Coronary bypass graft fate: angiographic grading of 1400 consecutive grafts early after operation and of 1132 after one year.

All 1400 coronary bypass grafts, in 409 survivors of 414 patients undergoing 440 consecutive bypass operations, were selectively opacified in multiplane cineangiograms prior to hospital discharge and 1132 (81%) were restudied at one year. Grafts were graded A (excellent), B (fair) or O (occluded) by separate assessment of proximal and distal anastomoses and bypass trunks. In early graft studies 89% were patent (A and B), 79% graded A; at one year, 81% were patent, 74% graded A. Circumflex-marginal grafts fared less well early, but similarly late, compared with other grafts. Of all grafts graded B early, 37% became A, 39% remained B and 24% were occluded at one year; 90% of early graded A grafts remained so, 4% became B and 6% occluded; the grading system seems to have had useful predictive value. Distal anastomosis defects dictated early B grading in 81.3% of cases, trunk defects in 12.5% and proximal anastomosis defects in 2.7%. Trunk defects carried a worse prognosis for occlusion than did distal anastomosis defects. Side-to-side, vein-coronary anastomoses had a significantly higher patency rate than terminal end-to-side coronary anastomoses with the same veins.


Effect of digoxin and diuretics on high altitude left ventricular dysfunction.

Systolic time intervals, stroke volume, cardiac output and (dZ/dt)/RZ index were serially estimated in 51 normal healthy volunteers at sea level, for ten days after air induction to 3658 m altitude and on return to sea level. The subjects were divided into three groups and were administered a diuretic, beta methyldigoxin and placebo in a double blind protocol. The group on placebo showed an increase in heart rate, reduction in stroke index and cardiac index during high altitude exposure with normalization on return to sea level. A deterioration in left ventricular function as manifested by prolongation of pre-ejection period, increase in PEP/LVET ratio, reduction in (dZ/dt)/RZ index and left ventricular ejection time was also noted at high altitude. The subjects on digoxin maintained normal stroke/cardiac index and did not show any significant changes in the parameters of myocardial function. The diuretic group showed more deterioration in the parameters than the placebo group. No significant side effects were noted. Left ventricular dysfunction and reduction of stroke index at high altitudes may be causually related; digoxin administration may prevent them from occurring.


Computer-controlled instrument system for sequential chemical testing III. Application to liver assessment.

We used the previously described [Clin. Chem. 19, 1114 (1973)] and evaluated [Clin. Chem. 19, 1122 (1973)] computer-controlled instrument system for sequential chemical testing to select and perform tests of hepatic status, to aid the clinician in the diagnosis of liver disease. Results for total bilirubin, aspartate aminotransferase, and alkaline phosphatase obtained from the continuous-flow analysis (SMA 12/60) admission screen were used by the instrument system to determine selectively the values for gamma-glutamyltransferase, alanine aminotransferase, creatine kinase, and total and direct bilirubin. Kit methods for the latter four tests were evaluated on the system; results were similar to manual procedures. A software, enzymatic ratemeter was found to be better than the previously described hardware ratemeter. The follow-up tests of serum prescribed by the system are compared to clinician-prescribed follow-up tests and discharge diagnoses. In 10 of 19 cases, the system and clinician ordered similar follow-up tests; in three cases follow-up differed, and in six cases, the system ordered follow-up tests and the clinician ordered none.


Comparative determination of phenytoin by spectrophotometry, gas chromatography, liquid chromatography, enzyme immunoassay, and radioimmunoassay.

Sera from patients being treated with phenytoin were analyzed for the drug by spectrophotometry, gas chromatography, radioimmunoassay, enzyme immunoassay, and liquid chromatography. The essay values obtained were intercompared statistically. Enzyme immunoassay and liquid chromatography appear to be attractive alternatives to the more traditional methods of spectrophotometry and gas chromatography. Our radioimmunoassay data correlated poorly with results by the four other methods.


Radioimmunoassay and radioenzymatic assay of a new aminoglycoside antibiotic, netilmicin.

A radioimmunoassay and a radioenzymatic assay for netilmicin, a new aminoglycoside, were developed in our laboratories to assist in the study of the pharmacology of the drug and to establish values for use in its monitoring. The assays are sensitive, precise, and rapid, giving results that correlate (r = 0.90) with each other and with those of a microbiological assay in which Klebsiella pneumoniae is used as the test organism. Preliminary pharmacological studies show the drug to have a biological half-life of 135 min. which is comparable to that for other aminoglycosides.


[Heterogeneity of glycogenosis with alpha-1,4-glucosidase deficiency: enzymatic studies in three families (author's transl)].

The authors describe four cases of atypical forms of glycogenosis with alpha-1,4-glucosidase (acid maltase) deficiency. The results of clinical, microscopic, histochemical, enzymological and immunological studies are described. Acid maltase activity has been studied in muscle, leukocytes and fibroblasts. The authors show no difference in the properties of acid maltase; the authors study the purified enzyme from various tissues.


Anti-drug sera raised by immunisation with a readily available drug-enzyme conjugate.

A phenytoin-enzyme conjugate, readily available as an enzyme-immunoassay reagent, is shown to be a convenient immunogen for production of anti-phenytoin sera for immunoassay purposes.


Thyroid function tests in patients on long-term treatment with various anticonvulsant drugs.

Thyroid function tests were studied in patients undergoing long-term treatment with various anticonvulsant drugs. Previous reports that diphenylhydantoin induces a decrease in the serum concentrations of total and free thyroxine (T4) and triiodothyronine (T3) without a change in the TSH concentration were confirmed. Diphenylhydantoin had no effect on reverse T3. Carbamazepine was also found to decrease serum T4, the free T4 index and T3 but, with the exception of T3, the decrease was smaller than that induced by diphenylhydantoin. Dipropylacetic acid did not influence the serum thyroid hormone concentrations, and neither did primidone. This demonstrates that the interaction between anticonvulsant drugs of different chemical structure and thyroid hormone metabolism is diverse. None of the drugs tested altered serum TSH or the T3 uptake test for the estimation of unsaturated thyroid hormone binding-capacity in serum. These two tests are considered diagnostically more dependable than the measurement of thyroid hormones in serum when diphenylhydantoin and carbamazepine are administered.


Human chromosome preparations obtained from immunoadsorbent separated T- and B-cells.

A modification of immunoadsorbent column separation of T- and B-lymphocytes has been used to obtain karyotypable chromosome preparations. This method may be of some use in helping to gain further information about some mosaic conditions or the chromosome complement of appropriate blood disorders.


The natural antibody response to E. coli includes antibodies of the IgD class.

Antibodies to E. coli of the IgM, IgG and IgA class are readily demonstrable in normal human serum. Using the sensitive red cell-linked antigen-antiglobulin system, it has been demonstrated that antibodies of the IgD class are also part of this normal response. The IgD antibody titre is low and often could only be demonstrated in partially purified IgD preparations. The availability of purified IgD paraproteins and their Fabdelta and Fcdelta fragments, as well as antisera specific for these fragments, allowed the necessary critical specificity controls to be performed.


Herpes gestationis: studies on the binding characteristics, activity and pathogenetic significance of the complement-fixing factor.

The sera of seven out of eight patients with Herpes gestationis contained a factor which fixed C3 but not detectable amounts of immunoglobulin (Ig) on the basement membrane zone (BMZ) of normal human skin. Using C2-deficient human serum and C4-deficient guinea-pig serum, fixation was shown to be dependent upon activation of the classical pathway, and chromatography and immunoabsorption studies indicated the H. gestationis factor to be an IgG immunoglobulin. In all seven sera the H. gestationis factor bound to, and could be eluted from, the eluate of staphylococcal protein A. Although the H. gestationis factor failed to block staining of human sera by a FITC-conjugated antibody prepared from bullous pemphigoid (BP) serum, complement fixation by five out of seven sera of patients with H. gestationis was blocked using F(ab')2 of IgG prepared from pooled BP serum. In a single patient rapid resolution of lesions followed plasma exchange on two separate occasions, indicating the pathogenetic importance of humoral factors in this disease.


Transplantation, immunosuppression and plasmapheresis in Goodpasture's syndrome.

Renal transplantation in the face of circulating anti-glomerular basement membrane (GBM) antibody can lead to recurrent glomerulonephritis. The severity of the recurrence may be related to the level of antibody present at the time of transplantation. We describe a patient with Goodpasture's Syndrome and moderate circulating anti-GBM antibody activity who received a renal transplant, followed by plasmapheresis and immunosuppression. The graft has functioned well for almost two years associated with a continued reduction in levels of circulating anti-GBM antibody.


Observations on the evolution of idiopathic rapidly progressive glomerulonephritis.

Distinctive deposits of C3, C5 and properdin were identified in the minimally proliferative glomerular lesions of a patient with idiopathic rapidly progressive glomerulonephritis. Biopsies of her renal allograft at times of recurrences of her disease and of five other patients with progressive renal failure but less severe crescent formation showed deposits identical composition and position, giving evidence of a common pathogenesis. The deposits were subepithelial and located in that part of the basement membrane in apposition to the mesangium (capillary waist). Breaks in the basement membrane were often exclusively in this area suggesting the deposits were causative. Ancillary observations suggest that the subepithelial deposits become unidentifiable after the scarring of severe extracapillary proliferation develops. Three of the patients had, in addition, intramembranous dense deposits but in other ways their disease was not characteristic of membranoproliferative glomerulonephritis Type II. Instead, the evidence indicated that all six patients were in early or lage stages of idiopathic (non-streptococcal) rapidly progressive glomerulonephritis.


Gas chromatographic measurement of plasma levels of sodium valproate: tentative therapeutic range of a new anticonvulsant in the treatment of refractory epileptics.

1. A precise and rapid gas chromatographic method for the measurement of plasma sodium valproate concentrations is presented. 2. The extraction is a single step procedure, and is reproducible and linear throughout the concentration range encountered. 3. Clinical evaluation of the drug is presented in eighteen epileptics on the basis of the percentage of days on which subjects had seizures before and after sodium valproate therapy. 4. A tentative therapeutic range for sodium valproate is presented on the basis of plasma levels and therapeutic effect.


Total hip arthroplasty in the cardiac transplant patient.

Osteonecrosis of the femoral head following cardiac transplantation has led to bilateral total hip arthroplasties in 2 patients. The clinical course and rejections of these patients are outlined. The pathological changes in the femoral heads suggested that the process leading to osteonecrosis in the cardiac transplant patient is the same as that following renal transplantation, both being due to immunosuppression probably related to steroid dosage. Successful joint replacement can be carried out in the cardiac transplant with careful monitoring of anesthesia. Both patients have done well, being followed for 14 and 6 months respectively.


