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Biomedical subjects

B A Mueller

Publications and source records attributed to B A Mueller.

At least 19 recordsLinked to original sources

Beauty product-related exposures and childhood brain tumors in seven countries: results from the SEARCH International Brain Tumor Study.

Data from 1218 cases of childhood brain tumors (CBT) diagnosed between 1976 and 1994 and 2223 matched controls from the general population were included in an analysis of maternal beauty product exposure and beauty-related employment in 9 centers in 7 countries. A 50% increased odds ratio (OR) [95% confidence interval (CI) = 1.0-2.1] for CBT was observed among children of mothers who were exposed via personal use of and/or possible ambient contact with beauty products during the 5 years preceding the index child's birth compared with children of mothers never exposed to beauty products during this time period. Overall maternal personal use of hair-coloring agents in the month before or during the pregnancy of the index child's birth was not associated with CBT (OR = 1.0, CI = 0.83-1.3) or with astroglial (OR = 1.1, CI = 0.85-1.4), PNET (OR = 1.0, CI = 0.71-1.5) and other glial subtypes (OR = 1.0, CI = 0.62-1.0). Similarly, no statistically increased ORs or discernable pattern of risk estimates were observed for period of use or for number of applications per year for maternal personal use of hair-coloring agents overall or by histologic type. Among children born on or after 1980, increased ORs for CBT were associated with maternal non-work-related exposure to any beauty products (OR = 2.6, CI = 1.2-5.9), hair-dyes (OR = 11, CI = 1.2-90), and hair sprays (OR = 3.4, CI = 1.0-11). No overall increased OR for CBT was observed among children of mothers employed in beauty-related jobs during the 5 years preceding the index child's birth compared with those who reported no beauty-related employment. In general, other specific beauty product-related exposures were not associated with increased ORs for CBT. Data from our study provide little evidence of an increased risk for CBT with mothers' exposures to beauty products.

Adolescent↗

Parental exposure to polycyclic aromatic hydrocarbons and the risk of childhood brain tumors: The SEARCH International Childhood Brain Tumor Study.

Experimental evidence suggests that parental exposure to polycyclic aromatic hydrocarbons (PAH), which occurs primarily through tobacco smoke, occupational exposure, and air pollution, could increase the risk of cancer during childhood. Population-based case-control studies carried out in seven countries as part of the SEARCH Program compared data for 1,218 cases of childhood brain tumors and 2,223 controls (1976-1994). Parental occupational exposure to PAH during the 5-year period before birth was estimated with a job exposure matrix. Risk estimates were adjusted for child's age, sex, and study center. Paternal preconceptional occupational exposure to PAH was associated with increased risks of all childhood brain tumors (odds ratio (OR) = 1.3, 95% confidence interval: 1.1, 1.6) and astroglial tumors (OR = 1.4, 95% confidence interval: 1.1, 1.7). However, there was no trend of increasing risk with predicted level of exposure. Paternal smoking alone (OR = 1.4) was also associated with the risk of astroglial tumors in comparison with nonsmoking, non-occupationally-exposed fathers. Risks for paternal occupational exposure were higher, with (OR = 1.6) or without (OR = 1.7) smoking. Maternal occupational exposure to PAH before conception or during pregnancy was rare, and this exposure was not associated with any type of childhood brain tumor. This large study supports the hypothesis that paternal preconceptional exposure to PAH increases the risk of brain tumors in humans.

Adolescent↗

J/psi polarization in 800-GeV p-Cu interactions.

We present measurements of the polarization of the J/psi produced in 800-GeV proton interactions with a copper target. Polarization of the J/psi is sensitive to the ccmacr; production and hadronization processes. A longitudinal polarization is observed at large x(F), while at small x(F) the state is produced essentially unpolarized or slightly transversely polarized. No significant variation of the polarization is observed versus p(T).

Journal Article↗

The relationship of placenta previa and history of induced abortion.

OBJECTIVES: We evaluated the risk of placenta previa being associated with a history of induced abortion by different surgical procedures. METHODS: Cases (n=192) were women who had a singleton delivery complicated by placenta previa at a major obstetric care hospital in western Washington state between April 1, 1990 and December 31, 1992. Controls (n=622) were women with singleton deliveries not complicated by placenta previa or abruption. Odds ratios, determined by logistic regression, approximate the relative risks. RESULTS: Vacuum aspiration abortion was not associated with an increased risk of placenta previa (OR 0.9, 95% CI 0.6-1.5). However, the risk of placenta previa increased with the number of sharp curettage abortions (OR 2.9, 95% CI 1.0-8.5 for > or =3). CONCLUSIONS: Risk of placenta previa may be increased in a dose response fashion by multiple sharp curettage abortions. However, vacuum aspiration does not confer an increased risk, and may be a better alternative.

