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During the course of a controlled comparison of thermal biofeedback and progressive muscle relaxation as treatments for essential hypertension three studies investigating the relationship of process variables to outcome were conducted. The three variables investigated were expectancies, skill acquisition, and home practice. For patients receiving progressive muscle relaxation, perceptions of deep relaxation during treatment sessions were most strongly related to outcome. For thermal biofeedback patients, expectancies and skill acquisition variables were both related to outcome. Frequency of home practice was related to successful outcome for both treatment groups.

The outer membrane proteins of Campylobacter fetus have been isolated by extraction of cell envelopes both in Triton X-100 and ethylenediaminetetraacetate (EDTA) and in sodium dodecyl sulfate (SDS). Each method yielded a major protein component, which migrated identically in SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and proved comparable in electrophoretic and molecular weight characteristics to the analagous protein from Escherichia coli. In addition, the surface of SDS-extracted C. fetus cells displayed a subunit structure similar to that observed in E. coli. The major envelope protein isolated with SDS appeared antigenically identical with one of the proteins isolated with Trition-EDTA on the basis of immunodiffusion reactions with specific antisera. Antibodies directed to the major envelope protein were not reactive in agglutination, immobilization, bactericidal, or opsonization reactions. Strains of C. fetus belonging to each of the three O serotypes possessed major envelope proteins comparable in SDS-PAGE but distinguished antigencally in a fashion paralleling the O serotype classification.

THIS paper outlines the distribution and management problems encountered in using 10 cm diameter PVC pipe for a 'sheet flow' vegetative-soil filter system for dairy liquid waste from a 70 cow dairy operation at Southern Illinois University, Carbondale, IL. Considerable emphasis is on the practical operation and layout but data included indicates the effectiveness of the system in reducing the pollution potential, as well as some effects on soil and plant growth. Rotation of ap-plication sites and proper maintenance of the system are essential for satisfactory operation.

This paper addresses itself to some comparisons of adaptive routing algorithms in store-and-forward Communication nets. The intent here is to demonstrate how some relatively simple add-ons to already existing adaptive algorithms can decrease the average message delay and increase message throughput in the network. The overview of many existing routing algorithms is intended to point out that, although an algorithm may be adaptive, it is not necessarily good in terms of the performance measures addressed in this paper. The basic objective of this study is to assess the effects of endogenous priority assignment to messages that have reached some specified aging threshold while in the network and to note the effects of Such priority assignment on network performance. The performance measures are average message delay, throughput, and number of messages undelivered. The routing techniques are demonstrated via simulation on an 8node highly connected network and a 19-node Advanced Research Projects Agency (ARPA) network. The routing algorithms are applied with and without network element destruction on the selected networks.

The contribution of "simple" intercalation and of adduct formation on the expression of frameshift mutations in Salmonella typhimurium was investigated using 9-aminoacridine and derivatives capable of either only intercalating between DNA base pairs or of forming adducts with DNA as well. For a chemical capable of intercalating as well as of forming an adduct, only a small portion of the frameshift mutagenicity is due to "simple" intercalation. Analogs only able to induce frameshift mutations as a result of intercalation generally display only a fraction (approx. 1%) of the frameshift activity of the analog capable of forming DNA adducts.

A glycoprotein responsible for the antiphagocytic properties of Campylobacter fetus has been identified by comparing cells of a wild-type strain with those of a mutant lacking this substance. The antiphagocytic component is demonstrable through electron microscopy as a discrete, negatively charged structure on the periphery of the cell. CLT is readily removed from the cell by mild extraction procedures and contributes to the inagglutinability in O antiserum normally displayed by C. fetus. Cells possessing this antigen are refractory to ingestion by macrophages except in the presence of specific antiserum. In its absence maximum phagocytosis occurs without a requirement for opsonins. It is concluded that the antiphagocytic component comprises a critical virulence factor of the bacterium.

