Assessing the Risk of Birth Defects Associated with Exposure to Fixed-Dose Combined Antituberculous Agents during Pregnancy in Rats

Due to the risks of disease progression and transmission to the newborn, treatment of tuberculosis is often pursued during pregnancy and fixed-dose combined antituberculous agents have been found to be beneficial. Unfortunately, there is paucity of data on the safety of the fixed-dose combined antituberculous drugs during pregnancy. This study intends to assess the teratogenic effect of fixed-dose combined antituberculous drugs on the organogenesis stage of fetal development and also investigate the possible roles of vitamin C in modulating the teratogenic effects of these agents on the fetus using animal model. Pregnant rats were divided into 3 groups with 12 animals per group: group 1 received distilled water (10 mL/kg) orally; group 2 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents orally; group 3 received 51.4 mg/kg/day of fixed-dose combined antituberculous agents plus vitamin C (10 mg/kg/day) orally. Six rats in each group were randomly selected and sacrificed on day 20 by cervical dislocation prior to day 21 of gestation, and the foetuses were harvested through abdominal incision for physical examination. Blood samples were collected from the 1st filial rats of the remaining six animals for biochemical and hematological examination. The liver, kidney, heart, and brain of all the sacrificed animals were used for histopathological examination. There were significant (P ≤ 0.05) low birth weights of the foetuses of the animals that were treated with fixed-dose combined antituberculous agents. The haematological parameters also revealed a reduction in the platelets counts and neutrophiles at the first filial generation. Significant (P ≤ 0.05) elevations in the levels of aspartate aminotransferase (AST) and alkaline phosphatase (ALP) in the foetuses of the animals treated with fixed-dose combined antituberculous agents were also observed. However, the combination of vitamin C with fixed-dose combined antituberculous agents significantly (P ≤ 0.05) reduced the level of AST. Fixed-dose combined antituberculous agents have teratogenic potential as shown in low birth weight and mild liver damage in the first filial of the treated animals. As much as it is imminent to treat TB patients in pregnancy, there is need to always exercise caution and clinically weigh the risk-benefit ratio

Indoor environmental conditions of selected shopping malls in Nigeria: A comparative study of microclimatic conditions, noise levels, and microbial burdens

oai:repository.uel.ac.uk:8x3x4The activities of people and equipment used within shopping malls are major factors that contribute to air pollution and increased sound levels, thereby affecting indoor environmental quality and the well-being of mall operators. This study assessed indoor environmental quality through microbial characterization and measurement of environmental conditions present in selected shopping malls. Investigations were conducted at three shopping malls in Ibadan selected through convenience sampling technique. Environmental parameters such as noise level, relative humidity, temperature, PM₂.₅ levels, total volatile organic compound (TVOC) levels, microbial characterization, and quantity were determined. Microclimatic parameters (temperature and relative humidity) were measured using a 4-in-1 Precision Gold N09AQ multi-tester. Culturable airborne microbes were collected using the settle plate technique. PM₂.₅ and TVOC levels were measured using a Thermo Scientific MIE pDR-1500 PM monitor and sf200-TVOC meter respectively. Two bacteria species and five fungi species were isolated across the malls. The noise levels ranged from 61.27 to 81.20 dB. The mean temperatures (highest mean of 33.44 ± 1.42 °C), PM₂.₅ (highest mean of 114.06 ± 25.64 μg/m³), and TVOC (highest mean of 55.21 ± 8.28 ppm) concentrations were higher than the permissible limits stipulated by the WHO guidelines and NESREA standard limits across all the selected malls. A positive correlation was found to exist between particulate matter and TVOC (r = 0.174, p = 0.004). The total bacteria count was generally high with the highest mean of 1965.33 ± 368.56 CFU/m³, while the total fungi count was generally low with the highest mean of 579.82 ± 51.55 CFU/m³. Bacillus spp. and Candida spp. were found to the consistent from all sample points across the three malls. The bacteria isolated are Gram-positive bacteria associated with human skin which suggests a high rate of indoor pollution from humans. In conclusion, this research has demonstrated the necessity to monitor noise levels and indoor air quality in malls. Also, there is need for government policies to improve indoor air quality which must be enforced and regulated, especially within shopping malls

