[Liver and ovulation inhibitors. Effects on liver function of estrogen-progestagen containing steroid oral contraceptives].

Since introduction of oral contraceptive steroids a variety of physiologic-adaptive and toxic side effects have been reported. -a review is given. The study reports also four cases of hepatic vein thrombosis (Budd-Chiari-Syndrome--Venoocclusive disease) and three cases of benign hepatic tumors (liver cell adenoma and focal nodular hyperplasia) in young women following 2- to 5-year treatment with oral contraceptive steroids.


Why are enzymes macromolecules?

The possible reasons for the macromolecular nature of enzymes are discussed. They are recognized in the necessity of creating a highly specific stereochemistry and microenvironment in the active site, in the necessity of maintaining the protein conformational rigidity, its fit with the physiological environment and overall stability, in allostery, and in the possible existence of fossil sequences, molecular tinkering, and specific hydrodynamic properties.


Central and peripheral effects of bradykinin and prostaglandin E2 on blood pressure in conscious rats.

Bradykinin or prostaglandin E2 (PGE2), when injected intravenously, decreased blood pressure of conscious rats in a dose-dependent manner, while intracerebroventricular injections of bradykinin or PGE2 caused a dose-dependent increase in blood pressure. SQ 14,225, an inhibitor of angiotensin converting enzyme, potentiated the central pressor or peripheral depressor effect of bradykinin. Indomethacin, an inhibitor of prostaglandin synthesis, almost completely inhibited the central pressor effect of bradykinin when injected intraventricularly. Indomenthacin, when injected intravenously, failed to inhibit the peripheral depressor effect of bradykinin, whereas it significantly attenuated the peripheral depressor effect of bradykinin when the angiotensin converting enzyme was inhibited with SQ 14,225. These results suggest that the central pressor effect of bradykinin is mainly mediated by the synthesis of prostaglandins in the central nervous system, while only a small fraction of peripheral depressor effect of bradykinin is, at least in conscious rats, mediated by the synthesis of prostaglandins in the systemic circulation.


Migration of an entire one-piece shunt into the ventricle.

Migration of an entire one-piece shunt into the lateral ventricle of a six-month-old boy is reported. This is a rare complication in this kind of shunt, and has not previously been reported.


Sexual maturation of the male rat. Influence of androgens on the pituitary response to single or multiple injections of LH-RH.

In an attempt to mimic the events surrounding the natural onset of puberty in the male rat, animals were castrated and implanted with Silastic capsules filled with testosterone (T). Capsule size was adjusted to maintain serum-luteinizing hormone (LH) at sham-castrated values. To these animals implanted with T capsules, androstenedione (delta 4), 5 alpha-androstane-17 beta-ol-3-one (DHT), 5 alpha-androstane-3 alpha-17 beta-diol (3 alpha-OL) or T were administered by subcutaneous injections (40 micrograms/100 g body weight). 12 h later, the animals received an intravenous injection of 50 ng LH-RH. Pre- and post-LH-RH injection blood samples were assayed for serum content of LH and follicle-stimulating hormone (FSH) by radioimmunoassay. Compared to sham animals, prepubertal males showed a potentiation in the LH response with testosterone alone. This effect was not prevented by delta 4; DHT or 3 alpha-OL injection returned the LH response to that of sham-operated animals. No such effects of androgens were present in pubertal or postpubertal rats. There was no effect on the FSH response in any age group. Different groups of animals received 3 doses of 10 ng LH-RH or saline prior to a single 50 ng LH-RH injection. Pubertal and postpubertal males showed a self-priming effect of LH-RH on the LH response. This effect was not present in prepubertal rats nor in any group of animals that had been castrated, regardless of whether or not T replacement was performed. The results indicate that complex alterations in pituitary function take place during the sexual maturation of the male rat. These changes may be inherent in the pituitary and/or related to variation in testicular androgen secretion.


Sodium valproate: serial monitoring of EEG and serum levels.

The clinical and electroencephalographic (EEG) effects of sodium valproate were studied in four patients by means of serial 24-hour EEG recordings and simultaneous hourly determinations of serum drug concentrations. The patients all had frequent clinical seizures and generalized spike-wave discharges. Valproate appeared to reduce diurnal paroxysmal discharges (PD) and clinical seizures, but the effect on nocturnal PD was less marked. The extent and duration of the depression of PD and seizures varied. Altering the distribution of the total daily dose may change the pattern of clinical seizures and PD. Valproate concentrations fluctuated widely over 24 hours, and the significance of single estimations often cited in the literature appears dubious. Peak serum concentrations above 100 micrograms per milliliter may be necessary in some patients to achieve clinical and EEG improvement.


Cerebrospinal fluid and serum immunoglobulins and C3 in Creutzfeldt-Jakob disease.

We determined the concentrations of IgA, IgG, and C3 in spinal fluid and IgA, IgG, IgM, and C3 in serum from seven patients with histologically revified Creutzfeldt-Jakob disease. The mean total protein content in spinal fluid was significantly higher than in controls. The increased mean concentrations of IgA, IgG, and C3 in spinal fluid, and their respective mean percentages in spinal fluid, suggest a passage of IgG and C3 from blood into spinal fluid, and a possible production of IgA within the central nervous system.


Diagnostic evaluation of syphilis during pregnancy.

Obstetric patients with serologic evidence of syphilis should have cerebrospinal fluid (CSF) analysis to determine the presence of tertiary disease. In the present study, 19% of untreated and asymptomatic patients with serologic evidence of syphilis were found to have tertiary syphilis following examination of CSF. Despite maternal therapy, 11% of the infants born to mothers with syphilis had reactive serum and CSF involvement as documented by the presence of a fluorescent treponemal antibody absorption (FTA-ABS)-specific IgM.


The presence of Candida albicans in hereditary benign intraepithelial dyskeratosis. An ultrastructural observation.

Specimens taken from the buccal mucosa of two patients with hereditary benign intraepithelial dyskeratosis (HBID) were studied by transmission electron microscopy. The ultrastructure of epithelial tissue in HBID was previously reported. Discovery of Candida albicans in this lesion was an accidental finding. The literature on the subject was reviewed and the ultrastructural features of Candida albicans were described.


Vasoactive intestinal polypeptide nerves in human upper respiratory tract.

Immunoreactive vasoactive intestinal polypeptide (VIP), a recently recognized neuropeptide with a possible transmitter function has been demonstrated in nerves of the human upper respiratory tract. VIP nerves predominate in the inferior turbinate of the nose and in the tracheal wall. They are distributed in the subepithelial connective tissue, around blood vessels and seromucous glands. Scattered VIP nerves are observed also in the tracheal smooth muscle. VIP immunoreactive nerve cell bodies are found only in the tracheal wall, suggesting a local origin of the VIP nerves in this organ. Available information indicates that the VIP-containing nerves constitute a separate component of the autonomic nervous system in addition to the adrenergic and cholinergic ones.


Vaccinations against bacterial infections.

1. As with any therapeutic measure, prophylactic vaccination is to be jugded by the correlation between benefit and harm or expenditure. By benefit is meant a not to short-lived substantial decrease in the morbidity and/or mortality. Harm refers to the number and severity of side effects in the individual child vaccinated and expenditure means the economic burden placed upon society. 2. The evaluation of many vaccinations at present varies between two extremes: On the one hand vaccination procedures are considered to provide an opportunity to eradicate most of the infectious diseases, on the other hand there is a tendency to assess side effects more drastically the more likely the danger of the particular disease seems eliminated once and for all. 3. An attempt is made to discuss the achieved or achievable standard of vaccination measures against bacterial infections in the light of 3 classes of vaccines. The first class involves well established and commonly used vaccines such as BCG and DPT vaccines although differences in opinion exist on their future employment. 4. The second class involves newer vaccines or vaccines that are under development as for instance vaccines against meningococci, pneumococci, H. influenzae and enteropathogenic E. coli. 5. The third class includes vaccines whose realisation at present appears to be yet difficult or hardly feasible, for instance vaccines against enterotoxins of enteropathogenic organisms, against lues, gonorrhea or for example against organisms of the infectious hospitalism.


[The development of child pathology within the framework of pathology and pediatrics. A medico-historical review].

1. The history of child pathology is derived from the description of the development of the an pathological anatomy and paediatry. 2. The pathological anatomy of infancy is basing on the research results of the general and special pathology, the pathological physiology and the clinical medicine by the help of the experiment and the knowledges of biology, chemistry, and physics. 3. Further decisive impulses are given by social medicine.


Vesiculobullous lesions of the upper aerodigestive tract.

Vesiculobullous lesions of the upper aerodigestive tract are among the most frequently occurring disease processes of the oral soft tissues. Pemphigus vulgaris, mucous membrane pemphigoid, erythema multiforme, and erosive lichen planus are compared and contrasted with each other and with vesiculobullous eruptions of viral origin. Clinical photographs and photomicrographs of these disease processes are presented. Treatment modalities are briefly discussed.


An immunoperoxidase method for the demonstration of allergen-specific IgE in serum.

A solid-phase immunoenzymatic technique for the detection of allergen-specific IgE antibodies in serum is described. The binding of such antibodies to allergen insolubilized on cyanogen bromide-activated paper discs was detected by a subsequent two-step procedure involving the use of rabbit antihuman IgE and goat antirabbit IgG coupled with peroxidase. A solution of 3-3' diaminobenzidine and hydrogen peroxide, employed as the color indicator system, turned the discs dark brown in positive cases. Discs carrying 11 different inhalant allergens were tested with sera containing allergen-specific IgE antibodies. Agreement between the results of this technique and the RAST was seen in 85% of 310 tests performed. In the clinical practice of otorhinolaryngologic allergy, this test may prove to be an important laboratory adjunct ot clinical history and diagnostic skin test in the identification of the incriminated inhalant allergens.


Tracheoinnominate artery fistula as a complication of radiation therapy.

Tracheoinnominate artery fistulization is a well-known complication of tracheostomy and of tracheal resection. The first known occurrence of this problem in a patient in whom no transtracheal procedure had ever been performed is reported, and high-dose radiation therapy delivered three years before for a mediastinal malignancy is suggested as the cause. No evidence of tumor was found in or adjacent to the tracheovascular communication. The tracheoinnominate artery fistula must be considered a potential complication of radiation therapy as well as of surgery.


A double-blind controlled study of seratonin uptake inhibitor (Zimelidine) versus placebo in chronic pain patients.

