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81.
To investigate the roles specific ruminative styles (brooding and reflection) and hope play in the Integrated Motivational-Volitional (IMV) model of suicidal behavior. Participants were students from a large U.S. state university who were selectively sampled for the experience of recent suicide ideation. Results of a bootstrapped moderated mediation model indicated that defeat had a direct effect on suicide ideation but not an indirect effect on suicide ideation through entrapment. Brooding, but not reflection, strengthened the relationship between defeat and entrapment. Hope weakened the relationship between entrapment and suicide ideation. Implications for the assessment and treatment of suicide risk and future research directions are discussed.  相似文献   
82.
Type 2 diabetes (T2D) disproportionally affects African Americans (AfA) but, to date, genetic variants identified from genome-wide association studies (GWAS) are primarily from European and Asian populations. We examined the single nucleotide polymorphism (SNP) and locus transferability of 40 reported T2D loci in six AfA GWAS consisting of 2,806 T2D case subjects with or without end-stage renal disease and 4,265 control subjects from the Candidate Gene Association Resource Plus Study. Our results revealed that seven index SNPs at the TCF7L2, KLF14, KCNQ1, ADCY5, CDKAL1, JAZF1, and GCKR loci were significantly associated with T2D (P < 0.05). The strongest association was observed at TCF7L2 rs7903146 (odds ratio [OR] 1.30; P = 6.86 × 10−8). Locus-wide analysis demonstrated significant associations (Pemp < 0.05) at regional best SNPs in the TCF7L2, KLF14, and HMGA2 loci as well as suggestive signals in KCNQ1 after correction for the effective number of SNPs at each locus. Of these loci, the regional best SNPs were in differential linkage disequilibrium (LD) with the index and adjacent SNPs. Our findings suggest that some loci discovered in prior reports affect T2D susceptibility in AfA with similar effect sizes. The reduced and differential LD pattern in AfA compared with European and Asian populations may facilitate fine mapping of causal variants at loci shared across populations.Type 2 diabetes (T2D) is a major public health problem affecting 25.8 million people in the U.S. (1). Marked racial differences in its prevalence have been observed, with African American (AfA) adults >40 years of age having nearly twofold higher prevalence than European Americans (27.1 and 15.5%, respectively) (2). In addition to socioeconomic and behavioral risk factors, genetic factors are likely contributors to T2D risk in AfA (3).Genome-wide association studies (GWAS) for T2D and related traits have successfully identified >50 loci with common genetic variants associated with T2D risk in primarily European-descent populations (414) and more recently in East and South Asians (1521). The reported index single nucleotide polymorphisms (SNPs) at these loci have been replicated in multiple populations (2224) but less successfully in AfA (2527). Although differences in environment and lack of study power may partly account for the lack of transferability across ethnicities, differences in linkage disequilibrium (LD) patterns, effect sizes, and risk allele frequency also likely impact the replication of index SNPs. Although the long-range LD in European populations allows for the identification of T2D loci using less dense markers, causal variants are not distinguishable from other nearby SNPs in high LD. This issue prompts the need to examine T2D loci in other populations with different allelic and LD architecture, which may help fine mapping of the underlying functional variants (28).We performed a comprehensive evaluation of the LD region of T2D loci reported in European and Asian GWAS in a meta-analysis of six AfA GWAS. By testing the index and nearby SNPs, we evaluated the transferability of the previously reported loci for T2D association in AfA. We demonstrated that the reduced and differential LD structure in AfA facilitated fine mapping of regions potentially harboring causal variants at some T2D loci.  相似文献   
83.
Abstract

Background/Objective: To determine whether 9 weeks of locomotor training (LT) results in changes in muscle strength and alterations in muscle size and activation after chronic incomplete spinal cord injury (SCI). Study Design: Longitudinal prospective case series.

Methods: Five individuals with chronic incomplete SCI completed 9 weeks of LT. Peak isometric torque, torque developed within the initial 200 milliseconds of contraction (Torque200), average rate of torque development (ARTD), and voluntary activation deficits were determined using isokinetic dynamometry for the knee-extensor (KE) and plantar-flexor (PF) muscle groups before and after LT. Maximum muscle crosssectional area (CSA) was measured prior to and after LT.

