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991.
Nimmakayalu M Major H Sheffield V Solomon DH Smith RJ Patil SR Shchelochkov OA 《American journal of medical genetics. Part A》2011,155(2):418-423
Microdeletions of the long arm of chromosome 17 are being reported with increasing frequency. Deletions of 17q22q23.2 may represent a genetically recognizable phenotype although its spectrum of genomic abnormalities, clinical manifestations, and critical regions are not fully delineated. Isolated reports and small case series suggest that deletions of 17q22q23.2 result in haploinsufficiency of dosage sensitive genes NOG, TBX2, and TBX4, which may be responsible for many aspects of the phenotype. Shared clinical features in this group of patients include microcephaly, prenatal onset growth restriction, heart defects, tracheoesophageal fistula, and esophageal atresia (TEF/EA), skeletal anomalies, and moderate to severe global developmental delay. We describe a female patient who presented with severe congenital microcephaly, thyroglossal duct cyst, sensorineural hearing loss, mild tracheomalacia, abnormal auricles, pulmonary hypertension, developmental delay, and postnatal onset growth delay. She had no TEF/EA or heart defects. Using a high density oligonucleotide microarray, we identified a microdeletion at 17q22q23.2, resulting in the heterozygous loss of several genes, including TBX2 and TBX4 but not NOG. The breakpoints did not lie within known segmental duplications. This case helps to further delineate the critical region for TEF/EA, which is likely confined to the chromosomal region proximal to 17q23.1, and suggests that genes in 17q23.1q23.2 may be associated with thyroglossal duct cysts. The role of TBX2 and TBX4 in pulmonary hypertension warrants investigation. 相似文献
992.
Nayak AP Green BJ Janotka E Hettick JM Friend S Vesper SJ Schmechel D Beezhold DH 《Clinical and Vaccine Immunology : CVI》2011,18(9):1568-1576
Aspergillus terreus has been difficult to identify in cases of aspergillosis, and clinical identification has been restricted to the broad identification of aspergillosis lesions in affected organs or the detection of fungal carbohydrates. As a result, there is a clinical need to identify species-specific biomarkers that can be used to detect invasive A. terreus disease. Monoclonal antibodies (MAbs) were developed to a partially purified preparation of cytolytic hyphal exoantigens (HEA) derived from A. terreus culture supernatant (CSN). Twenty-three IgG1 isotype murine MAbs were developed and tested for cross-reactivity against hyphal extracts of 54 fungal species. Sixteen MAbs were shown to be specific for A. terreus. HEA were detected in conidia, hyphae, and in CSN of A. terreus. HEA were expressed in high levels in the hyphae during early stages of A. terreus growth at 37°C, whereas at room temperature the expression of HEA peaked by days 4 to 5. Expression kinetics of HEA in CSN showed a lag, with peak levels at later time points at room temperature and 37°C than in hyphal extracts. Serum spiking experiments demonstrated that human serum components do not inhibit detection of the HEA epitopes by MAb enzyme-linked immunosorbent assay (ELISA). Immunoprecipitation and proteomic analysis demonstrated that MAbs 13E11 and 12C4 immunoprecipitated a putative uncharacterized leucine aminopeptidase (Q0CAZ7), while MAb 19B2 recognized a putative dipeptidyl-peptidase V (DPP5). Studies using confocal laser scanning microscopy showed that the uncharacterized leucine aminopeptidase mostly localized to extracellular matrix structures while dipeptidyl-peptidase V was mostly confined to the cytoplasm. 相似文献
993.
994.
