Polycyclic Aromatic Hydrocarbon, Haematological and Oxidative Stress Levels in Commercial Photocopier Operators In Lagos, Nigeria

Background: Human exposure to hazardous substances in the environment has been known to play an important role in the pathogenesis of some diseases. Photocopying machines have become a cheap source of self-employment in Nigeria. For obvious reasons the highest level of patronage is encountered in the campuses of educational institutions. However, the persons who operate the machines are always exposed to possible hazards associated with the job without protective devices.Objective: This study investigated the levels of oxidative stress, polycyclic aromatic hydrocarbon (PAH) and haematological parameters in blood samples of photocopier operators.Methods: The experimental procedure involved 50 consented subjects selected based on some criteria. The haematological parameters, oxidative stress and PAH levels were determined using standard methods.Results: The results showed no significant difference (p ≥ 0.05) in the haematological parameters between the test subjects and the controls. However, there were duration on the job (yrs) dependent significant decrease in the level of superoxide dismutase (SOD) of the photocopier operators compared with the controls (> 5 years p≤ 0.0001; 4-5 years p≤0.001). The level of reduced glutathione (GSH) was significantly decreased across all lengths of duration on the job compared with the controls.Conclusion: The findings in this study revealed increased level of oxidative stress in photocopier operators with no significant change in haematological parameters. The health implication of operating photocopiers call for quick health education and intervention tailored to monitoring and guiding the photocopier operators. This will help to prevent or manage continuous exposure to the hazards of photocopying machines.Keywords: Photocopier operators, oxidative stress, PAH, haematology, Nigeria

Genetic variants in novel pathways influence blood pressure and cardiovascular disease risk.

Blood pressure is a heritable trait influenced by several biological pathways and responsive to environmental stimuli. Over one billion people worldwide have hypertension (≥140 mm Hg systolic blood pressure or  ≥90 mm Hg diastolic blood pressure). Even small increments in blood pressure are associated with an increased risk of cardiovascular events. This genome-wide association study of systolic and diastolic blood pressure, which used a multi-stage design in 200,000 individuals of European descent, identified sixteen novel loci: six of these loci contain genes previously known or suspected to regulate blood pressure (GUCY1A3-GUCY1B3, NPR3-C5orf23, ADM, FURIN-FES, GOSR2, GNAS-EDN3); the other ten provide new clues to blood pressure physiology. A genetic risk score based on 29 genome-wide significant variants was associated with hypertension, left ventricular wall thickness, stroke and coronary artery disease, but not kidney disease or kidney function. We also observed associations with blood pressure in East Asian, South Asian and African ancestry individuals. Our findings provide new insights into the genetics and biology of blood pressure, and suggest potential novel therapeutic pathways for cardiovascular disease prevention

A Meta-analysis of Gene Expression Signatures of Blood Pressure and Hypertension

Genome-wide association studies (GWAS) have uncovered numerous genetic variants (SNPs) that are associated with blood pressure (BP). Genetic variants may lead to BP changes by acting on intermediate molecular phenotypes such as coded protein sequence or gene expression, which in turn affect BP variability. Therefore, characterizing genes whose expression is associated with BP may reveal cellular processes involved in BP regulation and uncover how transcripts mediate genetic and environmental effects on BP variability. A meta-analysis of results from six studies of global gene expression profiles of BP and hypertension in whole blood was performed in 7017 individuals who were not receiving antihypertensive drug treatment. We identified 34 genes that were differentially expressed in relation to BP (Bonferroni-corrected p<0.05). Among these genes, FOS and PTGS2 have been previously reported to be involved in BP-related processes; the others are novel. The top BP signature genes in aggregate explain 5%–9% of inter-individual variance in BP. Of note, rs3184504 in SH2B3, which was also reported in GWAS to be associated with BP, was found to be a trans regulator of the expression of 6 of the transcripts we found to be associated with BP (FOS, MYADM, PP1R15A, TAGAP, S100A10, and FGBP2). Gene set enrichment analysis suggested that the BP-related global gene expression changes include genes involved in inflammatory response and apoptosis pathways. Our study provides new insights into molecular mechanisms underlying BP regulation, and suggests novel transcriptomic markers for the treatment and prevention of hypertension

New genetic loci link adipose and insulin biology to body fat distribution.

Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

Causal effect of plasminogen activator inhibitor type 1 on coronary heart disease

Background--Plasminogen activator inhibitor type 1 (PAI-1) plays an essential role in the fibrinolysis system and thrombosis. Population studies have reported that blood PAI-1 levels are associated with increased risk of coronary heart disease (CHD). However, it is unclear whether the association reflects a causal influence of PAI-1 on CHD risk. Methods and Results--To evaluate the association between PAI-1 and CHD, we applied a 3-step strategy. First, we investigated the observational association between PAI-1 and CHD incidence using a systematic review based on a literature search for PAI-1 and CHD studies. Second, we explored the causal association between PAI-1 and CHD using a Mendelian randomization approach using summary statistics from large genome-wide association studies. Finally, we explored the causal effect of PAI-1 on cardiovascular risk factors including metabolic and subclinical atherosclerosis measures. In the systematic meta-analysis, the highest quantile of blood PAI-1 level was associated with higher CHD risk comparing with the lowest quantile (odds ratio=2.17; 95% CI: 1.53, 3.07) in an age- and sex-adjusted model. The effect size was reduced in studies using a multivariable-adjusted model (odds ratio=1.46; 95% CI: 1.13, 1.88). The Mendelian randomization analyses suggested a causal effect of increased PAI-1 level on CHD risk (odds ratio=1.22 per unit increase of log-transformed PAI-1; 95% CI: 1.01, 1.47). In addition, we also detected a causal effect of PAI-1 on elevating blood glucose and high-density lipoprotein cholesterol. Conclusions--Our study indicates a causal effect of elevated PAI-1 level on CHD risk, which may be mediated by glucose dysfunction

Genetic associations at 53 loci highlight cell types and biological pathways relevant for kidney function.

Reduced glomerular filtration rate defines chronic kidney disease and is associated with cardiovascular and all-cause mortality. We conducted a meta-analysis of genome-wide association studies for estimated glomerular filtration rate (eGFR), combining data across 133,413 individuals with replication in up to 42,166 individuals. We identify 24 new and confirm 29 previously identified loci. Of these 53 loci, 19 associate with eGFR among individuals with diabetes. Using bioinformatics, we show that identified genes at eGFR loci are enriched for expression in kidney tissues and in pathways relevant for kidney development and transmembrane transporter activity, kidney structure, and regulation of glucose metabolism. Chromatin state mapping and DNase I hypersensitivity analyses across adult tissues demonstrate preferential mapping of associated variants to regulatory regions in kidney but not extra-renal tissues. These findings suggest that genetic determinants of eGFR are mediated largely through direct effects within the kidney and highlight important cell types and biological pathways

Survey of rabies virus antibodies in confined, hunting and roaming dogs in Ogun and Oyo states, Nigeria

