133 research outputs found
Evaluation of Physical and Mechanical Properties of Selected Wood Species obtained from Saw Mills in Akure, Nigeria
The strength and sorption properties of selected wood species obtained from saw mills in Akure Nigeria were investigated based on key index properties such as density, bending strength and dimensional stability using appropriate standard experimental techniques. Data obtained from the experimental investigation revealed that the wood species ranged from low density 442.8 kg/m3 for Terminalia superba (Afara), through medium density 464 kg/m3 and 552.8 kg/m3 for Pycnanthus angolensis (Akomu) and Gmelina arborea (Gmelina) respectively, to high density 635.7kg/m3 and 678.2 kg/m3 for Milicia excelsa (Iroko) and Stereospermum acuminatissimum (Omo cedar) respectively. The bending strength values obtained qualified the wood species classification into low bending strength (25 N/mm2 – 75 N/mm2 ) for Afara, Akomu and Gmelina and the medium static bending strength in the range (75 N/mm2 – 125 N/mm2) for Iroko and Omo cedar. Furthermore, results of volumetric shrinkage and swelling are 7.21%: 5.04%, 7.75%: 5.26% and 7.84%: 6.69% for Afara, Akomu and Gmelina respectively while Iroko and Omo cedar recorded 10.95%: 7.84% and 11.08%: 11.08%. These updated results could be useful for wood selection for building construction application; for structural members in roofing, posts and beams
HEAVY METALS IN THE MYONEMATIC, HEPATIC AND RENAL TISSUES OF THE AFRICAN CAT FISH (Clarias gariepinus) FROM OGBA RIVER, BENIN CITY, NIGERIA.
The concentrations of heavy metals (Pb, Cd, Zn, Cu, Cr and As) in the myonematic, hepatic and renal tissues of the African catfish (Clarias gariepinus) from Ogba river, Benin City, Nigeria, were determined using a Unicam 929 series atomic absorption spectrophotometer. The concentrations of the aforementioned metals were also determined in water. The mean concentration of Pb ranged from 0.19mg/kg (muscle) to 0.39mg/kg (liver) while the mean concentration of Cd ranged from 0.03mg/kg (muscle) to 0.09mg/kg (liver). The mean concentration of Zn ranged from 0.09mg/kg( muscle) to 0.33mg/kg (liver) while the mean concentration of Cu ranged from 0.23mg/kg (muscle) to 0.76mg/kg(liver). The mean concentration of Cr ranged from 0.19mg/kg (muscle) to 0.41mg/kg (liver) while the mean concentration of As ranged from 0.36mg/kg (kidney) to 0.54mg/kg (muscle). The mean concentrations of the heavy metals in water were Pb(0.09mg/l), Cd(0.04mg/l), Zn(0.01mg/l), Cu(0.53mg/l), Cr(0.38mg/l) and As(0.59mg/l). With the exception of Cu, the mean concentrations of the heavy metals in water were generally above the World Health Organization (WHO) maximum allowable limit for the respective metals in drinking water implying that water from the river is unfit for human consumption owing to heavy metal contamination. The mean concentrations of Cr and As exceeded the WHO maximum allowable limits for fish food. The direct implication of this finding is that people who consume fish from the river are liable to potential health hazards resulting from Cr and As contamination.Â
Survival of Escherichia Coli in Lagos Lagoon
There was a gradual decrease in the population of Escherichia coli incubated in autoclaved and unautoclaved (raw) water samples obtained from three different sampling stations of the Lagos lagoon. The survival period of the bacterium was generally shorter in the unautoclaved than in the autoclaved water sample; and also varied with the season. In November, 1976, the survival periods in unautoclaved (raw) samples were 6 and 8 days respectively; while in February, 1977 they were 12 days for all three water samples. For the autoclaved water samples the survival periods in November 1976 were 12 and 14 days; while in February, 1977 they were 22, 24 and 32 days. The survival period was also affected by seasonal variations in some physic-chemical parameters of the lagoon
Haematological Indices of Broiler Chickens Administered Water Containing Medicinal Plant Leaf Methanol Extract
The discovery that the use of antibiotics in animal production is fueling the increasing problem of transmitting resistance bacteria from food animals to man has led to the search for an alternative to the use of antibiotics. Therefore, the response of broiler chickens fed various medicinal plants methanol extract as a replacement for antibiotics was investigated. The plant extracts encompass four available leaves; Gercinia kola (Bitter Kola), Alchornea cordifolia (Christmas bush), Pterocarpus santalinoides (Red scandal wood) and Chromolera Odorata (Hagony or Siam weed). A total of 180 unsexed Ross strain broiler chickens were randomly assigned to these dietary treatments which had 30 birds each. The treatments were replicated thrice with 10 birds per replicate in a Completely Randomized Design (CRD). Feed and water were provided ad libitum throughout the experiment which lasted for 56 days. Haematological indices of broiler chickens were evaluated. Significant differences (p<0.05) were observed in the mean values of all the hematological parameters measured across the treatment groups, except Packed cell volume and White blood cell. The result values obtained in this present study were within the standard range of PCV of normal birds with the reference range of 25.0 - 45.0%. However, the values obtained did not reveal any health problem. The findings of this study conclude that the medicinal plant methanol extracts have considerable potentials as component of broiler chicken diet. Alchornea cordifolia plant methanol extract can successfully be used to replace antibiotics at 1g/litre of drinking water for broiler production. Further research should be carried out on Alchornea cordifolia and other medicinal plants to examine their potentials and inhibitory characteristics
