[Prognosis and current treatment of dermatomyositis].

The present revision has been carried out in order to final out to what extent corticosteroids have improved the vital and functional prognosis of dermatomyositis. Over the sixties and in the early seventies, statistical tables have not shown any substantial differences compared with those of the pre-steroid era. It has been observed since 1973 that early treatment with high doses (1-2 mg of prednisone per kg per day) clearly improves the vital prognosis of infantile dermatomyositis, but not the functional one. In adults, there is less experience and the problem always exists of a possible underlying neoplasm. In cases with resistance to corticosteroids, the association of immunosuppressors, particulary methotrexate, has begun to be tested. There is no proved effective treatment of calcinosis which results in functional recovery.


[Immunotherapy of warts. Is it an experimental model for cancer immunotherapy?].

The warts produced by virus Papova, provedly cancerous, have immunological characteristics that allow to establish some analogies with cancer. Its immunotherapy is studied with levamisole and by means of a delayed immunity reaction "in situ" with regulated intensity. The level of delayed immunity in the patient with warts is established by quantitative DNCB test, finding that the same is impaired in 60% of men and 87% of women. The levamisol therapy cures 54% of warts. The patients that not cure but improve their delayed immunity level after the treatment with levamisol, are submitted to external application of DNCB, using a concentration calculated on the quantitative test results. With regard to their delayed immunity we introduce a new group of patients: the hiperergic type or reactive to 2,5 microgram of DNCB that cures their warts by the sole action of the test. Once obtained the curve of the distribution of delayed immunity values in the warts population before and after the levamisole therapy, we observe that the first is identical to that of cancer patients. In view of the tight relation among diseases with impaired delayed immunity, such as warts, herpes, aphtas, piodermitis and cancer (residual or postsurgical), we propose the same management, control and immunotherapy for all of them.


[Immunology of bullous diseases-II. Cicatricial pemphigoid. Herpes gestationis and dermatitis herpetiformis].

The immunological aspects of cicatricial pemphigoid, herpes gestationis and dermatitis herpetiformis are reviewed in this article. The immunofluorescence findings in these diseases are emphasised. The possible implication of the complement system in the pathogonesis of these bullous diseases, as well as the present knowledge about the sequence of actuation of the alternate pathway components are discussed.


[Lipid composition of cutaneous lesions in different types of xanthomatosis].

Twenty one specimens of cutaneous xanthomas from different types of hyperlipoproteinaemic and normolipidemic xanthomatosis were obtained and analyzed by thin layer chromatography. After separation and development, the areas were determinated by densitometry, and the results are given in percentages for each development. Acording to the results, the following data are of interest: -- Recents xanthomas have greater amount of lipids. -- Cholesterol esters (EC) are prevalent in xanthomas and in normal skin the triglycerides fraction. -- Monoenoic esters (EM) are prevalent on EC chromatography, like in normal skin. -- Finally, there are not significant variations between lipid composition of xanthomas in the different Xanthomatosis.


[Treatment of psoriasis with a derivative of retinoic acid by oral route].

In the study presented, an evaluation has been made of the results achieved in a group of 32 psoriatic patients treated with a derivative of the retinoid acid, i.e. Ro 10-9359, taken orally. The therapy used was considered highly favourable in 28 cases and favourable in 3. It is considered that the treatment is effective independently of the time of evolution and of the extension of seriousness of the disease with no effects on the visceral or humoral sectors. All the information included in the present study allows to assert that the treatment of psoriasis with this derivative of the retinoid acid represents a significant progress as compared with the corticoids or cythostatics therapy.


[Alcoholism and skin].

In this study we are reviewing the pathology of alcohol and commenting on those dermatological processes most closely related to chronic alcoholism. We adopted the definition of alcoholism as outlined by the WHO (World Health Organization). Also, a general brief description of the woelwide history of alcoholism was included, focusing specially on Argentina with its corresponding legislative study and statistics.


[A new method of endonasal postoperative care (author's transl)].

Aerosol therapy was tested in 27 patients postoperatively instead of nasal packing. The advantage of early ventilation and drainage prevents secondary infections. The constant decongestion embolishes band-formation.


[Cholestasis after renal transplantation and immune-suppressive therapy (author's transl)].

A 39 year old female patient developed jaundice 16 months after having received a renal transplant. Intrahepatic cholestasis was diagnosed on the basis of serum enzyme concentration patterns and of histology of a liver biopsy specimen; it was thought to be due to immune-suppressive therapy. Azathioprine was stopped and the hepatic situation normalized within 5 months. HBs-infection was present at the same time, so it is being discussed, if this condition may have influenced the development of intrahepatic cholestasis as well. It has to concluded from this case report, that liver function of patients with renal transplants receiving azathioprine has to be controlled regularly. Stopping azathioprine may induce normalization of even severely damaged liver function without influencing the function of the renal transplant.


[Mathematical bases for automated automated equipment for mass medical screening and diagnosis].

Mathematical methods and the programmes for the computer choice of informative diagnostic signs and constructing resolving rules to formulate groups of risk for certain affections in automating large-scale medical examinations are described. The use of a method for linear discriminant functions is shown. The applicability of the programme on examples of early identification of mammary cancer and rheumatic affections is demonstrated.


Infectious complications of human bone marrow transplantation.

Infections are an almost inevitable complication of human bone marrow transplantation and account for the majority of deaths in transplant recipients. Even prior to the initiation of the transplantation procedure, patients may present with infections complicating previously unsuccessful chemotherapy for hematological malignancy or aplastic anemia. Nevertheless, these pre-transplantation infections should not exclude the possibility of bone marrow transplantation if they can be successfully controlled with specific antimicrobial therapy and necessary adjunctive measures. The immediate post-transplantation period prior to engraftment is characterized by severe marrow aplasia that results from high-dose chemotherapy and total-body irradiation. Infections are primarily septicemias and localized processes caused by bacteria and fungi and their incidence increases as the intensity of immunosuppression is escalated. The high mortality associated with bacterial septicemia makes early, empirical antibacterial therapy mandatory. However, the reduction in mortality from bacterial infection resulting from such an aggressive approach may be offset by a higher mortality from invasive fungal infection, especially in patients with prior fungal colonization and undergoing prolonged conditioning therapy. Thus, until more specific and sensitive tests for the diagnosis of invasive fungal infection become available, empirical intravenous amphotericin should be considered in patients who are persistently febrile and deteriorate clinically in the face of appropriate antibacterial therapy. Interstitial pneumonia associated with severe GVHD is the major infectious complication after successful marrow engraftment and is the most significant barrier to long-term survival. Trimethoprim-sulfamethoxazole is effective prophylaxis against interstitial pneumonia due to Pneumocystis carinii, but one half of the patients still develop a pneumonitis either associated with CMV or of unknown etiology. Mortality from interstitial pneumonia is related to prior radiation therapy while survival is associated with a four-fold rise in CMV CF antibody titer. The latter observation supports the need to investigate passive immunization with CMV antibody as a means of preventing some interstitial pneumonias. Despite the progress made in many areas of human bone marrow transplantation, the majority of graft recipients still die of infectious complications. Thus, new approaches to the management of infections in transplant recipients are urgently needed. Better-tolerated oral nonabsorbable antibiotics, laminar-air-flow rooms, granulocyte transfusions, and chemotherapy and immunotherapy for CMV are among the prophylactic and therapeutic measures that must be critically evaluated in well-controlled, prospective studies. Continued assessment of the infectious complications of bone marrow transplantation is a critical aspect of any ongoing transplant program, not just a research goal...


The clinical features of hepatic angiosarcoma: a report of four cases and a review of the English literature.

Four cases of hepatic angiosarcoma are reported with a review of 99 other cases in the English literature. Angiosarcoma of the liver is associated with chronic exposure to thorotrast, vinyl chloride, arsenicals, radium and possibly copper and with chronic idiopathic hemochromatosis. Although 40% of patients have hepatic fibrosis or cirrhosis at autopsy, the nature of the association between chronic liver disease and hepatic angiosarcoma is unknown. The clinical presentation of hepatic angiosarcoma is nonspecific with abdominal pain, weakness and weight loss common complaints and with hepatomegaly, ascites and jaundice common findings. Liver function tests are usually abnormal but there is no one liver function test or set of tests specific for the tumor. The occurrence of thrombocytopenia and disseminated intravascular coagulation is characteristic of hepatic angiosarcoma and may be related to local consumption of clotting factors and formed blood elements in the tumor. Catastrophic intraabdominal bleeding is also characteristic and occurs in one-fourth of all cases. This complication is likely related to the high incidence of clotting abnormalities and the vascular nature of the neoplasm. Selective hepatic arteriogram and open liver biopsy are the foundations of diagnostic evaluation. Percutaneous liver biopsy should be avoided. Failure to appreciate the possibility of hepatic angiosarcoma in the proper clinical setting, leading to blind percutaneous biopsy, may result in failure to make the diagnosis at the cost of significant morbidity and mortality. Survival of patients with hepatic angiosarcoma is brief; only 3% live longer than 2 years. Treatment of the tumor to date is empirical. There are probably a few patients who might benefit from radical surgery with curative intent. For all others chemotherapy is indicated. Adriamycin is active against hepatic angiosarcoma, but optimal dose and mode of administration require further investigation. Further study is also required to delineate the cause of hepatic angiosarcoma in the 60% of cases without definite epidemiologic association.


Syngeneic transplantation of the fetal rat pancreas IV. Dissociated versus whole organ implantation.

Reversal of insulinopenia, hyperglycemia, glycosuria, and polyuria associated with severe alloxan diabetes in the rat was accomplished by syngeneic transplantation of whole late-gestation fetal rat pancreata. Intravenous glucose tolerance test (GTT) revealed an improved yet still abnormal glucose and insulin response in reversed recipients reconstituted with as few as two pancreata from fetal donors. Eight fetal donors were sufficient to return glucose and insulin response following GTT to normal. Seventy to eighty percent fewer donors were required when the pancreata were transplanted in their entirely as opposed to transplantation of pancreata subjected to prior enzymatic and mechanical dissociation. The facility and simplicity of the whole fetal pancreas implantation technique makes it an appealing model for further study of islet growth and differentiation at the transplant site and of its effect on the metabolic state of the recipient.


The unpolymerised form of actin in non-muscle cells.