Seventy-seven hypertensive patients, whose blood pressure [BP] on entry into the study was controlled on a regimen of two drugs (diuretic plus sympatholytic), participated in either progressive muscle relaxation or thermal biofeedback prior to attempting to discontinue the second stage drug. Although a discriminant function, containing 9 predictors, correctly classified 78% of short-term (6 weeks) successes and failures, no variables from standard psychological tests, several biochemical assays (plasma nor-epinephrine), or baseline home BPs entered the final equation. Overall, the value of prediction from the variables studied seems weak.

Through the routine use of cultures from saline slush transport solution and the initial and final organ perfusates, 14 of 81 cadaver allografts (17.3%) were found to have been contaminated before transplantation. Gram negative organisms, cultured from 5 of the 14 contaminated allografts, resulted in the recipient's death on the first encounter with this problem and the loss of two other allografts. Early antibiotic therapy begun even without evidence of overt infection appeared to prevent any further deaths or graft loss in those whose allografts were contaminated and yielded an overall survival comparable to that of uncontaminated allografts. Without such an approach to the study of perfused cadaver allografts and the management of them when found to be contaminated, this type of infection may go undetected and contribute to allograft and patient loss.

M-mode echocardiograms were obtained on unmedicated males with mild hypertension before and after treatment with thermal biofeedback, autogenic training, or self-relaxation. Although patients for whom diastolic blood pressure (DBP) was successfully reduced showed trends toward reduction in left ventricular parameters while unsuccessful patients showed no changes, the results were not significant. For the four patients with borderline left ventricular hypertrophy, there was a strong trend (p = .06) for successful treatment to lead to a reduction in left ventricular mass. Moreover, across the whole sample, reduction in left ventricular mass was related (r = .30) to decrease in DBP.

A derivative of Salmonella typhimurium TA98 which does not respond to the potent mutagenicity of 1,8-dinitropyrene is described. This novel strain also shows a lack of response to the mutagenic action of 1,3-dinitropyrene and a greatly reduced response to 1,6-dinitropyrene and 1-nitropyrene. The responses to 1,3,6-trinitropyrene and 1,3,6,8-tetranitropyrene are affected to a much lesser extent. This strain (TA98/1,8DNP6) is fully sensitive to the mutagenicity of 4-nitroquinoline-1-oxide, niridazole, nitroacridine, and nonnitrated frameshift mutagens. This strain appears to be deficient in a nitroreductase which reduces nitrated pyrenes and possibly other nitrated polycyclic aromatic hydrocarbons to corresponding hydroxylamines, the penultimate mutagens.

Salmonella typhimurium tester strain TA98/1,8-DNP6 is resistant to the mutagenicity of 1,8-dinitropyrene because it lacks an esterification enzyme which is needed for the formation of the ultimate mutagen, presumably the corresponding hydroxamic acid ester. This enzyme does not appear to be required for the activation of all nitroarenes and arylamines, as some of these are fully active in TA98/1,8-DNP. It is suggested that these form electrophilic arylnitrenium ions nonenzymatically from nitroso- and N-hydroxylamino-arenes intermediates. The esterification enzyme appears to be a transacetylase. An assay using 2-aminofluorene as the acetyl acceptor is described. Derivatives of S. typhimurium TA100 also lacking this enzyme were obtained by Tn5-mediated mutagenesis.

Ultrastructural examinations of the flagellum of Compylobacter (Vibrio) fetus were performed throughout the growth cycle. Filament diameters, exceeding 17.6 nm during the exponential phase, were substantially greater than those reported for unsheathed flagella of other genera with the exception of Pseudomonas fluorescens. Filament diameters increased during growth, reaching a mean width of 21.2 nm in middle to late stationary phase. Internal flagellar structure, principally of the parallel lined variety, was observed during the later periods of growth but not during exponential or early stationary phase. Despite the unusually large filament sizes, no evidence of a flagellar sheath was observed after selected treatments (0.01 N HCl, 6 M urea, tris(hydroxymethyl) amino-methane-hydrochloride buffer, warm water) or examination of thin sections. To determine whether alterations in filament size and variable ability to demonstrate filament fine structure were correlated with progressive changes in serological activity, agglutination and immobilization tests were conducted with antisera directed against intact flagella, the principal flagellar antigen, the O antigen, and a superficial glycoprotein which has been found in association with the flagellum and the cell envelope. Significant differences in the serological activity of cells at different growth intervals were not noted with any of the sera employed.

