Evidence for a recent increase in delivery of atmospheric 210Pb to Oualidia lagoon, coastal Morocco.

Two sediment cores were collected from the Oualidia lagoon, on the Atlantic coast of Morocco, and analyzed for 210Pb and 137Cs activity by gamma spectrometry. The 210Pb profiles were characterized by high activity at specific depths in each core, which were attributed to substantial increases in atmospheric 210Pb input to the sediment. A modified CRS model was applied to develop age-depth relations (chronologies) for the cores and calculate sediment accumulation rates, taking into account changing unsupported 210Pb delivery and specifying the year when the increase began. Calculated 210Pb inventories (activity/area) and fluxes (activity/area/time) depend strongly on sedimentation rates and were much higher than mean values in similar coastal systems worldwide. We attempted to use 137Cs as a time marker to support the modified CRS chronologies for both cores. The 137Cs profiles, however, were affected by post-depositional cesium migration in the sediment which made it difficult to identify the 1963 atmospheric bomb-testing peak, especially in the core with low sedimentation rate. We conclude that the high activities of 210Pb detected at specific depths in the Oualidia lagoon sediment cores are a consequence of decay of radioactive 222Rn, which displayed periodic high concentrations in the overlying atmosphere.

Synthesis of New Binary Thiazole-Based Heterocycles and Their Molecular Docking Study as COVID-19 Main Protease (Mpro) Inhibitors.

Isolated polynuclear binary heterocyclic compounds containing thiazole building block combined with benzofuran, pyrrole, thiazole, or thiophene via carboxamide and/or secondary amine as a junction are presented. The synthetic strategy of those is based on utilization of 2-chloroacetamido-4-phenylthiazole in the synthesis of binary heterocyclic compounds by cyclocondensation with salicylic aldehyde, acetonitrile derivatives, ammonium thiocyanate, 3-mercaptoacrylonitrile derivatives, and/or 3-mercaptoacrylate derivatives. The prepared binary thiazole-based heterocycles have been studied as protease (Mpro) inhibitors by molecular docking for visualization of their orientation and interactions with COVID-19 units using hydroxychloroquine as a reference molecule.

Novel route for amine grafting to chitosan electrospun nanofibers membrane for the removal of copper and lead ions from aqueous medium.

A novel step wise synthetic route was developed to prepare amine grafted nanofibers (AGNFs) affinity membrane. The chemical structure of the nanofibers (NFs) after grafting was studied by acquiring Fourier Transform Infrared (FT-IR) spectra and Carbon, Hydrogen and Nitrogen (CHN) data. The morphology of the NFs before and after grafting was studied by Field Emission Scanning Electron Microscope (FE-SEM). FT-IR and CHN data confirmed the introduction of new functional groups into the primary structure of chitosan (CH). FE-SEM showed denser membrane with no deterioration of the NFs morphology after grafting. The aqueous stability of the membranes was studied in distilled water. The AGNFs membranes showed good aqueous stabilities (with only ∼ 6% loss in weight until 24 h and remained stable thereafter) which was less than the weight loss by glutaraldehyde treated nanofibers (GNFs) (∼44% loss in weight until 24 h) and pristine NFs (100% loss in weight as soon as the NFs were immersed in distilled water). The maximum adsorption (qm) capacity of AGNFs for Cu (II) and Pb (II) was observed to be 166.67 mg.g-1 and 94.34 mg.g-1. The adsorption capacity of the present systems was much higher for Cu (II) when compared to the already existing conventional and chitosan adsorbents. This increased might be related not just to the size, but more potentially to the increase in the number of nitrogen binding sites (chelating sites). Nitrogen donates lone-pair of electrons for chelation. The combination of processing into nano size and amine grafting (AG) has significantly increased the adsorption capacity of CH NFs membrane.

Creatinine, blood urea nitrogen and thyroid hormone levels before and after haemodialysis.

A study was carried out on 57 patients with chronic renal failure in a hospital in Kerman city, Islamic Republic of Iran. Blood samples were taken before and after haemodialysis to measure blood urea nitrogen and serum creatinine, triiodothyronine (T3) and thyroxine (T4) levels. Findings revealed that before dialysis T4 in 11 cases and T3 in 29 cases were lower than the normal range, but after haemodialysis only 3 cases for T4 and 15 cases for T3 were lower than normal levels. The remaining cases reverted to normal state. We suggest that a feedback relationship exists between the major end catabolic products (creatinine and blood urea nitrogen) and thyroid hormone serum levels.

The lethal effects of some onolophosphate insecticides on yeast Saccharomyces cerevisiae.

Thre enolophosphate insecticides (chlorphenvinphos: 0-/-/2',4'-dichlorophenyl/-2-chlorovinyl/diethyl phosphate, bromphenvinphos: 0-/1-/2',4'-dichlorophenyl/-2-bromovinyl/diethyl phosphate, mebromvinphos: 0-/1-/2',4'-dichlorophenyl/-2-bromovinyl/dimethyl phosphate) have been tested for their biological activity in baker's yeast. The results indicate that the chemicals exert an immediate hibitory effect on amino acid transport system, respiration, fermentation and ell growth. Consequently the effect of precipitous cell death also occurred. Furthermore the direct destroying action of the studied chemicals on protoplast as also observed. The main cause of cell death is the development of membrane leakiness. It was found that the loss of sugar transport activity parallels the loss of cell viability. All the studied insecticides showed negligible netic activity.

