Hydrogen peroxide-induced apoptosis is CD95-independent, requires the release of mitochondria-derived reactive oxygen species and the activation of NF-kappaB

Reactive oxygen species (ROS) play an important role in cell death induced by many different stimuli. This study shows that hydrogen peroxide-induced apoptosis in T-cells did not require tyrosine kinase p561ck, phosphatase CD45, the CD95 receptor and its associated Caspase-8. H2O2-triggered cell death led to the induced cleavage and activation of Caspase-3. Hydrogen peroxide-treatment of T-cells resulted in the formation of mitochondrial permeability transition pores, a rapid decrease of the mitochondrial transmembrane potential delta psi(m) and the release of Cytochrome C. Inhibition of the mitochondrial permeability transition by bongkrekic acid (BA), or interference with the mitochondrial electron transport system by rotenone or menadione prevented the cytotoxic effect of H2O2. Antimycin A, a mitochondrial inhibitor that increases the release of mitochondrial ROS (MiROS), enhanced apoptosis. Overexpression of Bcl-2 and the viral anti-apoptotic proteins BHRF-1 and E1B 19K counteracted H2O2-induced apoptosis. Pharmacological and genetic inhibition of transcription factor NF-kappaB protected cells from hydrogen peroxide-elicited cell death. This detrimental effect of NF-kappaB mediating hydrogen peroxide-induced cell death presumably relies on the induced expression of death effector genes such as p53, which was NF-kappaB-dependently upregulated in the presence of H2O2.

Prevention of nosocomial pneumonia in intubated patients: respective role of mechanical subglottic secretions drainage and stress ulcer prophylaxis

Chronic microaspiration through a tracheal cuff is the main culprit in the penetration and colonization of the lower respiratory tract. A total of 145 patients intubated for more than 3 days were randomly assigned to a double nosocomial pneumonia (NP) prevention: 1--Prevention of aspiration by hourly subglottic secretion drainage (SSD) with a specific endotracheal tube (HI-LO Evac tube, Mallinckrodt); 2--Prevention of gastric colonization using either sucralfate or antacids. Four random groups were defined, similar in age and severity of illness. Subglottic secretion drainage treatment was associated with: a) a twice lower incidence of NP (no-SSD: 29.1%, SSD: 13%); b) a prolonged time of onset of NP (no-SSD: 8.3 +/- 5 days, SSD: 16.2 +/- 11 days); c) a decrease in the colonization rate from admission to end-point day in tracheal aspirates (no-SSD: +21.3%, SSD: +6.6%) and in subglottic secretions (no-SSD: +33.4%, SSD: +2.1%). Sucralfate was not associated with a significantly lower incidence of NP (antacids: 23.6%, sucralfate: 17.8%), but with a lower increase in the colonization rate in subglottic and gastric aspirates, from admission to end-point day.

Caesarean section rate for maternal indication in sub-Saharan Africa: a systematic review

INTRODUCTION

Rates of caesarean sections in more-developed countries have been rising since 1970, and vary greatly between less-developed countries. Present estimates, based on data from more-developed countries need to be validated with data from less-developed countries. We estimated the need for caesarean section for maternal indication in a population of pregnant women in west Africa (MOMA survey).

METHODS

The expected caesarean section rate was calculated from the rate of obstetric risk in the MOMA population, and rates of caesarean section in published work.

FINDINGS

Three-quarters of women from hospitals of sub-Saharan Africa were delivered by caesarean section for maternal reasons. Such intervention was needed for six main reasons, protracted labour, abruptio placentae, previous caesarean section, eclampsia, placenta praevia, and malpresentation. Although the observed rate of caesarean section in west African women is 1.3%, our results, combined with those of published work suggest a range of 3.6-6.5% (median, 5.4%).

INTERPRETATION

Our method might not be strictly accurate, but it is simple and provides informative findings that can help policy makers and health planners in sub-Saharan Africa to design and follow up programmes to reach the optimum caesarean section rate. Moreover, application of this method to hospital data could improve practitioners' assessments in these countries.

Maternal mortality and access to obstetric services in West Africa

OBJECTIVES

Process evaluation has become the mainstay of safe motherhood evaluation in developing countries, yet the extent to which indicators measuring access to obstetric services at the population level reflect levels of maternal mortality is uncertain. In this study we examine the association between population indicators of access to obstetric care and levels of maternal mortality in urban and rural West Africa.