Sex differences in asthma, atopy, and airway hyperresponsiveness in a university population. 总被引:1,自引:0,他引:1
BACKGROUND: A male predominance in atopy, a preadolescent male predominance in asthma, and a female predominance in airway hyperresponsiveness (AHR) have been previously documented, mostly in separate populations. OBJECTIVE: We examined gender differences in a single population of 500 randomly selected university students from a previous publication which addressed sensitivity and specificity of histamine bronchoprovocation (Cockcroft et al. J Allergy Clin Immunol. 1992;89:23-30). METHODS: In these 500 subjects (age 21.8 +/- 1.5 years) we assessed gender differences in asthma, atopy, and AHR. We compared our findings with those in the literature from a PUBMED search using the keywords gender, asthma, atopy, AHR, and bronchial reactivity. RESULTS: A diagnosis of asthma made by another physician was seen in 31, a male-to-female ratio of 2.9:1 (P = 0.004). Our definition of asthma increased the total to 52 and reduced the male-to-female ratio to 1.2:1. Atopy was seen in 190, male-to-female ratio of 1.5:1 (P = 0.001). Borderline to mild AHR had a female predominance with a male-to-female ratio of 1:1.5 (P = 0.02), whereas moderate AHR had a marked predominance with a male-to-female ratio of 7:1 (P = 0.03). CONCLUSIONS: In our population, the associations among gender and asthma, atopy, and AHR were similar to those seen in the literature with the exception of males having more severe AHR. This may be the one factor contributing to the higher prevalence of asthma (including previous doctor-diagnosed asthma in our population) in boys and young men. 相似文献
995.
Infants with Ureaplasma urealyticum in the lower respiratory tract are at risk for chronic lung disease (CLD) or bronchopulmonary dysplasia (BPD) but causality has been difficult to prove. The goal of this study was to identify ureaplasma in human neonatal lung tissue using the in situ hybridization (ISH) procedure described in Part 1 (Exp. Mol. Pathol., in press) of this report. By correlating their presence with the histopathologic findings, it may be possible to provide further evidence of the pathogenicity of ureaplasmas and their association with BPD. Lung autopsy tissue from seven infants with positive cultures and seven infants with negative cultures for ureaplasma were included in the study. All culture-positive infants were positive for ureaplasma on ISH and all had histopathologic evidence of BPD. Two of the seven infants with negative cultures were positive for ureaplasma with ISH. Of interest, these two infants were also found to have BPD at autopsy. The other five infants with negative cultures were also negative for ureaplasma on ISH and had no evidence of BPD. This study correlates the presence of U. urealyticum by ISH with the finding of BPD on histopathologic evaluation and provides evidence that it has a role in the development of CLD. 相似文献
996.
Detection of Serum Antibodies to Ovine Progressive Pneumonia Virus in Sheep by Using a Caprine Arthritis-Encephalitis Virus Competitive-Inhibition Enzyme-Linked Immunosorbent Assay 下载免费PDF全文
Lynn M. Herrmann William P. Cheevers Katherine L. Marshall Travis C. McGuire Melinda M. Hutton Gregory S. Lewis Donald P. Knowles 《Clinical and Vaccine Immunology : CVI》2003,10(5):862-865
A competitive-inhibition enzyme-linked immunosorbent assay (cELISA) for detection of antibodies to the surface envelope (SU) of caprine arthritis-encephalitis virus (CAEV) was recently reported (L. M. Herrmann, W. P. Cheevers, T. C. McGuire, D. Scott Adams, M. M. Hutton, W. G. Gavin, and D. P. Knowles, Clin. Diagn. Lab. Immunol. 10:267-271, 2003). The cELISA utilizes CAEV-63 SU captured on microtiter plates using the monoclonal antibody (MAb) F7-299 and measures competitive displacement of binding of the anti-CAEV MAb GPB 74A by goat serum. The present study evaluated the CAEV cELISA for detection of antibodies to ovine progressive pneumonia virus (OPPV) in sheep. Three hundred thirty-two sera were randomly selected from 21,373 sheep sera collected throughout the United States to determine the sensitivity and specificity of cELISA and agar gel immunodiffusion (AGID) based on immunoprecipitation (IP) of [35S]methionine-labeled OPPV antigens as a standard of comparison. A positive cELISA test was defined as >20.9 percent inhibition (% I) of MAb 74A binding based on two standard deviations above the mean % I of 191 IP-negative sheep sera. At this cutoff, there were 2 of 141 false-negative sera (98.6% sensitivity) and 6 of 191 false-positive sera (96.9% specificity). Sensitivity and specificity values for IP-monitored AGID were comparable to those for cELISA for 314 of 332 sera with unambiguous AGID results. Concordant results by cELISA and IP resolved 16 of the 18 sera that were indeterminate by AGID. Additional studies evaluated cELISA by using 539 sera from a single OPPV-positive flock. Based on IP of 36 of these sera, there was one false-negative by cELISA among 21 IP-positive sera (95.5% sensitivity) and 0 of 15 false-positives (100% specificity). We conclude that the CAEV cELISA can be applied to detection of OPPV antibodies in sheep with high sensitivity and specificity. 相似文献
997.
