Biomedical subjects

Sarah Worley

Publications and source records attributed to Sarah Worley.

13 recordsLinked to original sources

PubMed2006

Role of total antioxidant capacity in the differential growth of human embryos in vitro.

OBJECTIVE: The objective of this study was to examine the relationship of early human embryonic development parameters with day 1 culture media total antioxidant levels (day 1 TAC). DESIGN: Prospective study. SETTING: Patients undergoing assisted reproduction (ART) in a teaching hospital. PATIENT(S): Patients undergoing conventional IVF (n = 153; 167 cycles) and intracytoplasmic sperm injection (ICSI; n = 105; 116 cycles) were included. Both fertilization and early cultures were performed in human tubal fluid (HTF) with 5% serum substitute supplement. INTERVENTION(S): Levels of total antioxidants in the central well (sample) and the outer well (control) of each embryo culture dish were measured. MAIN OUTCOME MEASURE(S): Fertilization rate and embryo quality at days 3 and 5 were recorded for each cycle. Age, parity, and demographic features were also compared. RESULT(S): After controlling for all demographic and clinical variables, day 1 TAC was related to fertilization rates in both groups of patients. Day 1 TAC was significantly related to high (>7) day 3 cell number, low (<10%) fragmentation rate, and blastocyst development rate in both conventional IVF and ICSI cycles. Day 1 TAC was related to pregnancy in ICSI but not conventional IVF cycles. CONCLUSION(S): Day1 TAC appears to be an important biochemical marker for early embryonic growth. Decreased embryonic fragmentation, enhanced cleavage rate, and increased blastocyst development rate may be partially related to day 1 TAC in the culture media. Whether this relationship is a cause or effect needs further assessment.

Adult↗

PubMed2006

Quantitative analysis of procalcitonin after pediatric cardiothoracic surgery.

Procalcitonin appears to be an early and sensitive marker of bacterial infection in a variety of clinical settings. The use of levels of procalcitonin to predict infection in children undergoing cardiac surgery, however, may be complicated by the systemic inflammatory response that normally accompanies cardiopulmonary bypass. The aim of our study was to estimate peri-operative concentrations of procalcitonin in non-infected children undergoing cardiac surgery. Samples of serum for assay of procalcitonin were obtained in 53 patients at baseline, 24, 48, and 72 hours following cardiac surgery. Concentrations were assessed using an immunoluminetric technique. Median concentrations were lowest at baseline at less than 0.5 nanograms per millilitre, increased at 24 hours to 1.8 nanograms per millilitre, maximized at 48 hours at 2.1 nanograms per millilitre, and decreased at 72 hours to 1.3 nanograms per millilitre, but did not return to baseline levels. Ratios of concentrations between 24, 48 and 72 hours after surgery as compared to baseline were 6.15, with 95 percent confidence intervals between 4.60 and 8.23, 6.49, with 95 percent confidence intervals from 4.55 to 9.27, and 4.26, with 95 percent confidence intervals between 2.78 and 6.51, respectively, with a p value less than 0.001. In 8 patients, who had no evidence of infection, concentrations during the period from 24 to 72 hours were well above the median for the group. We conclude that concentrations of procalcitonin in the serum increase significantly in children following cardiac surgery, with a peak at 48 hours, and do not return to baseline within 72 hours of surgery. A proportion of patients, in the absence of infection, had exaggerated elevations post-operatively.

Adolescent↗

PubMed2006

Risks and outcomes of acute kidney injury requiring dialysis after cardiac transplantation.

