Flauoprotein structure and mechanism 2. Monoamine oxidases: old friends hold many surprises

The two forms of monoamine oxidase (MAO), A and B, continue to be of major interest to biochemists, pharmacologists, neurologists, and gerontologists. Despite intensive study for more than half a century, unexpected and unique properties of these enzymes continue to come to light. Recent studies have centered on their kinetic mechanism, their unique predilection for substrates related to the neurotoxic tertiary amine MPTP, and their putative role in aging and in the etiology of neurodegenerative diseases. New and potent inhibitors of MAO A and MAO B continue to be developed because of their potential use in clinical medicine. Some are effective in the picomolar range but MAO B from different mammalian species shows remarkable differences in sensitivity to these agents.     

Closed rupture of the anterior tibial tendon. A case report

Closed subcutaneous rupture of the anterior tibial tendon is a relatively uncommon injury that requires a thorough clinical examination to diagnose correctly. The authors report a case of this disorder and provide a review of the relevant literature. A method of surgical repair not previously described in the literature is also presented.     

Overshadowing and latent inhibition counteract each other: support for the comparator hypothesis

In 4 conditioned lick suppression experiments with rats, the combined effects of latent inhibition treatment followed by overshadowing treatment were assessed as a test of the comparator hypothesis's (R.R. Miller & L.D. Matzel, 1988) explanations of overshadowing and latent inhibition. Experiments 1 and 2 confirmed the prediction of the comparator hypothesis that combined latent inhibition and overshadowing treatments attenuate the response deficit produced by either treatment alone. Furthermore, consistent with the comparator hypothesis, posttraining changes in the associative status of the putative comparator stimulus altered responding to the target conditioned stimulus (Experiment 3), and switching contexts between latent inhibition and overshadowing treatments (Experiment 4) eliminated the interaction between the latent inhibition and overshadowing treatments.     

Evaluation of possible population bias among high-dose atomic bomb survivors in the frequency of the HLA-DQA1 allele and DR antigen types

Many studies have suggested a relationship between certain alleles of the human leukocyte antigen (HLA) and the prevalence of some diseases or the immunological responsiveness to certain antigens. Furthermore, our studies in the past have demonstrated decreased immune function among atomic-bomb survivors who were exposed to high doses of radiation. However, no studies have addressed the possibility of various degrees of radiation-induced immune suppression being dependent on HLA type. To investigate the possibility of differing frequency distributions of HLA type in the Hiroshima atomic bomb survivors, HLA-DQA1 alleles and HLA-DR antigens were typed for 291 survivors in a high-dose group (>1.5 Gy), 339 survivors in an intermediate-dose group (0.005-1.5 Gy), and 388 in a distally exposed control group (<0.005 Gy). These doses are whole-body exposures, mainly from gamma-rays but with a small neutron component. When examinees were grouped by distinct pairs of HLA-DQA1 allele or HLA-DR antigen, no sex- or dose-related differences were found. However, when subjects were grouped by the presence of a specific allele or antigen, males carrying DQA1*0103 in at least one of their two HLA-DQA1 loci exhibited frequency distributions that decreased as radiation dose increased. These results suggest, although weakly, a possible population bias among male survivors with respect to HLA polymorphism. However, this bias is unlikely to be great enough to have a substantial effect on the cancer risk estimates.     

Picture perception and monocular vision: a reply to Hagen

It is argued that M. A. Hagen's (see record 1975-00215-001) review of picture perception contains a number of inaccuracies involving the nature of higher order variables in perception, the demonstration of visual compensation, the manipulation of relative size information, the postulation of an ability to discriminate the correctness of viewing point, and the existence of ambiguity in monocular perception. It is suggested that such errors are the result of a misunderstanding of the formal basis of J. J. Gibson's (1950, 1966) perceptual theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Process Failure Mechanisms and Optimal Design of Fraction Defective Control Charts

This note continues the study of various probability models for the duration of the process in the in-control state in the economic design of control charts. The fraction defective control chart is investigated, using both a discrete-time Markov model and two non-Markov models. Numericalexamples are presented which indicate that the process failure mechanism is an important consideration in optimum control chart design.     

Breast abscess associated with Helcococcus kunzii

Helcococcus kunzii, a nonvirulent member of the human skin flora, has recently been implicated in causing infections in immunosuppressed patients. We report a case of breast abscess associated with H. kunzii in an immunocompetant patient and discuss the criteria used in its identification and our observations of susceptibility testing for this species.     

Towards a standardized approach to DNA fingerprinting of Mycobacterium bovis. International Union Against Tuberculosis and Lung Disease, Tuberculosis in Animals Subsection

The Tuberculosis in Animals Subsection of the International Union Against Tuberculosis and Lung Disease (IUATLD) recently identified a need to standardize the deoxyribonucleic acid (DNA) strain typing of Mycobacterium bovis. The standard method for strain typing of M. tuberculosis isolates cannot be directly extrapolated to M. bovis due to the low copy number of IS6110 identified in the majority of M. bovis strains, particularly from cattle. To improve the resolution of M. bovis strains, alternative methods and additional DNA probes have been investigated. In combination with studies of published literature, laboratories performing M. bovis DNA fingerprinting were surveyed. Results of these surveys allowed us to reach consensus and to make recommendations for DNA typing of M. bovis isolates, which hopefully will lead towards a standardized approach to the DNA fingerprinting of this organism. This approach, in conjunction with conventional epidemiological traceback approaches, should facilitate more accurate and effective investigations into the epidemiology, maintenance and transmission of M. bovis within and between man and domesticated, feral and wild animals, both at a local and a global level.     

Effect of immediate and delayed post preparation on apical dye leakage using two different sealers

Eighty freshly extracted teeth were endodontically prepared and filled with gutta-percha and either a zinc oxide-eugenol-based sealer or AH26 to determine what effect these sealers, with widely differing properties, would have on apical microleakage after either immediate or delayed dowel space preparation. The teeth were randomly assigned to 1 of 4 groups, and the post space was made either immediately after filling or after being stored in 100% humidity for 1 wk. They were then immersed in a 2% methylene blue solution under vacuum, washed, and split longitudinally. The extent of dye penetration was read by five independent observers and the results analyzed. The only significant difference was in the delayed preparation group with zinc oxide-eugenol sealer, which showed greater leakage than the other groups.