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Three prime repair exonuclease 1 (TREX1) degrades excess HIV-1 DNA, thereby preventing recognition by innate immunity receptors and type I interferon responses. Analyses performed in two HIV-exposed seronegative (HESN) cohorts did not show any differences in TREX1 sequence, single nucleotide polymorphisms frequency, or expression in HESN compared to controls, suggesting that, despite its central role in the HIV-1 infection process, genetic diversity at TREX1 is not a major determinant of susceptibility to infection in humans.  相似文献   
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We used fMRI to explore the extent of the anatomical overlap of three neural systems that the literature on developmental dyslexia associates with reading: the auditory phonological, the visual magnocellular, and the motor/cerebellar systems. Twenty‐eight normal subjects performed four tasks during fMRI scans: word and pseudoword reading, auditory rhyming for letter names, visual motion perception, and a motor sequence learning task. We found that the left occipitotemporal cortex (OTC), which previous studies reported to be dysfunctional in dyslexia, can be fractionated into different functional areas: an anterior and lateral area that was activated by both reading and auditory rhyming tasks; a posterior area that was commonly activated by both the reading and the motion perception task and a medial/intermediate area, including the so‐called Visual Word Form Area, which was specifically activated by the reading task. These results show that the left OTC is an area of segregated convergence of different functional systems. We compared our results with the hypoactivation pattern reported for reading in a previous cross‐cultural PET study on 36 dyslexic subjects from three countries. The region of decreased activation in dyslexia overlapped with regions that are specific for reading and those activated during both the auditory rhyming task and the single word and pseudoword reading task described in the present fMRI study. No overlap was found with the activation patterns for the visual motion perception task or for the motor sequence learning task. These observations challenge current theories of dyslexia. Hum Brain Mapp 34:2669–2687, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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Neuroimaging studies suggest that the cerebellum contributes to human cognitive processing, particularly procedural learning. This type of learning is often described as implicit learning and involves automatic, associative, and unintentional learning processes. Our aim was to investigate whether cerebellar transcranial direct current stimulation (tDCS) influences procedural learning as measured by the serial reaction time task (SRTT), in which subjects make speeded key press responses to visual cues. A preliminary modeling study demonstrated that our electrode montage (active electrode over the cerebellum with an extra-cephalic reference) generated the maximum electric field amplitude in the cerebellum. We enrolled 21 healthy subjects (aged 20–49 years). Participants did the SRTT, a visual analogue scale and a visual attention task, before and 35 min after receiving 20-min anodal and sham cerebellar tDCS in a randomized order. To avoid carry-over effects, experimental sessions were held at least 1 week apart. For our primary outcome measure (difference in RTs for random and repeated blocks) anodal versus sham tDCS, RTs were significantly slower for sham tDCS than for anodal cerebellar tDCS (p?=?0.04), demonstrating that anodal tDCS influenced implicit learning processes. When we assessed RTs for procedural learning across the one to eight blocks, we found that RTs changed significantly after anodal stimulation (interaction “time”?×?“blocks 1/8”: anodal, p?=?0.006), but after sham tDCS, they remained unchanged (p?=?0.094). No significant changes were found in the other variables assessed. Our finding that anodal cerebellar tDCS improves an implicit learning type essential to the development of several motor skills or cognitive activity suggests that the cerebellum has a critical role in procedural learning. tDCS could be a new tool for improving procedural learning in daily life in healthy subjects and for correcting abnormal learning in neuropsychiatric disorders.  相似文献   
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The factors which contribute to an exaggerated blood pressure response (EBPR) during the exercise treadmill test (ETT) are not wholly understood. The association between the insertion/deletion polymorphisms of the angiotensin-converting enzyme (ACE) and M235T of the angiotensinogen with EBPR during ETT still remains unstudied. To identify and compare the risk factors for hypertension between normotensive subjects with EBPR and those who exhibit a normal curve of blood pressure (BP) during ETT. In a series of EBPR cases from a historical cohort of normotensive individuals, a univariate analysis was performed to estimate the association of the studied factors with BP behavior during ETT. Additionally, logistic multivariate regression was conducted to analyze the joint effects of the variables. P-values above 0.05 were considered statistically significant. From a total of 10,027 analyzed examinations, only 219 met the criteria employed to define EBPR, which resulted in a prevalence of 12.6%. For the systolic component of the BP, hyperreactive subjects displayed a mean age and body mass index (BMI) significantly higher than the others (P=0.002 and <0.001, respectively). No association was observed between the polymorphisms cited above and EBPR. An analysis of the joint effect of variables has indicated that only age (P< 0.001) and BMI (P=0.001) were specifically associated with systolic BP during exercise. Age and BMI were the only factors that independently influenced EBPR during ETT.  相似文献   
78.
Many countries with heavy HIV and alcohol burdens do not fully recognize these epidemics as intrinsically interconnected. Missed opportunities for synergistic prevention and treatment of HIV and alcohol abound.Few HIV policies, services for HIV prevention or research projects adequately address alcohol-HIV harms or include alcohol use as an HIV risk factor.  相似文献   
79.
ObjectivesTo compare the occurrence of depression, anxiety, self body image perception, sleep disturbances, and diminished quality of life in prostate cancer patients undergoing adjuvant androgen-deprivation therapy (ADT) as opposed to patients in follow-up alone.Methods and materialsHospital Anxiety and Depression Scale, Pittsburgh Sleep Quality Index, Restless Legs Syndrome Study Group essential diagnostic criteria, Body Image Scale and Functional Assessment of Cancer Therapy Prostate were administered to consecutive prostate cancer patients who underwent radical prostatectomy or radiation therapy and are presently either under adjuvant ADT or included in a follow-up program.ResultsOf the 103 patients enrolled, 49 (47.6%) were receiving adjuvant ADT and 54 (52.4%) were not. Compared with the controls, the patients undergoing ADT showed higher levels of depression (P = 0.002), worse self body image perception (P = 0.001), worse quality of life (P = 0.0001) and worse sleep quality (P = 0.04). ADT was significantly associated with depression at multivariate analysis after adjustment for age, stage, Gleason score, as well as demographic and social variables (P = 0.001). Depression scores showed a strong inverse correlation with quality of life scores (P < 0.01).ConclusionsAdjuvant ADT is associated with depression, worse quality of life, and altered self body image in prostate cancer patients.  相似文献   
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