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Brenda W Gillespie

Publications and source records attributed to Brenda W Gillespie.

27 records · Page 2Linked to original sources
PubMed2003

Strain-specific modification of lethality in fucose-deficient mice.

The FX locus encodes an essential enzyme in the de novo pathway of GDP-fucose biosynthesis. Mice homozygous for a targeted mutation of the FX gene manifest a host of pleiotropic abnormalities including a lethal phenotype that is almost completely penetrant in heterozygous intercrosses on a mixed genetic background. Here we have investigated genetic suppression of FX-mediated lethality. Reduced recovery of heterozygous mice was observed while backcrossing the null FX allele to C57BL/6J (B6), but was less dramatic in an outcross to CASA/Rk and absent in an outcross to 129S1/SvImJ, indicating that genetic background modifies survival of FX+/- progeny. Substantial strain-specific differences in pre- and postnatal survival of FX-/- progeny were also detected in heterozygous crosses of C57BL/6J congenic, 129S1B6F1, and B6CASAF1 mice. Specifically, intrauterine survival of FX-/- mice was greatly increased during a heterozygous intercross on a uniform C57BL/6J genetic background compared with survival on a hybrid genetic background consisting of a mixture of C57BL/6J and 129S2/SvPas. In addition, statistically significant clustering of FX-/- progeny into litters and specific breeding cages was noted during a B6CASAF1 FX+/- intercross, suggesting a rare mechanism for modifier gene action in which parentally expressed genes define the phenotype, in this case the survival potential, of mutant offspring. Our results disclose that lethality in FX mutant mice is determined by one or more strain-specific modifier loci.

Alleles↗
PubMed2003

Creation, cannulation and survival of arteriovenous fistulae: data from the Dialysis Outcomes and Practice Patterns Study.

BACKGROUND: An arteriovenous (A-V) fistula is the optimal vascular access for hemodialysis. The National Kidney Foundation Dialysis Outcomes Quality Initiative (DOQI) recommends that fistulae should mature for at least one month before cannulation, but this recommendation is not evidence-based. If fistulae are created prior to ESRD and cannulation is possible earlier without compromising fistula survival, the need for temporary catheters would be reduced. METHODS: Prospective observational data were analyzed for a random sample (N = 3674) of incident patients at the time of initiating hemodialysis, hemofiltration or hemodiafiltration in 309 facilities in France, Germany, Italy, Japan, Spain, the United Kingdom, and the United States, taking part in the Dialysis Outcomes and Practice Patterns Study (DOPPS). RESULTS: Although the proportion of patients who had pre-dialysis care by a nephrologist differed little between countries, there were large variations in the proportion of patients who commenced hemodialysis via an A-V fistula, A-V graft or central venous catheter. The usual time interval between referral and creation of A-V fistulae also differed greatly between countries. For new hemodialysis (HD) patients initiating HD with an A-V fistula (N = 894) the following results were observed: (1). median time to first cannulation varied greatly between countries: Japan and Italy (25 and 27 days), Germany (42 days), Spain and France (80 and 86 days), UK and US (96 and 98 days). (2). No association was found between cannulation 28 days for patient characteristics of age, gender, and fifteen different classes of patient co-morbid factors. (3). Risk of A-V fistula failure was increased for incident patients who had a prior temporary access [relative risk (RR) = 1.81, P = 0.01] or who were female (RR = 1.52, P = 0.02). (4). Cannulation 14 days. (5) No significant difference in A-V fistula failure was seen for fistulae cannulated in 15 to 28 days compared with 43 to 84 days. CONCLUSION: Significant differences in clinical practice currently exist between countries regarding the creation of A-V fistulae prior to starting hemodialysis and the timing of initial cannulation. Cannulation within 14 days of creation is associated with reduced long-term fistula survival. Fistulae ideally should be left to mature for at least 14 days before first cannulation.

Adolescent↗
PubMed2003

The collaborative initial glaucoma treatment study: baseline visual field and test-retest variability.