The treatment of osteonecrosis of the hip with fresh osteochondral allografts and with the muscle pedicle graft technique.

Osteonecrosis of the hip in Stages 1 and 2 are treated by conservative measures such as rest, aspirin, and a cane. If activities of daily living are impaired or stronger analgesics become necessary the muscle pedicle graft is advised. Fresh osteochondral grafts are utilized to resurface the head of the femur in Stages 3 and 4 in vigorous patients below the age of 60 when strong analgesics are required to relieve pain. A total hip arthroplasty is the treatment of choice for all patients in Stage 5 or those beyond the age of 60 in Stages 3 and 4. Five patients have had allografts; all are doing well. Three have been followed over 2 years, one over one and one-half years, and the other over 6 months. Twenty-three patients have had muscle pedicle grafts. The results have been good in the 8 patients in Stages 1 and 2. Only 5 of the 15 patients with osteonecrosis in Stages 3 and 4 have had good results.


Onlay fibular bone grafting in treatment of tibial fracture non-union.

Twenty-nine patients with tibial non-union or delayed union were treated by onlay grafting, using long struts from the ipsilateral fibula and without disturbing the non-union site. Internal fixation and excessive dissection can be avoided. Follow-up in 28 patients showed solid healing in all; 20/28 patients united the fracture within 7 months. Removal of the fibula as a distracting force, combined with the principles of onlay grafting advocated by Phemister, is effective surgical treatment.


Clinical pharmacokinetics of diazepam.

Diazepam is still one of the most used of the benzodiazepine group of drugs. Extensive studies over 10 years have defined a fairly complete profile of its kinetics. Minor aspects relating to patterns of its metabolism and excretion in certain age groups and in some disease states remain to be described quantitatively. However, there is more than sufficient kinetic information available for the requirements of good clinical practice. For optimum clinical benefit with minimum side-effects the following kinetic properties should be borne in mind: (a) there is a large interindividual variation (up to 30-fold) in dose/blood level ratios, especially when treatment is short-term; (b) the elimination half-life is prolonged in the elderly and the newborn and in some cases of liver disease; (c) there is accumulation of the active N-desmethylated metabolite during long-term treatment; and (d) administration of diazepam to pregnant women leads to rapid distribution from the maternal to fetal compartment: accumulation of both diazepam and desmethyldiazepam could cause prolonged sedation in the newborn. As there does not appear to be any clear relationship between the concentration of diazepam in the plasma and clinical effect, measurement of blood levels, other than for research purposes, is unnecessary. Based on kinetic data, a single administration of diazepam at night should be adequate for hypnotic and anxiolytic effects in most patients.


Clinical pharmacokinetics of rifampicin.

After oral administration on an empty stomach, the absorption of rifampicin (rifampin) is rapid and practically complete. With a single 600mg dose, peak serum concentration of the order of 10microgram/ml generally occur 2 hours after administration. The half-life of rifampicin for this dose level is of the order of 2.5 hours. The amount of rifampicin extracted by the liver during its first passage through the hepatoportal system and transferred to bile is relevance for the time course of distribution of the antibiotic in the blood compartment. With dose of the order of 300 to 450mg, the excretory capacity of the liver for the antibiotic is saturated. As a consequence, increasing the dose of antibiotic results in a more than proportional increase in serum concentrations. On repeated administration, and most likely as a consequence of self-induced (autoinduction) metabolism, the rate of disappearance of rifampicin from the blood compartment increases in the early phase of treatment, the phenomenon affecting mainly the levels following the peak, with a consequent reduction in half-life. Approximately 80% of rifampicin is transported in blood bound to plasma proteins, mainly albumin. Rifampicin is well distributed, although to a different degree, in the various tissues of the human body. Probably in the hepatocyte, rifampicin undergoes a process of desacetylation. The metabolic derivative, desacetylrifampicin, is more polar than the parent compound, and microbiologically active. This metabolite accounts for the majority of the antibacterial activity in the bile Rifampicin is almost equally excreted in the bile and urine, the recovery in the 2 fluids being of the same order of magnitude. Administration of rifampicin to newborn infants and children is followed by blood levels generally lower than those found in adults for the same dose levels. In patients with impaired liver and kidney function the elimination of the antibiotic from the blood compartment is slower than in normal subjects. Rifampicin has been found to compete with bilirubin and other cholefil substances for biliary excretion, giving rise to transient and reversible increased bilirubin and BSP retention values. A kinetic model study on the transfer constants between various body compartments has indicated that rifampicin is rapidly absorbed from the intestine and that the absorption rate increases with time. Rifampicin as such is transferred into urine at a rate 3 times higher than the rate of transfer into bile. Desacetylrifampicin, the more polar metabolic derivative of rifampicin, behaves in the opposite way since its rate of transfer into bile is 4 times higher than that into urine. The rate of biotransformation of rifampicin into desacetylrifampicin is of the same order of magnitude as than of biotransformation of the latter into a further metabolic derivative, which could be a glucuronide conjugate...


Effect of aspirin on exercise-induced angina.

Suspecting that platelet thromboemboli could play a role in the pathogenesis of myocardial ischemia, we did a random-order, double-blind, crossover study of the effect of the platelet aggregation inhibitor, aspirin, on treadmill exercise-induced angina in 13 men with coronary artery disease. Although collagen-induced platelet aggregation and the second phase of adenosine diphosphate (ADP)-induced platelet aggregation were significantly decreased and the rate of disaggregation of ADP-induced platelet aggregates was significantly increased after 650 mg aspirin in buffered solution, there was no delay in onset of exercise-induced angina, change in heart rate-blood pressure product at onset of angina, or change in S-T segment depression at onset of angina. Regardless of whether the patients had received placebo or aspirin on the preceding day, treadmill exercise until angina was followed by no changes in platelet aggregation or disaggregation, platelet count in blood or platelet-rich plasma, or of the plasma concentration of nonesterified fatty acids.


Clinical pharmacokinetics of carbamazepine.

Carbamazepine seems to as effect as phenytoin in the treatment of grand mal and psychomotor epilepsy. It is the drug of first choice in trigeminal neuralgia. After single oral doses of carbamazepine, the absorption is fairly complete and the elimination half-life is about 35 hours (range 18 to 65 hours). During multiple dosing, the half-life is decreased to 10-20 hours, probably due to autoinduction of the oxidative metabolism of the drug. Phenytoin and barbiturates also induce the metabolism of carbamazepine. After single doses of carbamazepine, elimination follows dose-dependent first order kinetics. Carbamazepine is metabolised by oxidation before excretion in the urine. In experimental animals, the metabolite carbamazepine-10,11-epoxide has anticonvulsant activity comparable with that of the parent drug. The plasma concentration of the metabolite during long-term treatment of epileptic patients varies between 5 and 81% of that of the parent drug. The plasma protein binding of the metabolite is about 50% compared with about 75% for the parent drug. Less than 50% of a given carbamazepine doses has been identified as metabolites in the urine. The quantitatively most important metabolites is the trans-10,11-dihydro-10,11-diol. The kinetics of carbamazepine have been explored to some extent in pregnant women, newborns and children. Plasma levels of carbamazepine seem to decrease during pregnancy, possibly as a result of increased metabolism. The drug readily crosses the placenta and the levels measured in newborns are comparable with maternal plasma concentrations. In newborns exposed to the drug during fetal life, the plasma half-lives were relatively short (8.2 to 28.1 hours) indicating an induction of carbamazepine metabolism during gestation. The pharmacokinetics of carbamazepine in children aged 0.3 to 15 years are comparable with that in adults. A single daily dose of carbamazepine is insufficient; 2 doses per day are appropriate in most cases, but some patients may benefit from more frequent dosing to avoid side-effects. Compared with phenytoin, for example, very few controlled studies have been performed to establish the plasma level range of carbamazepine associated with the best therapeutic outcome. However, the best anticonvulsant effect of carbamazepine seems to be obtained at plasma levels of about 5 to 10microgram/ml (20 to 40mumol/L). Side-effects are most frequent at higher levels but may also be seen at lower levels.


Trimethoprim/sulfamethoxazole and renal function in transplant patients.

Twenty-two patients with functioning renal allografts took part in a double-blind crossover trial during which placebo, sulfamethoxazole, and trimethoprim/sulfamethoxazole were given for periods of 14 days. The patients were divided into 2 groups. The first group consisting of 12 patients had serum creatinine levels less than 0.18 mmol/L and the second group of 10 patients had serum creatinine levels between 0.18 mmol/L and 0.35 mmol/L. Renal function at the end of each period was assessed by clearance of inulin (CIn), p-aminohippurate (CPAH) and endogenous creatinine (CCr). The second group also had a pitressin concentration test as a measure of distal tubule function. There was no change in inulin or creatinine clearance or in maximum concentration after pitressin in any of the patients in any of the phases. In the first group there was an increase in PAH clearance during the sulfonamide and trimethroprim/sulfamethoxazole phases. This change was not seen in the second group of patients with significantly impaired renal function.


Rhytidectomy.

The success of rhytidectomy depends on the selection of the patient, the technique and skill of the surgeon, and preparation of the patient prior to surgery. The patient must be made aware of what to expect before, during, and after the operation. Patients can expect to look presentable enough to appear in public in 2 to 3 weeks following the surgery. The final result will be apparent in from 6 to 8 weeks after surgery (Figs. 8-10).


Clinical pharmacokinetics of procainamide.

Procainamide is almost completely absorbed after oral administration and peak plasma concentrations are generally reached within 1 to 2 hours. Upon intravenous administration there is a rapid initial distribution phase, which is completed after about 30 minutes. The pharmacokinetics can be described by a 2-compartment open model. The plasma half-life during the beta-phase averages 3 hours. The apparent volume of distribution is about 2L/kg body weight. At therapeutic plasma levels about 15% is bound to plasma proteins. Approximately 50% of administered procainamide is eliminated as unchanged drug via the kidneys. N-Acetylprocainamide is the main metabolite and is the main metabolite and is pharmacologically active, with a recovery in urine of about 15% (range 7 to 34% in healthy subjects). The acetylation of procainamide seems to be under the same monogenic control as that of isoniazid. At least 2 more metabolites have been found but are not yet identified. The renal clearance of procainamide ranges from 179 to 660ml/min. Glomerular filtration and active tubular secretion seem to be the most important mechanisms. In patients with low-output cardiac and/or renal impairment, the absorption, distribution and elimination of the drug may be significantly altered. Determination of plasma levels is of particular value in these cases and will contribute to more safe and effective therapy in the majority of patients. As N-acetylprocainamide seems to have pharmacological effects comparable with those of procainamide, both agents should be monitored simultaneously in order to optimise therapy.