Several new concepts have been recently recognized as being increasingly important in water microbiology. Among these are included: 1) the difference disinfection resistance of bacteria exposed directly to the disinfectant as opposed those subcultured and then exposed, 2) the variation of population resistance disinfection in situ, 3) the interference with chloramine formation caused by natural aminoacids or polypeptides in eutrophic waters that decreases disinfection efficiency, and 4) the occurence of discrete events within the distribution system make it difficult to take representative samples. This paper presents data from our laboratory on each of the above subjects

Eighty-seven patients whose blood pressures (BPs) were controlled on a regimen of at least two antihypertensive medications were randomly assigned to either thermal biofeedback or progressive relaxation to see if patients could be withdrawn from the second-stage antihypertensive medication while BPs remained under control. Results on this clinical end point significantly favored thermal biofeedback both in the short-term (1-month posttreatment) and in the long-term (1-year posttreatment) with 35% of those patients who were initially assigned to thermal biofeedback and completed treatment remaining off the second-stage medication for over 12 months.

The excavations of seven archaeological sites on the island of Santa Cruz (Nendo), undertaken during the second phase of the Southeast Solomon Islands Culture History Program in 1977–78 are briefly summarized and the results discussed in terms of a local and regional culture historical framework. The local sequence, characterized by an earlier ceramic period and a later aceramic period, appears to have begun some 3000 years ago with a Western Lapita occupation, though there is also evidence for a coeval plain pottery complex that existed for a longer period of time. On present evidence the important ceramic to aceramic transition took place on Santa Cruz between c. 100 BC and AD 100. Only one site contains evidence of the early part of the aceramic period, which thus remains essentially unknown, including the matter of whether or not Santa Cruz was part of a posited regional exchange network in the first millenium AD. The latter part of the local sequence is represented in several sites from which important data were obtained relating to settlement and subsistence patterns, material culture and technology. including craft specialization, and ritual dance circles.

The fine structure of resting and germinating conidia ofPenicillium chrysogenum has been examined by electron microscopy. In addition to enlargement of the cells, a number of changes in ultrastructure become evident as morphogenesis proceeds. The newly synthesized germ tube is continuous with the corresponding layers of the conidial wall. Some conidial wall layers, however, do not extend into the hyphal wall. Several sections showing initial septum synthesis suggest that a septal pore is not a necessary structural entity. A characteristic orientation of the initial septum formed after germination is described. Aside from numerical considerations, no significant changes occur in nuclei, mitochondria, or ribosomes. The electron micrographs illustrate the presence of spherosomes, lomasomes, and nucleoli; the possible significance of these structures is discussed.

Drosophila affinis Sturtevant, D. quinaria Loew, D. putrida Sturt., D. robusta Sturt., D. tripunctata Loew, and D. immigrans Sturt. are the six native species most commonly encountered in north central Indiana, while D. melanogaster Meigen, D. hydei Sturt., and D. busckii Coquillett are introduced species which frequently attain large summer populations. Summer populations of the native species originate in deciduous woodlands, and during periods of population maxima in June the more prevalent species are widely dispersed through all of the major types of terrestrial habitats. Summer populations of the introduced species originate in proximity to human settlements and likewise disperse through a variety of habitats during periods of population increase, occurring with the native species in diverse situations in July but not achieving peak numbers until August. The species which infest tomatoes are widely, if thinly, dispersed at the time the crop ripens, and there is little expectation that preseason control efforts would be practicable. Despite disparate climatic conditions during the summers of 1958 and 1959, population developments in tomato fields were strikingly similar, thus indicating little correlation between normal weather extremes and population development. D. melanogaster is recognized as the principal species causing contamination of tomato products. Experimental evidence on comparative fecundity, developmental rates, and ovipositional behavior were obtained to explain the consistent prevalence of this species. Studies of diurnal activity and spatial distribution suggest that these facets of behavior are controlled principally by responses to atmospheric moisture. Adult flies were found to inhabit a space, only a few inches in height, directly above the soil surface. The micro environment provided by the foliage and fruit of the tomato plant does not require the insects to follow the pattern of peak activity at dawn and dusk often ascribed to Drosophila .