Abortion, Induced↗

Measurement of the high energy two-body deuteron photodisintegration differential cross section.

The first measurements of the d(gamma,p)n differential cross section at forward angles and photon energies above 4 GeV were performed at the Thomas Jefferson National Accelerator Facility (JLab). The results indicate evidence of an angular dependent scaling threshold. Results at straight theta(cm) = 37 degrees are consistent with the constituent counting rules for E(gamma) greater, similar 4 GeV, while those at 70 degrees are consistent with the constituent counting rules for E(gamma) greater, similar 1.5 GeV.

Journal Article↗

Observation of polarization in bottomonium production at square root of s = 38.8 GeV.

We present a measurement of the polarization observed for bottomonium states produced in p-Cu collisions at square root of s = 38.8 GeV. The angular distribution of the decay dimuons of the Upsilon(1S) state shows no polarization at small values of the fractional longitudinal momentum x(F) and transverse momentum p(T) but significant positive transverse production polarization for either p(T)>1.8 GeV/c or for x(F)>0.35. The Upsilon(2S+3S) (unresolved) states show a large transverse production polarization at all values of x(F) and p(T) measured. These observations challenge NRQCD calculations of the polarization expected in the hadronic production of bottomonium states.

Journal Article↗

Do protective factors reduce the risk of hospitalization in infants of teenaged mothers?

OBJECTIVE: To determine the risk of hospitalization associated with prenatal care use and indicators of socioeconomic status and social support among infants of teenage mothers. DESIGN: Population-based case-control study. SETTING: Nonfederal hospitals in Washington State. PARTICIPANTS: Infants born from 1987 to 1995 to mothers younger than 20 years were identified using linked birth certificate-state hospital discharge data. Cases consisted of 8052 infants who were hospitalized during the first year of life at least 2 days after birth hospitalization discharge. An equal number of controls, frequency matched on birth year and maternal age group, were randomly sampled from among nonhospitalized infants. MAIN OUTCOME MEASURE: Hospitalization in the first year of life. RESULTS: Infants with a father listed on the birth certificate or whose mothers had commercial health insurance had a decreased risk of hospitalization (adjusted odds ratios, 0.91 and 0.78, respectively; 95% confidence intervals, 0.83-0.99 and 0.71-0.85, respectively). Participation in state-funded pregnancy programs, adequacy of prenatal care, or marital status did not affect the risk of hospitalization, except among infants whose mothers received more than adequate prenatal care (adjusted odds ratio, 1.15; 95% confidence interval, 1.03-1.29). CONCLUSION: Our results suggest that teenaged mothers who list a father on the birth certificate or who have insurance, indicative of higher socioeconomic status, may have a reduced risk of hospitalization for their infants. Teenaged mothers who receive more than adequate prenatal care may have pregnancy complications that place their infants at increased risk of hospitalization. The effect of these protective factors should be clarified in future studies.

Adolescent↗

Biomechanical factors and failure of transcervical hip fracture repair.

OBJECTIVE: To assess the association between biomechanical measurements (bone quality of the femoral neck, comminution, fracture angle, and fracture level) and the likelihood of fixation failure among patients who have a multiple screw stabilisation of an intracapsular hip fracture. METHODS: A cohort study of 139 Washington State residents greater than 60 years of age who sustained a fall-related transcervical hip fracture treated from 1990 to 1996 inclusive. Measurements of bone quality, fracture angle, fracture level, and comminution were taken from perioperative X-rays. The outcome measure was clinical failure of the internal fixation procedure within 12 months of hospital discharge, as measured by readmission for further surgery to that hip. RESULTS: Of the four biomechanical aspects examined, only bone quality, as measured by presence of an ICD code for osteoporosis, was significantly associated with risk of subsequent hospitalisation for revision surgery (adjusted hazard ratio 7.7, 95% CI 1.8-32.8). CONCLUSION: A diagnosis code for osteoporosis was related to the outcome of intracapsular fractures repaired with multiple pins. Other biomechanical measurements from diagnostic X-rays were not related to the need for further surgery.

Aged↗

Cefazolin dialytic clearance by high-efficiency and high-flux hemodialyzers.