PURPOSE: To compare the baseline Collaborative Initial Glaucoma Treatment Study (CIGTS) visual field (VF) score and mean deviation (MD), investigate test-retest variability, and identify variables associated with VF loss and VF measurement variability. METHODS: Baseline data from a randomized clinical trial of 607 patients with newly diagnosed open-angle glaucoma were collected at 14 clinical centers. The CIGTS VF score and MD were obtained from 24-2 VF tests (Zeiss-Humphrey Systems, Dublin, CA) at two visits approximately 2 weeks apart. RESULTS: Although most baseline CIGTS VF scores showed limited field loss, 15% (91/607) of patients showed a substantial deficit (VF score >10 on a 0-20 scale). A small but significant learning effect was seen over the two baseline measures for CIGTS VF score and MD. CIGTS VF score and MD correlate highly (r = -0.93); both have high test-retest correlation (0.83 and 0.91, respectively). Variables associated with greater baseline VF loss for both CIGTS VF score and MD include (probabilities for VF only): male sex (P = 0.018), black race (P <or= 0.0001), lower visual acuity (P <or= 0.0001), higher intraocular pressure if more than 30 mm Hg (P = 0.0034), poor field reliability score (P <or= 0.0001), cardiovascular disease (P = 0.015), reduced patient-reported alertness (P = 0.023), and CIGTS clinical center (P <or= 0.0001). Predictors of increased CIGTS VF score variability include a midrange VF score (P <or= 0.0001), first-tested eye (P = 0.0027), reduced patient-reported alertness (P = 0.0177), increasing age (P = 0.0040), current smoker (P = 0.0014), and CIGTS clinical center (P = 0.0215). CONCLUSIONS: The CIGTS VF score provides a measure of VF strikingly similar to the MD. Variables associated with VF loss and VF variability may help identify patients who need greater clinical scrutiny.

Adult↗
PubMed2002

Donor characteristics associated with reduced graft survival: an approach to expanding the pool of kidney donors.

BACKGROUND: Availability of cadaveric kidneys for transplantation is far below the growing need, leading to longer waiting time and more deaths while waiting. METHODS: Using national data from 1995 to 2000, we evaluated graft survival by donor characteristics and the rate of discard of retrieved organs, with the goal of increasing use of kidneys that are associated with increased risk of graft failure, that is, expanded donor kidneys. RESULTS: Cox models identified four donor factors that independently predicted significantly higher relative risk of graft loss compared with a low-risk group. These factors included donor age, cerebrovascular accident as the cause of death, renal insufficiency (serum creatinine >1.5 mg/dL), and history of hypertension. Expanded donor kidneys were defined as those with relative risk of graft loss greater than 1.70 and included all donors aged 60 years and older and those aged 50 to 59 years with at least two of the other three conditions (cerebrovascular cause of death, renal insufficiency, hypertension). The expanded donor group accounted for 14.8% of transplanted kidneys. Among organs procured from expanded donors, 38% were discarded versus 9% for all other kidneys. The risk of graft loss of expanded donor kidneys was increased in both older and younger recipients but to a greater extent in those recipients older than 50 years. CONCLUSION: By identifying donor factors associated with graft failure, these analyses may help to expand the number of transplanted kidneys by increasing the utilization of retrieved cadaveric kidneys.

Adolescent↗
PubMed2002

Does access to health care impact survival time after diagnosis of AIDS?

Lack of access to health care is often blamed for poor health outcomes, but this effect is not supported by existing HIV/AIDS literature. The authors examined the association between access to care and survival time after progression to AIDS, using survival analysis methods. This study combined data from two CDC sponsored studies of HIV-infected persons, a cross-sectional interview study and a longitudinal medical record review study. Study subjects included 752 persons who progressed to AIDS before December 31, 1999, and were patients at either of two major HIV care facilities in Detroit, MIchigan. Separate statistical models were used to test associations between survival time after meeting the criteria for AIDS and two indicators of access to health care: (1) perceived access to health care and (2) health care utilization patterns. Perceived access was not associated with survival time after AIDS, but patterns of health care utilization were significantly associated with survival time after AIDS (HR = 2.04, p < 0.001). Individuals who received a greater proportion of their care in the ER had a worse survival prognosis than those who received more of their health care in an outpatient clinic setting. It is crucial that we provide HIV-infected populations with tools that enable them to access a regular source of health care.

Acquired Immunodeficiency Syndrome↗
PubMed2002

Periodontitis in the United States: beyond black and white.