Several lines of evidence point to the existence of unpolymerised actin in non-muscle cells. Ultrastructural examination reveals both a variety of actin filament bundles and actin in a controversial organisational state. Arguments are cited that this material, which at least in part is found close to the plasma membrane, represents unpolymerised actin rather than a random array of single actin filaments. The rearrangement of actin filament bundles during the cell cycle, and in response to experimental manipulation, suggests a turnover of filaments by a polymerisation-depolymerisation cycle. Extracts made from non-muscle cells under conditions where muscle actin would polymerise still contain appreciable fractions of monomeric actin. Studies on purified polymerisation-resistant actin from a variety of sources reveal the presence of a small protein which binds specifically to actin and prevents polymerisation. In the last section of the article, we expand the idea that this auxiliary protein is a central control element in the regulated exchange between non-polymerised and polymerised actin in vivo.


The cytoskeleton and cytomusculature in embryogenesis--an overview.

The role of microfilaments and microtubules comprising the cytoskeleton and cytomusculature in embryonic development is discussed. The cytomusculature, as microfilaments, is evident in both the unfertilized and fertilized egg and probably plays a role in sperm incorporation, cortical contractions, and cytokinesis. The cytoskeleton, in the form of microtubules, appears after fertilization in the form of the sperm aster and the mitotic apparatus. The cytoskeleton and cytomusculature play a decisive role in shape changes of individual cells responsible for gastrulation, neurulation, and morphogenesis of other epithelial sheets. Several developmental defects, such as spina bifida, may be related to malfunctioning of the cytoskeleton or cytomusculature. The putative role of microfilaments and microtubules in cell shape changes during embryogenesis can best be, at least initially, inferred from careful ultrastructural observations.


The cytoskeleton and plasma membrane.

The major cytoskeletal elements (microfilaments, microtubules, and 10-nm filaments) are frequently found attached to or near the plasma membrane in arrays which can sometimes be shown experimentally to be related to cell form and movement. Ultrastructural investigations show that attachment is direct, by amorphous electron-dense material, by cell-cell junctions, or by cell-substrate attachment sites, but the chemistry of attachment is poorly understood. The structural and functional polarity of the attached elements has been defined for some microfilaments attached to plasma membrane, but this important parameter has been investigated only slightly for microtubules and not at all for 10-nm filaments attached to membranes. Assemblies of cytoskeletal elements and plasma membrane evidently are structurally stable enough to be observable by electron microscopy and to survive isolation by the usual biochemical techniques, but observations of living cells show that many assemblies of cytoskeleton and plasma membrane undergo rearrangement and interconversion. The biochemical basis and physiological meaning of many of these changes are poorly understood.


The role of the cytoskeleton in pancreatic B-cell function.

The ultrastructural organization of B-cell microtubular-microfilamentous system, its alteration by several pharmacological agents and the concomitant changes in the dynamics of insulin release, the biochemical characterization of islet tubulin and actin, the involvement of microtubules in the process of proinsulin biosynthesis and conversion, the analysis of motile events in endocrine pancreatic cells, the possible participation of microtubular-microfilamentous structures in cell surface organization of the B-cell, and the anomaly of the microtubular apparatus in certain pathological conditions are reviewed. The experimental data support the view that microtubules and microfilaments play an essential role in the process of insulin synthesis and release, as well as in the mechanism of glucagon secretion.


The role of cytoskeleton in adreno-medullary secretion.

Chromaffin cells of the adrenal medulla contain prominent arrays of microtubules and microfilaments. One population of microtubules radiates from the cytocentrum and permeates the areas of the cytoplasm containing chromaffin granules; the other population of microtubules forms a subplasmalemmal network together with actin-like microfilaments. Hence, the cytoskeletal elements in chromaffin cells are strategically located to participate in the mobility of chromaffin granules to the cell surface and to regulate access of the granules to the plasma membrane during exocytosis. Agents which effect the integrity of the cytoskeleton clearly affect the secretory process in a manner which indicates that the microtubules and microfilaments play an active role in the release process.


Distribution and function of cytoskeletal proteins in lung cells with particular reference to 'contractile interstitial cells'.

Cytoskeletal proteins are demonstrated in the interstitial cells of the lungs. These proteins appear in the cytoplasm as bundles of microfilaments, the individual filaments measuring 40--80 A in diameter. The presence of actin and myosin in these cells is demonstrated by immunofluorescence. Antiactin antibodies (AAA) obtained from patients with chronic aggressive hepatitis, as well as AAA and antimyosin antibodies prepared in the rabbit, are used. The major difference between the cytoskeletal proteins of interstitial cells and other cells of the alveolar tissue (type II epithelium, pericytes, and near the junctional complexes of endothelial cells) is that the microfilaments within the interstitial cells are organized into bundles forming tiny intracytoplasmic 'muscles'. Furthermore, they appear to be much more abundant and seem to anchor the cell on the alveolar basement membrane by hemidesmosome-like structures. These peculiar cytological features provide these cells with an important functional capacity. Being located in the 'pillars' which cross the capillary space, the contraction of interstitial cells may modify the alveolocapillary configuration in some circumstances. The physiological importance of such an 'active' alveolar motility is to provide the lung with a mechanism of autoregulation of the ventilation/perfusion (V/Q) ratio at alveolar level.


The cytoskeleton in cultured cells: coordinate in vitro regulation of cell growth and shape.

Adenopolyposis of the colon and rectum (ACR) links the well-characterized phenomena of murine oncogenic virus transformation with the progression of a human cancer. The same syndrome links defects in fibroblast growth control and cytoskeletal organization to a tumor of epithelial origin. Since skin fibroblasts are involved in this colonic tumor, the syndrome is very likely to be systemic. That is, one element of normal growth regulation of epithelial cells in situ may be provided by the fibroblasts residing beneath their basement membrane. These observations have led to a novel approach to early detection of persons at risk for a tumor, via the behavior of their skin fibroblasts in culture. At present, it is rarely possible to detect persons at risk for malignancy before the appearance of a frank invasive or metastatic growth. Although many biochemical assays have been proposed as indicators of pre-malignant states or cryptic early tumors, most have eventually been shown to be related to age, sex drug treatment, or other variables linked to but not clearly indicative of, a malignancy. Two serious problems limiting attempts to detect preneoplastic states or a disposition to eventual neoplasia are the inherent low frequency of incidence of any single type of tumor and the difficulty of obtaining identical sample material from prospective or actual patients once they are located. Our approach to these problems significantly departs from the common dependence upon isolation of cells from the site of a tumor. Clearly, it is an easier task to scan skin fibroblasts for disrupted cytoskeletal patterns than it is to obtain epithelia cells from most tissues at high risk for malignancy. This line of work, buttressed by information derived from the model system of SV40 transformation, may provide a novel mode of early detection of other human malignancies, as it has for ACR.


The cytoskeleton in cancer cells in animals and humans.

Immunofluorescent staining of human cancer cells with antibodies against actin and myosin shows an important increase of brightness when compared with staining of normal cells from control tissues. Electron microscopic examination of cancer cells shows accumulation of cytoplasmic microfilaments (40--80 A in diameter) with some larger filaments (100--120 A in diameter) scattered in between compared to normal cells from control tissues. Such filaments are particularly abundant at the cell periphery. These findings indicate that the cytoplasmic contractile apparatus of cancer cells is more developed than that of normal cells. Such development may at least in part explain the invasive activity of malignant cells.


Contractile proteins as autoantigens.

Smooth muscle antoantibodies are found in high titre in some patients with chronic active hepatitis, and in lower titres in a number of other liver diseases and certain viral infections. They are directed at contractile proteins of the actomyosin group, and anti-actin activity appears to predominate. Whether occurring in disease affecting the liver or in other conditions, smooth muscle antibody production is thought to be stimulated when contractile proteins of non-muscle cells become immunogenic as a result of changes induced in the cells by viral infection or by other unknown causes of derangement of cytoskeletal structure.


The contractile system of blood platelets and its function.

The various manifestations of platelet activation are derived from a reorganization of components of the contractile and microtubular systems. The controversial initial stages of excitation-contraction coupling in platelets lead to the release of calcium from the dense tubular system, the morphological counterpart of the muscle sarcotubular closed vesicles. Calcium triggers the actin-myosin interaction and the developing force, possibly together with a local increase of the cation concentration, may cause the collapse of the microtubular ring and its reappearance in the forming long pseudopodia. Actin-myosin interaction is modulated by several factors among which tropomyosin-troponin, responsible for the calcium-sensitivity of contractile processes, and phosphorylation of one of the myosin light chains. Platelet actin is anchored to the membrane and its sliding towards the short myosin filaments may form the basis for platelet shape change. Platelet alpha-actinin and actin-binding protein are able to aggregate actin into an impressive gel. Therefore, the contractile proteins seem to have a double role in controlling the consistency of the cytoplasmic gel on the one hand, and the contractile manifestations related to motility on the other hand. One of the most important features of the 'contracted' platelet is the rigidity of the pseudopodia brought about by the 'gelification' of actin filaments and the presence of microtubules. A new model for clot contraction is proposed, based on the rigidity of the long spiky pseudopodia and on the motile properties of platelets. While migrating towards each other, the interlocking pseudopodia from different platelets adhere to the polymerizing fibrin, compressing the fibrin nets in their pathway. Since the anchoring of contractile fibers to membranes is crucial for the platelet contractile manifestations, the integrity of the membrane structure should be considered in the study of pathological aspects of platelet function.


Sporulation and C2 toxin production by Clostridium botulinum type C strains producing no C1 toxin.

All of the 8 strains that were previously assumed to be nontoxigenic Clostridium botulinum type C were re-examined for their toxigenicity and were demonstrated by trypsinization of the culture filtrates to produce C2 toxin under improved cultural conditions. One per cent glucose added to trypticase peptone medium enhanced C2 toxin production. The larger the spore population, the higher the C2 toxicity and when spore population was smaller than a level of 10(4)/ml, no C2 toxicity was demonstrated. The C2 toxin was produced only during sporulation and not during vegetative growth.


Treatment of duodenal ulcer with carbenoxolone sodium: a double-masked endoscopic trial.