Cefazolin dialytic clearance has not been determined in patients undergoing hemodialysis with high-efficiency or high-flux dialyzers. The objective of this study is to determine the pharmacokinetics and dialytic clearance of cefazolin and develop dosing strategies in these patients. Twenty-five uninfected subjects undergoing chronic thrice-weekly hemodialysis were administered a single dose of intravenous cefazolin (15 mg/kg) after their standard hemodialysis session. Fifteen subjects underwent hemodialysis with high-efficiency hemodialyzers, and 10 subjects underwent hemodialysis with high-flux hemodialyzers. Blood and urine samples were collected serially over the interdialytic period, during the next intradialytic period, and immediately after the next hemodialysis session. Serum and urine concentrations of cefazolin were determined by high-performance liquid chromatography. Differential equations describing a two-compartment model were fit to the cefazolin serum concentration-time data over the study period, and pharmacokinetic parameters were determined. Mean dialytic clearance values for cefazolin were significantly greater in the high-flux group compared with the high-efficiency group (30.9 +/- 6.52 versus 18.0 +/- 6.26 mL/min, respectively; P: < 0.05). Cefazolin reduction ratios were significantly greater (0.62 +/- 0.08 versus 0.50 +/- 0.07; P: < 0.005) in the high-flux group compared with the high-efficiency group and correlated well with equilibrated urea reduction. The pharmacokinetic model developed from patient data was used to simulate cefazolin serum concentration data for high-efficiency and high-flux dialyzers. Cefazolin doses of 15 or 20 mg/kg after each hemodialysis session maintained adequate serum concentrations throughout a 2- or 3-day interdialytic period regardless of hemodialyzer type.

Adult↗

Residential water source and the risk of childhood brain tumors.

Gestation may represent a window of susceptibility to transplacental effects of environmental exposures, including chemicals in water. The N-nitroso compounds (NNC), a class of chemicals with demonstrated neurocarcinogenic potential, include substances detected in drinking water. We used data from a study of possible risk factors for childhood brain tumors (CBT) to investigate the association of source of residential drinking water during pregnancy and CBT occurrence among offspring. In addition, dipstick measurements were made of nitrates and nitrites in tap water for the subset of women living in the same home they had lived in during their pregnancies. Population-based CBT cases (n = 540) and controls (n = 801) were identified in three regions including Los Angeles County, and the San Francisco Bay Area of California, and the Seattle-Puget Sound area of western Washington state. Overall, we observed no increased risk of CBT in offspring associated with wells as the source of residential water. However, an increased risk of CBT [odds ratio (OR) = 2.6; 95% confidence interval (CI), = 1.3-5.2] was observed in western Washington among offspring of women who relied exclusively on well water, and a decreased risk of CBT (OR = 0.2; 95% CI, 0.1-0.8) was observed in Los Angeles County. Among the small subset of subjects for whom dipstick measurements of tap water were available, the risk of CBT associated with the presence of either measurable nitrite and/or nitrate was 1.1 (95% CI, 0.7-2.0). Given the crude measurement method employed and because measurements often were obtained years after these pregnancies occurred, the relevance of the dipstick findings is unclear. The lack of consistency in our findings related to residential water source does not support the hypothesis of increased risk related to consumption of well water; however, regional differences in well water content may exist, and the increased risk observed in western Washington deserves further evaluation.

Adolescent↗

Noni juice (Morinda citrifolia): hidden potential for hyperkalemia?

We report the case of a man with chronic renal insufficiency who self-medicated with an alternative medicine product known as noni juice (Morinda citrifolia). The patient presented to the clinic with hyperkalemia despite claiming adherence to a low-potassium diet. The potassium concentration in noni juice samples was determined and found to be 56.3 mEq/L, similar to that in orange juice and tomato juice. Herbal remedies and alternative medicine products may be surreptitious sources of potassium in patients with renal disease.

Beverages↗

Reliability of demographic, smoking and occupational data provided by mothers vs. fathers in a childhood cancer study.

A large case-control study of children was used to test mothers' reporting of information on fathers' background, lifestyle and occupational factors. For a subset (104) of 1341 enrolled families, both parents were interviewed about fathers' characteristics. Reliability of reporting was determined for fathers' race, education, smoking status, non-recent job history and use of occupational agents. The ability of mothers to report fathers' race, education and smoking status was high (kappa > 0.70). Mothers were generally able to report jobs held by the fathers in the 5 years preceding the birth of the child, but reliability was higher for jobs held for longer (kappa typically above 0.70), rather than shorter periods (kappa above 0.40). The finding that mothers' reporting on fathers' background, lifestyle and non-recent job history was reliable is encouraging, because many studies on childhood health rely exclusively on information from interviews with mothers. However, mothers were not reliably able to describe exposure to specific occupational agents.

California↗

A preschool program for safety and injury prevention delivered by home visitors.