OUR present civilization differs from the civilizations of the past chiefly because of its larger mastery of the forces of nature. This is manifest in medicine, particularly in the greater control of light. The control of light permits the utilization of the microscope, the various endoscopic devices, and the roentgenologic apparatus. With these mechanisms for employing light, it is obvious that discovery of the method of control has preceded the medical application and that the degree of control has imposed boundaries beyond which medical usage can not pass. The development of roentgenology has been dependent upon the development of roentgenologic apparatus. The discovery itself came from the physical laboratory, and every roentgenogram is a silent tribute to the labors of von Guericke, the mayor of Magdeburg, who devised the air pump; to the Abbe Nollet, who passed electric discharges through partially exhausted globes; to Faraday and Geissler, and to the brilliant physicists of the latter part of the X...

A classical study of gas—solid surface interactions is reported. A two‐dimensional, independent oscillator lattice (IOL) is used as a surface model with harmonic potentials connecting each lattice site. Morse‐type potential functions are assumed to operate between the incident gaseous atom and each lattice atom. Using Monte Carlo techniques and numerical integration of the 16 differential equations describing the system, energy accommodation coefficients (EAC) and spatial distributions have been calculated for a (He/Ni) system. The dependence of these quantities upon incidence angle, gaseous beam temperature, surface temperature, and various interaction parameters has been investigated. The results indicate that the EAC increases with increasing beam temperature and beam velocity; decreases with increasing lattice force constant; increases with increasing attractive interaction between gas and surface; decreases with increasing incidence angle; and decreases as the surface and gaseous temperatures approac...

