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81.
OBJECTIVES: To determine the levels of residual HIV DNA and RNA in blood and gut reservoirs in aviremic patients, assess correlations among compartmental measurements of HIV burden, and evaluate association with clinical parameters. DESIGN: Cross-sectional analysis of baseline data only, on 40 patients enrolled in phase II study evaluating efficacy of autologous gene-modified CD4+ and CD8+ T cells. All patients were on stable antiretroviral regimen with undetectable plasma HIV RNA (< 50 copies/ml). METHODS: Measurements repeatedly performed over 8-12 weeks pre-intervention: blood HIV DNA, analysis of rectal mucosa-associated lymphoid tissue for both HIV RNA and HIV DNA, and quantitative co-culture of HIV from CD8-depleted peripheral blood mononuclear cells (PBMC). RESULTS: Quantifiable levels of HIV detected in compartments despite undetectable levels of plasma HIV RNA: HIV co-culture of PBMC (88%), blood HIV DNA (95%), rectal biopsy HIV DNA (95%), rectal biopsy HIV RNA (65%). A significant correlation existed among various measures of HIV burden (HIV co-culture, blood HIV DNA, rectal biopsy HIV RNA and DNA) but not between assays and clinical parameters [duration of highly active antiretroviral therapy (HAART), type of HAART]. All assays had comparable or less variability than in plasma viral load assays; HIV co-culture had the highest coefficient of variability whereas the blood HIV DNA assay had the lowest and was considered the most reliable assay. CONCLUSIONS: The data support safety, feasibility and high compliance of quantifying reservoirs of residual HIV in treated subjects with undetectable plasma HIV RNA. Lack of correlation between levels of HIV in residual reservoirs and duration of HAART suggests treatment-mediated viral suppression alone does not lead to reproducible decay in HIV reservoirs.  相似文献   
82.
OBJECTIVE: In spite of the wide usage of mobilized peripheral blood hematopoietic stem and progenitor cells (HSC/HPC) for transplantation, the mechanism of granulocyte colony-stimulating factor (G-CSF)-induced HSC/HPC mobilization has yet to be fully determined. Our previous studies suggested that that G-CSF-induced mobilization may involve the extracellular peptidase CD26 (DPPIV/dipeptidylpeptidase IV). We set out to establish whether CD26 was an essential component of normal G-CSF-induced mobilization of HSC/HPC. MATERIALS AND METHODS: Normal wild-type (WT) control C57BL/6 mice and CD26 knockout (CD26(-/-)) mice, also on a C57BL/6 background, were treated with or without G-CSF and peripheral blood cells, bone marrow cells, and spleen cells were assessed for CFU-GM, BFU-E, and CFU-GEMM content. RESULTS: No statistical difference in the number of CFU-GM, BFU-E, or CFU-GEMM in the peripheral blood, bone marrow, or spleen of untreated WT vs untreated CD26(-/-) mice was observed. G-CSF treatment of WT mice resulted in the mobilization of HPC into the peripheral blood. The number of HPC detected in G-CSF-treated CD26(-/-) mouse peripheral blood was significantly less than the corresponding number of HPC detected in G-CSF-treated WT mouse peripheral blood after either a 2- or 4-day G-CSF regimen. CONCLUSIONS: CD26 plays a critical role in G-CSF-induced mobilization of HPC.  相似文献   
83.
Aetiological factors for oral manifestations of HIV   总被引:2,自引:0,他引:2  
OBJECTIVES: Describe the oral diseases in HIV-infected individuals in London, UK and identify social and medical factors related to the presence of specific oral diseases.
DESIGN: Cross-sectional analytic study.
SETTING: Dental clinics.
SUBJECTS: Consecutive sample of 456 patients with HIV infection.
METHODS: Social and medical history and clinical examinations. Univariate and logistic regression analysis.
OUTCOMES: Presence of HIV-associated oral disease.
RESULTS: 80% of patients with AIDS and 50% of patients with HIV had a specific oral disease. The most common diseases were hairy leukoplakia (30%), erythematous candidiasis (24%), pseudomembranous candidiasis (14%), angular chielitis (6%), necrotising periodontal disease (8%) and non-recurrent ulceration (6%).
CONCLUSIONS: The presence of erythematous candidiasis was not related to advanced HIV disease. Pseudomembranous candidiasis, hairy leukoplakia and mucosal ulceration were significantly associated with advanced HIV disease. Smoking was also identified as a strong aetiological factor in oral diseases. Longitudinal studies are required to further explore the prognostic significance of oral diseases in HIV infection.  相似文献   
84.
INTRODUCTION Crohn’s disease (CD) is a chronic inflammatory disease of the gastrointestinal tract which commonly affects young adults. It follows a relapsing and remitting course and there is no known cure. However, approximately 10% to 15% have chronic …  相似文献   
85.
