Serum progesterone and serum human chorionic gonadotropin in gestational and nongestational choriocarcinoma.

Serum progesterone was assayed by the competitive protein-binding technique in 20 cases of gestational choriocarcinoma and one case of nongestational choriocarcinoma. Serum human chorionic gonadotropin (HCG) was simultaneously measured from the same blood samples by the hemagglutination-inhibition technique. Serum progesterone in choriocarcinoma ranged from 1.3 to 182.9 ng. per milliliter with a mean +/- standard error of the mean of 36.2 +/- 10.2 ng. per milliliter. Serum HCG ranged from 0.6 to 1,280 I. U. per milliliter. In 11 patients with choriocarcinoma, serum progesterone levels were indistinguishable from values obtained during the luteal phase of the normal menstrual cycle; six patients had values similar to those found in early normal pregnancy and four patients with postmolar villous choriocarcinoma had elevated serum progesterone. There was a significant correlation between serum HCG and serum progesterone (r = + 0.5652, p = 0.005). The significance of these findings is discussed with reference to the likely source of progesterone in choriocarcinoma.


Surgical repair of genital prolapse after hemipelvectomy.

A patient is presented who had hemipelvectomy for fibrosarcoma of the left upper femur, subsequently was delivered of two term infants vaginally, and came to us 11 years after hemipelvectomy because of genital prolapse. The technical difficulties involved in repair and the innovations used to overcome these difficulties are discussed. We have been unable to find a report of genital prolapse associated with hemipelvectomy anywhere in the English literature.


Histochemical demonstration of lysosomal hydrolase activity in endometrial mononuclear cells. I. Normal endometrium.

Interstitial cell reactivity for lysosomal hydrolases was demonstrated in 67 endometrial specimens with histochemical techniques. Cyclic changes in the number of reactive cells corresponded to the stage of the menstrual cycle. Techniques for galactosidase and glucuronidase showed increasing numbers of reactive cells through the late secretory stage. Staining for glucosaminidase and nonspecific esterase also increased in late secretory endometrium. In contrast, acid phophatase activity was biphasic, and that of leucine aminopeptidase remained relatively constant. Only minimal interstitial staining was seen in prepubertal and postmenopausal specimens.


Histochemical demonstration of lysosomal hydrolase activity in endometrial mononuclear cells. II. Abnormal endometrium.

The mononuclear cells in the endometrial stoma change in reactivity for lysosomal hydrolases during the menstrual cycle. Lymphoid follicles may occur in the stroma in any phase of the cycle and have been found in gestational endometrium. However, these cells have no significant lysosomal activity. Alterations in the endometrium are reflected in modified patterns of activity. Endometritis, association with an intrauterine contraceptive device, pregnancy, and adenocarcinoma result in increased numbers and staining intensity of mononuclear cells. In contrast, no consistent changes were apparent in foci of glandular hyperplasia, and decreased staining was seen in atrophic areas of endometrium. These data suggest that interstitial mononuclear cells are a sensitive monitor of morphologic changes in the endometrium.


Femoral neuropathy following abdominal hysterectomy.

Femoral neuropathy occurs too often after abdominal hysterectomy. This study investigates possible mechanisms of injury to the femoral nerve and possible means of prevention.


Pregnancy-induced hypertension complicated by acute liver disease and disseminated intravascular coagulation. Five case reports.

Five cases of pregnancy-induced hypertension complicated by acute liver disease and DIC are presented. Initial misdiagnosis is described, with appropriate laboratory and histologic documentation of the true condition. Specific therapeutic recommendations are discussed and pathophysiologic mechanisms are suggested.


Enzymatic differentiation in human amniotic cells.

Enzymatic study in noncultured amniotic fluid cells from 87 women at different stages of pregnancy was performed by electrophoresis. Of these patients, 33 had normal pregnancies and the remaining 54 had various complications of pregnancy. The electrophoretic patterns of lactate dehydrogenase, alpha-esterase, and acid phophatase were altered in samples obtained either at different gestation periods or from normal and complicated pregnancies. Malate dehydrogenase and protein bands did not show any alteration. Glucose-6-phosphate dehydrogenase and alkaline phophatase were not detectable. 6-Phosphogluconate dehydrogenase was detectable in samples of complicated pregnancies. The significance of the altered patterns of enzymes is discussed.


Prolactin in normal pregnancy: relationship of maternal, fetal, and amniotic fluid levels.

Serum prolactin was measured simultaneously by a homologous radioimmunoassay in 92 parturients and their offspring at term, and in maternal serum and amniotic fluid during various stages of normal pregnancy. Serum levels of 208 +/- 8 ng. per millilter were found in maternal blood; the corresponding levels in the cord serum were 354 +/- 14 ng. per milliliter. Prolactin levels in amniotic fluid were found to be 2- to 10-fold higher than the corresponding levels of the mothers. The possible source of the amniotic fluid prolactin molecule, which is identical with the human pituitary molecule, is discussed.


Lumbar epidural analgesia with bupivacaine in labor. Drug concentration in maternal and neonatal blood at birth and during the first day of life.

Lumbar epidural analgesia with bupivacaine was administered to 33 women for relief of pain during labor. At delivery blood samples were drawn from the umbilical cord vessels and from a maternal peripheral vein. Blood samples were also collected from the noenate and its mother, 1, 4, and 20 hours after delivery. Analyses of bupivaccaine concentrations were carried out in all samples with a gas-chromatographic technique. The drug concentration in the umbilical vein (UV) was usually higher than the corresponding umbilical artery value (UA), but with increasing time interval between the last bupivaccaine infection and delivery the UA/UV drug concentration ratio rose. After delivery the rate of drug decline in blood was similar in mother and newborn infant. The clinical condition of the infant was unrelated to the drug concentration in the umbilical cord vessels.


Lack of effect of methyl-ergonovine on postpartum lactation.

There is little information about the action of ergot derivatives other than bromocriptine (CB 154) on plasma prolactin and milk secretion in human beings. In a recent report it has been suggested that ergonovine might interfere with lactation when administered post partum. The present study shows that methyl-ergonovine (Methergine), a closely related compound, has no action on prolactin or milk secretion as measured in a group of 10 breast feeding mothers in comparison with another 10 untreated puerperas.


The effect of maternal demographic factors on infant mortality rates. Summary of the findings of the Louisiana Infant Mortality Study. Part I.

Birth and infant death certificates for Louisiana in 1972 were matched and reviewed to identify groups particularly in need of close medical support and counselling during the identify groups particularly in need of close medical support and counselling during the life phases of preparation for reproduction, gestation, and parenthood. From all recorded birth and infant death certificates for 1972 (69,556 birth and 1,541 death certificates) infant, neonatal, and postneonatal mortality rates were computed for maternal demographic (intrinsic patient physiocal and life-style characteristics) factors including age, race, parity by age cohort, education, and legitimacy. Excessive infant deaths were found among illegitimate offspring, except in mothers less than 15 years of age or nonwhites over 35 years of age; the less educated; those having too many children too soon; those of low birth weight; and whites relying on Charity Hospitals. An increased mortality rate was seen with nonwhites and with the younger and older mothers.


The effect of availability and utilization of prenatal care and hospital services on infant mortality rates. Summary of the findings of the Louisiana Infant Mortality Study. Part II.

A total of 69,556 birth and 1,541 death certificates from Louisiana, 1972, were reviewed. Infant, neonatal, and postneonatal mortality rates were computed for number of prenatal visits, type of hospital of delivery, hospital vs. nonhospital delivery, and geographical access to health care. The mortality rates were twice as great for infants born outside of hospitals. With no prenatal care, the infant mortality rates were between four- and tenfold greater than the rates of women receiving more than nine visits even when race, poverty, geography, and birth weight were considered. Infant mortality rates were twice as high in the neonatal period and three times greater in the postneonatal period among the poor who utilized charity hospitals. This study illustrates a method which could be incorporated into state vital statistics reports which would detect populations at risk of excess infant deaths and would provide a more refined analysis of birth and infant death data to monitor improvements in care of high-risk groups.


Cardiovascular changes associated with fetal breathing.

Studies were carried out on seven fetal lambs, 3 to 1 weeks prior to the expected date of delivery to determine if, during fetal breathing, cardiovascular events were similar to those described as occurring with respiration after birth. The following changes were observed; (1) a slight decrease in pressures with the initiation of the rapid inspiratory movements followed by: (2) a marked elevation of the systolic and diastolic pressures; (3) a cyclic variation characterized by a fall in arterial pressure with inspiration; (4) a variable acceleration of the heart rate; and finally, (5) a typical respiratory arrhythmia. These findings demonstrated that, during fetal respiratory movements, there are some cardiovascular changes which are specific to this period of life. There are other changes which are identical to what has been observed after birth. These latter cardiovascular changes imply that the endotracheal pressure variations are the reflection of authentic inspiratory movements under the influence of the central nervous system.


Ocular manifestations of Gaucher's disease.

A 27-year-old woman not only had the usual clinical and laboratory features of the adult form of Gaucher's disease but also had typical pingueculae and a peculiar lesion with a pigmented temporal edge in the fundus of her left eye. Bone-marrow aspiration demonstrated infiltration by Gaucher's cells and a biopsy of the conjuctival masses disclosed areas of infiltration by Gaucher's cell beneath normal epithelium.


Rhabdomyoma of the orbit.

To our knowledge, this is the first fully documented case of an adult-type orbital rhabdomyoma in an 8-year-old white boy, which originated in the belly of the medial rectus muscle and grew into the anterior orbit to incorporate the trochlea. Incomplete excision resulted in recurrence; the lesion was misinterpreted as a rhabdomyosarcoma and exenteration was performed. The patient was free of disease 25 years later. Reexamination of original pathologic material showed the typical histology of an adult-type rhabdomyoma. Adult-type rhabdomyoma, the most differentiated tumor in a spectrum of benign and malignant striated muscle neoplasms, should be distinguished from fetal rhabdomyoma (also benign) and pleomorphic rhabdomyosarcoma, the malignant striated muscle tumor most likely to be confused with rhabdomyoma. An awareness of the benign nature of rhabdomyoma (rhabdomyoma never evolves into a sarcoma) should prevent unnecessary radical surgery. The tumor can be adequately managed by a local excision that includes all the lobulations of tumor within a margin of normal tissue.