Forty patients with pain syndromes of both organic and psychogenic origin of at least 6 months' duration were included in a double-blind controlled study of a new rather selective serotonin uptake inhibitor, Zimelidine, versus placebo. Patients in the Zimelidine group experienced significantly more pain relief and tended to be able to reduce their need for analgesics more often than the patients in the placebo group. In the Zimelidine group 4 patients were excluded due to nausea and intestinal troubles versus only 1 patient in the placebo group. However, among the patients who completed the trial the side-effects were mild.


Situational modification of regional flaps.

A few modifications in unusual situations of regional flaps in the head and neck are demonstrated. It is the author's hope to stimulate the surgeon to use some imagination, incorporating a variety of time-proven principles and some unique situational modifications. Emphasis is placed on the continued need for the tubed pedicle flap, de-epithelialization of flaps and imbrication about the margins of the defect, and the use of the horizontally split deltopectoral flap for the simultaneous closure of internal defects and coverage of external defects for through-and-through wounds.


[Protection of mice with bacterial phospholipids against the lethal effect of Frog Virus 3 (FV 3) (author's transl)].

A bacterial phospholipid extract (EBP) inoculated intraveinously at a dose of 1 mg/25 g body weight 30 hours before infection protects mice against the lethal effect of Frog Virus 3 (FV 3). The anti-FV 3 resistance produced by EBP requires protein synthesis during the period of pretreatment. The treatment with the bacterial extract has no effect on the inhibition of the macromolecular synthesis of the liver (RNA and DNA) which is observed at the beginning of the infection. However 48 hours after FV 3 infection, there is a notable stimulation of DNA synthesis which probably corresponds to liver regeneration.


[Serological diagnosis of Staphylococcus aureus infections using anti-A beta teichoic acid antibodies assay (author's transl)].

225 control subjects, 12 hospitalized Staphylococcus free (34 sera) and 16 S. aureus infected patients (79 sera) were tested for anti-A beta teichoic acid antibodies, using counter-immunoelectrophoresis. Anti-alpha and gamma haemolysins antibodies were dosed in parallel in 164 sera. Less than 5 per cent of control sera (3,11 per cent) have an antibody tire higher than 1/8: this tire is therefore selected as threshold level of positivity. Ten of the 12 hospitalized patients without staphylococcal infections are below this level. 31,6 per cent of staphylococcus infected patients have higher serum titers; only 3,7 per cent have no antibodies. In the others, a significant rise in titres is observed. There is no correlation between anti-alpha and gamma staphylolysin and anti-teichoic acid antibodies titres. The method suggested, both easy and rapid, could be used in association with anti-staphylolysin dosage for serological diagnosis of staphylococcal infections.


[Action of methicillin on the synthesis of surface protein A and type antigen 18 in Staphylococcus aureus].

Staphylococcus aureus methicillin resistants strains cultivated on subinhibiting methicillin concentrations are not modified as concern protein A and type antigen 18. Low protein A production of these resistant strains known to be heterogenous as concern their resistance to methicillin does not correspond to absence of protein A on the highly resistant fraction of the population.


Measurement of bismuth in bone by pulse polarography with anodic stripping voltammetry. Application to two cases of arthropathy.

Pulse polarography with anodic stripping has shown the presence of very high levels (2 005 microgram/kg and 6 760 microgram/kg) of bismuth in bone of two patients treated with bismuth, one parenterally and the other orally. The presence of high levels of bismuth in bone of these patients must be considered in the etiology of their athropathies. Pulse polarography with anodic stripping now permits very precise measurement of bismuth impregnating bones.


[Biochemical and experimental aspects of the lipid-lowering drugs pharmacology (author's transl)].

The analysis of the mode of action of lipid-lowering drugs requires a better understanding of the lipoprotein and cholesterol metabolism processes. The strides observed during the last years in this field are conditioning the development of pharmacologic and therapeutic researches. Moreover the use of new experimental models contributes to this progress by multiplying the study ways.


[Modified method for assay of cephalosporins and cephamycins (author's transl)].

An improved microbiological method for assay of cephalosporins and cephamycins in body fluids is presented. Addition of NaCl and NaCt resulted in increasing the precision and reliability of the assay.


The role of total body irradiation in preparation for bone marrow transplantation in acute leukaemia. A review.

From extrapolation obtained from animal studies and radiation accidents, it is assumed that for man the LD 50 (30) will be between 300-500 rads total body irradiation (TBI) and the LD 100 at least 600 rads TBI. A dose of 1000 rads TBI is generally used in man for conditionning for bone marrow transplantation. In acute leukemia, total body irradiation is usually associated with cytoreductive chemotherapy. In Seattle 110 patients underwent bone marrow transplantation for acute leukemia in relapse. 15 patients became long term survivors. The main cause of failure were GVH, interstitial pneumonitis and leukemic relapse. New attempts are being made to improve the results : (1) better cytoreductive therapy preceding transplanation, (2) bone marrow transplantation during remission of the disease, (3) prevention of interstitial pneumonitis by modifications of the TBI technique.


Total body irradiation in bone marrow transplantation. Hôpital Saint-Louis results.

Total body irradiation was used in 22 patients as part of their conditionning regimen for bone marrow transplantation. Nine patients with acute leukemia received 1 000 cGy TBI in addition with chemotherapy. None of them survived and the main cause of death was interstitial pneumonitis (50%). 4 patients received 1 000 cGy with a lung shielding of 500 cGy. Two patients with acute leukemia died of leukemia and sepsis, two patients had aplastic anemia, one is surviving, the other died of severe GVHD and infectious complications. Nine patients with severe aplastic anemia strongly immunized by previous blood transfusions received 800 cGy TBI with a lung shielding of 400 cGy. No rejection was observed and 7 patients (63%) are currently alive. One patient died of interstitial pneumonitis probably related to CMV infection, one of subacute necrotizing hepatitis, two of severe acute GVHD. It is concluded from this study that TBI remains the best immunosuppressive conditioning regimen even in strongly immunized patients. It may be a contributing factor of the incidence and severity of interstitial pneumonitis. A reduction of the dose ot the lung to 400-500 cGy seems to decrease the severity of this complication.


The Basel experience with total body irradiation for conditioning patients with acute leukemia for allogeneic bone marrow transplantation.

We are reporting our experience with 13 patients suffering from end stage acute leukemia that were prepared for allogeneic bone marrow transplantation by combined chemotherapy followed by high dose cyclophosphamide (Cy) and total body irradiation (TBI). Only one patient became a long term survivor. Of the evaluable 12 patients, 6 died of interstitial pneumonia, 4 of GvH and 1 of recurrent leukemia. We conclude that adding combined chemotherapy to the standard conditioning program with Cy and TBI probably increases the risk of developing fatal interstitial pneumonia without eliminating the risk of recurrent leukemia. We suggest that allogenic marrow grafts should be performed earlier in the course of refractory acute leukemias, because in patients with end stage disease its chances of being curative are small.


Total body irradiation and marrow transplantation for acute leukaemia. The Royal Marsden Hospital experience.

The experience with total body irradiation at the Royal Marsden Hospital is described for an elective program of transplantation in patients with acute myeloid leukaemia (AML) in first remission. Dose rate appears to be a critical factor in the reduction of radiation-associated damage and careful monitoring of the actual dose distribution and dose received is mandatory.


Subtotal body irradiation with linear accelerator as preparation for marrow engraftment in aplastic anemia.

Two cases of multitransfused severe aplastic anemia were retransplanted with bone marrow from the same HLA compatible sibling donors after subtotal body irradiation (800 r). Only minor non hematologic toxicity was observed. No permanent take was seen in relation to this procedure. During the survival time of the patients (78-120 days) no signs of interstitial pneumonia were observed.


Total body irradiation in conditioning patients for bone marrow transplantation. Irradiation technique and preliminary results at the West German Tumour Centre, Universitätsklinikum Essen.

Preliminary results of bone marrow transplantation of 8 patients are presented with particular reference to the irradiation technique. 5 patients died 0.5 to 8 months after transplantation. 3 patients are alive and in good condition 2 to 15 month after transplantation.


Time factors in total body irradiation.

The role of time dose factors in the irradiation effect of the bone marrow has been investigated in mice by assessing the lethal dose 50% as a function of fraction number and dose rate. It is compared to the time dose effect in intestinal mucosa and lung, considered as critical tissues, for discussing the differential effect between these tissues.


Total body irradiation techniques and dosimetry.

Irradiation techniques and dosimetric methods used for total body irradiation (TBI) performed at Institut Gustave Roussy (Villejuif) are presented. TBI are performed in a 5,6 MV X-ray beam produced by a linear accelerator Neptune. The patient, lying laterally on a couch at 4.20 m from the target, is irradiated by a horizontal beam with a mean nominal dose rate at the abdomen mid-plane of about 9 cGy per minute. The procedure used for TBI consists of three parts in order to deliver 8 Gy in the whole body except for lungs which are protected with a lead screen during a part of irradiation and receive a dose of 4 Gy. We have preferred using "in vivo" measurements methods rather than calculations to determine the doses at different points of the patients. Two kinds of detectors are placed on the patient's skin all along the total body irradiation : two sets of five Therados semi conductors probes permit to control the irradiation and lithium fluoride thermoluminescent dosimeters are used like reference detectors. The dosimetric results obtained during the TBI performed at IGR are discussed.


[Relationship between intestinal motility and absorption. Electromyographic study in the dog. (author's transl)].

The effects of different food components on intestinal motility were studied by means of an electromyographic technique. The electrical activity of the small intestine in the fasted state consists of a cyclic recurring phenomenon - the myoelectric complex - which is inhibited by feeding. The duration of inhibition of the myoelectric complex was shown to depend on the nature of the food components (glucose, peptides or lipids) as well as on the caloric load. In the opposite, the intensity of the intestinal motility was seen to depend only on the nature of the food components, and not on the caloric load. Thus, the duration of inhibition of themyoelectric complex can be considered as a consistent and objective parameter, which reflects the duration of the fed state.


[Breast cancer: a dynamic approach of cellular immunity and immunostimulation with an immunoadjuvant: P40 fraction. (author's transl)].

The study of the immune status of breast cancer patients with delayed hypersensitivity skin tests reveals a clear immune deficiency in comparison with a reference patients group. This immunstatus was significantly improved by an immunstimulation with the P40 fraction. The responsive capacity to an immunstimulation appears independant of the lymphnodes involvment, whereas, on the contrary, the initial degree of immune deficiency appears connected. The P40 fraction has an immunstimulant effect comparable with the BCG and has not occasioned any local or general undesirable reaction.


[Evaluation of the biliary excretion of penicillin G. (author's transl)].