Cutaneous leishmaniasis in primary school children in the south-eastern Iranian city of Bam, 1994-95.

Between August 1994 and July 1995, 11,517 primary school children aged 6-11 years in the south-eastern Iranian city of Bam, comprising 5560 (48.3%) girls and 5957 (51.7%) boys, were examined for the presence of active lesions or scars of cutaneous leishmaniasis (CL). There was a trend towards increasing prevalence with age, the prevalence being 10.7% in 6-year-old and 20% in > or = 11-year-old children. Overall, 1.3% of the children had active lesions and 14.3% had scars. There was no significant difference between the sexes in the prevalence of active lesions and/or scars. Of the children examined, 54 (0.5%) had leishmaniasis recidivans: 19 girls (35.2%) and 35 boys (64.8%). The number of active lesions or scars per child ranged from 1 to 10. The majority (82.3%) had 1 lesion, 12.4% had 2 lesions, and 5.3% had > or = 3. The average number of lesions was 1.08 (1.03 in girls and 1.18 in boys). The face was the part of the body most commonly involved (63.6%), followed by the hands (20.9%), legs (12.8%) and other parts of the body (2.7%). Examination of isolates from 14 children revealed that in 13 (92.9%) the causal organism was Leishmania tropica and in the other (7.1%) L. major. The survey indicates that the geographical distribution of CL is far wider than previously thought. It also shows that Bam is a suitable areas for a vaccine field trial.

PIP: Cutaneous leishmaniasis, caused by Leishmania tropica, is endemic in southeastern Iran's Kerman Province, including the city of Bam. As a first step toward selecting different arms of a vaccine field trial, all 11,517 primary school students 6-11 years old from Bam were examined between August 1994 and July 1995 for the presence of active lesions or scars of cutaneous leishmaniasis. Overall, 1.3% of children had active lesions and 14.3% had scars. Prevalence tended to increase with age, but there was no difference on the basis of sex. 54 children (0.5%) had leishmaniasis recidivans. The number of active lesions or scars per child ranged from 1 to 10 (average, 1.08). Body parts most frequently affected were the face (63.6%), hands (20.9%), and legs (12.8%). Examinations of isolates from 14 children revealed that L. tropica was the causal organism in 13 (92.9%). These findings indicate that cutaneous leishmaniasis is even more widely distributed throughout Iran than previously thought, probably as a result of agricultural and unplanned urban development. They further confirm that Bam is a suitable location for a vaccine field trial.

Randomised vaccine trial of single dose of killed Leishmania major plus BCG against anthroponotic cutaneous leishmaniasis in Bam, Iran.

BACKGROUND: A vaccine consisting of a single dose of whole-cell autoclave-killed Leishmania major (ALM) mixed with BCG was assessed in comparison with BCG alone against anthroponotic (human to human transmission) cutaneous leishmaniasis in a randomised double-blind trial in Bam, Iran. METHODS: 3637 schoolchildren, aged 6-15 years, with no history of cutaneous leishmaniasis and no response to a leishmanin skin test, were randomly assigned to receive 1 mg ALM mixed with BCG (n = 1839), or BCG alone (n = 1798). Safety of the vaccine and the incidence of confirmed cases of cutaneous leishmaniasis were followed up for 2 years. FINDINGS: Side-effects were those usually associated with BCG vaccination, but tended to persist longer in the ALM + BCG group. After exclusion of four cases occurring within 80 days of vaccination (one in the ALM + BCG group and three in the BCG group), the 2-year incidence of cutaneous leishmaniasis did not differ significantly between vaccine and BCG groups: 2.8% vs 3.3%, respectively (total cases 112). A sex-stratified analysis showed that in boys the vaccine conferred a protective efficacy of 18% and 78% for the first and second years, respectively--a crude 2-year overall protection of 55% (95% CI 19-75%, p < 0.01). In the first 9 months after vaccination, there was a non-significant excess of cases in the ALM + BCG group (25 vs 16), whereas the incidence of cutaneous leishmaniasis thereafter was significantly reduced in the ALM + BCG group (27 vs 44, p < 0.05). INTERPRETATION: A single dose of ALM + BCG was safe and more immunogenic than BCG alone, as measured by leishmanin skin test. The exact reason for the apparent protective effect of the vaccine in boys is unknown, and may be a chance finding. However, since boys are more exposed to the infection, which is indicated by higher disease prevalence in boys in this study population, the preferential protective effect in boys may have resulted from a greater booster effect produced by repeated exposure to infected sandflies. Booster injections or alternative adjuvants should be tried to improve the potential efficacy of this vaccine.

Creatinine, blood urea nitrogen and thyroid hormone levels before and after haemodialysis

A study was carried out on 57 patients with chronic renal failure in a hospital in Kerman city, Islamic Republic of Iran. Blood samples were taken before and after haemodialysis to measure blood urea nitrogen and serum creatinine, triiodothyronine [T3] and thyroxine [T4] levels. Findings revealed that before dialysis T4 in 11 cases and T3 in 29 cases were lower than the normal range, but after haemodialysis only 3 cases for T4 and 15 cases for T3 were lower than normal levels. The remaining cases reverted to normal state. We suggest that a feedback relationship exists between the major end catabolic products [creatinine and blood urea nitrogen] and thyroid hormone serum levels