The analytical performance of the NucliSens HIV-1 QT assay, a highly sensitive test based on nucleic acid sequence-based amplification technology, was evaluated in a multicenter trial. Assay specificity was evaluated with 502 plasma (EDTA) specimens from human immunodeficiency virus type 1 (HIV-1)-seronegative volunteer donors. No HIV-1 RNA was reported in any of the donor specimens. Analytical sensitivity and reproducibility were estimated with panels prepared from a high-titer well-characterized HIV-1 RNA stock (5.84 x 10(8) RNA copies/ml). The assay's dynamic range was linear from 10(6) to 10(1) HIV-1 RNA copies, with a lower detectable limit of 25 copies/ml and a 95% detection rate of 176 copies/ml. Sensitivity of the assay to detect HIV-1 RNA in clinical specimens from patients (n = 101) and in commercially available or prepared panels (n = 24) was compared with NASBA HIV-1 RNA QT (an earlier version of NucliSens HIV-1 QT) and with the Food and Drug Administration-approved standard and ultrasensitive AMPLICOR HIV-1 MONITOR, version 1.0, assays. Detection of HIV-1 RNA was reproducible over a 5-log range (mean standard deviation = 0.15 log). The NucliSens and the standard AMPLICOR assays were equivalent in detection of HIV-1 RNA (concentration, 10(3) to 10(5) copies/ml) in 57 clinical specimens. The NucliSens assay was more sensitive in detecting HIV-1 RNA at lower concentrations (=10(2) copies/ml) (44 of 44) than either the standard AMPLICOR test (12 of 19) or the NASBA assay (10 of 25). A 25% increase in HIV-1 RNA detection frequency with panels was observed with the NucliSens assay (23 of 24) compared with the standard AMPLICOR test (17 of 24). The new assay was highly specific and demonstrated good sensitivity with a broad linear dynamic range. 相似文献
998.
Background
Diabetic foot infections are common, serious, and varied. Diagnostic and treatment strategies are correspondingly diverse. It is unclear how patients are managed in actual practice and how outcomes might be improved. Clarification will require study of large numbers of patients, such as are available in medical databases. We have developed and evaluated a system for identifying and classifying diabetic foot infections that can be used for this purpose. 相似文献999.
1000.
Sarah L. McGlasson Fiona Semple Heather MacPherson Mohini Gray Donald J. Davidson Julia R. Dorin 《European journal of immunology》2017,47(4):658-664
Human β‐defensin 3 (hBD3) is a cationic antimicrobial peptide with potent bactericidal activity in vitro. HBD3 is produced in response to pathogen challenge and can modulate immune responses. The amplified recognition of self‐DNA by human plasmacytoid dendritic cells has been previously reported, but we show here that hBD3 preferentially enhances the response to bacterial DNA in mouse Flt‐3 induced dendritic cells (FLDCs) and in human peripheral blood mononuclear cells. We show the effect is mediated through TLR9 and although hBD3 significantly increases the cellular uptake of both E. coli and self‐DNA in mouse FLDCs, only the response to bacterial DNA is enhanced. Liposome transfection also increases uptake of bacterial DNA and amplifies the TLR9‐dependent response. In contrast to hBD3, lipofection of self‐DNA enhances inflammatory signaling, but the response is predominantly TLR9‐independent. Together, these data show that hBD3 has a role in the innate immune‐mediated response to pathogen DNA, increasing inflammatory signaling and promoting activation of the adaptive immune system via antigen presenting cells including dendritic cells. Therefore, our data identify an additional immunomodulatory role for this copy‐number variable defensin, of relevance to host defence against infection and indicate a potential for the inclusion of HBD3 in pathogen DNA‐based vaccines. 相似文献