Supplementation of vitamin A to local chicken diets in tropical environment enhances seminal quality and blood testosterone concentration.

There is insufficient information on the role of micronutrient supplementation on the productivity of local breeder cocks in a tropical environment. The target of this research, thus, was to deduce the impact of dietary vitamin A incorporation on semen traits and testosterone concentration of local breeder cocks in a tropical environment. One hundred twenty-eight-matured Nigerian local breeder cocks aged 10-12 months were alloted to 4 groups (n = 32): a control group (A) was fed experimental diet supplemented with vitamin A at 0 IU/kg feed and supplemented groups (B-D) fed commercial poultry diet supplemented with vitamin A at 250, 500 and 750 IU/kg feed for 16 weeks. Every group was replicated 4 times with 16 birds in every a replicate. A quadratic typed optimization function was employed to determine the optimum vitamin A supplementation that statistically improved serum testosterone and semen quality indices in local breeder cocks. Semen profiling and serum testosterone concentration were analysed at week 4 (pre-supplementation period), and thereafter at weeks 4, 8 and 12 (supplementation period). Serum testosterone and semen quality indices at pre-supplementation period were similar (p < 0.05) among the groups. Birds on 500 IU vitamin A/kg diet produced sperm with highest (p < 0.05) active motile cells and normal morphology compared to birds on the other 3 diets. Local breeder cocks fed diets having 500 and 750 IU vitamin A/kg diet produced sperm with lowest (p < 0.05) sluggish motile cells compared with those fed the control diet. Semen pH, volume, sperm concentration (SC), acrosome morphology defects and serum testosterone concentration were not affected by vitamin A supplementation. The result of the quadratic optimization model revealed that sluggish motile sperm (Y = 41.098-10.230x + 0.903x2; r2 = 0.943, p = 0.039) and normal sperm morphology (Y = 82.665 + 8.834x - 1.500x2; r2 = 0.965, p = 0.001) was optimized (p < 0.05) at 5664 and 2945 IU/kg feed, respectively. However, other parameters estimated were not significantly influenced. It is concluded that vitamin A supplementation enhanced sperm quality in local breeder cocks.

Genetic diversity and distribution of Mycobacterium tuberculosis genotypes in Limpopo, South Africa.

BACKGROUND: Tuberculosis remains a major health problem and knowledge of the diversity of Mycobacterium tuberculosis strains in specific geographical regions can contribute to the control of the disease. This study describes the genetic profile of M. tuberculosis in five districts of Limpopo Province. METHODS: A total 487 isolates were collected from the National Health Laboratory Services from all regions/districts of Limpopo Province. Only 215 isolates were confirmed to be M. tuberculosis by Bactec Mycobacterium Growth Indicator Tube 960® and Rhodamine-Auramine staining. Isolates were subcultured on Löwenstein-Jensen medium agar slants to validate purity. They were spoligotyped and data analysed using the international spoligotyping database 4 (SpolDB4). RESULTS: Of the 215 isolates, 134 (62.3%) were genotyped into 21 genotype families while 81 (37.7%) were orphans. The 81 orphans were further subjected to resolution employing SpolDB3/RIM. Overall, the study revealed a high diversity of strains of 32 predominantly the non-Beijing lineages: the LAM- LAM3 (9.8%), LAM9 (4.7%) and LAM11- ZWE (3.3%), the T-T1(15.0%), T2 (0.9%), T2-T3 (1.4%), the CAS-CAS1-Delhi 5 (1.9%) and CAS1-KILI (1.4%) the MANU2 (1.4%), U (0.5%), X-X1(1.4%), X3 (1.9%), S (9.8%), CAS (1.4%), LAM7(0.9%), T3(0.5%), LAM8(4.7%), T4(1.4%), X2(0.4%), AI5(1.9%), LAM1(0.5%), FAMILY33 (1.9%), EAI4(1.4%), M. microti (1.9%). The Beijing and Beijing-like families were (14.9%) and (0.9%), respectively. A total of 28(13%) clusters and 77(36%) unique cases were identified. Beijing strain (SIT 1) formed the biggest cluster constituting 14%, followed by LAM3 (SIT 33), T1 (SIT 53) and LAM4 (SIT 811) with 7%, 5.1% and 2.8%, respectively. The Beijing family was the only genotype found in all the five districts and was predominant in Mopani (18.8%), Sekhukhune (23.7%) and Vhembe (23.3%). Dominant genotypes in Capricorn and Waterberg were LAM3 (11.9%) and T1 (13.3%), respectively. CONCLUSION: A wide diversity of lineages was demonstrated at district level. A high number of clusters per district provided evidence of on-going transmission in this Province.

