in patients undergoing vascular surgery did not differ from that in patients undergoing other forms of surgery.


An intensive care unit in a rural area.

Factors that governed the setting up of a multipurpose, temporary Intensive Care Unit of six beds, in a remote area of Malaysia and the experience of operating it for more than two and a half years are outlined.


Selective bronchial blocking in children.

The use of the Fogarty arterial embolectomy catheter as an endobronchial blocker in infants and children has previously been reported. The further development of this technique is outlined and its use in two patients is described.


Severe drug overdose: results of treatment.

The incidence and management of severe drug overdose patients over a five-year period is presented, together with results and complications. Emphasis is placed on the importance of conservative measures with minimal need for more aggressive methods of treatment.


Fiberoptic endoscopy of the respiratory tract in the intensive care ward.

An outline is given of the use of fiberoptic instruments in the management of some respiratory problems in the Intensive Care Ward. In particular, bronchoscopy and inspection of the trachea and larynx prior to closure of tracheostomy are described.


Autonomic manifestations of tetanus.

Two patients with tetanus are reported to illustrate the involvement of the sympathetic and parasympathetic nervous system respectively. Aspects of the autonomic manifestations of tetanus are illustrated and discussed.


Althesin in shared airway anaesthesia.

The anaesthetic management for surgical procedures involving the larynx and/or trachea and the problem of the shared airway are outlined. The use of intravenous Althesin on 31 patients (43 administrations) is described. It is suggested that Althesin has a place in the management of these patients.


A technique of nasotracheal intubation in patients with recent facio-maxillary injury.

A technique of nasotracheal intubation in patients with recent facial injury is described. Oral intubation is performed initially to ensure the safety of the patient during the procedure of nasal intubation.


Hypermagnesaemia caused by parenteral nutrition in patients with renal failure.

Iatrogenic hypermagnesaemia may occur when magnesium is infused in the presence of compromized renal function. Three cases are described and the renal control of magnesium is discussed. If magnesium is considered necessary in the presence of decreased renal function, reduction in dosage and frequent monitoring of serum magnesium levels should be undertaken.


An infusion set for parenteral nutrition.

An attachment for a standard intravenous infusion set is described. It allows delivery of carbohydrate and amino-acid solutions in a manner that favours maximum utilization and reduces the risks of metabolic complications. It also permits, with ease, repeated alterations of infusion regimes when this is considered necessary.


Latent and overt shock.

Reference is made to the impact of unfamiliar political philosopies and new social attitudes on an unprepared medical profession, and it is suggested that the latter should prepare for even more profound changes in the future.


Assessment of arterial blood oxygenation in various states of acute respiratory failure.

The study contains an analysis of the clinical course of 48 patients with acute respiratory failure. The degree of arterial hypoxaemia and respiratory failure were correlated with the value of true pulmonary shunt of non-oxygenated blood. Measurements of the shunt were carried out serially during treatment and it was calculated from the shunt equation of Berggren. It was found that the pulmonary shunt is a good index of arterial blood oxygenation in cases of acute respiratory failure. The value of 47% of shunt was accepted as that with is incompatible with survival. It was demonstrated that determinations of pulmonary shunt are superior to A-aP02 measurements in assessment of the ventilatory function of the lungs.


Morphological changes of tracheobranchial mucosa in dogs caused by breathing through a surgically produced tracheal fistula.

The author studied the morphological changes developing in the tracheobronchial mucosa following a surgical tracheal fistula. The experiments were carried out on 19 dogs which were divided into 2 groups. Group I included 10 dogs, in which specimens were obtained by bronchoscopy; in group II, 9 dogs, specimens were obtained directly. Histological examinations were carried out by Gomori's reaction and hematoxylin-eosin staining method. Histo-chemical tests included PAS reaction and alcian blue stain. The results showed that after 24 hours morphological changes mainly involved the tracheal mucosa and their characteristic feature was the variety of forms of lesions of the epithelium covering the mucosa. The longer the duration of the fistula the more these changes increased in intensity and involved further parts of the tracheobronchial tree. The author also took into account the living conditions in the kennels where the dogs were kept following the tracheostomy. The changes observed were compared with those reported by other authors and the correlation between the occurrence of these changes and the environmental conditions and length of breathing through the surgically produced fistula was analysed.


Changes in the dynamic compliance coefficient of the lungs and breathing mechanics during administration of diethyl ether and halothane for general anaesthesia with spontaneous respiration.

