DERIVATION OF LOCAL DIAGNOSTIC REFERENCE LEVELS FOR COMMON ADULT COMPUTED TOMOGRAPHY EXAMINATIONS IN MOROCCAN HOSPITAL.

The purpose was to derive local diagnostic reference levels (LDRLs) for adults common computed tomography (CT) examinations in Moroccan hospital. The data of patients were collected retrospectively from one facility for 2 months period. The proposed LDRLs were defined as 75th percentile of spreads for CT dose index-volume (CTDIvol) and dose length product (DLP). Findings were compared with diagnostic reference levels (DRLs) of France, Australia and Egypt. A total of 259 cases were enrolled including 53% of male and 47% of female. The corresponding LDRLs in terms of CTDIvol (mGy) were 58, 15, 15 and 14 for head, chest, abdomen-pelvis and chest-abdomen-pelvis CT examinations, respectively. For DLP (mGy.cm) were 1298, 944, 1874 and 2026, respectively. The proposed LDRLs for CTDIvol were almost similar to DRLs of Australia, higher than those of France and lower than Egyptian DRLs. In terms of DLP, LDRLs were higher than compared studies with exception of head CT, which were lower and higher for CTDIvol than Egyptian DRLs. The results highlight higher radiation doses during adult CT scans, indicating the need to spread the same investigation regarding other imaging procedures including different radiological examinations across Moroccan hospitals.

Lower sulfurtransferase detoxification rates of cyanide in konzo-A tropical spastic paralysis linked to cassava cyanogenic poisoning.

Using a matched case-control design, we sought to determine whether the odds of konzo, a distinct spastic paraparesis associated with food (cassava) cyanogenic exposure in the tropics, were associated with lower cyanide detoxification rates (CDR) and malnutrition. Children with konzo (N=122, 5-17 years of age) were age- and sex-matched with presumably healthy controls (N=87) and assessed for motor and cognition performances, cyanogenic exposure, nutritional status, and cyanide detoxification rates (CDR). Cyanogenic exposure was ascertained by thiocyanate (SCN) concentrations in plasma (P-SCN) and urine (U-SCN). Children with a height-for-age z-score (HAZNCHS)<-2 were classified as nutritionally stunted. CDR was measured as time required to convert cyanide to SCN, and expressed as ms/µmol SCN/mg protein or as mmolSCN/ml plasma/min. Mean (SD) U-SCN in children with konzo was 521.9 (353.6) µmol/l and was, significantly higher than 384.6 (223.7) µmol/l in those without konzo. Conditional regression analysis of data for age- and sex- matched case-control pairs showed that konzo was associated with stunting (OR: 5.8; 95% CI: 2.7-12.8; p<0.01; N=83 paired groups) and higher U-SCN (OR: 1.1; 95% CI: 1.02-1.20 per 50-µmol increase in U-SCN; p=0.02; N=47 paired groups). After adjusting for stunting and U-SCN, the odds of developing konzo was reduced by 63% (95% CI: 11-85%, p=0.03; N=41 paired groups) for each 5mmol SCN/(ml plasma/min)-increase in CDR. Linear regression analysis indicated a significant association between BOT-2 or KABC-II scores and both the HAZNCHS z-score and the U-SCN concentration, but not the CDR. Our findings provide evidence in support of interventions to remove cyanogenic compounds from cassava prior to human consumption or, peharps, enhance the detoxification of cyanide in those relying on the cassava as the main source of food.

Lower serum levels of selenium, copper, and zinc are related to neuromotor impairments in children with konzo.