METHODS

In this ecological study we used data on maternal mortality and access to obstetric services from two population-based studies conducted in 16 sites in eight West African countries: the Maternal Mortality and Obstetric Care in West Africa (MAMOCWA) study in rural Sénégal, Guinea-Bissau and The Gambia and the Morbidité Maternelle en Afrique de l'Ouest (MOMA) study in urban Burkina Faso, Côte d'Ivoire, Mali, Mauritanie, Niger and Sénégal.

RESULTS

In rural areas, maternal mortality, excluding early pregnancy deaths, was 601 per 100,000 live births, compared with 241 per 100,000 for urban areas [RR = 2.49 (CI 1.77-3.59)]. In urban areas, the vast majority of births took place in a health facility (83%) or with a skilled provider (69%), while 80% of the rural women gave birth at home without any skilled care. There was a relatively close link between levels of maternal mortality and the percentage of births with a skilled attendant (r = -0.65), in hospital (r = -0.54) or with a Caesarean section (r = -0.59), with marked clustering in urban and rural areas. Within urban or rural areas, none of the process indicators were associated with maternal mortality.

CONCLUSION

Despite the limitations of this ecological study, there can be little doubt that the huge rural-urban differences in maternal mortality are due, at least in part, to differential access to high quality maternity care. Whether any of the indicators examined here will by themselves be good enough as a proxy for maternal mortality is doubtful however, as more than half of the variation in mortality remained unexplained by any one of them.

Prospective study of nosocomial colonization and infection due to Pseudomonas aeruginosa in mechanically ventilated patients

OBJECTIVE

To investigate the respective contribution of endogenous and exogenous transmission of Pseudomonas aeruginosa in the colonization of lungs in the mechanically ventilated patient, to estimate the role of P. aeruginosa colonization in the occurrence of severe infections, and to extrapolate appropriate control measures for the prevention of P. aeruginosa ventilator-associated pneumonia.

DESIGN

Prospective study of the presence of P. aeruginosa (in stomach fluid, throat specimens, stool, and sputum) on admission, twice a week throughout the patient's stay, and in their environment. O-serotyping, pulsed-field gel electrophoresis, and arbitrarily-primed polymerase chain reaction were used to characterize the strains.

SETTING

The two intensive care units (ICUs 1 and 2) of a university hospital.

PATIENTS

During a 6-month period, 59 patients were included (21 in ICU 1 and 38 in ICU 2).

RESULTS

P. aeruginosa was isolated in 26 patients, including ten pneumonia cases and seven colonizations on admission. The incidence of acquired colonization was statistically different between the two ICUs: 5.5 and 20.5 per 1000 days of mechanical ventilation, in ICUs 1 and 2, respectively. Endogenous acquisition was the main origin of P. aeruginosa colonization (21 of 26 patients) and the upper respiratory tract was the main bacterial reservoir in broncho-pulmonary colonization and infection. However, during the 6-month period of the study, a multidrug-resistant strain of P. aeruginosa O:11, isolated in the sink of the room of 12 patients, was found responsible for two colonizations (1 digestive, 1 throat/lungs) and one pneumonia. As a whole, from 26 cases of colonization/infection with P. aeruginosa, 5 were related to an exogenous contamination (environmental reservoir in 4 patients and cross-contamination in one patient).

CONCLUSIONS

These results emphasize the need for applying various infection control measures to prevent colonization of patients with P. aeruginosa, including strategies to limit the potential of sinks from acting as a source or reservoir for this bacterium.

Co-stimulatory effect of nitric oxide on endothelial NF-kappaB implies a physiological self-amplifying mechanism

Here we investigated the effects of the second messenger molecule NO at various concentrations on the activation of transcription factor NF-kappaB, IkappaB-alpha kinase (IKK-alpha), Jun N-terminal kinase (JNK) and apoptosis in murine endothelial cells. Low concentrations of NO alone failed to activate NF-kappaB, IKK-alpha and JNK. When NF-kappaB was prestimulated by TNF-alpha or phorbol 12-myristate 13-acetate, the addition of NO at low concentrations enhanced the activation of NF-kappaB. This provides a mechanism for a self-amplifying signal in the inflammatory response, since the inducible NO synthase in endothelial cells is regulated by NF-kappaB. The co-stimulatory effect of NO on NF-kappaB activation was also evident from IKK-alpha kinase assays and reporter gene experiments in endothelial cells. High doses of NO impaired the TNF-alpha-induced DNA-binding activity of NF-kappaB. Accordingly, these high amounts of NO also repressed the TNF-alpha-induced transactivation by NF-kappaB as efficient as dexamethasone. The doses of NO required for the inhibition of NF-kappaB are not cytotoxic for the endothelial cells, enabling the establishment of an autoregulatory loop for NF-kappaB signaling.

