Pubic bone injuries in primiparous women: magnetic resonance imaging in detection and differential diagnosis of structural injury.

OBJECTIVE: To evaluate the utility of magnetic resonance imaging (MRI) in diagnosing structural injury in primiparous women at risk for pelvic floor injury. METHODS: This was an observational study of 77 women who underwent 3T MRI after delivery. Women were operationally defined as high risk (n = 45) for levator ani muscle tears (risk factors: second-stage labor > 150 min or < 30 min, anal sphincter tear, forceps, maternal age > 35 years and birth weight > 4000 g) or low risk (n = 32): vaginally delivered without these risk factors (n = 12); delivered by Cesarean section after second-stage labor > 150 min (n = 14) or delivered by Cesarean section without labor (n = 6). All women were imaged using fluid-sensitive MRI sequences. Two musculoskeletal radiologists reviewed images for bone marrow edema, fracture, pubic symphysis measurements and levator ani tear. RESULTS: MRI showed pubic bone fractures in 38% of women at high risk for pelvic floor injury and in 13% of women at low risk for pelvic floor injury (χ(2) (3) = 9.27, P = 0.03). Levator ani muscle tears were present in 44% of the high-risk women and in 9% of the low-risk women (χ(2) (3) = 11.57, P = 0.010). Bone marrow edema in the pubic bones was present in 61% of women studied across delivery categories. Complex patterns of injury included combinations of bone marrow edema, fractures, levator ani tears and pubic symphysis injuries. No MRI-documented injuries were present in 18% of women at high risk and 44% at low risk for pelvic floor injury (χ(2) (1) = 6.2, P = 0.013). CONCLUSIONS: Criteria identifying primiparous women at risk for pelvic floor injury can predict increased risk of bone and soft tissue changes at the pubic symphysis. Fluid-sensitive MRI has utility for differential diagnosis of structural injury in postpartum women.

Women's Knowledge of Bladder Health: What We Have Learned in the Prevention of Lower Urinary Tract Symptoms (PLUS) Research Consortium.

Purpose of Review: The goal of this manuscript is to review the current literature on bladder health education, summarize Prevention of Lower Urinary Tract Symptoms (PLUS) [50] findings on environmental factors that influence knowledge and beliefs about toileting and bladder function, and describe how PLUS work will contribute to improved understanding of women's bladder-related knowledge and inform prevention intervention strategies. Recent Findings: Analysis of focus group transcripts revealed the various ways women view, experience, and describe bladder function. In the absence of formal bladder health educational platforms, women appear to develop knowledge of normal and abnormal bladder function from a variety of social processes including environmental cues and interpersonal sources. Importantly, focus group participants expressed frustration with the absence of structured bladder education to inform knowledge and practices. Summary: There is a lack of bladder health educational programming in the USA, and it is unknown to what degree women's knowledge, attitudes, and beliefs influence their risk of developing lower urinary tract symptoms (LUTS). The PLUS Consortium RISE FOR HEALTH study will estimate the prevalence of bladder health in adult women and assess risk and protective factors. A Knowledge, Attitudes, and Beliefs (KAB) questionnaire will be administered to determine KAB around bladder function, toileting, and bladder-related behaviors, and examine the relationship of KAB to bladder health and LUTS. The data generated from PLUS studies will identify opportunities for educational strategies to improve bladder health promotion and well-being across the life course.

Post-traumatic stress disorder, child abuse history, birthweight and gestational age: a prospective cohort study.

OBJECTIVE: To determine the extent to which prenatal post-traumatic stress disorder (PTSD) is associated with lower birthweight and shorter gestation, and to explore the effects of childhood maltreatment as the antecedent trauma exposure. DESIGN: Prospective three-cohort study. SETTING: Ann Arbor and Detroit, Michigan, United States. SAMPLE: In all, 839 diverse nulliparas in PTSD-positive (n = 255), trauma-exposed, resilient (n = 307) and non-exposed to trauma (n = 277) cohorts. METHODS: Standardised telephone interview before 28 weeks of gestation to ascertain trauma history, PTSD, depression, substance use, mental health treatment history and sociodemographics, with chart abstraction to obtain chronic condition history, antepartum complications and prenatal care data, as well as outcomes. MAIN OUTCOME MEASURES: Infant birthweight and gestational age per delivery record. RESULTS: Infants born to women with PTSD during pregnancy had a mean birthweight 283 g less than infants of trauma-exposed, resilient women and 221 g less than infants of non-exposed women (F(3,835) = 5.4, P = 0.001). PTSD was also associated with shorter gestation in multivariate models that took childhood abuse history into account. Stratified models indicated that PTSD subsequent to child abuse trauma exposure was most strongly associated with adverse outcomes. PTSD was a stronger predictor than African American race of shorter gestation and a nearly equal predictor of birthweight. Prenatal care was not associated with better outcomes among women abused in childhood. CONCLUSIONS: Abuse-related PTSD may be an additional or alternative explanation for adverse perinatal outcomes associated with low socio-economic status and African American race in the USA. Biological and interventions research is warranted along with replication studies in other nations.

