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31.
We investigated the effect of the intraosseous allotransplantation of the donor-derived hematopoietic stem cells (HSC) CD90+ on chimerism induction and survival of rat hind limb transplants. Eighteen rat hind limb transplantations were performed between Lewis-Brown-Norway and Lewis rats in three groups. Isograft and allograft rejection controls received no treatment. In the experimental group, 0.8 to 1.2 x 10(6) of separated and purified CD90+ HSC cells were transplanted intramedullary into the bone marrow cavity of the recipient's tibia during opposite hind limb transplantation, without immunosuppressive therapy. Transplants from isograft group survived indefinitely. Allograft controls rejected transplants on day 7 posttransplant. The injection of separated and purified CD90+ cells of the donor origin extended survival of the transplanted limbs up to 15 days in group III. We introduced a novel method of transplantation of the CD90+ cells of the donor origin into the recipient's bone marrow cavity. This technique resulted in extended allograft survival, without immunosuppressive therapy. 相似文献
32.
Human islets exhibit distinct islet architecture particularly in large islets that comprise of a relatively abundant fraction of α-cells intermingled with β-cells, whereas mouse islets show largely similar architecture of a β-cell core with α-cells in the periphery. In humans, islet architecture is islet-size dependent. Changes in endocrine cell mass preferentially occurred in large islets as demonstrated in our recent study on pathological changes of the pancreas in patients with type 2 diabetes. ( 1) The size dependency of human islets in morphological changes prompted us to develop a method to capture the representative islet distribution in the whole pancreas section combined with a semi-automated analysis to quantify changes in islet architecture. The computer-assisted quantification allows detailed examination of endocrine cell composition in individual islets and minimizes sampling bias. The standard immunohistochemistry based method is widely applicable to various specimens, which is particularly useful for large animal studies but is also applied to a large-scale analysis of the whole organ section from mice. In this article, we describe the method of image capture, parameters measured, data analysis and interpretation of the data. 相似文献
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Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee. 相似文献
35.
Wade NA Zielinski MA Butsashvili M McNutt LA Warren BL Glaros R Cheku B Pulver W Pass K Fox K Novello AC Birkhead GS 《Journal of acquired immune deficiency syndromes (1999)》2004,36(5):1075-1082
BACKGROUND: Perinatal HIV transmission has declined significantly in New York State (NYS) since implementation of a 3-part regimen of zidovudine prophylaxis in the antenatal, intrapartum, and newborn periods. This study describes the factors associated with perinatal transmission in NYS from 1997 to 2000, the first 4 years of NYS's comprehensive program in which all HIV-exposed newborns were identified through universal HIV testing of newborns. METHODS: This population-based observational study included all HIV-exposed newborns whose infection status was known and their mothers identified in NYS through the universal Newborn HIV Screening Program (NSP) from February 1997 to December 2000. Antepartum, intrapartum, newborn, and pediatric medical records of HIV-positive mothers/infants were reviewed for history of prenatal care, antiretroviral therapy (ART), and infant infection status. Risks associated with perinatal HIV transmission were examined. RESULTS: Perinatal HIV transmission declined significantly from 11.0% in 1997 to 3.7% in 2000 (P < 0.05). Prenatal ART was associated with a decline in perinatal HIV transmission both for monotherapy (5.8%, relative risk [RR] = 0.3, 95% confidence interval: 0.2%-0.5%) and combination therapy [2.4%, RR = 0.1, 95% confidence interval: 0.1%-0.2%) compared with no prenatal antiretroviral prophylaxis (P < 0.05). CONCLUSIONS: Public health policies to improve access to care for pregnant women and advances in clinical care, including receipt of appropriate preventive therapies, have contributed to declines in perinatal HIV transmission in NYS. 相似文献
36.