Clinical data evaluation and the PL health control information system.

In a health control service environment, that is, a periodic, membership AMHTS type of comprehensive health check-up system, where clinical data evaluation especially an evaluation in terms of subject-specific normal ranges, is most important, the medical information system is required to handle: (1) Various network types files; (2) real-time immediacy; (3) an asserted reliability to meet personal health control purposes. As in other computer applications already successfully used, an indexed direct assess method (IDAM) developed is our solution. It allows us to provide multiple indices for the file network, instead of inverted files, a unique index-to-record relationship, preventing any unrecoverable chaining destruction and, thereby, provides any network type access a stable access time. Furthermore, for research purposes, a data integrity for on-line access and batch access was attained as well as a retrieval language system with a multiple key retrieval function.


Automated classification of MMPI profiles into psychotic, neurotic or personality disorder types.

A Fortran program has been developed which can objectively classify Minnesota Multiphasic Inventory (MMPI) profiles as being psychotic, neurotic, personality disorder, or indeterminate types. The method used is a set of configural rules, 'Henrichs' rules for males'. The only input data required are K-corrected T scores, which are the end product of standard scoring techniques. To automate these rules it was necessary to rewrite them so that all decisions were the result of arithmetic comparisons or logical tests using only and, or and not. In particular, examination of the Welsh code, which many rules required, had to be stimulated by the use of several sorted arrays. The program has been carefully tested and is in the use in our computer lab.


Chinese alchemy: confluence and transformation.

The study of China's alchemical tradition can provide considerable insight into early Chinese medical theory, pharmaco-therapeutic practice and psychosomatic concepts. Chinese alchemy is a complex blending of philosophical, cosmological, physiological and natural scientific thought. This article presents a historical survey and analysis of some important aspects of Chinese alchemical research and theory.


Feline salmonellosis. A nosocomial outbreak and experimental studies.

An outbreak of S. typhimurium gastroenteritis and septicemia is described in young cats admitted to a veterinary hospital for routine medical and surgical reasons. A morbidity of 32% and a mortality of 61% was observed in the outbreak. Affected cats exhibited oral shedding of the organism and contaminated feed and water dishes may have been the vehicle of spread of infection. Possible detrimental effects of incorrect choice of antibiotic therapy are discussed. Attempts to reproduce the disease in a group of laboratory cats were unsuccessful. Antibody production was poorly correlated with infection in these cats.


DNA breakage, repair, and lethality accompanying 125I decay in microorganisms.

Effects of 125I decay in DNA were investigated by measurements of strand breaks and lethal efficiencies of the decays. In bacteriophages T1 and T4, local decay effects were compared with effects of the emitted electrons by induction of both single (ssb) and double strand breaks (dsb) in the intact phage head and in extended free state DNA. Most dsbs were found to result from local decay effects whereas most real ssbs are caused by the electrons. A simple one-to-one relationship seems to exist in the phages between the decays of 125I, numbers of dsbs and lethal effects. In E. coli rec+ and recA repair of dsbs was studied in addition to lethal decay efficiencies. In rec+ more than 70% of the dsbs were repaired within 1 h at 37 degrees C. No repair was observed in recA. The probability of lethality per 125I decay per completed genome was found to be 0.37 for rec+ and 0.93 for recA cells. The number of lethal events per unrepaired dsb was found to be practically equal to unity. Unrepaired dsbs thus seem to be the primary mechanism of lethality caused by 125I decay, and all unrepaired dsbs seem to be lethal.


Double-blind comparison of halcinonide solution and placebo control in treatment of psoriasis of the scalp.

Twenty-seven patients with psoriasis of the scalp participated in a double-blind, paired comparison study between halcinonide solution (0.1%) and placebo. The therapeutic response was excellent in sixteen patients treated with halcinonide and in one patient treated with placebo. In the comparative evaluation halcinonide was superior in twenty-two patients, the placebo was superior in four patients, and both drugs were equally effective in one patient. There were no adverse reactions due to halcinonide, but one patient experienced pruritus with the placebo solution.


Elevation of pulmonary artery pressure as a sign of pulmonary barotrauma (pneumothorax).

Pneumothorax occurs in approximately 25% of patients maintained on high levels of positive end-expiratory pressure. In several cases at our Institution, a sudden and rapid elevation in pulmonary artery pressure (PAP) monitored by use of the Swan-Ganz catheter accompanied the development of a pneumothorax. In the three cases described, the change in PAP was observed before a pneumothorax became otherwise clinically evident. Two of the three patients had marked restrictive lung disease associated with the adult respiratory distress syndrome and the third patient had large bilateral pleural effusions. It is postulated that the rise in PAP was related to a sudden decrease in the size of an already compromised pulmonary arterial vascular bed produced by hypoxic vasoconstriction and mechanical compression secondary to the pneumothorax. In the ICU, elevation of PAP may be a useful and early indicator of pulmonary barotrauma.


[Suture of flexor tendons and substitution of flexor tendons in the "no-man's land" in children].

From 1969 to 1976, there were 14 primary, 10 secondary one-stage, and 14 secondary two-stage repairs of injured flexor tendons in the so-called 'no-man's-land'. Functional results of these three operational methods are compared in this paper and show that, in children, flexor tendons in uncomplicated wounds can be sutured primarily, even in the 'no-man's-land'. Flexor tendons in complicated wounds also may be primarily sutured, but not as effectively. In the latter case, according to the results under review, secondary two-stage repair, not secondary one-stage repair, must be applied.


Antibodies in human serum and milk induced by enterobacteria and food proteins.

Ingestion of Escherichia coli O83 bacteria by adults resulted in a transient irregular colonization leading to a serum antibody response in only four out of 14 cases examined. In all of three pregnant women, however, IgA antibodies against E. coli O83 antigen were released from colostral cells after similar bacterial ingestion although no serum antibody response was noted. The findings indicate a link between the antigenic exposure to the gut and secretory antibodies of the IgA class, presumably locally formed in the mammary gland. Antibodies of the secretory IgA class registered in colostrum may, at least partly, reflect the antigenic exposure of the gut. These antibodies are probably important in protecting against E. coli infections in the neonate, as suggested by the findings of antibodies in human milk against O and K antigens of non-enteropathogenic as well as enteropathogenic serotypes of E. coli. Furthermore, in milk of women from low socio-economic groups in Pakistan, neutralizing antibodies were present against enterotoxins of E. coli bacteria and occasionally against Vibrio cholerae enterotoxins. In addition, secretory IgA antibodies against food proteins were detected in human milk. This suggests that intestinal exposure to such antigens could stimulate a local immune response in the gut resulting in triggered lymphoid cells homing to the mammary gland. These human milk secretory IgA antibodies against bovine milk proteins may help to prevent cow's milk allergy in infants on mixed feeding, since these infants tend to have a lower serum antibody response to cow's milk proteins than infants fed mostly artificially. Furthermore, children suffering from cow's milk protein intolerance and gluten enteropathy may have higher serum levels of antibody to cow's milk protein antigens than normal children, possibly reflecting increased permeability of the intestinal mucosa for various antigens.


Immunological responses to bacterial plaque in the mouth.

A heavy load of bacteria, referred to as dental plaque, accumulates at the junction between the teeth and gum. Bacterial plaque may be considered to have three functional components: (a) cariogenic organisms, (b) organisms inducing gingival inflammation and periodontal disease, and (c) adjuvant and tolerizing agents, such as lipopolysaccharides, dextrans and levans. Sequential investigation of plaque accumulation in man has shown a correlation between gingival inflammation and both lymphocyte transformation and macrophage migration inhibition. An adjuvant effect of in vivo plaque accumulation was manifested by the enhancement of T lymphocytes in the mixed leucocyte culture reaction and of B lymphocytes, as shown by the increased response to lipopolysaccharide. It may be significant that a substantial component of bacterial plaque consists of dextrans and levans, produced by certain streptococci and actinomyces, and lipopolysaccharides from Gram-negative bacteria. These bacterial products are B cell mitogens which may have an adjuvant or tolerizing effect on immune responses. The relationships between immunogenicity, mitogenicity, adjuvanticity and tolerogenicity of lipopolysaccharides, levan and dextran have not been clearly defined. However, important variables of the polyglycans are the molecular weight, type of branching, negative charge, epitope density, degradability, dosage and the sequence between mitogen and antigen. Dental plaque in man is a focus of B cell mitogens and T cell antigens which may modulate the immune responses in such a way as to induce a protective response in the development of caries and a damaging response in periodontal disease.


Sites of synthesis and localization of IgE in rats infested with Nippostrongylus brasiliensis.

The tissue and cellular localization of IgE has been studied in normal rats and rats infested with the enteric parasite, Nippostrongylus brasiliensis. The results of the study do not support the suggestion that IgE is a secretory immunoglobulin with a physiology analogous to that of IgA. The lamina propria of the small intestine and the colonic and pulmonary mucosal surfaces contain numerous anti-IgE-binding cells, but these have been shown to be mast cells and not plasma cells. The major sites of IgE synthesis were the regional lymph nodes of the small intestine and the lungs, which contained large numbers of IgE-secreting plasma cells. Smaller numbers of IgE-secreting plasma cells were also found in peripheral lymph nodes, some of which were distant from tissues known to have direct contact with either larvae or adult worms. Peyer's patches, the intrapulmonary lymphoid tissue and the spleen contained few, if any, IgE-secreting plasma cells. The significance of the IgE which was readily demonstrated in germinal centres of Peyer's patches and several lymph nodes is not known. In contrast to infested animals, the lymphoid organs of normal rats rarely contained any IgE-containing cells. Thoracic duct lymph from infested animals contained only few IgE-containing large lymphocytes, similar in number to cells containing IgM or IgG but only 1/50 as many as those containing IgA. An unexpected observation was that mast cells in mucosal organs appear to contain intracellular IgE, differing in this respect from connective tissue mast cells. Mast cells lying between epithelial cells, the 'globule leucocytes', also appear to contain intracellular IgE and it is suggested that such cells may be responsible for the presence of IgE in exocrine secretions. This study highlights the need for careful identification of cells appearing to contain IgE and suggests reasons for the widely differing reports of the numbers of IgE-secreting plasma cells in human intestinal biopsies.