Changes of the dynamic compliance coefficient of lungs were studied during diethyl ether and halothane anaesthesia. Determining lung compliance at the same time it was possible to show the effect of these agents on changes in the magnitude of breathing work necessary to overcome elastic and non-elastic resistances. The investigations were carried out on 31 patients during general anaesthesia with spontaneous respiration. The determinations revealed that the tidal volume (TV) was decreased in relation to the initial values (before anaesthesia) indicating a depressing effect of these agents on the processes of respiration. Changes in the tidal volume and intrapulmonary pressure decided on the changes of the pulmonary compliance coefficient and the magnitude of breathing work. The coefficient of pulmonary compliance decreased during diethyl ether administration by 18.8% and during halothane by 30.9%. On the other hand the work necessary to overcome respiratory resistances increased mainly during ether anaesthesia owing to a significant rise in the non-elastic resistance (bronchial secretion).


Evaluation of dynamic compliance of lungs and disturbances of breathing mechanics in patients following laryngectomy for carcinoma of the larynx.

The purpose of study was to observe changes which may develop in the mechanics of breathing following laryngectomy in patients with carcinoma of the larynx as compared with the pre-operative conditions. The studies were carried out on a group of 29 patients, performing the measurements twice, i.e. before operation and after laryngectomy and tracheostomy. The measurements were done using a Godart Compliance-Test type 121 apparatus. The value of the coefficient of dynamic compliance of the lungs was determined together with the magnitude and type of work necessary to overcome respiratory resistance. It was found that after the operation the coefficient of dynamic compliance of the lungs increased by 63.7% while the total work of breathing decreased by 38.7% and the work necessary to overcome the elastic resistance of the lungs fell by 33.7% and that for overcoming the non-elastic resistance fell by 49.3%. The most significant changes in breathing mechanics observed after the operation concerned the ratio or breathing work necessary to overcome the non-elastic resistance to the total breathing work. This ratio was 43.35% pre-operatively and 34.11% post-operatively. The obtained results suggest that impairment of laryngeal patency caused by the tumour raises the breathing work and reduces the coefficient of dynamic compliance of the lungs due mainly to an increased non-elastic breathing resistance.


Observations on the effects of drugs used in general anaesthesia for ear operations on renal functions.

The purpose of this study was: 1) to observe the renal effects of atropine and pethidine administered intravenously in premedication, 2) to assess the renal effects of diethyl ether and halothane, 3) to study the effects of respiration on the renal functions in general anaesthesia and 4) to evaluate the antidiuretic action of Octapressin used for infiltration of the field of operation during anaesthesia. The studies on the renal effects of the drugs used in premedication were carried out on 27 patients. The renal effects of general anaesthesia and operation on renal functions were studied in 20 patients divided into 2 groups. Group I comprised of patients under diethyl ether anaesthesia while in group II halothane was used. In both groups subgroups A and B were isolated depending on the type of respiration applied during general anaesthesia (subgroup A -- manually assisted respiration, subgroup B -- spontaneous respiration). In all patients in groups I and II Octapressin was used for infiltration of the field of operation. Its renal effects were assessed on the results of determinations in 5 cases (subgroup II-A) anaesthetized with halothane and receiving manually assisted respiration. These results were compared with those in group III which comprised of 5 patients anaesthetized with halothane who were not given Octapressin infiltrations. The following conclusions have been drawn from these results: 1) Atropine and pethidine administered intravenously in therapeutic doses significantly reduce glomerular filtration. 2) Changes in renal functions observed during general anaesthesia and operation were the result of ADH secretion stimulation and changes in renal haemodynamics. 3) No differences were observed between the renal effects of diethyl ether and halothane which was due, probably, to compensatory renal mechanisms regulating renal circulation and osmotic equilibrium in the organism. 4) No differences were observed also in the renal effects of various method of ventilation used during anaesthesia. 5) Octapressin used in therapeutic doses for infiltration of the operation field had no potentiating effect on the antidiuretic action of general anaesthetic agents.


Ultrastructure of the developing fetal hepatocyte of Macaca arctoides: a proposed model for studies of fetal drug metabolism.

The ultrastructure of the hepatocyte of the fetal stumptail monkey was examined with the aim of defining a possible model for studies of fetal drug metabolism. Hepatocytes from fetuses of 80 and 160 days gestation, as well as from one animal one week of postnatal age, were examined and compared to human fetal hepatocytes at 12 and 16 weeks gestation. Marked variation was observed in the amount of lipid and the distribution of organelles within the cytoplasm of the hepatocyte in the monkey population. These differences were attributed to genetic variation. Two changes were seen which correlated with developmental age. The amount of hemopoietic tissue decreased and the amount of smooth endoplasmic reticulum increased as the animal matured. The problems of genetic variation and the relative number of hepatocytes at different stages of development were discussed relative to the use of this animal as a model for fetal drug metabolism studies. Attention to both of these problems is considered necessary for the interpretation of biochemical data in future studies.