Surgical revision of the upper eyelid fold.

We performed surgery on 107 patients primarily with blepharoptosis and eyelid fold abnormalities, between 1973 and 1974. Production of an eyelid fold at the time of an initial blepharoptosis procedure should be a primary goal. Lack of a distinct symmetrical upper eyelid fold constituted a cosmetic blemish and necessitated revision.


Rhabdomyosarcoma of the orbit in the newborn.

A full-term black boy had a 2- to 3-cm, round, bluish mass on his right lower eye-lid at birth, later diagnosed as rhabdomyosarcoma. It was cystic in nature and extended into the nasal cavity. The tumor was initially classified as neuroblastoma. The child died eitht months later and necropsy report confirmed an original ophthalmologic pathology diagnosis of embryonal rhabdomyosarcoma.


Leiomyoma and leiomyosarcoma of the orbit.

Comparison of the clinical and pathologic features of two orbital leiomyomas, two leiomysarcomas, and one embryonal rhabdomyosarcoma showed the leiomyomas occurred in young individuals and the leiomyosarcomas in older patients. The histopathologic diagnosis rested on the intense cytoplasmic eosinophilia and nostriated longitudinal cytoplasmic filaments demonstrated by means of the trichrome stain. The leiomyosarcomas disseminated 15 months and seven years after their orbital presentations. The treatment of both leiomyoma and leiomyosarcoma is surgical. Leiomyomas are encapsulated growths that may have small satellite nodules projecting from the main tumor mass; thus, a margin of normal tissue should also be excised, lest a small lobulation be left behind to serve as the seed for a late recurrence. Once the diagnosis of leiomyosarcoma has been made, and no evidence of metastasis has been found after a thorough systemic evaluation, the orbit should be exenterated, because the tumor is unencapsulated and liable to widespread dissemination. Rhabdomyosarcoma has a much more fulminant course than leiomyosarcoma, and especially more so than that of leiomyoma of childhood. The histopathologic diagnosis of a malignant smooth muscle tumor in a child should always be questioned, since embryonal rhabdomyosarcoma is a much more likely diagnosis.


Retinal hemorrhages in posterior vitreous detachment.

Detachment of the posterior vitreous can cause clinically significant retinal hemorrhage. Two patients with acute posterior vitreous detachment had massive retinal hemorrhages overlying the optic disks. These absorbed in time without sequealae. A third patient had numerous small blot hemorrhages scattered near the optic disk and macula. A fourth patient presented with a small macular hemorrhage causing temporary visual loss. All patients had moderately severe myopia and were in good health without hypertension or diabetes. There was no history of trauma or Valsalva maneuver. Hematologic and coagulation studies were normal. These cases indicate that retinal hemorrhages due to posterior vitreous detachment may be strikingly large, multiple, and, when involving the macula, cause temporary visual loss.


Gyrate atrophy of the choroid and retina with hyperornithinemia.

A case of gyrate atrophy of the choroid and retina and hyperornithinemia in a 28-year-old man was subjected to extensive clinical and biochemical investigation. The familial occurrence of the ocular disease and of abnormality of amino acids was unique to this patient, being absent in parents and siblings. He presented with progressive visual loss, and had cataracts and large areas of peripheral lacumar atrophy. Clinically there was no other abnormality. However, he was hyperuricemic and had an abnormal electroencephalogram. Despite otherwise normal biochemical indices  of hepatic, renal, and muscle function, selective catheterization of an artery, the hepatic vein, the renal vein, and a deep forearm vein showed all of these circulatory beds to be producing ornithine according to arteriovenous difference measurements. Cerebrospinal fluid and urine contained increased amounts of ornithine. Though electromyography was normal a muscle biopsy specimen was abnormal. Clinical tests including arginine loading, glucose tolerance testing, and other measurements of blood variables provided inferences as to the metabolic locus of the abnormality. The syndrome is a systemic multiorgan disorder in which the choriod and retina would appear to be target organs and the hyperornithinemia to be of as yet undetermined cause and pathogenic significance.


Histologic localization of sodium fluorescein in human ocular tissues.

We studied the distribution pattern of sodium fluorescein in human eyes microscopically. The ciliary body showed early and diffuse leakage, with staining of the basement membrane of the nonpigmented ciliary epithelium, indicating movement of fluorescein from the ciliary body into the aqueous humor. After five minutes the iris stroma stained with fluorescein, probably from the aqueous humor. The retinal vessels and retinal pigment epithelium were impermeable to fluorescein. Corresponding to the background fluorescence seen in fluorescein angiography, fluorescence was present in Bruch's membrane and in the stroma of the inner one third of the choroid. Drusen stained most intensely in areas of greatest PAS positively. Early fluorescence of the optic disk was the result of intravascular perfusion of the dye. Minimal diffusion of fluorescein from the fenestrated choroidal vessels across the border tissue of Elschnig into the peripheral optic nerve bundles was observed. Late fluorescene of the optic disk was due mainly to fluorescein staining of the lamina scleralis and glial columns.


Xerophthalmia and anterior-segment blindness among preschool-age children in El Salvador.

A countrywide prevalence survey of 9,508 children was conducted in El Salvador to determine the prevalence of anterior-segment abnormalities and magnitude of clinical vitamin A deficiency. Thirty-six children had corneal opacities, 56% of them secondary to trauma. Such traumatic corneal opacities were 19 times more frequent among urban than rural children, 57.6 vs. 3.1 per 1,000. Keratomalacia accounted for only 8% of all corneal opacities, and for one (and possibly two) of the five cases of bilateral anterior-segment blindness encountered. The prevalance of Bitot spots and vitamin-A-related corneal opacities was 5.3 and 3.2 per 10,000, respectively. There are an estimated 43 new surviving cases of vitamin-A-related corneal opacities in the country each year, one third of which result in bilateral blindness. Fifteen percent of all children examined had grossly purulent conjunctivitis.


Mass distribution of vitamin A and the prevention of keratomalacia.

A retrospective review of 3,490 adminissions to the major pediatric facility in El Salvador was undertaken to determine whether biannual administration of massive doses of vitamin A (200,000 international units) to all availabel 1- to 4-year-old children was effective in preventing keratomalacia. During the 12 months preceding and following initiation of the program, the number of children admitted with presumed vitamin-A-related corneal destruction (33 vs. 31) and proportion of all malnourished admissions with such destruction (26 vs. 25 per 1,000) were similar. The seasonal distribution of these cases remained unchanged, the usual summer peak closely following the first distribution. Unexpectedly, 48% of the children had been ineligible for participation in the program, the vast majority being under 1 year of age. Only 80% of eligible children had actually received the vitamin. Corneal destruction was invariably accompanied by severe, generalized malnutition. Mortality among girls with corneal destruction (28 per 1,000) was almost three times that of boys, or malnourished patients as a whole.


Temporary blindness after cosmetic blepharoplasty.

A patient who underwent a cosmetic blepharoplasty suffered a retrobulbar hemorrhage with no light perception deception detected when the dressing was removed two hours postoperatively. Opening the incision site led to the complete return of visual acuity and ocular motility and relief of the proptosis. The rebleeding of cauterized blood vessels may have caused the retrobulbar hemorrhage and seems to be a potential problem in all cosmetic blepharoplasties. Eliminating the use of postoperative bandages may prevent blindness after cosmetic blepharoplasty since it allows early detection of a retrobulbar hemmorrhage. This allows the nurse to check the patient for loss of vision and proptosis at ten-minute intervals for the first two hours after surgery so immediate treatment can be implemented if retrobulbar hemorrhage and central retinal artery occlusion occur.


Simplified no pressure eyelid retractor for cataract surgery.

A simle, inexpensive, individual, solid blade eyelid retractor has not contact with the globe, produces no pressure on the globe, and eliminates the eyelashes from the operating field.


Ocular findings in Niemann-Pick disease.

Light and electron microscopic studies of the eyes of a 3 1/2-year-old girl who died of Niemann-Pick disease disclosed accumulation of intralysosomal lipid material in all cells other than those that were pigmented. The nonpigmented layer of the ciliary process and the ganglion cells of the retina were especially involved. Electron microscopy revealed two main types of lipid cytosomes. The presumptive explanation for this finding is that the metabolism of the stored material in neurons differs from that in other cells. Topographic and structural studies of the pathologic pigment epithelium suggested that pigmented cells show storage material either when they are in intimate contact with affected cells or when the enzyme defect interferes with the catabolism of the outer segments.


Suppressive processes in binocular vision: ocular dominance and amblyopia.

Recent suggestsions linking suppression observed in amblyopia ex anopsia with that manifested in normal ocular dominance coordinations were experimentally tested. Training procedures which normally alleviate functional amblyopic suppression were shown to have similar results in alleviating the suppression of the nondominant eye in visually normal observers. Methodological and theoretical implications of these results are discussed.


The subjective quality (SQF) of Bausch and Lomb SoflensTM.

The visual acutiy of a person is examined in terms of his response to a unique target. This target is a sequence of black bars on a white background, where the spacing of the bars and their width is governed by a log periodic function. The generation of these targets is performed by a PDP-8 computer connected to an  X-Y plotter. There are six sets of bars which vary in contrast and frequency. In a clinical situation, an observer notates the position where he can no longer resolve the bar pattern. A recroding of these positions produces a Subjective Quality Function (SQF) curve for the individual. On fitting with soft contact lenses, a new SQF curve is generated. A comparison of the SQF for soft lenses with that for spectacle corrections is given.


Complex binocular interaction and other effects in the visual evoked response.

One article dealing with some of the research on binocular interaction effects being carried out in our laboratory has appeared previously in this Journal (White and Bonelli). In that study, it was found that the amplitude of the visually evoked cortical potential (VER) produced by patterned stimuli viewed with both eyes was directly related to the quality of the retina image. Furthermore, the degree of binocular summation shown by the VERs was also related to image quality, with marked summation occurring when sharply focused patterns were presented but much less evidence of it when the patterns were blurred. In that study the retinal images were reasonably similar, since the degree of blur desired was produced by placing ophthalmic lenses of equal strength before the two eyes. The next situation we decided to test was that in which the images presented to the two eyes were not of the same quality. This paper will deal briefly with some work we have done on that topic, and will also present some other examples of work dealing with binocular interaction and related topics.