Biliary excretion of penicillin G was studied experimentally by perfusion of isolated rabbit liver. Under these conditions, bile recovery accounted for 5% of the amount of penicillin G added to the perfusing blood (10 mg); peak biliary level averaged 135.3 micrograms/ml. In man after intravenous administration of a 599 mg dose of penicillin G (1 MU) to patients provided with T-tube drainage (n = 10), the maximum biliary concentration averaged 18.0 +/- 8.0 micrograms/ml at 2 hours; biliary recovery of penicillin G accounts for 0.12% of the administered dose. The excretion of penicillin G in the juice collected through duodenal tubing in normal subjects averaged 0.07% of the administered dose (599 mg IV). Per-operative assays showed that the concentration determined at 1 hour after intravenous administration of the drug (599 mg) in the gallbladder bile (45.7 +/- 16.7 micrograms/ml) and common duct bile (93.5 +/- 16.3 micrograms/ml) were definitely higher (4.5--9 times) than the serum levels measured simultaneously. The biliary excretion of penicillin G is compared with the biliary elimination of a certain number of beta-lactam derivatives studied under the same conditions (ampicillin, metampicillin, carbenicillin, cefalothin, cefaloridine, cefacetrile, cefalexin, cefazolin).


[Metabolism and kinetics of ampicillin elimination in cirrhosis. Therapeutical consequences. (author's transl)].

In cirrhotic patients, the authors studied the modification of the pharmacokinetics of ampicillin in the plasma and in the ascitic fluid, as well as its concentration in the urine. The influence of the jaundice, the ascites and diuretics were studied. In cirrhosis, dilution and elimination of the antibiotic are modified, as is shown by the increase in T 1/2 alpha and T 1/2 beta. These anomalies seem to be due essentially to modifications in the distribution volume; the degree of hepatocellular insufficiency does not appear to be of importance. The ascites acts as an independent compartment, into which the antibiotic's passage in slight. The practical consequences are the following: less frequent injections, increasing of the fractionated doses, in situ injections of ampicillin in cases of infection of the ascitic liquid.


[Fecal and urinary elimination of bismuth after parenteral administration. (author's transl)].

The authors compare urinary and fecal elimination of intra-muscularly administered bismuth in rats during short term and long term experiments. The fecal elimination seems to be equally important as the urinary one. They also study distribution of bismuth among different organs. The excretion by digestive tractus is mainly located in ileum ans caecum. The biliary excretion of bismuth has an apparent maximum transport. The authors check some of their results in man.


[Acquired idiopathic sideroblastic anemia (author's transl)].

The authors consider the clinical and biological data of Acquired Idiopathic Sideroblastic Anemia (AISA). The physiopathology of the syndrome is discussed; the relationships between pathologic sideroblastosis, dyserythropoiesis and ferrokinetic modifications are pointed out. The associated abnormalities of granulocytic and megacaryocytic series linked AISA to other myelodysplasia.


A method of assaying cortisol without extraction and in 1 microliter of plasma.

A simplified method is described for the assay of cortisol in human plasma. It is based upon tryptic hydrolysis of cortisol binding proteins in the plasma followed by radioimmunoassay. Only 1 microliter of plasma is used, no extraction of the hormone is necessary and most of the procedure is amenable to automatization. The sensitivity of the method is 10 pg, the coefficient of variation is 8.7% intrassay and 11.5% in different assays. The accuracy and the specificity were also verified. Comparison of this simplified technique with a standard method (extraction by methylene chloride and radiocompetition with corticosteroid binding globulin) gave a correlation coefficient (r) of 0.964.


[Effects of two drugs substituted o-anisamides: sulpiride and sultopride on the sleep awakening cycle (author's transl)].

The study of the sleep awakening cycle was carried out on implanted cats free of their movements, which received separately each drug in long lasting intake, in order to differentiate their behavioural and electrophysiological activities. The qualitative and quantitative changes induced by these o-anisamides are reported. Like in man, sulpride was found to be quite an original substance. It may be distinguished from the other psychotropic drugs studied because it has no effect on the sleep awakening cycle. The effects of sultopride are comparable with those of some neuroleptics, although its both incisive and sedative activity is very special. The neurophysiological results are discussed in the light of other studies and clinical data.


Defective activation of the third component of complement in the sera of newborn infants.

The activation of the terminal complement components, C3--9, plays an important role in the host's defense against infection. In the present study, the ability of bacteria to activate the third component of complement (C3) in newborn serum was examined. A variety of bacteria were incubated in test sera at 37 degrees C for 30 min and the percent of available C3 that was activated was measured. Using one strain of Escherchia coli (no. 3), 32% (mean) of the available C3 was activated in sera from 18 newborns, as compared to 85% in sera from their mothers and 79% in sera from 13 normal adults (P less than 0.005). In contrast, using another strain of E. coli (N70), the percent of C3 activated in newborn sera (83%) was the same as in sera from their mothers (81%) or in sera from normal adults (73%). The defective activation of C3 in newborn sera by E. coli was not related to the presence of the K1 antigen. Newborn sera were also challenged with other bacterial species and the activation of C3 was deficient when tested with klebsiellae, but not with staphylococci or streptococci. The defect in newborn sera appeared to be due to a deficiency of a serum factor rather than to the presence of an inhibitor.


Protease inhibitors in human milk.

Protease inhibitors (inhibiting trypsin, chymotrypsin, and elastase) were demonstrated in human milk from birth to 4 months after delivery. No pepsin inhibitor was found. The protease inhibitors were localized in the alpha 1-region--inhibiting trypsin, chymotrypsin, and elastase--and in a more cathodal region--inhibiting chymotrypsin--in agarose gel electrophoresis of human milk. alpha 1-antitrypsin and antichymotrypsin were demonstrated by crossed immunoelectrophoresis. Electroimmunoassay showed the concentration of alpha 1-antitrypsin in 1st day milk to be 10.9% and the concentration of antichymotrypsin was 116% of that of adult serum. The concentrations decreased during the 1st wk; from 1 wk to 4 months they were 1.6% for alpha 1-antitrypsin and 3.8% for antichymotrypsin of those of adult serum. One ml of human milk from the first 3 days inhibits, by enzymatic methods, 0-150 microgram (mean value, 70 microgram) trypsin. Milk from 1 week after delivery and later inhibits 0-65 microgram (mean value, 38 microgram) trypsin per ml.


Neonatal cellular and humoral immunity to group B streptococci.

The mechanisms of host resistance to group B streptococci have not been defined precisely. In the studies reported here we have assessed the contributions of both humoral and cellular factors in protection against strains of this group. With assays of specific opsonic activity based upon the production of polymorphonuclear leukocyte chemiluminescence and radiolabeled bacterial uptake, we have demonstrated that specific heat-stable antibody and the classic complement pathway are major factors in opsonization of these organisms. In the absence of specific antibody, fresh serum resulted in markedly reduced bacterial uptake indicating, at best, a minor role for the alternative complement pathway. Additional studies have indicated that strain-specific antiphagocytic factors as well as type-specific ones may play a role in the virulence of these organisms. Neonates who developed group B streptococcal sepsis usually lacked opsonic activity in their infecting strain. In addition, polymorphonuclear leukocytes from normal term and stressed neonates showed impaired metabolic activation as measured in the chemiluminescence assay following exposure to opsonized group B streptococci. These results suggest that neonates who develop group B streptococcal disease may have defects in both the humoral and cellular aspects of their acute inflammatory response which may contribute to the high mortality observed in this most fulminant of bacterial infections.


A finite state model for meditation phenomena.

Various reports of brain wave synchrony during Transcendental Meditation have appeared in the literature and have been interpreted as indicating a heightened state of integration of brain function. We suggest that this observed synchrony rather than indicating a greater integration of brain function might be an artifact of parts of the brain acting like a finite state machine. The finite state model is developed, its properties derived and a test for the hypothesis is presented.


[When should peripheral nerves be grafted? (author's transl)].

In the presence of peripheral nerve damage, the only acceptable procedure is suture without tension, carried out under excellent conditions of fascicular approximation. In the case of loss of substance, immediate or secondary suture should never be performed. In the experience of "S.O.S. Main" secondary suture has led to the most disastrous results. Nerve graft, as an emergency, is legitimate in the case or reimplantations, in view of the high degree of technical competence of the teams, and the experience acquired. Deffered nerve graft is envisaged at about the end of the second month:--either in the absence of suture,--or in the absence of recovery. When there is any doubt, further examination at the 4 th or 5 th month ensures that treatment is not delayed too long. At all events, examinations must be repeated every two months in order to study nerve regrowth and to determine the need for possible though difficult reoperation if it stops.


Review: ethidium fluorescence assay. Part II. Enzymatic studies and DNA-protein interactions.

Almost all DNA and RNA metabolizing enzymes can be assayed rapidly and very sensitively by exploiting the enhanced fluorescence of ethidium intercalated into duplex DNA or RNA. Denatured DNA and natural RNAs contain duplex regions due to intramolecular hydrogen-bonding and can also be sensitively measured. Where the product is truly single-stranded (e.g. dTn) it can be assayed by adding the appropriate complementary strand (e.g. dAn or rAn). Some of the assays described provide information not readily obtained by other assay procedures. Among the enzymes readily assayed are DNA and RNA polymerases, terminal deoxynucleotidyl transferases, nucleases of all varieties (e.g. single-strand specific, endonucleases including for example AP endonucleases, exonucleases, RNase H, etc.), ligases, topoisomerases including gyrases, and indirectly enzymes such as proteases and superoxide dismutase. DNA binding proteins such as histones and helix destablizing proteins can also be quantitatively assayed.


Gene expression in vitro of colicin El plasmid.

Among eighteen polypeptides synthesized in vitro from colicin El plasmid, one of the major products with a molecular weight of 59,000 was identified as colicin El by its immunological property, molecular size, and biological activity. In addition to this polypeptide, seven other polypeptides reacted with colicin El antiserum. Using EcoRI-cleaved colicin El DNA, a 56,000 dalton polypeptide of truncated colicin El was synthesized, but no polypeptide that reacted with colicin El antiserum was produced from SmaI-cleaved colicin El DNA. This fact indicates that the direction of transcription of colicin El structural gene is from SmaI site to EcoRI site in vitro. The immunity protein of a molecular weight of 14,300 and a component of relaxation proteins of a molecular weight of 64,000 were deduced by comparing the results of the gene expression in vitro of one-half (pAO100) and a quarter (pAO2) of colicin El plasmid. The directions of transcription-translation in the genes on the plasmid were discussed. The colicin El plasmid appears to have at least three transcriptional units.


A rhelogical separator for very large DNA molecules.

