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91.
Shieh WJ Hsiao CH Paddock CD Guarner J Goldsmith CS Tatti K Packard M Mueller L Wu MZ Rollin P Su IJ Zaki SR 《Human pathology》2005,36(3):303-309
This article describes the pathological studies of fatal severe acute respiratory syndrome (SARS) in a 73-year-old man during an outbreak of SARS in Taiwan, 2003. Eight days before onset of symptoms, he visited a municipal hospital that was later identified as the epicenter of a large outbreak of SARS. On admission to National Taiwan University Hospital in Taipei, the patient experienced chest tightness, progressive dyspnea, and low-grade fever. His condition rapidly deteriorated with increasing respiratory difficulty, and he died 7 days after admission. The most prominent histopathologic finding was diffuse alveolar damage of the lung. Immunohistochemical and in situ hybridization assays demonstrated evidence of SARS-associated coronavirus (SARS-CoV) infection in various respiratory epithelial cells, predominantly type II pneumocytes, and in alveolar macrophages in the lung. Electron microscopic examination also revealed coronavirus particles in the pneumocytes, and their identity was confirmed as SARS-CoV by immunogold labeling electron microscopy. This report is the first to describe the cellular localization of SARS-CoV in human lung tissue by using a combination of immunohistochemistry, double-stain immunohistochemistry, in situ hybridization, electron microscopy, and immunogold labeling electron microscopy. These techniques represent valuable laboratory diagnostic modalities and provide insights into the pathogenesis of this emerging infection. 相似文献
92.
Plachot Michelle; Junca Anne-Marie; Mandelbaum Jacqueline; Cohen Jean; Salat-Baroux Jacques; Lage C.Da 《Human reproduction (Oxford, England)》1986,1(4):237-242
In humans, in contrast to other species, sperm capacitationrequires a very short time, as in-vitro fertilization has beenobtained after only 45 mm of contact between oocytes and spermatozoacapacitated for 1 h. No fertilization occurred, whatever theduration of sperm capacit.ation, when gamete mixing did notexceed 30 mim. On the contrary, 85% of cumulus-free mature oocytesexposed to sperm for 14 h were fertilized. The presenceof the pre-ovulatory, fully-expanded or compact cumulus massdid not represent a physical barrier to sperm progression, aswe observed no delay in fertilization when oocytes were enclosedin the cumulus. The use of a short insemination protocol (14h instead of 1720 h) did not reduce the fertilizationrate of denuded or cumulus-enclosed oocytes and had no significanteffect on the morphological appearance of the embryos or theircleavage rates. 相似文献
93.
Adenoviral vectors expressing siRNAs for discovery and validation of gene function 总被引:5,自引:0,他引:5 下载免费PDF全文
Arts GJ Langemeijer E Tissingh R Ma L Pavliska H Dokic K Dooijes R Mesić E Clasen R Michiels F van der Schueren J Lambrecht M Herman S Brys R Thys K Hoffmann M Tomme P van Es H 《Genome research》2003,13(10):2325-2332
RNA interference is a powerful tool for studying gene function and for drug target discovery in diverse organisms and cell types. In mammalian systems, small interfering RNAs (siRNAs), or DNA plasmids expressing these siRNAs, have been used to down-modulate gene expression. However, inefficient transfection protocols, in particular, for primary cell types, have hampered the use of these tools in disease-relevant cellular assays. To be able to use this technology for genome-wide function screening, a more robust transduction protocol, resulting in a longer duration of the knock-down effect, is required. Here, we describe the validation of adenoviral vectors that express hairpin RNAs that are further processed to siRNAs. Infection of cell lines, or primary human cells, with these viruses leads to an efficient, sequence-specific, and prolonged reduction of the corresponding target mRNA, resulting in a reduction of the encoded protein level in the cell. For knock-down of one of the targets, GalphaS, we have measured inhibition of ligand-dependent, G-protein-coupled signaling. It is expected that this technology will prove to be of great value in target validation and target discovery efforts. 相似文献
94.