In a double-masked trial, 43 patients with an endoscopically confirmed, symptomatic duodenal ulcer were allocated at random to treatment with either carbenoxolone sodium or placebo, both provided in identical "positioned-release" capsules. The 40 patients who satisfactorily completed the trial were evenly distributed between the two treatment groups. The groups were well matched with regard to clinical features and initial ulcer size. Endoscopic review of ulcer healing after six weeks' treatment showed that 12 patients (60%) receiving carbenoxolone had healed ulcers, compared with five (25%) receiving placebo (P = 0.05). Symptomatic remission occurred by the fourth week in 17 patients (85%) receiving carbenoxolone, compared with six (30%) receiving placebo (P less than 0.001). The mean (geometric) serum carbenoxolone level in patients with healed ulcers was 31.11 microgram/mL compared with 17.75 microgram/mL in those with unhealed ulcers (P less than 0.005). Side effects of carbenoxolone therapy were observed, but they did not necessitate withdrawal of the drug and were readily controlled in every instance. These results confirm the therapeutic efficacy of carbenoxolone sodium in duodenal ulcer. In addition, a relationship between serum carbenoxolone levels and the occurrence of ulcer healing was observed.


A comparative study of indomethacin and ibuprofen.

In a double blind trial with 20 patients ibuprofen 1600 mg daily and indomethacin 100 mg daily were shown to be of comparable efficacy in the short-term treatment of rheumatoid arthritis. Reported side effects were similar, but a slightly greater incidence of gastric irritation was noted with indomethacin necessitating withdrawal of one patient from the trial. The serum concentrations for indomethacin and ibuprofen were determined for four hours after the last dose. Peak concentrations of both drugs occurred within two hours. Five of the seven patients considered to have comparable serum concentrations of both drugs demonstrated a preference for indomethacin.


Studies with prazosin--a new effective hypotensive agent. III. An acute double-blind cross-over study comparing the effects of single doses of prazosin and hydrallazine in combination with propranolol and a diuretic.

The duration of action of a single dose of prazosin and hydrallazine on blood pressure and heart rate was studied in 16 hypertensive patients whose blood pressure was not adequately controlled by a combination of a thiazide diuretic and a beta-adrenergic blocking agent, and had required the addition of either prazosin or hydrallazine. Observations over an eight-hour period, after a single dose of either 3 mg of prazosin, or 75 mg of hydrallazine, in identical capsules, with cross-over study one week later, showed significant reductions in blood pressure within the first hour after oral administration of either agent. This reduction in blood pressure persisted for four to six hours after hydrallazine and six to seven hours after prazosin administration. Tachycardia was more pronounced and prolonged after hydrallazine administration and side effects were more common.


A transducing lambda phage carrying grpE, a bacterial gene necessary for lambda DNA replication, and two ribosomal protein genes, rpsP (S16) and rplS (L19).

A grpE mutation of Escherichia coli K12, which blocks DNA replication of the phage lambda (Saito and Uchida, 1977), was mapped at 56 min on the standard genetic map. A transducing lambda phage, lambdagrpE22, carrying the wild type allele of the grpE gene was constructed in vitro. Structures of lambdagrpE22 and its viable deletion derivatives were determined by electron microscopic analyses of appropriate heteroduplexes. Proteins coded by the bacterial DNA incorporated into the transducing phages were detected by two-dimensional gel electrophoresis. The results showed that the product of the grpE gene is a weakly acidic protein of molecular weight 24,000. Structural genes for two ribosomal proteins, rplS (L19) and rpsP (S16) were also shown to be carried by lambdagrpE22.


Genes encoding ribosomal proteins S16 and L19 form a gene cluster at 56.4 min in Escherichia coli.

A mutant of Escherichia coli which was isolated for temperature-sensitive growth was found to harbour a structural alterations in protein S16 (Isolo et al., 1978). The mutation was localized by matings with various Hfr strains and by Plkc-mediated transduction. The results showed that it mapped very close to the gene coding for L19 protein which has been placed at 56.4 min (Kitakawa and Isono, 1977), indicating that it most likely forms a new ribosomal protein-gene cluster.


Method of isolation of cysteine constitutive mutants of the cysteine regulon in Salmonella typhimurium.

A method for selection of constitutive cysB mutation is described which takes advantage of the resistance of cysteine constitutive mutants to 1,2,4-triazole. Since cysM cysK double mutants are cysteine auxotrophs, by selecting for triazole resistance in cysM strains, mutants arising under this condition also should be constitutive for cysteine biosynthesis. Genetic analysis of mutants isolated by this technique showed that their mutational sites are located in the cysB region. Biochemical assays of cysteine enzymes, sulphite reductase and O-acetylserine sulfhydrylase of the mutants showed the derepressed level of these enzymes and the lack or slight repression by 1-cysteine.


The control region of the F sex factor DNA  transfer cistrons: restriction mapping and DNA cloning.

A restriction endonuclease map of EcoRI fragment f6 of F sex factor DNA was constructed and aligned with pre-existing physical and genetic maps. Results of genetic complementation tests and analysis of proteins synthesized in minicells from PstI and BglII sub-fragment clones, or from a specific BglII fragment deletion, have allowed mapping of the locations of the origin of DNA transfer and many of the transfer genes known to lie on f6. The proteins detected account for 78% of the coding capacity of fragment f6.


Mapping of RP4 plasmid using deletion mutants of pAS8 hybrid (RP4--ColE1).

We used the hybrid plasmid pAS8 in order to conduct the genetic analysis of RP4 plasmid. The presence of two replicons in the hybrid plasmid permitted to expand the spectrum of deletion mutants of RP4 isolated, which are capable to autonomous replication. The shortening of the hybrid plasmid was achieved by P22 transduction, by induction of deletion mutants using mitomycin C, as well as by seletion of Tra- mutants on the basis of resistance of cells to P-specific phages. These techniques have lead to isolation of clones possessing different combinations of plasmid resistance determinants. Comparison of phenotypic characteristics of deletion plasmids pAS9, pAS10, pAS11, pAS12 and pAS10-2 permitted to propose the map for pAS8 plasmid with the following sequence of markers: tra--kam--ColE1--amp--tet... Heteroduplex analysis of deletion mutants of pAS8 permitted to construct a physical map and to elaborate in greater detail the functional map of RP4 plasmid. The correlation between the ability of mutants to replicate in polA(TS) strain at nonpermissive conditions and the length of the deleted segment permitted to map rep genes of RP4 on a region with coordinates 9.8--17.3 kb. A relationship between the manifestation of incompatibility of mutants with Inc P-1 plasmids and the length of deletions points out that inc genes are located on DNA region with coordinates 2.1--9.8 kb. The analysis of replication of deletion mutants and the manifestation of incompatibility just as of the data about the size of appropriate deletions permitted to make the conclusion about the functional and genetic independence of the replication control and incompatibility control in RP4 plasmid.


On the role of recA gene product in genetic recombination: an analysis by in vitro packaging of recombinant DNA molecules formed in the absence of protein synthesis.

The role of the recA gene product of Escherichia coli in genetic recombination was examined in a system where recombination takes place in the absence of protein synthesis. recA200 bacteria were infected with two mutant strains of phage lambda in the presence of chloramphenicol and rifampin, and the resulting recombinant DNA molecules were measured by in vitro packaging. When recA200 bacteria grown at a temperature that is permissive for RecA phenotype were transferred to a temperature that is restrictive for RecAa phenotype in the presence of the inhibitors, recombination of the infecting phages was severely blocked. This result shows that the recombination activity of the recA200 cells is inactivated by the change of temperature even in the absence of protein synthesis. The most likely explanation of this result is that the recA protein is directly involved in the recombination detected in the presence of chloramphenicol and rifampin.


An "up-promotor" mutation affecting the acetamidase of Aspergillus nidulans.

A derivative of an areA200 strain of Aspergillus nidulans selected for strong growth on acetamide as the sole nitrogen source was found to have a mutation, amd-18, closely linked to amdS, the acetamidase structural gene. This mutation results in 2--3 fold higher acetamidase activities than wildtype strains in uninduced as well as induced cultures. The effects of the amd-18 mutation are superimposed on the effects of other regulatory mutations affecting the acetamidase. The amd-18 mutation is cis-dominant with respect to the amdS gene. Immunological and gel electrophoresis studies have shown that amd-18 strains produce higher levels of acetamidase protein. A previously described cis-dominant mutation, amdI9, also causes elevated levels of acetamidase protein. The amd-18 mutation may affect a promoter site for the amdS gene allowing an increased frequency of transcription.


Mutational analysis of the operators of bacteriophage lambda.

Oc mutations in the operators of bacteriophage lambda have been used to analyze the functional organization of the operators. In each operator, repressor binding sites 1 and 2, as identified biochemically, were found to be primarily responsible for the repressor affinity of the operators in vitro and for the repression of lytic functions in vivo. In addition, both sites were shown to be involved in the action of cro product at the operators. The data obtained have been used to estimate the repressor affinities of the individual binding sites. These affinities suggest that repressor bound at OR1 and OR2 interacts cooperatively. The results obtained support a model for repression of the early lambda operons where repressor bound at binding sites 1 and 2 interferes with RNA polymerase binding to the promotor sites.


Comparison of sensitivity and liquid holding recovery in rad mutants of Saccharomyces cerevisiae inactivated by UV and DEB.

Twenty one UV-sensitive rad mutants were tested for their sensitivity towards DEB. All mutants were more sensitive to this treatment than the wild type. Seven mutants were classified as supersensitive to DEB (rad 1-1, 2,3, 6, 15 and 18-2), while only rad2 and rad3 can be classified as supersensitive to UV. For all mutants ability for liquid holding recovery (LHR) after UV and DEB was compared. Mutants rad 1-1, 3, 5, 6, 9 and 11 differ in their response to LH after the two treatments. Survival of rad1-1 and rad3 increases signficantly during LH after DEB but not after UV exposure. In contrast rad5, 6, 11, and 22 show marked LHR after UV but no increase of survival after DEB treatment.


lambdaimm P22dis: a hybrid of coliphage lambda with both immunity regions of Salmonella phage P22.

Genetically marked lambda and P22 phages were recombined in Escherichia coli-Salmonella typhimurium hybrid WR4028, a host sensitive to infection by both of these phages. Hybrid phages that acquired the immC region of P22, but retained the genes for the lambda protein coat were selected on WR4027 (lambda), a lambda-immune, P22-resistant derivative of WR4028. In these lambdaimmP22 hybrids, at least the c through P genes of lambda were replaced with functionally related P22 genes. Phage recombinants with more extensive regions of the P22 genome were selected on the double lysogen WR4027 (lambda, lambdaimmP22). One such hybrid, lambdaimmP22dis, was determined by heteroduplex analysis to contain approximately 40% of the P22 genome. Genetic studies established that lambdaimmP22dis possesses the two widely separated immunity control regions of P22 (immC and immI) and that these loci are expressed in E. coli K-12 lysogenic for lambdaimmP22dis. In addition, lambdaimmP22dis contains the P22 a 1 locus responsible for somatic 0--1 antigen conversion in Salmonella. Although the lambdaimmP22dis phage particle has the lambda head and tail, the phage genome also carried P22 tail gene 9 as evidenced by the production of free P22 tails. It also has the P22 att site as indicated by the integration of the lambdaimmP22dis prophage near the proA locus on the bacterial chromosome.