Hematopoiesis in the embryonic mouse spleen. II. Alterations after phenylhydrazine administration to the mothers.

The effect of phenylhydrazine (PHZ) on the hematopoietic events in the embryonic spleen of C57Bl/6J mice was examined by light and electron microscopy. Following PHZ in injections to the mothers, the embryonic spleen revealed a marked increase in erythroid precursors, with a shift to mature cells. This phenomenon was part of a more generalized stimulation of erythorpoiesis, expressed by a shift to mature red cell precursors in the embryonic livers and an increase in the percentage of non-nucleated cells in the embryonic peripheral blood. Concomitantly stimulation of phagocytosis in the spleen of embryos in the early gestational days and increased vascularity were observed, and a later effect of granulocytopoietic stimulation. The effect on erythropoiesis in the embryonic spleen might be a sequence of erythropoietin stimulation, either in the mothers or the fetuses, due to anemia and hypoxia following PHZ injections.


The development of the granular convoluted duct in the rat submandibular gland.

The development of the granular convoluted duct in the submandibular gland of male rats, 4 to 12 weeks of age, was investigated. During this period, the average weight of the gland increased from 213 to 526 mg, the total DNA and RNA contents doubled, and the protein content tripled. Radioautographs were prepared from Epon embedded sections of the gland of the rats given 3-H-thymidine and stained with toluidine blue. The glands of 4-week-old rats consisted mainly of acinar cells (45%), intercalated ductal cells (20%) and striated ductal cells (16%). A few granular convoluted ductal cells were seen in the striated duct close to the intercalated duct. The frequency (and absolute number) of granular convoluted ductal cells increased linearly from 1% (3 X 10-6) at four weeks to 26% (68 X 10-6) at eight weeks, while the calculated number of striated ductal cells remained stationary. The absolute number of acinar cells and intercalated ductal cells nearly doubled between four to eight weeks of age. The proliferative activity of all cell types declined with age but between six and ten weeks of age the rate of proliferation of ductal cells was relatively higher than the rate of proliferation of the acinar cells. Morphologically the size and number of granules in the granular convoluted ductal cells increased with age. Based on the above data it is concluded that the granular convoluted ductal cells developed from that segment of the striated ductal cells which is in close proximity with the intercalated ductal cells. The heterogeneity of the granules in the granular convoluted ductal cells observed from six weeks of age might denote the functional diversity of the cells.


A smooth muscle plexus associated with the aqueous outflow pathway of the rabbit eye.

Smooth muscle cells were demonstrated adjacent to the aqueous outflow pathway in rabbit eyes. The cells were arranged as a discontinuous band, one to three layers thick and extended from the termination of Descemet's membrane to the ciliary body. Most of the cells were oriented with their long axes at right angles to the aqueous plexus, but many were arranged in a direction parallel to the plexus. The organization of the cells suggests that their contraction would exert a bi-directional force, and therefore, affect aqueous outflow resistance.


Mitochondrial pleiomorphism in sustentacular cells of Xenopus laevis.

The mitochondrial population of sustentacular cells in the testis of the amphibian, Xenopus laevis, has been examined by electron microscopy. Three distinct types of mitochondria have been observed. The first and most common mitochondrial type is a "typical" organelle with a rod-like profile containing tubular to plate-like cristae. The second mitochondrial form is characterized externally by irregular bulbous protrusions and internally by increased numbers of tubular cristae. The third mitochondrial type, which is usually ovoid in profile, has the most unusual internal membrane configuration, consisting of pleated folds pierced by regular rows of fenestrations. Mitochondrial type one is found in all sustentacular stages, mitochondrial type two first appears in sustentacular cells surrounding early spermatids, and mitochondrial type three is observed only in sustentacular cells surrounding spermatozoa. These observations indicate that discrete subclasses of mitochondria are present in sustentacular cells of Xenopus.


Electron microscopy of the intestine of the African lungfish, Protopterus aethiopicus.