Absence of nephritogenic GBM antigen(s) in some patients with hereditary nephritis. The finding of a characteristic ultrastructural lesion in the glomerular basement membranes (GBM) of patients with hereditary nephritis prompted us to study and characterize the GBM alteration in patients with this condition. Both human anti-GBM sera from six patients with Goodpasture's syndrome and heterologous rabbit antihuman GBM sera were used as biological tools to evaluate the antigenic composition of GBM in kidneys from six patients representing five families with hereditary nephritis and sensorineural deafness. All six patients with hereditary nephritis demonstrated the characteristic GBM ultrastructural alteration described with this condition. The human anti-GBM sera, employed in an indirect immunofluorescence technique, localized on 20 control kidneys (normal and diseased) but failed to localize on GBM's of the six patients with hereditary nephritis. In contrast, the heterologous rabbit antihuman GBM antibody localized on all six kidneys from patients with hereditary nephritis as well as on control kidneys. A seventh patient with apparent hereditary nephritis and deafness received an allograft after developing renal failure. The patient subsequently developed circulating anti-GBM antibodies which localized in the allograft and reacted with the 20 control kidneys but not with his own kidney or with the kidneys of the other six patients with hereditary nephritis. The anti-GBM activity, demonstrated by indirect immunofluorescence and radioimmunoassay, could be absorbed from the human sera with a sonicated GBM preparation of normal kidney but not with an equivalent weight of GBM sonicate from an hereditary nephritis kidney. Absorption of the heterologous rabbit anti-GBM sera with normal kidney GBM sonicate abolished fixation on all control kidneys and on kidneys from patients with hereditary nephritis. However, absorption of the heterologous anti-GBM sera with GBM sonicate from a patient with hereditary nephritis abolished localization of the antisera on kidneys from patients with hereditary nephritis while localization on control kidneys was retained. Our study indicates that one group of patients with hereditary nephritis lacks an antigen(s) in the GBM which is present in normal kidneys. However, some antigen(s) in the GBM of patients with hereditary nephritis are shared with normal kidneys. The absent GBM antigen(s) in hereditary nephritis is related to the nephritogenic antigen most commonly observed in Goodpasture's syndrome. Absence d'antigene GBM nephritogene dans des familles de malades ayant une nephrite hereditaire. L'existence de lesions ultrastructurales caracteristiques dans la membrane basale glomerulaire (GBM) de certains malades ayant une nephrite hereditaire nous a conduits a etudier et a caracteriser la modification de la GBM chez les malades atteints de cette maladie. Nous avons utilise des serums humains anti-GBM provenant de six malades ayant un syndrome de Goodpasture, et des serums heterologues de lapin anti-GBM humaine comme outil biologique permettant d'evaluer la composition antigenique de la GBM de rein de malades correspondant a cinq familles ayant une nephrite hereditaire et une surdite neuro-sensorielle. Chez ces 6 malades atteints de nephrite hereditaire on trouvait l'alteration ultrastructurale de la GBM caracteristique decrite dans cette maladie. Les serums humains anti-GBM, utilises avec une technique d'immunofluorescence indirecte, etaient fixes sur 20 reins controles (normaux ou malades), mais ne se fixaient pas sur les GBM provenant des six malades ayant la nephrite hereditaire. En revanche, les anticorps heterologues de lapin anti-GBM humaine se fixaient sur les 6 reins des malades ayant une nephrite hereditaire, ainsi que sur les reins controles. Un septieme patient, avec une nephrite hereditaire probable et une surdite a ete greffe apres apparition d'une insuffisance renale. Chez ce patient sont ensuite apparus des anticorps anti-GBM circulants qui se fixaient sur le transplant, et qui reagissaient avec les 20 reins controles, mais non avec son propre rein malade ni avec les reins des 6 autres malades ayant une nephrite hereditaire. L'activite anti-GBM, mise en evidence par immunofluorescence indirecte et dosage radio-immunologique, pouvait etre absorbee des serums humains avec une preparation de GBM traitee par les ultra-sons, provenant de reins normaux, mais non avec un poids equivalent de GBM traitee par les ultra-sons, provenant de reins atteints de nephrite hereditaire. L'absorption des serums heterologues de lapins anti-GBM avec des GBM de rein normal supprimait la fixation sur tous les reins controles, ainsi que sur les reins provenant de malades ayant une nephrite hereditaire. Neanmoins, l'absorption de serums anti-GBM heterologues avec des GBM d'un patient ayant une nephrite hereditaire a supprime la fixation des anti-serums sur des reins de malades atteints de nephrite hereditaire alors que la fixation sur des reins controles persistait. Notre etude montre qu'un groupe de malades atteints de nephrite hereditaire manque d'un ou plusieurs antigenes de GBM presents dans les reins normaux. Cependant, certains antigenes de GBM de malades ayant une nephrite hereditaire sont communs avec ceux de reins normaux. Le(s) antigene(s) de GBM manquant(s) dans la nephrite hereditaire est relie a l'antigene nephritogene frequemment observe dans le syndrome de Goodpasture.

The gain or loss of a chromosome—or aneuploidy—acts as one of the major triggers for infertility and pregnancy loss in humans. These chromosomal abnormalities affect more than 40% of eggs in women at both ends of the age spectrum, that is, young girls as well as women of advancing maternal age. Recent studies in human oocytes and embryos using genomics, cytogenetics, and in silico modeling all provide new insight into the rates and potential genetic and cellular factors associated with aneuploidy at varying stages of development. Here, we review recent studies that are shedding light on potential molecular mechanisms of chromosome missegregation in oocytes and embryos across the entire female reproductive life span., Key Points What is known about this topic? Aneuploidy is a major cause of preclinical and prenatal fetal losses and congenital disorders in live born.Aneuploidy is highly dependent upon maternal age, especially advanced maternal age.Aneuploidy is predominantly from the mother. What does this study add? Aneuploidy originates from oocytes and preimplantation embryos.Aneuploidy follows a U curve with female age.New cellular and molecular mechanisms causing aneuploidies are discussed, including modelling approaches.

