A current concept of the serological response to human immunodeficiency virus (HIV) infection in humans is that antibodies to core antigens (p55, p24, and p15) are detectable earlier during initial stages of antibody production than antibodies against envelope antigens (gp160, gp120, and gp41). Comparative studies of Western blot (immunoblot), radioimmunoprecipitation assay (RIPA), and enzyme-linked immunosorbent assay (ELISA) during initial antibody production are limited to case reports and have not resolved the issue. Thirty of the 37 participants who are part of a prospective study had at least one specimen that was negative for anti-gp41 but had one or more other bands on Western blot. Twenty-seven of these 30 specimens were reactive for anti-gp120/160 in the RIPA. Of the same 30 specimens, kits from Bionetics identified 2 (7%), ElectroNucleonics 4 (13%), Abbott 13 (43%), Du Pont 25 (83%), and Genetic Systems 25 (83%). All participants had evidence of serological progression by Western blot, including a gp41 band, on subsequent visits; the ELISA kits of all manufacturers identified these later specimens with greater accuracy. These data show that the RIPA detects anti-envelope antibodies that may be not detectable by Western blot and that the production of anti-envelope antibodies approximately parallels the production of anti-core antibodies. The false-negative results by ELISA would permit transmission of HIV by blood transfusion from donors in early stages of infection. The sensitivity of licensed ELISA kits should be improved to identify antibody as soon as possible after infection. 相似文献
HIV-1 plasma RNA is a prognostic indicator of HIV-1, and increased levels of HIV-1 plasma RNA are associated with rapid progression to AIDS. Because chemokines and chemokine receptors are involved in the binding and entry of HIV-1, possible effects of host genetics on viral RNA levels should be visible in early infection. HIV-1 plasma RNA was measured within 2 years of seroconversion in 198 seroincident injection drug users followed in the AIDS Link to Intravenous Experience cohort. Genetic variants were identified in the chemokine receptors (CCR2, CCR5, and CCR5 promoter) and the chemokine RANTES using TaqMan and restriction fragment length polymorphism assays. Linear regression of RANTES haplotypes on early HIV-1 plasma RNA identified individuals homozygous for the RANTES R1 haplotype as having a lower viral load by almost one-half log10 unit compared with those bearing non-RANTES R1 haplotypes (-0.43, 95% confidence interval: -0.74, -0.12). Genetic variants in RANTES may downregulate RANTES gene expression and increase early HIV-1 plasma RNA. Because RANTES is a critical chemokine and competitively inhibits HIV-1 by binding to its receptor CCR5, treatment to enhance RANTES expression may assist in delaying the progression of AIDS by decreasing the initial viral load. 相似文献
Brachytherapy can be employed in the primary or salvage treatment of head and neck cancer. The advantage of brachytherapy is the stereotactic limitation of radiation exposure to noninvolved tissues. Wound complications associated with brachytherapy have been discussed only sporadically in the literature. This retrospective study examines 28 patients, 20 for initial treatment and eight for salvage, with varying site and stage head and neck cancer treated with brachytherapy in addition to external beam radiation therapy and/or surgery. The overall complication rate was 50% (14/28), with infection and minor flap breakdown being the most common problems. Tumor site in the primary treatment group was the only significant factor in wound complications. In the salvage group complications were minor and primarily related to flap coverage of brachytherapy catheters. 相似文献
PURPOSE: In this study, the authors studied the use of a dual-detector gamma camera to measure the glomerular filtration rate (GFR). METHODS: Thirty-three patients with a wide range of renal function participated in this study. The GFR was measured using a dual-detector gamma camera by calculating the geometric mean of activity from each kidney and using an outline background. These results were compared with the GFR estimates obtained from Tc-99m DTPA plasma clearance using a multiple blood sample method. RESULTS: Correlation was excellent between GFR estimated using the dual-detector gamma camera and GFR measured using the plasma clearance of Tc-99m DTPA with multiple blood samples (r = 0.89). The correlation was especially strong in children younger than 13 years (r = 0.94). CONCLUSION: Measuring the GFR using a dual-detector gamma camera and calculating the geometric mean of renal activity yields relatively accurate results. 相似文献