Electron microscopic observations are reported on the intestine of the African lungfish, Protopterus aethiopicus. The lungfish has a spiral valve rather than a true stomach. Segments of mucosa from this area reveal, by transmission microscopy, that most cells have distinct striated borders with parallel microvilli. Fibrils within the core of the microvilli extend deeply into the cytoplasm. Microvilli on the surface of goblet cells are less regularly arranged than those of absorptive cells. Interspersed among the cells with striated borders are cells, similar in cytologic appearance except that they are covered with tufts of kinetocilia. By transmission electron microscopy, abnormal cilia having one complete complement of microtubules plus incomplete sets from other cilia which share some of the peripheral doublets of the complete cilium are enclosed by a single membrane. Cilia are usual in the intestine of many lower forms but ordinarily absent in higher vertebrates. Their functional significance in this primitive fish is unknown.


Vein size in intact and hysterectomized mice during the estrous cycle and pregnancy.

The diameters of the ovarian, uterine, and femoral veins and the inferior vena cava were measured during stages of the estrous cycle in intact and hysterectomized mice and at intervals during pregnancy in mice with embryos in both uterine horns or in only the left horn. At metestrus I vein sizes were the least and were not significantly different in intact and hysterectomized mice. Ovarian and uterine veins showed the same or increased diameters at other stages of the cycle; veins enlarged progressively during pregnancy in intact mice. Non-gravid uterine horns showed little size increase as compared to gravid horns. Increases in vein diameter appeared to be correlated with local production of reproductive hormones. Evidence for transuterine migration of embryos was observed in 21 of 53 mice in which one uterine tube had been ligated or one ovary had been removed.


The fine structure of the myoneural junctions in the body wall muscles in Branchiobdella pentodonta Whit. (Annelida, Oligochaeta).

The ultrastructure of the myoneural junctions in the body wall muscles has been studied in Branchiobdella pentodonta Whit. A single junctional type has been found. Within the terminal axon there are two types of vesicles, which differ in number, size and electron opacity. The junctional gap contains the basement membrane. The post-junctional membrane displays concave patches on which slender projections arising from the outer lamina of the sarcolemma extend into the junctional gap. These concave patches overlie a cytoplasmic lamina made up of electron dense material.


The implantation chamber, blastocyst and blastocyst imprint of the rat; a scanning electron microscope study.

Splitting the uterus longitudinally through implanatation sites makes it possible to obtain access to blastocysts and implantation chambers during stages of implanatation of the blastocyst in the rat. On the afternoon of day 5 of pregnancy, blastocysts lie in a shallow antimesometrial depression and tend to fall free of the uterus when the chamber is opened. On day 6, blastocysts are oriented in a mesonmetrial-antimesometrial plane, occupy a distinct implantatopm chamber, and tend to adhere to one side or the other of the uterus, leaving an imprint on the contralateral side. After about noon of day 6, some of the blastocysts split in half laterally, and by day 7 all blastocysts which are exposed are split. In addition to demonstrating increased adhesion of blastocyst to uterine epithelium, the procedure clearly shows the progressive elongation of the imlantation chamber. The embrvonic cell mass is specifically oriented on day 6, and is clasped but not distorted, whereas the abembryonic trophoblast is slightly compressed and indented by the uterine epithelium. The microvilli of the uterine epithelium within the imprint become progressively flattened when compared to the microvilli of the implantation chamber outside of the imprint. The method provides a means of gaining direct access to the surface of uterine epithelium precisely where it has been in association with the blastocyst not only for scanning electron microscopy but also for studies of the properties of the surface constituents.


The development of proline-containing extracellular connective tissue fibrils by chick notochordal epithelium in vitro.

Notochords were isolated from Hamburger-Hamilton stages 13-15 chick embryos by trypsinization and microdissection. These were shown by electron microscopy to be completely devoid of extracellular materials or mesenchymal contaminants. Cultivation of notochordal isolates was carried out on a non-collagenous (Falcon Plastic) substratum for 0 to 48 hours. At 12 hours of in vitro incubation, a discontinuous basal lamina could be demonstrated on the surface of notochordal cells. This was followed by the appearance of microfibrils of various sizes and other components of the extracellular matrix. By 48 hours of in vitro incubation, the same extracellular materials which surround the notochord in vivo (notochord sheath) could be demonstrated in vitro. Autoradiographic studies show that tritiated proline is taken up by notochordal cells and secreted to the extracellular space where label is associated with basal lamina, microfibrils and ground substance. When cis-hydroxyproline, a known collagen-specific inhibitor is added to the system, tritiated proline label is located primarily intracellularly and fewer areas of active fibrillogenesis are noted. This suggests that ultrastructurally recognizable materials produced by notochordal cells in vitro may be at least partially collagenous. Significantly, these materials are produced in vivo at the same time (following stage 10) that notochordal tissues actively induce somite differentiation and cartilage formation. It seems reasonable that a biochemically or ultrastructurally identifiable component of the extracellular matrix may possibly mediate such induction.