While halothane was without mutagenic activity in the Salmonella mutagenicity assay, even in the presence of microsomal fractions, the urines of anesthesiologists induced mutations of the base-substitution type.

A growing gap exists between U.S. Navy communications and Merchant Marine communications. As naval communications becomes more sophisticated, the capability of communications between U.S. Navy ships and U.S. Merchant Ships becomes reduced. Two systems have been developed to improve Merchant Ship communications. an imporved High Frequency System using digital selective calling and a Satellite Communication System. Brief technical descriptions of these systems are given to acquaint the “non—communicator” with these communications improvements.

Because of the unusually high reliability of short-term microbial assays for predicting the potential carcinogenicity of environmental agents, the emphasis of recent reports has been on standardization of experimental procedures, interlaboratory reproducibility, and the generation of a data base for a wide variety of chemicals (de Serres and Shelby, 1979a,b; Mattern et al., 1978; Seiler et al., 1980). Indeed, studies in this laboratory have dealt with experimental factors which may affect the mutagenic and genotoxic responses of potential carcinogens (Rosenkranz et al., 1976a,b, 1979a,b, 1980; Rosenkranz and Leifer, 1980; Rosenkranz and Poirier, 1979). All too often, however, we tend to forget that short-term assays can be used as research tools in the development of new concepts related to the molecular basis of DNA-adduct formation, its repair, and alternate mechanisms responsible for cancer Induction. In addition, the data base itself, if developed properly, may be an excellent source of information for the development of theoretical models which could form the basis of a more rational approach to risk evaluation.

The Ames test indicated that ampicillin (ABPC) and its novel ester KBT-1585 were non-mutagenic for any of the tester strains of Salmonella typhimurium TA 98, TA 100, TA 1535 and TA 1538, both in the presence and in the absence of rat liver microsomal activation mixtures. Diacetyl, the first metabolite of KBT-1585 by the in vitro hydrolysis proved to be non-mutagenic for a new tester strain TA 102 which is exquisitely sensitive to ketones and aldehydes.

Tris(2,3-dibromopropyl) phosphate, a widely used flame-retardant additive for textiles, is mutagenic to histidine-requiring strains of Salmonella typhimurium. Extracts of fabrics treated with this compound are also capable of inducing mutations in these bacterial strains.

There are several reasons which warrant a detailed and systematic study of the mutagenicity of aromatic nitro compounds in bacteria.

A young woman with progressive systemic sclerosis (PSS) and renal failure who received a renal transplant from her mother suffered accelerated loss of allograft function in the absence of hyperacute rejection or severe hypertension. A biopsy specimen and pathologic examination of the transplanted organ showed a fluorescent antibody pattern and vascular changes that were indistinguishable from those in the patient's native kidneys. This clinical sequence is a departure from the relative success of renal transplantation in the few previously reported cases of PSS where it has been used as therapy for renal failure.

In bacteria, 4-nitroquinoline-1-oxide (NQO) causes primarily mutations of the base-substitution type although frameshift mutations are also induced. The adducts formed are presumably recognized by error-prone DNA repair enzymes as evidenced by the much greater activity in plasmid pKM101-bearing taster strains. Although reduction of the nitro group appears to be required for mutagenic activity, this reduction is not catalyzed by the nitroreductase required for the demonstration of the mutagenicity in bacteria of other nitro-containing mutagens (nitrofurans, 2-nitronaphthalene, nitrofluorenes). The reduction of the nitro group appears to be catalyzed by a different nitroreductase. The mutagenicity of the non-carcinogenic 3-methyl-4-nitroquinoline-1-oxide (meNQO) may be related to this newly recognized nitroreductase. It is proposed, further, that the ultimate mutagenic intermediates derived from NQO and MeNQO differ.