A global reference for caesarean section rates (C-Model): a multicountry cross-sectional study

Objective

To generate a global reference for caesarean section (CS) rates at health facilities.

Design

Cross‐sectional study.

Setting

Health facilities from 43 countries.

Population/Sample

Thirty eight thousand three hundred and twenty‐four women giving birth from 22 countries for model building and 10 045 875 women giving birth from 43 countries for model testing.

Methods

We hypothesised that mathematical models could determine the relationship between clinical‐obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three‐step approach to generate the global benchmark of CS rates at health facilities: creation of a multi‐country reference population, building mathematical models, and testing these models.

Main outcome measures

Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate.

Results

According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C‐Model, with summary estimates ranging from 0.832 to 0.844. The C‐Model was able to generate expected CS rates adjusted for the case‐mix of the obstetric population. We have also prepared an e‐calculator to facilitate use of C‐Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/).

Conclusions

This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C‐Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS.

Tweetable abstract

The C‐Model provides a customized benchmark for caesarean section rates in health facilities and systems.

The C‐Model provides a customized benchmark for caesarean section rates in health facilities and systems.

Short- and long-term prognosis, functional outcome following ICU for elderly

Among 1532 ICU patients we analysed 295 elderly patients (19%) aged more than 70-years-old. We determined prospectively the immediate and subsequent one-year outcome with a study of the predictive value of their ICU admission parameters. Then we followed the ICU survivors over the year after discharge (1, 6, 12 months) by quality of life questionnaires. ICU mortality was 26.7%; SAPS was the only predictor of short term mortality. On ICU discharge, 216 elderly were followed at 1, 6, 12 months; the one-year cumulative mortality was 49% from ICU discharge, majority of deaths occurring over the first month. Age, previous health status and SAPS had a predictor value of one-year mortality for ICU survivors. 103 patients were alive at one year: 88% returned to home, 72% had a relatively good functional status allowing an independent life, and 82% had the same or improved functional status.

The cosmetic use of skin-lightening products during pregnancy in Dakar, Senegal: a common and potentially hazardous practice

Many women of childbearing age from sub-Saharan Africa use topical skin lighteners, some of which present a risk of toxic systemic effects. The goals of this study were to evaluate, in this environment, the frequency of this practice during pregnancy, as well as eventual consequences on pregnancy. Ninety-nine women from 6 to 9 months pregnant were randomly selected among those attending a standard maternal centre in Dakar for a prenatal visit. Investigations consisted of questions about the use of skin lighteners, a standard clinical examination, follow-up until delivery and a morning blood sample for plasma cortisol levels. Sixty-eight of the 99 selected women used skin lighteners during their current pregnancy, the main active ingredients being hydroquinone and highly potent steroids (used by 64 and 28 women, respectively). No difference in the main outcomes of pregnancy were found between skin-lightener users and the others; however, women using highly potent steroids, when compared with those who did not, had a statistically significant lower plasma cortisol level and a smaller placenta, and presented a higher rate of low-birth-weight infants. Skin lightening is a common practice during pregnancy in Dakar, and the use of steroids may result in consequences in the mother and her child.