Restriction enzyme cleavage of DNA resulting from gently lysed Escherichia coli.

When E. coli or lambda infected E. coli are gently lysed the DNA is released as a very fast sedimenting species that is presumably bound to membrane material. If this complex is now subjected to restriction enzyme cleavage, only a minor fraction of the fast sedimenting DNA remains and this is found, after purification, to be enriched for branched molecules.


The regulation of urea amidolyase of Saccharomyces cerevisiae: mating type influence on a constitutivity mutation acting in cis.

Constitutivity for the synthesis of the urea amidolyase bienzymatic complex is obtained by durOh mutations located in the regulatory genetic region adjacent to the dur1, dur2 gene cluster. The durOh mutations act only in cis and are a new case of cis effect strongly cancelled in alpha/a diploid, similar to cargA+Oh mutation shown previously to lead to arginase constitutivity. Illegitimate diploids do not show such a cancellation of constitutivity. The constitutivity produced by durOh mutation comprises the process of induction and the release of the glutamine effect. It does not impair the NH+4 effect.


Map location of the Escherichia coli origin of replication.

Working with restriction fragments obtained directly from the Escherichia coli K12 chromosome, the EcoRI-HindIII restriction map of the section of the chromosome containing the replication origin has been extended by 14 kilobase pairs (kb) to cover 56 kb. Within this newly mapped portion, the ilv and rrnC cistrons have been identified by (1) hybridization of individual restriction fragmanents to the ilv-transducing phage lambdadilv5 and (2) a comparison of the restriction map of this region with the EcoRI map of lambda dilv5 and the Hind III map of the plasmid pJC110, a ColEl-ilv hybrid. The replication origin is located approximately 30 kb from the ilvE gene and 20 kb from the rrnC 16S rRNA cistron. This places the origin near 82.7 min on the genetic map, close to uncA.


Isolation and characterization of a ColE1 plasmid containing the entire bio gene cluster of Escherichia coli K12.

ColE1amp plasmids carrying the entire bio gene cluster were constructed in vitro using ColE1amp as the cloning vehicle and a lambda transducing phage, lambdaatt2, as the source of bio DNA. Restriction endonuclease EcoRI digests of ColE1amp and lambdaatt2 DNA were joined by polynucleotide ligase and plasmids bearing the entire bio gene cluster were selected, after transformation, in bio deletion strains of E. coli. Recombinant DNA molecules contained one ColE1amp fragment (7.4 X 10(6) daltons) and one lambdaatt2 DNA fragment (5.4 X 10(6) daltons). Clones carrying ColE1 amp-bio plasmids produce elevated levels of biotin and biotin synthetase activity.


Lactam utilisation in Aspergillus nidulans: evidence for a fourth gene under the control of the integrator gene intA.

Mutations in the lamA gene of Aspergillus nidulans prevent the conversion of exogenous 2-pyrrolidone (gamma-butyrolactam) to gamma-amino-n-butyrate (GABA) and also prevent the (probably analogous) utilisation of 2-piperidone (sigma-valerolactam). The lamA gene, in linkage group VIII, probably specifies a lactamase but a rôle in lactam uptake cannot be ruled out. lamA is probably under the control of the positive acting regulatory gene intA, which can integrate its expression with the expression of three other genes, specifying acetamidase, GABA transaminase, and GABA permease, respectively.


Functional mRNA half lives in E. coli.

Analysis of the synthetic rate of individual protein species at various times after complete inhibition of transcription with either streptolygidin or rifampicin was carried out by two-dimensional polyacrylamide electrophoresis of total Escherichia coli cell extracts. The decay rate of the potential to synthesize different proteins was assumed to be equal to the functional decay rate of the corresponding mRNA. We conclude the following: (a) The tufA and tufB messengers have different half lives (3.0 and 2.4 min, respectively). (b) Different genes within the same transcriptional unit can have different half lies (S7, EGF and EFTuA--2.5, 3.8 and 3.0 min, respectively). (c) There is at least a twenty-fold variation in individual mRNA half lives in E. coli; ribosomal protein S1 mRNA was observed to have the shortest half life in the cell (40 sec), while the longest observed half life was approximately 20 min (all values at 30 degrees C). (d) Addition of rifampicin increases the absolute rate of RNA polymerase subunit alpha and beta synthesis two-fold. (e) The induction of the synthesis of alpha subunit of RNA polymerase takes place without a concomitant induction of ribosomal protein S4 and L17, which are reported to be on either side of alpha in the same transcriptional unit.


Instability of plasmid DNA sequences: macro and micro evolution of the antibiotic resistance plasmid R6-5.

Detailed examination of the structure of cloned DNA fragments of the R6-5 antibiotic resistance plasmid has revealed a substantial degree of polynucleotide sequence heterogeneity and indicates that sequence rearrangements in plasmids and possible other replicons occur more frequently than has hitherto been appreciated. The sequences changes in cloned R6-5 fragments were shown in some instances to have occurred prior to cloning, i.e. existing in the original population of R6-5 molecules that was obtained from a single bacterial clone and by several different criteria judged to be homogeneous, and in others to have occurred either during the cloning procedure or during subsequent propagation of hybrid molecules. The molecular changes that are described involved insertion/deletion of the previously characterized IS2 insertion element, formation of a new inverted repeat structure probably by duplication of a preexisting R6-5 DNA sequence, sequence inversion, and loss and gain of restriction endonuclease cleavage sites.


Nitrite reduction in Escherichia coli: genetic analysis of nir mutants.

Five mutants of Escherichia coli impaired on nitrite reduction were studied. All have lost NADH-nitrite reductase activity but have retained the capacity to synthesize all or part of their cytochrome c552. Three genes, nir C, nir D, and nir E were mapped at 26, 72.5 and 49.5 min, respectively. Another gene, nir F was tentatively localized around 52 min.


Altered DNA-protein relaxation complex in a replication mutant of plasmid ColE1.

Approximately 200,000 clones of Escherichia coli carrying mutagen-treated colicinogenic plasmid E1 (ColE1) were examined for irreversible loss of the plasmid at 43 degrees. Thirty of these clones that appeared to be most defective in plasmid DNA replication at the non-permissive temperature were selected for the study of: (a) the kinetics of plasmid and chromosomal DNA replication during a temperature shift in either the presence or absence of chloramphenicol; (b) the temperature stability of the plasmid DNA-protein relaxation complex; and (c) the temperature effect on F-promoted conjugal transfer. Two mutant plasmids, pJC307 and pJC301, showed defects in their relaxation complex. The relaxation complex of pJC307 exhibited an altered temperature stability in vitro. Reversion to temperature resistant replication resulted in four out of five cases in a concomitant change in the temperature stability of the relaxation complex. Conjugal mobility of this mutant was not markedly reduced at the permissive or non-permissive temperature. Plasmid pJC301 could not be isolated in the form of a relaxation complex and it was very poorly mobilized in an F'-promoted conjugation. These results indicate that the ColE1 plasmid codes for at least one of the proteins of the relaxation complex and that the relaxation complex is involved in ColE1 DNA replication. In addition, the properties of the mutant plasmid pJC301 are consistent with a role for the complex in the mobilization of ColE1 during conjugation.


The involvement of DNA polymerase I in the postreplication repair of ultraviolet radiation-induced damage in Escherichia coli K-12.

A deficiency in DNA polymerase I increased the ultraviolet (UV) radiation sensitivity of a uvrA strain of Escherichia coli K-12 when plated on minimal growth medium. The slope of the survival curve for the uvrA polA strain was 2.0-times greater than that for the uvrA strain. The fluence-dependent yield of unrepaired deoxyribonucleic acid (DNA) parental-strand breaks following UV irradiation and incubation in minimal growth medium was similar in both strains. However, the fluence-dependent yield of unrepaired DNA daughter-strand gaps observed following UV irradiation was 1.8-fold greater in the uvrA polA strain than in the uvrA strain. These results suggest that DNA polymerase I is involved in the filling of at least some daughter-strand gaps during postreplication repair. Also, the uvrA polA strain was sensitized by a post-UV treatment with chloramphenicol (CAP) to a similar extent as was the uvrA strain, indicating that DNA polymerase I is not involved in the CAP-inhibitable pathway of postreplication repair.


Analysis of regulatory mechanisms controlling the activity of the hexitol transport systems in Escherichia coli K12.

The transport systems (enzymeII-complexes of the PEP-dependent sugar:phosphotransferase system) coded for in the mtl and in the gut (srl) operon of E. coli K12 have been shown to be the pacemaker enzymes in the catabolism of the two hexitols D-mannitol and D-glucitol, respectively. As for other pacemaker enzymes their activity is regulated in a complex way: (i) via competitive inhibition by analogues. (ii) via non-competitive (feedback) inhibition by the simultaneous, rapid uptake of a number of structurally related or non-related carbohydrates, regardless if these are transported by group translocation, active transport or facilitated diffusion. This type of inhibition is strongly reinforced, if the inhibitory carbohydrates are converted efficiently into hexose-phosphates at the same time. Among these, predominantly D-fructose-6-P seems to act as a feedback inhibitor for the hexitol specific enzymeII-complexes: (iii) inhibition of hixitol-phosphate accumulation by D-glucose-6-P. The influence of additional parameters (PEP level, P approximately HPr level) and indications for the existence of further mechanisms controlling the activity of hexitol and other carbohydrate transport systems will be discussed, as will be the part the inhibitory mechanisms described above play in the phenomena of transient repression and inducer exclusion.


Regional replication of the bacterial chromosome induced by derepression of prophage lambda. IV. Escape synthesis of gal operon in phage 82.

