Differences in COVID-19 Preventive Behavior and Food Insecurity by HIV Status in Nigeria

AIDS and Behavior - The aim of the study was to assess if there were significant differences in the adoption of COVID-19 risk preventive behaviors and experience of food insecurity by people living...     

Hepatoprotective Effect of Cymbopogon Citratus Aqueous Extract Against Hydrogen Peroxide-Induced Liver Injury in Male Rats

Background

Cymbopogon citratus (Poaceae) a tropical perennial herb plant that is widely cultivated to be eaten either fresh with food or dried in tea or soft drink has been reported to possess a number of medicinal and aromatic properties. This study aimed at evaluating the protective effects of C. citratus aqueous extract against liver injury induced by hydrogen peroxide (H₂O₂), in male rats.

Materials and Methods

Twenty-five rats were randomly divided into five different groups of five animals in each group; (1) Control. (2) Received H₂O₂ (0.5%) with drinking water. (3), and (4) received H₂O₂ and C. citratus (100 mg·kg⁻¹ b wt), vitamin C (250 mg·kg⁻¹ b wt) respectively. (5), was given C. citratus alone. The treatments were administered for 30 days. Blood samples were collected and serum was used for biochemical assay including liver enzymes activities, total protein, total bilirubin and malonaldehyde, glutathione in serum and liver homogenates. Liver was excised and routinely processed for histological examinations.

Results

C. citratus attenuated liver damage due to H₂O₂ administration as indicated by the significant reduction (p<0.05), in the elevated levels of ALT, AST, ALP, LDH, TB, and MDA in serum and liver homogenates; increase in TP and GSH levels in serum and liver homogenates; and improvement of liver histo-pathological changes. These effects of the extract were similar to that of vitamin C which used as antioxidant reference.

Conclusion

C. citratus could effectively ameliorate H₂O₂-induced oxidative stress and prevent liver injury in male rats.     

Experimental studies of tumor radioimmunodetection using antibody mixtures against carcinoembryonic antigen (CEA) and colon-specific antigen-p (CSAp)

Experiments with the GW-39 human colonic carcinoma growing in hamsters showed that injection of radioactive antibody to a colorectal-specific, tumor-associated antigen, CSAp, results in better tumor radiolocalization than was seen previously with radioantibodies to carcinoembryonic antigen (CEA). However, a mixture of both radioactive antibodies resulted in potentiation of CEA-tumor radioimmunodetection without affecting CSAp-tumor radiolocalization. Hence, multi-marker antibody mixtures may be the method of choice in cancer radioimmunodetection.     

Nonbactericidal approach to reduce colonization of plaque microflora on teeth in vitro and in vivo

A non-antibacterial, surface-modifying, perfluorosulfonamidoalkyl ester of phosphorous acid (PSAEP, 1) was adsorbed to saliva-coated hydroxyapatite disks in vitro. Pretreatment of saliva-coated hydroxyapatite beads with different concentrations of 1 markedly reduced the adherence of radiolabeled Streptococcus mutans or Actinomyces viscosus when compared with the buffer-treated controls. Pretreatment of the cells with the compound also significantly impaired their subsequent attachment to saliva-coated hydroxyapatite. In a low surface-to-volume ratio adsorption model, i.e., saliva-coated hydroxapatite disks, pretreatment with 1 for 1 min markedly reduced the adsorption of A. viscosus to the disks. A 1% solution applied topically twice a day significantly (alpha = 0.05) reduced S. mutans-induced smooth and fissure caries in rats. The effect of 0.05% 1 in a rinse was also evaluated on experimental gingivitis in beagle dogs for 6 weeks. A topical application twice a day significantly (alpha = 0.05) reduced plaque-induced gingivitis when compared to that achieved with the placebo. Microbial analyses of the plaque adjacent to gingiva indicated reduction in filamentous medium and large spirochetes as compared with that seen in the pretreatment phase. Collectively, the results show that it is possible to reduce dental caries and gingivitis via an interference with the specific adsorption of organisms to teeth.     

Effect of amino acids and dipeptides on accumulation of ammonia in the medium during <Emphasis Type="Italic">in vitro</Emphasis> maturation and fertilization of porcine oocytes

Aim:  The present study was designed to investigate the effect of amino acids and their dipeptides on the accumulation of ammonia in the medium during in vitro maturation (IVM) and in vitro fertilization (IVF) of porcine oocytes.
Methods:  The IVM and IVF media were modified North Carolina State University-37 solution and modified Tyrode's albumin lactate pyruvate, respectively. Porcine oocytes were matured in IVM medium containing 75–2400 µmol ammonia. Amino acids (1.0 mmol) or their dipeptides (2.0 mmol) related to the urea cycle were added individually to the IVM and IVF media containing 300 µmol ammonia. Oocyte maturation and fertilization were assessed using acetic–orcein staining, and the accumulation of ammonia in the media was measured using the indophenol method.
Results:  Percentages of metaphase II (MII) were adversely affected ( P <  0.05) by ≥300 µmol concentrations of ammonia in the IVM medium. In the presence of 300 µmol ammonia in the IVM and IVF media, glutamic acid, l -alanyl-L-glutamine (AlaGln), l -glycyl-L-glutamine (GlyGln) and AlaGln + GlyGln showed the highest rate ( P <  0.05) of MII, monospermic fertilization, and the lowest rate ( P <  0.05) of ammonia accumulation in the media.
Conclusion:  AlaGln and GlyGln in IVM and IVF media were more stable and effective than the individual amino acids in reducing the accumulation of ammonia, and increased the rate of porcine oocyte MII and monospermic fertilization in vitro . (Reprod Med Biol 2007; 6 : 165–170)     

Effect of dietary (n-3) and (n-6) fatty acids on in vivo pulmonary bacterial clearance by neonatal rabbits.

Intrapulmonary bacterial clearance, lung inflammatory cell recruitment and macrophage superoxide generating capacity were studied in newborn rabbits nursed by their mother and given a supplement of either high [5 g/(kg.d)] or low [0.22 g/(kg.d)] doses of fish oil, safflower oil or saline for 7 d after birth. The high dose fish and safflower oil regimens diminished lung clearance of inspired Staphylococcus aureus by approximately 50% compared with the saline controls, but they did not alter lung neutrophil recruitment or alveolar macrophage bacterial phagocytosis. Only high dose fish oil decreased macrophage superoxide anion generation (by 30%). With high dose fish or safflower oil supplementation, the fatty acid content of lung parenchyma, bronchoalveolar lavage effluent and alveolar macrophages increased significantly. Low dose supplementation did not have this effect. We conclude that pharmacologic dietary (n-6) and (n-3) fatty acid supplementation impairs the ability of the neonatal rabbit lung to kill intrapulmonary S. aureus. It has been proposed that human infant formula be supplemented with fatty acids either to alleviate dietary deficiencies or to treat pulmonary inflammatory disorders. Based on our findings, the effects of such supplementation should be monitored relative to the possible heightened risk of bacterial infection.