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991.
A 39-year-old woman presenting with microscopic hematuria was found to have an extensively calcified mass in the upper pole of the right kidney. Gross and histologic examination of the nephrectomy specimen revealed a 9.3-cm renal tumor composed of solid trabecular sheets of polygonal epithelial cells with clear cytoplasm and distinct cell borders characteristic of a chromophobe renal cell carcinoma. Electron microscopy showed the presence of numerous intracytoplasmic microvesicles, thereby confirming the diagnosis. However, the unique additional feature of this tumor included the presence of dense calcification and ossification throughout the tumor. To our knowledge, we report the first case of chromophobe renal cell carcinoma with the concomitant presence of extensive calcification and ossification. A literature review on chromophobe renal cell carcinoma with either calcification or ossification is performed.  相似文献   
992.
The development of new tuberculosis (TB) vaccines will require the identification of correlates of human protection. This study examined the balance between immunity and virulence in a whole blood infection model in which intracellular mycobacterial survival was measured using BACTEC. In the blood of tuberculin-negative donors, counts of Mycobacterium tuberculosis H37Ra organisms fell by 0.14 log10 CFU during 96 h of whole blood culture, whereas counts of Mycobacterium bovis BCG, M. tuberculosis H37Rv, and a clinical TB isolate's organisms increased by 0.13, 0.43, and 1.04 log10 CFU, respectively (P < 0.001), consistent with their relative virulence. Inhibition of tumor necrosis factor alpha by the addition of methylprednisolone or pentoxifylline or removal of CD4+ or CD8+ T cells by magnetic beads had deleterious effects on immune control of intracellular growth only in the blood of tuberculin-positive donors. Repeated vaccination of eight tuberculin-negative volunteers with M. bovis BCG resulted in a 0.3 log (50%) reduction in BCG CFU counts in the model compared to baseline values (P < 0.05). Three of the volunteers responded only after the second vaccination. These experiments indicate that whole blood culture may be used to measure immunity to M. tuberculosis and that further studies of repeated BCG vaccination are warranted.  相似文献   
993.
Mutations within microsatellite sequences, consisting of additions or deletions of repeat units, are known as the replication/repair error positive (RER +) phenotype or micorsatellite instability (MI). Microsatellite instability has been demonstrated in hereditary and sporadic colorectal carcinomas and is usually observed in noncoding regions of genomic DNA. However, relatively few coding region targets of MI have been identified thus far. Using PCR, we amplified regions encompassing (A)8 and (C)8 microsatellite tracts within hMSH3 and hMSH6 from 31 RER+ sporadic colorectal tumors, 8 hereditary colon cancers, 23 RER+ gastric carcinomas, and 32 RER- gastric tumors. Mutations were found in 11 (36%) of 31 sporadic colon carcinomas, 4 (50%) of 8 hereditary colorectal cancers, and 5 (22%) of 23 RER+ gastric carcinomas, but in only 2 (6%) of 32 RER-gastric carcinomas. These frameshift mutations cause premature stop codons downstream that are predicted to abolish normal protein function. Our results and those of others suggest that DNA mismatch repair genes, such as hMSH3 and hMSH6, are targets for the mutagenic activity of upstream mismatch repair gene mutations and that this enhanced genomic instability may accelerate the accumulation of mutations in RER+ tumors. Hum Mutat 10:474–478, 1997. © 1997 Wiley-Liss, Inc. This article is a US Government work, and, as such, is in the public domain in the United States of America.  相似文献   
994.

Objective

Breaking bad news (BBN) is a core component of medicine. Psychophysiological studies confirm the subjective reports of doctors that BBN is a stressful experience. This study investigated doctors’ physiological stress responses prior to and during two simulated bad news consultations.

Methods

Thirty-one doctors participated in a speech-interaction task and two simulated BBN consultations. Heart rate (HR) and skin conductance (SC) were recorded using consecutive 30-s epochs during each of the interactions. The simulations were video recorded.

Results

Most doctors showed an early anticipatory increase in HR and SC that peaked during the reading of the case history prior to the BBN consultations. Most doctors then experienced a brief and relatively small stress response. However, about one-third of the doctors showed a significant and sustained stress response.

Conclusions

The results suggest that most doctors were cognitively engaged with the BBN tasks, however, a small proportion of doctors might have focused more on their own internal feelings and less on these contextual features.