Lu W Parikh PJ El Naqa IM Nystrom MM Hubenschmidt JP Wahab SH Mutic S Singh AK Christensen GE Bradley JD Low DA 《Medical physics》2005,32(4):890-901
We have developed a four-dimensional computed tomography (4D CT) technique for mapping breathing motion in radiotherapy treatment planning. A multislice CT scanner (1.5 mm slices) operated in ciné mode was used to acquire 12 contiguous slices in each couch position for 15 consecutive scans (0.5 s rotation, 0.25 s between scans) while the patient underwent simultaneous quantitative spirometry measurements to provide a sorting metric. The spirometry-sorted scans were used to reconstruct a 4D data set. A critical factor for 4D CT is quantifying the reconstructed data set quality which we measure by correlating the metric used relative to internal-object motion. For this study, the internal air content within the lung was used as a surrogate for internal motion measurements. Thresholding and image morphological operations were applied to delineate the air-containing tissues (lungs, trachea) from each CT slice. The Hounsfield values were converted to the internal air content (V). The relationship between the air content and spirometer-measured tidal volume (v) was found to be quite linear throughout the lungs and was used to estimate the overall accuracy and precision of tidal volume-sorted 4D CT. Inspection of the CT-scan air content as a function of tidal volume showed excellent correlations (typically r>0.99) throughout the lung volume. Because of the discovered linear relationship, the ratio of internal air content to tidal volume was indicative of the fraction of air change in each couch position. Theoretically, due to air density differences within the lung and in room, the sum of these ratios would equal 1.11. For 12 patients, the mean value was 1.08 +/- 0.06, indicating the high quality of spirometry-based image sorting. The residual of a first-order fit between v and V was used to estimate the process precision. For all patients, the precision was better than 8%, with a mean value of 5.1% +/- 1.9%. This quantitative analysis highlights the value of using spirometry as the metric in sorting CT scans. The 4D reconstruction provides the CT data required to measure the three-dimensional trajectory of tumor and lung tissue during free breathing. 相似文献
95.
Uptake of host cell transforming growth factor-beta by Trypanosoma cruzi amastigotes in cardiomyocytes: potential role in parasite cycle completion 下载免费PDF全文
96.
Michelle K Williamson Jane Pirkis Jon J Pfaff Orla Tyson Moira Sim Ngaire Kerse Nicola T Lautenschlager Nigel P Stocks Osvaldo P Almeida 《BMC medical research methodology》2007,7(1):42
Background
Recruiting and retaining GPs for research can prove difficult, and may result in sub-optimal patient participation where GPs are required to recruit patients. Low participation rates may affect the validity of research. 相似文献97.
Pooling of clinical specimens prior to testing for Chlamydia trachomatis by PCR is accurate and cost saving 下载免费PDF全文
Currie MJ McNiven M Yee T Schiemer U Bowden FJ 《Journal of clinical microbiology》2004,42(10):4866-4867
The accuracy and cost savings of pooling specimens prior to testing for Chlamydia trachomatis by PCR were evaluated with genital and urine specimens (n = 2,600). There was a 60% reduction in tests without significant loss of accuracy. The efficiency of pooling vaginal swabs is demonstrated for the first time. 相似文献
98.
Cohen JH Faughnan ME Letarte M Vandezande K Kennedy SJ Krahn MD 《American journal of medical genetics. Part A》2005,137(2):153-160
Endoglin (ENG) and ALK-1 mutations cause hereditary hemorrhagic telangiecstasia (HHT), an autosomal dominant disorder leading to vascular dysplasia in the form of mucocutaneous telangiectasia and visceral arteriovenous malformations (AVMs). We proposed to compare two alternative strategies for management of HHT: screening HHT families with molecular diagnostic tests followed by targeted clinical screening versus conventional clinical screening. A decision analytic model was constructed to compare screening strategies for a hypothetical HHT family. The family consists of 1 index case and 13 relatives. The clinical screening protocol in use at the Canadian HHT Center in Toronto was assumed to be the standard of care. Unit costs for clinical screening (in Canadian dollars) were obtained from the 2003 Ontario Health Insurance Schedule of Benefits. Genetic screening costs were estimated for quantitative multiplex PCR and sequencing of Endoglin (ENG) and ALK-1 genes, as performed at HHT Solutions, Toronto. The genetic screening strategy resulted in a net cost of $4,060 per individual versus $5,975 for the clinical screening strategy. The genetic screening strategy would save $1,915 per family member or $26,810 saved per family. Sensitivity analyses revealed that the genetic screening strategy was cost saving over all plausible ranges of input variables for all hypothetical families tested. We concluded that a genetic screening strategy with targeted clinical screening is more economically attractive than conventional clinical screening and results in a reduction in the number of clinical tests for family members who do not have HHT. 相似文献
99.
