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991.
992.
The clinical characteristics of Pneumocystis jirovecii pneumonia (PCP) in patients with immunodeficiency virus (HIV) infection (HIV-PCP) differ from those in patients without HIV infection (non-HIV-PCP). We analyzed 31 adult HIV-PCP cases and 44 non-HIV-PCP cases between 2008 and 2018. The symptomatic period before the diagnosis was shorter in non-HIV-PCP (5 [3–8] days vs. 29 [14–55] days, P < 0.001) and the overall survival rate was lower in the non-HIV-PCP group (P = 0.022). Serum β-D glucan positivity (72.7% vs. 93.5%, P = 0.034) and Grocott stain positivity for Pneumocystis jirovecii in the bronchoalveolar lavage fluid (4.3% vs. 73.3%, P < 0.001) were significantly lower in the non-HIV-PCP group. This difficulty in laboratory diagnosis possibly resulted in the administration of concurrent antibiotics such as quinolones and macrolides (56.8% vs. 19.4% P = 0.002) in the non-HIV-PCP group. The adverse effects due to trimethoprim-sulfamethoxazole were more frequently observed in HIV-PCP (86.2% vs. 35.3%, P < 0.001). The duration of discontinuation of trimethoprim-sulfamethoxazole was 11 [8–14.5] days in HIV-PCP cases. Co-administration of adjunctive corticosteroid therapy did not mitigate hypersensitivity to trimethoprim-sulfamethoxazole. Our analysis indicated that the characteristics of PCP in patients with or without HIV was quite different. HIV-positive patients with PCP should be monitored closely to avoid adverse effects due to trimethoprim-sulfamethoxazole. Because positivity polymerase chain reaction test for P. jirovecii remained high (91.7%), it is suggested that bronchofiberscopy is warranted for diagnosis of PCP in HIV-negative patients.  相似文献   
993.
A new combined test, accelerated exercise following mild hyperventilation (HV), was examined to determine whether it is effective at detecting a positive response in patients with pharmacologically-induced coronary vasospasm and near normal coronary arteries. Fifty-eight consecutive patients who underwent both triple non-invasive spasm provocation tests and diagnostic coronary angiography were enrolled. They all had pharmacologically-induced coronary vasospasms and no significant organic stenosis. In these patients, an HV test was performed first, followed by a treadmill exercise test (TET), and finally the new combined test under no medication within 3 days. Of the 58 patients, positive responses were observed in 9 patients to the HV, in 15 to the TET, and in 35 to the newly combined test. The remaining 21 patients had negative responses although the triple sequential tests were perfomed. Thus, the sensitivities of the HV test, TET, and newly combined test were 16% (9/58), 26% (15/58), and 63% (35/56), respectively. Forty-six subjects with near normal coronary arteries and no ACh-provoked spasm served as controls. None of these subjects had positive responses to any of these three tests, and thus their specificity was all 100%. No serious or irreversible complications were seen in this study. We recommend this newly-combined protocol for the induction of coronary artery spasm in patients with vasospastic angina pectoris and without significant stenosis as a diagnostic tool.  相似文献   
994.
OBJECTIVES: Staphylococcus aureus with low-level resistance to vancomycin (VLSA) which could develop into vancomycin-resistant S. aureus (VRSA) is most important. However, VLSA is difficult to detect by standard laboratory methods. We describe here improved methods to detect VLSA. METHODS: Three methicillin-resistant S. aureus (MRSA) strains, designated Fu6, Fu10, and Fu18, were sequentially isolated from the burn wound site of a patient, during vancomycin therapy. The properties of these strains were compared with those of reference strains Mu3 and Mu50 (previous resistant isolates from other patients). RESULTS: The isolated strains, Fu10 and Fu18, had identical phenotypes and genotypes. The vancomycin resistance of Fu10 was equivalent to that of strain Mu3, whereas Fu18 had much higher vancomycin resistance than Fu10 and Mu3, although reaching the level of Mu50. Fu18 showed similar growth to Mu50 on gradient gels and on Mu3 medium. CONCLUSIONS: Our data indicate that the VLSA developed vancomycin resistance during exposure to vancomycin in vivo. The population analysis of tested VLSA and vancomycin intermediately resistant S. aureus (VISA) indicates that a penem at relatively low concentrations induced a significant increase in the number of vancomycin-resistant subpopulations. Furthermore, we confirmed that gradient gel analysis and Mu3 medium are simple and useful methods for the detection of VLSA judged as VSSA by its conventional MIC alone.  相似文献   
995.
Despite their high degree of genomic similarity, reminiscent of their relatively recent separation from each other ( approximately 6 million years ago), the molecular basis of traits unique to humans vs. their closest relative, the chimpanzee, is largely unknown. This report describes a large-scale single-contig comparison between human and chimpanzee genomes via the sequence analysis of almost one-half of the immunologically critical MHC. This 1,750,601-bp stretch of DNA, which encompasses the entire class I along with the telomeric part of the MHC class III regions, corresponds to an orthologous 1,870,955 bp of the human HLA region. Sequence analysis confirms the existence of a high degree of sequence similarity between the two species. However, and importantly, this 98.6% sequence identity drops to only 86.7% taking into account the multiple insertions/deletions (indels) dispersed throughout the region. This is functionally exemplified by a large deletion of 95 kb between the virtual locations of human MICA and MICB genes, which results in a single hybrid chimpanzee MIC gene, in a segment of the MHC genetically linked to species-specific handling of several viral infections (HIV/SIV, hepatitis B and C) as well as susceptibility to various autoimmune diseases. Finally, if generalized, these data suggest that evolution may have used the mechanistically more drastic indels instead of the more subtle single-nucleotide substitutions for shaping the recently emerged primate species.  相似文献   
996.
