Multiple melting temperatures of poly(3,3-diethylthietane)

The melting behaviour of semicrystalline poly(3,3-diethylthiethane) (PDET), was studied by differential scanning calorimetry (DSC), wide-angle X-ray scattering (WAXS), small-angle light scattering (SALS), and thermooptical analysis (TOA). Two samples of number-average molecular weights 6,0 · 10⁴ and 1,8 · 10⁵ and rather narrow molecular weight distributions (ratio of weight-to number-average molecular weights M?_w/M?_n = 1,3) were analyzed. When PDET is isothermally crystallized from the molten state in the range 275–333 K, the calorimetric curves show one or two melting endotherms, depending on crystallization temperature (T_c) and heating rate. WAXS analysis shows conclusively that polymorphism is absent. It was shown that the melting behaviour of PDET is being dictated by processes of melting and recrystallization occurring during the experimental analysis.     

Molecular epidemiology of genital Chlamydia trachomatis infection in high-risk women in Senegal, West Africa

The prevalence and heterogeneity of Chlamydia trachomatis infections in a cohort of female sex workers in Dakar (Senegal) were determined by using endocervical-swab-based PCR DNA amplification assays. The overall prevalence of cervical chlamydial infection was 28.5% (206 of 722), and most of these infections were asymptomatic. An increased number of sexual partners was significantly associated with infection (adjusted odds ratio [AOR] = 1.37; 95% confidence interval [CI] = 1.06 to 1.77), while the presence of a yeast infection was negatively associated with chlamydial infection (AOR = 0.28; 95% CI = 0.10 to 0.83). Six different C. trachomatis genotypes were identified based on phylogenetic analysis of the omp1 gene sequences. Interestingly, genotype E predominated (47.6%) and was not associated with visible signs of cervical inflammation compared to non-E genotypes (P < 0.05). Overall, the high rate of asymptomatic C. trachomatis infection by genotype E may suggest genotype-specific properties that confer a transmission advantage in this high risk population.     

Chlorination of polyethylene single crystals

Chlorination under mild conditions of suspensions of polyethylene single crystals demonstrated that a selective attack on the fold surface takes place. Two polyethylene molecular weight fractions (M_n = 47000 and M_n = 150 000) were used and single crystals were grown isothermally from p-xylene at 88°C. The chlorine content was changed from 4 wt.-% to 30 wt.-% and to this level no evidence for crystal attack and loss of crystallinity was found. The melting temperatures of chlorinated single crystals decrease with increasing chlorination up to about 15 wt.-% chlorine content and then stay constant for higher chlorine contents. Moreover, the heat of melting of the chlorinated single crystals is constant and is independent of the chlorine content up to 25 wt.-%. These results are compared with those of samples of chlorinated polyethylene recrystallized from solution and from the melt.     

Clear-fluid meningitis in HIV-infected patients in Dakar

This retrospective study was carried out to describe the epidemiological, clinical and aetiological aspects of clear-fluid meningitis among HIV-positive patients admitted at the Infectious Diseases Clinic in Fann Teaching Hospital in Dakar Data were collected for analysis from patients files recorded from January 1, 2001 to December 31, 2003. Forty-six cases of clear-fluid meningitis were found among HIV-infected patients, representing 51.7% of cerebro-meningeal diseases and 92% of meningitis encountered in those patients. Sex ratio MIF was 1.5 and the mean age of patients was 40.7 years [range 23-61 years]. Clinical presentations comprised headache (80%), fever (67%), meningeal syndrome (74%), coma (28%), convulsions (9%), focal neurological deficits (11%), cranial nerves dysfunction (9%). Aetiologies were represented by neuromeningeal cryptococcosis (29 cases) and tuberculous meningitis (5 cases). In 26% of cases no aetiology was found. The case fatality rate was 63% overall (29 deaths) and 83.3% among cases with unknown aetiology. It did not vary significantly according to epidemiological and clinical variables studied. Neurological sequelae were found in 4 patients who recovered. A better management of clear-fluid meningitis among HIV-positive patients should benefit from the reinforcement of our diagnostic capacities, the availability of effective systemic antifungal drugs and the prevention of opportunistic infections in the course of HIV/AIDS infection.     

Intramuscular distribution of nerves in the human triceps surae muscle: anatomical bases for treatment of spastic drop foot with botulinum toxin

Recent progress has been made in selective functional treatment of hypertonia of spastic origin by local injection of botulinum toxin into the muscles responsible for equinus foot dynamic deformation. The technical aspect of the intervention requires a strategy adapted to the individual patient. Good practice is founded on precise knowledge of the intramuscular nerve distribution of end plate zones, since the target organ of the toxin is the motor end plate. Knowledge about the location of motor end plates, which differs according to the structure of the muscle in question, remains rather poor. Through macroscopic and stereoscopic microscopic dissection of the nerve courses in the triceps surae muscular group in 40 legs, we have ascertained in more detail the distribution of motor end plates, which appear to be more numerous in certain zones of the muscle bellies. These zones were measured morphometrically and divided into segments which are expressed in percentages of a standard leg length. We maintain that these zones are the injection sites most likely to guarantee the best treatment efficacy.     

Bloodless emergent laparotomy for acute abdominal syndrome

Bloodless laparotomy (BL) is defined as an opened exploration of the abdominal cavity that yields negative results, i.e., "provides no information as to the cause of the clinical and paraclinical symptoms responsible for prompting the surgical investigation". The authors report a retrospective study spanning January 1975 to December 1989, on the incidence of and mortality associated with emergent BL in patients with acute abdominal syndrome, with the intent of reducing its frequency. Over this period, 24 BL occurred in 3480 emergent laparotomies, i.e., 0.63%. These involved 7 men, 5 women, 5 boys and 7 girls, aged 4 to 52 years (mean age = 19.5 years). Indications for surgery were based on clinical signs, as well as on laboratory findings such as chest X-ray and plain radiography and needle-puncture of the abdomen. Surgical data indicated:liver cirrhosis--3 cases; mesenteric adenopathy--3 cases; intestinal parasitosis--1 case; bilateral adnescitis--1 case; polycystic ovaries--1 case; wall abscess--1 case; unexplained pain--14 cases. The mortality rate was 2/24. Use of other paraclinical investigations, namely ultrasonography, laparoscopy and peritoneal lavage, and of computer science methods after a prior clinical examination initiated by history-taking, might help reduce the rate of BLs, which are non-devoid of mortality.     

État des lieux du réseau d’alerte des troubles du spectre autistique en Guyane française

Background

Autism spectrum disorders (ASD) are one of the most frequent developmental disorders in childhood. However, in French Guiana the number of children with a diagnosis of ASD remains low. The aim of the study was to describe the perceptions, knowledge and attitudes of a sample of the network of professionals working in contact with small children and thus in a position to alert specialists to developmental anomalies. The aim of the study was to describe the perceptions, knowledge and attitudes of a sample of the network of professionals dealing with the screening of ASD.

ETO2-GLIS2 Hijacks Transcriptional Complexes to Drive Cellular Identity and Self-Renewal in Pediatric Acute Megakaryoblastic Leukemia

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