We present a rheological separation method for DNA molecules in which their deformability is used to advantage. This is the "radial migration method"; here we present experimental verification of the principle, theory having been reported elsewhere. The main conclusions are: (1) the theory is reasonably good; (2) radial migration is highly sensitive to the molecular weight, as predicted, and (3) intact T2 DNA (1.25 X 108 daltons) can be made to migrate about three centimeters in less than three hours.


Production of specific site probes of tRNA structure by enrichment with carbon 13 at particular locations.

Escherichia coli C6 rel met cys was cultured in a stringently defined minimal medium containing 13C-enriched metabolites in order to (1) achieve maximal 13C isotopic enrichment of tRNA; and (2) produce site specific but natural, non-perturbing NMR probes of tRNA structure and function. Growth conditions were manipulated to achieve optimal culture growth concomitant with maximal in vivo incorporation of various 13C-enriched nucleic acid precursors, including L-[methyl-13C] methionine, [2-(13)C] adenine, and [2-(13)C] uracil. Effective blockage of purine biosynthesis de novo was accomplished with the addition of the antimetabolite 6-mercaptopurine to the growth medium. Transfer RNAs specifically 13C-enriched in all methyl groups (57 atom %), C2 of adenine (60 atom %), and C2 of uracil (82 atom %) and C2 of cytosine (73 atom %) have been produced.


Interaction between RNA polymerase and a ribosomal RNA promoter of E. coli.

The interaction between RNA polymerase and the E. coli ribosomal (r) RNA promoter(s) of the rrnE operon has been studied by the filter-binding method. The extent of complex formation between RNA polymerase and rrnE promoter(s) is salt-dependent; ppGpp specifically inhibits interaction of RNA polymerase with the rrnE promoter(s). A tentative model is proposed for the molecular events in the early steps of rRNA initiation: a transition of the primarily formed, labile RNA polymerase-rRNA promoter complex to a more stable form is the determining step. This step is salt-sensitive; ppGpp acts on this "isomerization".


Is UAA or UGA part of the recognition signal for ribosomal initiation?

In none of the 92 published prokaryotic sequences is a translation codon preceeded by UAG as the first "termination codon". In most cases the UAA or UGA is close to the initiation codon and may be part of the ribosome recognition signal.


Determination of base pairing in Escherichia coli and Bacillus stearothermophilus 5S RNAs by infrared spectroscopy.

The extent of base pairing in Escherichia coli and Bacillus stearothermophilus 5S RNAs was determined by infrared spectroscopy. From the infrared spectra taken at 20 degrees and 52 degrees C it is concluded that E. coli and B. stearothermophlius 5S RNAs possess a large number of base pairs (Table I). Comparison of our results with those previously published using other methods leads to the conclusion that the structures of prokaryotic 5S RNAs involve a large number of tertiary interactions, in which the base pairing is not necessarily solely of the Watson-Crick type.


The influenza virus haemagglutinin gene: cloning and characterisation of a double-stranded DNA copy.

A protocol has been developed for the synthesis of a double-stranded DNA (dsDNA) copy of the influenza virus RNA genome segment which codes for the major surface antigen, haemagglutinin (HA). This dsDNA copy was inserted, after digestion with S1 nuclease and poly (dC) tailing with terminal transferase, into poly(dG)-tailed, PstI-cut, pBR322 DNA, and used to transform E. coli RR1. Tetracycline-resistant bacterial colonies were screened for the presence of plasmid containing the copied HA gene by testing their ability to hybridise to a specific, 32P-labelled, single-stranded DNA probe. Four cloned hybrid plasmids, containing DNA complementary to the HA gene of the influenza strain 29C (a laboratory derivative of influenza A/NT/60/68 (1)) were analysed by restriction enzyme mapping. Each contained a dsDNA insert equivalent to a full length copy of the HA gene. The nucleotide sequence of a selected restriction fragment from the DNA inserted in one of these cloned plasmids (C89) was determined. The amino acid sequence deduced from these data agreed with the amino acid sequence determined for the corresponding region of HA from the influenza strain A/Mem/102/72, another member of the Hong Kong subtype, identifying the inserted dsDNA of C89 as an authentic copy of the influenza HA gene.


A unique method utilizing antinucleotide antibodies for evaluating changes in the levels of modified nucleosides of tRNAs from crude extracts of whole cells.

The utilization of antibodies directed toward modified nucleosides in evaluating changes in the levels of certain modified nucleosides in transfer RNA is reported. Antibodies directed toward the N6-(delta 2-isopentenyl)adenosine modification were used in this model system with a mutant strain of Escherichia coli designated ipaA. The procedure is rapid, sensitive, and specific. In addition, it does not depend on the existence of an in vitro remodification system or any radiochemical labeling of the tRNA. By varying the extraction technique, the method could be applied to procaryotic or eukaryotic cell lines. The existence of antibodies specific for other nucleoside modifications makes this a system that is potentially applicable to a variety of deficiencies in the modification of both tRNA and rRNA.


Structure of cloned ribosomal DNA cistrons from Bacillus thuringiensis.

A library of B. thuringiensis DNA has been prepared by using the plasmid pBR322 as a cloning vehicle and E. coli as a host cell. By screening this collection with specific probes, 17 clones were identified whose hybrid plasmids contain rRNA genes of B. thuringiensis. Several of these plasmids have been mapped with restriction endonucleases and by DNA-RNA hybridization. By using maps of overlapping fragments, we have been able to establish an overall map of the ribosomal gene cluster.


Plasmid replication functions. IV. Promoters in the replication region of plasmid R6-5.

Eight RNA polymerase binding sites have been shown to map within the EcoRI fragment E-2 (replication region RepA EcoRI fragment) of plasmid R6-5 and all but one have been shown to contain active promoters of transcription. Three of the identified promoters are located within a 2.7 kb region essential for controlled, autonomous plasmid replication and may be involved in the functional expression of the three R6-5 replication determinants that have thus far been identified, namely the origin of vegetative replication, oriV, the replication control gene, cop, and the determinant of an essential, positive-acting element, designated RepA.


Fine structure of ribosomal RNA. II. Distribution of methylated sequences within Xenopus laevis rRNA.

The distribution of methyl groups in rRNA from Xenopus laevis was analyzed by hybridization of rRNA to subfragments of either of two cloned rDNA fragments, X1r11 and X1r12, which together constitute a complete rDNA repeat unit. Using a mixture of 3H-methyl plus 32P-labelled rRNA as probe, the molar yield of methyl groups per rRNA region in hybrid could be calculated. For this calculation the length of the rRNA coding region in each DNA subfragment is needed, which was determined for X1r11 subfragments by the nuclease S1 mapping method of Berk and Sharp. The results show that both in 18S and 28S rRNA the methyl groups are nonrandomly distributed. For 18S rRNA, clustering was found within a 3' terminal fragment of 310 nucleotides. For 28S rRNA, clustering of methyl groups was found within a region of 750 nucleotides in length, which ends 500 nucleotides from the 3' end. In contrast, the 28S rRNA 5' terminal region of 900 nucleotides is clearly undermethylated. The general position of methyl groups in 28S rRNA correlates with the location of evolutionarily conserved sequences in this molecule, as recently determined in our laboratory.


A rapid alkaline extraction procedure for screening recombinant plasmid DNA.

A procedure for extracting plasmid DNA from bacterial cells is described. The method is simple enough to permit the analysis by gel electrophoresis of 100 or more clones per day yet yields plasmid DNA which is pure enough to be digestible by restriction enzymes. The principle of the method is selective alkaline denaturation of high molecular weight chromosomal DNA while covalently closed circular DNA remains double-stranded. Adequate pH control is accomplished without using a pH meter. Upon neutralization, chromosomal DNA renatures to form an insoluble clot, leaving plasmid DNA in the supernatant. Large and small plasmid DNAs have been extracted by this method.


Modified polynucleotides. IV. Template activity of 5-alkyluracil-containing poly [d(A-r5U)] copolymers for DNA and RNA polymerases.

The change of templating properties for E. coli DNA and RNA polymerases of poly[d(A-r5U)] copolymers on substitution of the uracil for 5-methyl-, 5-ethyl-, 5-n-propyl-, 5-n-butyl- or 5-n-pentyluracil, resp., was studied. All modified polymers proved to be more effective template-primers than poly[d(A-U)] or poly[d(A-T)] for the DNA polymerase. Direct dependence of the template-primer efficiency (vmax/Km) value on the thermal stability of the polymers was observed. For transcription the r = ethyl and n-propyl polymers were also more effective templates than poly[d(A-T)].


RNA-linked nascent DNA pieces in phage T7-infected Escherchia coli. II. Primary structure of the RNA portion.

Short DNA chains were purified from phage T7 infected E. coli cells and 5' ends were labeled with 32P. By an alkali-treatment, pNp's rich in pAp and pCp were liberated from the T7 short DNA chains. After digestion of the [5'-32P] short DNA with the 3' to 5' exonuclease of T4 DNA polymerase, [5'-32P] mono- to pentaribonucleotides tipped with a deoxyribonucleotide residue at their 3' ends were isolated. 5' terminal ribonucleotides were; exclusively AMP in the penta- and the tetraribonucleotides, mostly CMP in the triribonucleotide and mainly CMP and AMP in di- and monoribonucleotides. The 5' terminal dinucleotide of the penta- and the tetraribonucleotides was pApC. The nucleotide sequence of the tetraribonucleotide was mainly pApCpCpN and some pApCpApN, where N was mainly A and C. These results indicate that oligoribonucleotides shorter than trinucleotide may result from in vivo degradation of the tetra- and pentaribonucleotides. A possibility that the tetra- and pentaribonucleotides with a 5' triphosphate terminus are the intact primers for the discontinuous T7 DNA replication is discussed.


RNA-linked nascent DNA pieces in phage T7-infected Escherichia coli. III. Detection of intact primer RNA.

RNA-linked DNA fragments of T7-infected Escherichiacoli were labeled with [(32)P]orthophosphate invivo. The RNA segments of the labeled fragments were isolated by degrading the DNA portion with the 3'--> 5' exonuclease intrinsic to bacteriophage T4 DNA polymerase and fractionated according to net charge by a DEAE-Sephadex A-25 column chromatography in the presence of 7 M urea. Tri-, tetra- and pentanucleotides were obtained which have ATP residues at their 5' ends. Most of the pentanucleotides had a single deoxynucleotide at the 3' end but a minor portion was totally an oligoribonucleotide. In the light of prior results, the former is a cooligomer of an intact tetraribonucleotide primer and a monodeoxynucleotide and the latter is an intact pentaribonucleotide primer. Tri- and tetraribonucleotides with ATP at the 5' ends had no deoxynucleotide at the 3' ends, therefore it is not clear if intact triribonucleotide primers are present. The 5'-terminal dinucleotides of the tetra- and pentanucleotides were mostly pppApC and a trace amount of pppApA was present.Images


[Multi-parameter evaluation of cerebral perfusion curves in cerebrovascular diseases results of computer-assisted radionuclide angiography (author's transl)].

