National mapping of schistosomiasis,soil-transmitted helminthiasis and anaemia in Yemen: Towards better national control and elimination

BackgroundSchistosomiasis (SCH) and soil-transmitted helminthiasis (STH) are known to be endemic in Yemen. However, the distribution of both diseases had not previously been assessed by a well-structured national mapping study covering all governorates. The main aim of this study was, therefore, to map the prevalence of SCH and STH in Yemen in order to better inform implementation of effective national control and elimination interventions. The assessment of the distribution of anaemia was also included as a well-known consequence of infection with both SCH and STH. Secondarily, the study aimed to provide a broad indication of the impact of large-scale treatment on the distribution of infection.Methodology and principal findingsTo achive these aims, 80,432 children (10–14 years old) from 2,664 schools in 332 of Yemen’s 333 districts were included, in 2014, into this national cross-sectional survey. Countrywide, 63.3% (210/332) and 75.6% (251/332) of districts were found to be endemic for SCH and STH respectively. More districts were affected by intestinal than urogenital SCH (54.2% and 31.6% respectively). SCH infection was mostly mild and moderate, with no districts reporting high infection. One quarter (24.4%) of Yemeni districts had high or moderate levels of Ascaris lumbricoides infection. Infection with Trichuris trichiura was the second most common STH (44.9% of districts infected) after A. lumbricoides (68.1%). Hookworm was the least prevalent STH (9.0%).Anaemia was prevalent in 96.4% of districts; it represented a severe public health problem (prevalence ≥ 40%) in 26.5% of districts, and a mild to moderate problem in two thirds of the districts (33.7% and 36.1% respectively).ConclusionThis study provided the first comprehensive mapping of SCH, STH, and anaemia across the country. This formed the basis for evaluating and continuing the national control and elimination programme for these neglected tropical diseases in Yemen.     

Changeability in Retama raetam essential oils chemical composition,antioxidant and antimicrobial properties as affected by the physiological stage

Abstract

Retama raetam essential oils (EOs) composition and biological activities were assessed during three developmental periods. The essential oil yield varied significantly among the developmental stages and the optimal was detected at the fresh fruiting stage (0.34%). In addition, EOs composition varied significantly (p < 0.05) according to the different developmental stages. In fact, 2-Methoxy-4-vinylphenol, linalool, and 1-octen-3-ol were the main compounds in the vegetative, flowering, and the fresh fruiting stages, respectively. Developmental stage had also a strong effect on EOs antioxidant and antimicrobial activities. In fact, during the fresh fruiting stage, IC₅₀ and EC₅₀ values of the antioxidant assays were 2 to 3 times inferior to all others stages. Concerning the determination of the diameter of inhibition, a slight to high antimicrobial activity was revealed against 12 bacteria and 4 yeasts. Once again, EOs from the fresh fruiting stage had higher bactericidal effect than those from the flowering and vegetative ones (IZ varied from 10 to 13 mm). The results of this investigation showed for the first time the high accumulation of EOs at the early stages of fruit development making the fresh fruiting optimal stage for the extraction of powerful antioxidant and antimicrobial EOs.     

Molecular cloning and functional expression of the alpha-scorpion toxin BotIII: pivotal role of the C-terminal region for its interaction with voltage-dependent sodium channels

Alpha scorpion toxins bind to receptor site 3 on voltage-dependent sodium channels and inhibit their inactivation. The alpha-scorpion toxin BotIII is the most toxic protein of Buthus occitanus tunetanus. Its sequence differs only by three amino acid residues from that of AahII, the most active alpha-toxin. Due to their high affinity and selectivity for mammalian sodium channels, BotIII and AahII represent powerful tools for studying the molecular determinants of specificity for voltage-dependent sodium channels. Sequence analysis of BotIII gene has revealed two exons separated by a 381-bp intron and a signal peptide of 19 amino acids. We succeeded in expressing BotIII in significantly higher amounts than AahII the only expressed strict alpha anti-mammalian scorpion toxin reported in the literature. We have also modified specific amino acid residues of BotIII. The recombinant and the natural toxins differ by the amidation of the C-terminal residue. Toxicity and binding experiments indicated: (a) the affinity of rBotIII-OH and rAahII-OH (rBotIII-OH with the 3 mutations R10V, V51L, N64H) for the voltage-dependent sodium channels is reduced compared to the natural toxins. This data revealed the important role of the C-terminal amidation for the biological activity of BotIII and AahII; (b) the single mutation N64H is responsible for the difference of toxicity and affinity between rBotIII-OH and rAahII-OH; (c) the addition of the sequence GR to rBotIII-OH leads to the loss of biological activity. This study is in agreement with the important role attributed to the C-terminal sequence of alpha-toxins in their interaction with sodium channels receptors.     