Results: Locomotor training resulted in improved peak torque production in all participants, with the largest increases in the more-involved PF (43.9% ± 20.0%), followed by the more-involved KE (21.1% ± 12.3%). Even larger improvements were realized in Torque200 and ARTD (indices of explosive torque), after LT. In particular, the largest improvements were realized in the Torque200 measures of the PF muscle group. Improvements in torque production were associated with enhanced voluntary activation in both the KE and ankle PF muscles and an increase in the maximal CSA of the ankle PF muscles.

Conclusion: Nine weeks of LT resulted in positive alterations in the KE and PF muscle groups that included an increase in muscle size, improved voluntary activation, and an improved ability to generate both peak and explosive torque about the knee and ankle joints.  相似文献   
84.
Abstract

Background: Obstades such as bumps, curb descents, and uneven driving surfaces cause vibrations that affect the wheelchair, and in turn, the wheelchair user. Chronic exposure can cause low-back pain, disk degeneration, and other harmful effects. Little research has been conducted to assess the vibrations experienced by wheelchair users.

Objective: The purpose of this study was to conduct an evaluation of the vibration exposure du ring electric-powered wheelchair driving and mechanical energy requirements for manual wheelchair propulsion over selected sidewalk surfaces. The goal was to determine the criteria for a wheelchair-pedestrian access route that does not require excessive propulsive work or expose wheelchair users to potentially harmful vibrations.

Methods: Ten unimpaired individuals participated in this study. Six sidewalk surfaces were tested. Measured variables included power of the acceleration per octave, mechanical work to propel over surfaces, peak acceleration, and frequency at which peak acceleration occurs.

Results: For both the manual and electric-powered wheelchair, at 1 m/s, significant differences were found in peak accelerations between the seat and footrest (P < 0.0001) and between the sidewalk surfaces (P = 0.004 ). The greatest risk for injury caused by shock and vibration exposure occurs at frequ encies near the natural frequency of seated humans (4-15 Hz). The values for work required to propel over the surfaces tested were not stat istically significantly different. Besides appearance and construction, the only distinguishing characteristic was surface roughness caused by the joints.