Ulcerative colitis (UC) is a chronic recurrent inflammation of the colon. It has been proposed that the UC pathogenesis may be related to vitamin D deficiency and/or vitamin D administration in UC patients may have an ameliorating effect on the intestinal inflammation. The aim of this study was to assess the effect of vitamin D on the serum levels of immune cytokines in UC patients. In this double‐blind randomized controlled trial, 90 mild‐to‐moderate UC patients were assigned to get either a single muscular injection of 7.5 mg vitamin D3 or 1 mL normal saline as placebo. Three months later serum levels of IL‐4, IL‐10, IL‐12p70, IFN‐γ, and TNF‐α were measured. Two group variables were compared using independent t‐test and analysis of covariance (ANCOVA). There was a significant increase in vitamin D only in the vitamin D group. Compared to placebo, vitamin D had significant decreasing effects on serum TNF‐α, IFN‐γ, and IL12p70 levels, but it had no significant effect on serum levels of IL4 and IL10. Vitamin D seems to inhibit Th1 immune responses and have no effect on Th2 responses. The findings of this study support several in vitro studies, which suggest a therapeutic immunomodulatory potential of vitamin D. 相似文献
This retrospective cohort study examined electronic medical records of HIV-positive patients in California (N = 7,834) to find the prevalence of any psychiatric condition and the associations between several factors and the likelihood of these disorders. Approximately 53 % of the patients in this study had a documented psychiatric condition, including 23 % who had a mood disorder, 19 % who had a substance-related disorder, and 16 % who had an anxiety disorder. After controlling for potential confounders, significant positive associations (p < 0.001) were found between female gender and the presence of any mood disorder (adjusted odds ratio [95 % confidence interval, 95 %CI] = 1.58 [1.26–1.99]) or anxiety disorder (AOR = 1.54 [1.18–2.02]) and between homosexual orientation and the presence of any psychiatric condition (AOR = 1.33 [1.15–1.55]), mood disorder (AOR = 1.71 [1.42–2.07]), or anxiety disorder (AOR = 1.41 [1.22–1.88]). There were also significant negative associations between African-American race and the presence of any psychiatric condition (AOR = 0.68 [0.60–0.77]), mood disorder (AOR = 0.74 [0.64–0.86]), anxiety disorder (AOR = 0.43 [0.36–0.52]), or substance-related disorder (AOR = 0.78 [0.67–0.91]) and between state/federal insurance and the presence of any psychiatric condition (AOR = 0.70 [0.62–0.79]), mood disorder (AOR = 0.71 [0.62–0.80]), or anxiety disorder (AOR = 0.77 [0.66–0.89]). 相似文献
Purpose: To review various types of electroencephalographic activities of the brain and present an overview of brain–computer interface (BCI) systems’ history and their applications in rehabilitation. Methods: A scoping review of published English literature on BCI application in the field of rehabilitation was undertaken. IEEE Xplore, ScienceDirect, Google Scholar and Scopus databases were searched since inception up to August 2012. All experimental studies published in English and discussed complete cycle of the BCI process was included in the review. Results and discussion: In total, 90 articles met the inclusion criteria and were reviewed. Various approaches that improve the accuracy and performance of BCI systems were discussed. Based on BCI’s clinical application, reviewed articles were categorized into three groups: motion rehabilitation, speech rehabilitation and virtual reality control (VRC). Almost half of the reviewed papers (48%) concentrated on VRC. Speech rehabilitation and motion rehabilitation made up 33% and 19% of the reviewed papers, respectively. Among different types of electroencephalography signals, P300, steady state visual evoked potentials and motor imagery signals were the most common. Conclusions: This review discussed various applications of BCI in rehabilitation and showed how BCI can be used to improve the quality of life for people with neurological disabilities. It will develop and promote new models of communication and finally, will create an accurate, reliable, online communication between human brain and computer and reduces the negative effects of external stimuli on BCI performance.
