The relationship between basal blood pressure and body mass index in apparently healthy Nigerian adolescent students

Background: In contrast to the situation in developed countries, very few studies have been done on blood pressure (BP) determinants among Nigerian adolescents.   Aim: To evaluate the relationship between basal BP and body mass index (BMI) in a group of healthy Nigerian secondary school students. Methods: This was a cross-sectional study of 1080 adolescent students selected by a two-stage multi-phase cluster sampling technique. The height, weight and BP of each student were taken using standard methods. Pearson correlation was used to describe the strength of association between variables.  Multiple stepwise regressions were conducted to determine the individual or combined contribution(s) of some variables to the variation in BP levels. Results: Mean BMI for males and females were 17.63 ± 2.54 kg/m2 and 18.87 ± 1.81 kg/m2 respectively. Forty six students (4.3%) were overweight. Mean systolic and diastolic BPs were 113.13 + 11.44 mm Hg and 68.29 + 8.07 mm Hg respectively. Thirty-five subjects (3.2%) had systolic or diastolic BP above the 95th percentile for age and sex.  Twenty-four (68.6%) of these subjects were also found to be overweight.  A moderate positive correlation was observed between both systolic and diastolic BP and BMI. Regression analysis showed that weight, height and BMI were predictors of systolic BP.  Height and BMI were the only predictors of diastolic BP.  Conclusion: These findings suggest that there is a moderate association between basal BP and BMI.  Recommendation:  Control/prevention of the accumulation of excess body fat in adolescence is recommended.   Keywords: Body mass index, Blood pressure, Adolescent, Nigerian

Toxicological evaluation of the stem bark of Burkea africana hook. (Caesalpiniaceae) in wistar rats

Burkea africana Hook. (Caesalpiniaceae) is used traditionally to treat ulcers, headaches, skin disease and tumors. The study investigated the acute, sub-acute and chronic toxicity profiles of the ethanolic extract of Burkea africana stem bark. Rats of either sexes were used in this study (n=10). For  acute toxicity, a single dose of 5,000 mg/kg was administered while for the sub-acute and chronic toxicity study, three doses (40, 200 and 1000  mg/kg) of the extract were administered orally for 28 and 90 days respectively. At the end of each study, the biochemical, hematological and  histological parameters were evaluated. No mortality or behavioral changes were observed in the acute toxicity study. Extract caused significant  changes in the hematological parameters after the sub-acute toxicity study. In the chronic toxicity study, the extract caused significant increase in  the white blood cell count of the 200 mg/kg group. There was significant increase in the platelet count of treated groups compared to control in the sub-acute and chronic toxicity studies, with an observed total mortality of all the animals in the 1000 mg/kg group on the 44th day. No adverse pathology was observed in the organs examined. The extract elicited a hematological response and short term consumption of the extract at low doses might be relatively safe. However, long term consumption at high doses should be discouraged

Effect of Temperature on Drying Characteristics and Quality of Three Nigerian Onion Varieties Using a Fabricated Electrically Powered Dryer

The research work is done to evaluate the effect of temperature on drying characteristics and quality of red, cream and white varieties Nigerian onion using a locally fabricated electrically powered dryer. Clean onion samples of 1.5 kg from each of the three varieties were sliced into 3 mm thickness. Fresh samples of the three onion varieties were analyzed to determine the initial values of protein, fat, ash, crude fibre, and moisture content on a dried basis (m.c.d.b.) using recommended AOAC methods.. Vitamin C and microbial loads content were determined before loading into a locally fabricated electrically-powered dryer. The onion samples were dried at varying pre-determined temperatures of 50, 60, and 70 oC. After drying, the proximate compositions, vitamin C and microbial loads were also determined. The protein, fat, ash and crude fibre of the fresh onion samples were 1.5, 0.5, 0.6 and 0.5%, respectively, while m.c.d.b, vitamin C content and microbial loads ranged from 85.1-88.2%, 8.1-8.3 mg/100 gm and 4.45-5.39 mg. Red onion samples were dried for 13:15h, 12:10h and 10:30h; white onion samples for 13:00h, 12:25h and 10:40h; while cream onion samples for 13:10h, 12:35h and 10:15h at 50, 60, and 70 oC, respectively. The protein, fat, ash, crude fibre, m.c.d.b, vitamin C content and microbial loads of the dried onion samples at all the drying temperatures ranged from 10.110.4, 1.1-1.5, 3.3-3.5, 5.5-5.8, 5.5-6.9%, 3.1-4.9 mg/100 gm, 1.314.17 mg, respectively. The drying temperature had a significant effect (p-value < 0.05) on the quality of all the onion samples. At 70 oC, protein, fibre, ash, fat and pungency retention were significantly (p< 0.05) high and within acceptable limits while microbial loads were low with the reduction in Vitamin C contents in all the onion varieties. Therefore, onion can best be dried at 70 oC to achieve the optimum quality and flavour required for its use as a spice