Derepression of prophage lambda in E. coli strain K12 results in constitutive synthesis of the enzymes directed by the nearby bacterial operon, gal (escape synthesis). Phage 82 fails to cause escape synthesis despite that it lysogenizes the strain K12 at the site identical to that of lambda on the host chromosome. The reason for the observed difference between 82 and lambda is studied in the light of the recent finding that escape synthesis in lambda-lysogen is closely associated to phage-promoted replication of bacterial chromosome contiguous to the prophage including gal operon (escape replication). Excision-defective mutants from 82, 82int or 82xis, do initiate escape synthesis, suggest that the prophage 82 is normally excised too quickly after induction to allow sufficient escape replication. In support of this, much more DNA hybridizable to bacterial DNA contained in lambdagal accumulates after induction if 82int than after induction of 82. Studies with various hybrid phages between 82 and lambda have suggested: 1. The occurrence of gal escape synthesis depends on the nature of the region between b2 and N in the lambda map. 2. Regions of the 82 genome on both sides of the attachment site contribute independently to prevent gal escape synthesis. Implications of these results are discussed with regard to the factors involved in the prophage excision.


Close vicinity of IS1 integration sites in the leader sequence of the gal operon of E. coli.

Four insertions of IS1 in the leader sequence of the gal operon of E. coli have been analysed. Two of them occur at the same position, but in opposite orientations. The other two are inserted one nucleotide to one side and four nucleotides to the other side, respectively. In each case, nine base pairs of the leader sequence of the gal operon are duplicated directly, and are found flanking the termini of IS1 at its junction with the gal operon. These repeated sequences differ from each other as expected from the different insertion sites.


Suppression of mitochondrially-determined resistance to chloramphenicol and paromomycin by nuclear genes in Saccharomyces cerevisiae.

Phenotypic "revertants" of a drug resistant strain of Saccharomyces cerevisiae were induced by mutgenesis with manganese. Several of these drug sensitive mutants have been shown to result from mutations in the nuclear genome that cause phenotypic modification (suppression) of the mitochondrially-determined drug resistant genotype. Four mutants carrying a single recessive nuclear gene capable of modifying mitochondrial chloramphenicol resistance are described; these may be assigned to three complementation groups. Chloramphenicol resistant mutants mapping at five separate mitochondrial loci are described. At least two of the nuclear genes cause modification of mitochondrial chloramphenicol resistance determined by mutations at three of these loci, but the other two loci are apparently non-suppressible by these nuclear alleles. This indicates that these modifiers do not act by causing a general decrease in cellular or mitochondrial permeability to the drug. A single dominant nuclear modifier of mitochondrial paromomycin resistance has been identified. It is non-allelic to and does not interact with the genes modifying mitochondrial chloramphenicol resistance.


Repair of MMS-induced DNA double-strand breaks in haploid cells of Saccharomyces cerevisiae, which requires the presence of a duplicate genome.

The formation and repair of double-strand breaks induced in DNA by MMS was studied in haploid wild type and MMS-sensitive rad6 mutant strains of Saccharomyces cerevisiae with the use of the neutral and alkaline sucrose sedimentation technique. A similar decrease in average molecular weight of double-stranded DNA from 5--6 X 10(8) to 1--0.7 X 10(8) daltons was observed following treatment with 0.5% MMS in wild type and mutant strains. Incubation of cells after MMS treatment in a fresh drug-free growing medium resulted in repair of double-strand breaks in the wild type stain, but only in the exponential phase of growth. No repair of double-strand breaks was found when cells of the wild type strain were synchronized in G-1 phase by treatment with alpha factor, although DNA single-strand breaks were still efficiently repaired. Mutant rad6 which has a very low ability to repair MMS-induced single-strand breaks, did not repair double-strand breaks regardless of the phase of growth. These results suggest that (1) repair of double-strand breaks requires the ability for single-strand breaks repair, (2) rejoining of double-strand breaks requires the availability of two homologous DNA molecules, this strongly supports the recombinational model of DNA repair.


Genetic localization of diuron- and mucidin-resistant mutants relative to a group of loci of the mitochondrial DNA controlling coenzyme QH2-cytochrome c reductase in Saccharomyces cerevisiae.

Diuron-resistance, DIU (Colson et al., 1977), antimycin-resistance, ANA (Michaelis, 1976; Burger et al., 1976), funiculosin-resistance, FUN (Pratje and Michaelis, 1977; Burger et al., 1977) and mucidin-resistance, MUC (Subik et al., 1977) are each coded by a pair of genetic loci on the mit DNA of S. cerevisiae. In the present paper, these respiratiory-competent, drug-resistant loci are localized relative to respiratory-deficient BOX mutants deficient in coenzyme QH2-cytochrome c reductase (Kotylak and Slonimski, 1976, 1977) using deletion and recombination mapping. Three drug-resistant loci possessing distinct mutated allelic forms are distinguished. DIU1 is allelic or closely linked to ANA2, FUN1 and BOX1; DIU2 is allelic or closely linked to ANA1, MUC1 and BOX4/5; MUC2 is allelic to BOX6. The high recombinant frequencies observed between the three loci (13% on the average for 33 various combinations analyzed) suggest the existence of either three genes coding for three distinct polypeptides or of a single gene coding for a single polypeptide but subdivided into three easily separable segments. The resistance of the respiratory-chain observed in vitro in the drug-resistant mutants and the allelism relationships between respiratory-competent, drug-resistant loci and coQH2-cyt c reductase deficient, BOX, loci strongly suggest that each of the three drug-resistant loci codes for a structural gene-product which is essential for the normal coQH2-cyt c reductase activity and is obviously a good candidate for a gene product of the drug-resistant loci mapped in this paper. Polypeptide length modifications of cytochrome b were observed in mutants deficient in the coQH2-cyt c red and localized at the BOX1, BOX4 and BOX6 genetic loci (Claisse et al., 1977, 1978) which are precisely the loci allelic to drug resistant mutants as shown in the present work. Taken together these two sets of data provide a strong evidence in favor of the idea that there exist three non contiguous segments of the mitochondrial DNA sequence which code for a single polypeptide sequence of cytochrome b. In each segment mutations which modify the polypeptide sequence can occur leading to the loss (BOX mutants) or to a modification (drug resistant mutants) of the enzyme activity.


Allelism relationships between diuron-resistant, antimycin-resistant and funiculosin-resistant loci of the mitochondrial map in Saccharomyces cerevisiae.

Using allelism tests, two diuron (DIU1, DIU2), one funiculosin (FUN1), and two antimycin (ANA1, ANA2) resistance loci are resolved into two mitochondrial drug-resistant genetic loci. DIU1 is alelic to ANA2 and FUN1. DIU2 is allelic to ANA1.


Segregation of the mutator property of plasmid R46 from its ultraviolet-protecting property.

Plasmid R46 (an R factor conferring resistance to ampicillin, sulfonamides, streptomycin and tetracycline) reduces the bactericidal effect of UV irradiation but increases its mutagenic effect (reversion of hisG46), and raises the frequency of spontaneous reversion (mutator effect). Putative deletion mutants of R46 were obtained by transduction of the plasmid, then two successive conjugal transfers. Plasmids of five of six deletion classes, each with a different combination of drug resistance traits, retained conjugative ability and the UV-protecting, mutagenesis-enhancing and mutator effects of R46. (pKM101, used in the Ames system to enhance responsiveness to chemical mutagens, is one such mutant of R46.) Plasmids of a sixth class, represented by pKM115, conferred resistance only to streptomycin and were non-conjugative. All of several such plasmids (of independent origin) had a much stronger mutator effect than did R46, but lacked UV-protecting ability and did not enhance the mutagenic effect of UV irradiation. We infer that R46 possesses: (i) a gene, uvp, which increases capacity for error-prone repair of UV-damaged DNA, and thus causes both UV protection and enhancement of UV mutagenesis; (ii) gene(s) whose action in the absence of gene uvp greatly increases the frequency of spontaneous reversion of hisG46. A plasmid of another incompatibility group, pLS51, has UV-protecting and mutagenesis-enhancing effect but lacks the mutator property; introduction of pLS51 into a clone of hisG46 carrying a pKM115-type plasmid greatly reduced its spontaneous reversion rate, as expected if pLS51 also has a uvp gene able to modulate the mutator effect of R46-derived gene(s) in the pKM115-type plasmid.


Repressor synthesis in regulatory mutants of bacteriophage P22.

SDS-polyacrylamide gel analysis of P22-infected Salmonella has allowed identification of the c2 repressor (MW 31,000) and study of repressor synthesis in regulatory mutants of P22. Repressor is synthesized in reduced amounts or is absent in infections with P22, clNo.7, P22, c2 am08, P22 c3 am03, and P22 c3 am012, but is synthesized in markedly increased amounts in the virulent mutant, P22 virB3, and its component mutants, vx and k5. Higher levels of repressor are also found in the P22 cly 17 mutant.


A method for purification of peptides from hydrolysates of proteins modified by chemically active analogues of substrates containing cis-diol groups.

A simple and rapid column procedure is described for the isolation from protein hydrolysates of peptides containing covalently bound substrate analogues with cis-diol groups. The method is based on complex formation between the cis-diol groups of peptide-bound compounds and dihydroxyborylic groups of a dihydroxyborylaminoethyl cellulose column. The method is useful for isolation of peptide(s) located in or near the active centre of enzymes after their affinity labelling by chemically active analogues of natural substrates like ribonucleotides, sugars, etc.


[Arrangement in chromatin of DNA sites accessible to Serratia marcescens endonuclease].

Splitting of DNA in rat thymus nuclei by Serratia marcescens endonuclease has been studied. DNA fragments were analyzed by gel electrophoresis. Obtained data indicate that the internucleosomal DNA interacts with histones octamer and is cut by endonuclease to fragments multiple of 10 nucleotides. Limits digestion of nuclei with Serratia endonuclease (up to 50% of DNA acid solubility) leaves in a nondegraded form the chromatin fragments including DNA pieces up to 1000 bases in size-resistant DNA. Partly, the resistant DNA has properties of single-stranded molecules. These data are interpreted so that Serratia endonuclease is able to hydrolyse with some preference one of the DNA strands in chromatin. It can be considered as an evidence of different modes of interaction of the histone core with the two DNA strands.


[Modification of one tRNA recognition site of phenylalanyl-tRNA synthetase from E. coli MRE-600 with N-chlorambucilyl-phenylalanyl-tRNA].

