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101.
102.
Fine-needle aspiration cytology remains a useful tool for preoperative diagnosis of breast lesions. We describe a case of adenoid cystic carcinoma (ACC) of the breast detected by ultrasound-guided fine-needle aspiration (FNA). Subsequent histopathology corroborated the diagnosis. ACC is a rare but distinctive neoplasm of the breast that can be accurately diagnosed by FNA. Its infrequent presentation, favorable prognosis, and relatively conservative management in the breast prompt us to reinforce its features. 相似文献
103.
Blacker D Bertram L Saunders AJ Moscarillo TJ Albert MS Wiener H Perry RT Collins JS Harrell LE Go RC Mahoney A Beaty T Fallin MD Avramopoulos D Chase GA Folstein MF McInnis MG Bassett SS Doheny KJ Pugh EW Tanzi RE;NIMH Genetics Initiative Alzheimer's Disease Study Group 《Human molecular genetics》2003,12(1):23-32
Alzheimer's disease (AD) is a devastating neurodegenerative disorder of late life with complex inheritance. Mutations in three known genes lead to the rare early-onset autosomal dominant form of AD, while a common polymorphism (epsilon 4) in the gene encoding apolipoprotein E (APOE ) is a risk factor for more typical late-onset (>60 years) AD. A recent study concluded that there are up to four additional genes with an equal or greater contribution to the disease. We performed a 9 cM genome screen of 437 families with AD, the full National Institute of Mental Health (NIMH) sample, which has been carefully ascertained, evaluated and followed by our group over the last decade. Performing standard parametric and non-parametric linkage analyses, we observed a 'highly significant' linkage peak by Lander and Kruglyak criteria on chromosome 19q13, which probably represents APOE. Twelve additional locations-on 1q23, 3p26, 4q32, 5p14, 6p21, 6q27, 9q22, 10q24, 11q25, 14q22, 15q26 and 21q22-met criteria for 'suggestive' linkage [i.e. two-point lod score (TLS) >/=1.9 and/or multipoint lod score (MLS) >/=2.2] in at least one of our analyses. Although some of these will surely prove to be false positives, these linkage signals should provide a valuable framework for future studies aimed at identifying additional susceptibility genes for late-onset AD. 相似文献
104.
Bastien N Ward D Van Caeseele P Brandt K Lee SH McNabb G Klisko B Chan E Li Y 《Journal of clinical microbiology》2003,41(10):4642-4646
105.
Susceptibility of diverse primary HIV isolates with varying co-receptor specificity's to CXCR4 antagonistic compounds 总被引:2,自引:0,他引:2
Owen SM Rudolph D Schols D Fujii N Yamamoto N Lal RB 《Journal of medical virology》2002,68(2):147-155
The chemokine receptors CCR5 and CXCR4 are an obvious target for HIV therapies. Two compounds, T-22 and AMD-3100, have been shown to inhibit infection of CXCR4-using HIV-1 isolates. The specificity of T-22 and AMD-3100 was further confirmed by their ability to block entry of HIV-1 in GHOST-CXCR4 transfected cells with no effect on viral entry in the GHOST-CCR5 cells. The ability of T-22 to block replication of diverse HIV-1 isolates (group M, subtypes A, B, D, E, and F as well as group O) and HIV-2 primary isolates with varying coreceptor specificities ranging from exclusive CCR5 usage to multiple coreceptor usage was examined in detail. T-22 was found to be highly effective (>90%) at blocking infection of diverse HIV-1 (subtypes A-F, and group O) and HIV-2 isolates that use multiple coreceptors in human PBMCs homozygous for a 32-bp deletion in CCR5 (CCR5-/-), but less effective in CCR5 +/+ PBMCs. Additionally, sequential primary HIV-1 isolates obtained from a longitudinal cohort who had switched from single coreceptor usage to a broad range of multiple receptors could be blocked effectively by both T-22 and AMD-3100 in CCR5-/- PBMCs. Our data suggest that CXCR4 antagonistic compounds are highly effective in blocking the entry of X4-tropic HIV-1, and that these compounds could be a useful additive to current anti-retroviral therapy for clinical management of HIV disease. 相似文献
106.
R. O. Jacoby P. N. Bhatt Diane J. Gaertner Abigail L. Smith Elizabeth A. Johnson 《Archives of virology》1987,95(3-4):251-270
Summary The pathogenesis of rat virus (RV) infection was studied in random-bred Sprague-Dawley rats after oronasal inoculation of a recent RV isolate designated RV-Yale (RV-Y). RV-Y was pathogenic for rats inoculated as infants (2 days) whereas rats inoculated as juveniles (4 weeks) had asymptomatic infection and no lesions. Rats inoculated as infants developed pantropic infection accompanied by hepatic necrosis, granuloprival cerebellar hypoplasia and hemorrhagic encephalopathy. Virological and serological studies showed that virus could persist in inoculated rats for at least 35 days and for at least 28 days after seroconversion was first detected. Immuno-histochemical results indicated that RV-Y infects tissues conducive to virus excretion including kidney and lung. RV-Y also was found in genital tissues of some rats. Athymic juvenile rats inoculated intraperitoneally with RV-Y had a poor humoral immune response and harbored infectious virus for at least 3 weeks, whereas infection in euthymic control rats was detected for 1 week. These studies indicate that RV-Y can persists in the presence of humoral immunity and suggest that transmission of infection could occur for a substantial period after seroconversion. They also suggest that immunodeficient rats have increased susceptibility to persistent infection. 相似文献
107.