Immunology of the gut: role of the eosinophil.

The gut wall is one of the conspicuous sites of eosinophil accumulation, presumably because of local chemotactic stimuli. It is reasonable to assume that one chemotactic factor is released by the mast cell, which is often found in proximity to the eosinophil. The association of eosinophils and eosinophilia with allergic disorders has long been recognized, and recent work has shown that increased eosinophil production is mediated by the lymphocyte. That process shares characteristics with other immunological actions. An increased rate of eosinophil tissue accumulation and destruction may be the factor which initiates the mechanism for increased production. None of many hypotheses about the 'function' of the eosinophil is substantiated; nevertheless it seems likely that this member of the immunological apparatus, which tends to be distributed in the front line (mucosal and cutaneous tissues), fulfils some normal protective or homeostatic function. Aside from that assumed normal function, there is growing clinical evidence that eosinophils can at times cause host injury, for example in such states as eosinophilic gastroenteritis and endomyocarditis.


Genetic and nutritional variations in antigen handling and disease.

Low function (deficiency), within the 'normal range', of each of five immunity functions is associated with immunopathological disease, and/or defective antigen handling. These are probably genetically determined, either polygenic or single gene, but environmental factors such as diet influence them greatly, and the vulnerability may be especially great in the newborn period. The relevant systems are those involved in the immune elimination of antigen (antibody and macrophages) and those possibly involved in the immune exclusion of antigen (IgA, the alternative pathway of complement, and cilial action). The gut has an especially complicated role in antigen-handling, and feeding influences its capacity to do so. Eczema was prevented by a regimen of neonatal antigen avoidance, which was largely breast-feeding, and it is likely that other immunopathological diseases result from antigen contact during periods of malnutrition. The mechanisms of such effects are likely to be complicated, but adjustment of the environment to suit the genetically vulnerable, particularly in the newborn period, can lead to the prevention of disease.


Gastrointestinal complications of immunodeficiency syndromes.

Patients with B cell deficiency have a high incidence of prolonged Giardia lamblia infection of the gastrointestinal tract that causes symptoms of malabsorption with villus flattening. The changes are reversible with therapy directed against Giardia. There is a high incidence of pernicious anaemia in patients with agammaglobulinaemia. Those with abnormal B lymphocytes tend to develop lymphoid nodular hyperplasia. Gastrointestinal disease is rare in boys with X-linked agammaglobulinaemia when compared with adults with the 'acquired' or common variable form of the disease. T cell deficiency results in intractable diarrhoea and monilial infection of the gastrointestinal tract.


[Computer-assisted diagnosis of haematological disease in hospital patients (author's transl)].

A system of computer-assisted diagnosis is described which, in analogy to conventional diagnosis, takes into account both logical and statistical factors. The arrangement of such a system makes it clear that, after a period of successful use in specialist branches of medicine, a phase of less spectacular success has occurred which, however, provides the conditions for including larger areas of medicine in computer-assisted diagnosis. These systems are likely to conform more closely to the needs of the doctor than previous ones. Whether they can be used in non-hospital practice would depend largely on whether the questions put to the system by the doctor do not take more time and answers can be given in short, easily understandable form. The best type of answer as well as the transmission of information can be discovered empirically. The differential diagnostic level of computer-assisted diagnosis is, according to present experience, quite satisfactory but can be further improved. This development is greatly helped by continuing increases in the speed of calculators and their data storage capacity.


Immunopathology of coeliac disease.

Coeliac disease may be defined as a condition in which there is an abnormal jejunal mucosa with loss of villi, which improves morphologically after treatment with a gluten-free diet. Pathologically, there is damage to the jejunal enterocytes, with hyperplasia of crypt cells so that overall enteropoiesis is increased. On conventional or scanning electron microscopy the enterocytes are markedly abnormal. Histochemically, the normal punctate appearance of the lysosomes is lost and sensitive lysosomal enzyme assays on mucosal biopsy samples using isopycnic centrifugation techniques show that there is an increase in total lysosomal activity with reduction in lysosomal latency. Studies following gluten feeding in patients whose mucosa has returned to normal after treatment with a gluten-free diet show that pathological abnormalities appear within 4--8 hours of gluten challenge. Complement together with extracellular IgM can be demonstrated in the lamina propria, suggesting the formation of immune complexes. In untreated coeliac disease there is a significant reduction in serum levels of C3 and C4. There is also evidence indicating the presence of immune complexes in the serum. Coeliac disease may therefore be an intestinal model of an immune complex disease, in which an antigen derived from gluten reacts with an antibody formed locally in the gut, fixing complement and causing damage to the enterocyte by activation of lysosomes.


Immunological studies in inflammatory bowel disease.

Three aspects of immunological function were studied in patients with Crohn's disease and ulcerative colitis (inflammatory bowel disease): atopic status and serum IgE levels; serum concentration of C-reactive protein; and C3 activation. The incidence of atopy, assessed by prick testing with common allergens, did not differ in patients with inflammatory bowel disease from healthy controls. 12 of 39 patients with Crohn's disease and 5 of 20 with ulcerative colitis, among whom were some non-atopic subjects, had elevated serum levels of IgE. Serum levels of C-reactive protein in patients were significantly greater than normal, even in those in whom the disease was clinically quiescent. Symptomatic patients with Crohn's disease had significantly higher levels than similar patients with ulcerative colitis and in Crohn's disease the levels correlated well with an overall assessment of severity and disease activity. Although conversion of C3 was detected in fresh serum samples from inflammatory bowel disease patients and not controls, only minimal traces were present in just 7 of 89 samples of EDTA--plasma from 47 patients; this finding did not correlate with disease activity. However, there were low titres of immunoconglutinin in the sera of some patients, but not in controls, suggesting that complement activation may be occurring in vivo.


The secretory IgA system of the gut.

Most commonly, humoral immunity manifested in the gastrointestinal tract of mammals is due to the presence of secretory IgA antibodies. Antibody specificities have been detected in the secretory IgA of gut secretions to a wide range of naturally occurring viral and bacterial components and to test antigens such as chemically modified proteins. Much of the IgA found in gut secretions is synthesized and secreted locally by the abundant plasma cells of the lamina propria. Development of methods for establishing local protective immunity in the gut requires knowledge of the origins of these plasma cells and of the whereabouts of their precursors when they are susceptible to antigen-driven proliferation and/or maturation. The Peyer's patches have been shown to contain a population of B lymphocytes especially rich in precursors for IgA plasma cells and in cells which can repopulate gut lamina propria with such IgA plasma cells. The Peyer's patches also appear to 'sample' gut antigens, in that small amounts of antigens are passed intact through their dome epithelial cells. Recent experiments bearing on the origins, differentiation and maturation, antigen sensitivity, migration and lodging of precursors for gut IgA plasma cells are discussed. We use the following three systems: (1) congenic transfer of cells from different murine lymphoid cell sources or mixtures of these (CB20 leads to BALB/c or BALB/c leads to CB20) and the use of allo-antisera to IgA allotypic determinants to assess their potential to impart an adoptive IgA antibody response to the recipient and to repopulate its histocompatible lamina propria with IgA plasma cells; (2) clonal precursor analysis (the method of Klinman) both to enumerate antigen-sensitive cells in different tissues of mice and to evaluate their potential to generate plasma cells making particular isotypes and idiotypes of antibodies; (3) use of pairs of Thiry-Vella loops in rabbits, each member either bearing or lacking a Peyer's patch, and quantitation of antibodies of each isotype and of total secretory IgA to assess the response of each loop with the time after local immunization. The results from all three systems provide strong evidence for the importance of Peyer's patches in supplying cells responsible for local humoral immunity and suggest both a differentiative pathway for IgA precursors and their whereabouts when antigen may cause the expansion of a population of specific cells.


The natural history of the cells producing IgA in the gut.

The IgA-secreting cells in the lamina propria of the small intestine are derived from large lymphocytes which enter the blood by way of the thoracic duct and then migrate into the gut where they complete their differentiation into plasma cells. Three aspects of this cellular traffic have been examined in rats. 1. The cells in thoracic duct lymph which give rise to IgA-secreting cells in the lamina propria are among those which carry surface IgA. Blast cells lacking surface immunoglobulin migrate mainly into the Peyer's patches and do not contribute to the IgA response. 2. Studies on a secondary antibody response to cholera toxoid, in which the challenge was given into a Thiry-Vella loop, showed that the antibody-containing blast cells in thoracic duct lymph were derived from Peyer's patches. The mesenteric nodes contributed little, if anything, to the cellular response in the lymph. 3. The idea that secretory component is a signal for the emigration of large lymphocytes from the blood into the lamina propria lacks experimental support. Secretory component does not bind to the IgA on the surface of thoracic duct cells. On the other hand, antigen in the gut may play an important part in immobilizing large lymphocytes in the lamina propria once they have migrated.


Significance of immune mechanisms in relation to enteric infections of the gastrointestinal tract in animals.

The impact of bacterial colonization on the alimentary tract in early life is reflected in gross changes in morphology. Subsequent health, if not survival, may largely be determined by a continuum of local intestinal immune mechanisms and it is essential for antibody development during the neonatal period to compensate adequately for declining passive maternal antibody. Consequent upon the development of the gut microflora the lamina becomes infiltrated with immunocytes in which the dominant immunoglobulins produced are IgM and IgA. Both immunoglobulins are transported across the epithelium by a process involving membrane-bound vesicles. Germ-free and fistulated pigs and calves are shown to be able to respond to oral immunization with Escherichia coli O somatic antigens during the first week of life. Resistance to infection with enteropathogenic E. coli was significantly enhanced, along with other parameters of nutrition and performance. However, in the young chick, although the intestinal response to infection with E. coli was similar to that in the mammal, no response to E. coli O antigens could be determined on oral administration in germ-free or local intestinal applications in fistulated birds. In the mammalian intestine secretory antibodies participate in the control of pathogenic E. coli by blocking adhesion to the mucosal epithelium, interfering with the elaboration of surface antigens, inhibiting toxins, and facilitating rapid elimination from the alimentary tract by agglutination and bacteriostasis. In consequence fewer enteropathogens are excreted into the environment, an important feature in modern intensive systems of animal production.


[Immunofluorescence test in the diagnosis of mushroom worker's lung (author's transl)].

