Detection of Water and Sediments Pollution of An Arid Saltern (Sfax, Tunisia) by Coupling the Distribution of Microorganisms With Hydrocarbons

We investigated the coupling of abundance of bacteria, phytoplankton and ciliates with hydrocarbons in the surface water and sediments of five interconnected ponds in the arid Sfax solar salterns. This study aimed at determining the potential sources of hydrocarbons and the effects of salinity gradients on microorganism metabolism. Hydrocarbon analysis was performed by gas chromatography (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The GC-FID allowed the detection of aliphatic hydrocarbons and n-alkanes ranging from n-C₁₃ to n-C₃₀. Total aliphatic hydrocarbon concentrations varied from 92.5 mg. l^?1 in the first pond (having marine characteristics) to 661.1 mg. l^?1 in the last pond (crystallizer) (316.8?±?120.1 mg. l^?1) for water samples and from 26.7 to 127.8 μg. g^?1 dry weight for sediment samples. The GC-MS enabled us to detect halogenated hydrocarbons (bromoalkanes and chloroalkanes) and n-alkenes. The distribution of n-alkanes indices coupled to several environmental factors suggests that a major fraction of hydrocarbons resulted from both prokaryotic (bacteria) and eukaryotic (protists) developments. A low hydrocarbon fraction might be petrogenic.     

Biological control of the tick fowl Argas persicargas persicus by the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae

The pathogenicity of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae against the tick fowl Argas persicargas persicus was studied. Bioassays revealed significant differences between the two fungi and the A. persicargas persicus stages exposed. The first nymphal instar was more highly susceptible to both fungi than the second nymphal instar. The unfed female of A. persicargas persicus was significantly less susceptible to both fungi than the engorged female. Application of M. anisopliae to sackcloth naturally infested with the tick fowl A. persicargas persicus induced mortality which reached 100% three weeks after treatment under field conditions. The present study suggests that entomopathogenic fungi have good potential for tick fowl, A. persicargas persicus, control.     

Mucometra with Persistent Corpus Luteum in Goats

Ovaries of two goats with persistent corpus luteum were studied by histochemical methods. Lutein cells showed moderate alkaline phosphatase and acid phosphatase activity associated with strong delta 5-3β-hydroxysteroid dehydrogenase and succinic tetrazolium reductase activity. The results are interpreted as an indication that the corpus luteum was functioning.     

Variation in surface conductance to water vapor diffusion in peach fruit and its effects on fruit growth assessed by a simulation model

Surface conductance to water vapor diffusion was measured in individual peach fruits (Prunus persica (L.) Batsch) and plotted as a function of fresh fruit mass for four cultivars. Surface conductance increased with fresh fruit mass, but the pattern differed with cultivar, and fruit-to-fruit variation occurred. Relationships between fruit mass and surface conductance were modeled by fitting mathematical equations to the data. The simulation model of Fishman and Génard (1998) was used to study dry mass and water components of fruit growth (1) when surface conductance varied with fruit size or was constant, and (2) when surface conductance values were high, moderate or low with respect to fruit mass. Increased surface conductance with fresh fruit mass resulted in fruit growth cessation. Fruits differing in surface conductance had similar dry mass. However, under well-watered conditions (stem water potential between -1 and -0.2 MPa), the water balance components of growth (osmotic and hydrostatic pressure, water potential and water balance) differed greatly and, as a result, the lower the surface conductance the greater the fresh fruit mass. These differences were buffered under drought conditions (stem water potential between -2.4 and -0.6 MPa).     

Anticancer Effects of New Ceramides Isolated from the Red Sea Red Algae Hypnea musciformis in a Model of Ehrlich Ascites Carcinoma: LC-HRMS Analysis Profile and Molecular Modeling

Different classes of phytochemicals were previously isolated from the Red Sea algae Hypnea musciformis as sterols, ketosteroids, fatty acids, and terpenoids. Herein, we report the isolation of three fatty acids—docosanoic acid 4, hexadecenoic acid 5, and alpha hydroxy octadecanoic acid 6—as well as three ceramides—A (1), B (2), and C (3)—with 9-methyl-sphinga-4,8-dienes and phytosphingosine bases. Additionally, different phytochemicals were determined using the liquid chromatography coupled with electrospray ionization high-resolution mass spectrometry (LC-ESI-HRMS) technique. Ceramides A (1) and B (2) exhibited promising in vitro cytotoxic activity against the human breast adenocarcinoma (MCF-7) cell line when compared with doxorubicin as a positive control. Further in vivo study and biochemical estimation in a mouse model of Ehrlich ascites carcinoma (EAC) revealed that both ceramides A (1) and B (2) at doses of 1 and 2 mg/kg, respectively, significantly decreased the tumor size in mice inoculated with EAC cells. The higher dose (2 mg/kg) of ceramide B (2) particularly expressed the most pronounced decrease in serum levels of vascular endothelial growth factor -B (VEGF-B) and tumor necrosis factor-α (TNF-α) markers, as well as the expression levels of the growth factor midkine in tumor tissue relative to the EAC control group. The highest expression of apoptotic factors, p53, Bax, and caspase 3 was observed in the same group that received 2 mg/kg of ceramide B (2). Molecular docking simulations suggested that ceramides A (1) and B (2) could bind in the deep grove between the H2 helix and the Ser240-P250 loop of p53, preventing its interaction with MDM2 and leading to its accumulation. In conclusion, this study reports the cytotoxic, apoptotic, and antiangiogenic effects of ceramides isolated from the Red Sea algae Hypnea musciformis in an experimental model of EAC.     