Affinity labelling of phenylalanyl-tRNA synthetase from E. coli MRE-600 with N-chlorambucilyl-phenylalanyl-tRNA results in a binding of 1 mole of the reagent per 1 mole of the enzyme. Exhaustive alkylation of phenylalanyl-tRNA synthetase completely blocks the aminoacylation and partially inhibits the reaction of ATP--[32P]pyrophosphate exchange. Removal of the tRNA moiety of the reagent by hydrolysis of the ester bond N-chlorambucilyl-phenylalanine and terminal adenosine does not result in a restoration of ATP--[32P]pyrophosphate exchange and aminoacylation activity. The latter result may testify a chemical modification of amino acid residues essential for enzymatic activity. Possibility of blocking one of the two tRNA binding sites is discussed.


[Role of the lysine residues in the phenylalanyl-tRNA synthetase substrates interaction].

The effect of 2,4-pentandione on the activity of phenylalanyl-tRNA synthetase (Phe-RSase) from E. coli MRE-600 was investigated. It was shown that modification of Phe-RSase with 2,4-pentandione leads to decrease of the aminoacylation rate without an influence on the ATP--[32P]pyrophosphate exchange reaction rate. tRNAPhe protects the enzyme against inactivation. Neither L-Phe and ATP nor the analog fo aminoacyladenylate protects the enzyme against inactivation. There are no changes in Km for amino acid and ATP in the aminoacylation reaction after modification while Km for tRNAPhe decreases three times. The dissociation constant of Phe-RSase: [14C]Phe-tRNA complex increases 4--8 times after modification. It is assumed that there are some lysine residues in Phe-RSase essential for the Phe-RSase-tRNA interaction.


[Thermal denaturation of pepsin in crystal form and in solution].

Thermal transitions in pepsin crystals were studied by scanning microcalorimetry and microscopy. A sharp dependence of thermal transition parameters upon the heating rate was discovered. It was determined that during the heating of pepsin crystals it is possible to observe phase transition of the first order type. Thermal transition is connected only with the denaturation of protein molecules in the crystal. The absence of crystals melting was shown with the help of microscopy. The coincidence of equilibrium denaturation temperatures of pepsin in crystal and in solution was shown in direct calorimetric experiments. The results obtained point to the fact that intermolecular interactions do not give any contribution to the thermostability of hydrated supermolecular protein systems.


[Congenital malaria in a Greek twin (author's transl)].

A case of congenital malaria due to Plasmodium malariae in one of two living Greek twins born in Germany is presented. In the child fever, anaemia and hepatosplenomegaly were first noticed at the age of two months. Plasmodium malariae parasites were demonstrated in the peripheral blood and bone marrow. The sera of mother and infant contained malaria antibodies. However the mother never showed clinical signs of malaria. Diagnosis and therapy of congenital malaria and the possible mode of transmission of this rare disease are discussed.


[Brain oligopeptides--analgesic peptides, stimulators of memory and sleep].

A review of recent advances in the structure and properties of brain endogenous oligopeptides and their analogs is given. The principal attention is drawn to the stimulators of learning long-term memory, sleep and analgetic oligopeptides.


[Specific cleavage of glycosylyl denatured DNA of T2 and T4 phages adjacent to the oligothymidilic or oligoadenylic sequences].

A method of complementarily directed alkylation with following elimination of the alkylated bases and with DNA cleavage at apurinic sites was used for specific fragmentation of glucosylyl DNA of T2 and T4 phages. It was shown that denatured glucosylyl T2 and T4 DNA's are modified by alkylating derivatives of hexaadenylate and heptauridylilate. The extent of alkylation reached the maximum and then stopped. The extent of elimination and chain cleavage corresponded to that of alkylation. Treatment of DNA after alkylation with (Ap)5ARCl under condition of saturation at 20 degrees gives 572 +/- 28 fragments from T4 DNA with 200--25,000 nucleotides long and 578 +/- 33 fragments from T2 DNA. Alkylation under condition of DNA saturation with (Ap)5ARCl at 40 degrees leads to 138 +/- 15 fragments from T4 DNA and 170 +/- 16 fragments from T2 DNA. Characteristics of the fragments obtained are given.


In vitro breakage of plasmid DNA by mutagens and pesticides.

Covalently closed circular molecules of the colicinogenic plasmid E1 can serve as sensitive indicators for detecting in vitro breakage of DNA. After these molecules are radioactively labeled and purified by cesium chloride density-gradient centrifugation, they are incubated with the compounds to be tested. Samples are analyzed on alkaline sucrose gradients to determine the fraction of unbroken molecules and a breakage rate is calculated. Positive results were obtained for all three mutagenic alkylating agents (MMS, EMS, and MNNG) and of the 11 pesticides tested, dexon, dichlorvos, malathion, and methyl parathion induced breaks in molecules at a rate significantly greater than the controls.


A new method for the preparation of mammalian spermatogonial chromosomes.

After the seminiferous tubules were minced and washed with phosphate-buffered saline to remove sperms, spermatids and spermatocytes (Hoo and Bowles, 1971), they were repeatedly treated with 0.1% trypsin solution to liberate spermatogonia. It was concluded that the spermatogonial chromosomes can be analysed much more easily and accurately by this procedure than by previous ones.


Deuterium isotope effects in mutagenesis by nitroso compounds.

Nitrosamines which have deuterium instead of hydrogen in the position alpha to the nitroso group have been reported to have reduced activity in carcinogenicity tests. This result implies that cleavage of a carbon--hydrogen bond is a limiting step in the reaction mechanism leading to tumor formation. Mutagenicity tests were undertaken with nitrosamines, which require metabolic activation, and with nitrosamides, which are directly acting mutagens, to determine the effect of deuterium substitution on the activity of each type of compound. Two nitrosamides (N-methyl-N'-nitro-N-nitrosoguanidine and methylnitrosourea) and three nitrosamines (dimethylnitrosamine, nitrosomorpholine, and dinitrosopiperazine) and their deuterium-containing analogs were tested for reversion of a nonsense mutation in the tyr locus of Escherichia coli WU 3610 (tyr-, leu-). Nitrosamines activated by rat-liver microsomes, but not nitrosamides, were less active as mutagens when the deuterium atom was present. The results suggest that the metabolic activation of nitrosamines to a mutagenic species involves the loss of hydrogen, a reaction which the nitrosamides, in the absence of enzyme, do not undergo.


Differential mutagenicity of N-methyl-N-nitrosocarbamate insectides in Escherichia coli strains having different DNA repair capacities.

Four isogenic strains of Escherichia coli with the same auxotrophic marker (arg Fam--namely wild-type, uvrA-, polA- and recA-) were used for testing the lethalities and mutagenicities of 1-naphthyl N-methyl-N-nitrosocarbamate (nitroso-NAC), 3-methylphenyl N-methyl-N-nitrosocarbamate (nitroso-MTMC), and 3,4-dimethylphenyl N-methyl-N-nitrosocarbamate (nitroso-MPMC). The strains recA- and polA- showed a similarly higher sensitivity to killing than wild-type and uvrA- after treatments with each of the three chemicals, whereas the strains wild-type, uvrA-, and polA- were equally mutable by these compounds at equal doses. The strain recA- was hardly mutable by nitroso-NAC, but significant levels of Arg+ mutations were observed after treatments with nitroso-MTMC and nitroso-MPMC. These and previous results suggest that both nitroso-MTMC and nitroso-MPMC are similar in their mutagenicity pattern to N-methyl-N'-nitro-N-nitrosoguanidine whereas nitroso-NAC is similar to methyl methanesulfonate or X-rays, and that the major damage to DNA of the three agents is not excisable by the uvrA+-dependent excision repair, probably methylation in DNA.


A simple plate test for screening colicine-inducing substances as a tool for the detection of potential carcinogens.

A simple and rapid plate test is described for screening substances that induce colicine E2. By using chemicals activated with microsomal enzymes and a permeable (rfa) tester bacterium that is also deficient in DNA repair (uvrB), the range of inducing substances that can be detected has been extended. The possible correlation between colicine-inducing substances and carcinogens is discussed.


Mutagenicity of plant flavonoids: structural requirements for mutagenic activity in Salmonella typhimurium.

40 compounds structurally related to the plant flavonol quercetin were tested for mutagenic activity in Salmonella typhimurium strain TA98. 10 flavonols, quercetin, myricetin, rhamnetin, galangin, kaempferol, tamarixetin, morin, 3'-O-methylquercetin, 7,4'-di-O-methylquercetin and 5,7-di-O-methyl-quercetin, exhibited unequivocal mutagenic activity. 4 compounds, quercetin, myricetin, rhamnetin and 5,7-di-O-methylquercetin, were active without metabolic activation, although metabolic activation markedly enhanced their activity. All 4 have free hydroxyl groups at the 3' and 4' positions of the B ring. The other active compounds required an in vitro rat-liver metabolizing system for significant activity. Structural features which appear essential for mutagenic activity in this strain are a basic flavanoid ring structure with (1) a free hydroxyl group at the 3 position, (2) a double bond at the 2, 3 position, (3) a keto group at the 4 position, and (4) a structure which permits the proton of the 3-hydroxyl group to tautomerise to a 3-keto compound. The data are consistent with the requirement for a B ring structure that permits oxidation to quininoid intermediates. Free hydroxyl groups in the B ring are not essential for activity if a rat-liver metabolic activating system is employed. Data from 12 compounds which differ only at the essential sites described above indicate that the structural requirements for mutagenicity in strain TA100 are the same as those for activity in strain TA98. Based on the above structural requirements, a metabolic pathway for flavonol activation to DNA-reactive species is proposed.


Forward mutations to arabinose resistance in Salmonella typhimurium strains: a sensitive assay for mutagenicity testing.

The forward-mutation assay using the L-arabinose-sensitive strain SV3 of Salmonella typhimurium has been calibrated against a selected set of mutagens. Strain SV3 is sensitive to chemicals causing base-pair substitutions, frameshift mutations and deletions. New strains deficient for the excision-repair system or the lipopolysaccharide barrier or both have been selected from strain SV3. The additional mutations do not affect the independence of the assay from experimental artifacts due to physiological or lethal damage or differences in plating density. The new strains are more sensitive than SV3 to certain mutagens. Techniques for using this set of strains are presented and their relative advantages discussed.


Cytotoxic effects of maleic hydrazide.