The psychological differentiation of male myopes and nonmyopes.

A comparison of 140 male myopes and 118 male nonmyopes of the entering class of Virginia Military Institute cadets in 1968 demonstrated that there are a number of Strong Vocational Interest Inventory test items which will clearly differentiate myopes from nonmyopes so that it is possible to identify 76% of the individuals falling into either class on the basis of a stepwise discriminant analysis based almost entirely on the Strong Vocational Interest Blank. The items which discriminate in favor of the myopes are essentially those which require academic achievement and individual creative performance, whereas the items which are in favor of the nonmyopes are those which require business and selling skills as well as outdoor types of activities. Further, the myopes are significantly more likely to achieve officer status and win more academic awards than the nonmyopes.


Deposits on hydrophilic lenses: differential appearance and clinical causes.

Deposits on hydrophilic lenses are classified as to appearance and etiology. One readily identifiable type results from using nondistilled water to ascepticize the lens while another is the result of tear film components not properly cleaned off the lens. Clinical inspection can differentiate the types and aid in preventing reocurrence.


Ocular manifestations of systemic diseases.

The purpose of this review is to keep the optometrist informed as to the latest developments in the field of Ophthalmology. Papers reviewed are, almost exclusively, those published between Oct. 1st, 1973 and Sept. 30th, 1974. Emphasis will be placed on signs and symptoms of the disorders which are helpful in their detection or confirmation. No rare disorders will be discussed and although the literature has been especially rich in single cases this past year, they have been, for the most part, omitted from this review. Thus, to an ophthalmologist, the selection may appear arbitrary and incomplete. For purposes of reviewing, as in previous years, diseases reviewed are divided into non infectious and infectious. Infectious diseases are grouped according to the organ system or the system function predominantly affected, including hereditary and/or congenital diseases. The infectious diseases are grouped as to the causative pathogenic organism.


Possible adverse effects from local anesthetics and the treatment of these reactions.

Adverse drug reactions are potentially serious and are becoming increasingly common. Although optometrists employ only a limited spectrum of drugs they may encounter such reactions among their patients. There is always a risk that a life threatening situation will develop in a pateint quite apart from the use of any drugs. An optometrist as a member of the health-care team must be competent to provide first-aid if an emergency occurs. Tables are provided listing possible reactions to topical anesthetics with the usual signs and the preferred treatment. Optometrists are reminded that many of these treatments are the responsibility of physicians. Optometrists should be prepared to provide artificial respiration and external cardiac massage and should plan in advance how they will obtain additional assistance if an emergency occurs in their office.


Critical flicker frequency and the Pulfrich phenomenon.

The critical flicker frequency and the Pulfrich stereophenomenon were both used to investigate the long term effects on temporal resolution and visual latency of wearing a tinted lens in front of one eye for a period of five days. The results obtained from three subjects showed that in every case the critical flicker frequency was depressed by the tinted lens and displayed no adaptive recovery, but the Pulfrich effect displayed a reduction of apparent depth in the median plane indicating the presence of an adaptive recovery. It is postulated that the CFF indicates that the physiological transmission of the visual signal is unaltered over the the five days and the Pulfrich adaptation occurs due to an alteration of the interpretation of the unchanged visual response. That is, the adaptation is a perceptual rather than a physiological one.


Bifocal control of myopia.

Forty-three native American bifocal wearers grouped by yearly age levels from 9 to 15 with a mixed group of 6 to 8 year olds are matched on beginning age, sex, beginning refractive error and ending age with 83 Native American control subjects. Similarly 226 Caucasian bifocal wearers are matched on the same criteria against 192 control subjects. Although the comparisons are made on each age group, the average annual rate of progression for the bifocal Native American subjects is -0.12 and -0.10 diopters in the right and left eyes respectively against a comparable rate of progression of -0.38 and -0.36 diopters for the control subjects. These differences are significant but not as significant as those found on the Causcasian subjects of -0.02 and -0.03 diopters right and left eyes against -0.53 and -0.52 diopters for the controls.


An alternative to the Drop Ball Test for the measurement of ophthalmic glass fracture resistance.

The Drop Ball Test (DBT) has some distinct disadvantages both as a standard measurement for ophthalmic lens fracture resistance and as a research tool. The Static Test (ST) was devised to allow a load and enzrgy analysis of the DBT and enable more rapid and accurate testing of large ophthalmic lens samples. It was found that over 50% of the energy generated in the DBT is absorbed by the lens mount instead of the test lens. This means that the standard DBT height of 50 inches is more an indication of DBT components than lens fracture resistance. Static testing of non-tempered, heat tempered and chemically tempered lenses correlated well with former DBT studies. The ST, however, allowed lens fracture resistance to be represented in pounds-load, a value better understood practically and mathematically.


Primary health care - the role of optometry.

Optometrists, like all health care providers, should emphasize primary or preventive care. To provide this care optometrists must be aware of the risk factors for major causes of mortality. As an example, the risk profile for a white male age 45 to 49 years is given and discussed. Suggestions for primary vision care and detection of major risk factors by optometrists are also presented.


Functional asymmetries of the human visual system as revealed by binocular rivalry and binocular brightness matching.

Two techniques, a binocular rivalry task and a binocular brightness matching task, were designed to yield indices of asymmetry (relative dominance weights) for the two eyes, the crossed and uncrossed visual pathways, and the two cerebral hemispheres. Twenty subjects with normal vision were run on all conditions. Intercorrelations of the dominance weights obtained by the two methods showed no relationship between the two methods, but produced three hypotheses about visual functioning: (1) the left hemisphere appears more dominant for rivalry; (2) the right hemisphere appears more dominant for brightness matching; (3) the uncrossed visual pathways are dominant over the crossed pathways in the binocular rivalry task.


Hydrophilic lens effects on central and peripheral corneal thickness and corneal topography.

Hydrophilic lens wearing causes an almost evenly distributed central and peripheral corneal thickness increase which  is virtually eliminated when gas of 100% oxygen tension is passed over the anterior corneal surface. There is little corneal topography change associated with this thickness increase.


Variation of visual acuity with soft contact lenses: a function of luminance.

The relationship between visual acuity and luminance with soft contact lenses, compared with the same one obtained with glasses or the naked eye, shows that acuity decreases at the same rate as luminance is reduced. This result differs from what had previously been found in comparing acuity with hard contact lenses and glasses. In the present case, soft lenses conform to the aspherical curvature of the cornea, and therefore the eye wearing soft contact lenses is not  affected by spherical aberration, as in  the case of hard contact lenses. At the outset, soft lenses produce a somewhat lower visual acuity but with adaptation, acuity improves and becomes equal or better, as evinced by measurements made after three months of wear.


Bifocal contact lenses today.

Bifocal contact lenses produced today are far from perfection; however, there are several different types produced, one of which should work out for most presbyopic patients who can be successfully fit with single vision contact lenses. This paper looks at the products we have available now. It is not designed to be a cookbook that the optometric practitioner can follow from A to Z and come up with the ideal contact lens bifocal fit. It is pointed at making the optometrist aware of the growing population of contact lens wearers that the health professions are now creating, and a resume of the products and fitting techniques now available to the eye care field.


Computerized analysis of the image quality of the human eye with optical aids.

Spot diagrams are computer generated by skew ray tracing for a model of the human eye which is corrected by means of a contact lens and spectacle lens. An examination of the images of a point source of light at 0 degrees and 20 degrees off the optical axis of the eye-lens system are shown. For the correction of aphakia, the performance of the contact lens is shown to be superior in off-axis optical performance.


Visual resolution in congenital pendular nystagmus.

For all cases of idiopathic congenital nystagmus visual acuity is reduced. This paper describes the analysis of such a system using some psychophysical methods of evaluation. Both the pattern and movement detecting responses are considered and discussed. Both of their sensitivities are found to be reduced by equivalent amounts. Future studies are outlined.


The endpoint of laser speckle pattern meridional refraction.

Motion of the speckle pattern observed by an ametrope viewing laser light reflected from a rotating cylinder with a matte surface is discussed. Mathematical expressions are derived for the apparent speed and direction (angular velocity) of the pattern when spherical neutralizing lenses are put in place and conditions for an endpoint appropriate for meridional refraction are discussed.


The effects of external ocular irritation on intraocular pressure.

Riot control agents (tear gases) cause intense eye irritation and reflex squeezing of the eyes. The intraocular pressure under these circumstances is unknown but animal and human studies of ocular irritation and forces acting upon the eye indicate a transient increase in intraocular pressure which is not necessarily detrimental to vision.


The design and prescription of multifocal lenses for civil pilots.

The aging (presbyopic) pilot has difficulty with near vision which can be a serious problem in the cockpit because of the complexity and uniqueness of his visual tasks. Numerous individual studies have been reported, but the aviation industry and vision care professionals do not have available to them a set of guidelines to permit the optimum fitting of spectacles for civil aviation pilots. In this study the cockpit vision environment was studied in ten contemporary aircraft. Twenty-five pilots of seven of these aircraft types participated in a spectacle design study. Experimental spectacles were designed for each pilot and evaluated for performance. Problems of pilot acceptance of reading aids, custom designing to the geometry of a given aircraft, balancing of the visual gains from complex designs versus difficulties in use and manufacture have been analyzed. Results of this study should be of value for human factors engineering, vision testing and accurate prescription for the presbyopic pilot.


Errors in space perception due to accommodative retinal advance.

Accommodative retinal advance may be defined as the forward shift of the entire retina from contracture of the ciliary muscle in accommodation. The anterior border moves forward 0.5 millimeters at maximum accommodation, with an asymmetrical distoriton of the image of space. It is as though the retinal image is projected on a thin sheet of rubber pulled out on three sides, the fourth being fixed by attachment to the optic nerve. Accommodative retinal advance explains some puzzling errors of space perception described in dozens of papers and monographs, usually attributed to unequal crowding of retinal receptors, or the mystical upper cerebral activity. The horopter error, the alley error, and the Aubert-Foerster phenomenon are discussed. Credit is given to those early experimenters whose theories have been confirmed.


Myotonia and block of chloride conductance by iodide in avian muscle.