Evaluation of Pasting Properties of Plantain, Cooking Banana, Selected Cereals and their Composites as Indicators for their Food Values

The pasting properties of unripe plantain, unripe cooking banana, some selected cereals and their composite flours were investigated in relation to their food values. Each of the samples was cleaned, air–dried and pulverized to form the native flours which were mixed in different proportions to form the composite flours. Soft doughs were prepared from the flours and subjected to textural evaluation. The adjudged best from each set was analysed using Rapid Visco–Analyser followed by determination of their proximate composition and functional properties. The results showed that the breakdown viscosity (cP) of each of the composite flours was less than 920.50 in plantain and 915.50 in cooking banana, indicating improved ability to withstand shear stress. The values of the final viscosity of the composite flours were generally lower than the native flours of plantain and cooking banana which indicated better flow property. The setback viscosities of the composite flours were lower than the native cereal flours except sorghum which indicated lower tendency to undergo retro–degradation. Furthermore, the composite flours gelled at lower temperature (72.1–84.9 °C) when compared with the native flours (82.7–89.2 °C) reflecting less energy requirement for cooking. Combination of cereals with plantain or cooking banana had led to production of composite flours which gave better and improved pasting properties without depreciation in functional properties and nutritional composition. Keywords: Composite flour; Cereal–plantain; Cereal–cooking banana; Proximate composition; Functional and pasting properties

Biomacromolecules in Recent Phosphate-Shelled Brachiopods: Identification and Characterization of Chitin Matrix

Abstract: Phosphate-shelled brachiopods differ in filter-feeding lifestyle, with Lingula anatina an active infaunal burrower, and Discinisca tenuis a shallow marine epibenthic animal. The shells of these animals are built of organophosphatic constituents, the organic fibres/sheets reinforced with calcium phosphate to provide a sophisticated ultrastructural robustness. This investigation examined the nature of the organic fibres in order to improve understanding of how living organisms produce hierarchically structured biomaterials. Unlike powdered samples commonly used in previous studies, organic fibres were isolated for the first time and the shell fractions were purified, in order to study the content and nature of the biopolymer fibres. Biochemical methods including Calcofluor staining revealed a chitin matrix. Ultrastructural analysis, thermal gravimetric analysis, and spectroscopic analyses show that the core polysaccharide framework is composed of layers of β-chitin sheets and/or fibrils that are coated with a fibrous organic matrix. There is more chitin matrix in the L. anatina shells (26.6 wt.%) compared to the D. tenuis shells (12.9 wt.%). Taken together, the data show that the chitin matrix contributes to increased skeletal strength, making L. anatina highly adapted for life as an active burrower. In comparison, D. tenuis contains less chitin and lives as attached epibenthos in a shallow marine environment. Graphical abstract: [Figure not available: see fulltext.] First spectroscopic evidence of β-chitin sheets in recent organophosphatic brachiopods. © 2021, The Author(s).OBAA is grateful to Uppsala University for support through the VR Project number 2018-03390. The research for this paper was supported by the Swedish Research Council (VR Project no. 2018-03390 to LEH, GAB and SCG), by the National Natural Science Foundation of China (41720104002, 41621003 and 41890844 to NWU members), and by a Zhongjian Yang Scholarship to LEH from the Department of Geology, Northwest University, Xi’an. GAB’s research is also funded by a 1000 Talent Shaanxi Province Fellowship at Northwest University, Xi’an

SYNTHESIS, CHARACTERIZATION AND ANTIBACTERIAL PROPERTIES OF SOME HETEROLEPTIC METAL(II) COMPLEXES OF PARACETAMOL AND VANILLIN