Since 1950, maleic hydrazide (MH) has been introduced into agriculture as a major commercial herbicide and a depressant of plant growth in numerous circumstances such as suppression of sprouting of vegetables and stored food crops, control of sucker growth on tobacco plants, ratardation of flowering and prolongation of dormancy period. Since 1951 MH has been known as an effective chromosome-breaking agent in higher plants, in sharp contrast with its low effect on the chromosomes and general health of tested mammals. The selectivity of action of MH in plants and animals was obviously the main reason of low interest devoted to the chemical by people working the field of environmental mutagenesis. In early works the inhibitory effects of MH on plant growth were mainly considered to result from the suppression of plant metabolism (inhibition of enzymic activity) and interference of the compound with plant hormones and growth regulators. More recently, numerous experiments performed with various plant species have shown that MH acts as an inhibitor of the synthesis of nucleic acids and proteins. Similar results have been obtained with animal tumour cells. The chromosome-breaking effect of MH on plant chromosomes resembles very closely the chromosome-breaking properties of alkylating agents and other mutagenic compounds such as mitomycin C. MH-induced chromosomal aberrations have also been recorded in grasshoppers, fish and mice, although tests with some mammalian cell lines gave negative results. Among higher plants, selective sensitivity to the toxic effects of MH is well proved. This phenomenon seems to be due to the differential ability of various plant species to detoxicate the chemical. Plants can break down MH into several products, one of which, hydrazine, is a well-known mutagen and carcinogen. MH does not seem to be toxic to bacteria and fungi. The compound is degraded by soil microflora and hence can be utilized as a source of nitrogen nutrition. MH proved to be of low toxicity to mammals, but in some instances it decreased the fertility of rats. The reported carcinogenic effects of MH in mice and rats raise the question of its risks to man.


Identification of a single promoter in E. coli for rplJ, rplL and rpoBC.

A set of restriction fragments cloned into phage lambda vectors has allowed us to locate a site necessary for full rpoBC expression. We find that these genes for the two large subunits of RNA polymerase and the genes, rplL and rplJ, for two ribosomal proteins, form a single operon.


The E. coli gene encoding heat stable toxin is a bacterial transposon flanked by inverted repeats of IS1.

Restriction endonuclease subclones of the Escherichia coli gene encoding the heat stable (ST) toxin exhibit a stem and loop structure similar to those seen in many procaryotic transposons. An EcoRI DNA fragment encoding tetracycline (Tc) resistance but no transposition functions was spliced into the ST gene in one of these subclones. By monitoring Tcr, we were able to show that the ST gene transposes. Restriction and DNA sequence data strongly suggest that the ST transposon, Tn 1681, is flanked by inverted repeats of IS1.


Escherichia coli mutants accumulating the precursor of a secreted protein in the cytoplasm.

The maltose binding protein of Escherichia coli is secreted into the external periplasmic compartment of the cell. This article describes a selection procedure for the isolation of mutants which fail to export this protein. These mutants probably result from alterations in the amino terminal 'signal sequence', causing the maltose binding protein produced to accumulate in the cytoplasm in its precursor form.


Transcription and processing of cloned yeast tyrosine tRNA genes microinjected into frog oocytes.

Xenopus oocytes transcribe cloned yeast tyrosine tRNA genes and process the RNA. The processing includes base modifications, addition of the CCA end, and splicing of the intervening sequence. The primary transcript has a 5' leader extension which varies considerably in seuqence and in length between different tRNATyr loci, but is nevertheless present in all of them.


Bacterial flora in the digestive tract of cattle. I. Comparison of nonselective culture medium and changes in fecal bacterial flora with age.

Studies were made on nonselective culture medium and the method of culture for the investigation of the bacterial flora in the digestive tract of cattle. With their results, further studies were done to clarify changes in the fecal bacterial flora in eight calves less than 6 months of age with the lapse of time. Three roll-tube media were used in the gas jet method. They were modified VL agar (VL medium), rumen fluid glucose cellobiose agar (RGCA medium), and Medium 10 (M 10). Moreover, glucose liver blood agar (BL medium) was used in the anaerobic jar method. In this method the steel wool method was applied after the substitution of carbon dioxide. Of the four media used, VL medium was proved to be the most efficient. It was followed by RGCA medium and M 10. BL medium was much less efficient than any other medium. When the fecal bacterial flora was examined in calves for changes with the advance in age, the total bacterial count and the enteric bacterial count decreased in the second half of the experimental period. The lactobacillary group count remained almost at a constant level of 7 approximately 9 (logarithmic value) per gram in breast-fed calves, but decreased to a level of 5 (logarithmic value) per gram in bottle-fed calves at about 2 months of age or later. The streptococcal group count showed no particular tendency to change. When the organic acid contents of the feces were estimated in calves in every stage of growth, the amount of total organic acids and that of propionic acid were larger in bottle-fed than in breast-fed calves.


A possible relationship between Henoch-Schonlein syndrome and IgA nephropathy (Berger's disease). An illustrative case.

A 29-year-old white male with the Henoch-Schonlein syndrome and rapidly progressive glomerulonephritis received a kidney transplant. Postransplant, a glomerulonephritis histologically and immunologically indistinguishable from IgA nephropathy (Berger's disease) developed in the absence of any extrarenal manifestations of the Henoch-Schonlein syndrome. A possible pathogenetic interrelationship between these two diseases is discussed.


Treatment of patients with neurological deficits associated with cerebral vasospasm by intravascular volume expansion.

Four patients, including one preoperative patient, developed neurological deficits associated with angiographically proven cerebral vasospasm and were treated with intravascular volume expansion. Indicator dilution techniques were employed to monitor intravascular volume and cardiac functions during treatment. All four patients improved promptly. None of the patients developed cardiac or pulmonary dysfunction despite marked increase in intravascular volume and despite several risk factors such as cardiac symptoms, electrocardiographic abnormalities, and advanced age. The techniques of monitoring and controlling intravascular volume are described. We believe that this is an important therapeutic adjunct for certain aneurysm patients.


Unique aspects of central nervous system immunology.

In this review the authors discuss three immunologically unique aspects of the central nervous system (CNS). The first relates to whether the CNS is really an immunologically privileged site. Although still somewhat controversial, the answer to that question is that the CNS is, to a large extent, an immunologically privileged site. The second unique aspect of the CNS is the origin and significance of the microglial cell. Some microglial cells seem to originate from the systemic circulation, whereas other microglial cells seem to have a primary CNS origin. The function of the microglial cell is that of a macrophage. In addition it may play an important role in the immune response of the CNS. Present evidence suggests that the microglial cell can be classified as a lymphoreticular cell and as such is the only member of this cell type present in the CNS under normal circumstances. The final unique aspect of the central nervous system is the cerebrospinal fluid (CSF). Under normal circumstances this fluid is essentially acellular, and the only immunoglobulins present are those that are passively derived by diffusion from the systemic circulation. However, in pathological situations (i.e., demyelinating diseases, infections, and possibly even tumors) a local immune response occurs within the CNS and can result in the production of immunoglobulins. At present the detection of such local immune responses in CSF is predominately of diagnostic value only. However, these local CNS immune responses almost certainly play an important role in the pathogenesis of the diseases in which they occur.


Damaged goods: dilemmas of responsibility for risk.

The social and physical institutions of medical practice reflect society's acceptance of the physician's preeminent responsibility in determining the adequacy of health care. Such confidence evolved from historical circumstances--social and scientific--that changed concepts of susceptibility to disease. Twentieth century campaigns to control venereal disease exemplify the growing conflicts between political and professional control measures. The social and economic costs of resolving differential risks, needs, and resources are not likely to be accomplished easily and equitably.


Hydrocephalus and amenorrhea.

A 25-year-old woman was seen for the complaint of secondary amenorrhea. Skull roentgenograms revealed a markedly enlarged sella turcica. Studies of pituitary and hypothalamic function including prolactin were normal. A pneumoencephalogram revealed dilated ventricles and a mass in the septum pellucidum and hypothalamus. Partial removal of this hypothalamic astrocytoma and placement of an interventricular shunt resulted in the return of menses. Recurrent obstruction a few months later resulted in headache, disorientation, and amenorrhea. A shunt was placed again, resulting in clearing of symptoms and a reestablishment of normal menstrual cyclicity. It appears that the occurrence of increased intracranial pressure rather than the hypothalamic tumor caused the amenorrhea.


The blindness of Saint Paul.

The Book of Acts in the Bible relates the story of St Paul's sudden blindness and subsequent recovery of vision. St Paul was walking along when he saw a bright light; he fell down and awoke blind. He remained blind for three days, at which time his vision returned from a "laying on of hands." Numerous theories have been proposed to account for this event. A review of the available evidence suggests that there are six additional previously unreported possible causes, which are enumerated in detail.


Traumatic spondylolisthesis of the axis.

The lesions of C2 seen in hyperextension injuries of the cervical spine following motor vehicle accidents, diving accidents, and headlong falls resemble the cervical lesion found in judicial hangings. Although the mechanism of injury in these cervical fractures is different, the distinction is significant. The fracture seen in motor vehicular accidents today usually seems to be one of hyperextension and axial compression rather than hyperextension and distraction. This distinction is responsible for the low incidence of neurologic involvement seen in the fracture caused by motor vehicle accidents. The incidence of face and scalp injuries associated with axis pedicle fractures appears significant. Union of this fracture can generally be expected, and it rarely produces late sequelae. Management of this fracture is generally preferable on an ambulatory basis utilizing a cervicothoracic brace or a halo and caudal support in more unstable fractures. A period of 12 weeks of immobilization is recommended for satisfactory union of this fracture. Occasionally the treatment of this fracture may require traction or operative intervention. If operative intervention is required, an anterior route employing interbody fusion is suggested.


Chlorprothixene (taractan) in post-herpetic neuralgia and other severe chronic pains.

Two trials of chlorprothixene were carried out, mainly on patients with moderate to severe post-herpetic neuralgia. When the drug was given as 50 mg b.d. to outpatients, unpleasant side-effects were more important than slight effects in alleviating pain. When the drug was given as 50 mg 6 hourly to inpatients for 5 days only, there was alleviation of constant chronic pain in a third of the patients; the effect is still lasting over a period of months in a few patients. The side-effects during the course of treatment are prominent. It is concluded that the drug is worth trying in the course recommended by Farber and Burks [1] when other means of controlling postherpetic neuralgia have failed. It would be best to give the course only to inpatients.


The estimation of dermal collagen in osteoporotic patients by a histomorphometric method.