The validity of computer-assisted radionuclide angiography was assessed in 189 patients with cerebrovascular disease including TIA (transient ischemic attack), PRIND (prolonged reversible ischemic neurological deficit), completed stroke and a-v. angioma. Time-activity curves were derived from regions of interest established over the right as well as the left side vascular supply territories of both middle and anterior cerebral arteries. Employing Fortran programs, parameters (right to left) A (ratio of maximal count rates), B (ratio of mean count rates) and C (relative perfusion efficiency) were computed. In patients with completed stroke, C revealed 85% and combined evaluation of A and C, 93% correct positive findings as compared with clinical and/or angiographic findings. In patients with asymptomatic stenoses, TIA and PRIND, C revealed an overall sensitivity of 83%, but was correct positive in unilateral extra- and intracranial vascular abnormalities in 96%. Out of seven a-v. angioma, five were diagnosed correctly by parameter C. These high success rates indicate the usefulness of computer-assisted radionuclide angiography (CARNA) supplementary to visual evaluation in patients suspected of having stenoses or occlusion of the major extra- or intracranial cerebral arteries.


[Typical presentation of sequential scintigraphy images in the diagnosis of cyanotic heart disease in the newborn, using a computer-assisted imaging technique (author's transl)].

The technique of sequential scintigraphy in investigating newborn infants in order to exclude or detect cyanotic congenital heart disease has been improved. The primary scintigraphic data are recorded digitally (list mode, 1 ms, 128 by 128 pixels) and evaluated automatically as a sequence of 1/2 s frames in 1/8 s increments. A 35 mm film is exposed to a scanning pulsed light spot on a CRT-screen with quantitative correspondence between local count density and the local number of light pulses. A series of highly resolved images of the rapidly changing scintigraphic pattern is achieved in 30 min. The results of 3 investigations are discussed. They prove the importance of adequate spatial resolution and definition in time in nuclear angiocardiography in infancy. Three case results are discussed in detail. In one case cardiac catheterisation and angiocardiography had been omitted, since the radioisotopic findings excluded cyanotic congenital heart disease. Two further investigations are discussed with reference to the findings at cardiac catheterisation.


A double-blind study of tienilic acid with two year follow-up of patients with mild to moderate essential hypertension.

In a double-blind study, thirty patients having mild to moderate essential hypertension were randomly assigned to a six week regimen of either tienilic acid, hydrochlorothiazide, or placebo. Blood pressure was significantly reduced with tienilic acid and hydrochlorothiazide although more so with tienilic acid. Serum uric acid declined strikingly with tienilic acid and increased significantly with hydrochlorothiazide. Serum potassium declined slightly with tienilic acid but more so with hydrochlorothiazide. Serum creatinine and blood urea nitrogen increased slightly more with tienilic acid than with hydrochlorothiazide. There were no clinical adverse effects to any of the medications during this study. Twenty-four months of continuous administration of tienilic acid revealed maintenance of blood pressure effect, but with slight increases in blood urea nitrogen, serum creatinine and uric acid and slight decreases in serum potassium as compared to six weeks administration. Tienilic acid appears to be a useful new antihypertensive agent. The hypouricaemic effect is profound and strongly suggests the need for continuing evaluation of this compound because of its unique combination of diuretic, antihypertensive and hypouricaemic properties.


Propranolol and tienilic acid in essential hypertension.

Sixteen patients with moderately severe essential hypertension completed a double-blind crossover trial with four treatment periods each lasting for six weeks. They received in random order, placebo; tienilic acid 250 mg/day; propranolol 80 mg b.d.; and tienilic acid 250 mg/day and propranolol 80 mg b.d. in combination. Mean blood pressure in the lying position was 169/98 mmHg on placebo, 157/94 mmHg on tienilic acid, 159/90 mmHg on propranolol and 142/86 mmHg on the combination of tienilic acid and propranolol. The effects of tienilic acid and propranolol on blood pressure were additive and there was no evidence of any interaction. The onset of the hypotensive effect of tienilic acid was gradual while the effect of propranolol was maximal within 2 weeks of the start of treatment. Tienilic acid produced a significant reduction in serum urate from 0.33 mmol/l to 0.18 mmol/l. The combination of tienilic acid and propranolol in the doses used in the trial was effective and acceptable in the reduction of raised blood pressure.


Long-term usage of tienilic acid in essential hypertension.

The purpose of this double-blind study was to compare the effects on blood pressure of tienilic acid and hydrochlorothiazide in patients with essential hypertension. The biochemical effects of tienilic acid in relation to those of hydrochlorothiazide were also determined over a long-term period of therapy. Sixty-six outpatients with mild to moderate essential hypertension were treated for seven months with either 250 mg of tienilic acid or 50 mg of hydrochlorothiazide after a 3 week placebo period. When warranted, dosage was increased to a maximum of 500 mg of tienilic acid and 100 mg of hydrochlorothiazide daily. Results indicate that tienilic acid reduced blood pressure significantly and to the same extent as hydrochlorothiazide. No significant side effects were observed. The effects on potassium, blood urea nitrogen and creatinine were comparable in both groups. However, serum uric acid rose with hydrochlorothiazide but fell with tienilic acid. In view of this effect, tienilic acid may have certain advantages over thiazide therapy in the treatment of hypertension.


Safety of tienilic acid.

The safety and efficacy of tienilic acid have been evaluated in studies of patients with mild to moderate essential hypertension, salt and water retention states and hyperuricaemia associated with gout. During the course of these studies 675 patients were treated with tienilic acid, 310 were treated with hydrochlorothiazide, 43 were treated with probenecid and 34 were treated with placebo. Overall, adverse reactions characterized as probably drug-related or questinably drug-related were reported in 28% of patients treated with tienilic acid, 24% treated with hydrochlorothiazide, 25% of patients treated with probenecid and 33% treated with placebo. The side effects encountered were mild in severity, reversible and represented extensions of the pharmacological activity of tienilic acid, hydrochlorothiazide and probenecid. These initial studies demonstrate that tienilic acid is safe and effective in the treatment of mild to moderate essential hypertension, salt and water retention states, including oedema associated with congestive cardiac failure or mild to moderate renal dysfunction, and in the management of elevated serum uric acid levels associated with gout.


The hypouricaemic effect of tienilic acid: experience in patients with hyperuricaemia.

The anti-hypertensive effect of 250 mg tienilic acid was comparable to that of 50 mg hydrochlorothiazide. Unlike hydrochlorothiazide, tienilic acid caused a statistically significant decrease in the serum uric acid values. Clinically non-significant rises in blood urea nitrogen and serum creatinine occurred with both diuretics. The hypouricaemic effect of tienilic acid given in a daily dose of 125 mg was significantly greater than that of 500 mg probenecid. Glucose tolerance in patients with mild maturity onset diabetes mellitus deteriorated with both tienilic acid and hydrochlorothiazide treatments with no statistically significant difference noted between the two treatments. Tienilic acid was well tolerated and no clinically significant haematological or biochemical abnormalities were noted.


Double-blind assessment of tienilic acid in essential hypertension.

The antihypertensive effectiveness of tienilic acid in doses of 250 mg once and twice daily was compared to hydrochlorothiazide 50 mg once and twice per day in a randomized double-blind trial lasting six weeks. Blood pressure fell significantly and to a similar extent with the larger dose of both drugs. This was accompanied by a slight decrease in body weight and serum potassium concentration and a slight increase in serum creatinine and blood urea nitrogen. The magnitude of these changes was similar with both drugs. Unlike hydrochlorothiazide, however, the administration of tienilic acid was associated with a marked drop in the concentration of serum uric acid. No disturbing side effects or evidence of serious toxicity were noted during treatment with the new drug.


Export without proteolytic processing of inner and outer membrane proteins encoded by F sex factor tra cistrons in Escherichia coli minicells.

Most tra proteins encoded by the Escherichia coli F sex factor are incorporated into the minicell envelope. We have now assigned the tra proteins to cytoplasm (TraIp and 2b), inner membrane (TraEp, TraMp, and TraSp), and outer membrane (6e, TraAp, TraBp, TraJp, TraKp, TraLp, and TraTp). two proteins, TraDp and 6d, were associated with both inner and outer membranes. The proteins exported to the inner or outer membranes did not undergo proteolytic cleavage (processing) whereas beta-lactamase was processed normally.


Gene 2 protein of bacteriophage T7: purification and requirement for packaging of T7 DNA in vitro.

The gene 2 protein of bacteriophage T7 is required for a late stage of T7 DNA replication because T7 gene 2 mutants fail to form normal concatemeric structures during the processing of newly synthesized T7 DNA. Extracts of gene 2 mutant phage-infected cells are unable to package T7 DNA into phage heads to form viable phage, as determined by an in vitro packaging assay for T7 DNA. Packaging activity can be stimulated greater than 100-fold in mutant extracts by the addition of extract prepared from cells infected with phage carrying a wild-type T7 gene 2, thus providing a complementation assay for the gene 2 protein. With this assay, the gene 2 protein has been purified to approximately 50% homogeneity. Purified preparations of the protein inhibit the activity of Escherichia coli RNA polymerase but have little effect on the activity of T7 RNA polymerase but have little effect on the activity of T7 RNA polymerase. The requirement for the gene 2 protein during T7 DNA replication may involve inactivation of E. coli RNA polymerase because the antibiotic rifampicin, a specific inhibitor of E. coli RNA polymerase, can substitute for the gene 2 protein in the in vitro packaging assay.


Quaternary structure of the ribosomal 30S subunit: model and its experimental testing.