Testicular morphology and seminal fluid parameters of adult Wistar rats following honey administration
Purpose: Honey has a long history of use in the traditional medical systems This objective of this study was to find out the effects of honey on quality and quantity of sperm and testicular microstructure when compared to fertility boosting drug and controls.Methods: A total number of thirty (30) matured male Wistar rats that were sexually active weighing 200 - 280g were used for this study. The animals were grouped into five as A - E. Group A was the control; Group B (standard group) was the standard group that received 0.3ml of follicle stimulating hormone (FSH) drug for 6 days; groups C, D and E received 1ml, 2ml, and 2.5ml of honey daily for 21days respectively. After 21 days of administration, the testes were removed for analysis of the sperm parameters and the histology.Results: Honey significantly improved the sperm quality and spermatogenesis rate (denser seminiferous tubule lumen) of exposed animals compared to control animals, but most improvement was seen in the standard group that received 0.3ml FSH. Also no sign of degeneration or cellular loss was observable in the testicular histo-architecture of experimental animals.Conclusion: This research showed that honey possesses some fertility boosting properties in exposed animals compared to controls and honey is not associated with increased sperm abnormalities.Keywords: Honey, Fertility booster, Spermatozoa, Ologospermi
Inhibition of Dopamine Receptor in Neonate Hippocampus: Immunolocalization of Post Synaptic Density Protein-95 and Dopamine Receptor in vivo
The effect of haloperidol on neonatal dopaminergic neurotransmission in the hippocampus of postnatal day 20
rats (P.20) was investigated in this study. Haloperidol blocked dopamine receptors (D2R) and inhibited D2R on the
membrane of neonate neurons. For this study the 0.5 ml (20 mg/kg) of haloperidol was administered to pregnant
female animals intraperitoneally a week before delivery. At day P.20, 5 control animals and 5 haloperidol treated
animals were taken to the behavioral studies room for the Y maze and Novel object recognition test, which was done
7 am in the morning before mating. Electrophysiology was done with 2 control pups and 2 treated pups. Electrodes
were implanted in the brain at the hippocampal region 2 mm beneath the bregma, 2 mm lateral to the midline.
Anterior Posterior (AP=0), Medial Lateral (ML=2 mm). Also immunolocalization and immunofluorescence of post
synaptic density protein (PSD-95), hippocampal morphology and hippocampal neurons have been done
respectively. Results from this study showed a decline in memory index for the Y maze as a result of the effect of
D2R blockade thereby inhibiting neurotransmission in newborns. Electrophysiology result in this study showed an
increase in the root mean square (RMS) of control pups. The increase in RMS is equivalent to increase in wave
burst pattern caused by neuronal excitation. Immunochemistry result showed an increase in the number of PSD-95
in the hippocampus of an increase in tyrosine hydroxylase in the hippocampus of the treated neonatal rats when
compared to the control neonatal rats Immunofluorescence showed decline in the number of neurons in the
haloperidol treated rats and it also caused hippocampal damage in terms of morphology. Furthermore, results from
electrophysiology showed a statistical significant difference with P value 0.04229 (P<0.05) using the student t-test.
These findings suggest that D2R inhibition may cause decline in memory function, impair learning in newborns and
disrupt neonatal dopaminergic neurotransmissio
The practice of hepatocellular cancer surveillance in Nigeria
Background: Hepatocellular cancer is a disease of global and public health importance due to the widespread distribution of risk factors and associated high case fatality. Hepatocellular Cancer (HCC) in Sub-Saharan Africa is commonly seen among the younger age groups (<45 years) who present mostly in the terminal stage, when the disease is not amenable to any curative therapy. Hepatocellular Carcinoma surveillance employs the use of simple, cheap and readily available investigations, to detect early curable cancer in individuals with risk factors for HCC.Objectives:The aim of this study is to assess the practice of hepatocellular cancer screening among physicians.Methodolgy:This is a nationwide online survey carried out among physicians who care for patients with HCC. A questionnaire was sent out via a web link to all consenting doctors in Nigeria. The responses were collated in a cloud-based application and data was analysed using Epi-info version 20.Results:Atotal of 218 respondents, 142 were males (65.1 %) with a mean age of 37.6 ± 5.7 years. The modal age group was 31-40 years 153 (69.5%). The main factors considered as a hindrance to surveillance were; the cost of the tests (57.7%), failure of return of patients (50.5%) and not being aware of a surveillance program (45.2 %). The majority of the respondents were Gastroenterologists and Family Physicians. 54% of the gastroenterologists and 64% of the family physicians have never offered HCC surveillance to their patients.Conclusion:This survey highlights a knowledge gap in HCC surveillance among physicians. There is a need to make HCCsurveillance a daily routine among patients at risk by all physicians.