Two major categories of membranoproliferative glomerulonephritis (MPGN) designated type 1 and 2 MPGN are currently recognized, largely on the basis of characteristic morphologic and immunofluorescence features. In contrast to experience reported from outside the United States, type 2 MPGN has been observed rather infrequently in this country. In a retrospective clinicopathologic study, 24 kidney specimens obtained from 10 children and young adults including seven females and three males (mean age: 13 years) with type 2 MPGN were identified using light, immunofluorescence, and electron microscopy. The histopathologic findings were related to the clinical course of each patient. When initially seen all patients had hematuria and proteinuria, three were nephrotic, and five were mildly hypertensive. A single patient was mildly azotemic. Eight patients had experienced an upper respiratory ifnection preceding their illness, although only one patient had evidence of a streptococcal pharyngitis. During a period of follow-up averaging 10 years, eight patients were nephrotic at some time during their illness and seven were persistently so. Hypertension was a major problem in eight patients and renal function declined markedly within a year of its onset in five. Persistence of the nephrotic syndrome from early onset of the disease, especially when associated with hypertension, was an additional sign of poor prognosis. Four patients developed chronic renal failure and three received one or more renal allografts. Histologic evidence of recurrent disease was found in allografts from the three patients as early as 7 months after transplantation in the absence of clinical features indicative of recurrent glomerulonephritis. It is concluded that type 2 MPGN is a chronic progressive renal disease of unknown etiology and pathogenesis which chiefly afflicts children and young adults. Hypertension and the early and persistent presence of the nephrotic syndrome suggest a poor prognosis. The disease appears to be largely unresponsive to conventional forms of therapy. The disease recurs with great frequency in allografts, often in the absence of clinical evidence of recurrent glomerulonephritis.

Nitrated polycyclic aromatic hydrocarbons, including carcinogens, may be non-mutagenic in microorganisms because bacterial nitroreductases are unable to reduce their nitro function to proximate mutagenic hydroxylamines. This reduction of the nitro moiety can be accomplished chemically in situ using zinc dust. The procedure, which is compatible with the Salmonella mutagenicity assay, was used to generate mutagens from chemicals which otherwise are non-mutagenic even in the presence of microsomal preparations.

Biochemical and microbiological studies were conducted to characterize the mechanism of bacterial formation of N-nitrosomorpholine from morpholine and nitrite at neutral pH. Nitrosating activity was markedly induced when bacteria were cultured anaerobically in minimal culture medium containing nitrate, while the presence of cysteine or tungsten in the medium inhibited induction. Of various metals, coenzymes and inhibitors tested for their effects on in vitro nitrosation of morpholine, potassium cyanide, sodium azide, NAD(P)H and nitrate strongly inhibited nitrosation. Several mutants of Escherichia coli A10 strain were prepared in order to examine whether nitrosation activity is linked to specific loci. Niridazole-resistant mutants, which lack nitroreductase, had as much nitrosating activity as the original E. coli A10, but chlorate-resistant mutants had completely lost this activity. A good correlation was observed between nitrate reductase activity and nitrosating activity in these mutants. These results indicate that bacterial nitrosation is an enzyme-mediated reaction closely associated with molybdenoenzymes such as the nitrate reductase/formate hydrogenlyase system.

We have conducted a cross-cultural (USA and USSR) comparison of thermal biofeedback (TBF) and autogenic training (AT) to a self-relaxation control condition in 59 unmedicated males with mild hypertension. Identical assessment and treatment protocols were carried out in both settings (Albany, New York, and Moscow). Treatments were delivered in small groups on an outpatient basis twice per week for 10 weeks. Results showed comparable, significant (p less than .05), short-term decreases (M = 8.5 mm Hg) in diastolic blood pressure (DBP) for both treatments at both sites. However, the Soviet patients, starting with significantly (p less than .01) higher systolic blood pressures (SBPs), showed significant decreases (M = 12.8 mm Hg) in SBP, whereas the American patients did not change appreciably (M = 4.6 mm Hg). During follow-up, the treated Soviet patients showed significantly (p less than .05) better maintenance of treatment effects, from 3 months to 1 year, than did the American patients. At 1 year, 75% of the treated Soviet patients had DBPs less than 90 mm Hg, whereas only 24% of the American patients had comparable DBPs.