Objectives: This study was aimed at investigating the suitability of Paracetamol and Vanillin in forming low spin, novel heteroleptic, octahedral metal(II) complexes and the potentials of the metal(II) complexes as broad-spectrum antibacterial agents in-vitro.Methods: Heteroleptic metal(II) complexes of Paracetamol (HL) and Vanillin(HL1) were synthesized and characterized by percentage metal analysis, infrared and electronic spectroscopies, room temperature magnetic moments, melting points, conductance measurements. The antibacterial activity of the synthesized complexes as well as their metal-free ligands was studied using the agar diffusion technique.Results: Infrared spectra data confirmed that coordination was via the Paracetamol and Vanillin phenol and carbonyl oxygen atoms. The room temperature magnetic moment and electronic spectra data indicated that all the metal(II) complexes assumed octahedral geometry. Furthermore, the Ni(II) complex showed high spin  low spin octahedral equilibrium, and the Cu(II) complex was dimeric and antiferromagnetic.  The molar conductances of the metal(II) complexes in DMSO showed that the complexes were covalent. Interestingly, the in-vitro antibacterial studies on these metal(II) complexes, Paracetamol and Vanillin against Bacillus cereus, Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Klebsiella oxytoca and Staphylococcus aureus showed that the Cobalt(II) complex had the best antibacterial activity, being active against all the bacteria used with inhibitory zones range of 19.0-26.0 mm proving it's potentials as a broad spectrum antibacterial agent.Conclusion: Infrared and electronic spectroscopies, with room temperature magnetic moments indicated a monomeric, 6-coordinate octahedral geometry for all the complexes with the exception of the Cu(II) complex, which was dimeric. Keywords: antibacterial, covalent, equilibrium, paracetamol, vanilli

Planktic foraminifera form their shells via metastable carbonate phases

The calcium carbonate shells of planktic foraminifera provide our most valuable geochemical archive of ocean surface conditions and climate spanning the last 100 million years, and play an important role in the ocean carbon cycle. These shells are preserved in marine sediments as calcite, the stable polymorph of calcium carbonate. Here, we show that shells of living planktic foraminifers Orbulina universa and Neogloboquadrina dutertrei originally form from the unstable calcium carbonate polymorph vaterite, implying a non-classical crystallisation pathway involving metastable phases that transform ultimately to calcite. The current understanding of how planktic foraminifer shells record climate, and how they will fare in a future high-CO2 world is underpinned by analogy to the precipitation and dissolution of inorganic calcite. Our findings require a re-evaluation of this paradigm to consider the formation and transformation of metastable phases, which could exert an influence on the geochemistry and solubility of the biomineral calcite

Survival of environmental DNA in sediments: Mineralogic control on DNA taphonomy

Publication status: PublishedThe extraction of environmental DNA (eDNA) from sediments is providing ground‐breaking views of past ecosystems and biodiversity. Despite this rich source of information, it is still unclear which sediments favor preservation and why. Here, we used atomic force microscopy and molecular dynamics simulations to explore the DNA‐mineral interaction to assess how mineralogy and interfacial geochemistry play a role in the preservation of environmental DNA on mineral substrates. We demonstrate that mineral composition, surface topography, and surface charge influence DNA adsorption behavior as well as preservation. Modeling and experimental data show that DNA damage can be induced by mineral binding if there is a strong driving force for adsorption. The study shows that knowledge of the mineralogical composition of a sediment and the environmental conditions can be useful for assessing if a deposit is capable of storing extracellular DNA and to what extent the DNA would be preserved. Our data adds to the understanding of eDNA taphonomy and highlights that, for some mineral systems, fragmented DNA may not represent old DNA

Safety evaluation of green synthesized Cola nitida pod, seed and seed shell extract-mediated silver nanoparticles (AgNPs) using an Allium cepa assay