Keywords: Surveillance, Hepatocellular Carcinoma, HBV, HCV, Cancer screening
Global burden and strength of evidence for 88 risk factors in 204 countries and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
Background: Understanding the health consequences associated with exposure to risk factors is necessary to inform public health policy and practice. To systematically quantify the contributions of risk factor exposures to specific health outcomes, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 aims to provide comprehensive estimates of exposure levels, relative health risks, and attributable burden of disease for 88 risk factors in 204 countries and territories and 811 subnational locations, from 1990 to 2021. Methods: The GBD 2021 risk factor analysis used data from 54 561 total distinct sources to produce epidemiological estimates for 88 risk factors and their associated health outcomes for a total of 631 risk–outcome pairs. Pairs were included on the basis of data-driven determination of a risk–outcome association. Age-sex-location-year-specific estimates were generated at global, regional, and national levels. Our approach followed the comparative risk assessment framework predicated on a causal web of hierarchically organised, potentially combinative, modifiable risks. Relative risks (RRs) of a given outcome occurring as a function of risk factor exposure were estimated separately for each risk–outcome pair, and summary exposure values (SEVs), representing risk-weighted exposure prevalence, and theoretical minimum risk exposure levels (TMRELs) were estimated for each risk factor. These estimates were used to calculate the population attributable fraction (PAF; ie, the proportional change in health risk that would occur if exposure to a risk factor were reduced to the TMREL). The product of PAFs and disease burden associated with a given outcome, measured in disability-adjusted life-years (DALYs), yielded measures of attributable burden (ie, the proportion of total disease burden attributable to a particular risk factor or combination of risk factors). Adjustments for mediation were applied to account for relationships involving risk factors that act indirectly on outcomes via intermediate risks. Attributable burden estimates were stratified by Socio-demographic Index (SDI) quintile and presented as counts, age-standardised rates, and rankings. To complement estimates of RR and attributable burden, newly developed burden of proof risk function (BPRF) methods were applied to yield supplementary, conservative interpretations of risk–outcome associations based on the consistency of underlying evidence, accounting for unexplained heterogeneity between input data from different studies. Estimates reported represent the mean value across 500 draws from the estimate's distribution, with 95% uncertainty intervals (UIs) calculated as the 2·5th and 97·5th percentile values across the draws. Findings: Among the specific risk factors analysed for this study, particulate matter air pollution was the leading contributor to the global disease burden in 2021, contributing 8·0% (95% UI 6·7–9·4) of total DALYs, followed by high systolic blood pressure (SBP; 7·8% [6·4–9·2]), smoking (5·7% [4·7–6·8]), low birthweight and short gestation (5·6% [4·8–6·3]), and high fasting plasma glucose (FPG; 5·4% [4·8–6·0]). For younger demographics (ie, those aged 0–4 years and 5–14 years), risks such as low birthweight and short gestation and unsafe water, sanitation, and handwashing (WaSH) were among the leading risk factors, while for older age groups, metabolic risks such as high SBP, high body-mass index (BMI), high FPG, and high LDL cholesterol had a greater impact. From 2000 to 2021, there was an observable shift in global health challenges, marked by a decline in the number of all-age DALYs broadly attributable to behavioural risks (decrease of 20·7% [13·9–27·7]) and environmental and occupational risks (decrease of 22·0% [15·5–28·8]), coupled with a 49·4% (42·3–56·9) increase in DALYs attributable to metabolic risks, all reflecting ageing populations and changing lifestyles on a global scale. Age-standardised global DALY rates attributable to high BMI and high FPG rose considerably (15·7% [9·9–21·7] for high BMI and 7·9% [3·3–12·9] for high FPG) over this period, with exposure to these risks increasing annually at rates of 1·8% (1·6–1·9) for high BMI and 1·3% (1·1–1·5) for high FPG. By contrast, the global risk-attributable burden and exposure to many other risk factors declined, notably for risks such as child growth failure and unsafe water source, with age-standardised attributable DALYs decreasing by 71·5% (64·4–78·8) for child growth failure and 66·3% (60·2–72·0) for unsafe water source. We separated risk factors into three groups according to trajectory over time: those with a decreasing attributable burden, due largely to declining risk exposure (eg, diet high in trans-fat and household air pollution) but also to proportionally smaller child and youth populations (eg, child and maternal malnutrition); those for which the burden increased moderately in spite of declining risk exposure, due largely to population ageing (eg, smoking); and those for which the burden increased considerably due to both increasing risk exposure and population ageing (eg, ambient particulate matter air pollution, high BMI, high FPG, and high SBP). Interpretation: Substantial progress has been made in reducing the global disease burden attributable to a range of risk factors, particularly those related to maternal and child health, WaSH, and household air pollution. Maintaining efforts to minimise the impact of these risk factors, especially in low SDI locations, is necessary to sustain progress. Successes in moderating the smoking-related burden by reducing risk exposure highlight the need to advance policies that reduce exposure to other leading risk factors such as ambient particulate matter air pollution and high SBP. Troubling increases in high FPG, high BMI, and other risk factors related to obesity and metabolic syndrome indicate an urgent need to identify and implement interventions
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