In vitro investigation of clofazimine analogues for antiplasmodial, cytotoxic and pro-oxidative activities.

BACKGROUND: Tetramethyl-piperidine-substituted, B4119 and B4158 have been shown to exhibit antiplasmodial activity. OBJECTIVES: The in vitro antiplasmodial, cytotoxic and oxidative activities of clofazimine and its analogues, all TMP (tetramethylpiperidyl)-substituted phenazines except B669, were evaluated in this study. METHODS: The antiplasmodial activity of the compounds against RB-1 and pfUP10 laboratory strains of Plasmodium falciparum was investigated by flow cytometry. The cytotoxic activity against HeLa cells and oxidative activity were studied employing colorimetric and cytochrome C reduction assays respectively. RESULTS: The riminophenazine agents exhibited antiplasmodial action of varying degrees: B669, B4100 and B4103 showed the best activity while B4121 and B4169 exhibited significant activity at 2µg/ml. Clofazimine had no antiplasmodial activity. The compounds B4100, B4103, B4121 and B4169 exhibited significant cytotoxic activity against HeLa cells at concentrations of 0.5µg/ml and above while B669 was active at 2µg/ml. Clofazimine and B669 tested at a concentration of 0.5µg/ml caused enhancement (p ≤ 0.05) of neutrophil superoxide production when compared to the FMLP control while all the other TMP-derivatives had no effect (p ≥ 0.05). CONCLUSION: Tetramethylpiperidyl-subsituted phenazines may potentially be useful antimalarial/antitumor agents with no pro-oxidative properties. In vivo studies on the agents relative to these properties are recommended.

Growth and haematological response of indigenous Venda chickens aged 8 to 13 weeks to varying dietary lysine to energy ratios.

The effect of feeding varying dietary lysine to energy levels on growth and haematological values of indigenous Venda chickens aged 8 - 13 weeks was evaluated. Four hundred and twenty Venda chickens (BW 362 ± 10 g) were allocated to four dietary treatments in a completely randomized design. Each treatment was replicated seven times, and each replicate had fifteen chickens. Four maize-soya beans-based diets were formulated. Each diet had similar CP (150 g/kg DM) and lysine (8 g lysine/kg DM) but varying energy levels (11, 12, 13 and 14 MJ ME/kg DM). The birds were reared in a deep litter house; feed and water were provided ad libitum. Data on growth and haematological values were collected and analysed using one-way analysis of variance. Duncan's test for multiple comparisons was used to test the significant difference between treatment means (p < 0.05). A quadratic equation was used to determine dietary lysine to energy ratios for optimum parameters which were significant difference. Results showed that dietary energy level influenced (p < 0.05) feed intake, feed conversion ratio, live weight, haemoglobin and pack cell volume values of chickens. Dry matter digestibility, metabolizable energy and nitrogen retention not influenced by dietary lysine to energy ratio. Also, white blood cell, red blood cell, mean corpuscular volume, mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration in female Venda chickens aged 91 days were not influenced by dietary lysine to energy ratio. It is concluded that dietary lysine to energy ratios of 0.672, 0.646, 0.639 and 0.649 optimized feed intake, growth rate, FCR and live weight in indigenous female Venda chickens fed diets containing 8 g of lysine/kg DM, 150 g of CP/kg DM and 11 MJ of ME/kg DM. This has implications in diet formulation for indigenous female Venda chickens.

The mandibular angles of dry adult human mandibles from north eastern arid zone of Nigeria.