Immature chickens and adult pigeons whose drinking water contained 3% KI for 1--10 days developed myotonia, characterized by stiffness on sudden movement and abnormal repetitive firing of skeletal muscle fibers. Component resting membrane conductances, excitability, and membrane potentials of biventer cervicis muscle fibers from adult pigeons were measured in vitro at 38--39degreesC. Fibers from iodide-treated pigeons in normal solution and fibers from untreated pigeons in I--containing solution (15--120 mM) responded repetitively to electrical and mechanical stimulation. Resting anion conductance (Ganion), assumed to be the sum of C1- and I- conductances, of fibers from iodide-treated pigeons decreased nonlinearly from 2,565 to 266 mumho/cm2 when the bath concentration of I- was increased from 0 to 120 mM. Potassium conductance was assumed constant at 577 mumho/cm2. Ganion of fibers from iodide-treated pigeons was 50% of control and equaled that of untreated fibers in 15 mM I- containing medium. Reduction of the stabilizing Ganion and increased mechanical responsiveness can account for the iodide-induced myotonia in birds.


Microvascular control in intestinal mucosa of normal and hemorrhaged rats.

The mucosal microcirculation in innervated and denervated small intestine was studied using anesthetized rats. Denervation did not cause significant (P greater than 0.05) diameter changes in the precapillary vasculature; however, venules did constrict significantly. These results indicate minimum neural control in the precapillary vasculature during the resting state. The innervated precapillary vasculature constricted during both the carotid occlusion reflex and hemorrhagic hypotension. The diameter of the denervated precapillary vasculature was unchanged during the carotid occlusion reflex and dilated during hemorrhage. The responses of innervated and denervated precapillary vasculatures were attributed to increased neural activity and autoregulatory mechanisms, respectively. Neither innervated nor denervated venules responded during the carotid occlusion reflex. During hemorrhage, however, innervated venules constricted and denervated vessels dilated. The vasoconstriction of the innervated vasculature during hemorrhage contributed to a stoppage of blood and epithelial detachment; these responses did not occur in the dilated, denervated vasculature. Therefore, neural vasoconstriction, qualitatively similar to that in normal animals during the baroreceptor reflex, is a contributing cause to the vascular and tissue impairment in the intestinal mucosa during hemorrhage.


Induction processes in blood-brain transfer of ketone bodies during starvation.

Fed and starved rats were studied on successive days during a 5-day starvation period. The ability of ketone bodies to pass the blood-brain barrier was estimated by single common carotid injections of labeled ketone bodies and water, and results were expressed as the ratio between the normalized activities of tracers in tissue and blood, the brain uptake index (BUI). BUI of D-3-hydroxybutyrate and acetoacetate decreased as their total concentrations increased in the injectate bolus: BUI of D-3-hydroxybutyrate decreased significantly from 8% at 0.2 mM to 3--4% at 20.2 mM in fed rats and from 11.5% at 0.2 mM to 6% at 20.2 mM in starved rats, indicating saturation of the uptake mechanism. The BUI of both ketone bodies increased significantly with increasing duration of starvation, indicating adaptation to ketonemia. Enzymatic kinetics explained the uptake behavior of D-3-hydroxybutyrate in both fed and starved rats and involved a rise of Km and Vmax during starvation consistent with a doubling of the transport rate at the degree of ketonemia found in starved rats. The uptake of glucose was not influenced by starvation or ketonemia.


Effect of parathyroid hormone secretion on sodium reabsorption by the proximal tubule.

To determine if an increase in the endogenous secretion of parathyroid hormone could decrease sodium reabsorption by the proximal tubule, the ionized calcium concentration of blood perfusing the parathyroid gland of eight unilaterally thyroid parathyroidectomized dogs (TPTX) was reduced by infusion of an isotonic sodium citrate plus sodium chloride solution into the blood supply of the parathyroid gland. The fractional clearance of phosphate increased significantly (+9.3 +/- 2.8 ml/min per 100 ml GFR), while fractional sodium reabsorption by the proximal tubule decreased (-.06 +/- .02; P less than .025). In seven normal control dogs that received isotonic sodium chloride infusion, neither fractional sodium reabsorption by the proximal tubule nor the fractional clearance of phosphate was significantly altered. In five bilaterally TPTX dogs that received a sodium citrate plus sodium chloride infusion, sodium reabsorption by the proximal tubule was not significantly altered. There were no significant changes in glomerular filtration rate or renal plasma flow in any of these groups. The data demonstrate that alterations in endogenous parathyroid hormone secretion can play a significant role in the regulation of sodium reabsorption by the proximal tubule.


Electric pacing of intact and transected canine small intestine and its computer model.

In 10 conscious, fasted dogs with electrodes chronically implanted on the intestine, current pulses (8 mA, 50 ms) at frequencies the same as, or faster than, that of the natural intestinal pacemaker always entrained pacesetter potentials (PP) along the proximal frequency plateau, but not along the distal frequency gradient. As duodenal PP's were paced faster, the proximal plateau shortened by orad extension of the distal gradient. Entrained PP's propagated orally and aborally. Their velocity slowed caudally while varying inversely with their frequency. After midduodenal transection had reduced the frequency of the natural PP's distal to the cut, pacing entrained PP's in all areas of the bowel and restored the proximal plateau and distal gradient. But no area could be paced faster than before transection. PP's were not propagated across sites of transection. A digital computer model of coupled relaxation oscillators gave similar results. We conclude that the frequency of the natural pacemaker and the declining gradient of maximal driven frequency determine the frequency pattern of the small intestinal PP.


Ionic requirements of proximal tubular sodium transport. I. Bicarbonate and chloride.

Simultaneous perfusion of peritubular capillaries and proximal convoluted tubules was used to study the effect of varying transepithelial ionic gradients on ionic fluxes. Results show that net sodium influx and volume flux was one-third of normal when bicarbonate was absent, no chloride gradient existed, and glucose and amino acids were absent. Addition of bicarbonate to the luminal fluid did not restore the flux to normal, but peritubular bicarbonate did restore it. A chloride gradient imposed when no bicarbonate was present could only increase the fluxes slightly, but his flux was significant even after cyanide had poisoned transport. Reversing the chloride concentration gradient decreased the net sodium and volume fluxes whether bicarbonate was present or not. Glucose had no effect on fluxes, but substitution of Na by choline abolished them entirely. It is concluded that sodium is actively transported, that a chloride concentration gradient from lumen to plasma could account for up to 20% of net transport, and that peritubular bicarbonate is necessary for normal rates of sodium and fluid absorption.


Distal tubular tracer microinjection study of renal tubular potassium transport.

Renal tubular potassium (K) transfer was studied in rats using a tracer microinjection technique in which [14C]inulin and 42K were simultaneously injected into early distal tubules during osmotic diuresis. Experiments were carried out in 1) animals on a control diet, 2) animals in which K secretion had been stimulated (high-K diet + KC1, Na2SO4, Diamox infusions), and 3) animals in which K excretion had been reduced by a low-K or low-Na diet or by amiloride. 42K excretion into the urine coincided closely in time with the excretion pattern of [14C]inulin. Efflux of 42K out of the lumen was stimulated during reduced K secretion along the distal nephron and decreased during enhanced K secretion when small tubular K loads were given. These experiments demonstrate bidirectional K movement across the distal nephron and show that changes in reabsorptive K efflux participate in the regulation of tubular net K movement.


Energy metabolism in kidney of heat-acclimated hamsters.

Biochemical pathways which are involved in energy metabolism were examined in the kidney of heat-acclimated hamsters. It was found that heat acclimation caused 47% reduction in glucose-6-phosphatase (G1c-6-Pase) activity and 40% lower rate of gluconeogenesis. No changes were found in the activity of hexokinase, glucose-6-phosphate dehydrogenase, pyruvate kinase, lactic dehydrogenase, or in kidney glycogen content. Isolated kidney mitochondria of heat-acclimated hamsters utilized 15% less oxygen than that of controls, but no differences were found in the P/O ratio. Determination of the content of some cytochromes showed a significant reduction in cytochromes c + c1, but no difference was found in the content of cytochromes a, a3, and b. These results suggest that the kidney plays a role in the reduction of energy metabolism during the process of heat acclimation.


45Ca efflux from anterior byssus retractor muscle in phasic and catch contraction.

Phasic or catch contractions in Mytilus anterior byssus retractor muscle (ABRM) were activated by acetylcholine (ACh) and catch relaxation was initiated by 5-hydroxytryptamine (5HT). During phasic contraction and early in catch there is a brief increase in 45Ca efflux. When catch occurs, there is a subsequent drop in 45Ca efflux which then slowly recovers as catch tension declines. With catch relaxation by 5HT there is a biphasic increase in 45Ca efflux, identical to that seen when 5HT is applied to resting muscle. Compartment analyses based on the magnitude of pairs of these responses at varying times of the washout indicated that the increase in 45Ca efflux with activation originates from a compartment with the same time constant as the intermediate (80--100 min) compartment already described by previous resting efflux experiments. The decrease in 45Ca efflux during catch also involves this compartment. The increase in 45Ca efflux with 5HT originates from a more slowly exchanging Ca store with a time constant of approximately200 min.


Net calcium fluxes in anterior byssus retractor muscle with phasic and catch contraction.

Calcium in the artificial seawater bathing whole Mytilus anterior byssus retractor muscles (ABRM) was measured by a specific Ca electrode under various conditions of activation, catch, and catch relaxation. Activation in response to ACh was associated with uptake of Ca by the muscles. Phasic contractions produced a small Ca uptake; catch contractions produced a larger and sustained Ca uptake. After tension relaxation, the muscle lost an amount of Ca roughly equal to that gained. Catch relaxation by 5-hydroxytryptamine (5HT) was associated with Ca release. ACh at identical concentrations, applied to the muscle for increasingly longer times, produced increasing amounts of Ca uptake. Regardless of the previous gain of Ca by the muscle, 5HT applied for a constant interval caused release of the same amount of Ca. A model for the Ca control system in ABRM based on this and previously obtained 45Ca efflux data is proposed.


Temperature and impulse velocity in giant axon of squid Loligo pealei.