BACKGROUND: Risk factors for postoperative acute kidney injury (AKI) are well described in nontransplantation settings. Data regarding risks and consequences of AKI after cardiac transplantation are unclear. METHODS: We analyzed 756 cardiac transplant recipients between 1993 and 2004. The primary outcome is postoperative AKI requiring dialysis therapy. Secondary outcomes are hospital mortality and postoperative morbidities, including cardiac, neurological, and serious infection. Wilcoxon rank-sum, chi-square, or Fisher exact tests were used for univariable comparison. A bootstrap-bagging procedure (1,000 repetitions) and multivariable logistic analysis with multiple imputation were used for the final model. RESULTS: AKI frequency was 5.8% (44 of 756 patients). By means of univariable analysis, preoperative risk factors for AKI were diabetes, prior cardiac surgery, intra-aortic balloon pump use, albumin level, creatinine level, clinical severity score, and cold ischemia time. Intraoperative risk factors were cardiopulmonary bypass time and transfusion requirement. By means of multivariate analysis, serum creatinine level (odds ratio [OR], 2.7; 95% confidence interval [CI], 1.6 to 4.6), serum albumin level (OR, 0.34; 95% CI, 0.21 to 0.54), insulin-requiring diabetes (OR, 3.5; 95% CI, 1.4 to 9.0), and cardiopulmonary bypass time (OR, 1.29; 95% CI, 1.02 to 1.64) were independent predictors of postoperative AKI. The overall postoperative mortality rate was 4.2%; it was 50% in patients with AKI compared with 1.4% in patients without AKI. AKI was associated with greater frequencies of cardiac, neurological, and serious infection morbidities (43.2%, 18.2%, and 54.6% versus 5.5%, 2.3%, and 7.2%, respectively; P < 0.001). CONCLUSION: AKI is associated with significant morbidity and mortality after cardiac transplantation. Predictors of AKI can be used to risk-stratify patients to ameliorate further kidney injury and offer a survival benefit.

Acute Kidney Injury↗

PubMed2006

Ribose versus dextrose supplementation, association with rowing performance: a double-blind study.

OBJECTIVE: It has been hypothesized that ribose supplementation rapidly replenishes adenosine triphosphate stores and thereby improves exercise performance. We compared the effects of ribose versus dextrose on rowing performance. DESIGN: Double-blind randomized trial. SETTING: Rowing team training area of large midwestern university. PARTICIPANTS: Thirty-one women collegiate rowers. INTERVENTIONS: We studied the effects of ribose versus dextrose supplementation (10 g each in 8 oz water) for 8 weeks before and after practice and 2000-m time trials. OUTCOME MEASUREMENTS AND RESULTS: In the time trials, the dextrose group showed significantly more improvement at 8 weeks than the ribose group (median, 15.2 vs. 5.2 s; P = 0.031). CONCLUSIONS: We doubt ribose impaired, and hypothesize dextrose enhanced, rowing performance. Further research is needed to define what role, if any, dextrose and ribose play as athletic supplements.

Adult↗

PubMed2006

Immunohistochemical analysis identifies two cyclin D1+ subsets of plasma cell myeloma, each associated with favorable survival.

The significance of cyclin D1 expression in plasma cell myeloma was examined by immunohistochemical analysis using a newly available rabbit monoclonal antibody with superior staining properties. Two patterns of positive staining were observed, each associated with distinct pathologic features. Strong cyclin D1 staining was associated with increased plasma cells at diagnosis (P=.026), lymphoplasmacytic morphologic features (P=.029), CD20 expression (P=.040), and t(11;14)(q13;q32) as detected by interphase fluorescence in situ hybridization with simultaneous CD138 immunofluorescence (P<.001). In contrast, weak staining was associated with hyperdiploidy (P=.02) and gains of the CCND1 locus (P=.01). Overall survival was longer in the cyclin D1+ cases than in cyclin D1- cases (estimated 3-year survival, 73% vs 27%; P=.005). Improved survival was seen in the strongly positive and weakly positive groups compared with cyclin D1- cases (P=.005). This report shows for the first time that cyclin D1 immunohistochemical analysis can provide prognostic information in plasma cell myeloma.

Animals↗

PubMed2005

Effects of short-term glucocorticoids on cardiovascular biomarkers.