OBJECTIVES: To study and document the mandibular angle of Nigerians from the north eastern arid zone, and investigate its role as an anthropological parameter for racial and or population groups differential diagnosis, its utilization in laryngoscopy and for successful inferior alveolar nerve anesthesia. DESIGN: A cross sectional study. SETTING: Department of Anatomy, College of Medical Sciences, University of Maiduguri, Maiduguri, Borno State, Nigeria. SUBJECTS: 60 dry adult mandibles from Nigerians who lived in Maiduguri (Borno State Capital) and its environ until their death. MAIN OUTCOME MEASURES: Measurements of the right and left mandibular angles, length and height of the mandibles and the comparison of the mean angle with that of other racial and or population groups. RESULTS: The mean mandibular angle (118.75 +/- 0.395 i.e. mean +/- SEM) was smaller than that of other African populations but was wider than that of the Neanderthals and similar to that of the Chinese and Peruvians. The mandible had a shorter ramus, slightly longer length resulting in a smaller angle than that of the Zimbabwean mandible. Highly significant differences occurred between the mean angle of the Nigerian mandible and those of other African population groups (p < 0.0001) except the mandibular angle of Natal Nguni and Cape Nguni populations from South Africa. There was no mutual dependence and no significant departure from linearity between the mean angle, length and height. CONCLUSION: The mandibular angle in conjunction with other anthropological parameters may be useful anthropological tools in racial and or population diagnosis. The configuration of the mandible of Nigerians from the northeast arid zone may predispose them to difficult laryngoscopy and/or intubation.

Bony anomalies of the craniocervical junction.

A review of the literature on bony anomalies of the craniovertebral junction was carried out with emphasis on anomalous manifestations associated with the occipital bone, atlas and axis vertebrae. A summary of the evolution and normal development of the above bony structures and the embryological structures contributing to the bony anomalies is presented. In addition the diagnostic measurements used for the diagnosis of the bony anomalies of the craniocervical junction and their clinical presentation were summarised. This review was prepared with the aim of providing reference material for neurosurgeons and radiologists.

A study of the position of the mandibular foramen in adult black Zimbabwean mandibles.

OBJECTIVES: To determine the position of the mandibular foramen on dry adult mandibles and hence provide valuable information for dental and other health practitioners for successful inferior alveolar nerve anaesthesia. DESIGN: A cross sectional study. SETTING: Department of Anatomy, Faculty of Medicine, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe. SUBJECTS: 38 dry mandibles from adult black Zimbabweans. MAIN OUTCOME MEASURES: The anterior and posterior rameal widths, upper and lower rameal heights and the height of the lingula were measured with respect to the position of the mandibular foramen. The distribution of the foramen in relation to the occlusal plane was determined. RESULTS: The results showed that the position of the mandibular foramen was highly individualistic but on average lies at about 2.56 mm (right) and 2.08 mm (left) behind the midpoint of rameal width and at approximately 3 mm superior to the midpoint of rameal height on both sides. The mean anterior and posterior rameal widths were respectively 18.95 +/- 0.41 and 14.30 +/- 0.35 while the mean rameal heights were respectively 22.50 +/- 0.50 (upper) and 28.44 +/- 0.65 (lower). The distribution of the foramen in relation to the occlusal plane was 47.1% at the same level with the occlusal plane, 29.4% above, and 23.5% below the plane. There was no side variation in the position of the foramen in relation to the occlusal plane, in the dimensions of the ramus and in the size of the mandibular foramen but individual variations exist. The height of the lingula however showed great variation. The mean height was 8.40 +/- 0.39 (right) and 8.36 +/- 0.38 (left). CONCLUSION: The study has shown similarities and differences between the rameal dimensions and the position of the mandibular foramen in adult black Zimbabwean mandibles and those of other subpopulations. The clinical significance of accurately locating the mandibular foramen during a local anesthetic block of the inferior alveolar nerve is discussed.

Hypotensive effect of crude extract Olea. africana (Oleaceae) in normo and hypertensive rats.

