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In this study, we target arginine auxotrophy of AML cell lines using human arginase I cobalt-PEG5000. HuArgI(Co)-PEG5000 was cytotoxic to all AML cell lines tested. Mononuclear cells and CD34+ blasts were not sensitive demonstrating the selectivity of HuArgI(Co)-PEG5000-induced arginine deprivation. Addition of l-citrulline led to the rescue of five cell lines. The four cell lines that were not rescued by l-citrulline did not express argininosuccinate synthetase-1, indicating complete arginine auxotrophy. Inhibition of autophagy increased cell sensitivity to HuArgI(Co)-PEG5000 demonstrating the protective role of autophagy following arginine deprivation.  相似文献   
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Mobile health (mHealth) interventions to promote antiretroviral therapy (ART) adherence have shown promise; however, among persons living with HIV who abuse methamphetamine (MA), effective tailoring of content to match the expressed needs of this patient population may be necessary. This study aimed (1) to understand patient perspectives of barriers and facilitators of ART adherence among people with HIV who use MA, and (2) to obtain feedback on the thematic content of an mHealth intervention in order to tailor the intervention to this subgroup. Two separate focus groups, each with 10 HIV+/MA+ individuals, were conducted. Transcribed audio recordings were qualitatively analyzed to identify emergent themes. Inter-rater reliability of themes was high (mean Kappa = .97). Adherence barriers included MA use, misguided beliefs about ART adherence, memory and planning difficulties, social barriers and perceived stigma, and mental heath issues. Facilitators of effective ART adherence were cognitive compensatory strategies, promotion of well-being, health-care supports, adherence education, and social support. Additionally, the focus groups generated content for reminder text messages to be used in the medication adherence intervention. This qualitative study demonstrates the feasibility of using focus groups to derive patient-centered intervention content to address the health challenge at hand in targeted populations.  相似文献   
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National HIV prevalence estimates across sub-Saharan Africa range from less than 1 percent to over 25 percent. Recent research proposes several explanations for the observed variation, including prevalence of male circumcision, levels of condom use, presence of other sexually transmitted infections, and practice of multiple concurrent partnerships. However, the importance of partnership concurrency for HIV transmission may depend on how it affects coital frequency with each partner. The coital dilution hypothesis suggests that coital frequency within a partnership declines with the addition of concurrent partners. Using sexual behavior data from rural Malawi and urban Kenya, we investigate the relationship between partnership concurrency and coital frequency, and find partial support for the coital dilution hypothesis. We conclude the paper with a discussion of our findings in light of the current literature on concurrency.  相似文献   
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Described here is a new method for determination of carotid–femoral pulse wave velocity (PWV) based on arterial diameter waveform recording by an ultrasound system. The study was carried out on 120 consecutive patients. Carotid–femoral PWV was determined using a tonometric technique (PWVpp, PulsePen, DiaTecne, Milan, Italy) and an echotracking ultrasound system (PWVet, E-Track, Aloka, Tokyo, Japan). The relationship between PWVpp and PWVet was evaluated by linear regression and Bland–Altman analysis. There was excellent agreement between PWVet and PWVpp (Pearson's r = 0.94, 95% confidence interval: 0.91–0.96, p < 0.0001; PWVet = 0.88 × PWVpp + 0.57). The Bland–Altman plot revealed an offset of ?0.33 m/s with limits of agreement from ?2.21 to 1.54 m/s. The coefficients of variation for within-subject repeatability between PWVet and PWVpp had were 5.79% and 8.47%, respectively, without significant differences in the Bland–Altman analysis. The results suggest that echotracking technology can provide a reliable estimate of aortic stiffness comparable to that of the tonometric techniques.  相似文献   
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International Urology and Nephrology - The optimal vitamin D3 therapy for the treatment of secondary hyperparathyroidism (SHPT) in chronic hemodialysis patients is still controversial. Recent...  相似文献   
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