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91.
Alpha 2 adrenergic receptors are thought to play a crucial role in the etiology or treatment of mood disorders. Polymorphism(s) in the promoter region of the alpha 2 receptor may affect the gene expression and be associated with mood disorders. We studied the previously reported polymorphisms of the alpha 2A receptor gene at position-1291 in 114 healthy controls and 103 mood disorder patients. There was statistically no difference between controls and patients in either the genotype or the allele frequency. There was statistically no difference between the genotype and the clinical characteristics. Our results suggest there is no association between this polymorphism in the promoter region of the alpha 2A receptor gene and mood disorders.  相似文献   
92.
We have examined a series of 24 Merkel cell carcinoma (MCC) DNAs for loss of heterozygosity (LOH) at eight loci on chromosome 13. All patients were heterozygous for at least one locus. Overall, 18 of 24 (75%) patients showed LOH, among whom 10 patients demonstrated LOH at all informative loci. A single common region of loss was identified in all cases and included the marker D13S233 (13q14.3), which maps close to the retinoblastoma susceptibility gene RB1. The RB1 protein was not detected by Western blot analysis in any of nine MCC cell lines tested. These data indicate that 13q losses are the most common chromosomal losses observed to date in MCC and the likely target of these deletions is the RB1 locus.  相似文献   
93.
Controversy exists as to whether Kaposi's sarcoma-associated herpesvirus (KSHV) is more widespread than originally reported. Recently, Monini et al reported that KSHV is ubiquitous in urogenital and prostate tissues and sperm of healthy Italian adults using nested polymerase chain reaction (PCR). We have examined for the presence of KSHV in 10 normal prostates from Italian men and 10 from men from the United States, as well as 32 prostatic, 30 vulvar, 24 ovarian, 20 cervical, and 30 testicular cancer specimens from patients from the United States. None of the patients had a history of human immunodeficiency virus infection. The samples were tested by nested PCR. The sensitivity of this assay was determined by a dilution study performed by diluting KSHV DNA from the KS-1 cells (a primary effusion lymphoma cell line which is estimated to have 16 copies of KSHV per cell) in DNA from a K562 myeloid cell line. The nested PCR that we used can detect 2.4 copies of KSHV sequences on a background of K562 DNA. All the samples were negative for KSHV sequences. Therefore, we cannot confirm the finding that KSHV sequences are ubiquitous in urogenital and prostate tissues. Furthermore, because our samples were from both the United States and Italy, the discrepancy between results is unlikely to be explained by either ethnic or environmental factors. False-positive results easily occur using nested primer PCR because of contamination. Our data argue that KSHV is not widely disseminated in urogenital tissues from nonimmunosuppressed individuals.  相似文献   
94.
This study was undertaken to clarify whether or not binding to cyclophilin is a prerequisite for cyclosporin A-induced modulation of apoptotic cell death in eosinophils. Eosinophils were isolated from bronchoalveolar lavage fluid of mice challenged with inhaled allergen after sensitization. Apoptosis was determined by analysing the DNA content. At 72 h, 99% of the cells had died without addition of cytokines, whereas 55-60% of the cells survived in the presence of 10 U/ml recombinant murine interleukin 5 or recombinant murine granulocyte macrophage-colony stimulation factor (GM-CSF). Apoptotic cell death at 72 h in the presence of 10 U/ml interleukin 5 was increased by addition of cyclosporin H, an analogue of cyclosporin A without cyclophilin binding activity, in a concentration-dependent (0.3 to 3 microM) manner. The increase in apoptosis elicited by cyclosporin A and cyclosporin H took place also in the presence of 10 U/ml GM-CSF but to a lesser extent. There was a significant augmentation of apoptosis in eosinophils cultured in the presence of each cytokine for 72 h or longer. Tacrolimus (FK506) failed to augment apoptotic cell death. Thus, it is unlikely that binding of cyclosporin A to cyclophilin accounts for the increased apoptosis induced by cyclosporin A and its analogue in eosinophils. The increase in apoptosis induced by cyclosporin A, but not FK506, in activated eosinophils from the airways may be attributed to the anti-asthmatic effects of cyclosporin A.  相似文献   
95.
Three types of CeO2–ZrO2 (Ce:Zr=1:1 molar ratio) compounds with different oxygen storage/release capacities (OSCs) were characterized by means of the Ce K-edge and Zr K-edge X-ray absorption fine structure (XAFS). In order to investigate the relationship between the OSC and local structure, the quantitative EXAFS curve-fitting analysis was applied. By enhancing the homogeneity of the Ce and Zr atoms in the CeO2–ZrO2 solid solution, the OSC performance increased. Especially, the atomically homogeneous Ce0.5Zr0.5O2 solid solution exhibited the highest OSC among these CeO2–ZrO2 samples. Additionally, the local oxygen environment around Ce and Zr was remarkably modified by enhancing the homogeneity of the CeO2–ZrO2 solid solution. It was postulated that the enhancement of the homogeneity of the CeO2–ZrO2 solid solution and the modification of the oxygen environment would be the source for the OSC improvement.  相似文献   
96.
