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1.
Environmental and socio-cultural variables influencing the distribution of helminth eggs in 608 soil samples were studied in 14 playgrounds that differ in socio-economic status in Kaduna metropolis, Nigeria, using a modified sieving method and a sucrose flotation medium of specific gravity 1.27. Helminth eggs were found in 62% of the soil samples and the distribution was as follows: Toxocara spp. 50.4%, Taenia spp./Echinococcus spp. 36.9%, Dipylidium caninum 26.3%, Ancylostoma spp. 9.0%, Ascaris spp. 7.2%, Trichuris spp. 3.7% and Ascaridia spp. 1.9%. A higher prevalence (68.1%) was recorded during the dry harmattan period while in the rainy period the rate was 58.1%. Mean egg densities ranged from 1.11 +/- 0.32 to 3.92 +/- 2.47 in areas moderately rated. Samples from site 14, which was highly rated, were more contaminated (78.1%) than those collected from other sites, while the intensity of contamination (14.0%) was more in moderately rated site 4 than in the rest of the sites. There were significant associations between the prevalence of helminth eggs and rainy period of the study (odds ratio (OR) = 0.38; 95% confidence interval (CI) on OR: 0.20 0.05). This study shows that the period of study, the presence of dogs and vegetation influence the prevalence of helminth eggs in soil in Kaduna metropolis.  相似文献   
2.
Twenty-one Bunaji (BJ) bulls and 21 Friesian x Bunaji (FRxBJ) crossbred bulls, approximately 6 mo of age were divided after weaning into two groups and fed isocaloric rations (2.40 ME Mcal/Kg/DM) containing crude protein levels of 14.45% (high protein) and 8.51% (low protein) for a period of 16 mo to determine the effect of protein intake on puberty. Animals on high protein diets ejaculated first motile spermatozoa and attained puberty at significantly (P < 0.05) earlier ages than those on low protein diets. Mean ages at puberty in mo for BJ on low and high protein diets were 15.50 +/- 0.51 and 14.82 +/- 0.68 and for FRxBJ, the ages were 17.79 +/- 0.82 and 12.94 +/- 0.60, respectively. The animals on high protein diets at point of puberty had significantly (P < 0.05) lighter body weights, smaller scrotal circumference, lower chest girth, better body condition score and better sperm quality than those on low protein. There were no significant (P > 0.05) differences in withers height or volume of semen at puberty for the two protein diets.  相似文献   
3.
The use of molecular diagnostic tools in epidemiological investigations of Cryptosporidium, Giardia, and Enterocytozoon has provided new insights into their diversity and transmission pathways. In this study, 157 stool specimens from 2-month to 70-year-old patients were collected, a polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) analysis of the small subunit (SSU) rRNA gene was used to detect and differentiate Cryptosporidium species, and DNA sequence analysis of the 60 kDa glycoprotein (gp60) gene was used to subtype Cryptosporidium hominis and Cryptosporidium parvum. Giardia duodenalis, and Enterocytozoon bieneusi in the specimens were detected using PCR and sequence analysis of the triosephosphate isomerase (tpi) gene and internal transcribed spacer (ITS), respectively. C. hominis and C. parvum were found in two (1.3%) and one (0.6%) specimen respectively, comprising of Ia and IIe (with 8 nucleotide substitutions) subtype families. The G. duodenalis A2 subtype was detected in five (3.2%) specimens, while four genotypes of E. bieneusi, namely A, type IV, D and WL7 were found in 10 (6.4%) specimens. Children aged two years or younger had the highest occurrence of Cryptosporidium (4.4%) and Enterocytozoon (13.0%) while children of 6 to 17 years had the highest Giardia infection rate (40.0%). No Cryptosporidium, Giardia, and Enterocytozoon were detected in patients older than 60 years. Enterocytozoon had high infection rates in both HIV-positive (3.3%) and HIV-negative (8.3%) patients. Results of the study suggest that anthroponotic transmission may be important in the transmission of Cryptosporidium spp. and G. duodenalis while zoonotic transmissions may also play a role in the transmission of E. bieneusi in humans in Kaduna State, Nigeria.  相似文献   
4.
