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171.
The human ETS family gene TEL2/ETV7 is highly homologous to TEL1/ETV6, a frequent target of chromosome translocations in human leukemia and specific solid tumors. Here we report that TEL2 augments the proliferation and survival of normal mouse B cells and dramatically accelerates lymphoma development in Emu-Myc transgenic mice. Nonetheless, inactivation of the p53 pathway was a hallmark of all TEL2/Emu-Myc lymphomas, indicating that TEL2 expression alone is insufficient to bypass this apoptotic checkpoint. Although TEL2 is infrequently up-regulated in human sporadic Burkitt's lymphoma, analysis of pediatric B-cell acute lymphocytic leukemia (B-ALL) samples showed increased coexpression of TEL2 and MYC and/or MYCN in over one-third of B-ALL patients. Therefore, TEL2 and MYC also appear to cooperate in provoking a cadre of human B-cell malignancies.  相似文献   
172.
The distinction between transudates and exudates   总被引:1,自引:0,他引:1  
Summary The first step in the diagnosis of pleural effusions is the distinction between exudates and transudates. The aim of this study was to evaluate the usefulness of various parameters for the differentiation of pleural exudates and transudates. We recorded clinical characteristics, final diagnoses, and measured pleural fluid and serum levels of albumin, protein, LDH, cholesterol, and bilirubin of 381 consecutive patients with pleural effusion. Seventy-one (23%) pleural effusions were transudates and 236 were exudates. As a single criterion, the pleural fluid to serum albumin ratio >0.5 was the most accurate parameter (88.4%). An albumin gradient of 12 g/l had an accuracy of 75% in the whole population but it detected 96% of transudative effusions in patients treated with diuretics. Light’s criteria and abbreviated Light’s criteria had similar accuracies, 87.8% vs. 88.2%, respectively. In conclusions, different alternatives can be used instead of Light’s criteria.  相似文献   
173.
174.
Platelet aggregation was measured by an optical method in 32 patients with iron-deficiency anemia at the time of diagnosis and after a period of supplementation with iron. Epinephrine- and adenosine diphosphate-induced platelet aggregation were lower in anemic patients than in the controls (p<0.05). After iron-supplementation therapy, these values showed no significant differences. If induced by collagen or ristocetin, platelet aggregation was the same for patients and controls, but increased after treatment of patients (p<0.05). The plasma zinc values did not show significant differences among the subjects included in this study. These results show that iron is involved in the enzymatic systems that regulate platelet aggregation. The exact nature of this interaction is still to be determined.  相似文献   
175.
XLalphas is a splice variant of the heterotrimeric G protein, Galpha(s), found on Golgi membranes in cells with regulated and constitutive secretion. We examined the role of the alternatively spliced amino terminus of XLalphas for Golgi targeting with the use of subcellular fractionation and fluorescence microscopy. XLalphas incorporated [(3)H]palmitate, and mutation of cysteines in a cysteine-rich region inhibited this incorporation and lessened membrane attachment. Deletion of a proline-rich region abolished Golgi localization of XLalphas without changing its membrane attachment. The proline-rich and cysteine-rich regions together were sufficient to target the green fluorescent protein, a cytosolic protein, to Golgi membranes. The membrane attachment and Golgi targeting of the fusion protein required the putative palmitoylation sites, the cysteine residues in the cysteine-rich region. Several peripheral membrane proteins found at the Golgi have proline-rich regions, including a Galpha(i2) splice variant, dynamin II, betaIII spectrin, comitin, and a Golgi SNARE, GS32. Our results suggest that proline-rich regions can be a Golgi-targeting signal for G protein alpha subunits and possibly for other peripheral membrane proteins as well.  相似文献   
176.
The testis-determining gene SRY is not well-conserved among mammals, particularly between mouse and other mammals, both in terms of protein structure and of expression regulation. To evaluate SRY phylogenic conservation in regards to its function, we expressed the goat gene (gSRY) in XX transgenic mouse gonads. Here, we show that gSRY induces testis formation, despite a goat expression profile. Our results demonstrate that sex-reversal can be induced in XX-mice by a non-mouse SRY thus suggesting a conserved molecular mechanism of action of this testis-determining gene across mammalian species.  相似文献   
177.
Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in serotonin biosynthesis. A novel gene, termed TPH2, has recently been described. This gene is preferentially expressed in the central nervous system, while the original TPH1 is the peripheral gene. We have expressed human tryptophan hydroxylase 2 (hTPH2) and two deletion mutants (NDelta150 and NDelta150/CDelta24) using isopropyl beta-D-thiogalactopyranoside-free autoinduction in Escherichia coli. This expression system produced active wild type TPH2 with relatively low solubility. The solubility was increased for mutants lacking the NH(2)-terminal regulatory domain. The solubility of hTPH2, NDelta150, and NDelta150/CDelta24 are 6.9, 62, and 97.5%, respectively. Removal of the regulatory domain also produced a more than 6-fold increase in enzyme stability (t((1/2)) at 37 degrees C). The wild type hTPH2, like other members of the aromatic amino acid hydroxylase superfamily, exists as a homotetramer (236 kDa on size exclusion chromatography). Similarly, NDelta150 also migrates as a tetramer (168 kDa). In contrast, removal of the NH(2)-terminal domain and the COOH-terminal, putative leucine zipper tetramerization domain produces monomeric enzyme (39 kDa). Interestingly, removal of the NH(2)-terminal regulatory domain did not affect the Michaelis constants for either substrate but did increase V(max) values. These data identify the NH(2)-terminal regulatory domain as the source of hTPH2 instability and reduced solubility.  相似文献   
178.
Apitherapy or therapy with bee products as honey is an old tradition. In this study, the antimicrobial activity of 84 honey samples were investigated against 8 bacteria potential pathogens and 2 fungi. Honey samples were obtained from 10 different floral sources. The findings indicate that honey samples with thyme, thyme + acorn, pine + carob, pine + carob + anis and pine + chestnut are more effective than the other honey of floral sources. The results of the survey show that most of honey samples at 50% (w/v) can completely inhibit the growth of all of the tested bacteria. The fungi were less sensitive than the bacteria to the antimicrobial activity of honey. The sensitivity of microorganisms to sugar solutions with similar sugar contents as some honey samples which have high antimicrobial activity were also assayed. This sugar solutions inhibited a narrow range of bacteria and did not inhibit any of the fungi tested. In conclusion, these results encourage further studies to investigate possible benefits of the use of honey among therapies in the treatment of bacterial infections.  相似文献   
179.
Although the use of chemical pesticides has decreased in recent years, it is still a common method of pest control. However, chemical use leads to challenging problems. The harm caused by these chemicals and the length of time that they will remain in the environment is of great concern to the future and safety of humans. Therefore, developing new pest control agents that are safer and environmentally compatible, as well as assuring their widespread use is important. Entomopathogenic agents are microorganisms that play an important role in the biological control of pest insects and are eco-friendly alternatives to chemical control. They consist of viruses (non-cellular organisms), bacteria (prokaryotic organisms), fungi and protists (eukaryotic organisms), and nematodes (multicellular organisms). Genetic modification (recombinant technology) provides potential new methods for developing entomopathogens to manage pests. In this review, we focus on the important roles of recombinant entomopathogens in terms of pest insect control, placing them into perspective with other views to discuss, examine and evaluate the use of entomopathogenic agents in biological control.  相似文献   
180.
Robust and sensitive ELISPOT protocols are commonly applied concomitant with the development of new immunotherapeutics. Despite the knowledge that individual serum batches differ in their composition and may change properties over time, serum is still commonly used in immunologic assays. Commercially available serum batches are expensive, limited in quantity and need to be pretested for suitability in immunologic assays, which is a laborious process. The aim of this study was to test whether serum-free freezing media can lead to high cell viability and favorable performance across multiple ELISPOT assay protocols. Thirty-one laboratories from ten countries participated in a proficiency panel organized by the Cancer Immunotherapy Immunoguiding Program to test the influence of different freezing media on cell quality and immunologic function. Each center received peripheral blood mononuclear cells which were frozen in three different media. The participants were asked to quantify antigen-specific CD8+ T-cell responses against model antigens using their locally established IFN-gamma ELISPOT protocols. Self-made and commercially available serum-free freezing media led to higher cell viability and similar cell recovery after thawing and resting compared to freezing media supplemented with human serum. Furthermore, the test performance as determined by (1) background spot production, (2) replicate variation, (3) frequency of detected antigen-specific spots and (4) response detection rate was similar for serum and serum-free conditions. We conclude that defined and accessible serum-free freezing media should be recommended for freezing cells stored for subsequent ELISPOT analysis.  相似文献   
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