CONTEXT: Glucocorticoids are known to acutely increase blood pressure, suppress inflammation, and precipitate insulin resistance. However, the short-term effects of glucocorticoids on other cardiovascular risk factors remain incompletely characterized. OBJECTIVE: Our objective was to determine the effects of a short course of dexamethasone on multiple cardiovascular biomarkers and to determine whether suppression of morning cortisol in response to low-dose dexamethasone is correlated with cardiovascular risk markers in healthy volunteers. DESIGN: We conducted a randomized, double-blind, placebo-controlled study. SETTING: The study took place in a tertiary care hospital. STUDY SUBJECTS: Twenty-five healthy male volunteers, ages 19-39 yr, participated in the study. INTERVENTION: Subjects received either 3 mg dexamethasone twice daily or placebo for 5 d. Subjects also underwent a low-dose (0.5 mg) overnight dexamethasone suppression test. MEASURES: Parameters examined before and after the 5-d intervention included heart rate, blood pressure, weight, fasting lipid variables, homocysteine, renin, aldosterone, insulin resistance (homeostasis model assessment), high-sensitivity C-reactive protein, B-type natriuretic peptide, flow-mediated and nitroglycerin-mediated brachial artery dilatation, and heart rate recovery after exercise. All measurements were done in the morning hours in the fasting state. RESULTS: Dexamethasone increased systolic blood pressure, weight, B-type natriuretic peptide, and high-density-lipoprotein-cholesterol. Dexamethasone decreased resting heart rate, high-sensitivity C-reactive protein, and aldosterone and tended to attenuate nitroglycerin-mediated vasodilatation. There was no effect on flow-mediated vasodilatation, diastolic blood pressure, triglycerides, low-density-lipoprotein-cholesterol, nonesterified fatty acids, homocysteine, or heart rate recovery. The response of circulating cortisol to low-dose dexamethasone had no significant correlation with any of the cardiovascular risk markers. CONCLUSIONS: Short-term glucocorticoids elicits both favorable and unfavorable effects on different cardiovascular risk factors. Manipulation of specific glucocorticoid-responsive physiological pathways deserves further study.

Adult↗

PubMed2005

Influence of renal dysfunction on mortality after cardiac surgery: modifying effect of preoperative renal function.

BACKGROUND: Acute renal failure (ARF) requiring dialysis is an independent risk factor of mortality after cardiac surgery; the level of preoperative renal function influences the risk of both postoperative ARF and mortality. The relationship between mild renal dysfunction and mortality, and the modifying effect of baseline renal function on this association, is less clear. METHODS: We studied 31,677 patients undergoing cardiac surgery between 1993 and 2002. We used a logistic regression model to assess the relationship between postoperative renal dysfunction and mortality, while adjusting for preoperative renal function, postoperative ARF requiring dialysis, and other risk factors. RESULTS: The overall postoperative mortality rate was 2.2% (698/31,677). For the entire cohort, a clinically relevant increase in the adjusted risk of mortality occurred beyond 30% decline in postoperative GFR. The mortality rate was 5.9% (N, 292/4986) among patients who developed 30% or greater decline in postoperative GFR not requiring dialysis versus 0.4% (N, 106/26,136) among those with <30% decline (P < 0.001). A significant interaction between preoperative GFR and percent change in postoperative GFR (P < 0.001) indicated that at equivalent degrees of renal dysfunction, the mortality risk was greater at a lower preoperative GFR. ARF requiring dialysis was strongly associated with mortality in the model (odds ratio 4.2; 95% CI 3.1-5.7). CONCLUSION: Renal dysfunction not requiring dialysis is an independent risk factor of mortality after cardiac surgery. A better preoperative GFR attenuates the effect of postoperative renal dysfunction on mortality; this interaction needs to be considered while defining a clinically relevant threshold of ARF.

Acute Kidney Injury↗

PubMed2004

A clinical score to predict acute renal failure after cardiac surgery.

