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BACKGROUND: Nephrolithiasis is a well-known complication of indinavir treatment and may result in urological symptoms ranging from renal colic to renal insufficiency. OBJECTIVE: To obtain further knowledge regarding the incidence and risk factors of urological symptoms associated with indinavir sulfate use. METHODS: This study was performed in the ATHENA (AIDS Therapy Evaluation National AIDS Therapy Evaluation Centre) cohort of patients infected with human immunodeficiency virus (HIV) receiving antiretroviral therapy in the Netherlands. The incidence rate of urological symptoms was assessed in a subcohort of 1219 patients starting HIV protease inhibitor treatment after 1996. Urological symptoms were defined as an initial report of nephrolithiasis, renal colic, flank pain, hematuria, renal insufficiency, or nephropathy. Using multivariate Cox regression analysis, risk factors for urological symptoms during indinavir treatment were subsequently studied among the subset of 644 patients who started indinavir treatment after 1996. RESULTS: The incidence of urological symptoms was 8.3 per 100 treatment-years for indinavir vs 0.8 per 100 treatment-years for other HIV protease inhibitors. Risk factors for urological symptoms during indinavir treatment were low weight (relative risk [RR], 2.1; 95% confidence interval [CI], 1.1-3.9), low lean body mass (RR, 1.7; 95% CI, 1.0-2.9), undetectable HIV-1 RNA when starting indinavir treatment (RR, 3.2; 95% CI, 1.5-6.0), prior treatment change because of intolerance (RR, 2.4; 95% CI, 1.2-5.1), indinavir regimens of 1000 mg or more twice daily (RR, 3.1; 95% CI, 1.3-8.2), and warm environmental temperatures (RR, 3.9; 95% CI, 1.7-8.8). Risk estimates were highest among patients with a low lean body mass. CONCLUSION: Increased alertness for urological symptoms is warranted for patients starting indinavir treatment, particularly among those with a low lean body mass, during indinavir regimens of 1000 mg or more twice daily, and in warm weather environments.  相似文献   
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Melatonin has been shown to have a direct inhibitory action on the proliferation of estrogen-responsive MCF-7 human breast cancer cells in culture. In the present study, we examined by flow cytometry whether this inhibitory effect might be exerted on the G1 phase of the cell cycle, thus causing a transition delay into the S phase. In order to further verify this hypothesis we tested the ability of estradiol to "rescue" MCF-7 cells from melatonin inhibition, and the potential of this indoleamine to block the ability of estradiol to rescue the cells from tamoxifen inhibition. Following five days of incubation, melatonin (10(-9)M) increased the fraction of cells in G1 of the cell cycle while simultaneously causing a 50% reduction in the proportion of cells in S phase. The antiproliferative effect of melatonin (10(-5)M) was prevented by the simultaneous treatment of the cells with estradiol (10(-8)M) in clonogenic soft agar culture, or reversed by the addition of estradiol to cells previously incubated with and inhibited by melatonin (10(-9)M) in monolayer culture. Additionally, melatonin blocked the estrogen-rescue of tamoxifen-inhibited cells in both types of culture systems. These results support the hypothesis that the antiproliferative effect of melatonin, like tamoxifen, is cell cycle specific by causing a G1-S transition delay. These results also indicate an important interaction of melatonin with estrogen-mediated mechanisms of MCF-7 cell proliferation.  相似文献   
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SARS-CoV-2 (CoV2) antibody therapies, including COVID-19 convalescent plasma (CCP), monoclonal antibodies, and hyperimmune globulin, are among the leading treatments for individuals with early COVID-19 infection. The functionality of convalescent plasma varies greatly, but the association of antibody epitope specificities with plasma functionality remains uncharacterized. We assessed antibody functionality and reactivities to peptides across the CoV2 and the 4 endemic human coronavirus (HCoV) genomes in 126 CCP donations. We found strong correlation between plasma functionality and polyclonal antibody targeting of CoV2 spike protein peptides. Antibody reactivity to many HCoV spike peptides also displayed strong correlation with plasma functionality, including pan-coronavirus cross-reactive epitopes located in a conserved region of the fusion peptide. After accounting for antibody cross-reactivity, we identified an association between greater alphacoronavirus NL63 antibody responses and development of highly neutralizing antibodies against CoV2. We also found that plasma preferentially reactive to the CoV2 spike receptor binding domain (RBD), versus the betacoronavirus HKU1 RBD, had higher neutralizing titer. Finally, we developed a 2-peptide serosignature that identifies plasma donations with high anti-spike titer, but that suffer from low neutralizing activity. These results suggest that analysis of coronavirus antibody fine specificities may be useful for selecting desired therapeutics and understanding the complex immune responses elicited by CoV2 infection.  相似文献   
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Despite the increasing speculation that oxidative stress and abnormal energy metabolism may play a role in Autism Spectrum Disorders (ASD), and the observation that patients with mitochondrial defects have symptoms consistent with ASD, there are no comprehensive published studies examining the role of mitochondrial variation in autism. Therefore, we have sought to comprehensively examine the role of mitochondrial DNA (mtDNA) variation with regard to ASD risk, employing a multi‐phase approach. In phase 1 of our experiment, we examined 132 mtDNA single‐nucleotide polymorphisms (SNPs) genotyped as part of our genome‐wide association studies of ASD. In phase 2 we genotyped the major European mitochondrial haplogroup‐defining variants within an expanded set of autism probands and controls. Finally in phase 3, we resequenced the entire mtDNA in a subset of our Caucasian samples (~400 proband‐father pairs). In each phase we tested whether mitochondrial variation showed evidence of association to ASD. Despite a thorough interrogation of mtDNA variation, we found no evidence to suggest a major role for mtDNA variation in ASD susceptibility. Accordingly, while there may be attractive biological hints suggesting the role of mitochondria in ASD our data indicate that mtDNA variation is not a major contributing factor to the development of ASD.  相似文献   
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Cytomegalovirus (CMV) infection is common among infants of HIV-infected mothers in resource-limited settings. We examined the prevalence and timing of infant CMV infection during the first year of life using IgG antibody and avidity among HIV-exposed infants in Malawi and correlated the results with the presence of detectable CMV DNA in the blood. The Breastfeeding, Antiretrovirals and Nutrition (BAN) study randomized 2,369 mothers and their infants to maternal antiretrovirals, infant nevirapine, or neither for 28 weeks of breastfeeding, followed by weaning. Stored plasma specimens were tested for CMV IgG and antibody avidity from a random subset of infants who had been previously tested with blood CMV PCR and had available specimens at birth and at 24 and 48 weeks of age. Ninety-four of 127 infants (74.0%) tested at 24 weeks of age had CMV IgG of low or intermediate avidity, signifying primary CMV infections. An additional 22 infants (17.3%) had IgG of high avidity; 19 of them had CMV DNA detected in their blood, indicating infant infections. Taken together, these results show that the estimated prevalence of CMV infection at 24 weeks was 88.9%. By 48 weeks of age, 81.3% of infants had anti-CMV IgG; most of them (70.9%) had IgG of high avidity. The CMV serology and avidity testing, combined with the PCR results, confirmed a high rate of primary CMV infection by 6 months of life among breastfeeding infants of HIV-infected mothers. The CMV PCR in blood detected most, but not all, infant CMV infections.  相似文献   
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