Catechol 2, 3-dioxygenase is present in several types of bacteria and undergoes degradation of environmental pollutants through an important key biochemical pathways. Specifically, this enzyme cleaves aromatic rings of several environmental pollutants such as toluene, xylene, naphthalene and biphenyl derivatives. Hence, the importance of Catechol 2, 3-dioxygenase and its role in the degradation of environmental pollutants made us to predict the three-dimensional structure of Catechol 2, 3-dioxygenase from Burkholderia cepacia. The 10ns molecular dynamics simulation was carried out to check the stability of the modeled Catechol 2, 3- dioxygenase. The results show that the model was energetically stable, and it attains their equilibrium within 2000 ps of production MD run. The docking of various petroleum hydrocarbons into the Catechol 2,3-dioxygenase reveals that the benzene, O-xylene, Toluene, Fluorene, Naphthalene, Carbazol, Pyrene, Dibenzothiophene, Anthracene, Phenanthrene, Biphenyl makes strong hydrogen bond and Van der waals interaction with the active site residues of H150, L152, W198, H206, H220, H252, I254, T255, Y261, E271, L276 and F309. Free energy of binding and estimated inhibition constant of these compounds demonstrates that they are energetically stable in their binding cavity. Chrysene shows positive energy of binding in the active site atom of Fe. Except Pyrene all the substrates made close contact with Fe atom by the distance ranges from 1.67 to 2.43 Å. In addition to that, the above mentioned substrate except pyrene all other made π-π stacking interaction with H252 by the distance ranges from 3.40 to 3.90 Å. All these docking results reveal that, except Chrysene all other substrate has good free energy of binding to hold enough in the active site and makes strong VdW interaction with Catechol-2,3-dioxygenase. These results suggest that, the enzyme is capable of catalyzing the above-mentioned substrate.  相似文献   
5.
Effect of alcohol-kolanut interaction on Sodium Pump activity in wistar albino rats was studied. Thirty wistar albino rats were divided into six groups of five (5) rats per group and used for the study. The control group (1) received via oral route a placebo (4ml of distilled water). Groups 2 to 6 were treated for a period of 21 days, with (10% v/v) of alcohol (group 2), 50mg/kg body weight of kolanut (group 3), 50 mg/kg body weight of caffeine (group 4), 4ml of 10% v/v of alcohol and 50 mg/kg body weight kolanut (group 5), 4ml of 10% v/v of alcohol and 50 mg/kg body weight of caffeine in 4.0ml of the vehicle via gastric intubation respectively. A day after the final exposure, the brain of each rat was harvested and processed to examine several biochemical parameters, i.e., total ATpase, ouabain-insensitive ATpase, ouabain sensitive ATpase (Na(+)-K(+)ATPase), non-enzymatic breakdown of ATP and inorganic phosphate (Pi) released. The results showed that the essential enzyme of the brain responsible for neuronal function, Na(+)-K(+)ATPase, was inhibited by alcohol-kolanut co-administration relative to control, resulting in a decrease in Na(+)-K(+)ATPase activity, ATP production, ion transport and action potential, leading to loss of neuronal activities.  相似文献   
6.
The atherogenic potentials of peeled grated cocoyam (Xanthosoma maffafa scot) "ekpang nkukwo", pounded yam (Discorea spp) with plain soup "afia efere", and plantain porridge (Musa paradisiaca) "iwuk ukom" meals were investigated. The three meals were fed to three different groups of albino rats of Wistar strain for a period of twenty eight days. A fourth group which served as control was feed with normal rat pellet. The mean total plasma cholesterol level in the pounded yam with plain soup fed group was significantly lower [P < 0.05] when compared to the control and peeled grated cocoyam fed groups. The mean total plasma triglyceride (MTPTG) level in the pounded yam with plain soup fed group was significantly lower [P < 0.05] when compared to the control group. However the MTPTG level in the peeled grated cocoyam and plantain porridge fed groups were comparable to control. The mean HDL-cholesterol level in the peeled grated cocoyam and plantain fed groups were comparable control. The mean LDL-cholesterol level in the peeled grated cocoyam and plantain porridge fed groups was significantly lower [P < 0.05] than the control group. The LDL-cholesterol and VLDL-cholesterol in the pounded yam with plain soup fed group was significantly lower [P < 0.05] when compared to control. These findings suggest low atherogenic potentials of the pounded yam with plain soup meal compared to the peeled grated cocoyam and plantain porridge meals.  相似文献   
7.