The increase in the use of nanoparticles in various fields of human endeavours calls for the need to understand the toxic potential of green synthesized nanoparticles. Cytogenotoxic potentials of green synthesized Cola pod (Cp-AgNPs), seed (Cs-AgNPs) and seed shell (Css-AgNPs) silver nanoparticles and silver nitrate salts (Ags) were evaluated using an A. cepa assay. Twenty onion bulbs were exposed to 0.01, 0.10, 1.0, 10.0, and 100.0 μg/ml AgNPs and Ags solutions. Microscopic evaluation was performed at 24, 48 and 72 h with 5000 cells per concentration scored for chromosomal aberrations, while the effects on the root growth were evaluated at 72 h. The observed dividing cells and mitotic inhibition were dose-dependent for the three AgNPs and Ags at 24, 48 and 72 h. Mitotic index obtained for 1.0, 10 and 100 μg/mL at all times of evaluation were less than half the value of the negative control, while cell arrest was only observed at 72 h at a concentration of 100 μg/mL for the three AgNPs. The chromosomal aberrations observed were c-mitosis, a chromosome bridge, a vagrant chromosome, and a sticky chromosome, which indicate the potential of AgNPs for genotoxicity. The mean root length of A. cepa treated with AgNPs showed a dose-dependent significant decrease compared to the control, indicating their inhibitory potential, but the mean root lengths were found to be lower at all concentrations compared to those treated with Ags, thus showing the attenuation of growth inhibition. The EC50 values revealed the order of growth inhibition as Ags>Cp-AgNPs>Css-AgNPs>Cs-AgNPs. The cytogenotoxic potential of the AgNPs suggests that caution should be exercised in their usage to prevent environmental pollution. Keywords: Green synthesis, Nanoparticles, Silver, Aberration, Allium cepa, Cola nitid

Lixisenatide in type 1 diabetes: A randomised control trial of the effect of lixisenatide on post‐meal glucose excursions and glucagon in type 1 diabetes patients

Aims The GLP1 agonist lixisenatide is glucagonostatic and reduces post‐prandial blood glucose (PPBG) in type 2 diabetes. This study investigates its impact in type 1 diabetes (T1D). Methods In a blinded, crossover trial, 25 patients with T1D were randomised to 4 weeks adjunctive treatment with lixisenatide (L) or placebo (P), with a 4‐week washout period. The primary outcome was percentage of 3 hours PPBG in target (4‐10 mmol/L) assessed by CGM before and after treatment. Participants also underwent post‐treatment standardised mixed meal test (MMT, n = 25) and hyperinsulinaemic hypoglycaemic clamp (n = 15). Results PPBG CGM readings in target were similar between L vs P (Mean % ± SE, breakfast 45.4 ± 6.0 vs 44.3 ± 6.0, P = .48, lunch 45.5 ± 5.8 vs 50.6 ± 5.3, P = .27 and dinner 43.0 ± 6.7 vs 47.7 ± 5.6, P = .30). HbA1C was similar between L vs P (64.7 ± 1.6 vs 64.1 ± 1.6 mmol/mol, P = .30). Prandial insulin fell after lixisenatide (dose change −0.7 ± 0.6 vs +2.4 ± 0.7 units/d, P = .004), but basal insulin dose was similar between groups. The post‐MMT glucose area under the curve (AUC) was lower with L than P (392.0 ± 167.7 vs 628.1 ± 132.5 mmol/L × min, P < .001), as was the corresponding glucagon AUC (140.0 ± 110.0 vs 304.2 ± 148.2 nmol/L × min, P < .001). Glucagon and counter‐regulatory hormone values at a blood glucose of 2.4 mmol/L during the hypoglycaemic clamp were similar between L and P. Conclusion In T1D, PPBG values were not altered by adjunctive lixisenatide although prandial insulin dose fell. Glucose and glucagon level during an MMT were significantly lower after lixisenatide, without affecting counter‐regulatory response during hypoglycaemia