Evoked otoacoustic emissions in newborn hearing screening

Evoked otoacoustic emissions (EOEs) were recorded in a group of normally hearing neonates (n = 100 ears) to study the basic properties of EOEs and the parameters influencing them. The results obtained with EOE recordings were compared with those of behavioral screening investigations. The main properties of EOEs in neonates are: 1. EOEs can be recorded in 98% of the tested ears or neonates; 2. there were no statistically significant variations in EOE detection thresholds of neonates between the ages of 1 and 4 days; 3. no statistical difference in the EOE threshold was found between males and females; 4. all EOEs exhibited a broadband spectrum with high-component frequencies; 5. EOEs demonstrating narrowband frequency peaks super-imposed on the broadband component had detection thresholds lower than EOEs without narrowband frequency peaks. EOEs can be used as a screening test. The main clinical interest of this test is to detect the presence (i.e., normal auditory peripheral function) or the absence (i.e., pathological peripheral auditory function) of EOEs in response to a 30-dBHL click stimulation. The results of this study have important applications concerning the possible clinical use of EOEs for screening peripheral auditory dysfunction in neonates.

Seasonal home range size and philopatry in two northern white-tailed deer populations

From 1994 to 1997, we compared summer and winter space utilisation by two white-tailed deer (Odocoileus virginianus) populations wintering in adjacent areas in southeastern Quebec characterised by deep snow cover. One population lived at low density (10 deer/km2) with access to abundant forage in winter (127 000 twigs/ha), whereas for the other, high-density population (20 deer/km2), forage availability was reduced (68 000 twigs/ha). Because of intraspecific competition for resources, we predicted that deer in the high-density population would have smaller home ranges, would exhibit greater philopatry, and would be more likely to disperse. Deer from both populations occupied summer home ranges that were similar in size (1182 ha for adult males; 1102 ha for adult females; 6033 ha for yearling males; 2528 ha for yearling females) but much larger than home ranges observed elsewhere in North America. The high-density population showed a higher level of philopatry than the low-density population during winter but not during summer. Most deer remained migratory during the study (n = 93) but 4 of the 5 that dispersed were from the high-density population. We speculate on the ability of white-tailed deer populations facing severe winters to adapt to using large home ranges in summer. Our results shed light on how wintering areas appear and expand.

Use of temporal envelope cues by children with developmental dyslexia

This study evaluates the ability to process auditory temporal-envelope cues in a group of 6 children with dyslexia (mean age: 10;10 years;months). To address this issue, we measured (a) temporal modulation transfer functions (TMTFs), that is, the detection thresholds of sinusoidal amplitude modulation (SAM) applied to a white noise carrier, as a function of modulation frequency, fm (fm was 4, 16, 64, 256, and 1,024 Hz) and (b) identification performance for vowel-consonant-vowel (VCV) stimuli over 5 sessions. VCV stimuli were either unprocessed or digitally processed to remove the original spectral information, resulting in a time-varying speech envelope amplitude modulating a noise carrier. The same tests were conducted in 6 normal control children (mean age: 11;6 years;months) and 6 normal control adults (mean age: 24;8 years;months). SAM thresholds were similar in normal children and adults. For both normal groups, TMTFs were low pass in shape and showed low between-listener variability. TMTFs measured in children with dyslexia showed higher between-listener variability: TMTFs were band pass in 2 children, flat in 1 child, and low pass in the 3 others. Overall, SAM thresholds were higher in children with dyslexia than in normal children at fm = 4 and 1,024 Hz. Unprocessed-speech identification performance was nearly perfect in normal children and adults, and impaired in children with dyslexia. "Speech-envelope noise" identification performance was poorer in normal children and children with dyslexia than in normal adults. Performance improved across sessions in normal children and adults, but remained constant in children with dyslexia. Compared to normal children, children with dyslexia showed poorer reception of voicing, manner, and place of articulation for unprocessed speech and poorer reception of voicing for "speech-envelope noise." Taken together, these results support the hypothesis that some children with dyslexia may show abnormal auditory temporal-envelope processing. Such a deficit, in turn, may explain the difficulties of children with dyslexia with speech perception.

Placental malarial infection as a risk factor for hypertensive disorders during pregnancy in Africa: a case-control study in an urban area of Senegal, West Africa