Growing and harvesting a new edible mushroom (Pleurotus florida mushroom--oyster mushroom) liberates a high amount of spores the inhalation of which causes symptoms similar to those of "farmer's lung". The Ouchterlony test detects precipitins against antigens of the spore membrane only in cases with high serum antibody levels, i.e. only one in eight sufferers from the disease had a positive antibody test. Because of this, indirect immunofluorescence was used as a more sensitive method for serum antibody detection: all mushroom workers with clinical symptoms were found to have precipitating antibodies. The test is, therefore, superior to the Ouchterlony one, is simpler and saves time. Furthermore, the immunoglobulin class can easily be obtained at the same time.


[New vistas on rubidium].

Rubidium salts have been used in human therapy since the end of the last century. The fact that an actual use in psychiatry has been considered is mainly due to Meltzer and al's works in 1969. The pharmacological studies do not reveal any psychopharmacological "provile" presently known; they point out that Rubidium has stimulant properties, whick, in certain conditions, can increase activity, central excitability and sometimes aggressiveness, among the animals used for the experiments. The hypothesis of a contingent antidepressant action of Rubidium is essentially based on the existence of properties opposite to those of Lithium. This is especially true in the biochemical field: Rubidium may enhance the release of Norepinephrine whereas Lithium has an opposite effect. The toxicological studies show that, because of some properties common to Rubidium and Potassium, it is necessary to control Potassium intake and to avoid that Rubidium replace too high a percentage of this ion: the extended half-life (about forty days in man) makes necessary the working up of chronical studies to evaluate the toxicity which is linked to its long-term accumulation. For Rubidium blood concentrations superior to 1 mEq/1., the first clinical studies seem to point out that an antidepressant action would exist. Nevertheless a certain delay of action is necessary to the onset of a therapeutic effect; no noticeable adverse effect has been detected.


Luteinizing hormone-releasing hormone in prepubertal and pubertal girls.

Estimations of immunoreactive LH-RH and LH in pooled sera of girls, adult women and postmenopausal women have been carried out. The girls were divided into three groups: I--girls aged 2--4 years, II--girls aged 5--8 years and III--girls 9--12 years of age. The estimated concentrations of LH-RH in particular groups were as following: in group I--1.2 +/- 0.2 pg/ml, in group II--2.2 +/- 0.4 pg/ml, in group III 31.0 +/- 4.4 pg/ml, in adult women 6.3 +/- 1.8 pg/ml. and in postmenopausal women 16.6 +/- 2.4 pg/ml. The concentrations of LH in the same groups were 4.3 +/- 0.7; 4.5 +/- 0.8; 11.0 +/- 1.4, 23.3 +/- 2.4; and 120.0 +/- 14.7 mIU/ml, respectively. The authors suggest that the sexual maturation of girls is initiated by the enhanced hypothalamic activity, reflected in higher concentrations of immunoreactive LH-RH in peripheral serum.


Verapamil: a review of its pharmacological properties and therapeutic use.

Verapamil is a novel antiarrhythmic and antianginal agent which, although introduced in 1962, has only recently gained prominence not only as a significant agent in cardiovascular therapeutics but also as a powerful tool to examine the nature of some of the biophysical phenomena at the membrane of cardiac and other excitable tissues. Verapamil is the prototype of those agents which selectively inhibit membrane transport of calcium, an action which accounts for the drug's peripheral and coronary vasodilator properties, its effect on excitation-contraction coupling and hence its negative inotropic propensity, as well as its depressant effects on the sinus node and atrioventricular conduction. Its pharmacological effects are largely independent of the autonomic nervous system. The main therapeutic uses of the drug are in the management of atrial tachyarrhythmias, angina, and possibly hypertension. The overall exp:rimental and clinical data suggest that verapamil will become an important and safe addition to existing drug regimens, especially as an agent of choice for the short-term treatment of most cases of paroxysmal supraventricular tachycardias. The initial experience in other arrhythmias, angina and hypertension, is also sufficiently encouraging to justify further detailed clinical trials to define its potential role in cardiovascular therapeutics.


Isolation and properties of two protein kinases from yeast which phosphorylate casein and some ribosomal proteins.

Three fractions of protein kinase from postribosomal supernatant of Saccharomyces cerevisiae, active in phosphorylation of casein, were resolved on DEAE-cellulose. Two of these fractions: protein kinase 1 and protein kinase 3, were further purified about 1000 and 1800-fold respectively. The kinase 1 appeared to exist as a monomer with a molecular weight of 50 000 and utilized only ATP as phosphoryl donor. The protein kinase 3 was an aggregated form of enzyme with a molecular weight of above half a million and used both ATP and GTP for protein phosphorylation. Both isolated enzymes showed variations in respect to Michaelis constants, and inhibitory effects exerted by monovalent cations and nucleotide phosphates. The activity of the kinases was not affected by the presence of cAMP (adenosine 3':5'-monophosphate) or cGMP, however, only protein kinase 1 appeared to be a cAMP nucleotide-independent enzyme. Despite these differences both enzymes equally phosphorylated two strongly acidic proteins of the 60-S ribosome subunit, possibly related to L7, L12 of Escherichia coli.


Threonyl-tRNA, lysyl-tRNA and arginyl-tRNA synthetases from Baker's yeast. Substrate specificity with regard to ATP analogues.

Sixteen analogues of ATP have been tested in the aminoacylation reaction of threonyl-tRNA, lysyl-tRNA, and arginyl-tRNA synthetases from baker's yeast. Two compounds are substrates for threonyl-tRNA and for lysyl-tRNA synthetases and five compounds for arginyl-tRNA synthetase. There are six inhibitors for threonyl-tRNA, nine for lysyl-tRNA, and six for arginyl-tRNA synthetase. Their Km and Ki values have been determined. Thus positions 2, 6, 7, 8 and 9 of the purine moiety and 2' and 3' of the sugar moiety of the ATP molecule are important for catalytic action of these aminoacyl-tRNA synthetases. Remarkably arginyl-tRNA synthetase is the first aminoacyl-tRNA synthetase which tolerates bulky substituents at the sugar moiety of ATP. These data fit with the idea that synthetases of subunit structure need magnesium-ion-ATP complexes with an anti conformation as substrates whereas single-chain enzymes accept this substrate in the syn conformation.


Changes in chromatin properties after partial extraction of non-histone proteins.

By treatment with tRNA in the presence of 1 mM MgCl2, a chromatin preparation was obtained containing all five major histone fractions but lacking a considerable portion of non-histone proteins. This chromatin preparation as well as chromatin extracted with 0.6 M NaCl (depleted of H1 histone and some non-histone proteins) were characterized in respect of solubility and chromatin DNA accessibility. Both samples possessed practically the same solubility in the presence of 0.15 M NaCl and 1 mM MgCl2. The solubility of tRNA-treated chromatin in 5 and 10 mM MgCl2 was higher than that of salt-extracted chromation. The accessibility of the DNA of these chromatin preparations was tested with DNA-dependent RNA polymerase of Escherichia coli as a probe, using procedure that permits measurement of binding site frequency. Both tRNA-treated and salt-extracted chromatin contained as many as 33% and untreated chromatin as few as 4% of the number of binding sites found on protein-free DNA. These results demonstrate that at least in part the non-histone proteins are responsible for salt-induced insolubility and low DNA accessibility of chromatin, thus revealing the importance of non-histone proteins in the maintenance of an overall chromatin structure.


The aminoacyladenylate mechanism in the aminoacylation reaction of yeast phenylalanyl-tRNA synthetase.

It is shown from a combination of rapid quenching and steady-state kinetics that the phenylalanyl-tRNA synthetase from yeast catalyses the formation of phenylalanyl-tRNA by the amino-acyladenylate pathway at pH 7.8 and 25 degrees C. The rate-determining step at saturating reagent concentrations is not the dissociation of the charged tRNA from the enzyme.


Does verapamil have a clinically significant antihypertensive effect?

Verapamil was evaluated as an antihypertensive agent in a pilot study. Intravenous administration of 0.1 mg/kg, followed by constant infusion of 0.0035 mg/kg min, reduced both systolic and diastolic blood pressure significantly; the maximal average decrease of 23/16 mm Hg occurred after 5 min. The resting pulse rate rose during infusion and prolongation of the atrio-ventricular conduction time was a constant finding. After the initial drop in blood pressure, a rise toward control levels was observed, despite an increase in the infusion rate. Five patients received oral treatment with verapamil 320-640 mg daily for 7 weeks. In four of the five patients a blood pressure reduction was obtained (mean: 14/12 mm Hg), but normotension was not achieved in any of them. In contrast to the acute studies, the atrio-ventricular conduction time showed no change and a decrease in resting pulse rate was noted. Two patients experienced sensations of heat and reddening of face during treatment. It is concluded that verapamil has a rather modest antihypertensive effect and it is not suitable for the treatment of arterial hypertension.


Erythromycin succinate in the treatment of acute exacerbations of chronic bronchitis.

In 20 patients with an acute exacerbation of chronic respiratory tract infection the effectiveness of oral erythromicin succinate 3 X 500 mg daily has been tested. The duration of treatment was 10 days in all cases. The criteria of success, in addition to the clinical findings, were the results of bacteriological investigations and assessment of the appearance of the sputum. In all patients sputum and serum concentrations or erythromicin were determined. All pathogens isolated from the sputum of the patients were erythromicin-sensitive. One instance of development of resistance was observed. The drug was well tolerated.


Influence of pindolol (Visken) on respiratory function in 20 asthmatic patients.

The effect of a single oral dose of pindolol on bronchi was studied in a double-blind cross-over trial in 20 adult patients, most of whom had moderate bronchial asthma. A single dose of pindolol 5 mg, sufficient to cause a significant fall in heart rate and blood pressure at rest, did not produce a significant fall in the forced expiratory volume (FEV1.0). However, two patients showed marked deterioration in lung function after pindolol. A conventional therapeutic dose of salbutamol by inhalation produced a significant increase in ventilatory function relative to placebo, but it did not outweigh the bronchial effect of pindolol.


Effects of retinoic acid on the immune system: stimulation of T killer cell induction.

Retinoic acid (RA), a vitamin A derivative with anti-tumor activity, was assayed for its effects on the immune system in mice. High doses of this compound (1000 microgram/mouse/day) have toxic effects and cause depletion on the peripheral lymphoid organs (spleen, thymus) while leaving the bone marrow cells unaffected. Both the in vivo and in vitro induction of cell-mediated cytotoxicity (CMC) to allogeneic tumor cells is stimulated at least tenfold by low doses (25--300 microgram/mouse/day) of RA while high doses suppress CMC induction. RA is shown to be a specific adjuvant for the induction of cytotoxic thymus-derived lymphocytes (T cells) and not a general T cell mitogen or adjuvant. It does not enhance the proliferative response in the mixed lymphocyte culture nor does it stimulate lymphocyte proliferation in response to the mitogens concanavalin A and phytohemagglutinin. The induction of cooperating T cells and the delayed-type hypersensitivity reaction are also not stimulated by RA. In contrast to the reported stimulatory effects of retinyl palmitate and retinyl acetate, RA does not stimulate the humoral response to erythrocytes. The strong adjuvant effects that RA has on the induction of CMC at low doses may be responsible for its anti-tumor activity.