Impulse propagation velocity as a function of temperature in the range 5--20degreesC was obtained by external recording from the giant axon of Loligo pealei. The stellar nerve was set into a chamber allowing continuous superfusion, temperature control, and double recording of the impulse. Velocity was calculated from the interval between the spike peaks. The Q10 of velocity was about 1.8. At all temperatures, the velocity increased with time so that only data obtained during the 1st h or 2 could be generally considered to be comparable. Impulse block occurred below --3.4degreesC, in contrast to the giant axon of L. vulgaris, which blocks at about 0degreeC, but at the higher range of temperatures, the velocity in the L. pealei axons was not as well sustained as in those of L. vulgaris. The expected impulse velocity was calculated from Huxley's stability function f(beta) by approximating that function to a fourth-order polynominal and by substituting into it suitable ratios of available Q10 values relating to membrane conductance, ionic current, capacitance, and axoplasmic resistance. The calculation provided an improved fit to published experimental data on L. vulgaris. The difference in slope of the log velocity versus temperature plots, between the presumably warm acclimatized L. vulgaris and the cold-acclimatized L. pealei, was present in both experimental and calculated curves.


Effects of veratrine on repolarization in the canine right bundle branch.

Superfusion of Purkinje fibers in the canine right bundle branch with Tyrode solution containing veratrine, less than or equal to 1 mug/ml, prolonged repolarization phases 2 and 3 and induced a long-lasting negative after-potential that ended in some experiments with a slightly hyperpolarized resting transmembrane potential. The alterations in repolarization time were reversed by washout with veratrine-free Tyrode solution or by adding tetrodotoxin to the veratrine-containing Tyrode solution to a concentration of 0.1 and 1 mug/ml. The effect of veratrine on the repolarization time was more prominent at slower driving rates. Its effect on repolarization of ventricular muscle cells was smaller than that on the repolarization of Purkinje fibers. In the concentrations used, veratrine did not induce multiple responses.


Arterial pressure-flow relations in the awake standing dog.

The transient circulatory changes following paced heart rate increase are reported from 133 trials with 6 unanesthetized dogs with chronically implanted monitoring devices for heart rate, cardiac output, aortic blood pressure, and mean right atrial pressure. In 62 trials with 2 of the dogs, pulmonary artery, and left ventricular end-diastolic pressure, as well as left ventricular dP/dt were also studied. The sequence of changes in pressures and flows is analyzed in terms of probable underlying mechanisms, particularly with respect to the nature of vascular resistances. The rise in aortic pressure and flow during the first 3 s of paced heart rate increase, before arterial stretch receptor reflexes become active, is more consistent with an effective downstream pressure of about 49 mmHg, presumably at the arteriolar level, than with an effective downstream pressure close to 0 mmHg at the right atrial level. In the pulmonary circulation where vascular reflex effects are less prominent, the pattern of pulmonary arterial pressure and flow for the entire 30 s of observation is consistent with an effective downstream pressure of 9 mmHg, presumably at the alveolar or pulmonary arteriolar level, rather than at the level of the left ventricular end-diastolic pressure.


Electrical activity of small intestinal smooth muscle and its temperature dependence.

Some important features of the intracellularly recorded electrical control activity of rabbit jejunal smooth muscle and its temperature dependence are reported in this study. This activity consisted of repetitive 18-mV depolarizations (control potentials (CP) or slow waves), which at 37degreesC lasted 2 s and had a frequency of 18/min and arose from a membrane potential of --55 mV. In some cells periods between CP's exhibited "diastolic" progressive depolarizations (intercontrol-potential depolarization), which may be the trigger of the CP in driving cells. While CP was usually monophasic, some cells persistently exhibited a notch early in the plateau phase. We suggest that CP consists of two components, an "initial depolarization" and a "secondary depolarization," which are usually fused together to give a monophasic potential. Cooling reduced CP frequency and prolonged its duration and caused more cells to show notching. While amplitude and rate of CP initial depolarization had low Q10's, duration and rates of onset and offset of the secondary depolarization had higher Q10's. Thus, the process responsible for secondary depolarization is more sensitive to temperature thant that underlying initial depolarization of the CP.


Electrogenic sodium pumping in rabbit small intestinal smooth muscle.

Oscillations in the activity of an electrogenic Na pump has been suggested as the ionic mechanism underlying the intestinal control potential (slow wave). We investigated the electrogenicity of this pump in rabbit jejunal smooth muscle. Potassium admission to Na-rich tissues caused a large increase in membrane  potential which after 10--20 min decreased toward values comparable with those of normal tissues. This hyperpolarization far exceeded EK and could be prevented by cooling or by ouabain. No hyperpolarization occurred upon K admission to Li-rich tissues in the absence of Na. Thus, the pump in this tissue can operate electrogenically. Goldman's equation was modified so as to account for the pump's contribution to the membrane potential. Using this equation, the calculated contribution of the pump, under normal "steady-state" conditions, is unlikely to exceed a few millivolts. It is concluded that although the pump in this tissue can be electrogenic, its contribution may be smaller than that required if the intestinal control potential resulted from rhythmic turning off and on of the electrogenic Na pump.


Ionic mechanisms of intestinal electrical control activity.

The effects of inhibition and stimulation of the electrogenic Na pump and of altering the ionic environment on the electrical control activity (ECA) were studied in rabbit jejunal smooth muscle. Pump inhibition abolished the ECA at a time when the membrane potential was more negative than the peak depolarization of the control potential (CP). Pump stimulation hyperpolarized the membrane and CP's appeared. Their amplitude was initially small and progressively increased as the hyperpolarization subsided. Lowering external Na to 20 mM or Ca withdrawal, but not addition of verapamil, reversibly abolished the ECA. Chloride replacement by propionate, isethionate, or benzene-sulphonate caused a transient augmentation, followed by suppression of the secondary depolarization of the CP's and decreased their frequency. The initial depolarization of the CP was little affected. Nitrate substitution increased CP frequency and spiking activity but had no observable effects on the CP configuration. These results suggest that the intestinal control potential may result from conductance changes initially to Na and later to C1 rather than fron an oscillatory electrogenic pump.


Interaction between octapeptide-cholecystokinin, gastrin, and secretin on cat gallbladder in vitro.

Effects of OP-CCK, gastrin, and secretin were studied on isometric tension development in strips of cat gallbladder. Effective molar concentrations were 2.2 X 10(-10) to 5.3 X 10(-9) for OP-CCK, and 1.13 X 10(-7) to 1.5 X 10(-6) for gastrin. The maximal response to gastrin averaged 66% the maximal response to OP-CCK and effects were not blocked by atropine. Secretin was weakly stimulatory or ineffective by itself. Prior addition of submaximal doses of gastrin shifted the dose-response curve of OP-CCK to the right, but neither the slope nor the calculated maximal response (CMR) was significantly changed. This suggests that gastrin and OP-CCK compete for a common receptor on cat gallbladder. On the other hand, a background dose of secretin shifted the dose-response curves for both OP-CCK and gastrin to the left and increased the slopes significantly with increase in the respective CMRs. The combined action of OP-CCK (or gastrin) and secretin are supra-additive. These experiments suggest that OP-CCK and gastrin act at a common receptor site which is different from the secretin-receptor site.


Effect of ethanol on phospholipid metabolism by the rat lung.

Prefeeding of alcohol shows the in vivo incorporation of orally administered palmitic acid into phosphatidylcholine of the lung. This impairment is also demonstrable in vitro utilizing lung slices and 14C-labeled palmitate or cytidine 5'-diphosphocholine as precursors. It is concluded that alcohol ingestion affects the utilization of precursors needed for phospholipid formation in the lung.


Renal adaptation to chronic hypocapnia: dietary constraints in achieving H+ retention.

Previous studies suggested that renal H+ retention during adaptation to hypocapnia might be critically dependent upon concomitant Na and/or K excretion. To test this hypothesis, seven dogs were allowed to recover from hypocapnia while receiving a low electrolyte diet. Despite negligible changes in Na and K excretion, cum delta net acid excretion was --33 meq during adaptation and +44 meq during recovery. Consequently, plasma [HCO3] fell from 19.2 to 14.2 meq/liter in the former and rose from 13.8 to 19.7 meq/liter in the latter groups; these changes were virtually identical to those observed previously in animals maintained on normal electrolyte intakes. These adaptive changes in renal H+ output appeared to be balanced by parallel changes in phosphate excretion. When phosphate retention was prevented during adaptation with Na remaining available for excretion, retention of H+ was still clearly evident. When both phosphate retention and augmented cation excretion were prevented during adaptation, however, H+ retention was abolished. Nevertheless, plasma [HCO3] still fell from 20.9 to 16.2 meq/liter, a level far beyond that attributable to tissue buffering.


Quantitative aspects of insulin secretion and its hepatic and renal removal in sheep.

The secretion of insulin into the portal blood and its removal by the liver and kidneys in conscious fed sheep were determined by simultaneously measuring venoarterial plasma concentration differences and portal, hepatic, and renal plasma flows. The basal secretory rate of insulin was 0.43 +/- 0.03 U/h or 7.8 mU/kg-h. The secretory rate of insulin and the amount of insulin presented to the liver also were altered by 2-h intraportal infusions of glucagon (150 mug/h), insulin (1.17 U/h), and insulin (1.17 U/h) lus glucose (2.2 g/h). Hepatic removal under all conditions was about 50% of the insulin secretory rate, although the extraction ratio was only 0.08. Renal removal was 35% of the insulin secretory rate. The renal extraction ratio was 0.35. During insulin-induced hypoglycemia and also during starvation, the hepatic extraction ratio of insulin increased significantly, but the removal as a percentage of insulin secretion did not change. It appears that in sheep on a maintenance diet the basal secretory rate of insulin is less than that of nonruminant species and that, within physiological limits, the liver disposes of about one-half and the kidney about one-third of the insulin. Other tissues, presumably, remove the remaining 10--20%.


Effects of glucagon and insulin on net hepatic metabolism of glucose precursors in sheep.