The risk of mortality associated with acute renal failure (ARF) after open-heart surgery continues to be distressingly high. Accurate prediction of ARF provides an opportunity to develop strategies for early diagnosis and treatment. The aim of this study was to develop a clinical score to predict postoperative ARF by incorporating the effect of all of its major risk factors. A total of 33,217 patients underwent open-heart surgery at the Cleveland Clinic Foundation (1993 to 2002). The primary outcome was ARF that required dialysis. The scoring model was developed in a randomly selected test set (n = 15,838) and was validated on the remaining patients. Its predictive accuracy was compared by area under the receiver operating characteristic curve. The score ranges between 0 and 17 points. The ARF frequency at each score level in the validation set fell within the 95% confidence intervals (CI) of the corresponding frequency in the test set. Four risk categories of increasing severity (scores 0 to 2, 3 to 5, 6 to 8, and 9 to 13) were formed arbitrarily. The frequency of ARF across these categories in the test set ranged between 0.5 and 22.1%. The score was also valid in predicting ARF across all risk categories. The area under the receiver operating characteristic curve for the score in the test set was 0.81 (95% CI 0.78 to 0.83) and was similar to that in the validation set (0.82; 95% CI 0.80 to 0.85; P = 0.39). In conclusion, a score is valid and accurate in predicting ARF after open-heart surgery; along with increasing its clinical utility, the score can help in planning future clinical trials of ARF.

Acute Kidney Injury↗

PubMed2004

Factors associated with early extubation after cardiac surgery in young children.

OBJECTIVE: Children undergoing congenital heart surgery require mechanical ventilation. We sought to identify pre- and intraoperative factors (PrO, IO) associated with successful early extubation <24 hrs. DESIGN AND PATIENTS: We performed a retrospective chart review of children <36 months old who underwent congenital heart surgery from January 1998 to July 1999. SETTING: Pediatric intensive care unit in a children's hospital. MEASUREMENTS: Generalized Estimating Equation models were fit to assess the association between PrO and IO and early extubation while accounting for the correlation between surgeries performed on the same patient. Estimated odds ratios (EOR) and 95% confidence intervals were calculated. Multivariable models were constructed using a forward selection process with inclusion criteria of p<.05. Multivariable models, which included PrO and IO variables, were adjusted for procedure group. The area under the receiver operating characteristic curve was computed for each model. RESULTS: A total of 203 children underwent 219 surgeries; 103 (47%) children were extubated in <24 hrs, with only one (1%) failed extubation. PrO variables associated with successful early extubation included age >6 months (EOR, 6.1), absence of pulmonary hypertension (EOR, 9.1), gestational age >36 wks (EOR, 4.6), and absence of congestive heart failure (EOR, 2.4). IO variables were less likely to be associated with successful early extubation. Our model of PrO variables with multiple factors showed that presence of two factors was associated with an EOR of 4.2 for successful early extubation compared with children with zero or one factor. Presence of three and four factors was associated with an EOR of 18.0 and 76.5, respectively. The area under the receiver operating characteristic curve for this model is 0.816. Incision type, complex vs. simple procedure, and palliative vs. complete repair were not associated with success of early extubation. CONCLUSIONS: Early extubation is possible in many very young children undergoing congenital heart surgery, with a low rate of failed extubation. The model would be improved by prospective validation with larger numbers at multiple institutions.

Female↗

PubMed2003

Renal dysfunction and serious infections after open-heart surgery.