An antiserum which recognizes lipopolysaccharide-reactive B cells in the mouse.

Rabbit antisera have been prepared against spleen B cells from C3H/Tif mice, high responders to lipopolysaccharide (LPS). After complete absorption on tissues of C3H/Hej mice (LPS nonresponders), such antisera specifically stain and kill (in the presence of complement) a fraction of the B cells from a number of LPS high responder strains, and fail to recognize any cells in two different LPS nonresponder strains, C3H/HeJ and C57B1/10.Sc.Cr. The ontogeny, organ and strain distribution of this B cell marker parallels LPS reactivity. Frequencies of cells stained by this antiserum correspond to the frequencies of LPS-reactive B cell precursors recently determined. This antigent(s) is expressed by LPS-activated B cell blasts but not by cells which remain small after 48 h in the presence of LPS. Removal of the cells recognized by the antisera leads to depletion of LPS-reactive cells, while enriching for reactivity to another B cell mitogen, e.g. lipoprotein.


Suppression of an in vitro humoral immune response by cultured fetal thymus cells.

We studied the function of fetal thymocytes, derived from thymus progenitor cells of 14-day-old fetuses in an organ culture system, in an in vitro humoral immune response. The unprimed cultured fetal thymocytes suppressed the T-dependent primary immune response to adult syngeneic spleen cells against sheep red blood cells, but failed to suppress the response against the T-independent antigen NIP-POL [4(hydroxy-3-iodo-5-nitrophenyl)acetyl-coupled polymerized flagellin]. The suppression was abolished by anti-Thy-1 serum and complement treatment. Using a differential killing procedure, the suppressor cells were characterized as "low" Thy-1 cells. In addition, they were resistant to hydrocortisone. Suppression could only be achieved when the cultured fetal thymocytes were added during the first 48 h of culture, suggesting that their action occurred during the induction phase of the response. The implications of the high frequency of suppressor cells during fetal life are discussed.


Experimental pyelonephritis induced by L-forms of Proteus mirabilis in rats.

Pyelonephritis was produced in 75 white rats by applying a 24-hour ligature on the ureter and by intravenous injection of a suspension of 5X10(9) cells of a stable Proteus mirabilis L-form. Pyelonephritis was proved microscopically in 44% of the animals. The revertants of the introduced L-form play an etiological role in the development of the infection. The stability of the pathohistological findings makes this model suitable for the purpose of experimental chemotherapy.


Animal experiments on the compensation of the immunosuppressive action of cyclophosphamide by 2-[-2-cyanaziridinyl-(1)-]-2-[-2-carbamoylaziridinyl-(1)]-propane BM 12 531.

BM U2 531, the 2-[2-Cyanaziridinyl-(1)-]-2-[-2-carbamoylaziridinyl-(1)-]-propane, the further development of BM 06 002 is able to compensate the immunosuppressive action of Cyclophosphamide and to increase the carcinostatic action of Cyclophosphamide. These properties are demonstrated 1. by a leucocytosis induced after application of BM 12 531 in rats 2. by a quick restauration of leucocyte depression induced by Cyclophosphamide in rats and dogs 3. by an increase of resistance against an infection (candida albicans) in mice 4. by an increase of antitumour effect of Cyclophosphamide against a DS-carcinosarcoma in rats.


Cellular changes of adrenal under the acute stress of O-chlorobenzylidene malononitrile (CS).

This investigation describes histological and cytometrical changes of cortical and medullary tissue of adrenal in rats under the acute stress of O-chlorobenzylidene malononitrile (10 mg/kg and 20 mg/kg). It has been observed that after injection of CS, the adrenal gland showed histological changes both in the cortical and medullary region.


The influence of aromatic amines and folate on acid production by Escherichia coli.

Folinic acid, adrenaline and noradrenaline, substances known to stimulate oxygen consumption by E. coli, are shown in this experiment to do so by different mechanisms. This work demonstrates stimulation of acid production by folinic acid and inhibition by adrenaline and noradrenaline.


A preliminary study on the behaviour and biochemical responses subsequent to the injection of 5,6-dihydroxytryptamine into the substantia nigra of the rat.

Injection of 5,7-dihydroxytryptamine into the substantia nigra of rats produces an increase of dopamine in the ipsilateral striatum, and when these animals are injected with amphetamine they do not exhibit any rotation. The mode of action of this neurotoxin is compared with that of 6-hydroxydopamine.


Immunofluorescent localization of the acid-stable proteinase inhibitor (antileukoprotease) of human cervical mucus.

Localization of the acid-stable proteinase inhibitor of human cervical mucus within the epithelium of the upper cervix was possible by indirect immunofluorescence.


Inhibition of neural tube closure by ionophore A23187 in chick embryos.

Ionophore A23187 inhibited closure of the chick neural tube through its effects on cytoskeletal components.


An immunofluorescent method for identification of isolated thyrotropic cells.

A sensitive and specific immunofluorescent method for identification of thyrotropic cells was developed. The TSH-producing cells were found to be heterogenic in their morphology and intensity of staining.


Polyvinylchloride (PVC) particles implantation in mouse liver. A technique for experimental study of schistosome eggs-induced liver pathology.

An injection of suspended PVC particles in the caecal vein of mice induces a foreign-body portal granuloma reaction in the liver. Plastic casts of the portal system, after PVC particles implantation, show modifications in the portal bed and are compared with plastic casts obtained in mice infested by Schistosoma mansoni. This technique can be useful to study the cellular dynamics of the portal granuloma and can be a model for schistosomal eggs induced liver pathology.


Contribution of cardiopulmonary baroreceptors to the control of the kidney.

The role of cardiopulmonary receptors in the control of renal sympathetic nerve activity and of renin release is reviewed. The evidence indicates that cardiopulmonary receptors with vagal afferents exert a tonic inhibition on both renal nerve activity and on renin release. The magnitude of this inhibition appears directly related to changes in blood volume. Atrial as well as ventricular receptors can influence the secretion of renin. Cardiopulmonary receptors with vagal afferents may also reflexly modulate renal prostaglandin secretion. There is preliminary evidence to suggest that cardiopulmonary receptors with sympathetic afferents can influence renal nerve activity. The limitations of previous studies are outlined and a direction for future studies is suggested. It is concluded that alterations in cardiopulmonary vagal afferent input and the resulting changes in renal nerve activity and in renin release are appropriate for the maintenance of blood volume homeostasis.


Value of luteinizing hormone-releasing hormone testing in bromocriptine treatment of amenorrhea and hyperprolactinemia in patients with pituitary tumors.

The results of bromocriptine treatment in 13 patients with radiologically evident pituitary tumors are described. A menorrhea was present in all patients, hyperprolactinemia in 12 of the 13 patients, and acromegaly in 3 patients. Five patients have previously been treated surgically and by radiotherapy because of suprasellar extension of the adenoma. Plasma prolactin levels after one single dose of 2.5 mg of bromocriptine were found to have no predictive value as to the dosage needed for treatment, whereas the plasma gonadotropin response after the administration of luteinizing hormone-releasing hormone appeared to be predictive with respect to the return of ovulation during bromocriptine therapy.


D-leucine-6-luteinizing hormone-releasing hormone ethylamide in the treatment of normogonadotropic oligoasthenospermia.

The effectiveness of D-leucine-6-luteinizing hormone-releasing hormone ethylamide (D-Leu-6-LH-RH-EA) in the treatment of idiopathic normogonadotropic oligoasthenospermia was assessed in 17 patients selected on the basis of at least three previous sperm counts; a history of long-standing infertility; normal serum levels of luteinizing hormone, follicle-stimulating hormone, and testosterone; and lack of any evidence of other pathologic involvement. On testicular biopsy all patients showed hypospermatogenesis or arrest at the spermatid stage with the exception of two with more severe disorders. D-Leu-6-LH-RH-EA- was administered intramuscularly for 90 days at a daily dose of 5 microgram (four patients), 10 microgram (four patients), 20 microgram (five patients), and 200 microgram (four patients). The results showed no significant improvement in the parameters considered (number of spermatozoa per milliliter, percentage of live and motile spermatozoa, and percentage of forwardly progressive spermatozoa). D-Leu-6-LH-RH-EA does not seem promising for the treatment of oligoasthenospermic patients.


Phylogeny of lymphocyte heterogeneity. I. Membrane immunoglobulins of teleost lymphocytes.

Immunofluorescence studies of bream lymphoid tissues revealed that our 90% of the lymphocytes from blood, anterior kidney, spleen and thymus exhibited membrane immunoglobulin determinants. Furthermore, a majority of such cells were observed to undergo patching and capping when the membrane proteins were complexed with antisera to fish serum immunoglobulins. Lactoperoxidase catalysed radioiodination, detergent lysis and immunoprecipitation with appropriate antisera were employed to study the properties of this membrane immunoglobulin. Quantification, by inhibition of immunoprecipitation with serum immunoglobulin, indicated the average amount of immunoglobulin determinants for bream lymphocytes from either blood, anterior kidney, spleen or thymus to be about half that present on mouse B cells. Physiochemical characterization of labeled membrane immunoglobulin from bream lymphocytes suggested that only one class of immunoglobulin heavy chain was present and that about one-half of this material resembled the monomeric (2H-2L chain) IgM-like proteins present in bream serum. A major unanswered question raised by this study was whether or not certain of the bream membrane immunoglobulin determinants were associated with molecules that did not resemble "classical" immunoglobulins.


Critical role of the thymus in establishing humoral immunity in amphibians: studies on Xenopus thymectomized in larval and adult life.

Proliferative studies on spleen lymphocytes suggest the absnece of induced cellular activity to sheep erythrocytes in Xenopus thymectomized at 7 days of age. Immunological studies (measurement of splenic rosette-forming and plaque-forming cells and serum haemolysins) show that throughout larval life the thymus plays a critical role in establishing reactivity to red cells, since thymectomy as late as 40 days (stage 57) impairs the antibody response. In contrast, thymectomy during metamorphosis or in early adult life has no apparent debilitating effect.