The Ames test indicated that a novel beta-lactamase inhibitor YTR 830 H, belonging to penicillanic acid sulfone was non-mutagenic for any of the tester strains of Salmonella typhimurium TA 98, TA 100 and TA 102. The test was performed both in the presence and absence of S9 activation mixtures which were prepared from the livers of Aroclor 1254-induced Syrian hamsters.

The present study examined the psychological and psychophysiological dimensions of ‘office hypertension’. Forty hypertensive Ss were classified as Office Responders (n = 13), Nonresponders (n = 17) or Home Responders (n = 10) based on the observed discrepancies between home and office measures of BP. Psychological tests consisted of the SCL-90, Beck Depression Inventory, Spielberger Self-Analysis Questionnaire, State-Trait Anxiety Inventory, Buss-Durkee Hostility Inventory, Social Readjustment Rating Scale and Jenkins Activity Survey. Psychophysiological assessment consisted of constant monitoring and recording of BP during Baseline, Mental Arithmetic, Cold Pressor and Stressful Imagery conditions. Contrary to expectations, on psychological tests Office Responders did not differ from Nonresponders on measures of anxiety. However, Nonresponders were significantly higher than Office Responders on measures of anger and hostility, characteristics ascribed to the hypertensive personality. On psychophysiological assessment, Office Responders showed significantly greater increases in systolic BP than Nonresponders during a Mental Arithmetic task; however, the groups did not differ during a Cold-pressor task.

Microbial mutagenicity procedures are widely used as prescreens for the detection of environmental agents (10,11) endowed with genetic activity. Because of the remarkably good correlation between mutagenicity in bacteria and the potential for causing cancer in animals (13, 29, 30, 58, 59, 63, 76, 78, 91), these short-term assay procedures are also being used to identify potential environmental carcinogens. Our laboratory has participated in several studies dealing with the development, validation, and evaluation of a number of these short-term assay procedures which have included the following: the Salmonella (7), E. coli WP2 uvrA (17,42) and the multipurpose E. coli (66) mutagenicity assays, the host-mediated assay using Salmonella (51) the DNA repair-deficient E. coli (pol A+/pol A1 ‒) system (83,87), the Saccharomyces cerevisiae mitotic recombination assay (104), and the prophage λ inductest (67).

Cardiovascular reactivity (heart rate, systolic, and diastolic BP) to mental arithmetic and cold pressor were measured before and after treatment as part of the cross-cultural (USSR and USA) evaluation of thermal biofeedback and autogenic training (in comparison with self-relaxation) as treatments for mild hypertension in unmedicated males. There were no statistically reliable decreases in cardiovascular reactivity from before to after treatment. However, downward shifts in basal levels of systolic and diastolic BP at post-treatment led treated patients to have lower stress-induced levels of BP.

In the course of conducting a controlled comparison of progressive muscle relaxation and thermal biofeedback as possible substitutes for second-stage (sympatholytic) antihypertensive medications, we measured reactivity (heart rate, systolic blood pressure, and diastolic blood pressure) to three different stressors (mental arithmetic, cold pressor, and negative mental imagery) before and after treatment and drug withdrawal. Neither treatment was consistently effective in reducing reactivity across a variety of stressors. Relaxation led to more reductions in some aspect of reactivity than did biofeedback. The modest level of reductions in reactivity were seen more for mental arithmetic and systolic blood pressure.

There is little available evidence of the efficiency of preoperative screening for cancer in solitary thyroid nodules in the community hospital setting, and limited composite data for comparison. A three-year survey was made in a 480 bed community hospital to determine the percentage cancer index (PCI) found in patients operated on for solitary thyroid nodules. Cancer was diagnosed in ten of 153 patients with a PCI of 6.5%. For comparison, an extensive literature review revealed a mean PCI ranging from 13.8% to 27.9%, depending on the preoperative selection process. Periodic surveys of PCI in solitary nodules in community hospitals would yield pertinent information in relation to the general "state of the art" and encourage attainment of a PCI as high as feasible.