BACKGROUND AND AIM: In order to evaluate loss of the p53 gene more precisely, we performed dual-color fluorescence in situ hybridization (dual-color FISH) for chromosome 17 and p53 gene together with DNA polymorphism analysis of the p53 gene in hepatocellular carcinoma (HCC). METHODS: Dual-color FISH using probes specific for the centromere of chromosome 17 and the p53 gene was performed for 41 HCC and DNA polymorphism analysis was also performed for them. RESULTS: Of the 34 HCC tested by dual-color FISH, 20 had loss of at least one p53 gene (58.8%). In contrast, of the 32 HCC tested by DNA polymorphism analysis, 23 gave informative results, among which only eight had loss of heterozygosity (LOH) of the p53 gene (34.8%). Notably, among 14 cases positive for loss of the p53 gene by dual-color FISH, seven cases were negative for LOH of the p53 gene. Moreover, dual-color FISH revealed that the percentage of cells that lost at least one p53 gene increased as the HCC became less differentiated (P < 0.01), whereas LOH did not reveal any such correlation. CONCLUSIONS: These data suggest that loss of the p53 gene was present in a considerable number of HCC, and diversity of the p53 gene aberration increases with progression of HCC. Dual-color FISH is an effective method for detection of p53 gene aberration, and it can provide new insight into oncogenesis in HCC.  相似文献   
997.
BACKGROUND: With increasing use of EMR for early stage esophageal carcinoma, the number of cases of iatrogenic esophageal perforation is likely to increase. This study evaluated the results of endoscopic clip application for treatment of perforations caused by EMR in patients with esophageal carcinoma. METHODS: Among 185 patients who underwent EMR for esophageal carcinoma, esophageal perforation occurred in 3 patients (1.6%). Metallic clips were immediately applied endoscopically to close the perforations. OBSERVATIONS: All 3 patients were observed closely and were managed conservatively (intravenous hyperalimentation, antibiotics) after closure of the perforation. They were discharged without any further serious complication. CONCLUSIONS: When esophageal perforation caused by EMR is immediately recognized, endoscopic application of metallic clips is appropriate therapy. However, patients must be carefully monitored for the development of generalized mediastinitis.  相似文献   
998.
Apheresis has been recognized both economically and therapeutically as a novel approach for the treatment of inflammatory diseases, and certain others, which respond poorly to drug therapy. This report is about Adacolumn, an adsorptive carrier based granulocyte and monocyte apheresis device with a volume of 335 mL, filled with about 220 g of cellulose acetate beads of 2 mm diameter as the column adsorptive carriers. Pre- and post-column leukocyte counts have shown that the carriers adsorb about 65% of granulocytes, 55% of monocytes and 2% of lymphocytes from the blood in the column. Additionally, after apheresis, there is a marked decrease in inflammatory cytokines (TNF-alpha, IL-1beta, IL-6 and IL-8) produced by blood leukocytes, together with down-modulation of L-selectin and the chemokine receptor CXCR3. Adacolumn has been used to treat patients with rheumatoid arthritis, ulcerative colitis and HIV infection. Typical apheresis sessions have been 4-10, at a frequency of one or two sessions per week. Treatment of patients with Adacolumn has been associated with very promising efficacy and safety data. Accordingly, in Japan, Adacolumn has been approved by the Ministry of Health for the treatment of ulcerative colitia. Furthermore, Adacolumn met the required quality and safety standards for medical devices and received an EC certification (CE-mark) from TUV in 1999. However, although Adacolumn carriers are very efficient in depleting excess and activated granulocytes and monocytes/macrophages, the clinical efficacy associated with Adacolumn apheresis cannot be fully explained on the basis of reducing granulocytes and monocytes per se. Hence, a long lasting effect on inflammatory cytokine generation, chemokine activities or immunomodulation is likely, but the precise mechanisms involved are not fully understood yet.  相似文献   
999.
Received: January 9, 2001 / Accepted: May 11, 2001  相似文献   
1000.
Osteoclasts, bone-resorptive multinucleated cells derived from hematopoietic stem cells, are associated with many bone-related diseases, such as osteoporosis. Osteoclast-targeting small-molecule inhibitors are valuable tools for studying osteoclast biology and for developing antiresorptive agents. Here, we have discovered that methyl-gerfelin (M-GFN), the methyl ester of the natural product gerfelin, suppresses osteoclastogenesis. By using M-GFN-immobilized beads, glyoxalase I (GLO1) was identified as an M-GFN-binding protein. GLO1 knockdown and treatment with an established GLO1 inhibitor in osteoclast progenitor cells interfered with osteoclast generation, suggesting that GLO1 activity is required for osteoclastogenesis. In cells, GLO1 plays a critical role in the detoxification of 2-oxoaldehydes, such as methylglyoxal. M-GFN inhibited the enzymatic activity of GLO1 in vitro and in situ. Furthermore, the cocrystal structure of the GLO1/M-GFN complex revealed the binding mode of M-GFN at the active site of GLO1. These results suggest that M-GFN targets GLO1, resulting in the inhibition of osteoclastogenesis.  相似文献   
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