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71.
Dezzutti CS Guenthner PC Daniel S Utz U Cabrera T Marshall JH Bianco C Lal RB Cowan EP 《Clinical and diagnostic laboratory immunology》2003,10(4):715-717
A potential public health concern is the reported detection of the human T-lymphotropic virus (HTLV) tax gene in the lymphocytes of up to 11% of a low-risk group of New York City blood donors (NYBD). This study aimed to independently confirm the prevalence of HTLV tax sequences in 293 NYBD. All NYBD tested negative for antibodies to HTLV types 1 and 2 and HTLV Tax. HTLV tax sequences were not detected in the NYBD lymphocytes. These data demonstrate the lack of HTLV-1 tax in this group of NYBD at low risk for HTLV infection. 相似文献
72.
Tissue microarrays (TMAs) have been commonly used to study protein expression by immunohistochemistry (IHC). However, limited data exist on the validity of using TMAs to study gene amplification. In this study, we evaluated the feasibility of using breast carcinoma TMAs to study HER-2 gene amplification by fluorescence in situ hybridization (FISH). In addition, hormonal receptor status (ER and PR) and HER-2 protein overexpression by IHC were also studied, and results were compared with whole tissue sections. FISH for HER-2 was performed on formalin-fixed paraffin-embedded tissue from 114 invasive breast carcinomas both on whole tissue sections and on TMAs containing the same tumors. The TMA was created using 0.6-mm tissue cores with four sampled cores per tumor from the same tissue block used for whole section FISH. The PathVysion HER-2 probe kit was used for the FISH analysis. A ratio of HER-2:Chromosome17 > or =2.0 was interpreted as positive for gene amplification. The ER or PR was interpreted as positive when nuclear staining was detected in more than 10% of tumor cells. The HER-2 IHC (HercepTest; DAKO Corp, Carpinteria, CA) results were interpreted as 0, 1+, 2+, and 3+ according to standard criteria. The FISH results in the TMA and whole sections were concordant in 99 out of 101 successfully analyzed cases (99%). The FISH scores were consistent among the two to four cores in the majority of the cases. ER and PR results were concordant between whole sections and TMA cores in 97% (107/110) and 89% (97/109) cases, respectively. The overall concordance for HER-2 status by IHC between whole sections and TMA cores was 86% (94 out of 109 cases). TMAs are a reliable approach to study HER-2 gene amplification in a high throughput manner. 相似文献
73.
Madan Jagasia Jennifer Giglia Wichai Chinratanalab Sheri Dixon Heidi Chen Haydar Frangoul Brian Engelhardt Stacey Goodman John Greer Adetola Kassim David Morgan Katherine Ruffner Friedrich Schuening 《Biology of blood and marrow transplantation》2007,13(10):1207-1215
Chronic graft-versus-host disease (cGVHD), a common complication after stem cell transplant (SCT), has an impact on morbidity and survival. Previous classification of cGVHD has not been reproducible or prognostic for nonrelapse mortality (NRM). Recently the National Institutes of Health (NIH) consensus criteria were proposed, but the ability of this classification to predict outcome of various subtypes of cGVHD is unknown. Patients (N = 110) undergoing an SCT for a hematologic malignancy and surviving until day 100 posttransplant from 2001 to 2003 were studied. The overall survival (OS) using a landmark analysis at day 100 was 44% versus 66% (no GVHD vs. GVHD, P = .026). The OS of patients with various types of GVHD as proposed by the NIH criteria were significantly different (P < .0001). In a univariate analyses, this was more apparent when patients with any acute features of GVHD were compared to classic cGVHD (3-year OS 46% vs. 68%, P = .033). The 3-year NRM for the entire cohort was 21%, and was not affected by presence or absence of GVHD or subtypes of GVHD. In a multivariable analysis, extensive cGVHD (hazard ratio [HR] 0.35, P = .015) and having any acute feature of GVHD after day 100 (HR 3.36, P = .0144) were significant independent predictors of survival. The OS with different NIH subtypes of GVHD after day 100 from SCT varies, and is superior for patients with classic cGVHD. 相似文献
74.
We compared chromogenic in situ hybridization (CISH) with fluorescence in situ hybridization (FISH) for assessing HER-2/neu gene amplification using tissue microarrays (TMAs) made from formalin-fixed, paraffin-embedded tissue blocks from 113 cases of invasive breast carcinoma. TMAs were created using 0.6-mm tissue cores with 4 sampled cores per tumor. For both assays, a HER-2/chromosome 17 signal ratio of 2.0 or more was considered positive for gene amplification. The average ratio of cores from the same tumor was used for determination of gene amplification status of that particular tumor Of 113 cases, 102 were tested successfully by both assays. The results were concordant in 100.0% of cases (63 amplified; 39 nonamplified). All 22 cases of borderline (ratio, 2.0-2.5) or low-level (ratio, 2.6-3.9) amplification by FISH also showed HER-2 gene amplification by CISH. CISH is as sensitive as FISH in detecting borderline and low-level HER-2 amplification. Reliable recognition of the invasive carcinoma area by light microscopy and preservation of the test slides are added advantages of CISH. CISH performs as well as FISH in the analysis of HER-2 gene amplification in breast cancer and might have advantages in certain situations. 相似文献
75.