Practice implications

In regards to training medical students and doctors, these results suggest that there is a need to focus more on the impact of these encounters on the doctors, not just their performance during these encounters.  相似文献   
995.
Lyme disease is an infection caused by a tick-borne spirochete, Borrelia burgdorferi. Matrix metalloproteinase 9 (MMP-9) was selectively upregulated in the erythema migrans skin lesions of patients with acute Lyme disease. In this study, the mechanism of upregulation of MMP-9 was investigated in vitro and in vivo. The concentrations of MMP-9 and soluble CD14 were markedly elevated in serum from patients with acute Lyme disease and were also upregulated in U937 cells by B. burgdorferi in a time- and concentration-dependent manner. MMP-9 mRNA was expressed at baseline in fibroblasts in the presence or absence of B. burgdorferi. However, when fibroblasts were incubated with supernatants from U937 cells with B. burgdorferi or recombinant CD14, the expression of MMP-9 was significantly increased. This effect was completely abolished by the anti-CD14 antibody. These data suggest that the upregulation of MMP-9 by B. burgdorferi involves the CD14 pathway in infiltrating inflammatory cells. Fibroblasts could be recruited to amplify local production of MMP-9 by acquiring CD14 from macrophages.  相似文献   
996.
Acinetobacter baumannii has emerged as a major cause of both community-associated and nosocomial pneumonia, but little is known about the cellular and molecular mechanisms of host defense against respiratory infection with this bacterial pathogen. In this study, we examined the role of neutrophils in host resistance to pulmonary A. baumannii infection in a mouse model of intranasal (i.n.) infection. We found that neutrophils were rapidly recruited to the lungs following i.n. inoculation of the pathogen and declined to baseline level upon clearance of the infection. Depletion of neutrophils using monoclonal antibody RB6-8C5 prior to infection resulted in an acute lethal infection that was associated with enhanced bacterial burdens in the lung (P < 0.05) and extrapulmonary dissemination to the spleen. The increased susceptibility to A. baumannii in neutropenic mice was associated with a delay in the mRNA expression and production of early proinflammatory cytokines such as tumor necrosis factor alpha, interleukin-6, keratinocyte chemoattractant protein, monocyte chemoattractant protein 1, and macrophage inflammatory protein 2 (MIP-2) in the lungs and development of severe bronchopneumonia and lymphoid tissue destruction in the spleen. Moreover, i.n. administration of the neutrophil-inducing chemokine MIP-2 to normal mice induced a pulmonary influx of neutrophils and significantly enhanced the clearance of A. baumannii from the lungs (P < 0.01). These results imply that neutrophils play a critical role in host resistance to respiratory A. baumannii infection.  相似文献   
997.
998.
Nanopore sequencing has been investigated as a rapid and cost-efficient option for HLA typing in recent years. Despite the lower raw read accuracy, encouraging typing accuracy has been reported, and long reads from the platform offer additional benefits of the improved phasing of distant variants. The newly released R10.3 flow cells are expected to provide higher read-level accuracy than previous chemistries. We examined the performance of R10.3 flow cells on the MinION device in HLA typing after enrichment of target genes by multiplexed PCR. We also aimed to mimic a 1-day workflow with 8–24 samples per sequencing run. A diverse collection of 102 unique samples were typed for HLA-A, -B, -C, -DPA1, -DPB1, -DQA1, -DQB1, -DRB1, -DRB3/4/5 loci. The concordance rates at 2-field and 3-field resolutions were 99.5% (1836 alleles) and 99.3% (1710 alleles). We also report important quality metrics from these sequencing runs. Continued research and independent validations are warranted to increase the robustness of nanopore-based HLA typing for broad clinical application.  相似文献   
999.
The international literature on organ donation and transplantation has drawn attention to the popularity of “gift of life” discourse among pro-donation advocates, transplantation specialists, and within organisations lobbying for improved donation rates to promote the benefits of organ donation among members of the general public. In Aotearoa/New Zealand, gift of life discourse is robust. Aside from attempts to elicit altruism by promoting tissue donation in the public domain, gift terminology separates the act of donation from that of commerce and the commodification of body tissues. In distancing donation from commodification and the potential to degrade and exploit human beings, it is assumed that gift discourse transmits the positive message that donation is a noble and morally worthy act. Recent sociological research has shown that assumptions of the gift as one-way and altruistic do not necessarily align with people's perceptions and experience of donating body tissues, and that the vocabulary used to describe these acts is often at variance with reality. This article draws on interview data with 15 critical care specialists (intensivists) and donor and recipient coordinators, examining their perceptions of the relevance of gift discourse and its applicability in the context of deceased donation in Aotearoa/New Zealand. The data indicate several problems with gift rhetoric to describe the situations health professionals encounter. In sum, gift terminology tends to downplay the sacrifice involved in tissue donation generally, as well as depoliticising the exchange relations of tissue transfer in contemporary consumer culture and in the global context. This raises questions about the underlying ethics of language choice and what, if anything, empirical accounts of tissue transfer can contribute to ethical debates.  相似文献   
1000.
GVHD causes extensive morbidity and mortality in patients who receive alloHCT. Predictive and reliable markers for GVHD are currently lacking but required to improve the safety and accessibility of alloHCT. We present an experimental rat model of myeloablative total body irradiation and fully mismatched major and minor histoincompatible, T cell-depleted BMT, followed by delayed infusion of donor lymphocytes. This treatment, in contrast to marrow transplantation alone, resulted in severe aGVHD and 100% lethality within 2-6 weeks. We investigated the reconstitution kinetics and phenotypes of donor leukocyte subpopulations as well as the histopathology of selected organs that may correlate with GVHD, with the goal to find potential disease-related markers. We observed histological changes mainly confined to the skin, with degenerative changes in the basal layer. LNs and spleen showed deranged architecture with markedly increased accumulation of lymphocytes, whereas the gut, liver, and lungs appeared normal. Of the lymphocyte markers tested, donor-derived CD62L(+) T cells were markedly decreased in animals suffering from GVHD. Furthermore, we observed peripheral depletion of CD4(+)CD25(hi)FoxP3(+) T(reg), which was in contrast to controls. The relative frequency of these lymphocyte subpopulations in blood may therefore serve as accessible cellular markers of aGVHD. We propose that the animal model presented is instructive for the identification of clinically relevant markers of GVHD, which could improve disease diagnosis and management in alloHCT.  相似文献   
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