Sixteen (11%) of 146 consecutive patients with severe aplastic anemia prepared for engraftment with cyclophosphamide (200 mg/kg) rejected marrow grafts from their HLA-identical siblings. They were given a second marrow transplant from either the same (n = 13) or a second (n = 3) HLA-identical sibling between 23 and 743 (median 86) days after the first transplant. The preparation for the second transplant included cyclophosphamide, 50 mg/kg, on each of four successive days. Twelve hours after each of the first three doses of cyclophosphamide, antithymocyte globulin, 30 mg/kg/dose, was infused. One of the 16 patients died from infection too early after the second transplant to be evaluated, two had failure of engraftment and died with infection, one rejected the second graft and is surviving almost 5 years later with full autologous marrow recovery, and 12 had successful and sustained second grafts. Of these 12, six are surviving between 11 months and 7 3/4 years. Four of the six have no graft-v-host disease (GVHD), while two have chronic GVHD requiring treatment. Five have Karnofsky scores of 100% and one of 90%. Six of the 12 patients with sustained grafts died between 63 days and 38 months after transplantation, four with infections (related in two patients to chronic GVHD), one with acute GVHD, and one with hemorrhage. The average interval from first to second transplant was 308 days during the past five years, compared to 61 days in earlier patients. Five of seven recent patients are surviving, compared to two of nine earlier patients. In conclusion, successful second transplants after cyclophosphamide and antithymocyte globulin are possible in most patients with aplastic anemia who have rejected their first marrow grafts; however, mortality remains high, with only 40% of the patients becoming long-term survivors.  相似文献   
86.
87.
BACKGROUND: Photochemical methods can effectively inactivate extracellular viruses and bacteria found in blood components. Treatment of plasma with methylene blue (MB), a phenothiazine dye, and visible light inactivates enveloped viruses including HIV-1. The effects of MB- treated plasma on cellular components stored in vitro have not been well characterized. STUDY DESIGN AND METHODS: MB-treated plasma (83 microg MB/250 mL plasma) was added to single-donor platelets, stored AS- 1 red cells (RBCs), irradiated RBCs, and frozen-deglycerolized RBCs. In vitro platelet assays performed after 1 and 5 days of storage in MB- treated plasma included pH, pO2, pCO2, HCO3, platelet number, lactate dehydrogenase, glucose, osmotic recovery, and CD62 expression. RBC components were examined at specific intervals for leakage of potassium, plasma hemoglobin level, and percentage of hemolysis. Direct antiglobulin tests, osmotic fragilities, and RBC antigen stability tests were also performed on RBCs stored in MB-treated plasma. Components stored with autologous plasma or nontreated allogeneic plasma served as controls. RESULTS: Similar storage-induced changes in pH, glucose, and platelet numbers, as well as increases in lactate dehydrogenase, CD62 expression, and lactate were seen in single-donor platelets stored with MB-treated and control plasma. Platelet morphology scores and osmotic recoveries were not altered. Plasma hemoglobin and potassium and percentage of hemolysis increased equally in the various RBC components stored with MB-treated or nontreated plasma. Osmotic fragility and RBC antigen stability were not appreciably altered by MB-treated plasma. CONCLUSION: Plasma treated by MB photoinactivation can be used for in vitro resuspension and storage of platelets or RBCs, because of the lack of influence of MB-treated plasma on a variety of in vitro platelet and RBC assays.  相似文献   
88.
89.
The hyoid bone and larynx elevate to protect the airway during swallowing. However, it is unknown whether hyolaryngeal movements during swallowing can adjust and adapt to predict the presence of a persistent perturbation in a feed-forward manner (adaptive motor learning). We investigated adaptive motor learning in nine healthy adults. Electrical stimulation was administered to the anterior neck to reduce hyolaryngeal elevation, requiring more strength to swallow during the perturbation period of this study. We assessed peak hyoid bone and laryngeal movements using videofluoroscopy across thirty-five 5-ml water swallows. Evidence of adaptive motor learning of hyolaryngeal movements was found when (1) participants showed systematic gradual increases in elevation against the force of electrical stimulation and (2) hyolaryngeal elevation overshot the baseline (preperturbation) range of motion, showing behavioral aftereffects, when the perturbation was unexpectedly removed. Hyolaryngeal kinematics demonstrates adaptive, error-reducing movements in the presence of changing and unexpected demands. This is significant because individuals with dysphagia often aspirate due to disordered hyolaryngeal movements. Thus, if rapid motor learning is accessible during swallowing in healthy adults, patients may be taught to predict the presence of perturbations and reduce errors in swallowing before they occur.  相似文献   
90.
Background: Spherophakia is an uncommon diagnosis. This is the first case report of spherophakia evaluated by ultrasound biomicroscopy.
Methods: Ultrasound biomicroscopy is a new diagnostic technique developed by one of the authors and provides images with microscopic resolution of the anterior segment. A patient with spherophakia was evaluated by ultrasound biomicroscopy (Zeiss-Humphrey, 50MHz) before and after YAG laser iridotomy.
Results: Ultrasound biomicroscopic assessment revealed a shallow anterior chamber, a very steep anterior lens curvature, iridolenticular contact, elongated zonules, and an increased distance between the lens equator and the ciliary processes. Angle closure glaucoma was due to a pupil block mechanism. The pupil block was relieved by YAG laser iridotomy.
Conclusions: Ultrasound biomicroscopy is a useful technique to confirm the diagnosis of spherophakia. The pupil block in spherophakia is relieved by YAG laser iridotomy.  相似文献   
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