Conclusion: When treating the poured concrete sidewalk as the standard, surfaces 2, 3, 5, and 6 compared most favorably in t erms of vibration exposure, whereas surface 4 produced mixed results. Surfaces 2, 3, 5, and 6 yielded results that were similar to the poured concrete sidewalk and could be considered acceptable for wheelchair users. in conclusion, surfaces other than the t raditional poured concrete can be used for pedestrian access routes without adding vibration exposure or reducing propulsion efficiency.  相似文献   
85.
INTRODUCTIONA technique of reconstructing the inguinal ligament using a pedicled fascia lata flap is described.PRESENTATION OF CASEA 62-year-old man was referred with massive bilateral abdominal wall hernias, following numerous attempts at repair and subsequent recurrences. There was complete absence of the right inguinal ligament.The inguinal ligament was reconstructed using a strip of fascia lata, pedicled on the anterior superior iliac spine. This was transposed to cover the external iliac vessels, and sutured to the pubic tubercle. The musculoaponeurotic abdominal wall was reconstructed with two 20 cm × 20 cm sheets of porcine acellular dermal matrix and an overlying sheet of polypropylene mesh, sutured to the remaining abdominal wall muscles laterally, and to both inguinal ligaments. The cutaneous abdominal wall was closed with an abdominoplasty technique.The reconstruction has remained intact nine months following surgery.DISCUSSIONComplete destruction of the inguinal ligament is rare but can occur following multiple operative procedures or trauma. To date, the only published reports of inguinal ligament reconstruction have been performed using synthetic mesh. The use of autologous tissue should reduce the risk of erosion into the neurovascular bundle, seroma formation, and enhance integration into surrounding tissues.CONCLUSIONThis new technique for autologous reconstruction of the inguinal ligament provides a safe alternative to the use of synthetic mesh in the operative armamentarium of plastic and hernia surgeons.  相似文献   
86.
This article uses bioethical and cross-cultural lenses to examine the narratives of 11 mental health professionals (psychiatrists, psychologists, and counselors) regarding their perceptions of, and experiences in providing mental health services in Kuwait. Given that there is no legal ethical body governing mental health service delivery in Kuwait, and that there have been recent reports of negative personal experiences with mental health professionals, this study sought to understand the types of narratives and treatment approaches that may contribute to inadequate service delivery. This study drew on interpretive phenomenological analysis (IPA) and critical discourse analysis in its analysis. The analyses indicated that ideology (either patient-centered or disease-centered) can be shaped by educational background and professional experiences, which can, in turn, shape how mental health professionals deliver mental health services to the Kuwaiti community. Findings also indicate that mainstream western medical discourses are actively transforming the landscape of mental health care in Kuwait; while this western transformation is welcomed (and even imposed) by some clinicians, it is critiqued by others who feel that: a) indigenous forms of healing are beginning to wane; and b) local clinicians can be pressured to assimilate to North American standards of mental health care. Research limitations and directions for clinical education and practice are also discussed.  相似文献   
87.
88.
Objective: We tested associations of the growth factors VEGF, FGF-2, HGF and PDGF-BB with coronary artery calcium scores and cardiovascular events (CVD) in type 2 diabetes mellitus (T2DM). Methods: A cross-sectional study selected 40 frequency matched (by age, gender and race) subjects with T2DM from the first (0–111) and the third (> 1400) coronary artery calcium (CAC) score tertiles in the Diabetes Heart Study (DHS), in which 36 were with and 41 were without history of CVD events. Plasma levels of VEGF, FGF-2, HGF and PDGF-BB were measured in all subjects. Results: None of the growth factors was significantly different between the first and third CAC score tertiles. Mean plasma FGF-2 and PDGF-BB levels were significantly higher in the group without prior CVD events compared with the group with prior CVD events [mean(95%CI): 219.20 (194.42–247.15) vs. 152.93 (135.64–172.43) pg/ml, p = 0.03] and [mean(95%CI): 106.70 (89.12–127.74) vs. 61.56 (50.91–74.44) pg/ml, p = 0.03], respectively. Subgroup analysis in the first CAC tertile showed a significantly higher PDGF-BB levels in those without compared with those with CVD events [mean (95%CI): 208.36 (190.57–228.15) vs. 102.93 (80.64–125.21) pg/ml, p = 0.004]. Conclusion: Plasma growth factor levels were not significantly different between the extremes of CAC scores in T2DM. However, low plasma levels of PDGF-BB and FGF-2 are associated with prior cardiovascular events in T2DM. Studies are needed to confirm our results and also to establish temporality of this association.  相似文献   
89.
90.
Spinal NMDA receptors (NMDA R) are important in neuropathic sensitisation and acute administration of antagonists can provide temporary attenuation of sensitisation. If establishment of the chronic pain state could be prevented by brief administration of such agents at or around the time of nerve injury (pre-emptive analgesia) it might be possible to avoid many of the unacceptable side effects associated with repeated administration of these or other antagonists. Several reports describe aspects of effective pre-emptive analgesia from NMDA R antagonists in animal models of neuropathic pain. The first aim of the present study was to make a direct comparison of changes in mechanical allodynia, cold allodynia and thermal hyperalgesia following nerve injury, demonstrating their increasing degree of susceptibility to pre-emptive NMDA R antagonist treatment. Secondly, we used immunoblotting and immunohistochemistry to investigate the effects of nerve injury on NMDA receptor subunit expression, revealing increased expression of NR2B, but not NR2A and reduced NR1 in the superficial dorsal horn. These changes were attenuated following NMDA receptor antagonist pre-treatment. Thirdly, we investigated the pharmacological properties of residual mechanical allodynia and cold allodynia that remained after pre-emptive treatment and revealed a greater sensitivity to NMDA R antagonists. These findings indicate that in addition to a marked suppression of thermal hyperalgesia and cold allodynia, pre-emptive treatment with NMDA R antagonist causes a lasting change in spinal NMDA R complexes such that remaining mechanical allodynia should be more effectively targeted by NMDA R antagonists.  相似文献   
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