The effect of time of day on short-term maximal performance in obese and non-obese young men

The purpose of this study was to examine time-of-day effects on short-term performance in obese young men. In a balanced study design, 30 boys were divided into two groups: obese (OG; n = 15) and non-obese (CG; n = 15) groups. Both groups performed anaerobic tests of strength and power (squat-Jump, SJ; counter-movement jump, CMJ; 10-m sprint; and 30-m sprint) at 08:00 and 17:00 h on separate days. The results showed morning–evening differences in all variables in CG, with significant increases at 17:00 h (around the time of peak temperature) in comparison with 08:00 h (p < 0.01) for OG. However, such morning-evening differences were not found in the OG, except for the 30-m sprint. Obesity affects the diurnal variation on performances of 30-m sprint with a significant decrease in the evening for OG of 1.23% (p < 0.01). A correlation between anaerobic performance and oral temperature was observed only in the 30-m sprint test. In conclusion, the findings of the present study indicated that obesity is a problem that can affect circadian rhythms and performance in obese young men; therefore, preventing childhood obesity should become a top priority in efforts to improve performance and health.     

Physiological and biochemical traits involved in the genotypic variability to salt tolerance of Tunisian Cakile maritima

Cakile maritima (family: Brassicaceae) was collected from three provenances belonging to different bioclimatic stages (humid, semi arid and arid) in Tunisia to study their eco‐physiological and biochemical responses to salinity. Seedlings were cultivated on inert sand for 20 days under NaCl treatments (0, 100, 200, 400 mm NaCl). Plant response to salinity was provenance‐ and salt‐dependent. At 100 mm NaCl, growth parameters (leaf biomass, area, number per plant and relative growth rate) were improved in plants from Jerba (originating from arid bioclimatic stage) compared with the control, while growth was reduced in those from Tabarka (from humid area). High salt levels (400 mm NaCl) decreased the plant growth in the three provenances, but plants in Tabarka were the most salt sensitive. The relative salt tolerance of plants from Jerba and Bekalta provenances was associated with low levels of malondialdehyde as well as of electrolyte leakage and endoproteolytic activity. Salt reduced leaf hydration, the decrease in water content being dose‐dependent and more pronounced in Tabarka. Increase in salinity led to significant increase in leaf succulence and decrease in leaf water potential, especially in Jerba plants. The plants from the latter displayed the highest leaf levels of Na⁺ and Cl^?, proline, soluble carbohydrates, soluble proteins, and polyphenols. Overall, the higher salt tolerance of plants from Jerba provenance, and to a lower extent of those from Bekalta, may be partly related to their better capacity for osmotic adjustment and to limit oxidative damage when salt‐challenged.     

Variability of phenolic composition and biological activities of two Tunisian halophyte species from contrasted regions

The present study consists in evaluating the inter- and intraspecific variability of phenolic contents and biological capacities of Limoniastrum monopetalum L. and L. guyonianum Boiss. extracts. Ultimately, they were subjected to HPLC for phenolic identification. Results showed a great variation of phenolic content as function of species and localities. In fact, L. guyonianum extracts (El Akarit) contained the highest polyphenol (57 mg GAE g^?1 DW), flavonoid (9.47 mg CE g^?1 DW) and condensed tannin contents (106.58 mg CE g^?1 DW). These amounts were accompanied by the greatest total antioxidant activity (128.53 mg GAE g^?1 DW), antiradical capacity (IC₅₀ = 4.68 μg/ml) and reducing power (EC₅₀ = 120 μg/ml). In addition, L. monopetalum and L. guyonianum extracts exhibited an important and variable antibacterial activity with a diameter of inhibition zone ranging from 6.00 to 14.83 mm. Furthermore, these extracts displayed considerable antifungal activity. L. monopetalum extracts (Enfidha) showed the strongest activity against Candida glabrata and C. krusei with a diameter exceeding 12 mm. The phytochemical investigation of these extracts confirmed the variability of phenolic composition, since the major phenolic compound varied as a function of species and locality. These findings suggest that these two halophytes may be a new source of natural antioxidants that are increasingly important for human consumption, as well as for agro-food, cosmetic and pharmaceutical industries.     

Antioxidant activity and hepatoprotective potential of Hammada scoparia against ethanol-induced liver injury in rats

The present work was aimed at studying the antioxidative activity and hepatoprotective effects of methanolic extract (ME) of Hammada scoparia leaves against ethanol-induced liver injury in male rats. The animals were treated daily with 35 % ethanol solution (4 g?kg^?1?day^?1) during 4 weeks. This treatment led to an increase in the lipid peroxidation, a decrease in antioxidative enzymes (catalase, superoxide dismutase, and glutathione peroxidase) in liver, and a considerable increase in the serum levels of aspartate and alanine aminotransferase and alkaline phospahatase. However, treatment with ME protects efficiently the hepatic function of alcoholic rats by the considerable decrease in aminotransferase contents in serum of ethanol-treated rats. The glycogen synthase kinase-3 β was inhibited after ME administration, which leads to an enhancement of glutathione peroxidase activity in the liver and a decrease in lipid peroxidation rate by 76 %. These biochemical changes were consistent with histopathological observations, suggesting marked hepatoprotective effect of ME. These results strongly suggest that treatment with methanolic extract normalizes various biochemical parameters and protects the liver against ethanol induced oxidative damage in rats.     