The warfarin-sulfinpyrazone interaction: stereochemical considerations.

To allow the simultaneous evaluation of the interaction between sulfinpyrazone and each enantiomer of racemic warfarin, pseudoracemic warfarin (1:1 12C-R(+) and 13C-S(-)warfarin) was given to six normal subjects both before and during oral sulfinpyrazone dosing. Serial blood and urine samples were analyzed for unchanged warfarin and its metabolic products by GC/MS. A mass balance of an oral dose of pseudoracemic warfarin, containing a tracer quantity of 14C-warfarin, was carried out in one of the subjects by monitoring 14C levels in urine and feces for 15 days. Concomitant sulfinpyrazone dosing markedly increased hypoprothrombinemia, decreased clearance of (S)-warfarin, and increased clearance of (R)-warfarin. Sulfinpyrazone also decreased the urinary excretion of warfarin-related products but increased their fecal excretion by an equivalent amount. Virtually all of the administered warfarin dose could be accounted for either as unchanged drug or known metabolites. Pharmacokinetic analysis of the data suggests the following: At least four distinct enzymes (two oxidases and two reductases) are involved in the metabolism of warfarin. Sulfinpyrazone increases the hypoprothrombinemia caused by warfarin primarily by inhibition of the cytochrome P-450-mediated oxidation of (S)-warfarin, the biologically more potent enantiomer. The increased clearance of (R)-warfarin results not from induction, but from its selective displacement from plasma protein binding sites.

Acceleration of oxidative folding of bovine pancreatic ribonuclease A by anion-induced stabilization and formation of structured native-like intermediates.

Phosphate anions accelerate the oxidative folding of reduced bovine pancreatic ribonuclease A with dithiothreitol at several temperatures and ionic strengths. The addition of 400 mM phosphate at pH 8.1 increased the regeneration rate of native protein 2.5-fold at 15 degrees C, 3.5-fold at 25 degrees C, and 20-fold at 37 degrees C, compared to the rate in the absence of phosphate. In addition, the effects of other ions on the oxidative folding of RNase A were examined. Fluoride was found to accelerate the formation of native protein under the same oxidizing conditions. In contrast, cations of high charge density or ions with low charge density appear to have an opposite effect on the folding of RNase A. The catalysis of oxidative folding results largely from an anion-dependent stabilization and formation of tertiary structure in productive disulfide intermediates (des-species). Phosphate and fluoride also accelerate the initial equilibration of unstructured disulfide ensembles, presumably due to non-specific electrostatic and hydrogen bonding effects on the protein and solvent.

Pharmacokinetics and metabolism of benzene in Zymbal gland and other key target tissues after oral administration in rats.

Solid tumors have been reported in the Zymbal gland, oral and nasal cavities, and mammary gland of Sprague-Dawley rats following chronic oral administration of benzene. The cause for the specificity of such lesions remains unclear, but it is possible that tissue-specific metabolism or pharmacokinetics of benzene is responsible. Metabolism and pharmacokinetic studies were carried out in our laboratory with 14C-benzene at oral doses of 0.15 to 500 mg/kg to ascertain tissue retention, metabolite profile, and elimination kinetics in target and nontarget organs and in blood. Findings from those studies indicate the following: a) the Zymbal gland is not a sink or a site of accumulation for benzene or its metabolites even after a single high dose (500 mg/kg) or after repeated oral administration; b) the metabolite profile is quantitatively different in target tissues (e.g., Zymbal gland, nasal cavity), nontarget tissues and blood; and (c) pharmacokinetic studies show that the elimination of radioactivity from the Zymbal gland is biphasic.

Clinician-specific episiotomy rates: impact on perineal outcomes.