Regulation of CD23 in the chronic inflammatory response in asthma: a role for interferon-gamma and heat shock protein 70 in the TH2 environment. 总被引:2,自引:0,他引:2
Michelle S Harkins Pope L Moseley Gary K Iwamoto 《Annals of allergy, asthma & immunology》2003,91(6):567-574
BACKGROUND: Monocytic cells and alveolar macrophages (AMs) are activated in patients with asthma, producing inflammatory cytokines. This occurs despite a TH2 environment that consists of the cytokines interleukin (IL) 4, IL-10, and IL-13. The mechanism by which this occurs may involve cross-linking of the low-alphaffinity IgE receptor CD23. OBJECTIVE: To determine the effect of the TH2 environment with interferon-gamma (IFN-gamma) and heat shock protein 70 (HSP 70) on CD23 receptor expression and tumor necrosis factor alpha (TNF-alpha) production. METHODS: We examined the effect of IL-4 and IL-13 in culture with IFN-gamma and HSP 70 on CD23 expression in both THP-1 cells and AMs from healthy controls via flow cytometry. AMs from mild asthmatic patients and THP-1 cells were evaluated for TNF-alpha production after cross-linking CD23 with immune complexes. RESULTS: Asthmatic AMs stimulated with anti-IgE exhibited a 5.7- +/- 1.9-fold increase in TNF-alpha protein. AMs from healthy controls increased the geometric mean +/- SD of CD23 2.00- +/- 0.50-fold in IL-4 and 2.14- +/- 0.50-fold in IL-13. THP-1 cells cultured with IL-4 and IL-13 then stimulated with IFN-gamma or HSP 70 increased CD23 expression above baseline as follows: IL-4, 2.16- +/- 0.31-fold; IL-13, 2.66- +/- 0.43-fold; IFN-gamma, 2.03- +/- 0.34-fold; IL-4/IFN-gamma, 9.14- to 4.02-fold; IL-13/IFN-gamma, 11.51- +/- 5.51-fold; IL-4/HSP, 5.20- +/- 0.61-fold; and IL-13/HSP, 5.60- +/- 0.79-fold. Stimulating the CD23 receptor with immune complexes significantly increased TNF-alpha production by THP-1 cells stimulated with IFN-gamma, IL-4, IL-13, or a combination of these. CONCLUSIONS: Both IFN-gamma and HSP 70, in the TH2 environment, up-regulate CD23 expression and thus may play an important role in maintaining the chronic inflammatory state in asthma. 相似文献
100.
Le Caignec C De Mas P Vincent MC Bocéno M Bourrouillou G Rival JM David A 《American journal of medical genetics. Part A》2005,(2):175-180
Thirty patients have been described with cytogenetically visible deletion of the short arm of chromosome 6. However, subtelomeric 6p deletion detected by subtelomeric specific probes has been reported only twice. We report two new patients with terminal 6p deletion detected by subtelomeric screening using fluorescence in situ hybridization (FISH). The two patients exhibited mental retardation, ocular abnormalities, hearing loss, and a characteristic facial appearance. Detailed FISH analyses with probes covering the distal 6p25 region estimated the size of the terminal deletions to approximately 5.5 Mb and approximately 4.8 Mb. Array-based comparative genomic hybridization (array CGH) was used to confirm the cryptic deletions. Most patients with subtelomeric defects lack a characteristic phenotype. However, some of the subtelomeric deletions result in a specific phenotype, which can direct the clinician towards the diagnosis. Submicroscopic 6p deletion appears to be a recognizable clinical phenotype, and this region should be thoroughly investigated with FISH probes, including at least a subtelomeric 6p probe and a probe covering FOXC1, for patients presenting with a characteristic facial appearance, ocular abnormalities, predominantly anterior-chamber eye defects, hearing loss, and mental retardation. 相似文献