In view of the recent upsurge in adoption of exotic and local dogs as pets in Nigeria associated with increased contact between the dogs and their owners, and the traditional close relationship between hunters and their dogs, there is a need for studies to determine the level of protection of these dogs against rabies. In this study, a community-based approach involving administration of questionnaires to dog owners was adopted to screen for rabies virus (RABV) antibodies in apparently healthy confined, hunting and roaming dogs. Sera from 230 (80 confined, 92 hunting and 58 roaming) dogs in some urban and peri-urban communities in Ogun and Oyo states, southwestern Nigeria were screened for RABV antibodies using the indirect ELISA method. Analysis of administered questionnaires showed that of 80 confined dog owners, 37 were aware of anti-rabies vaccination (i.e. they were informed) while 17 were negligent and 26 uninformed. Of the 230 sera tested, only 13 (5.7%) from vaccinated confined dogs in Oyo state were positive i.e. had optimal RABV antibody titres (mean 0.54; 95% CI: 0.42 – 0.67) while all confined dog sera in Ogun state were negative. Eleven (12.0%) and 14 (24.1%) of the hunting and roaming dogs respectively had sub-optimal RABV antibody titres while the rest were negative. Evidently, these groups of dogs are a totally unprotected and susceptible dog population that can serve as potential reservoirs of RABV in the study area. Moreover, the presence of sub-optimal RABV antibody levels in unvaccinated hunting and roaming dogs suggests they have had field exposure to rabies or rabies-related viruses. Responsible pet ownership, vaccination of hunting and roaming dogs, integration of veterinary and public health services in implementing mass dog vaccination programmes and community-based active rabies surveillance are therefore advocated in Nigeria.Keywords: Rabies virus, antibodies, confined, hunting and roaming dogs, southwestern Nigeria

Quality of gari (roasted cassava mash) in Lagos State, Nigeria

Gari is creamy-white, partially gelatinized roasted free flowing granular flour made from cassava roots. It is a major staple consumed in both urban and rural areas due to its convenience. Quality of Gari (roasted cassava mash) in Lagos, Nigeria was investigated. Gari samples werecollected at random from different processors and sellers in major urban and rural markets of three-selected local governments in Lagos state. The samples were then analyzed for chemical and functional properties. The cyanide level of gari from Ikorodu and Epe local government areas (excluding that from Epe rural processor) falls within the recommended standard of 20 mg HCN/kg by the Standard Organization of Nigeria(SON). The ash and crude fibre contents of all the samples fall within the standard of 1.5% - 2.0% and the moisture content of all samples (9.73% - 14.87%) falls within the normal range for storage up to seven months. The peak viscosity, ranged from 195.00–373.33 RVU. Badagry rural producer had the highest peak viscosity (at a temperature of 64.05o C in 4.72 minutes) and Ikorodu rural producer had the lowest (at temperature of 64.15oC in 4.40 minutes). The breakdown viscosity ranged from 56.67 RVU – 238.25 RVU with Badagry rural processor gari having the highest and gari from Epe urban processor (Ayetoro) had the lowest. The final viscosity ranged from 195.92-315.33 RVU. Gari from Epe urban processor (Ayetoro) had the highest and that from Ikorodu rural processor had the lowest. The set back viscosity rangedbetween 47.25 and 101.42 RVU with gari from Gbogbo market of Ikorodu rural area having the highest and that from Poka market of Epe rural area having the lowest. There were significant differences (

Effect of Variety and Initial Moisture Content on Physical Properties of Improved Millet Grains

Physical properties of agricultural materials are important for the design of appropriate equipment and systems for harvesting and post-harvest operations such as cleaning, conveying and storage. The study was conducted to determine the effect of variety and initial moisture content on some physical properties of improved Nigerian millet grains. Improved varieties of millet obtained were conditioned to different moisture contents (10, 20 and 30%) and their physical properties were determined. The grain length, width, thickness and effective geometric mean diameter increased with increasing moisture content irrespective of millet varieties, while aspect ratio (which relates kernel width and length and determines whether grains will slide or roll on their flat surfaces during handling and processing) decreased with increase in moisture content. Static coefficient of friction ranged from 0.44 &#8211; 0.99, 0.45 &#8211; 0.82, 0.40 &#8211;0.70 and 0.37 &#8211; 0.67 for wood, mild steel, galvanized steel and glass respectively. The static coefficients of friction (an important parameter in predicting the lateral pressure on a retaining wall in storage bins or design of bins and hoppers for gravity flow) were found to increase as the moisture content increased. The study showed that variety and initial moisture content had significant effect (P&lt;0.05) on the physical properties determined. Hence, variety and initial moisture content are critical in the design of equipment for processing, handling and storage of millet grains