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Gary Rubin

Publications and source records attributed to Gary Rubin.

5 recordsLinked to original sources
PubMed2005

Visual acuity change and mortality in older adults.

PURPOSE: Several studies indicate an increased mortality rate in older adults who have visual impairment, but few have attempted to address a potential causal mechanism. The goals of this study are to determine whether visual acuity loss increases the risk of dying and to examine whether depressive symptoms act as a mediator in this relationship. METHODS: Data were derived from the 2520 older adults who participated in the Salisbury Eye Evaluation project, a population-based prospective 8-year cohort study. Presenting binocular visual acuity was measured with the Early Treatment Diabetic Retinopathy Study [ETDRS] eye chart and depressive symptoms with the General Health Questionnaire Part D subscale. Mortality data were collected by staff follow-up. Analyses were performed with the Cox proportional hazards regression. RESULTS: Worse baseline acuity was associated with a higher mortality rate (hazard ratio [HR] = 1.05; 95% confidence interval [CI], 1.01-1.09). Also, those who gained two or more lines of visual acuity over 2 years had a lower adjusted risk of dying (HR = 0.47; 95% CI, 0.23-0.95). An interaction was detected, in that women who lost > or =3 lines of visual acuity over a 2-year period had a higher adjusted risk of dying (HR = 3.97; 95% CI, 2.21-7.15), whereas men did not (HR = 1.32; 95% CI, 0.66-2.63). Depressive symptoms did not mediate these relationships. CONCLUSIONS: If the relationship between visual acuity and mortality is indeed causal, it most likely acts via numerous pathways through a variety of intervening variables. The identification of these intervening variables could give additional targets for intervention if acuity cannot be restored.

Aged↗
PubMed2003

Orthopaedic malpractice claims in the VA medical system.

This study was undertaken to delineate the outcome of orthopaedic malpractice claims in the Veterans Affairs Medical Center (VAMC) system compared with the private sector. All orthopaedic administrative tort (malpractice) claims handled by the Office of Regional Counsel in Nashville, Tennessee during the 5-year period (8/93-7/98) were analyzed. Attention was directed at: 1) the number and type of claims, 2) the disposition of the claims, 3) the average award or settlement and range in size of awards (indemnity), and 4) the length of time required to process and dispose of each claim. These data were compared to those compiled in that segment of the private sector represented in the database of Physician Insurers Association of America (PIAA) for a similar five years (1/90-12/94). Twenty-six claims were filed in the 5-year study period and 22 were adjudicated by December 1999. Fourteen of 22 (64%) were defended successfully and eight (36%) resulted in an award to the claimant plaintiff. In the private sector those figures were 69% and 31%, respectively. The VAMC average indemnity was 20,404 dollars (range, 3500-100,000 dollars) versus 145,200 dollars in the private sector. Approximately 1% of all awards in the private sector were greater than 1,000,000 dollars. The length of time required by the VAMC to process and dispose of each claim ranged from 6 to 59 months and averaged 15.2 months. The settlement rate of orthopaedic medical malpractice claims involving the VAMC and the private sector is similar. It appears that the average award is greater in the private sector. This may reflect more claims and lesser awards in the VAMC. In both systems, most claims do not result in an indemnity.

Arthroplasty↗
PubMed2002

Aromatase--a brief overview.

There is growing awareness that androgens and estrogens have general metabolic roles that are not directly involved in reproductive processes. These include actions on vascular function, lipid and carbohydrate metabolism, as well as bone mineralization and epiphyseal closure in both sexes. In postmenopausal women, as in men, estrogen is no longer solely an endocrine factor but instead is produced in a number of extragonadal sites and acts locally at these sites in a paracrine and intracrine fashion. These sites include breast, bone, vasculature, and brain. Within these sites, aromatase action can generate high levels of estradiol locally without significantly affecting circulating levels. Circulating C19 steroid precursors are essential substrates for extragonadal estrogen synthesis. The levels of these androgenic precursors decline markedly with advancing age in women, possible from the mid-to-late reproductive years. This may be a fundamental reason why women are at increased risk for bone mineral loss and fracture, and possibly decline of cognitive function, compared with men. Aromatase expression in these various sites is under the control of tissue-specific promotors regulated by different cohorts of transcription factors. Thus in principle, it should be possible to develop selective aromatase modulators (SAMs) that block aromatase expression, for example, in breast, but allow unimpaired estrogen synthesis in other tissues such as bone.

Animals↗
PubMedDate not supplied

Clinical impact of double protease inhibitor boosting with lopinavir/ritonavir and amprenavir as part of salvage antiretroviral therapy.

PURPOSE: Double protease inhibitor (PI) boosting is being explored as a new strategy in salvage antiretroviral (ARV) therapy. However, if a negative drug interaction leads to decreased drug levels of either or both PIs, double PI boosting could lead to decreased virologic response. A negative drug interaction has been described between amprenavir (APV) and lopinavir/ritonavir (LPV/r). This observational cohort study assessed the virologic impact of the addition of APV to a salvage ARV regimen, which also contains LPV/r, compared to a regimen containing LPV/r alone. METHOD: Patients initiated on a salvage ARV regimen that included LPV/r obtained from the expanded access program in Toronto, Canada, were evaluated. APV (600-1,200 mg bid) was added at the discretion of the treating physician. RESULTS: Using multivariate Cox proportional hazards models, we found that the addition of APV to a LPV/r-containing salvage regimen was not significantly associated with time to virologic suppression (< 50 copies/mL; adjusted hazard ratio [HR] = 0.75, p =.12) or with time to virologic rebound (adjusted HR = 1.46, p =.34). Those patients who received higher doses of APV had an increased chance of virologic suppression (p =.03). In a subset of 27 patients, the median LPV C(trough) was significantly lower in patients receiving APV (p =.04), and the median APV C(trough) was reduced compared to reported controls. CONCLUSION: Our data do not support an additional benefit in virologic reduction of double boosting with APV and LPV/r relative to LPV/r alone in salvage ARV therapy. Our study's limitations include its retrospective nature and the imbalance between the two groups potentially confounding the results. Although these factors were adjusted for in the multivariate analysis, a prospective randomized controlled trial is warranted to confirm our findings.

Adult↗