Match analysis of elite adolescent team handball players

The purposes of this study were to examine the activity profile of elite adolescent players during regular team handball games and to compare the physical and motor performance of players between the first and second halves of a match. Activity patterns (video analysis) and heart-rate (HR) responses (telemetry) were monitored in top national-division adolescent players (18 men, aged 15.1 ± 0.6 years) throughout 6 regulation games (25-minute halves with a 10-minute interval). The total distance covered averaged 1,777 ± 264 m per game (7.4% less in the second than in the first half, p > 0.05). Players ran 170 ± 24 m at high intensity and 86 ± 12 m at maximal speed, with 32 ± 6 bouts of running (duration 2.3 ± 0.3 seconds) at speeds > 18 km·h(-1); they stood still for 16% of the playing time. The mean HR during play was 172 ± 2 b·min(-1) (82 ± 3% of maximal HR). Blood lactate concentrations at the end of the first and second halves were 9.7 ± 1.1 and 8.3 ± 0.9 mmol·L(-1), respectively (difference p < 0.05). We conclude that adolescent handball players cover less distance and engage in fewer technical actions in the second half of a match. This indicates that team handball is physiologically very demanding. The practical implication is that coaches should seek to sustain performance in the second period of a game by modifying playing tactics and maximizing both aerobic and anaerobic fitness during training sessions.     

Relationship of plasma leptin and adiponectin concentrations with menopausal status in Tunisian women

To evaluate the effect of menopausal status and body mass index (BMI) on circulating leptin and adiponectin concentrations and investigate whether there is an influence of menopausal transition on the relationships of these adipokines and leptin to adiponectin (L/A) ratio with lipid profile and insulin resistance in a sample of Tunisian women. One hundred ninety-six premenopausal (mean age 35.3 ± 7.6 years) and 180 postmenopausal women (mean age 53.4 ± 6.2 years) were included in the study. Participants were stratified into obese and normal weight groups based upon their baseline BMI. Fasting glucose, HDL-cholesterol (HDL-C), triglycerides (TG), total cholesterol (TC), insulin, leptin, and adiponectin concentrations were measured. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Premenopausal women had significantly higher leptin and L/A ratio and lower adiponectin levels than postmenopausal women. Menopause had no effect on the mean values of BMI, insulin or HOMA-IR, HDL-C, and TG. Using a multiple linear regression model, menopausal status was identified, as significant independent predictor for leptin and adiponectin levels. Irrespective of the menopausal status, obese women exhibited higher leptin and L/A ratio and lower adiponectin levels compared to those with normal weight. Comparison between the two menopausal stages in obese and normal weight groups showed that leptin and L/A ratio decreased, while adiponectin increased from pre- to postmenopausal stage only in obese group. The L/A ratio correlated better with lipid profile and HOMA-IR in postmenopausal stage. The present study showed a significant interaction between menopause and BMI on leptin and adiponectin secretion. Menopausal transition affects the relationships of these adipokines with lipids and insulin resistance.     

Effect of subchronic exposure to tetradifon on bone remodelling and metabolism in female rat

This study investigates the effect of subchronic exposure to tetradifon, an organochlorine pesticide with an oestrogen-like structure, in female rat. A single cumulative dose of 2430 mg/kg BW was administrated orally for 12 female rats of 190 g BW. Twelve non-treated additional rats have served as controls. Animals were sacrificed after 6 and 12 weeks of treatment. We studied bone remodelling through histomorphometry and scanning electron microscopy (SEM) analyses. The serum and the right femora were used to determine phosphatase alkaline (AlkP) and/or calcium and phosphorus content. No sign of toxicity was observed until the end of the experiment. The SEM results revealed no structural alteration of the treated animal bone tissue. However, in both treated groups, we have noted an increase in the trabecular distance and a heterogeneous aspect of the endosteum that could be explained by bone-remodelling disturbance, with relative delay of ossification. Following histomorphomotric analysis, these results were coupled with significant increases in Tb.Th and OS/BS. Elsewhere, tetradifon intoxication increased significant serum AlkP level in the group treated for 12 weeks, which could be explained by an osteoblastic hyperactivity. Tetradifon intoxication decreased significantly bone calcium end phosphorus contents. Tetradifon seems not to exert major effects on bone remodelling. However, the osteoblastic hyperactivity could be explained by the oestrogen-like activity of tetradifon and its fatty metabolism. In fact, oestrogen inhibits bone remodelling, and enhances bone formation, which could result in an increase of the osteoid surface and explain the relative delay of ossification.