Even though the liver synthesizes most of circulating IGF-1, it lacks its receptor under physiological conditions. However, according to previous studies, a damaged liver expresses the receptor. For this reason, herein, we examine hepatic histology and expression of genes encoding proteins of the cytoskeleton, extracellular matrix, and cell-cell molecules and inflammation-related proteins. A partial IGF-1 deficiency murine model was used to investigate IGF-1’s effects on liver by comparing wild-type controls, heterozygous igf1+/?, and heterozygous mice treated with IGF-1 for 10 days. Histology, microarray for mRNA gene expression, RT-qPCR, and lipid peroxidation were assessed. Microarray analyses revealed significant underexpression of igf1 in heterozygous mice compared to control mice, restoring normal liver expression after treatment, which then normalized its circulating levels. IGF-1 receptor mRNA was overexpressed in Hz mice liver, while treated mice displayed a similar expression to that of the controls. Heterozygous mice showed overexpression of several genes encoding proteins related to inflammatory and acute-phase proteins and underexpression or overexpression of genes which coded for extracellular matrix, cytoskeleton, and cell junction components. Histology revealed an altered hepatic architecture. In addition, liver oxidative damage was found increased in the heterozygous group. The mere IGF-1 partial deficiency is associated with relevant alterations of the hepatic architecture and expression of genes involved in cytoskeleton, hepatocyte polarity, cell junctions, and extracellular matrix proteins. Moreover, it induces hepatic expression of the IGF-1 receptor and elevated acute-phase and inflammation mediators, which all resulted in liver oxidative damage.  相似文献   
8.
We present information on the prey taken by the Bat Hawk Macheiramphus alcinus in two different areas of lowland western central Madagascar. These are the first dietary data from Madagascar for this widespread Old World species. The recovered remains were almost exclusively of bats and birds, with a few examples of reptiles and insects. In total, 178 pellets were analysed. On the basis of minimum number of individuals and biomass, bats accounted for 58.3% and 30.3%, respectively, and birds 36.1% and 69.7%, respectively. Amongst the nine species of bats recovered from the pellets, four were represented by multiple individuals, particularly taxa belonging to the families Molossidae and Vespertilionidae that fly in open areas, and for the 11 species of identified birds, all were represented by a single individual. These patterns are interpreted as a specialisation of feeding on bats during a narrow window of time at dusk, as they leave day roost sites, and then using birds in a more general manner to fill in nutritional needs.  相似文献   
9.
Reduced meat intake is often associated with iron deficiency anaemia. Reduced meat intake that arose from the frugality associated with a prolonged period of national economic reorientation policy, known as the "structural adjustment programme" (SAP), may have placed iron-stress on pregnancy in particular. Iron status of pre-SAP and SAP pregnancies were established from measurement of the haematological values of subjects. Indices such as haemoglobin (Hb), packed cell volume, serum Fe were lower in pregnancy especially during SAP. However, SAP pregnancy serum ferritin did not respond significantly to iron depletion. Unlike PCV, Total Iron Binding Capacity (TIBC) and serum transferrin values showed a reverse behaviour. The level of these values, however, portends a toll exerted on body iron status in pregnancy associated with reduced haem iron intake. The changes in these values did not, however, lead to any over symptoms of iron deficiency probably because increased sea food (molluscs) consumption ameliorates the iron-toll from low absorbed non-haem iron. For lower income rural women in non-coastal areas, the absence of seafood in their diets exacerbates the low iron status in Pregnancy.  相似文献   
10.
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