Sections of skin biopsies from the dorsum of the hand of patients with symptomatic osteoporosis were compared with those of carefully selected age-sex matched controls. The amount of dermal collagen in the osteoporotic individuals estimated by a histomorphometric method was found to be significantly less and severe degrees of collagen loss could be readily identified by microscopic examination. Distinct morphological abnormalities of the collagen fibres could also be observed in most patients with osteoporosis. This loss of dermal collagen is suggested to be the main factor responsible for the decrease in skin fold thickness and the frequently striking transparency of skin observed in association with osteoporosis.


Effects of relaxation training on cursive handwriting of fourth grade students.

A relaxation method of handwriting improvement was examined. The experimental and no-treatment control groups were composed of 10 students receiving a poor rating on handwriting characteristics and the normal control group of 10 was composed of students receiving average ratings. All three groups received nine trials of writing. Only the experimental group received relaxation training during each trial. The handwriting of the experimental group improved significantly while that of the no-treatment control group remained the same. Although the handwriting of the normal control group also improved significantly, at posttest they were no longer significantly different from the experimental group.


Machover revisited: impact of sex-role orientation on sex sequence on the draw-a-person test.

A significant relationship was obtained between sex of first figure drawn on the Draw-A-Person test and sex-role orientation, as operationalized by scores on the Bem Sex-role Inventory of 76 males and 93 female introductory psychology students. The most striking finding was that most of the women who drew the opposite-sex figure first were "feminine." To the extent that sex-role orientations can be empirically amalgamated with sex sequence, subsequent theory and research into clinical and diagnostic use of human figure drawings would increase in precision.


"It hurts red:" a preliminary study of children's perception of pain.

Children's perception of pain was investigated in an exploratory study. Some synaesthetic aspects were examined such as the color of pain, texture, shape, pattern and continuous vs intermittent quality. A projective test was developed using cartoons to illustrate two situations in which children commonly experience pain, a self-administered hammer blow and a doctor-administered needle. Interviews were tape-recorded with 58 children in hospital outpatient clinics and school situations in Kindergarten and Grades 1 through 3 in Licking County, Ohio. Significantly more children perceived the pain of a needle as jagged rather than smooth, and the pain of a hammer blow as a continuous rather than on-and-off pain. A finding of interest is the consistently greater differentiation in synaesthetic perception by the younger group on four of the five variables. Synaesthetic perception may be more characteristic of children in Piager's preoperational stage (aged 4-6); more cognitively oriented perception may be exhibited by 7- to 9-yr.-old children who approximate the stage of concrete operations.


Importance of imagery in maintenance of feedback-assisted relaxation over extinction trials.

Two groups of 16 female subjects undergoing frontalis EMG feedback training were identified according to whether they used imagery or passive concentration to achieve relaxation. The ability of these 2 groups to maintain relaxation during extinction sessions 2 and 7 days after termination of training was then investigated. Although both groups were equally successful in relaxing the frontalis during training, the group using imagery was significantly more successful in achieving relaxation during extinction sessions.


Qualitative differences in human figure drawings according to schizophrenic subtype.

Human figure drawings were obtained from 136 adult schizophrenics, of whom 63 were mentally retarded. The protocols were evaluated independently by three jduges for presence of 15 defined features that stressed the quality rather than specific content of the drawings. Adequate reliability and frequency were established for seven of the parameters, which were then compared for prevalence among subgroups classified by diagnosis, preognosis, chronicity, and level of retardation. Significant differences appeared for all comparisons and each of the analyzed features. The differences among non-retarded schizophrenic subgroups seemed to reflect phenomenological distinctions, while differences associated with intellectual retardation seemed to represent developmental limitations. These data supported the validity of the figure drawing technique for distinguishing among schizophrenic subtypes and underscored the importance of suitable methodology in evaluating projective measures.


[Computer-assisted 201Tl myocardial scintigraphy in the routine diagnosis of coronary heart disease (author's transl)].

The aim of the study was to evaluate the validity of 201Tl scanning for clinical routine use in the diagnosis of coronary heart disease. A computer-aided matrix with very high resolution displaying subtle color nuances was used. For semi-quantitative assessment a scale with 16 colors was applied. This permitted to differentiate between changes of intensity of 6.25%. Compared with the ECG on exercise no higher sensitivity or specifity of 201Tl scanning was found using coronary angiography as the reference method. When a typical angina pectoris and a pathological ECG on exercise was present, confirmation of the diagnosis of coronary heart disease by scanning was readily obtained. Moreover, in the event of equivocal findings in the ECG and of atypical chest pain scanning is helpful without having to resort to invasive methods. Additionally to the exercise ECG, the location of ischemic areas in the myocardium can be easily demonstrated by scanning. When angiography has shown unobstructed coronary arteries but the ECG is suggestive of scar formation, scintigraphy provides additional information regarding the diagnosis of coronary heart disease. It is also possible by scanning to delineate the tissue defect representing fibrotic areas. This is necessary for instance when aneurysmectomy is planned.


Acute infectious diarrhea in children.

Effective management of acute diarrheal disease depends on an understanding of the mechanisms and the pathogens responsible for diminished absorption of water from the intestines or increased secretion of water and electrolytes into the intestines. Initial therapy consists of fluid management, with hospitalization if dehydration is significant. Antibiotics are useful in treating specific disease entities, such as shigellosis. Careful attention to clinical status and follow-up is essential.


Investigation of macrocytic anemia.

The three most common causes of macrocytosis--vitamin B12 or folate deficiency, liver disease, and reticulocytosis--usually can be differentiated on the basis of red cell indexes and morphologic findings. Bone marrow studies are not indicated. In reticulocytosis, the mean corpuscular volume (MCV) rarely exceeds ll0 cu mu and a reticulocyte count quickly establishes the diagnosis. In liver disease, macrocytosis is also mild and uniform. The RBCs are round. In megaloblastic anemia, the MCV may exceed 150 cu mu. The RBCs vary considerably in size and shape. The macrocytes tend to be oval. Serum vitamin B12 determination remains the best test for unmasking vitamin B12 deficiency. It should be ordered in conjunction with serum and red cell folate determinations in the course of investigating a macrocytic anemia. When vitamin B12 deficiency has been established, a Schilling test or plasma uptake test is indicated to pinpoint the cause.


Diagnosis of rheumatic disease. 2. Laboratory tests.

Part 1, which begins on page 64, discusses diagnosis of rheumatic disease by radiography. The most popular laboratory tests in rheumatic disease are nonspecific and include those based on the formation of autoantibodies. Rheumatoid factor assays actually are of little diagnostic help in rheumatoid arthritis, but antinuclear antibody tests have become mandatory for identification of systemic lupus erythematosus. Studies based on immune complexes and cell immunity are valuable in specific clinical situations.


The physiological action of progesterone and the pharmacological effects of progestogens--a short review.

Substances described as progestogens differ greatly in their additional properties, which determine the limitations of their clinical use. The extrapolation of animal assays to human use requires caution, since synergism with oestrogens, which is usually necessary, shows widely-differing species-specific ratios. In other ratios, progestogens are often antagonistic to oestrogens.


Review of the status of oestrogen replacement therapy.

Oestrogen treatment of climacteric disorders, chiefly with formulations based on oestradiol or oestrone, which cause much less metabolic disturbance than synthetic oestrogens, is now widely accepted. Physiological replacement requires a blood production rate approaching 0.5 mg/day. Deleterious effects of oestrogen loss are known, but the appropriate scale of long-term prophylaxis with oestrogens is controversial. Evidence for a risk of endometrial carcinoma from unopposed oestrogen therapy is inconclusive but has focused attention on the concurrent use of progestogens, which is rising rapidly but is at present no more than 10%.


Experimental and clinical data indicating the psychotropic properties of progestogens.

Investigations of the psychotropic effects of progestogens employing the technique of quantitative pharmaco-EEG indicated that progestogens produce a profile similar to that of the minor tranquillizers. Healthy volunteers received single oral doses in a double-blind controlled study. A short review of the clinical literature adds support to the suggestion that progestogens have sedative properties.


Comparative trial of perhexiline maleate and oxprenolol in patients with angina pectoris.

A random single-blind study of oxprenolol against perhexiline has been undertaken in angina pectoris. Both drugs were effective in treatment (P less than 0.01) but perhexiline was better than oxprenolol (P less than 0.05), 12 of the 14 patients preferring perhexiline. Offset against this was the greater incidence of side effects with perhexiline, including one patient who later developed peripheral neuropathy. Despite the greater efficacy of perhexiline, it is suggested that side effects should preclude its routine prescription as a drug of first choice in angina pectoris. It should remain of value in the special situations of resistant angina and angina with heart failure or bronchospasm, when its use should be carefully monitored for these side effects.


[Interrelationship between the pineal gland and the hypothalamo-hypophyseal complex. IV. Effect of pinealectomy on the luteinizing function of the rat pituitary].

The effect of pinealectomy on the luteinizing function of the hypophysis was studied in sexually mature rats. Following pinealectomy or sham operation rats were blinded in one experimental series, and both blinded and ovariectomized--in another series. Blood LH was determined radioimmunologically with hard-phase immunosorbent produced from antiserum. Pinealectomy does not alter the basic blood LH concentration in the blinded male and female animals. In comparison with the sham operated rats, LH mobilization from the hypophysis was elevated in the blinded ovariectomized rats with removed pineal gland under the action of the maximal LH-releasing hormone dose (200 ng per rat). In comparison with the initial, the hormone concentration increased in control group by 189%, and in the pinealectomized--by 301%. Pinealectomy intensified the autopotentiating action of the LH-releasing hormone (in repeated administration in 60 min) to 1119%, whereas in control rats an increase of the blood LH in response to the repeated adminstration of the LH-releasing hormone constituted 730% in comparison with the initial level. Pinealectomy decreased the inhibitory action of actidion on the autopotentiating effect of the LH-releasing hormone. Besides, pinealectomy accelerated the I125-LH elimination from the circulation in the blinded female rats = 7 min). It is supposed that LH biosynthesis was more active in the hypophysis of pinealectomized rats.


[Biological properties of synthetic somatostatin].

Complex work on the assessment of biological properties of somatostatin synthesized according to a new original method was carried out. Its inhibitory action on the TTH, growth hormone and insulin secretion was demonstrated in vivo and in vitro. As a rule, somatostatin effect was expressed against the background of stimulated hormone secretion, although basal secretion inhibition was observed with respect to insulin, The inhibitory action of somatostatin on the hormonal secretion was direct, not mediated through any regulating factors.