In tropical countries, malaria and hypertension are common diseases of pregnancy. They have physiopathologic similarities such as placental ischemia, endothelial dysfunction, and production of proinflammatory cytokines. Recent findings suggested their possible link. The authors conducted a case-control study to explore the relation between malaria and hypertension at Guediawaye, a hypoendemic malarial setting in Senegal. Cases were pregnant women admitted to the delivery unit for hypertension. Controls were pregnant women admitted for normal delivery, without any history of hypertension or proteinuria during the present pregnancy. Malarial infection was determined by placental tissue examination. From January to December 2002, 77 cases of gestational hypertension, 113 cases of preeclampsia, 59 cases of eclampsia, and 241 controls were enrolled. Placental malarial infection (PMI) was present in 14 cases (6.3%) and in 15 controls (6.2%). The prevalence of PMI was 4.6% for eclampsia, 4.0% for preeclampsia, and 11.6% for gestational hypertension. In multivariate analysis, PMI appeared to be an independent risk factor for gestational hypertension (adjusted odds ratio = 2.7, 95% confidence interval: 1.0, 7.6). The authors found an association between PMI and nonproteinuric hypertension in women living in a malaria-hypoendemic area. The exact significance of such relation should be clarified in further studies in different settings of malarial endemicity.

Maternal morbidity and mortality in two different populations of Senegal: a prospective study (MOMA survey)

OBJECTIVE

To compare maternal morbidity and mortality in two urban populations with contrasting availability of health care, and to test the hypothesis that differences in maternal outcome result mainly from the management of delivery in health facilities.

DESIGN

A population-based study of a cohort of pregnant women which was part of a multicentre study of maternal morbidity in six countries of western Africa (MOMA).

SETTING

Two different urban areas of Senegal (Saint-Louis and Kaolack).

POPULATION

3,777 pregnant women who were followed up throughout pregnancy, delivery and puerperium.

MAIN OUTCOME MEASURES

Maternal morbidity and mortality: morbidity was assessed from women's recall at each visit by the investigator and from obstetric complications diagnosed by the birth attendant within health facilities.

RESULTS

Maternal mortality was higher in the Kaolack area where women gave birth mainly in district health care centres, usually assisted by traditional birth attendants, than in Saint-Louis where women giving birth in health facilities went principally to the regional hospital and were usually assisted by midwives (874 and 151 maternal deaths per 100,000 live births, respectively, P < 0 x 01). Maternal morbidity, however, was higher in Saint-Louis than in Kaolack area, especially for births in health facilities (9 x 50 and 4 x 84 episodes of obstetric complications per 100 live births, respectively, P < 0 x 01). Univariate and multivariate analyses showed that morbidity was mainly associated with the training of the birth attendant in facility deliveries and that antenatal care had no effect.

CONCLUSION

Midwives in health facilities appear to detect more obstetric complications than traditional birth attendants. Immediate detection leads to immediate care and to low fatality rates. This could explain differences in maternal outcome between two urban centres with contrasting health care availability. These results suggest that one of the strongest weapons in the fight against maternal mortality is the employment of the most qualified personnel possible for monitoring labour.

Effect of a single session of transcranial direct-current stimulation combined with virtual reality training on the balance of children with cerebral palsy: a randomized, controlled, double-blind trial

[Purpose] The aim of the present study was to investigate the effects of a single session of transcranial direct current stimulation combined with virtual reality training on the balance of children with cerebral palsy. [Subjetcs and Methods] Children with cerebral palsy between four and 12 years of age were randomly allocated to two groups: an experimental group which performed a single session of mobility training with virtual reality combined with active transcranial direct current stimulation; and a control group which performed a single session of mobility training with virtual reality combined with placebo transcranial direct current stimulation. The children were evaluated before and after the training protocols. Static balance (sway area, displacement, velocity and frequency of oscillations of the center of pressure on the anteroposterior and mediolateral axes) was evaluated using a force plate under four conditions (30-second measurements for each condition): feet on the force plate with the eyes open, and with the eyes closed; feet on a foam mat with the eyes open, and with the eyes closed. [Results] An increase in sway velocity was the only significant difference found. [Conclusion] A single session of anodal transcranial direct current stimulation combined with mobility training elicited to lead to an increase in the body sway velocity of children with cerebral palsy.