The net hepatic metabolism of amino glycerol, lactate, and pyruvate was determined in conscious fed sheep by multiplying the venoarterial concentration differences by the hepatic blood or plasma flow. In each experiment several sets of control blood samples were taken; glucagon or insulin then was infused intraportally for 2 h during which additional samples were taken. Four types of experiments were performed: 1) glucagon infusion (150 mug/h) into normal sheep, 2) glucagon infusion (100 mug/h) into insulin-treated alloxanized sheep, 3) insulin infusion (1.17 U/h) into normal sheep, and 4) insulin plus glucose infusion (12.3 mmol/h) into normal sheep. The second group of experiments was performed to prevent reflex hyperinsulinemia, and the fourth was performed to prevent reflex hyperglucagonemia. Glucagon directly stimulated the net hepatic uptake of alanine, glycine, glutamine, arginine, asparagine, threonine, serine, and lactate. Glucagon also stimulated lipolysis in adipose tissue. Insulin, on the other hand, appeared to have a lipogenic effect on adipose tissue and to stimulate directly the uptake of valine, isoleucine, leucine, tyrosine, lysine, and alanine only at extrahepatic sites. The study showed that, in sheep, the effects of glucagon primarily are on liver, and insulin's effects primarily are on skeletal muscle and adipose tissue where it promotes protein and lipid synthesis.


Hypothalamic modulation of baroreceptor afferent unit activity.

Unit responses to sinus nerve stimulation were recorded in the medulla. A conditioning stimulus to the posterior hypothalamus produced inhibition of 65% of unit responses to sinus nerve stimulation as early as 7 ms and extending as long as 790 ms after conditioning; 50% recovered after 300 ms. Unit responses to hypothalamic stimulation alone were also recorded in the medulla, some in the same loci as other unit responses to sinus nerve stimulation. They could be activated by contralateral as well as ipsilateral hypothalmic stimulation and showed recurrent bursts of firing over a 1,000-ms poststimulus interval. Evoked potentials and unit responses were recorded in the posterior hypothalamus, some occurring within 10--20 ms poststimulation of the sinus nerve, indicating that baroreceptor information is ascending in a time sufficiently short to involve the hypothalamus in reflex regulation of blood pressure as well as more generalized homeostatic responses which include the cardiovascular system.


Effect of secretin and cholecystokinin on small intestinal blood flow distribution.

The relative blood flow distribution within the small intestine of anesthetized cats was investigated during resting conditions and when superior mesenteric blood flow was increased 15--85% by the intravenous infusion of secretin, cholecystokinin (CCK), or isoproterenol. Radioactive microspheres of 15 mum diameter were injected into the superior mesenteric artery and shortly thereafter intestinal segments were removed and dissected into mucosal, submucosal, and muscularis fractions. Tissue weights and the radioactivity of each were determined. During secretin-induced mesenteric vasodilatation there was a significant redistribution of blood away from the jejunal mucosa to the submucosa. During CCK and isoproterenol infusions there were significant increases in mucosal and decreases in submucosal blood flow. No significant changes were observed in muscularis flow. There was no apparent relationship between the percent increase in SMBF and the relative blood flow distribution changes observed. The results indicate that while secretin, CCK, and isoproterenol increase superior mesenteric blood flow, they also affect blood flow distribution within the mucosa and submucosa.


Pressure dependence of the mechanical properties of arteries in vivo.

Simultaneously measurements of intra-arterial pressure and external diameter were recorded from the thoracic and abdominal aortas, the carotid, brachiocephalic, left subclavian, and femoral arteries of anesthetized dogs. Data were recorded under control conditions and during efferent vagal stimulation, and were used to compute values of wall geometry, mechanical properties, phase velocity, and characteristic impedance. Values of these parameters computed for both control and vagal stimulation were used to represent their dependence on mean arterial pressure. Both the dynamic elastic modulus and the phase velocity increased with mean pressure at each arterial site. Values of computed characteristic impedance were constant and independent of mean arterial pressure between 80--150 mmHg. The tropical application of norepinephrine (100 mug/ml) to the femoral artery produced no change in mean pressure, while external diameter and dynamic modulus were decreased, and characteristic impedance was increased. These results provide direct support for the conclusion of previous studies on vascular impedance spectra which suggested a constancy of characteristic impedance with changes in mean arterial pressure.


Effects of carotid hypotension on aortic hemodynamics in the unanesthetized dog.

The effects of occlusion of the brachiocephalic artery on aortic hemodynamics were assessed in 12 chronically instrumented dogs in the unanesthetized state. Continuous measurements of ascending aorta pressure and flow were made. In the steady state following occlusion, heart rate increased by 36% and mean arterial pressure by 45%, while cardiac output was unchanged from preocclusion levels. Hydraulic power delivery to the systemic circulation by the left ventricle was increased during occlusion, while the fraction of total power associated with pulsations decreased. Values of peripheral resistance and ascending aorta input impedance were both increased during occlusion. Graded occlusions of the brachiocephalic artery produced graded, monotonic increases in the entire aortic impedance spectrum between 2 and 20 Hz with more sensitive responses occurring with the smaller, submaximal responses. Considered with results of previous studies, these results suggest that activation of smooth muscle in large conduit arteries is also associated with the pressor response which accompanies carotid hypotension and that such activation has a hemodynamically significant effect.


Hematocrit of the fetal rabbit placenta.

51Cr-labeled erythrocytes and [125I]RISA were used simultaneously to measure the fetal rabbit whole-body and placental hematocrits (Hct) and to find the ratio of placental transit times of erythrocytes and plasma. The levels were injected into the heart of 21 fetal rabbits of 26--28 days gestation, and about 60 s mixing time, the placenta and a fetal blood sample were assayed with a gamma well-type scintillation counter. Erythrocyte and plasma activity per milliliter were determined from a standard dilution of the isotopes. Large-vessel Hct was measured as the corrected packed erythrocyte percentage in capillary tubes. Large-vessel Hct was 37.3 (+/- 3.7 SD) %, whole-body Hct was 31.3 (+/- 3.5) %, and the placental Hct was 25.3 (+/- 4.0) %. The placental/large-vessel Hct ratio was 0.676. The ratio may be estimated as 0.765 when corrected for the loss of albumin in time. The transit time of erythrocytes in the placenta was calculated to be 0.682 of that for plasma. The shorter erythrocyte transit time implies that there is less time for O2 and CO2 exchange than previously thought.


Development of circadian periodicity in base and stress levels of corticosterone.

Base and stress levels of corticosterone were assessed at 4-h intervals over a 24-h period in male and female rats at age 18, 22, and 26 days. A significant periodicity in base levels of corticosterone is present at 22 days of age; however, a rhythm in stress values does not appear until age 26 days. At age 26 days the pattern of the circadian periodicity in both base and stress concentrations of corticosterone resembles that of the mature rhythm.


Sweating on paws and palms: what is its function?

Man sweats on his palms and the soles of his feet in response to stress and exercise, but not in response to heat. Several functions have been proposed for this type of sweating: increasing friction between skin and substrate; increasing the toughness of the skin; and increasing tactile sensitivity. This study uses a comparative approach to evaluate the role of footpad sweating on increasing friction, utilizing a variety of mammals which possess sweat glands on their footpads (rat, tenrec, hyrax, and dog). We found that all of these animals sweat on their paws while running. Blocking this sweating with atropine sulfate dramatically decreased the coefficient of static friction between the paw and the tread of an inclined treadmill. A similar dose of atropine sulfate had no effect on the coefficient of static friction in a rabbit, and animal that possesses no sweat glands on its paws. We conclude that an important function of this type of sweating is to help prevent slipping between the paw and sthe substrate during running or climbing, and we postulate that the sweating observed in response to stress may play an important role in preparing an animal for fleeing from stressful situations.


Potassium transport in the distal tubule and collecting duct of the rat.

Because of recent conflicting results, micropuncture studies were performed to clarify the respective role of the distal convoluted tubule and collecting duct in the regulation of urinary potassium excretion. Five groups of Sprague-Dawley rats were studied: group I, hydropenia (n = 10); group II, Ringer loading (n = 7); group III, acute KC1 loading (n = 6); group IV, mannitol diuresis (n = 6); group V, KC1 infusion during mannitol diuresis (n = 7). Early and late distal tubules were identified with intravenous injections of lissamine green. In each animal net secretion of potassium occurred along the distal convoluted tubule, and a direct relationship between distal tubular flow rate and potassium secretion was observed. The magnitude of potassium secretion at high distal tubular flow rates was dependent on the model studied. Potassium transport beyond the distal tubule was evaluated by comparing end distal potassium delivery and fractional potassium excretion. At low urinary flow rates net reabsorption was observed, whereas at higher flow rates no net transport occurred. Thus, flow rate along the collecting duct may be a major determinant of urinary potassium excretion.


Vasomotor inhibition in rabbits by vagal nonmedullated fibers from cardiopulmonary area.

In anesthetized rabbits with sinus and aortic nerve cut, when the cervical vagal nerves were cooled to 12, 8, 6, and 0degreeC, there were progressive increases in aortic blood pressure of 7 +/- 1, 15 +/- 2, 25 +/- 1, and 41 +/- 2 mmHg (SE), respectively. For comparison, during cooling of the aortic and vagal nerves, at 12degreesC there was a decrease in firing in the afferent fibers from aortic baroreceptors (48 +/- 4%) and pulmonary stretch receptors (57 +/- 5%), and at 6degreesC all activity was abolished. Thus, at 6degreesC the activity in medullated fibers from the aortic baroreceptors and pulmonary stretch receptors is blocked, but the increase in aortic blood pressure with vagal cooling is only 60% of that with cooling to 0degreeC. This demonstrates that cardiopulmonary receptors with nonmedullated vagal afferents (C fibers) contribute to the tonic inhibition of the vasomotor center. Because of overlap in sensitivity of different vagal fibers to cooling, the total contribution of these C fibers cannot be evaluated.


Interstitial fluid pressure in canine gastric mucosa.

Guyton's capsules were implanted in the submucosa of the gastric corpus of dogs. The pressure of the fluid inside the capsule (ICP) was measured between 12 and 42 days later after mounting the piece of the corpus in a Plexiglas chamber. The capsule was always filled with saline. In two out of three experiments, the ICP did not change significantly when the saline was replaced by isotonic glucose or blood plasma. Changes of pressure exerted on the surface of the stomach were accurately monitored by the ICP recordings. Changes of circulation produced by compression of the artery or the vein connected to the piece of mucosa, or by intra-arterial injections of epinephrine, norepinephrine, isoproterenol, or hypertonic mannitol, modified the ICP as predicted by Starling's law of capillary filtration. Spontaneous activity of the gastric muscles or the activity, which followed intra-arterial injections of acetylcholine, prostigmine, or histamine, changed the ICP significantly. Intra-arterial atropine usually decreased the ICP by 3--5 mmHg. The mean value of the ICP in 49 animals was 0.53 +/- 0.34 mmHg (SEM); it was negative in 43% of the experiments.