Recent, large, randomized, controlled trials of the effects of episiotomy on perineal damage have confirmed that episiotomy is associated with an increased risk of damage to the perineum. Yet episiotomy remains the most common surgical procedure women undergo. This article examines if clinician experience, rather than scientific evidence, forms the basis for continuing this practice. Perineal outcome data are analyzed for 865 low-risk women who were attended at birth by the staff nurse-midwives or faculty obstetricians at a university-based, tertiary-care hospital. Data were collected under routine, nonexperimental conditions such that the circumstances of the labor and the clinician's preferences were allowed to determine management decisions regarding the use of episiotomy or other techniques of perineal management. Multivariate findings indicate that in the absence of episiotomy, rates of perineal integrity were highest among clinicians who usually had the lowest rate of episiotomy use. When an episiotomy was done, rates of third- and fourth-degree extensions were highest among clinicians who used episiotomy most frequently. This finding challenges the idea that clinicians who were very experienced with the use of episiotomy would avoid complications such as extensions. Future research should explore the use of nonsurgical techniques such as those employed by midwives to promote perineal integrity. Then interdisciplinary research and evidence-based education regarding these techniques can occur to improve perineal outcomes for all women.

A substance use prevention framework: considering the social context for African American girls.

Shifting patterns of substance use (that is, early initiation, increased marijuana use, narrowing differences in gender use) and the disproportionate socioeconomic obstacles that are related to substance use among ethnically diverse adolescent females create the need to develop ethnic and gender-specific substance use prevention frameworks. This article describes and applies a substance use prevention framework to African American females. Gender socialization and self-efficacy are presented as key concepts, along with the assertion that every substance use prevention framework should examine the influences of specific societal factors (such as racism, sexism, classism, and ageism) on substance use. Rationale and guidelines for designing ethnically sensitive and gender-specific research projects and intervention programs regarding substance use prevention are offered. Public health nurses (PHNs) are uniquely positioned to use this framework in their work with African American adolescent girls, specifically, and in general with other ethnically diverse groups.

Health effects of the alkylbenzenes. I. Toluene.

The alkylbenzenes, toluene being the most common example, represent a class of six-membered ring aromatic compounds that have a variety of alkyl groups attached. These chemicals are liquids with relatively low boiling points and are used primarily as solvents or as starting materials in the synthesis of other chemicals and drugs. They are also integral components of gasoline, distillate fuels and other petroleum products. These substituted aromatics are economically important in the chemical, petroleum, pharmaceutical, polymer, paint and dye industries. Alkylbenzenes such as toluene, xylene, ethylbenzene, styrene and cumene are toxicologically important since they are produced, used or disposed of in the largest quantities and therefore might pose significant and potential health risks to man and the environment. In general, the toxicity of alkylbenzenes has been found to be relatively low. Also, for the most part, human and environmental risks are low; however, there may be a few operations where the potential for high exposure could exist. These exposures are minimized by workplace controls or personal protective equipment. Furthermore, health risks for humans are minimized by guidelines for maximum allowable exposure concentrations which have been established for the workplace. This present paper reviews the toxicology and disposition of toluene in animals and humans.

A sensitive and specific stable isotope assay for warfarin and its metabolites.

A capillary gas chromatographic mass spectrometric method for the quantification of warfarin and its known metabolites from microsomal incubations is described. Deuterium labelled 4', 6-, 7- and 8-hydroxy warfarins are used as internal standards and the method has detection limits of 1 ng ml-1 with 20 ng ml-1 being the lower limit for accurate quantification.

Health effects of the alkylbenzenes. II. Xylenes.

The alkylbenzenes are a class of six-membered ring aromatic compounds that have a variety of alkyl groups attached. These chemicals are liquids with relatively low boiling points used primarily as solvents or as starting materials in the synthesis of other chemicals and drugs. They are integral components of gasoline, distillate fuels and other petroleum products and are economically important in the chemical, petroleum, pharmaceutical, polymer, paint and dye industries. Alkylbenzenes such as toluene, the xylenes, ethylbenzene, styrene and cumene are produced and utilized in large quantities and therefore, present the possibility of exposure to humans and to wildlife. Fortunately, the toxicity of alkylbenzenes has been found to be rather low and therefore, the human and environmental risks are probably low. In modern industrial activities, exposures to the alkylbenzenes are minimized by workplace controls or personal protective equipment which meet guidelines for maximum allowable exposure concentrations that have been established for the workplace. Nevertheless, considerable quantities of alkylbenzenes are released to the environment each year through solvent and fuel evaporation, accidental spills and misuse, and considerable toxicological information for these materials has appeared in the recent literature. This present paper, the second in a series reviewing the potential health effects of alkylbenzenes, covers the toxicology and disposition of the dimethyl-substituted benzenes (the xylenes) in animals and man.

Correlation of systemic and developmental toxicities with chemical component classes of refinery streams.