Tumor necrosis factor-alpha-induced cell killing and activation of transcription factor NF-kappaB are uncoupled in L929 cells

The induction of transcription factor NF-kappaB has been shown to counteract tumor necrosis factor (TNF)-alpha-induced cell death in various cell types. In this study, we investigated the role of NF-kappaB for TNF-alpha-triggered cell death in the widely used mouse cell line L929 by various approaches. Inhibition of the mitochondrial permeability transition by bongkrekic acid impaired TNF-alpha-induced cell death without affecting the activity of NF-kappaB. The reduction of NF-kappaB-mediated gene expression by the synthetic steroid dexamethasone was associated with a decrease in TNF-alpha-mediated cell killing, suggesting that NF-kappaB does not protect L929 cells from TNF-alpha-induced cell death. This concept was reinforced by experiments employing L929 cell lines stably overexpressing a transdominant negative form of IkappaB-alpha. These cell lines were unable to activate NF-kappaB and to inducibly express the IL-6 gene, but they showed the same susceptibility toward TNF-alpha-mediated cell death as L929 wild-type cells.

Effect of chronic ethanol administration on bromobenzene liver toxicity in the rat

Female Sprague-Dawley rats were pair-fed a nutritionally adequate liquid diet containing either ethanol or isocaloric carbohydrate for 3 weeks. In vitro studies showed that chronic ethanol pretreatment preferentially increased the liver microsomal biotransformation of bromobenzene to p-bromophenol (via the toxic 3,4-epoxide) rather than to o-bromophenol (via the nontoxic 2,3-epoxide) and could thus potentiate bromobenzene hepatotoxicity. Bromobenzene administration (500 mg/kg body weight, ip), after an overnight fast, was associated in ethanol-pretreated rats with greater and accelerated liver glutathione depletion and subsequent decrease in liver cytochrome P-450 content than in controls. As assessed histologically and by determination of the rise in activities of serum enzyme markers of liver necrosis, chronic ethanol pretreatment, however, mainly resulted in earlier onset and resolution of bromobenzene-induced liver necrosis, with only a mild increase in the maximal severity of liver lesions. These results suggest that the twofold increase in liver microsomal bromobenzene 3,4-epoxidation by ethanol, being much less than that seen after phenobarbital pretreatment in our animal model and in that of others, is apparently not sufficient to markedly affect the severity of bromobenzene-induced liver toxicity.

Effect of virtual reality training on walking distance and physical fitness in individuals with Parkinson's disease

OBJECTIVE

To evaluate the effects of gait training with virtual reality (VR) on walking distance and physical fitness in individuals with Parkinson's Disease (PD).

METHODS

Thirty-seven individuals with PD participated in this prospective, randomized, controlled clinical trial. They were randomly allocated to a control group submitted to conventional training (n = 12), a treadmill group submitted to gait training on a treadmill (n = 13) and a VR group submitted to gait training using the XboxTM (n = 12). Clinical measures, gait variables and the Six-Minute Walk Test (6MWT) were evaluated: pre-intervention, after one intervention session, post-intervention and follow up (30 days after intervention).

RESULTS

The VR and treadmill groups travelled longer distances on the 6MWT and had faster gait speed in comparison to the control group. The VR and treadmill groups demonstrated an increase in pre-6MWT HR. The VR group had more intense HR after the first session and throughout training, but these gains were not maintained at the follow-up.

CONCLUSION

The present findings demonstrate that gait training with a VR program is as effective as treadmill training with regard to gains in walking distance and improvements in temporal gait variables in individuals with PD.

Effect of aspirin in pregnant women is dependent on increase in bleeding time

OBJECTIVES

Randomized trials with low-dose aspirin to prevent preeclampsia and intrauterine growth restriction have yielded conflicting results. In particular, 3 recent large trials were not conclusive. Study designs, however, varied greatly regarding selection of patients, dose of aspirin, and timing of treatment, all of which can be determinants of the results. Retrospectively analyzing the conditions associated with failure or success of aspirin may therefore help to draw up new hypotheses and prepare for more specific randomized trials.

STUDY DESIGN

We studied a historical cohort of 187 pregnant women who were considered at high risk for preeclampsia, intrauterine growth restriction, or both and were therefore treated with low-dose aspirin between 1989 and 1994. Various epidemiologic, clinical, and laboratory data were extracted from the files. Univariate and multivariate analyses were performed to search for independent parameters associated with the outcome of pregnancy.