OBJECTIVE: To investigate the effects of crude extracts of the root and stem of Olea africana on mean arterial pressure (MAP) and heart rate in normo and hypertensive rats. DESIGN: Comparative study. SETTING: Laboratory. SUBJECTS: 40 Sprague Dawley rats of either sex (150 to 250 g) randomly assigned to normotensive (n = 15) (DOCA) -salt hypertensive (n = 25) groups. The normotensive group comprised three subgroups (n = 5) namely, a control treated with graded volumes of normal saline intravenously (i.v.), and two groups respectively treated with graded doses of aqueous extract of O. africana (i.v.). The hypertensive group comprised five subgroups (n = 5) namely, a control group of sham operated rats, and four groups of nephrectomised rats. One group of nephrectomized rats received Deoxycorticosterone acetate (DOCA) and salt for seven days, while others received DOCAsalt for 14 days. Two groups of the 14 day treated rats respectively received 200 mg/kg and 1,000 mg/kg of O. africana orally thereafter. MAP and HR were measured under sodium pentobarbital anaesthesia (35 mg/kg intraperitoneally). MAIN OUTCOME MEASURES: Mean arterial pressure and heart rate. RESULTS: Intravenous administration of aqueous and ethanolic extracts of O. africana caused an immediate and dose dependent fall in MAP and HR in anaesthetised normotensive rats. The aqueous extract was more potent than the ethanolic extract. Orally administered aqueous extract produced lowering of MAP and HR in DOCA-salt hypertensive rats. Propranolol partially blocked the Map lowering effect of O. africana. CONCLUSION: Extracts of O. africana lowered MAP and HR in normotensive and DOCA-salt hypertensive rats. Hence the use of the aqueous extracts in the treatment of some forms of hypertension and heart palpitations in humans. This effect may be mediated via beta adrenergic receptors.

Position of the mental foramen in adult black Zimbabwean mandibles: a clinical anatomical study.

OBJECTIVE: To provide some anatomical information on the shape, size, and position of the mental foramen among Black Zimbabweans that could be used as reference material by dental and other health practitioners during clinical practice in Zimbabwe. DESIGN: Cross sectional anatomical study. SETTING: Department of Anatomy, Faculty of Medicine, University of Zimbabwe, Mount Pleasant, Harare, Zimbabwe. SUBJECTS: 32 mandibles derived from adult Black Zimbabweans. MAIN OUTCOME MEASURES: The shape of the mental foramen, its relation to the lower teeth and its position in relation to the mandibular symphysis, the posterior border of the ramus of the mandible, the lower border of the mandible, and the alveolar margin. RESULTS: The shape of the mental foramen was round in 14 out of 32 mandibles (43.8%) and was oval in the remaining 18 (56.3%). The percentage of occurrence of the mental foramen was highest below the lower second premolar tooth on the right side (position 4) and posterior to it on the left side (position 5). In the vertical plane, the mental foramen lay slightly below the midpoint of the distance between the lower border of the mandible and the alveolar margin (44.1% and 45.5% for the right and left sides respectively). In the horizontal plane, it lay approximately one quarter (27.3% for the right and 27.4% for the left sides) of the distance from the mandibular symphysis to the posterior border of the ramus of the mandible. CONCLUSION: The percentage distribution of the mental foremen in relation to the lower teeth in the adult Black Zimbabwean mandible was at variance with that of other population groups. However, the quantitative position of the mental foremen was bilaterally symmetrical in the adult Black Zimbabwean mandible. The latter observation is of clinical significance to dental and other health practitioners in Zimbabwe with regards to the achievement of effective mental nerve block anaesthesia and the prevention of damage to the mental nerve during surgical procedures on the lower jaw.

A preliminary study of stress levels among first year medical students at the University of Zimbabwe.

OBJECTIVE: To assess stress levels among first year medical students at the University of Zimbabwe. DESIGN: A cross sectional study using two questionnaires. SETTING: Department of Anatomy, Faculty of Medicine, University of Zimbabwe, Mount Pleasant, harare, Zimbabwe. SUBJECTS: First year medical students aged between 18 and 24 years who have spent about seven months in the medical school. RESULTS: A total of 109 out of 123 first year medical students were used in the study. The two questionnaires produced similar results with an average of about 35.5% normal and an average of 64.5% of the students being at various levels of stress and or depression. About 11% reported very high levels of stress while the majority of the stressed students fell within the middle bracket. The number of affected students decreased as the level of stress and depression increased and demonstrates the differences in the stress threshold of the individual students. Estimation of suicide tendencies from both questionnaires showed that about 12% of the students were at serious risk and about 20% at lesser risk of psychological and emotional depression. The stratification of group 2 of SRQ-20 was valuable in isolating those students seriously stressed and/or depressed. CONCLUSION: This study has demonstrated that a number of first year medical students of the University of Zimbabwe were at various levels of stress and/or depression. Those students in the extreme stress or depression group need serious attention. This state of psychological and emotional distress in the subsequent years of medical training and during the professional years may lead to serious social consequences. A system of identifying students with low stress threshold early in their training is recommended as well as a means of helping them to deal with the stress and its causes.