Spherical Si solar cell, which is made up of Si spheres with a diameter of approximately 1.0 mm, is expected to be a promising candidate for low consumption of Si feedstock and simple process technology. This paper describes the formation process and the structure of a concentrator module in detail. The concentrator lens was formed by casting with ultraviolet light hardening resin. The concentration ratio was 4.4 times and the pitch between the spheres was 2.0 mm. By this module design, it was possible to realize a consumption of the Si feedstock of about 3.0 g/W. Conversion efficiencies of 11.3% from single-sphere cell, 8.5% from a 23-spheres module and 5.2% from a 105-spheres module under AM1.5, 100 mW/cm2 illumination were achieved.  相似文献   
97.
Hepatocellular carcinoma (HCC) is one of the most common cancers in many parts of the world, however the molecular mechanisms underlying liver cell transformation remain obscure. A genome-wide scan of loss of heterozygosity (LOH) in tumors provides a powerful tool to search for genes involved in neoplastic processes. To identify recurrent genetic alterations in liver tumors, we examined DNAs isolated from 120 HCCs and their adjacent non tumorous parts for LOH using a collection of 195 microsatellite markers located roughly every 20 cM throughout 39 autosomal arms. The mean heterozygosity was 73%. Our findings provide additional support that LOH for loci on chromosomal arms 1p, 4q, 6q, 8p, 13q and 16p is significantly elevated in HCC. The highest percentage of LOH is found for a locus in 8p23 (42% of informative csaes). This corresponds to one of the most common genetic abnormalities reported to date in these tumors. In addition, high ratio of LOH (> or = 35%) is observed on chromosome arms which had not been implicated in previous studies, notably on 1q, 2q and 9q. No correlation was found between LOH of specific chromosomal regions and etiologic factors such as chronic infections with hepatitis B or C viruses. This first report of an extensive allelotypic analysis of HCC should help in identifying new genes whose loss of function contributes to the development of liver cancer.  相似文献   
98.
In the present study, we evaluated the potential of bradykinin (BK) to induce the release of neutrophil and monocyte chemotactic activity (NCA and MCA) and cytokines from an alveolar type II epithelial cell line, A549 cells. BK stimulated A549 cells to release NCA and MCA in a dose- and time-dependent manner (P < 0.001). Checkerboard analysis revealed that both NCA and MCA involved chemotactic and chemokinetic activity. Molecular sieve column chromatography showed three molecular weight masses (near 19 kd, 8 kd, and 400 d) for NCA and several molecular weight peaks (near 66 kd, 25 kd, 19 kd, 16 kd, and 400 d) for MCA. The release of NCA and MCA was inhibited by cycloheximide and lipoxygenase inhibitors (P < 0.01). The NCA and MCA were inhibited by leukotriene B4 (LTB4) receptor antagonist (P < 0.01), and the concentration of LTB4 was high enough for NCA and MCA. Antibodies to interleukin (IL)-8 and granulocyte colony-stimulating factor (G-CSF) attenuated NCA (P < 0.01), and antibodies to monocyte chemotactic protein-1 (MCP-1), G-CSF, and transforming growth factor (TGF)-beta attenuated MCA (P < 0.01). The levels of IL-8, G-CSF, MCP-1, and TGF-beta increased time dependently (P < 0.01). BK also stimulated the release of ILeukin-6 from A549 cells (P < 0.001). The receptors responsible for the release of NCA, MCA, and individual chemokines involved both BKB1 and BKB2 receptors. These data suggest that BK may stimulate alveolar type II pneumocytes to release inflammatory cytokines, which then may modulate the lung inflammation.  相似文献   
99.
Suppression of mitochondrial respiration and increased glycolysis are characteristic features of activated macrophages. We show here that antimycin A, a respiratory inhibitor, induced interleukin-1 synthesis and tumoricidal activity without inducing tumor necrosis factor or nitric oxide. The induction of tumoricidal activity was resistant to inhibitors of tyrosine-specific protein kinases and intracellular glycoprotein transport. The cognate interaction between macrophages and target cells was not a prerequisite for the tumoricidal activity. In contrast, lipopolysaccharide induced the production of interleukin-1, tumor necrosis factor and nitric oxide, the induction of tumoricidal activity being sensitive to genistein and brefeldin A. Antimycin A, like lipopolysaccharide, induced the release of a cytoplasmic enzyme and apoptosis of macrophages. Antimycin A showed anti-metastatic activity in vivo. These results suggest that the inhibition of oxidative respiration would induce apoptosis and the resultant release of soluble effector molecules of macrophages which inhibit tumor metastasis in vivo.  相似文献   
100.
Pneumocystis carinii is a human respiratory pathogen which causes fatal pneumonia in patients under immunosuppressed or immune deficient conditions. Recent work have documented the usefulness of the polymerase chain reaction (PCR) method in the detection of P. carinii from clinical samples. Therefore, we described our experience in using PCR method in the detection of P. carinii from respiratory samples. In our study, bronchial washing or BALF were good for diagnosis of P. carinii pneumonia (PCP) by PCR. However, PCR method in the detection of P. carinii from swab or sputum was too sensitive because small numbers of P. carinii organisms might be insignificant in causing the disease. It might reveal colonization or asymptomatic carrier state in the upper respiratory tract. Therefore, our result suggested that colonization or asymptomatic carrier state in the upper respiratory tract could eventually evolve into PCP. This would also facilitate basic progress in the pathology or epidemiology of P. carinii infection. In addition, an usefulness of prophylactic therapy for PCP was documented by PCR.  相似文献   
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