OBJECTIVE: To evaluate the feasibility, acceptability, and effectiveness of an injury prevention program delivered by school based home visitors to the families of low income children attending preschool enrichment programs in Washington State. STUDY SAMPLE: The families of children attending preschool Head Start programs in two regions were eligible. A total of 213 families (77.8% of those eligible) from intervention sites, and 149 families (71.9% of those eligible) from concurrent comparison sites, agreed to participate and completed the trial. INTERVENTION: Trained school personnel conducted home safety inspections as part of a planned home visit. Intervention families were offered educational materials as well as smoke detectors, batteries, ipecac, and age appropriate car safety restraints based on results of the home inspection. EVALUATION METHODS: At a repeat home visit three months later, the proportion of families with a positive change in injury prevention knowledge or behavior among those in the intervention group was compared with the proportion in the comparison group. Smoke detector presence and function were observed. RESULTS: Among families without a working smoke detector at baseline, the intervention was associated with an increased probability of having a working detector at follow up (relative risk (RR) 3.3, 95% confidence interval (CI) 1.3 to 8.6). Intervention families were also more likely to report the presence of ipecac in the home (RR 4.7, 95% CI 3.0 to 7.3) at follow up and to have obtained an age appropriate booster seat (RR 4.1, 95% CI 1.9 to 8.8). The program was acceptable to client families and to the home visitors who conducted the intervention. CONCLUSIONS: Among the families of low income children enrolled in preschool enrichment programs, home safety inspections and the distribution of safety supplies by school based home visitors appears to improve knowledge and behavior related to poisoning, smoke detector installation, and car safety seat use over three months of follow up.

Accidents, Home↗

Vancomycin assay performance in patients with end-stage renal disease receiving hemodialysis.

STUDY OBJECTIVE: To compare the performance of polyclonal fluorescence polarization immunoassay (pFPIA) with that of enzyme-multiplied immunoassay technique (EMIT) in patients receiving vancomycin and hemodialysis. SETTING: Outpatient hemodialysis center. PATIENTS: Seven subjects with end-stage renal disease treated with hemodialysis 3 times/week with a cellulose triacetate hemodialyzer. INTERVENTION: Subjects received vancomycin 1000 mg intradialytically during the first study session and 750 mg every other hemodialysis session thereafter for 4 weeks. MEASUREMENTS AND MAIN RESULTS: Blood samples were obtained throughout the study, and vancomycin serum concentrations were determined by pFPIA and EMIT. The mean +/- SD difference (estimate of bias) between assays was -1.10 +/- 1.35 mg/L. The limits of agreement (mean difference +/- 1.96 x SD) between them were -3.80-1.60 mg/L. CONCLUSION: Our data suggest that the manufacturer's changes in the vancomycin pFPIA eliminated overestimation of drug concentrations in patients undergoing high-permeability hemodialysis.

Anti-Bacterial Agents↗

Pregnancy after breast carcinoma: outcomes and influence on mortality.

BACKGROUND: To the authors' knowledge, no previous studies have identified an adverse effect of pregnancy on patient survival after breast carcinoma. However, results are difficult to interpret because of failure to control for stage of disease at the time the pregnancy occurred. METHODS: Study participants were women diagnosed with invasive breast carcinoma between 1983-1992 who previously had participated in a population-based case-control study or, if deceased, proxy respondents. Information regarding subsequent pregnancies was obtained by self-administered questionnaire or telephone interview. Information regarding breast carcinoma recurrences was obtained by questionnaire and from cancer registry abstracts. Women who became pregnant after a diagnosis of breast carcinoma (n = 53) were matched with women without subsequent pregnancies based on stage of disease at diagnosis and a recurrence free survival time in the comparison women greater than or equal to the interval between breast carcinoma diagnosis and onset of pregnancy in the women with a subsequent pregnancy. RESULTS: Sixty-eight percent of women who became pregnant after being diagnosed with breast carcinoma delivered one or more live-born infants. Miscarriages occurred in 24% of the patients who became pregnant compared with 18% of the controls (women without breast carcinoma) of similar ages from the case-control study. Five of the 53 women who had been pregnant after breast carcinoma died of the disease. The age-adjusted relative risk (RR) of death associated with any subsequent pregnancy was 0.8 (95% confidence interval [95% CI], 0.3-2.3). All five deaths occurred among the 36 women who had a live birth (age-adjusted RR = 1.1; 95% CI, 0.4-3.7). CONCLUSIONS: The findings of the current study are based on a small number of deaths but do not suggest that pregnancy after a diagnosis of breast carcinoma has an adverse effect on survival.

Adult↗