Circadian rhythm of biliary excretion and its control mechanisms in rats with chronic biliary drainage.

Rats with chronic biliary drainage under a rigid lighting schedule (light on at 6 A.M. and off at 6 P.M.) exhibited a remarkable circadian rhythm of bile flow, biliary concentrations and excretory rates of bile salts, cholesterol, and phospholipid. The peak was attained at midnight and nadir at noon except for the peak concentrations of cholesterol and phospholipid occurring at 8 P.M. Cholesterol feeding abolished the circadian rhythm of biliary cholesterol and phospholipid concentrations but not their excretory rates because the daily fluctuation of the bile flow remained unchanged. Bilateral vagotomy enhanced the bile flow rate and shifted the peak of circadian rhythm of all parameters except bile salt 4 h earlier. Bilateral adrenalectomy abolished the circadian variation of the concentration of cholesterol and phospholipid and minimized that of bile salt, but the daily fluctuation of their excretory rates persisted in a lower amplitude. The studies suggested that such circadian rhythm might be controlled simultaneously by multiple factors and could not be entirely abolished by any single special treatment.


Feeding induced by intracerebroventricular 2-deoxy-D-glucose in the rat.

Feeding was induced with lateral intracerebroventricular (ICV) injections of 2-deoxy-D-glucose (2-dg), a glucose analogue causing glucoprivation. Feeding increased rapidly by an average of 2.6 g following ICV 2-DG (2.9 or 5.8 mg per rat), but did not increase after ICV D-glucose or sucrose. At the same doses, 2-DG did not increase feeding when given peripherally. Core temperature dropped in a dose-dependent manner with doses of 2-DG sufficient to induce feeding after peripheral administration, but did not occur with ICV injections. The 2-DG (0.006--1.219 M) did not stimulate feeding when infused bilaterally into the lateral hypothalamus, the preoptic area, or the anterior lateral hypothalamus. Nor did it produce feeding when injected into the ventromedial hypothalamus at the same sites and in the same rats in which procaine HC1 caused increased feeding. The brain, therefore, is directly sensitive to glucoprivation in the control of feeding, and glucoprivation alone is sufficient to mobilize feeding behavior. The specific site of sensitivity to glucoprivation and the mode of action of the glucoprivic system in the brain are unknown.


Hepatocellular uptake of erythritol and mannitol in the dog.

The purpose of this study was to determine the initial space of distribution of [14C]erythritol (mol wt 122) and [14C]mannitol (mol wt 182) in the liver of the dog by the single-injection, multiple-indicator-dilution method. 22Na was used as the extracellular indicator and tritiated water (THO) was used as total liver water indicator. The indicators were simultaneously injected into the portal vein of anesthetized dogs and dilution curves were obtained at the outflow from the hepatic vein. It was found that hepatic venous dilution curves of [14C]erythritol and THO were practically identical in all experiments. In contrast, the dilution curves of [14C]mannitol were generally distinct from those of THO. Analysis of [14C]mannitol-dilution curves according to Goresky suggested that the observed difference between this solute and THO was the result of a limited permeability of the sinusoidal membrane to mannitol. It is concluded that [14C]erythritol has instantaneous and practically unrestricted access to total liver water. This finding supports the validity of using erythritol as a liver cell water marker. A larger solute, [14C]mannitol, has restricted access to total liver cell water because of a permeability barrier in the sinusoidal liver cell membrane, but its diffusion into the hepatocyte is also very rapid.


A psychosocial kinship model for family therapy.

Family therapy has traditionally centered on the nuclear family and thus has been typically oriented toward urban white middle-class families. A variety of modifications in therapeutic technique has evolved for work with the many modern families whose structure consists of a functional psychosocial family kinship. The authors have developed a formal theoretical framework and model for family therapy that encompasses the total psychosocial network, i.e., the extended kinships of the nuclear family and the functional kin such as friends, neighbors, and associates.


Insuring intensive psychotherapy.

Many private insurance programs that currently cover mental disorders eliminate intensive psychotherapies, including psychoanalysis, from the range of treatment options by placing restrictions on the number of visits covered. The authors examine the economics of intensive psychotherapy coverage and present data indicating that relatively few people in an insurance program with comprehensive mental health benefits use high cost forms of psychotherapy. They conclude that insurance coverage of intensive psychotherapy is feasible but suggest that further study of the goals of intensive treatment, potential demand for it, and the supply of qualified practitioners is needed.


Borderline and schizophrenic patients: A comparative study.

The authors describe the evaluation and follow-up of matched samples of borderline and schizophrenic patients to determine the ways that borderline disorders are similar to or different from schizophrenia. The borderline patients presented more confusing diagnostic pictures, but they could be differentiated from the schizophrenic patients by the absence of definite or prolonged psychotic episode, by the relative severity of their dissociative experiences, by more severe anger, and by less anxiety. Despite the discrepant symptom pictures of the two patient groups, a systematic review of prehospitalization functioning and two-year posthospitalization course did not reveal significant differences between them.


Psychopathology and mental retardation: A study of 100 mentally retarded children: I. Psychopathology.

The authors studied 100 mentally retarded children referred to a psychiatric clinic in regard to the severity of their retardation, their ages at the time of referral, their social class, their presenting symptoms and diagnoses, and the effects of organicity on their clinical pictures. They found that 38 of these children were psychotically disturbed, 13 had no evidence of psychiatric disorder, and 49 showed symptoms of characterologic, neurotic, behavioral, or situational disorders. Although the incidence of emotional disorder was high among these children, their symptoms did not differ in kind from those found in a group of nonretarded children referred to the clinic.


Changing patterns of psychiatric inpatient care in a university general hospital.

The authors describe the changing patterns of psychiatric inpatient care in a university hospital. Patients are shortening their hospital stay and are traveling fewer miles from their homes to the hospital. Increasing numbers of blacks, men, and low-income persons are being treated. In addition, the percentage of patients with neuroses and transient situational disturbances has decreased, while the percentage of those with personality and behavior disorders has increased. The authors discuss the implications of these changes, which benefit both patients and the education of students.


A critique of the St. Louis psychiatric research criteria for schizophrenia.

The authors reviewed the research data for 89 hospitalized patients who were given a diagnosis of schizophrenia and 22 who were given a diagnosis of mania on admission. They found that 11 (12 percent) of the schizophrenic patients satisfied the St. Louis research criteria for schizophrenia and 10 (11 percent) satisfied the authors' criteria. Diagnostic agreement between the sets of criteria was shared in only 5 of these patients. On the basis of this finding and other studies of the St. Louis criteria, the authors suggest specific modifications that would broaden the utility of these criteria and minimize diagnostic disagreement.


Prediction of performance of psychiatric residents: A three-year follow-up study.

The authors compared supervisors' global and specific item ratings of psychiatric residents' performance in each of three years of training with ratings of these applicants prior to their admission to the program. Although preadmission ratings had almost no predictive power, there were certain items that consistently discriminated between residents rated high and those rated low by supervisors in each year of training. The authors conclude that initial interviews of those selected cannot predict their subsequent performance. They therefore recommend that a major portion of these interviews be devoted to an exchange of information between the applicant and the department.


Differing perspectives on mental health evaluation.

Small-group workshops of nonevaluators with differing interests in mental health discussed evaluation priorities for community mental health centers. Participants included center professionals, concerned citizens, and funders. A majority of the participants placed high value on accountability from a consumer standpoint and relatively low value on center management issues and cost or equity of service delivery. Center staff were more interested in efficiency and effectiveness, while outsiders with vested interests were more concerned with community involvement. The authors summarize seven role perspectives and discuss their implications for the establishment of evaluation priorities within a center.


On research in Zen.

Zen is one of several mental or spiritual disciplines that have become the object of recent scientific interest and theory. The authors discuss several aspects of Zen, such as the psychophysiological effects of meditation and the general impact of enlightenment, that are potential areas of fruitful research. They stress, however, that researchers can gain true understanding of the different perception and experience of reality to which Zen gives access only by practicing Zen meditation themselves. Without such understanding, the planning and interpretation of research will inevitably be in error and a resource of the greatest potential value misused.


Professional liability insurance and the American psychiatrist.

The authors outline the current position of psychiatrists in the United States regarding their vulnerability to lawsuits for malpractice. They review the various activities of the American Psychiatric Association on behalf of its members, especially its endorsement and supervision of a professional liability program for review and control of losses.


Psychiatry's image today: Results of an attitudinal survey.

The authors report the results of a survey designed to assess opinions and attitudes toward psychiatry among three groups of physicians and two groups of medical students. In general, the role of psychiatry was regarded favorably, and respondents' comments and criticisms were constructive and consistent. The authors suggest that the survey results may reflect an improvement in psychiatry's image.


The treatment of depression with ECT in the presence of brain tumor.

Traditionally, the presence of brain tumor has been considered an absolute contraindication to the use of electroconvulsive therapy. In selected cases, however, this procedure may be beneficial and at times even lifesaving. The authors point to the need for an eclectic approach to treatment, given the current state of psychiatric knowledge.


Organic brain dysfunction as a possible consequence of postgastrectomy hypoglycemia.

Unlike the fasting hypoglycemias, the reactive hypoglycemias, including postgastrectomy hypoglycemia, are generally not believed to result in serious neuropsychiatric dysfunction. The authors describe two patients with progressive mental deterioration and alimentary hypoglycemia and suggest that clinicians should recognize the possibility of serious neuropsychiatric sequelae of postgastrectomy hypoglycemia.


Time estimates in a long-term time-free environment.

Subjects in a time-free environment for 14 days estimated the hour and day several times a day. Half of the subjects were under a heavy exercise regime. During the waking hours, the no-exercise group showed no difference between estimated and real time, whereas the exercise group showed significantly shorter estimated than real time. Neither group showed a difference after the sleeping periods. However, the mean accumulated error for the two groups was 48.73 hours and was strongly related to the displacements of sleep/waking behavior. It is concluded that behavioral cues are the primary determinants of time estimates in time-free environments.