In considering the structure of the 30S subunit of the Escherichia coli ribosome, we have assumed that: (i) all or almost all the proteins within the 30S particle are compact and globular, as recently shown for the isolated proteins S4, S7, S8, S15, and S16 in solution [Serdyuk, I.N., Zaccai, G. & Spirin, A.S. (1978) FEBS Lett. 94, 349-352]; (ii) the RNA within the 30S particle has approximately the same specific V-like or Y-like shape that was demonstrated for the isolated 16S RNA in a compact conformation [Vasiliev, V.D., Selivanova, O.M. & Koteliansky, V.E. (1978) FEBS Lett. 95, 273-276]. From these assumptions and using the numerous data reported on neighboring ribosomal proteins, we have constructed a model of the quaternary structure of the ribosomal 30S subunit. The model has been tested by calculation of the theoretical curves of neutron scattering at different contrasts, as well as those of x-ray scattering, and their comparison with the experimental scattering curves for E. coli 30S particles. It has been found that the calculated scattering curves for the model practically coincide with the experimental scattering curves for the 30S particles in the range of Bragg distances down to 40-55 A. The scattering curves calculated for several three-dimensional patterns of arrangement of the 30S subunit proteins proposed earlier have been shown to be inconsistent with the experiments.


Transposition of the Escherichia coli insertion element gamma generates a five-base-pair repeat.

We have determined DNA sequences surrounding the termini of the Escherichia coli insertion element gamma delta, both at its normal locus on the F (fertility) factor and at three different sites of insertion into the plasmid pBR322. After transposition, a five-base-pair pBR322 sequence is duplicated and appears in direct orientation adjacent to each end of the element. No such duplication flanks the ends of gamma delta in F, and there is no apparent homology between the sequences surrounding gamma delta in F and the five-base-pair duplications generated by insertion. These findings suggest that the duplications are not essential for transposition and that they do not act to direct gamma delta to a homologous site in the target chromosome. In addition, we find that the 35-base-pair inverted repeat that comprises the termini of gamma delta is strikingly similar in sequence to the ends of both the ampicillin-resistance transposon Tn3 and a 200-nucleotide-long sequence on the plasmid pSC101 which has been shown to mediate recombination with phage f1 replicative form. Within the terminal region, there is a specific heptanucleotide sequence common to each of the above elements and to bacteriophage Mu, all of which generate five-base-pair repeats upon insertion.


Monoclonal antibody to a plasma membrane antigen of neurons.

Fusion of spleen cells from a mouse immunized with chicken embryo retina cells with clonal mouse myeloma cells yielded a lymphocyte hybrid cell line that produced antibody that bound to neural tissue such as retina, brain, spinal cord, and dorsal root ganglia but not to other tissues tested. The antigen was shown by indirect immunofluorescence to be associated with plasma membranes of most, or all, neuron cell bodies in chicken retina, but little or no antigen was detected on axons or dendrites, Müller cells, or retina pigment cells. The activity of antigen A2B5 is relatively stable at 100 degrees C, is insensitive to trypsin, exhibits the solubility properties of a ganglioside, and is destroyed by neuraminidase. Antibody A2B5 cytotoxicity against retina cells is inhibited by a GQ ganglioside fraction from bovine brain (estimated half-maximal inhibition at 0.2 microM) or by N-acetylneuraminic acid (half-maximal inhibition at 5000 microM) but not by other purified gangliosides tested. These results suggest that the antigen is a complex ganglioside in plasma membranes of retina neuron cell bodies but not axons or dendrites.


leu operon of Salmonella typhimurium is controlled by an attenuation mechanism.

The nucleotide sequence of the control region of the leu operon of Salmonella typhimurium was determined. A prominent feature of this region is a signal for termination of transcription. In vitro, transcription does terminate at this site, yielding a leader RNA of about 160 nucleotides as a major product. This leader RNA is potentially translatable into a peptide containing 28 amino acids, 4 of which are adjacent leucine residues. Several regions of base complementarity exist within the leader, positioned such that pairing of one region precludes pairing of another. The position of the four leucine codons relative to two regions of base complementarity suggest a model for the regulation of the leu operon similar to that proposed by Yanofsky and coworkers for the trp operon. In addition, a third region of base complementarity was identified which, when incorporated into the model, explains why premature termination is the usual outcome when transcription is initiated in vitro by purified RNA polymerase.


Replacement of chromosome segments with altered DNA sequences constructed in vitro.

We have developed a method that may be of general application for the stable introduction of foreign sequences or deletions, constructed in vitro, into the chromosomes of Saccharomyces cerevisiae. No vector sequences are present in the final strains. Ability to transform cells with DNA, availability of a single selective marker, and integration of the transforming DNA by homologous recombination into the chromosomes are the requirements of the system. Any isolated gene can be deleted or altered and then be used to replace the wild-type chromosomal copy. An internal deletion mutant of the his3 gene and a transposition of a galactose-inducible region into chromosome XV have been generated by using the ura3 gene as the selective marker.


Cloning and nucleotide sequence of DNA coding for bovine preproparathyroid hormone.

We have cloned in Escherichia coli a DNA copy of mRNA coding for bovine preproparathyroid hormone. Double-stranded DNA was inserted into the Pst I site in plasmid pBR322 by using the poly(dG)-poly(dC) homopolymer extension technique to join the DNA molecules. Recombinant plasmids coding for preproparathyroid hormone were identified by the plasmid's ability to arrest specifically the translation of preproparathyroid hormone mRNA. The nucleotide sequence of the largest recombinant was determined by using both chemical and enzymatic techniques. The parathyroid insert contains 470 nucleotides--102 nucleotides from the 5' noncoding region of the mRNA, 345 nucleotides representing the entire coding region, and 23 nucleotides from the 3' noncoding region. The coding sequence clarifies the hormone's amino acid sequence, which has been disputed. Codon usage is discussed.


Primary structure of major outer membrane protein I of Escherichia coli B/r.

The amino acid sequence of the pore-forming outer membrane protein I (porin) from Escherichia coli B/r has been determined. The polypeptide contains 340 amino acid residues resulting in a molecular weight of 37,205. The transmembrane polypeptide has no stretches of nonpolar residues, uninterrupted by charged side chains, longer than 11 amino acid residues. Regarding polarity, the chain can be subdivided into three regions: a distinctly hydrophilic region between residues 1 and 82 (51.2% polarity), a fairly nonpolar region between residues 83 and 194 (33.9% polarity), and a more hydrophilic region up to the COOH terminus (48% polarity). These results are interpreted as evidence against a simple transmembrane structure in which the membrane is spanned by a single contiguous sequence of hydrophobic amino acids, as has been proposed, for example, for glycophorin.


Construction and selection of recombinant plasmids containing full-length complementary DNAs corresponding to rat insulins I and II.

We have used a synthetic deoxydecanucleotide to generate an insulin-specific cDNA probe suitable for selecting transformants that contain nearly full-length cDNAs corresponding to the mRNAs coding for rat insulins I and II. Double-stranded cDNA was synthesized from x-ray-induced rat insulinoma poly(A)-RNA, inserted in pBR322 plasmid DNA by the homopolymeric tailing technique, and cloned in Escherichia coli chi 1776. Colony hybridization with oligonucleotide-primed cDNA yielded 16 positive clones of which 7 corresponded to rat insulin I mRNA and 9 to rat insulin II mRNA. Restriction endonuclease maps of representative clones of each group indicated that these contained the complete coding sequences, as was confirmed by nucleotide sequence analysis of the 5' region of the cloned DNA for rat insulin II. Nucleotide sequence analysis also established the amino acid sequence of the prepeptide of rat preproinsulin II. Comparison of the amino acid sequence of the prepeptides of rat preproinsulin I and II shows that three conservative amino acid substitutions have occurred in this region of the molecule.


RNA polymerase III transcriptional units are interspersed among human non-alpha-globin genes.

Cloned human DNA fragments containing globin genes are transcribed in vitro to form discrete RNA species. One transcription unit is located approximately 1500 base pairs upstream from the G-gamma-globin gene. This transcript is partially homologous to a polymerase III template located approximately 1000 base pairs upstream from the delta-globin gene and to DNA located a short distance downstream from the beta-globin gene.


A 3.0-A resolution study of nucleotide complexes with aspartate carbamoyltransferase.

The binding sites of CTP, CDP, 5-BrCTP, and ATP to the allosteric site of aspartate carbamoyltransferase (carbamoylphosphate:L-aspartate carbamoyltransferase, EC 2.1.3.2) have been found in electron-density maps obtained at about 3 A resolution from x-ray diffraction studies of single crystals. The activator ATP binds in the anti conformation, whereas the inhibitor 5-BrCTP binds in the syn conformation. Both activator and inhibitor bind to the same local region of the enzyme. All of the cytidine nucleotides show important interactions of the base with the protein. The triphosphate conformations are similar, whereas the terminal phosphate of CDP occupies the site of the gamma-phosphate of CTP, thus implying a protein-nucleotide interaction at this site. These results are then related to biochemical studies.


Termination of transcription by bacteriophage T3 RNA polymerase: homogeneous 3'-terminal oligonucleotide sequence of in vitro T3 RNA polymerase transcripts.

RNA was synthesized in vitro from a T3 DNA template by T3 RNA polymerase and subsequently separated into seven discrete size classes (molecular weights ranging between 0.21 x 10(6) and 6.2 x 10(6)) by electrophoresis in polyacrylamide slab gels. RNase T1-generated 3'-terminal oligonucleotide fragments were then selectively isolated from either the unfractionated total RNA or the gel-purified specific transcripts by chromatography on columns of dihydroxyboryl-cellulose. Sequence analysis of these oligonucleotide products indicated that the unfractionated transcripts as well as all the individual major RNA species examined had a unique sequence, (Gp)UpUpUpUpUpGOH, at their 3' termini. The specificity of this sequence, as well as the total lack of any sequence heterogeneity at the ends of these transcripts, indicates a high degree of specificity of termination during transcription in this system.


Interference of nonsense mutations with eukaryotic messenger RNA stability.

The fine structure map of the yeast URA 3 gene was established by meiotic recombination, and amber nonsense mutations were located at different points on the map. The effect of the length of the labeling time on the specific radioactivity of ura 3 messenger RNA and on its repartition between poly(A)-RNA and RNA not containing poly(A) has been followed in nonsense mutants. Nonsense mutations reduce the messenger level without lowering its instantaneous rate of synthesis. The strength of the reduction depends on the position of the nonsense codon within the locus and concerns essentially the accumulation of polyadenylylated ura 3 mRNA.


A response of protein synthesis to temperature shift in the yeast Saccharomyces cerevisiae.

When Saccharomyces cerevisiae are subjected to a sudden increase in temperature (22 degrees C to 37 degrees C) they undergo extensive and, in some cases, extreme alterations in their rates of synthesizing individual polypeptides. These changes were monitored by pulse-labeling cells with [35S]methionine and separating the total soluble proteins by two-dimensional gel electrophoresis. Incorporation of 35S into individual proteins was measured by a computer-coupled autoradiogram-scanning method. The rates of synthesis of most proteins are transiently changed; 10-fold or greater induction or respression is common. This temperature response has also been studied in a mutant strain that is temperature sensitive for the nucleus-to-cytoplasm transport of RNA. In this mutant, not only the induction, but also a part of the repression in response to temperature upshift is largely inhibited. Conceivable mechanisms are discussed.