Modulation of growth performances,survival, digestive enzyme activities and intestinal microbiota in common carp (Cyprinus carpio) larvae using short chain fructooligosaccharide

This study investigates the effects of inclusion of low levels of dietary short chain fructooligosacchairde (sc‐FOS) on physiological response and intestinal microbiota of carp (Cyprinus carpio) larvae. After acclimation, fish (550 ± 20 mg) were allocated into nine tanks (40 fish per tank) and triplicate groups were fed a control diet (0%) or diets containing 0.5% and 1% sc‐FOS for 7 weeks. At the end of the experiment, the growth performance parameters (final weight, weight gain, specific growth rate (SGR), food conversion ratio (FCR) and condition factor (CF), survival rate as well as digestive enzyme activities (amylase, lipase and protease), total viable counts of heterotrophic aerobic bacteria (TVC) and lactic acid bacteria (LAB) level in intestinal microbiota were measured. Our results revealed no significant (P > 0.05) effects of sc‐FOS on growth performance and TVC when compared with the control group. However, administration of low levels of dietary sc‐FOS significantly increased digestive enzyme activities (lipase and amylase) and LAB levels (P < 0.05). Also, survival rate was significantly elevated in sc‐FOS fed carp. These results revealed that administration of low levels of sc‐FOS can be considered as a beneficial dietary supplement for larval stage of common carp.     

Identification,diversity and host specificity of the wood-decay fungi in major sawmill depots of north-eastern Bangladesh

The study was carried out to identify wood-decay fungi, and quantify the diversity and host preferences of the fungi in major sawmill depots in north-eastern Bangladesh. A total of 23 fungal species belonging to 15 genera in seven families were recorded and identified. The Polyporaceae was the most dominant family, while Schizophyllum commune was the most abundant species among all species recorded. Other commonly observed fungal species were Daldinia concentrica, Trametes versicolor, Trametes coccinea and Flavodon flavus. The Simpson diversity index (0.93) and Shannon–Wiener index (2.90) showed a wide distribution of the wood-decay fungi in the study areas. The species diversity index (0.036), species evenness index (0.92) and species richness index (3.40) indicated a diverse distribution of the fungal species. Two-thirds of the identified fungal species showed significant preferences for their hosts. The host vulnerability was found to be significantly affected by storage facility, duration of storage, depot yard condition, treated or non-treated wood and shade facility. The findings of this work may help sawmill owners to utilize a scientific approach to management of logs and timber stored in depots, to minimize fungal decay before incurring any economic loss.     

Dyslexia: cultural diversity and biological unity

The recognition of dyslexia as a neurodevelopmental disorder has been hampered by the belief that it is not a specific diagnostic entity because it has variable and culture-specific manifestations. In line with this belief, we found that Italian dyslexics, using a shallow orthography which facilitates reading, performed better on reading tasks than did English and French dyslexics. However, all dyslexics were equally impaired relative to their controls on reading and phonological tasks. Positron emission tomography scans during explicit and implicit reading showed the same reduced activity in a region of the left hemisphere in dyslexics from all three countries, with the maximum peak in the middle temporal gyrus and additional peaks in the inferior and superior temporal gyri and middle occipital gyrus. We conclude that there is a universal neurocognitive basis for dyslexia and that differences in reading performance among dyslexics of different countries are due to different orthographies.     

Stimulation of Ca2+ uptake into micropropagated potato plantlets by UV light and vitamin D3

Micropropagated potato plantlets (Solanum tuberosum cvs Acadia Russet, Red Gold, Red Pontiac, and Russet Burbank) were used to test the effects of exposure to ultra violet rays (UV) or inclusion of vitamin D₃ (cholecalciferol) in the test solution on plantlet calcium (Ca) uptake. Ca uptake was determined by measuring shoot tissue⁴⁵Ca²⁺ concentration inex vitro plantlets placed into test solutions containing radiolabelled calcium (⁴⁵CaCl₂). Shoot tissue⁴⁵Ca²⁺ concentration was very significantly increased in all cultivars exposed for 24 h to UV treatment compared with control plantlets. This increase in shoot⁴⁵Ca²⁺ concentration was similar (three cultivars) or greater (one cultivar) than that caused by 10 ing L^?1 vitamin D₁ in the test solution. When plantlets were exposed to UV, then placed for 24 h in the dark, significantly greater shoot⁴⁵Ca²⁺ concentrations occurred compared with plantlets tested immediately following treatment. This suggests that a change in the UV-elicited cellular product occurred during the dark interval that promoted more Ca uptake into plantlets.