Visual recogition of dot-pattern bigrams: an extension and replication.

The study examined visual recognition of bigrams, each formed from a pair of "random" dot patterns, as a function of stimulus offset asynchrony and duration. The results replicate and extend those of an earlier study by showing that the effect of backward masking in vision, where the mask is actually a part of the preceding composite target, is limited to about 250 to 300 msec. This time interval is suggested as that required to complete the processing of that composite target. The results may be understood in terms of an interruption hypothesis, with selective attention and/or discontinuity detectors as mechanisms possibly involved in the masking process.


Ego strength and confidence thresholds in two methods of paired-associate learning.

Two experiments contrasted the effects of high and low wgo strength (as measured by Cattell's Sixteen Personality Factor Questionaire) on confidence thresholds (FG scores) under the anticipation and recall methods. High ego strength resulted in larger FG scores under the anticipation method- weakly so in Experiment I but significantly so in Experiment II, where subjects were selected from greater extremes of ego strength. This inferiority extended to trails to criterion and a measure of the associative-learning stage as well. Tasks for extending the generality of the obtained relationship of ego strength and confidence thresholds in paired-associate learning are suggested.


Some effects of a model's performance on an observer's electromyographic activity.

It is suggested that motor reactions may be elicited in an observer as a consequence of his exposure to a model and that such reactions may become conditioned to environmental events. An experiment is reported in which observers showed greater EMG activity in the arm while watching models arm wrestle than while watching a model stutter, and greater lip EMG activity while watching a model stutter than while watching arm wrestling. Some evidence for conditioning was found in the arm activity of males watching wrestling.


Aldactazide-induced consummatory and operant responding to sodium by rats.

The effects of intraperitoneal injections of Aldactazide-A on rats' consumption of water and saline solution (.51M NaCl) were tested in two experiments. During the treatment sessions, the rats showed a substantial increase in saline consumption and in lever pressing to a cue light to obtain the saline, as compared with their negligible intake before the injections and after the injections had been discontinued. The results indicate that both the drinkometer and operantbox measures are sensitive to the natroexigenic effects of Aldactazide.


The relation between similarity grouping and perceptual constancy.

In two experiments on whether similarity grouping is based on the retinal or the perceived slopes of lines, observers judged the grouping of diagonal lines when a display of vertical and diagonal lines was presented upright and when it was slanted 75 deg toward the floor. The floorwise slanting of the display improved gouping, as would be expected if the spontaneous organization of a field into groups in strongly influenced by the projection-level representation of stimuli. It is proposed that similarity grouping occurs at the readout stage of stimulus processing and involves segregating a field into groups on the basis of extrafoveal stimulus differences that are responded to in parallel; or if sequentially, very quickly and independently of focal attention.


The number of trials of compound conditioning: its effect on latent inhibition in rats.

Two experiments interspersed nonreinforced tests for the strength of the preexposed and nonpreexposed elements of a compound CS throughout conditioning. The nonreinforced exposures and the conditioning trials were superimposed on an appetitive operant baseline, and conditioned suppression of the rats' bar pressing was the dependent variable. In both experiments, the preexposed element failed to suppress responding and failed to gain strength over trials. The nonpreexposed element at first suppressed responding completely but gradually lost control of responding, even while the compound continued to suppress responding asymptotically. The results are discussed in terms of 'loss of salience' and 'discrimination' hypotheses.


Carbon monoxide in school buses.

Following an incident in which eight children became ill from carbon monoxide in a school bus, an investigation was made of CO levels in school buses in the Seattle area. The procedure selected for the evaluation was to test a large number of buses at a nearby ski resort. On the day selected for the sampling, over 200 buses arrived, bringing school children from a number of school districts in the Seattle are for skiing lessons. As they arrived, 33 buses were checked immediately to determine in-transit levels of CO. Four of the 33 buses had CO levels in excess of Environmental Protection Agency maximum allowable concentrations for an 8-hr exposure. As the buses sat idling in the parking lot, 65 of them were tested--during the lunch hour when the students returned to the buses to have their lunch and to rest. Two buses had nearly 3 times the concentration of CO permitted by the EPA for a 1-hr exposure. A total of seven buses (10 per cent) had concentrations of CO not permitted by the EPA for more than a 1-hr period. Altogether there were 24 buses (36 per cent) that had levels of CO in excess of EPA standards for an 8-hr exposure. As a result of these determinations and other observations a number of recommendations were made to reduce the hazard of exposure to carbon monoxide in school buses.


Superior mesenteric angiography and blood flow following intra-arterial injection of prostaglandin F2alpha.

The effect of intra-arterially administered prostaglandin F2alpha(PGF2alpha) on venous demonstration in angiography of the superior mesenteric artery was compared to that of bradykinin in 10 patients, and the flow increase in this vessel following PGF2alpha was measured by a dye dilution technique in another 8 patients. The angiographic demonstration of veins was similarly improved by the 2 drugs, the effect of 60 mug. of PGF2alpha being roughly equivalent to that of 10 mug. of bradykinin. The loss of arterial detail was less marked after PGF2alpha which, however, had a longer duration of action. The flow studies indicated that 80 mug. of PGF2alpha increased the superior mesenteric blood flow 103 +/- 16 per cent. There was no influecne on blood pressure or pulse rate. The patients experienced a sensation of warmth in the abdomen for a few seconds following the injection of drugs, but no other side effect was noted. It is concluded that PGF2alpha causes a rapid increase of the superior mesenteric blood flow in man making it suitable for pharmacoangiography of this vascular bed.


Limited form of Wegener's granulomatosis in ulcerative colitis.

The limited form of Wegener's granulomatosis is described as a complication in 2 cases of chronic ulcerative colitis. The coexistence of ulcerative colitis and the limited form of Wegener's granulomatosis raises the question of a common etiologic basis, possibly an immunologic defect. Awareness of such an association may help shed further light on the etiology of both disorders.


Pseudo-retroperitoneal gas in rupture of aneurysm of abdominal aorta.

Four cases of ruptured abdominal aortic aneurysm producing retroperitoneal radiolucent shadows are presented. Gross and microscopic examination showed this to be due to dissection of blood through the retroperitoneal fat. This finding has been helpful in confirming the presence of retroperitoneal hemorrhage.


Jejunileal bypass. Roentgenographic observations.

Jejunioleal bypass procedures may be performed with the bypassed small intestine draining, as usual, into the cecum, or with end-to end anastomosis of the jejunum and terminal ileum, with the bypassed segment draining into the transverse colon through another anastomosis. Modifications of these methods have also beed devised. After good response with weight loss initially, most patients fail to continue to lose weight into the third year postoperatively. Some of the features which cause failure are: prolonged transit time, intestinal dilatation with mucosal hypertrophy, and reflux into the bypassed segment, in the earlier type of operation.


Comparative detection of pancreatic body--tail enlargement using the supine translateral and axial pancreatic views: a prospective statistical study.

A prospective statistical study of 429 patients was undertaken to determine if the axial pancreatic view would improve detection of pancreatic body-tail enlargement. This view is produced by directing a roentgen-ray beam along the axis of the pancreatic body-tail cylinder. On this view and on the supine translateral view, a pancreatic body-tail space can be identified as a subdivision of the retrogastric space. When the pancreatic body-tail enlarges, this space selectively enlarges. The percentage change of this space is particularly impressive on the axial pancreatic view, where 10 of 12 pancreatic body-tail neoplasms were detected with only a 1.8 per cent false positive rate.


The significance of thermography in the diagnosis of acute abdominal disease.

Thermography appears to be a useful supporting aid to classical methods of examination in the clarification of the problems of acute abdominal disease. In a study of 100 patients thermography was in support of the true diagnosis in acute appendicitis in 63 per cent, in acute biliary tract disease in 59 per cent, and, in an attempt to differentiate between tumor and periappendicular abscess, assistance was rendered by thermography in 53 per cent of patients. However, some uncertainty exists because carcinoma often produces in its environment an inflammatory reaction, which causes an increase of temperature visible in the thermogram. In the present series thermography produced a finding supporting the correct diagnosis in 59 per cent. Errors occurred most often in obese patients, who have thick abdominal covers. Thermography also has an obvious application in the localizing of postoperative suppurative foci.


New thoughts concerning xanthogranulomatous pyelonephritis (X-P).

A clinical and roentgenographic analysis of 13 patients with pathologically proved xanthogranulomatous pyelonephritis (X-P) has demonstrated that many previously accepted truisms associated with this disease may not be valid. As a result of this study it is suggested that X-P: 1. Does have a prominant female distribution. 2. May arise relatively acutely. 3. Can be associated with a well-functioning kidney. 4. May destroy the kidney and collecting system. 5. Does not demonstrate neovascularity. 6. Can be distinguished angiographically from hypernephroma. 7. May be associated with diabetes. Other important facts were again observed: 1. X-P is still often associated with staghorn calculi and urinary tract obstruction. 2. Proteus mirabilis is the main offending organism.


Practical significance of gastric rugal folds.

A clinical pilot study oriented toward the practical value of gastric fold assessment offers the follow: (1) Younger patients (below 60 years) with carcinomas may have rugose stomachs as opposed to the more usual presentation in the elderly. (2) Some proportionality of gastric fold to acid output may exist in normal patients or cases with peptic disease of the distal stomach or duodenum. In any given case, however, acid secretory capacity may be very broad. (3) Proportionality of fold pattern within the stomach itself or with respect to the duodenum, as noted in the literature, is emphasized. (4) There exists a possible upper limit of "physiologic" fold thickness of 4 to 5 mm. beyond which an additional pathologic process may be inferred. (5) Hypertrophic gastritix and gastric body ulcer disease may illustrate this progression and possibly share similar underlying mucosal pathology and rugal characteristics.


Roentgenographic findings in typhoid fever.

Barium meal examinations have been performed on 20 patients with proved or clinically suspected typhoid fever. There were distinct abnormalities in the terminal ileum early in the febrile stage of the disease. The abnormality was different in a single case of relapse of typhoid. The study is easily and safely performed and we feel that it is a valuable adjunct in the diagnosis of typhoid fever, particularly in those cases where a positive blood culture is not available to confirm the clinical impression. The result of the roentgenographic examination is obtainable immediately and treatment can be initiated early.