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1.
Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication.  相似文献   
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Transmissible spongiform encephalopathy strains demonstrate specific prion characteristics, each with specific incubation times, and strain-specific patterns of deposition of the misfolded isoform of prion, PrPSc, in the brains of infected individuals. Different biochemical properties, including glycosylation profiles and the degree of proteinase resistance, have been shown to be strain-specific. However, no relationship between these properties and the phenotypic differences in the subsequent diseases has as yet been determined. Here we explore the utility of gene expression profiles to identify differences in the host response to different strains of prion agent. We identify 114 genes that exhibit significantly different levels of expression in mice infected with three strains of scrapie. These genes represent a pool of genes involved in a strain-specific response to prion disease. We have identified the most discriminatory genes from this list utilizing a wrapper-based feature selection algorithm with external cross-validation.  相似文献   
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Cephalochordates, the most basal extant group in the phylum Chordata, are represented chiefly by about 20 species of the genus Branchiostoma, commonly called amphioxus or lancelets. In recent years, insights into the evolutionary origin of the vertebrates have been gained from molecular genetic studies during the development of three of these amphioxus species (Branchiostoma floridae in North America, Branchiostoma lanceolatum in Europe, and Branchiostoma belcheri in East Asia). In spite of an estimated divergence time of 100-200 Myr among these species, all three are remarkably similar morphologically, and students of amphioxus have tacitly assumed that such resemblances arise during ontogeny from nearly identical networks of developmental genes. We felt that this assumption needed to be reexamined because instances are known--even in comparisons of closely related species--where characters seeming homologous on the basis of morphology actually develop under the control of conspicuously divergent genetic programs (a phenomenon termed "genetic piracy"). In the present work, we tested the hypothesis that morphological similarities reflect strict conservation of developmentally important genes' expression patterns in order to assess whether the developmental genetics of different amphioxus species show evidence of genetic piracy. To these ends, we cloned 18 genes implicated in different developmental functions in B. lanceolatum and compared their gene expression patterns with the known expression patterns of their orthologous genes in B. floridae. We show that, for the most part, conservation of gene expression parallels that of morphology in these two species. We also identified some differences in gene expression, likely reflecting experimental sensitivity, with the exception of Pax1/9, which may result from true developmental specificities in each amphioxus species. Our results demonstrate that morphological conservation reflects stasis in developmental gene expression patterns and find no evidence for genetic piracy. Thus, different species of amphioxus appear to be very similar, not only morphologically, but also in the genetic programs directing the development of their structural features. Moreover, we provide the first catalogue of gene expression data for the European species, B. lanceolatum.  相似文献   
6.
Treatment of patients diagnosed as schizophrenic with antipsychotic drugs (neuroleptics) is known to cause occasional unexplained depletion of white blood cells, especially neutrophil granulocytes. It has been known for many years that neuroleptics can interfere with the mitochondrial respiratory chain in vitro. Because there has been a growing interest recently in mitochondrial targeting of drugs, and since a quantitative structure-activity relationship (QSAR) model that predicts mitochondrial accumulation of neuroleptics has been published, we investigated the effects of neuroleptics on white blood cell mitochondria. Venous blood samples were collected from both patients undergoing treatment with neuroleptics and healthy volunteers. The samples were processed for transmission electron microscopy. The resulting images of white blood cells were analyzed using stereology to compare quantitatively mitochondrial morphology in the patient and control groups. We found that in patients, but not in controls, there was swelling of mitochondria and fragmentation of the mitochondrial cristae. There also were fewer mitochondria in patients than in controls, although due to the swelling of the organelles, the volume density of mitochondria in the two groups was not significantly different. Such changes are typical of a toxic insult. Consequently, it seems plausible that, since schizophrenia is not a disease considered to affect white blood cells per se, these changes probably are due to the medication.  相似文献   
7.
We previously described an enrichment-immunoassay utilizing a T6 monoclonal antibody capture enzyme-linked immunosorbent assay. Here we evaluated it for the rapid screening for Salmonella in fishmeal obtained from the national Animal and Plant Quarantine service in the People's Republic of China. In this method, the number of Salmonella present is first expanded by appropriate enrichment cultures, and the pathogens are then directly detected by the T6 immunoassay. In a total of 94 enrichment cultures of fishmeal, we obtained an overall concordance of 98% between the results obtained in parallel by this method and by conventional test method. The positive prediction by this method was 92% and the negative prediction was 100%. The turn around time for the new test was 27 h which is a significant improvement from the turn around time exceeding 96 h required for the conventional test method. This test proved to be compatible with the routine work flow in the practical setting of a quarantine laboratory.  相似文献   
8.
Fluorine‐based additives have a tremendously beneficial effect on the performance of lithium‐ion batteries, yet the origin of this phenomenon is unclear. This paper shows that the formation of a solid‐electrolyte interphase (SEI) on the anode surface in the first five charge/discharge cycles is affected by the stereochemistry of the electrolyte molecules on the anode surface starting at open‐circuit potential (OCP). This study shows an anode‐specific model system, the reduction of 1,2‐diethoxy ethane with lithium bis(trifluoromethane)sulfonimide, as a salt on an amorphous silicon anode, and compares the electrochemical response and SEI formation to its fluorinated version, bis(2,2,2‐trifluoroethoxy) ethane (BTFEOE), by sum frequency generation (SFG) vibrational spectroscopy under reaction conditions. The SFG results suggest that the ? CF3 end‐groups of the linear ether BTFEOE change their adsorption orientation on the a‐Si surface at OCP, leading to a better protective layer. Supporting evidence from ex situ scanning electron microscopy and X‐ray photoelectron spectroscopy depth profiling measurements shows that the fluorinated ether, BTFEOE, yields a smooth SEI on the a‐Si surface and enables lithium ions to intercalate deeper into the a‐Si bulk.  相似文献   
9.

Background  

Mannose binding lectin (MBL) is an important host defence protein against opportunistic fungal pathogens. This carbohydrate-binding protein, an opsonin and lectin pathway activator, binds through multiple lectin domains to the repeating sugar arrays displayed on the surface of a wide range of clinically relevant microbial species. We investigated the contribution of MBL to antifungal innate immunity towards C. parapsilosis in vitro.  相似文献   
10.
Biomedical spectroscopic experiments generate large volumes of data. For accurate, robust diagnostic tools the data must be analyzed for only a few characteristic observations per subject, and a large number of subjects must be studied. We describe here two of the current data analytic approaches applied to this problem: SIMCA (principal component analysis, partial least squares), and the statistical classification strategy (SCS). We demonstrate the application of the SCS by three examples of its use in analyzing 1H NMR spectra: screening for colon cancer, characterization of thyroid cancer, and distinguishing cancer from cholangitis in the biliary tract.  相似文献   
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