Implications for Rehabilitation
The field of brain–computer interfaces (BCI) is rapidly advancing and it is expected to fulfill a critical role in rehabilitation of neurological disorders and in movement restoration in the forthcoming years.
In the near future, BCI has notable potential to become a major tool used by people with disabilities to control locomotion and communicate with surrounding environment and, consequently, improve the quality of life for many affected persons.
Electrical field recording at the scalp (i.e. electroencephalography) is the most likely method to be of practical value for clinical use as it is simple and non-invasive. However, some aspects need future improvements, such as the ability to separate close imagery signal (motion of extremities and phalanges that are close together).
Evolution of HIV-1 env sequences was studied in 15 seroconverting injection drug users selected for differences in the extent of CD4 T cell decline. The rates of increase of either sequence diversity at a given visit or divergence from the first seropositive visit were both higher in progressors than in nonprogressors. Viral evolution in individuals with rapid or moderate disease progression showed selection favoring nonsynonymous mutations, while nonprogressors with low viral loads selected against the nonsynonymous mutations that might have resulted in viruses with higher levels of replication. For 10 of the 15 subjects no single variant predominated over time. Evolution away from a dominant variant was followed frequently at a later time point by return to dominance of strains closely related to that variant. The observed evolutionary pattern is consistent with either selection against only the predominant virus or independent evolution occurring in different environments within the host. Differences in the level to which CD4 T cells fall in a given time period reflect not only quantitative differences in accumulation of mutations, but differences in the types of mutations that provide the best adaptation to the host environment. 相似文献
Objective: To determine the efficacy of tranexamic acid (TXA) in the management of acute upper gastrointestinal (GI) bleeding.Methods: A total of 70 patients with acute upper GI bleeding were included in this double-blinded randomized controlled clinical trial from September 2018 to December 2018. Patients were divided into the control group (received fluid therapy and intravenous infusion of pantoprazole, 35 cases) and the TXA group (received intravenous TXA besides the treatment of control group, 35 cases). Rebleeding, admission duration, and need for blood transfusion were compared between the two groups. Results: Fifteen patients (42.9%) in the TXA group and 10 patients (28.6%) in the control group stayed in hospital for more than 3 days during their admission (P=0.21). Rebleeding occurred in 8 patients (22.9%) and 5 patients (14.3%) of the TXA group and the control group, respectively (P=0.35). More patients in the TXA group (21 cases, 60%) received blood transfusion than the control group (8 cases, 22.9%) (P=0.02). Conclusions: TXA did not improve the outcome of patients with acute upper GI bleeding. 相似文献
Patients and physicians often cite symptom control as one of their most important goals in cancer care. Despite this, a previous systematic review found few tools for evaluating the quality of supportive cancer management. We developed a comprehensive set of quality indicators for evaluating pain and nonpain symptom management as well as care planning needs in cancer patients. Based on the prevalence and quality-of-life data, clinician-researchers prioritized pain, psychosocial distress, dyspnea, nausea and vomiting, fatigue and anorexia, treatment-associated toxicities, and information and care planning for quality-indicator development. Using search terms and selection criteria, we identified English-language documents from Medline (1997–2007) and Internet-based searches. Based on this evidence, clinician-reviewers proposed process quality indicators. We then used the VA Health Services Research and Development (VA HSR & D) appropriateness methods to compile the ratings of a multidisciplinary, international expert panel of the validity and feasibility of each indicator. The panel judged 92 out of 133 (69%) proposed quality indicators valid and feasible (15 out of 23 pain, 5 out of 6 depression, 8 out of 11 dyspnea, 15 out of 19 nausea and vomiting, 13 out of 26 fatigue and anorexia, 23 out of 32 other treatment-associated toxicities, and 13 out of 16 information and care planning). Of the final indicators, 67 are potentially useful for inpatient and 81 for outpatient evaluation, and 26 address screening, 12 diagnostic evaluation, 20 management, and 21 follow-up. These quality indicators provide evidence-explicit tools for measuring processes critical to ensuring high-quality supportive cancer care. Research is needed to characterize adherence to recommended practices and to evaluate the use of these measures in quality improvement efforts. 相似文献