Nucleotide sequences of trpA of Salmonella typhimurium and Escherichia coli: an evolutionary comparison.

The complete nucleotide sequences of trpA of Salmonella typhimurium and Escherichia coli were determined. The nucleotide sequences are 24.8% divergent, compared with amino acid sequence divergence of 14.9%. Over half of the codons of each gene contain synonymous nucleotide changes. The pattern of synonymous nucleotide changes is consistent with the interpretation that such changes result from random mutational events. We do not find any evidence indicating that codon selection or RNA structure is of major selective value. We conclude that polypeptide function is the primary basis of selection in trpA and that most synonymous codon changes are selectively neutral.


Tetraethylthiuram disulfide (Antabuse) inhibits the human malaria parasite Plasmodium falciparum.

Plasmodium falciparum in culture grows optimally at 3% oxygen. Oxygen levels down to 0.5% still support growth, but anaerobic conditions do not. These findings, and the absence of the Krebs cycle in Plasmodium, suggested that in this organism oxygen may not function in electron transport but rather may act through metalloprotein oxygenases. Tetraethylthiuram disulfide (Antabuse, disulfiram) and its reduction product diethyldithiocarbamate inhibit many metalloprotein oxygenases and have a lipid/H2O partition coefficient and high binding constant for metal ions, favoring selective toxicity to the malaria parasite. These compounds exhibited active antimalarial effects in vitro in concentrations down to 0.1 microgram/ml, the lowest level tested. Tetraethylthiuram disulfide at a level as low as 1 microgram/ml inhibited parasite glycolysis with no effect on glycolysis of normal erythrocytes. Erythrocytes pretreated with this drug at 10 microgram/ml did not support growth of the parasite.


Comparison of cell-fusing activity of brain suspensions from patients with Creutzfeldt-Jakob disease and other degenerative neurological diseases.

In vitro cell-fusing activity of brain suspensions from 33 patients with transmissible cases of Creutzfeldt-Jakob disease (CJD) was compared to activity of brains from 26 patients with a variety of other degenerative neurological diseases, and with activity of brains from 25 patients without neurological disease. A significantly higher proportion of CJD brains (61%) was positive than other neurologically diseased brains (31-35%) or the brains without neurological disease (0-4%). Although not yet sufficiently specific to be useful as a diagnostic test for human CJD, the assay nevertheless opens a line of investigation into the pathophysiology of degenerative neurological diseases and could prove immediately useful in rapidly locating material of maximum interest in purification procedures for experimental spongiform encephalopathy virus.


Evidence for a cholinergic projection to neocortex from neurons in basal forebrain.

Unilateral stereotaxic injection of 3.5 nmol of kainic acid into the ventral globus pallidus of rats reduced biochemical cholinergic neuronal markers by 45-50% and virtually eliminated histochemical staining for acetylcholinesterase in neocortex ipsilateral to the lesion. At the lesion site, the large, multipolar neurons that stain densely for acetylcholinesterase were absent when compared with the uninjected side. Kainate was as effective as electrocoagulation for reducing cholinergic markers although it did not affect aminergic projections ascending through the lesioned area. The conclusion that the cholinergic projection originated in neuronal perikarya at the lesion site was supported by the failure of kainate or electrolytic lesions in contiguous regions to produce similar effects. These studies provide strong evidence for a cholinergic projection to neocortex from neurons in the forebrain in the nucleus basalis.


Differences in mutagenicity and cytotoxicity of (+)- and (-)-benzo[a]pyrene 4,5-oxide: a synergistic interaction of enantiomers.

In order to study the biological effects of (+)- and (-)-benzo[a]pyrene 4,5-oxide, a synthesis of these molecules has been developed based on the resolution of (+/-)-cis-4,5-dihydroxy-4,5-dihydrobenzo[a]pyrene. The (-) enantiomer of benzo[a]pyrene 4,5-oxide was 1.5- to 5.5-fold more mutagenic than the (+) enantiomer in strains TA 98, TA 100, TA 1537, and TA 1538 of Salmonella typhimurium and in Chinese hamster V79 cells. In studies with V79 Cells, the (-) enantiomer of benzo[a]pyrene 4,5-oxide was also more cytotoxic than the (+) enantiomer. When mixtures of the enantiomers were studied in V79 cells, synergistic cytotoxic and mutagenic responses were observed. The greatest cytotoxic and mutagenic effects occurred with a 3:1 mixture of the (-) and (+) enantiomers of benzo[a]pyrene 4,5-oxide, respectively.


Yeast chromatin is uniformly digested by DNase-I.

The DNase I (EC 3.1.21.1) sensitivity of transcribed yeast chromatin has been examined. We find that, in contrast to chromatin from higher eukaryotes, transcribed yeast chromatin and total yeast chromatin are equally sensitive to DNase I digestion. We interpret these results to mean that the entire yeast genome exists in a state that represents a restricted proportion of total chromatin in higher eukaryotes.


Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications.

A method has been devised for the electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets. The method results in quantitative transfer of ribosomal proteins from gels containing urea. For sodium dodecyl sulfate gels, the original band pattern was obtained with no loss of resolution, but the transfer was not quantitative. The method allows detection of proteins by autoradiography and is simpler than conventional procedures. The immobilized proteins were detectable by immunological procedures. All additional binding capacity on the nitrocellulose was blocked with excess protein; then a specific antibody was bound and, finally, a second antibody directed against the first antibody. The second antibody was either radioactively labeled or conjugated to fluorescein or to peroxidase. The specific protein was then detected by either autoradiography, under UV light, or by the peroxidase reaction product, respectively. In the latter case, as little as 100 pg of protein was clearly detectable. It is anticipated that the procedure will be applicable to analysis of a wide variety of proteins with specific reactions or ligands.


Energy-dependent processing of cytoplasmically made precursors to mitochondrial proteins.

Earlier work has shown that mitochondrial proteins synthesized in the cytosol are initially made as larger precursors which are then transferred into the organelles and processed to their mature size in the absence of protein synthesis. It is now demonstrated that depletion of the mitochondrial matrix ATP in intact yeast spheroplasts by various combinations of inhibitors and mutations prevents the processing of precursors to the three largest subunits of the mitochondrial F1-ATPase and two subunits of the cytochrome bc1 complex. These polypeptides are all synthesized outside the mitochondria and transported to the mitochondrial matrix or inserted into the mitochondrial inner membrane. In contrast, depletion of the matrix ATP does not inhibit processing of the precursor to cytochrome c peroxidase; this enzyme is located in the mitochondrial intermembrane space which is freely accessible to ATP made in the cytosol. The processing of extramitochondrially made precursors or the transfer of these precursors across the mitochondrial inner membrane is thus dependent on ATP.


Subunit structure of dihydrolipoyl transacetylase component of pyruvate dehydrogenase complex from Escherichia coli.

Limited tryptic digestion of the pyruvate dehydrogenase complex of Escherichia coli or its dihydrolipoyl transacetylase core cleaves the trypsin-sensitive transacetylase subunits into two large fragments, A (lipoyl domain) and D (subunit binding domain). Release of fragments A from the complex does not significantly affect its sedimentation coefficient or its appearance in the electron microscope. Fragment A contains the lipoyl moieties ((3)H-labeled), is acidic with an apparent isoelectric point of about 4.0, has a M(r) of 31,600 as determined by sedimentation equilibrium analysis, and has a swollen or extended structure (f/f(o) = 1.78). Fragment A exhibits anomalous properties, probably due to its acidic nature. It is resistant to staining with Coomassie blue and it migrates on sodium dodecyl sulfate/polyacrylamide gels as if it had a M(r) of 46,000-48,000. Further tryptic digestion converts fragment A into a lipoyl-containing fragment of M(r) 20,000 (fragment B) and eventually into an apparently stable product of estimated M(r) about 10,000 (fragment C). Fragment D has a compact structure of M(r) about 29,600 as determined by sedimentation equilibrium analysis in 6 M guanidinium chloride, and it possesses the intersubunit binding sites of the transacetylase, the binding sites for pyruvate dehydrogenase and dihydrolipoyl dehydrogenase, and the catalytic site for transacetylation. The assemblage of fragments D is responsible for the cube-like appearance of the transacetylase in the electron microscope. High-resolution electron micrographs of the transacetylase show fiber-like extensions, apparently corresponding to tryptic fragment A, surrounding the cube-like core.


Accessibility of guanine at position 44 in the invariant sequence 5'CCG44AAC3' of Escherichia coli 5S RNA to reaction with kethoxal.

The reaction of Escherichia coli ribosomes with beta-ethoxy-alpha-ketobutyraldehyde (kethoxal) in a buffer containing 50--100 mM Tris.HCl at pH 7.4, 50 mM NH4Cl, and 5 mM Mg(OAc)2 readily released the 5S RNA from the ribosomes. When liberated, the 5S RNA is in a conformation such that position 44 is selectively reactive, in addition to the normally reactive quanines at positions 41 and 13. Positions 41 and 13 have been previously shown to react in the 5S RNA in situ. The resulting new RNase T1 resistant oligonucleotides 5'CCG 44K AAUCAG51(3') and 5'ACCCCAUG 41KCCG 44KAACUCAG51(3') have been isolated and identified. These oligonucleotides have not been found in RNase T1 digests of 5S RNA that is not released from the ribosome. The guanine at position 44 is part of the invariant sequence 5'CCG44AAC3' which includes that portion of the molecule thought to interact with the invariant 5'GT psi C3' of tRNAs in the ribosomal A site. This invariant sequence of the 5S RNA may also form part of the binding site for protein L5.


On the evolution of accuracy and cost of proofreading tRNA aminoacylation.

Aminoacylation of tRNA occurs with a high degree of accuracy in many cases because misacylated molecules are effectively proofread on the aminoacyl-tRNA synthetase by preferential hydrolysis. This hydrolysis releases an ATP equivalent of energy. An explicit relationship between cost of proofreading and the resulting degree of accuracy is presented. Experimental data from Escherichia coli for isoleucyl-tRNA synthetase proofreading valyl-tRNAIle are examined by means of this relationship, and a conjecture concerning the natural selection of accuracy and proofreading costs is put forth and tested. We have found the energy cost of accurate proofreading to be high. The minimum error, derived in previous theoretical studies, is never actually reached. Instead, higher values, determined by the balance between energy wasted in the cell as a consequence of error and the energy cost of proofreading, appear to be selected. The total cost of proofreading all types of tRNA aminoacylations is estimated to be approximately 2% of the energy required to synthesize a bacterial cell.