RESULTS

Age, parity, weight, height, and race had no influence on the outcome. The success rate was higher when treatment was given because of previous poor pregnancy outcomes than when it was given for other indications, and the patients with successful therapy had started aspirin earlier than had those with therapy failure (17.7 vs 20.0 weeks' gestation, P =.04). After multivariate analysis an increase in Ivy bleeding time after 10 days of treatment by >2 minutes was an independent predictor of a better outcome (odds ratio 0.22, 95% confidence interval 0.09-0.51). Borderline statistical significance was observed for aspirin initiation before 17 weeks' gestation (odds ratio 0.44, 95% confidence interval 0.18-1. 08). Abnormal uterine artery Doppler velocimetric scan at 20-24 weeks' gestation (odds ratio 3.31, 95% confidence interval 1.41-7.7), abnormal umbilical artery Doppler velocimetric scan after 26 weeks' gestation (odds ratio 37.6, 95% confidence interval 3.96-357), and use of antihypertensive therapy (odds ratio 6.06, 95% confidence interval 2.45-15) were independent predictors of poor outcome.

CONCLUSIONS

Efficacy of aspirin seems optimal when bleeding time increases >/=2 minutes with treatment, indicating a more powerful antiplatelet effect. This suggests that the dose of aspirin should be adjusted according to a biologic marker of the antiplatelet effect. A prospective trial is warranted to test this hypothesis.

Protection by organic ions against DNA damage induced by low energy electrons

It is well known that electrons below 15 eV induce strand breaks in DNA essentially via the formation of transient anions which decay by dissociative electron attachment (DEA) or into dissociative electronics states. The present article reports the results of a study on the influence of organic ions on this mechanism. tris and EDTA are incorporated at various concentrations within DNA films of different thicknesses. The amino group of tris molecules and the carboxylic acid function of ethylenediamine tetra-acetic acid (EDTA) molecules together can be taken as simple model for the amino acids components of proteins, such as histones, which are intimately associated with the DNA of eukaryotic cells. The yield of single strand breaks induced by 10 eV electrons is found to decrease dramatically as a function of the number of organic ions/nucleotide. As few as 2 organic ions/nucleotide are sufficient to decrease the yield of single strand breaks by 70%. This effect is partly explained by an increase in multiple inelastic electrons scattering with film thickness but changes in the resonance parameters can also contribute to DNA protection. This can occur if the electron captures cross section and the lifetime of the transient anions (i.e., core-excited resonances) formed at 10 eV are reduced by the presence of organic ions within the grooves of DNA. Moreover, it is proposed that the tris molecules may participate in the repair of DNA anions [such as G(-H)(-)] induced by DEA on DNA bases.

Steindler and pectoralis major flexorplasty: a comparative analysis

Previously published studies on transfers to restore elbow flexion have rarely compared the outcomes among different techniques. We found no comparison between the Steindler procedure and pectoralis major tendon transfer. This study compared functional outcomes after these two types of elbow flexorplasty performed in conjunction with shoulder arthrodesis for patients with brachial plexus injuries. The same examiner assessed 14 patients who underwent shoulder fusion and elbow flexorplasty. Five had a pectoralis major tendon transfer, and nine underwent a modified Steindler procedure. All patients had brachial plexus lesions that were irreparable or had not responded to neurolysis, repair, or grafting. Average follow-up time was 60 months (range, 12 months-10 years). All patients completed a questionnaire (pain, function) and underwent an objective assessment of range of motion, isometric strength, isotonic power, grip, and pinch strength. The BTE Work Simulator (Baltimore Therapeutic Equipment, Hanover, MD) was used for muscle strength testing. Improvement was noted in daily activities including dressing and bilateral activities and was reflected in a significant improvement over preoperative function. No differences (at p = .05 level of significance) were found in objective tests between the pectoralis major transfer and the Steindler groups. In the patient requiring stabilization of the shoulder and flexorplasty, the pectoralis major tendon transfer was at least equivalent to the modified Steindler flexorplasty in terms of range of motion, strength, and subjective measures.

The V-shaped artifact of the gallbladder wall

Among 20,000 patients who had undergone abdominal or gallbladder sonographic examinations, 36 had a short V-shaped artifact originating from an hyperechoic focus in the gallbladder wall. Associated symptoms were varied and nonspecific. The 10 gallbladders excised because of associated cholelithiasis showed a thickened wall, and seven patients had diverticulosis of the wall with impacted stones. In vitro sonographic examination of five gallbladders reproduced the "V" artifact and showed that it originated from a small intramural cholesterol stone. The V artifact should be distinguished from the larger comet-tail and ring-down artifacts, which arise from metal or gas.