The effects of de-caffeinated coffee versus whole coffee on hyperactive children.

The effects of whole coffee and de-caffeinated coffee on hyperactive children were compared, using a double-blind crossover design. Reactions were assessed by tests of concentration, digit recall, visuo-motor co-ordination, and parents' and teachers' rating scales. Whole coffee was associated with a significant improvement on all measures when compared with de-caffeinated coffee. The results suggest that whole coffee as part of the normal diet may be a useful first step in the treatment of hyperactive children.


Oral cimetidine in reflux esophagitis: a double blind controlled trial.

The efficacy of cimetidine (1.6 g per day) was evaluated using a double blind placebo-controlled trial in 24 patients with moderate or severe peptic reflux esophagitis. The results show that cimetidine is superior to placebo when using endoscopic and histological criteria. Improved patient symptomatology and lower antacid comsumption failed to reach statistical significance. No change in the abnormally low lower esophageal sphincter pressure was observed at the end of the trial. No clinical side effects or significant biochemical changes were noted during the trial.


Incidence and pathophysiology of pulmonary edema in fulminant hepatic failure.

Thirty-seven of 100 consecutive patients with fulminant hepatic failure had clinical and radiological evidence of pulmonary edema. None of them had clinical evidence of left heart failure, and the pulmonary artery wedge pressure measured in 12 patients was normal. Similarly, there was no evidence to incriminate renal failure, endotoxemia, or hypoalbuminemia. However, there was a significantly higher incidence of pulmonary edema in patients with cerebral edema, suggesting either a central origin for the pulmonary edema or common factors predisposing to edema in both sites. An additional local factor may have been the presence of intrapulmonary vasodilatation. Detailed isotope studies in 11 patients showed a significantly increased pulmonary extravascular water volume in the patients with pulmonary edema which was in keeping with the severity of the radiological changes. Although the over-all mortality was higher in those patients with pulmonary edema than in those without, the difference was not significant, and early ventilation with positive and expiratory pressure achieved adequate oxygenation in all but 3 patients.


Context effects on nonsense codon suppression in Escherichia coli.

The influence of mRNA context on nonsense codon suppression has been studied by suppression measurements at one site in the Escherichia coli trpE gene and at two sites in the trpA gene. The ratio of suppression efficiencies of amber and ochre codons at each site (homotopic pairs) has been compared using ochre suppressing derivatives of tRNATyr. This ratio is independent of differential effects of the inserted amino acid on enzyme function. We have found that mRNA context can change the ratio of suppression efficiencies of homotopic nonsense codons at the three sites in the trp gene system over a ten-fold range. The causes of such variation, and, in particular the effect of certain adjacent nucleotides on nonsense codon suppression are considered.


Selection of Salmonella typhimurium mutants with altered serine transhydroxymethylase regulation.

In Salmonella typhimurium the glyA gene product, serine transhydroxymethylase (E.C. 2.1.2.1.; L-serine:tetrahydrofolate-5,10-hydroxymethyltransferase) is responsible for the interconversion of serine and glycine. This reaction also provides the cell with one-carbon units from the 5,10-methylene-tetrahydrofolate formed during glycine synthesis. Despite the importance of this enzyme, however, no mutants in which its regulation has been specificially altered have been isolated. To isolate such mutants, we have devised a selection procedure using a strain (glyA951) in which the serine transhydroxymethylase activity is reduced. When this enzyme is completely repressed, the mutant requires gylcine for growth. Revertants which retain the glyA951 lesion, but no longer require glycine, have been isolated and the serine transhydroxymethylase regulation examined. One revertant has a 7-fold elevated serine transhydroxymethylase level, which can be repressed the normal amount (about 5-fold) when the cells are grown in supplemented media. Another revertant has only a 2-fold higher serine transhydroxymethylase level; however, the amount of repression is reduced. The new lesions in both mutants cotransduce with the glyA gene and are distinct from other mutations that alter the regulation of both serine transhydroxymethylase and the methionine biosyntheitc enzymes.


Twenty-six chromosomal genes needed to maintain the killer double-stranded RNA plasmid of Saccharomyces cerevisiae.

The double-stranded RNA killer plasmid gives yeast strains carrying it both the ability to secret a protein toxin and immunity to that toxin. This report describes a new series of mutants in chromsomal genes needed for killer plasmid maintenance (mak genes). These mutants comprise 12 complementation groups. There are a total of at least 26 mak genes. Each mak gene product is needed for plasmid maintenance in diploids as well as in haploids. None of these mak mutations prevent the killer plasmid from entering the mak- spores in the process of meiotic sporulation. Complementation between mak mutants can be performed by mating meitoic spores from a makx/+ plasmid-carrying diploid with a maky haploid. If x = y, about half the diploid clones formed lose the killer plasmid. If x not equal to y, complementation occurs, and all of the diploid clones are killers.


[Mechanism of genetic recombination in bacterial conjugation. VIII. The heterogeneity of the progeny of exconjugants].

It is shown on several examples that the heterogeneity of recombinant clones after conjugation is independent on the conditions of primary selection (i.e. on the yield of primary clones). Therefore the prediction of the model of autonomously multiplying donor fragments is not confirmed by experimental data. Two additional characteristics of heterogeneity are introduced. The statistical distribution of merozygotes according to segregation time is measured. It is an exponential curve with a relaxation time approximately coinsident with the third cell division. A liner function is found for the dependence of heterogeneity on the distance between the selective and non-selective markers. The highest value for non-linked markers is about 15%. Alternative models for the explanation of the heterogeneity of exconjugants are discussed.


[Multiple mutants of Saccharomyces cerevisiae. III. The identification of the mutational changes that occur].

Localization and molecular nature of mutations in multiple mutants of yeast Sacchromyces cerevisiae were studied. It was found that simultaneous changes in several genes located in more than five linkage groups took place during the arise of multiple mutants after a single UV-irradiation (at a dose of 300 erg/nm2). It was shown that reversions of original nonsense-mutations were due to mutational changes in the same genes and the arise of the forward nonsense-mutations in the other genes took place as a result of base changes in DNA.


[Action of ftorafur on the chromosomes of normal and tumorous cells of the Djzungarian hamster in vitro].

The chromosome-breaking effect of antitumor agent ftorafur (0,1 mg/ml) was studied on cell cultures of normal and transformed Djungarian hamster's fibroblasts. After 24 hours of exposition with the drug 79% of aberrant malignant cells was registered, while the chromosomes of normal cells remained undamaged. After ftorafur's action for 2--12 hours and the following removal of the agent the level of aberrant metaphase among normal cells rose to 11--15%. Chromatid breaks were the predominant type of drug-induced aberrations. Thse results confirm the idea that ftorafur blocks the cell cycle of normal fibroblasts and that it's necessary to wash the drug off some period before fuxation in order to reveal its chromosome-breaking effect in metaphase cells. The striking distinctions in susceptibility of normal and malignant cells to the mutagenic effect of ftorafur is partly due to the distrubances of the cell cycle caused by this drug.


[F'ColVColBtrpcys plasmid in Erwinia aroideae].

Erwinia aroideae carries a cryptic plasmid with 30 S sedimentation coefficient. Plasmid F'ColVColBtrpcys does not dissociate in E. aroideae and is replicated under stringent control since the number of plasmid copies per chromosome does not exceed one. The behaviour of F'ColVColBtrpcys plasmid in E. aroideae is characterized by (1) instability observed at both spontaneous and after EB treatment, (2) depression of plasmid genes that determine colicin synthesis.


Procoagulant activity of activated monocytes.

Endotoxin-stimulated monocytes develop a very high tissue-factor-like activity as compared to an equivalent number of monocytes in a preparation of monocyte-enriched mononuclear blood cells obtained by Ficoll-Urovision density gradient centrifugation which is not exposed to endotoxin. In monocytes which were obtained by plastic adherence from the monocyte-enriched mononuclear blood cells, the tissue factor activity was as high as in the endotoxin-stimulated monocytes.


[Pathogenesis of thrombocytopenia. 2. Distribution disorders, pseudo-thrombocytopenias].

A review of the pathogenesis of thrombocytopenias is given. The various types of thrombocytopenia are classified according to the main pathogenetic mechanisms such as reduced platelet production, increased platelet destruction and disturbed platelet distribution by splenic pooling. Finally thrombocytopenia by artefacts is discussed such as platelet satillitism and spontaneous aggregation. In the second part of the paper the differential diagnosis of several forms of thrombocytopenic purpura is presented.


[Neoplasms of the small intestine].

Tumors of the small bowel comprise only 3--6% of all tumors of the intestine. The symptoms associated with tumors of the small bowel are not characteristic at the beginning. To establish an early diagnosis one must be "small bowel conscious". Mechanical intestinal obstruction, bleeding and perforation must be kept in mind for differential diagnosis.


The amino acid compositions of the tryptic, chymotryptic and peptic peptides from the L-2 light chain of rabbit skeletal muscle myosin.

The light chain fraction was separated from rabbit skeletal muscle myosin and four kinds of light chains, L-1, L-2, L-3 and L-4 in the fraction were further isolated by column chromatography using DEAE-cellulose DE-52. After amino-ethylation, the L-2 light chain was digested with trypsin. It was also digested with chymotrypsin and pepsin, respectively, after carboxymethylation. Each of the tryptic, chymotryptic and peptic peptides thus obtained was separated and purified and their amino acid compositions were analyzed.


Henoch-Schönlein anaphylactoid purpura nephropathy: electron microscopic lesions mimicking acute poststreptococcal nephritis.

The clinical, laboratory, and histologic features of a patient with Henoch-Schönlein syndrome are presented. The skin biopsy examination showed "leucocytoclastic vasculitis." Kidney tissue demonstrated deposits of IgG, C3, and fibrinogenfibrin by fluorescence microscopy in the mesangium and the peripheral glomerular basement membrane in a granular-nodular pattern. These correlated well with areas of mesangial hyperplasia and polymorphonuclear leucocyte infiltration seen by light and electron microscopy. Several well delineated, variably sized, subepithelial electron dense deposits flanked by polymorphonuclear leucotytes adherent to the glomerular basement membrane were seen in two of the four glomeruli examined by electron microscopy. The significance of these findings is discussed. A detailed ultrastructural evaluation of patients with Henoch-Schönlein nephropathy may yield information about the frequency of subepithelial deposits and perhaps may help to clarify the pathogenesis of this syndrome.


Comparison of the direct antiglobulin rosetting reaction with direct immunofluorescence in the detection of surface membrane immunoglobulin on human peripheral blood lymphocytes.