Genetics of type II glycogenosis: assignment of the human gene for acid alpha-glucosidase to chromosome 17.

We have studied somatic cell hybrids between thymidine kinase (EC 2.7.1.75) deficient mouse cells and human diploid fibroblasts for the expression of human acid alpha-glucosidase (EC 3.2.1.20). A deficiency in this enzyme is associated with the type II glycogenosis or Pompe disease. All 30 somatic cell hybrids selected in hypoxanthine/aminopterin/thymidine medium expressed human acid alpha-glucosidase and galactokinase (EC 2.7.1.6) and retained human chromosome 17; counterselection of the same hybrids in medium containing 5-bromodeoxyuridine resulted in the growth of hybrids that concordantly lost the expression of human acid alpha-glucosidase and galactokinase as well as human chromosome 17. Hybrids between thymidine kinase-deficient mouse cells and fibroblasts from a patient with Pompe disease that contained human chromosome 17 were found not to express human acid alpha-glucosidase. Because we have already shown that hybrids between mouse peritoneal macrophages and GM54VA simian virus 40-transformed human cells selectively retain human chromosome 17 and lose all other human chromosomes, we tested 13 independent mouse macrophage x GM54VA hybrid clones, including two that retained human chromosome 17 and no other human chromosomes, for the expression of human acid alpha-glucosidase and galactokinase. All 13 hybrid clones were found to express these human enzymes. Thus, we conclude that the gene coding for human acid alpha-glucosidase is located on human chromosome 17.


Activation of mating type genes by transposition in Saccharomyces cerevisiae.

Yeast Saccharomyces cerevisiae may express an a or alpha mating type. These cells types may be interconverted as a consequence of heritable genetic alteractions at the mating type locus (MAT). According to the more general controlling element model [Oshima, U. & Takano, I. (1971) Genetics 67, 327--335] and the specific cassette model [Hicks, J., Strathern, J. & Herskowitz, I. (1977) in DNA Insertion Elements, Plasmids and Episomes, eds. Bukhari, A. I., Shapiro, J.A. & Adhya, S. L.(Cold Spring Harbor Laboratory, Cold Spring Harbor, NY), pp. 457--462], the regulatory information required for switching the MAT locus exists at two other loosely linked loci, HMa and HMalpha. Specifically, the HMa and HMalpha loci are proposed to carry silent alpha and silent a genes, respectively. According to these models, switching occurs when a replica of a silent gene replaces the resident information at the mating type locus and is thereby expressed. These models predict that mutations at the silent ("storage") loci would generate defective MAT loci subsequent to the switching process. Therefore, the behavior of HMalpha mutants during the mating type interconversion was investigated. The results demonstrate that defective MATa alleles are generated by switching the MATalpha locus in HMalpha mutants. Thus, the genetic information from HMalpha is transposed to the mating type locus. These results provide genetic evidence in support of these models.


Evidence that a single DNA ligase is involved in replication and recombination in yeast.

The possible existence in yeast of different nuclear DNA ligase enzymes led us to ask whether induced recombination (gene conversion) involves the same ligase as that involved in DNA replication. The conditional cdc9 mutant is known to be defective, under restrictive conditions, in the rejoining of Okazaki fragments. We show here that under the same conditions, x-ray-induced convertants within the cdc9 locus are produced with kinetics indicating that most, if not all, of the conversion events require the participation of the cdc9-controlled ligase. Thus, the same DNA ligase is involved in DNA replication and in induced gene conversion.


Enhanced mitotic recombination in a ligase-defective mutant of the yeast Saccharomyces cerevisiae.

The temperature-sensitive Saccharomyces cerevisiae cell cycle mutant cdc9 is defective in DNA ligase, and the DNA synthesized at the restrictive temperature contains many single-strand breaks. We find that holding a diploid homozygous for cdc9 at the restrictive temperature and then plating cells at the permissive temperature gives rise to increased intragenic and intergenic recombination. In the latter case, recombinants signaled by the ade2 locus rise to about 4% of the survivors after 6 hr of incubation at the restrictive temperature. We propose that the single-strand breaks left in DNA synthesized at the restrictive temperature may lead to recombination.


Characterization of a protein correlated with the production of knob-like protrusions on membranes of erythrocytes infected with Plasmodium falciparum.

Membranes of erythrocytes infected with Plasmodium falciparum develop protrusions called "knobs." These protrusions are not apparent on erythrocytes infected with young parasites (rings) but develop with the growth of parasites to the trophozoite and schizont stages. The nature and origin of knobs were characterized by comparing the stage-specific proteins of two culture lines of P. falciparum, K+ and K-. K+ parasites produce knobs; K- parasites do not. Erythrocytes infected with both types of parasites were labeled metabolically and samples were analyzed by electrophoresis in sodium dodecyl sulfate/polyacrylamide gels. There were no apparent differences in Coomassie blue-stained or radioactive components of rings of K+ and K- parasites. However, erythrocytes infected with K+ trophozoites or schizonts showed a major labeled protein, with an apparent molecular weight of approximately 80,000, that was not present in any developmental stage of K- parasites or in K+ rings. A fraction enriched in membranes from erythrocytes infected with K+ trophozoites showed enrichment of this protein. The results indicate that this protein, synthesized by the parasites, is correlated with the formation of knobs on the host cell membrane. Two additional labeled components were identified. These appeared with the development of schizonts in both K+ and K- parasites and are therefore stage-dependent and not correlated with knobs.


Application of LAL for detection of endotoxin in antibiotic preparations.

The Limulus amebocyte lysate (LAL) test has been investigated as an alternative method to the USP pyrogen test for the detection of endotoxin contamination in these antibiotic preparations: clindamycin phosphate, lincomycin hydrochloride, neomycin sulfate, and spectinomycin hydrochloride. The antibiotic preparations were tested at the maximum concentrations that would not inhibit gelation of LAL. The USP pyrogen test was also performed for comparison. The LAL and the USP pyrogen tests correlated extremely well when an acceptance criterion based on the minimum pyrogenic dose (MPD) of endotoxin per human dose of drug was used for the LAL test. Use of this MPD provides a practical and feasible acceptance creiterion for the LAL test and assures that the LAL sensitivity approximates or surpasses that of the USP pyrogen test.


An easily mass produced cannula system for chemical stimulation of the brain.

This paper describes a cannula system for chemical stimulation of the brain which can be easily mass produced in a reliable and inexpensive manner.


[Aspects of the application of models in pharmaceutical research (author's transl)].

Starting from historical examples of the application of models in scientific research, the author treats the present significance of this working method in pharmacy. A short description of various types of models and of the definition of the term "model" is followed by an outline of the major aspects to be considered in using models. The different steps of model elaboration, the requirements to be considered with model elaboration as well as questions concerning the analogy, main properties, goals and limitations of models, and the validity of the results obtained are briefly dealt with and illustrated by examples.


Further experiences with the pectoralis major myocutaneous flap for the immediate repair of defects from excisions of head and neck cancers.

In our experience with 14 pectoralis major myocutaneous flaps they have been very reliable for reconstructions in a variety of clinical situations--especially in the repair of defects from extensive cancer resections in the head and neck area, including orbital exenterations. The flaps can be transferred immediately, without a delay.


Preferential use of end-to-side arterial anastomoses in free flap transfers.

In our early clinical experience with free flaps, we used end-to-end arterial anastomoses and in 9 our of 24 we had complete failures--7 of which were due to early arterial thrombosis. Contrarily, in 41 consecutive free flaps with end-to-side anastomoses we have not had a single failure. At the same time that we began using the end-to-side anastomoses, we also began using the latissimus dorsi free flap as our flap of first choice, and we agree that this was probably an additional reason for our improved success rate. The use of end-to-side anastomoses has the following advantages: (1) a high success rate; (2) preservation of all existing vessels in an injured extremity; (3) greater freedom of operative planning; and (4) technical simplicity in terms of access to the vessels. For us, these advantages have made end-to-side anastomosis the technique of choice in the transfer of free flaps.


Management of pressure sores in a specialty center. A reappraisal.

We report a study on the surgical management of 145 pressure sores in 115 patients treated in a spinal cord injury center. There is a definite trend toward better education of these patients, who do not develop their first pressure sores until years following the injury. When the patient comes in for an ulcer, he is usually healthy and the ulcer is small and clean. In such instances the ulcer can be excised and closed, preferably with a myocutaneous flap, and the patient can usually begin sitting by the 21st post-operative day. In the ideal setting he may be discharged to his home on a custom-fitted (for pressure) cushion within 4 to 5 weeks, without increasing the risk of recurrence. Prophylaxis for the future is, probably, the most essential part of the treatment.


Two replantations of severed ear parts.

Two successful cases of replantation of part of an ear are presented; both were done by simple suture. The larger of these replants consisted of a 13 x 43 mm segment of the superior helix and concha. Both were vascularized beofre 48 hours. The greatest problem was venous congestion. In the larger replant we made multiple puncture wounds daily on both sides of the graft with an 18-gauge needle to help relieve this.


Anger and its control in Graeco-Roman and modern psychology.

Modern psychologists have studied the phenomena of anger and hostility with diverse methodologies and from a variety of theoretical orientations. The close relationships between anger and aggression, psychosomatic disorder and personal unhappiness, make the understanding and control of anger an important individual and social goal. For all of its sophistication and accomplishment, however, most of the modern research demonstrates, to its disadvantage, a lack of historical perspective with respect to the analysis and treatment of anger, whether normal or pathological. This attitude has deprived psychology of a rich source of empirical observations, intriguing, testable hypotheses, and ingenious techniques of treatment. Of the literature that has been neglected, the analyses of the emotion of anger in the writings of Greek and Roman moral philosophers, particularly Aristotle (4th century B.C.), Seneca (1st century A.D.) and Plutarch (early 2nd century A.D.) are of particular interest. Although modern analyses and methods of treatment are in some ways more refined and more quantitatively precise, and are often subjected to validation and modification by empirical-experimental tests, scientific psychology has, to date, contributed relatively little to the understanding and control of anger that is novel except for research on its physiological dimensions. We can still benefit from the insight, prescriptions and procedures of the classicists, who in some respects offer more powerful methods of control than the most recently published works. Naturally, the modern psychotherapist or behavior therapist can and must go beyond the ancients, as is inherent in all scientific and intellectual progress, but there are no scientific or rational grounds for ignoring them as has been done for 75 years.