Virginia Commonwealth University

About: Virginia Commonwealth University is a education organization based out in Richmond, Virginia, United States. It is known for research contribution in the topics: Population & Health care. The organization has 23822 authors who have published 49587 publications receiving 1787046 citations. The organization is also known as: VCU.

What is the source of chronic low back pain and does age play a role

Abstract: Objective. The objective of this study was to estimate the prevalence, mean age, and association of prevalence and age of lumbar internal disc disruption (IDD), facet joint pain (FJP), sacroiliac joint pain (SIJP), spinal and pelvic insufficiency fractures, interspinous ligament injury/Baastrup's Disease, and soft tissue irritation by fusion hardware. Design. The study's design was a retrospective chart review. Setting. The study was set in an academic spine center. Patients. A total of 378 cases from 358 patients were reviewed of which 170 cases from 156 patients who underwent diagnostic procedures were included. Interventions. Discography, dual diagnostic facet joint blocks, intra-articular sacroiliac joint injections, anesthetic injections of painful interspinous ligaments/opposing spinous processes/posterior fusion hardware, or percutaneous augmentation were performed. Outcome Measures. Prevalence and age were analyzed for each diagnosis group. Methods. Patients with recalcitrant low back pain underwent diagnostic procedures based on their clinical presentation until the pain source was identified. Results. The prevalence of internal disc disruption, facet joint pain and sacroiliac joint pain was 42%, 31%, and 18%, respectively. Patients with internal disc disruption were significantly younger than those with facet joint pain or sacroiliac joint pain. Increased age was associated with a decreased probability of internal disc disruption and increased probabilities of facet joint pain and sacroiliac joint pain as the source of low back pain until approximately age 70. Conclusion. Our data confirm the intervertebral disc as the most common etiology of chronic low back pain in adults. Based on our sample, the younger the patient, the more likely low back pain is discogenic in origin. Facetogenic or sacroiliac joint pain is more likely in older patients.

Tailoring tissue engineering scaffolds using electrostatic processing techniques: a study of poly(glycolic acid) electrospinning

Abstract: Poly(glycolic acid) (PGA) has long been a popular polymer in the tissue engineering field. PGA possesses many favorable properties such as biocompatibility, bioabsorbability, and tensile strength. The traditional fiber formation techniques of melt extrusion and cold-drawing are generally limited to fibers of 10–12 μm in diameter. Electrostatic spinning, or electrospinning, is an attractive approach for the production of much smaller diameter fibers which are of interest as tissue engineering scaffolds. We demonstrate the ability to control the fiber diameter of PGA as a function of solution concentration and fiber orientation, as well as show a correlation between the fiber orientation, elastic modulu, and strain to failure of PGA in a uniaxial model.

Genetic and Environmental Influences on Alcohol, Caffeine, Cannabis, and Nicotine Use From Early Adolescence to Middle Adulthood

Abstract: Context While both environmental and genetic factors are important in the etiology of psychoactive substance use (PSU), we know little of how these influences differ through development. Objective To clarify the changing role of genes and environment in PSU from early adolescence through middle adulthood. Design Retrospective assessment by life history calendar, with univariate and bivariate structural modeling. Setting General community. Participants A total of 1796 members of male-male pairs from the Virginia Adult Twin Study of Psychiatric and Substance Use Disorders. Main Outcome Measures Levels of use of alcohol, caffeine, cannabis, and nicotine recorded for every year of the respondent's life. Results For nicotine, alcohol, and cannabis, familial environmental factors were critical in influencing use in early adolescence and gradually declined in importance through young adulthood. Genetic factors, by contrast, had little or no influence on PSU in early adolescence and gradually increased in their effect with increasing age. The sources of individual differences in caffeine use changed much more modestly over time. Substantial correlations were seen among levels of cannabis, nicotine, and alcohol use and specifically between caffeine and nicotine. In adolescence, those correlations were strongly influenced by shared effects from the familial environment. However, as individuals aged, more and more of the correlation in PSU resulted from genetic factors that influenced use of both substances. Conclusions These results support an etiologic model for individual differences in PSU in which initiation and early patterns of use are strongly influenced by social and familial environmental factors while later levels of use are strongly influenced by genetic factors. The substantial correlations seen in levels of PSU across substances are largely the result of social environmental factors in adolescence, with genetic factors becoming progressively more important through early and middle adulthood.

The bright side of being blue: depression as an adaptation for analyzing complex problems.

Abstract: Depression ranks as the primary emotional problem for which help is sought Depressed people often have severe, complex problems, and rumination is a common feature Depressed people often believe that their ruminations give them insight into their problems, but clinicians often view depressive rumination as pathological because it is difficult to disrupt and interferes with the ability to concentrate on other things Abundant evidence indicates that depressive rumination involves the analysis of episode-related problems Because analysis is time consuming and requires sustained processing, disruption would interfere with problem-solving The analytical rumination (AR) hypothesis proposes that depression is an adaptation that evolved as a response to complex problems and whose function is to minimize disruption of rumination and sustain analysis of complex problems It accomplishes this by giving episode-related problems priority access to limited processing resources, by reducing the desire to engage in distracting activities (anhedonia), and by producing psychomotor changes that reduce exposure to distracting stimuli Because processing resources are limited, the inability to concentrate on other things is a tradeoff that must be made to sustain analysis of the triggering problem The AR hypothesis is supported by evidence from many levels, including genes, neurotransmitters and their receptors, neurophysiology, neuroanatomy, neuroenergetics, pharmacology, cognition and behavior, and the efficacy of treatments In addition, we address and provide explanations for puzzling findings in the cognitive and behavioral genetics literatures on depression In the process, we challenge the belief that serotonin transmission is low in depression Finally, we discuss implications of the hypothesis for understanding and treating depression