Comparisons were made between the Direct Antiglobulin Rosetting Reaction (DARR) and Direct Immunofluorescence (DIF) in the detection of surface membrane immunoglobulin of human peripheral lymphocytes. The DARR was more sensitive and the results with this testing procedure (as opposed to those with the DIF) were not influenced by various treatments of the lymphocytes before testing, such as incubation in AB serum at +/- 4 degrees, incubation in serum-free medium at 37 degrees or short exposure to acetate buffer at pH 4.0. Again the DARR (as opposed to the DIF) gave essentially the same results whether the red cell-linked antiglobulin was IgG or the F(ab')2 preparation. With mixed rosetting for both T and SmIg+/- lymphocytes, there was only 1% or less null cells and only 5% or less lymphocytes rosetted with both marker red cells.


Effect of Vibrio cholerae neuraminidase on the phagocytosis of E. coli by macrophages in vivo and in vitro.

The mechanisms by which Vibrio cholerae neuraminidase VCN acts as an adjuvant is unclear. We have studied the effect of VCN on the phagocyotsis of E. coli 0111 K58 by macrophages in vivo and in vitro. (1) Using and in vivo intraperitoneal clearance test we have shown that prior injection of VCN (50 units/mouse) into the peritoneal cavity of mice enhances the clearance of the bacteria as efficiently as an optimal amount of opsonizing antiserum. We have also shown that the enhancement of intraperitoneal clearance by VCN is due to phagocytosis and intracellular killing of the organisms by macrophages. (2) VCN does not enhance the i.v. clearance of E. coli o111 K58. (3) VCN promotes the attachment of the organisms to and phagocytosis by peritoneal macrophages in vitro. Data are provided which suggest that the promotion of attachment and phagocytosis by VCN cannot be explained by a mere increase of passive absorption of the bacteria to the cell wall.


Purification and chemical characterization of the heat-stable enterotoxin produced by porcine strains of enterotoxigenic Escherichia coli.

Heat-stable enterotoxin (ST) produced by porcine strains of enterotoxigenic (ENT+) Escherichia coli has been purified to apparent homogeneity by sequential ultrafiltration, acetone fractionation, preparative gel electrophoresis, diethylaminoethyl Bio-Gel A ion-exchange chromatography, and Bio-Gel P-10 gel filtration. The enterotoxin, purified more than 1,500-fold, exhibited a molecular weight of 4,400, as determined by both sodium dodecyl sulfate-gel electrophoresis and gel filtration. A molecular weight of 5,100, representing 47 residues, was calculated from amino acid analysis data. The amino acid content was distinctive, with an unusually high proportion of cystines and few hydrophobic amino acids. A single amino-terminal residue, glycine, was observed. Purified ST was stable to heating (100 degrees C, 30 min) and did not lose biological activity after treatment with Pronase, trypsin, proteinase K, deoxyribonuclease, ribonuclease, and phospholipase C. Periodic acid oxidation and several organic solvents (acetone, phenol, chloroform, and methanol) had no effect on the biological activity of ST. Further, purified ST was stable to acid treatment at pH 1.0 but lost biological activity at pH values greater than 9.0. Neither lipopolysaccharide nor lipid contamination was evident in purified preparations. A characteristic absorption spectrum was observed during the course of the purification, which shifted from a maximum at 260 nm in crude preparations to 270 nm for the purified toxin. Antiserum obtained from rabbits immunized with ST or ST coupled to bovine serum albumin neutralized the action of the enterotoxin in suckling mice; however, passive hemagglutination and hemolysis titer assays suggested that ST is a poor antigen.


Cellular release of heat-labile enterotoxin of Escherichia coli by bacteriophage induction.

Treatment of some enterotoxigenic Escherichia coli strains with the antibiotic mitomycin C resulted in lysis of the bacteria. Heat-labile enterotoxin (LT) activity of culture filtrates, determined by means of the Y-1 adrenal cell assay, increased dramatically as lysis of the culture proceeded. Further studies with E. coli strains 263 and B21-4 revealed that lysis is due to mitomycin C induction of vetetative development of a temperature bacteriophage. These findings suggest that the elevated levels of LT detected after mitomycin C treatment reflect the lytic release of cell-bound LT rather than the induction by mitomycin C of de novo toxin biosynthesis. Comparable increases in LT activity also resulted from thermal induction of a phage P1Cm lysogen of strain 263 or from sonic disruption of enterotoxigenic strains.


Isoelectric point of cell-free K99 antigen exhibiting hemagglutinating properties.

The isoelectric point of the K99 antigen in partially purified preparations isolated from Escherichia coli B41 was 4.2. Electrofocused K99 antigen hemagglutinated guinea pig and sheep erythrocytes and gave a single precipitin line on diffusion against antisera to E. coli B41 and absorbed factor K99 antisera.


Characterization of a partially purified methanol-soluble heat-stable Escherichia coli enterotoxin in infant mice.

While studying the involvement of cyclic adenosine 3',5'-monophosphate (cAMP) in the fluid secretion caused by heat-stable enterotoxin (ST) from Escherichia coli P16 in infant mice, it was noted that the culture filtrate containing ST also contained large amounts of cAMP. The present paper details attempts to obtain a cAMP-free ST preparation. The organisms were grown in a defined medium, and the heated culture filtrate was concentrated by reverse osmosis. After methanol extraction of the filtrate, which removed 80% of the nonactive solids, the methanol-soluble ST was further purified by gel filtration through a Sephadex G-10 column. The first fraction recovered after gel chromatography contained ST with a negligible amount of cAMP. Treatment with methanol did not adversely affect the enterotoxic activity. Certain parameters of the infant mouse model have been investigated, and using our ST preparation it has been found that animals remain responsive up to 15 days of age with an optimum assay time of 2 h after toxin challenge.


Effects of fatty acids on motility retention by Treponema pallidum in vitro.

Treponema pallidum (Nichols virulent strain) was incubated under 75% N2 + 20% H2 + 5% CO2 in prereduced serum-free modified Eagle-Richter medium supplemented with different concentrations of various long-chain fatty acids complexed with fatty acid-free bovine serum albumin. Motility retention was greater in medium with oleic acid containing 15 rather than 2 mg of albumin per ml. Palmitic, stearic, oleic, or linoleic acid alone caused rapid loss of motility at concentrations as low as 5 microgram/ml. Elaidic acid (92 microgram/ml) alone had no effect on motility. Various combinations of saturated plus unsaturated fatty acids did not inhibit motility retention or were less inhibitory than either of the individual fatty acid components. The combination of palmitic plus oleic acids was least toxic. Rapid loss of motility occurred with pairs of unsaturated or saturated fatty acids, or with Tween 40, 60, or 80, alone or combined. Autoxidation of oleic acid resulted in decreased toxicity for T. pallidum but increased toxicity for baby hamster kidney cells.


Ribosomal ribonucleic acid synthesis by virulent Treponema pallidum.

Ribosomal ribonucleic acid (rRNA) synthesis by virulent Treponema pallidum was monitored by incorporation of [(3)H]uridine into trichloroacetic acid-precipitable counts and examination of radiolabeled rRNA on polyacrylamide gels. Verification that rRNA synthesis originated with T. pallidum was based upon co-electrophoresis with Escherichia coli rRNA, proportionate reductions in the amount of rRNA synthesized when numbers of treponemes were decreased, and inclusion of appropriate animal cell controls. The rate of treponemal rRNA synthesis was greater at temperatures of 37 and 39 degrees C than at 33 degrees C; rRNA synthesis was inhibited at 4 and 42 degrees C and was effectively inhibited by actinomycin D. Kinetic experiments indicated that the majority of rRNA synthesis occurred early after extraction of treponemes from infected rabbit testicular tissue. Polyacrylamide gel profiles demonstrated the capacity of virulent T. pallidum to synthesize and process RNA to 23s, 16s, and 4 to 5s classes. Although motility of T. pallidum appeared unaffected during longer periods of incubation, pulselabeling experiments confirmed significant reductions in the rate of rRNA synthesis. When the effect of various environmental conditions upon rRNA synthesis was investigated, optimal synthesis was found to occur in an atmosphere of 20% oxygen whereas virtually no synthesis was observed under anaerobic or low-oxygen conditions.


Effects of antibiotic resistance plasmids on the bactericidal activity of normal rabbit serum.

The ability of normal rabbit serum to kill Escherichia coli J6-2 was measured. With the concentration of serum adjusted so that approximately 2% of the cells survived after 2 h of incubation, there was no killing of the same strain bearing the F-like plasmid R100. Other F-like plasmids also provided the host strain with resistance to serum bactericidal activity, whereas none of the I-like plasmids used provided the host strain with resistance. When E. coli J6-2 bore both R100 and an I-like plasmid, there was some resistance to serum but less than with R100 alone. The effects of lysozyme on E. coli J6-2, which had been treated with tris(hydroxymethyl)aminomethane and ethylenediaminetetraacetate, were not altered by the presence of R100. The plasmids from 16 clinical E. coli isolates were transferred to J6-2N, a nalidixic acid-resistant mutant of J6-2. Four of the 16 plasmids provided J6-2N with resistance to normal rabbit serum.


Differences in serological responses and excretion patterns of volunteers challenged with enterotoxigenic Escherichia coli with and without the colonization factor antigen.

Double-blind studies were performed to compare the virulence of enterotoxigenic Escherichia coli with and without the fimbriate colonization factor antigen (CFA), using young healthy adults (mean age, 23 years) as volunteers. In the first study one group of volunteers ingested 1 X 10(6) E. coli H-10407, the CFA-positive strain, and another group ingested 1 X 10(6) E. coli H-10407-P, the CFA-negative spontaneous derivative of strain H-10407. The second study was similar except that the test strains were administered at a dose of 1 X 10(8) viable cells. Three parameters of infection were monitored: (i) diarrhea and associated symptoms; (ii) excretion pattern of test strains; and (iii) humoral antibody response to CFA, somatic antigen, and heat-labile enterotoxin. Significant signs of illness occurred only in six of seven volunteers who ingested E. coli H-10407 at a dose of 1 X 10(8). At both doses, E. coli H-10407-P appeared in the stool on day 1 postchallenge and disappeared by day 4. In contrast, strain H-10407 was persistently excreted from the first to the last day of the study. Also, only those volunteers in the H-10407 challenge groups (12 of 13 analyzed) responded with a fourfold antibody titer rise to CFA, somatic antigen, and/or heat-labile enterotoxin. No reversion of H-10407-P to H-10407 was detected.