Chaisavaneeyakorn S Moore JM Mirel L Othoro C Otieno J Chaiyaroj SC Shi YP Nahlen BL Lal AA Udhayakumar V 《Clinical and diagnostic laboratory immunology》2003,10(4):631-636
Macrophage inflammatory protein-1 alpha (MIP-1 alpha) and MIP-1 beta play an important role in modulating immune responses. To understand their importance in immunity to placental malaria (PM) and in human immunodeficiency virus (HIV)-PM coinfection, we investigated levels of these chemokines in the placental intervillous blood plasma (IVB plasma) and cord blood plasma of HIV-negative PM-negative, HIV-negative PM-positive, HIV-positive PM-negative, and HIV-positive PM-positive women. Compared to HIV-negative PM-negative women, the MIP-1 beta concentration in IVB plasma was significantly elevated in HIV-negative PM-positive women and HIV-positive PM-positive women, but it was unaltered in HIV-positive PM-negative women. Also, PM-infected women, irrespective of their HIV status, had significantly higher levels of MIP-1 beta than HIV-positive PM-negative women. The MIP-1 alpha level was not altered in association with either infection. The IVB plasma levels of MIP-1 alpha and MIP-1 beta positively correlated with the cord blood plasma levels of these chemokines. As with IVB plasma, only cord plasma from PM-infected mothers had significantly elevated levels of MIP-1 beta compared to PM-negative mothers, irrespective of their HIV infection status. MIP-1 beta and MIP-1 alpha levels in PM-positive women were positively associated with parasite density and malaria pigment levels. Regardless of HIV serostatus, the IVB MIP-1 beta level was significantly lower in women with PM-associated anemia. In summary, an elevated level of MIP-1 beta was associated with PM. HIV infection did not significantly alter these two chemokine levels in IVB plasma. 相似文献
76.
77.
Mayukh Guha Hitesh Lal Tankeswar Boruah Sapan Kumar Atul Sareen Mohit Kumar Patralekh Ramesh Kumar Geetika Khanna 《Indian Journal of Orthopaedics》2021,55(4):1028
Background/Purpose of the StudyC-arm-guided biopsy is a safe and effective technique for evaluating TB spine and is useful in planning therapy. The purpose of this study was to find a correlation between clinically and radiologically suspected TB spine and C-arm image-guided biopsy-proven cases and to study the complications encountered.MethodsAfter evaluating the clinical, laboratory, X-ray and MRI findings, 92 patients with provisionally diagnosed tubercular spine were subjected to C-arm image-guided biopsy.ResultsAmong our 92 cases, histopathology was positive in 55 cases (59.78%). Out of these 55 histologically positive cases, CBNAAT was positive in 42 cases and negative in the rest 13 cases. Overall, among the 92 cases, CBNAAT was positive in 51(55.43%) of cases, and out of these, histopathology turned out to be positive in 42 of cases. Out of 41 cases with negative CBNAAT, histopathology was suggestive of tuberculosis in 13. The strength of agreement between CBNAAT and histopathology was statistically significant (p < 0.0001; kappa = 0.511). No complication such as bleeding, nerve/cord injury, infection, injury to aorta or pneumothorax was encountered during and after the C-arm biopsy in any case.ConclusionC-arm image-guided biopsy is reasonably accurate and should be used as a tool for diagnosis of TB spine. We recommend histopathological examination as a key component for the diagnosis of TB spine, as it is precise and consumes relatively shorter time. CBNAAT is more rapid but is not a substitute for histopathology for spine TB diagnosis. 相似文献
78.
Trevor A. Hart David M. Moore Syed W. Noor Nathan Lachowsky Daniel Grace Joseph Cox Shayna Skakoon-Sparling Jody Jollimore Abbie Parlette Allan Lal Herak Apelian Jordan M. Sang Darrell H. S. Tan Gilles Lambert the Engage Study Team 《Canadian journal of public health. Revue canadienne de santé publique》2021,112(6):1020
ObjectivesThe last Canadian biobehavioural surveillance study of HIV and other sexually transmitted and blood-borne infections (STBBI) among gay, bisexual and other men who have sex with men (GBM) was conducted in 2010. We designed a study to measure STBBI prevalence among GBM in metropolitan Montreal, Toronto and Vancouver and to document related preventive and risk behaviours.MethodsThe Engage Cohort Study used respondent-driven sampling (RDS) to recruit GBM who reported sex with another man in the past 6 months. At baseline, we examined recruitment characteristics of the samples, and the RDS-II-adjusted distributions of socio-demographics, laboratory-confirmed HIV and other STBBI prevalence, and related behaviours, with a focus on univariate differences among cities.ResultsA total of 2449 GBM were recruited from February 2017 to August 2019. HIV prevalence was lower in Montreal (14.2%) than in Toronto (22.2%) or Vancouver (20.4%). History of syphilis infection was similar across cities (14–16%). Vancouver had more HIV-negative/unknown participants who reported never being HIV tested (18.6%) than Toronto (12.9%) or Montreal (11.5%). Both Montreal (74.9%) and Vancouver (78.8%) had higher proportions of men who tested for another STBBI in the past 6 months than Toronto (67.4%). Vancouver had a higher proportion of men who used pre-exposure prophylaxis (PrEP) in the past 6 months (18.9%) than Toronto (11.1%) or Montreal (9.6%).ConclusionThe three largest cities of Canada differed in HIV prevalence, STBBI testing and PrEP use among GBM. Our findings also suggest the need for scale-up of both PrEP and STI testing among GBM in Canada. 相似文献
79.
Mounissamy Vassanda Coumar Parihar Raghbendra Singh Dwivedi Anil Kumar Saha Jayanta Kumar Rajendiran Selladurai Lakaria Brij Lal Patra Ashok Kumar 《Bulletin of environmental contamination and toxicology》2021,106(3):536-544
Bulletin of Environmental Contamination and Toxicology - An experiment was conducted to study the effects of co-composted products of municipal solid waste (MSW) and pigeon pea biochar (PPB) on... 相似文献