BACKGROUND: Infections and sepsis are important determinants of mortality in patients with renal dysfunction. We studied the influence of preoperative renal function or postoperative acute renal failure (ARF) on the frequency of infections after open-heart surgery. METHODS: This was a retrospective analysis of 24,660 patients undergoing open-heart surgery from 1993 to 2000. Primary outcome was occurrence of serious infections after open-heart surgery; secondary outcome was hospital mortality. RESULTS: Overall incidence of infections after open-heart surgery was 3.3%. The infection rate was higher in patients with lower preoperative creatinine clearance, ranging between 2.2% and 10.0%. Regarding postoperative ARF, the frequency of infections was 58.5% in those patients requiring dialysis vs. 23.7% in those with ARF not requiring dialysis (P < 0.001); within each subgroup, however, the infection rates were similar regardless of the baseline renal function. In patients who did not develop ARF by either of our definitions, the infection rate was 1.6%. By multivariate analysis, preoperative renal function was an independent risk factor associated with infections [odds ratio (OR) for preoperative creatinine>1.2 mg/dL, 1.3; CI, 1.1 to 1.6]. The relationship between preoperative renal function and infection prevailed even after excluding the patients with postoperative ARF. The overall morality was 2.2%; the mortality in patients with serious infection was 31.7%. CONCLUSION: Both preoperative renal dysfunction and postoperative ARF influence the frequency of serious infections after open-heart surgery. The infection rate was higher in patients with postoperative ARF regardless of the baseline renal function. However, preoperative renal dysfunction portended higher risk of infection, independent of the influence of postoperative ARF.

Acute Kidney Injury↗

PubMed2003

Tacrolimus and mycophenolate mofetil provide effective immunosuppression in rat laryngeal transplantation.

OBJECTIVES/HYPOTHESIS: Tacrolimus is efficacious in several transplantation settings. Some studies have demonstrated improved results using combination therapy with mycophenolate mofetil. Our primary objective was to evaluate the efficacy and optimal dosing of tacrolimus in preventing rejection, using an established rat model of laryngeal transplantation. Further, the ability of mycophenolate to allow lower dosing of tacrolimus while achieving equivalent immunosuppression was investigated. STUDY DESIGN: A dosage efficacy study with 10 experimental arms was conducted. METHODS: Dosage groups were 0.1, 0.2, 0.3, and 0.6 mg/kg tacrolimus alone and 0.1 mg/kg tacrolimus combined with 15 mg/kg mycophenolate mofetil, 0.1 mg/kg tacrolimus combined with 30 mg/kg mycophenolate mofetil, 0.1 mg/kg tacrolimus combined with 40 mg/kg mycophenolate mofetil, 0.2 mg/kg tacrolimus combined with 15 mg/kg mycophenolate mofetil, 0.2 mg/kg tacrolimus combined with 30 mg/kg mycophenolate mofetil (30 d only), and 0.2 mg/kg tacrolimus combined with 40 mg/kg mycophenolate mofetil. Each group contained 8 to 10 rats. Grafts were harvested for histopathological analysis on day 15 or 30 after transplantation. Histopathological appearance of the graft was blindly graded according to an established scale. Dosage groups were compared on rejection score using Wilcoxon's rank sum test and the Jonckheere-Terpstra test for trend. RESULTS: There was a significant association between increasing dose of tacrolimus and decreasing rejection score at both 15 and 30 days (P <.001). In the groups treated with 0.1 mg/kg T, an increasing dose of mycophenolate was associated with lower rejection scores at both 15 and 30 days (P =.001). In the group treated with 0.2 mg/kg T, there was no evidence that the addition of mycophenolate resulted in lower rejection at 15 days. However, at 30 days, combination therapy with increasing doses of mycophenolate was associated with decreasing rejection score (P =.002). CONCLUSIONS: Tacrolimus is an effective immunosuppressive agent for laryngeal transplantation. Mycophenolate mofetil allows lower doses of tacrolimus to be used while preserving graft viability in the early post-transplantation period.

Animals↗

PubMed2002

Outcome of laparoscopic radical and open partial nephrectomy for the sporadic 4 cm. or less renal tumor with a normal contralateral kidney.