We assessed the relationship between key trace elements and neurocognitive and motor impairments observed in konzo, a motor neuron disease associated with cassava cyanogenic exposure in nutritionally challenged African children. Serum concentrations of iron, copper, zinc, selenium, and neurotoxic lead, mercury, manganese, cadmium, and cobalt were measured in 123 konzo children (mean age 8.53 years) and 87 non-konzo children (mean age 9.07 years) using inductively coupled plasma mass spectrometry (ICPMS). Concentrations of trace elements were compared and related to performance scores on the Kaufman Assessment Battery for Children, 2nd edition (KABC-II) for cognition and Bruininks-Oseretsky Test, 2nd edition (BOT-2) for motor proficiency. Children with konzo had low levels of selenium, copper, and zinc relative to controls. Selenium concentration significantly correlated with serum 8,12-iso-iPF2α-VI isoprostane (Spearman r=0.75, p<0.01) and BOT-2 scores (r=0.31, p=0.00) in children with konzo. Elemental deficiency was not associated with poor cognition. Mean (SD) urinary level of thiocyanate was 388.03 (221.75) µmol/l in non-konzo compared to 518.59 (354.19) µmol/l in konzo children (p<0.01). Motor deficits associated with konzo may possibly be driven by the combined effects of cyanide toxicity and Se deficiency on prooxidant mechanisms. Strategies to prevent konzo may include dietary supplementation with trace elements, preferentially, those with antioxidant and cyanide-scavenging properties.

27Al NMR study of the structure of lanthanum- and yttrium-based aluminosilicate glasses and melts.

We have investigated by (27)Al nuclear magnetic resonance spectroscopy some compositions in the Ln(2)O(3)-Al(2)O(3)-SiO2 (Ln = Y or La) ternary phase diagram containing more than 60 mol % of SiO2. One- and two-dimensional high-field (17.6 T) high-speed (30 kHz) magic angle spinning experiments have been performed along with simulations of the spectra to quantify the amount of penta-coordinated aluminum present in those glasses as a function of composition. Very high-temperature experiments have allowed to follow selected samples from 2200 degrees C down to 1700 degrees C and hence to characterize the aluminum coordination state and dynamics in those liquids. The present study re-enforces the current view that "minor" species such as penta-coordinated aluminum are actually present in a considerable amount in aluminosilicate glasses, and high-temperature liquids at and above the charge compensation join. The high-field strength of Y3+ and La3+ reveal, for the first time in glasses, a different mean electric field gradient perceived by the tetra- and penta-coordinated aluminum environments. The movements responsible for the NMR relaxation of aluminum in the high-temperature liquid are shown to be uncorrelated with the movements responsible for the macroscopic shear viscosity. Results obtained both on glasses and in situ at high-temperature suggest a preferential localization of Ln3+ nearby tetra-coordinated aluminum species, with possible formation of tricluster and/or Ln3+ coordination changes.

A propos de l'eau potable dans la zone de sante de Mont Amba

L'accessibilite a l'eau potable dans les zones peripheriques de la ville de Kinshasa apparait faible. La qualite aussi laisse fort a desirer. Les auteurs ont evalue la qualite de l'eau potable a travers la zone de sante du Mont Amba en selectionnant 4 points de prelevements couvrant les differents modes d'approvisionnement: source; puits; et robinets. Les resultats des analyses physico-chimiques et bacteriologiques ont revele que les echantillons d'eau preleves ne satisfont pas pas aux normes tel que definies par l'OMS. Des recommandations ont ete formulees pour ameliorer cette situation

Qualite microbiologique des aliments precuits vendus sur le Campus Universitaire de Kinshasa (Zaire)

Depuis la fermeture des restaurants universitaires au Campus de Kinshasa; des kiosques prives vendent aux etudiants des aliments precuits dans des conditions d'hygienes souvent pauvres. Les auteurs ont evalue la qualite bacteriologique de 50 echantillons des mets preleves dans ces kiosques du 1er novembre 1994 au 24 avril 1995. Les resultats ont montre que 38 pour cent d'echantillons etaient contamines par des enterobacteries pathogenes. Des recommendations sont formulees pour l'amelioration de l'hygiene publique et des denrees alimentaires sur le campus