A disc-based quantitative carrier test method to assess the virucidal activity of chemical germicides

Suspension tests for virucidal activity of chemical germicides are easier to perform, but they normally do not present the test product with a strong enough challenge. In contrast, carrier tests, where the test virus is dried on an animate or inanimate surface, offer the test formulation a higher level of challenge because it first has to penetrate successfully the inoculum to gain access to and inactivate the target organism on the carrier. Since pathogens in nature are normally found adsorbed to surfaces and/or embedded in organic or cellular debris, the results of carrier tests are more relevant to predicting the activity of chemical germicides under field situations. The method described below uses discs (1 cm in diameter) of brushed stainless steel discs as carriers. Ten micro l of the test virus in a soil load is placed on each disc and the inoculum dried under ambient conditions. The dried inoculum is then exposed to 50 micro l of the test formulation or a control solution for a defined contact time at the specified temperature. EBSS (0.95 ml) is added to each carrier holder to dilute/neutralize the germicide, the inoculum eluted and the eluates titrated in cell cultures to determine the degree of loss in virus viability. At least five test and three control carriers are used in each test. Controls are also included to test for toxicity of the test formulation to the host cells and any interference sub-cytotoxic levels of the formulation may have on the ability of the virus to infect the cells. The method has been used with several types of human and animal pathogenic viruses to test the activity of all major classes of chemical germicides against them.     

Induction and specificity of syngeneic antiserum against rauscher murine leukemia virus-induced leukemia,RBL-5

Plasma membranes purified from RBL-5 leukemia cells and solubilized with Na deoxycholate were fractionated on an Ultrogel AcA34 column. Fractions containing most of the tumor-rejection activity but low amounts of gp70 and p30 were consolidated and used to hyperimmunize semisyngeneic, CBF₁, hybrid mice. Using the complement-dependent cytotoxicity assay, we determined the antibody titers against RBL-5 and several other leukemic cells. Only RBL-5 and EL-4 tumor cells were lysed. Similar results were obtained when the same tumor cells were used to absorb the syngeneic antiserum and the residual cytotoxic titer determined on RBL-5 target cells. Coupling of the gamma-globulins from this antiserum to Sepharose 4B facilitated the isolation of an antigen which inhibited the C'-dependent lysis of RBL-5 tumor cells and, when used for immunization, protected the recipient mice against a subcutaneous challenge of RBL-5 leukemia cells. By means of discgel electrophoresis, in the presence of SDS and 2-mer-captoethanol, two polypeptide chains with molecular weights of 46,000 and 21,000 were resolved. The binding of the antigen to a lens culinaris lentil lectin column and its subsequent elution with α-methyl mannoside suggests that the specific tumor antigen is a glycoprotein.     

Interaction between ciprofloxacin and chloroquine in mice infected with chloroquine resistant Plasmodium berghei: interaction between ciprofloxacin and chloroqune

The increasing spread of chloroquine resistant malaria has intensified the search for new antimalarial treatment, especially drugs that can be used in combination. Ciprofloxacin (CFX) a fluoroquinolone commonly used to treat bacterial infections has been shown to possess significant antimalarial activity both in vitro and in vivo. Thus efforts in this study were devoted to evaluating the antimalarial activity of combination of chloroquine (CQ) with varying doses (10, 20, 40 80, 160 mg/kg body weight) of CFX in groups of 35 mice inoculated intraperitoneally with 10⁷ chloroquine resistant strain Plasmodium berghei ANKA. Parasitological activity and survival of the animals were assessed over 21 days. Parasitemia in non-treated control mice peaked at 78% on day 9 and none survived by day 10. However, the combination of CQ with 160 mg/kg body weight of CFX resulted in a reduction in parasitemia between days 9 and 14 and this was significantly lower than that obtained with CQ alone or CQ combined with the lower doses of CFX (p < 0.05). In addition, the combination of CQ with 160 mg/kg CFX significantly reduced mortality in the infected animals (p = 0.0002) compared with the other treatment groups. The results from this study support the potential usefulness of CFX in combination with antimalarial drugs for the treatment of chloroquine resistant human malaria.     

Anthropometric parameter that best predict metabolic syndrome in South west Nigeria

AimThis study compared the ability of anthropometric parameters to predict Metabolic Syndrome (MetS).MethodsEleven anthropometric parameters: waist circumference (WC), body mass index (BMI), waist-to-height ratio (WHtR), a body shape index (ABSI), body roundness index (BRI), visceral adiposity index (VAI), abdominal volume index (AVI), Conicity Index (CI), body adiposity index (BAI), lipid accumulation product (LAP) and waist circumference-triglyceride index (WTI) were measured and calculated in apparently healthy subjects with and without MetS. A receiver operating characteristic (ROC) curve was applied to assess their ability to predict MetS.ResultsOf the 535 subjects recruited 23% had MetS. WC had the largest area under the curve (AUC) in both men (0.814 95% CI 0.721–0.907) and women (0.819 95%CI 0.771–0.867). This did not differ from the AUC of BMI, WHtR, BRI, CI, BAI, LAP in men and BMI, WHtR, BAI, LAP, VAI and WTI in women (P > 0.05). The cutoff point for WC was 89.5 cm and 91.8 cm in men and women respectively. The AUC of WC was the largest in the 40–49 and 60 years and above age groups while the AUC of LAP was the largest for age groups 30–39 and 50–59 years.ConclusionOf the 11 anthropometric parameters assessed, the WC was the best at predicting MetS in both men and women. There is need to ascertain the cutoff point and establish landmark for measuring WC especially for the sub Saharan region.     

In vitro effects of 2-methyl-3-propylbutane-1,4-diol purified from Alstonia boonei on erythrocyte membrane stabilization and mitochondrial membrane permeabilization

A recent review on the ethnomedicinal, chemical, pharmacological, and toxicological properties of Alstonia boonei revealed the plant's potential in the treatment and management of a range of diseases. However, most of these pharmacological effects are only traceable to the crude form of the plant extract and not specific natural products. Phytochemical investigation of the methanol fraction of the methanol extract of the stem-bark of Alstonia boonei led to the isolation and identification of 2-methyl-3-propylbutane-1,4-diol. The structures were elucidated by the application of 1D-, and 2D-NMR spectroscopic analyses and by comparison with literature data. In this study, the membrane stabilizing activity, mitochondrial membrane permeability transition pore opening, cytochrome c release, mitochondrial ATPase activity, and prevention of mitochondrial lipid peroxidation activity of 2-methyl-3-propylbutane-1,4-diol (MPBD) isolated from A. boonei were determined. The results showed that MPBD significantly (p < .05) prevented peroxidation of mitochondrial membrane lipids and hemolysis using both the heat-induced and hypotonic solution-induced membrane stabilization assays. On the contrary, the compound caused large amplitude swelling of rat liver mitochondria in the absence of calcium, significant (p < .05) cytochrome c release and enhancement of mitochondrial ATPase activity in vitro. Our findings suggest that MPBD showed characteristic biological properties useful in modulating cell death.