OBJECTIVES: This paper examines whether historical disparities in periodontal status between African Americans and whites in the United States have increased, decreased, or remained the same over the 15-year period between the First National Health and Nutrition Examination Survey (NHANES I, 1971-74) and the Third National Health and Nutrition Examination Survey (NHANES III, 1988-94). METHODS: This study compared the magnitude of the relative and absolute differences in the periodontal status of African-American and white adults in NHANES I and again in NHANES III. RESULTS: The prevalence of periodontitis in the US adult population in NHANES I was 31.6 percent, with African Americans exhibiting higher prevalence than whites. In NHANES III, using a different case-definition for periodontitis, the overall prevalence was 11.9 percent, with African Americans again exhibiting higher prevalence than whites. The magnitude of the intrasurvey relative and absolute differences between African Americans and whites increased between NHANES I and NHANES III. This finding remained after adjustment in the logistic regression analyses. After adjustment for all covariates in the model, African Americans were more likely to exhibit periodontitis than whites in both NHANES I (odds ratio [OR] = 1.31; 95% confidence intervals [CI] = .78, 2.19) and NHANES III (OR = 2.09; 95% CI = 1.68, 2.60). However, the CI included 1.00 in NHANES I. CONCLUSIONS: Disparities in periodontitis between African Americans and whites are pervasive and have increased over time. This increase appears to be driven by social, cultural, and behavioral factors.

Adolescent↗
PubMed2002

The prognostic role of the ECG in primary pulmonary hypertension.

BACKGROUND/RATIONALE: Doppler echocardiography and invasive hemodynamic parameters reflective of right ventricular failure are associated with a poor prognosis in patients with primary pulmonary hypertension (PPH). The aims of the present study were to examine whether ECG features in patients with PPH are associated with a decrease in survival, and to determine the value of the ECG in risk stratification. METHODS/RESULTS: We analyzed the ECG, New York Heart Association (NYHA) class, and hemodynamic parameters in 51 untreated patients with PPH (88% women; mean age, 41.7 years; 79% NYHA classes III and IV) evaluated between 1992 and 1998. Subsequent treatment included epoprostenol in 37 patients, calcium channel blockers in 10 patients, epoprostenol and atrial septostomy in 2 patients, and lung transplant in 3 patients. As of 1999, 16 patients had died. Based on Kaplan-Meier estimates, median survival was > 6.5 years and estimated survival at 1 year, 3 years, and 5 years was 86%, 71%, and 57%, respectively. Significant predictors of decreased survival by Cox regression analysis include pulmonary vascular resistance (PVR; hazard ratio [HR], 1.11 per Wood unit), cardiac index (HR, 0.22 per L/min/m(2)), p wave amplitude in lead II (HR, 3.06 per mm), p > or = 0.25 mV in lead II (HR, 2.77), qR in V(1) (HR, 3.55), and World Health Organization criteria for right ventricular hypertrophy (HR, 4.26). After controlling for PVR, the HRs attributable to the ECG criteria were only slightly diminished. NYHA class and pulmonary artery pressures did not correlate with a decrease in survival. CONCLUSIONS: ECG parameters reflective of physiologic and anatomic abnormalities in the right ventricle are associated with decreased survival in patients with PPH, and may be useful for deciding therapeutic choices including the timing for lung transplantation listing.

Adult↗
PubMed2002

Is there homogeneity in periodontal health between African Americans and Mexican Americans?

OBJECTIVES: This study identified and contrasted prevalence and predictors of periodontitis among African Americans, Mexican Americans, and non-Hispanic Whites in the US adult population. DESIGN: Cross-sectional study. This study compared those with and without periodontitis in each racial/ethnic group. METHODS: This study was limited to records of US African-American, Mexican-American, and non-Hispanic White adults at least 17 years of age who received a complete periodontal assessment as part of the dental examination in the third National Health and Nutrition Examination Survey (1988-1994). RESULTS: Despite the findings that Mexican Americans were less educated, poorer, and had less insurance coverage than African Americans, Mexican Americans had a similar prevalence of periodontitis as non-Hispanic Whites. African Americans had the highest prevalence among all groups. A similar scenario was observed in the multiple logistic analyses. CONCLUSIONS: Mexican Americans had periodontal health profiles closer to non-Hispanic Whites than did African Americans, despite the shared "minority" status. Public health research and practice should explicitly recognize that while "minorities" are considered a homogeneous group, they do not necessarily share the same health profiles.

Adolescent↗