Detection of chromosomal imbalances in retinoblastoma by matrix-based comparative genomic hybridization 总被引:7,自引:0,他引:7
Zielinski B Gratias S Toedt G Mendrzyk F Stange DE Radlwimmer B Lohmann DR Lichter P 《Genes, chromosomes & cancer》2005,43(3):294-301
The genetic hallmark of retinoblastoma is mutation or deletion of the RB1 gene, whereas other genetic alterations that are also required are largely unknown. To screen for genomic imbalances on a genomewide level, we studied a series of 17 primary retinoblastomas by matrix-based comparative genomic hybridization (matrix-CGH). The matrix-CGH chip contained 6,000 immobilized genomic DNA fragments covering the human genome, with an average resolution of about 500 kb. The most frequent imbalances detected were gains on chromosome arms 1q (12 of 17), 6p (10 of 17), 2p (5 of 17), and 19q (4 of 17) and loss on 16q (7 of 17). Candidate regions could be narrowed to small intervals by the identified minimally overlapping regions on 1q22, 1q32.1q32.2, 2p24.1, and 6p21.33-p21.31. Furthermore, two as-yet-unknown high-level amplifications were detected, each in a single patient, on chromosome bands 1p34.2 and 1p33. Thus, this study identified new chromosomal regions and therefore potential candidate genes that may play a role in retinoblastoma. 相似文献
37.
LN Barlow-Mosha DS Bagenda PK Mudiope MC Mubiru LM Butler MG Fowler PM Musoke 《African health sciences》2012,12(3):249-258
Background
Access to pediatric antiretroviral formulations is increasing in resource-limited countries, however adult FDCs are still commonly used by antiretroviral therapy (ART) programs.Objective
To describe long-term effectiveness of using adult FDC of d4T+3TC+NVP (Triomune) in children for HIV treatment.Methods
Clinical, immunologic, and virologic outcomes of HIV-infected ART-naïve children aged six months to 12 years, were evaluated up to 96 weeks post-ART initiation.Results
From March 2004 to June 2006, 104 children were followed with a median age of 5.4 years, median CD4 cell percent and HIV-1 RNA were 11.0% (IQR 6.7–13.9) and 348,846copies/mL (IQR 160,941–681,313) respectively at baseline. Using Kaplan-Meir estimates, 75% of children had undetectable viral loads (<400copies/mL) at 96weeks of ART. Children with a baseline CD4 cell percent >15% were 3 times more likely to achieve viral load <400copies/mL than those with baseline CD4 cell percent <5% after adjusting for baseline age {aHR = 3.03 (1.10–8.32), p=0.03}; no difference was found among those with CD4 cell percent >5–14.9% and <5%.Conclusion
Treatment with generic adult FDC for HIV-infected Ugandan children led to sustained clinical, immunologic and virologic response during 96 weeks of ART. Early initiation of ART is key to achieving virological success. 相似文献38.
Hardin M Zielinski J Wan ES Hersh CP Castaldi PJ Schwinder E Hawrylkiewicz I Sliwinski P Cho MH Silverman EK 《American journal of respiratory cell and molecular biology》2012,47(2):203-208
We examined the association between single-nucleotide polymorphisms (SNPs) previously associated with chronic obstructive pulmonary disease (COPD) and/or lung function with COPD and COPD-related phenotypes in a novel cohort of patients with severe to very severe COPD. We examined 315 cases of COPD and 330 Caucasian control smokers from Poland. We included three SNPs previously associated with COPD: rs7671167 (FAM13A), rs13180 (IREB2), and rs8034191 (CHRNA 3/5), and four SNPs associated with lung function in a genome-wide association study of general population samples: rs2070600 (AGER), rs11134242 (ADCY2), rs4316710 (THSD4), and rs17096090 (INTS12). We tested for associations with severe COPD and COPD-related phenotypes, including lung function, smoking behavior, and body mass index. Subjects with COPD were older (average age 62 versus 58 years, P < 0.01), with more pack-years of smoking (45 versus 33 pack-years, P < 0.01). CHRNA3/5 (odds ratio [OR], 1.89; 95% confidence interval [CI], 1.5-2.4; P = 7.4 × 10(-7)), IREB2 (OR, 0.69; 95% CI, 0.5-0.9; P = 3.4 × 10(-3)), and ADCY2 (OR, 1.35; 95% CI, 1.1-1.7; P = 0.01) demonstrated significant associations with COPD. FAM13A (OR, 0.8; 95% CI, 0.7-1.0; P = 0.11) approached statistical significance. FAM13A and ADCY2 also demonstrated a significant association with lung function. Thus, in severe to very severe COPD, we demonstrate a replication of association between two SNPs previously associated with COPD (CHRNA3/5 and IREB2), as well as an association with COPD of one locus initially associated with lung function (ADCY2). 相似文献
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