PURPOSE: Nephron sparing surgery provides effective therapy in patients with a solitary sporadic renal tumor 4 cm. or less and a normal contralateral kidney. Laparoscopic radical nephrectomy has been applied as a newer alternative therapy in these patients. These 2 contemporary approaches represent divergent treatment alternatives at centers where laparoscopic nephron sparing surgery is not offered. We compared the short-term and long-term impact of these 2 treatment modalities in patients with a sporadic localized solitary renal tumor 4 cm. or less and a normal opposite kidney. MATERIALS AND METHODS: A retrospective review of a contemporary series of patients (1996 to 2001) who underwent open nephron sparing surgery and met study inclusion criteria was performed and compared with a similar cohort (1997 to 2001) that underwent laparoscopic radical nephrectomy. Only patients with a single renal tumor of 4 cm. or less, normal serum creatinine less than 1.5 mg./dl. and a normal contralateral kidney were included in analysis. The 2 groups were compared in regard to demographic, clinical and pathological variables using parametric and nonparametric tests. Linear regression analysis was done to compare the percent change in serum creatinine, while adjusting for demographic and clinical variables, and followup. RESULTS: A total of 35 patients who underwent laparoscopic radical nephrectomy and 82 who underwent open nephron sparing surgery met study inclusion criteria. Mean patient age in the laparoscopic group was significantly greater (67.3 versus 56.2 years, p <0.001), mean American Society of Anesthesiologists class score was higher (p = 0.04) and mean tumor size was greater (3.1 versus 2.6 cm., p = 0.003) than in the nephron sparing group. The laparoscopic group had significantly decreased mean blood loss (100 versus 200 ml., p <0.001), hospital stay (1 versus 5 days, p <0.001), narcotic use (16.5 versus 224 mg., p <0.001) and operative time (184.4 versus 216.2 minutes, p <0.007) compared with the nephron sparing group. Patients who underwent nephron sparing surgery experienced less postoperative deterioration in renal function, as measured by the percent increase in serum creatinine postoperatively (0% versus 25%, p <0.001). The results of regression analyses at 4 and 6 months of followup indicated that open nephron sparing surgery is associated with significantly lower serum creatinine than laparoscopic radical nephrectomy after adjusting for demographic and clinical variables, and followup. CONCLUSIONS: Open nephron sparing surgery and laparoscopic radical nephrectomy are relatively recent and significant developments for treating patients with renal cell carcinoma and they represent accepted standards of care in those with a small renal mass and normal contralateral kidney. In patients presenting with a sporadic solitary renal tumor of 4 cm. or less and a normal contralateral kidney the significant short-term and intermediate term benefits of the laparoscopic approach must be weighed against the long-term advantage of better renal function associated with open nephron sparing surgery. The distinct advantages of these 2 approaches may ultimately be realized with the standardization of laparoscopic partial nephrectomy.

Aged↗

PubMedDate not supplied

Resection of anterior skull base tumors: comparison of combined traditional and endoscopic techniques.

BACKGROUND: Traditional craniofacial resection (tCFR) has been used successfully for resection of anterior skull base (ASB) tumors. Minimally invasive endoscopic resection (MIER) also has been used recently; this strategy facilitates superior visualization, avoids facial incisions, and preserves local structures. The goal of this study was to compare the outcome for these two approaches. METHODS: Retrospective chart analysis was conducted to identify patients undergoing resection of ASB tumors between January 1995 and January 2003. Demographic data, tumor characteristics, and the surgical approach used were determined. The mean operative time, estimated blood loss, hospital stay, and complications were analyzed. Recurrence and mortality rates were calculated. RESULTS: Nine patients were managed with the MIER approach, and 16 patients were treated with the traditional open approach. No significant difference was observed between groups on operative time, estimated blood loss, or hospital stay. Major complications were encountered in 2/9 (22%) and 7/16 (44%) patients in the MIER and tCFR groups, respectively. Recurrence was observed in 3/9 (33%) and 5/14 (36%) of the patients in the MIER and tCFR groups, respectively. Mortality rates in the MIER and tCFR groups were 0/9 (0%) and 4/15 (27%), respectively. CONCLUSION: In this preliminary study, MIER of ASB neoplasia did not differ significantly from tCFR in operative time, estimated blood loss, hospital stay, or complication rate. Survival and recurrence rates were similar also. This early experience suggests that MIER is a viable alternative for the surgical management of ASB lesions in appropriately selected patients.

Adult↗