Refinery streams are complex mixtures, but of a relatively few homologous series of hydrocarbons (paraffins, olefins, naphthenics, and aromatics). Studies were performed to determine if systemic and developmental toxicity were related to the presence and levels of certain classes of refinery stream components. We have performed systemic toxicology studies in the rat on 13 refinery streams: Clarified Slurry Oil, Coker Light Gas Oil, Distillate Aromatic Extract, Heavy Atmospheric Gas Oil, Heavy Coker Gas Oil (from three refineries), Heavy Vacuum Gas Oil, Light Catalytically Cracked Naphtha, Light Cycle Oil, Syntower Bottoms, Vacuum Tower Overhead, and Visbreaker Gas Oil. Rats were exposed via repeated dermal administration (daily) at several dose levels. Developmental toxicology studies were performed on these same streams with the following exceptions: only two Heavy Coker Gas Oils were tested and Visbreaker Gas Oil was not tested. End points for systemic toxicity (13-week) studies included skin irritation, body and organ weights, hematology, and serum chemistry; for developmental toxicity studies some of these same end points (excluding hematology) were considered, but they also included resorption and fetal body weight. In general, toxicity was correlated with concentrations of polycyclic aromatic compounds (PAC) composed of 3, 4, 5, 6, and/or 7 rings (decreased thymus weight, increased liver weight, aberrant hematology and serum chemistry, increased incidence of resorption, decreased fetal body weight), PAC containing nonbasic nitrogen heteroatoms (increased mortality, decreased body weight, decreased thymus weight, increased liver weight, decreased hemoglobin content and hematocrit level, decreased fetal body weight), and/or PAC containing sulfur heteroatoms (decreased red blood cell and platelet counts, increased sorbitol dehydrogenase.)(ABSTRACT TRUNCATED AT 250 WORDS)

Fundal height measurement. Part 3--The effect of maternal position on fundal height measurements.

The effect of maternal position on fundal height measurements was studied in 192 nonobese women between 21 and 36 weeks of gestation. Four clinicians participated in the study and each clinician obtained measurements on 48 women. Fundal height measurements were obtained in each of four positions: supine; trunk elevation; knee flexion; and trunk elevation with knee flexion. The sequence in which measurements were obtained was assigned randomly. Clinicians were blinded to the results of their measurements. Measurements obtained in the supine position were largest, and measurements obtained in the trunk elevation with knee flexion position were smallest. Repeated measures analysis of variance demonstrated that measurements obtained in the four positions were significantly different (F = 87.71, df = 3,573, P < .001). A posteriori comparisons demonstrated that measurements obtained in each position were significantly different except for measurements obtained in the trunk elevation and knee flexion positions. These findings indicate that clinicians should be consistent when they position patients to obtain fundal height measurements.

Systemic toxicity from subchronic dermal exposure, chemical characterization, and dermal penetration of catalytically cracked clarified slurry oil.

Clarified slurry oil (CSO), the heavy residual fraction from the fluidized catalytic cracker, was applied to the shaven backs of groups of 10 male and 10 female Sprague-Dawley rats 5 days/week for 13 weeks at doses of 8, 30, 125, or 500 mg/kg/day, and to another group for 2 weeks at doses of 2000 mg/kg/day. The rats were fitted with cardboard Elizabethan collars to minimize the ingestion of the test material, which was applied undiluted and remained uncovered on the skin. A similar group of rats served as controls; they were treated in the same manner except that no CSO was applied to their skin. There was a dose-related mortality and depression of body weight gain in the rats treated with CSO at doses of 30 mg/kg/day or greater; none of the rats dosed at 2000 mg/kg/day survived more than 2 weeks. The primary target organs of CSO toxicity were the liver, thymus, and bone marrow. The effects on the liver included increased weight (250% at 500 mg/kg/day), cholangiolitis, diffuse liver cell degeneration and hypertrophy, necrosis, fibrosis, decreased serum glucose, increased levels of alkaline phosphatase, aspartate aminotransferase, alanine amino transferase, bilirubin, and triglycerides. The thymus was found to be small and upon microscopic examination to be atrophic or hypoplastic. Erythroid hypoplasia was found in the bone marrow of some of the rats dosed at 30 mg/kg/day and increased in severity with increasing dose. The erythroid hypoplasia was accompanied by a dose-related anemia. Even in the rats dosed at 8 mg/kg/day, very slight abnormalities in the bile ducts were observed upon microscopic examination of the liver. Chromatographic separation and analyses demonstrated that CSO contains about 58% 3- to 5-ring polycyclic aromatic hydrocarbons (PAHs) and approximately 8-10% carbazole derivatives. In vitro and in vivo skin penetration studies demonstrated that the carbazole materials penetrate through the skin to a considerable extent (about 44%); less penetration was observed with 2- or 3-ring (8-13%) or 5-ring PAHs (3%).