Polymorphic membrane protein H has evolved in parallel with the three disease-causing groups of Chlamydia trachomatis
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Chlamydia trachomatis is a human pathogen causing trachoma, urogenital disease, and lymphogranuloma venereum (LGV). A family of nine polymorphic membrane protein genes (pmpA to pmpI), resembling autotransporter proteins, has recently been discovered in C. trachomatis. pmp genes are large and predicted to be outer membrane proteins. We hypothesized that they would contain useful nucleotide sequence variability for epidemiologic studies. Since sequence information is available only for serovars D and L2, we sought to determine the amount of diversity within an individual pmp gene among serovars. We used restriction fragment length polymorphism (RFLP) analysis as a primary screen to assess the amount of sequence divergence among the pmp genes for serovars A to L3 of C. trachomatis. RFLP analysis showed little variation for some of the genes, such as pmpA, but substantial variation in others, such as pmpI. pmpH and pmpE yielded RFLP patterns that clustered the 15 serovars into ocular, urogenital, and LGV groups, and both proteins have been localized to the outer membrane. Therefore, we chose to sequence pmpE, pmpH, and pmpI from each of the 15 serovars. Evolutionary analysis showed three distinct divergence patterns. PmpI was least variable, resulting in an ambiguous evolutionary pattern. PmpE showed a high degree of diversity in the ocular strains compared to the other strains. Finally, the evolution of PmpH shows three groups that reflect disease groups, suggesting this protein may play a role in pathogenesis. 相似文献
108.
Coulter P Lema C Flayhart D Linhardt AS Aucott JN Auwaerter PG Dumler JS 《Journal of clinical microbiology》2005,43(10):5080-5084
Lyme disease is usually diagnosed and treated based on clinical manifestations. However, laboratory testing is useful for patients with confusing presentations and for validation of disease in clinical studies. Although cultivation of Borrelia burgdorferi is definitive, prior investigations have shown that no single test is optimal for Lyme disease diagnosis. We applied high-volume blood culture, skin biopsy culture, PCR, and serodiagnosis to a cohort of patients with suspected Lyme disease acquired in Maryland and southern Pennsylvania. The study was performed to confirm the relative utility of culture and to identify laboratory testing algorithms that will supplement clinical diagnosis. Overall, 30 of 86 patients (35%) were culture positive, whereas an additional 15 of 84 (18%) were seropositive only (51% total sero- and culture positive), and PCR on skin biopsy identified 4 additional patients who were neither culture nor seropositive. Among 49 laboratory test-positive patients, the highest sensitivity (100%) for diagnosis was obtained when culture, skin PCR, and serologic tests were used, although serologic testing with skin PCR was almost as sensitive (92%). Plasma PCR was infrequently positive and provided no additional diagnostic value. Although culture is definitive and has a relatively high sensitivity, the results required a mean of 3.5 weeks to recovery. The combination of acute-phase serology and skin PCR was 75% sensitive, offering a practical and relatively rapid alternative for confirming clinical impression. The full battery of tests could be useful for patients with confusing clinical signs or for providing strong laboratory support for clinical studies of Lyme disease. 相似文献
109.
McLennan NF Brennan PM McNeill A Davies I Fotheringham A Rennison KA Ritchie D Brannan F Head MW Ironside JW Williams A Bell JE 《The American journal of pathology》2004,165(1):227-235
The function of the normal conformational isoform of prion protein, PrP(C), remains unclear although lines of research have suggested a role in the cellular response to oxidative stress. Here we investigate the expression of PrP(C) in hypoxic brain tissues to examine whether PrP(C) is in part regulated by neuronal stress. Cases of adult cerebral ischemia and perinatal hypoxic-ischemic injury in humans were compared with control tissues. PrP(C) immunoreactivity accumulates within neuronal processes in the penumbra of hypoxic damage in adult brain, and within neuronal soma in cases of perinatal hypoxic-ischemic injury, and in situ hybridization analysis suggests an up-regulation of PrP mRNA during hypoxia. Rodents also showed an accumulation of PrP(C) in neuronal soma within the penumbra of ischemic lesions. Furthermore, the infarct size in PrP-null mice was significantly greater than in the wild type, supporting the proposed role for PrP(C) in the neuroprotective adaptive cellular response to hypoxic injury. 相似文献
110.
McCarty MF Bielenberg D Donawho C Bucana CD Fidler IJ 《Clinical & experimental metastasis》2002,19(7):609-615
Primary tumor growth and metastasis depend on angiogenesis, which is determined by the balance between proangiogenic and antiangiogenic
molecules. Interferon (IFN)-α and -β inhibit angiogenesis through downregulation of interleukin-8, matrix metalloproteinase-9,
and basic fibroblast growth factor. To provide evidence for the causal role of IFN-α/β in the induction of neoplasms, their
angiogenesis, and hence, progressive growth, we carried out experiments using 129S6 IFN-α/β receptor −/− mice back-crossed
to BALB/c nude mice. Subcutaneous angiogenesis was determined following implantation of gelfoam sponges containing 0.4% agarose
and several proangiogenic molecules. Tumorigenicity and production of lung metastasis were determined subsequent to subcutaneous
and intravenous injections, respectively, of highly metastatic A375SM human melanoma cells. Carcinogenesis was induced by
chronic exposure of mice to UVB radiation (5 kJ/m2, 3 times/week). Angiogenesis, tumorigenicity, and production of metastasis, as well as development of autochthonous skin
tumors, were all accelerated in IFN-α/β receptor −/− mice as compared to control mice. Collectively, the data show that inability
to respond to endogenous IFN-α/β (through a mutation in the IFN-α/β receptor) leads to increased susceptibility to carcinogenesis,
enhanced angiogenesis, tumorigenicity, and metastasis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献