Excited States of Proton-bound DNA/RNA Base Homo-dimers: Pyrimidines

We are presenting the electronic photo fragment spectra of the protonated pyrimidine DNA bases homo-dimers. Only the thymine dimer exhibits a well structured vibrational progression, while protonated monomer shows broad vibrational bands. This shows that proton bonding can block some non radiative processes present in the monomer.Comment: We acknowledge the use of the computing facility cluster GMPCS of the LUMAT federation (FR LUMAT 2764

Predictors of Bovine TB Risk Behaviour amongst Meat Handlers in Nigeria: A Cross-Sectional Study Guided by the Health Belief Model

Bovine Tuberculosis (bTB) is still a serious public health threat in developing countries. The aim of this study is to determine the social and cognitive factors predicting one of the risk behaviours amongst meat handlers in Nigeria, namely, eating Fuku Elegusi. This is the practice of eating the visibly infected parts of the lung in-order to convince customers to buy meat. The study is guided by the health belief model (HBM).This is a cross-sectional study of 349 randomly selected meat handlers in Oko-Oba Abattoir, in Lagos State. Descriptive statistics and multiple logistic regression analysis were employed to determine perceptions and prevalence of risk behaviours and to identify predictors of eating Fuku Elegusi.Just over a quarter (28.1%) of the study participants knew that eating Fuku Elegusi could be a source of bTB in humans. The prevalence of eating Fuku Elegusi was found to be 22%. Across all knowledge indicators related to bTB, those who don't eat Fuku Elegusi exhibited better knowledge. Strong predictors of eating Fuku Elegusi were: being male (OR: 2.39, 95% CI: 1.10 to 5.19; p = 0.03), not knowing that eating Fuku Elegusi exposes to bTB (OR: 3.72, 95% CI: 1.69 to 8.22; p = 0.001), and the perception that one cannot sell meat without tasting it (perceived barrier) (OR: 1.35, 95% CI: 1.13 to 1.60; p = 0.001). Lower risk of eating Fuku Elegusi was predicted by perceived susceptibility to bTB due to another risk behaviour, namely, not washing hands after handling meat (OR: 0.78, 95% CI: 0.64 to 0.96; p-value = 0.021). Television and radio were the most acceptable media for TB prevention messages (78.5% and 75.6% respectively).Meat handlers in developing countries bear high risk to bTB owing to prevailing social and cognition determinants. Findings were largely consistent with the propositions of HBM

Foodborne Pathogens on Meat Stored in Major Central Cold Rooms in Ibadan and their Susceptibility to Antimicrobial Agents

Foodborne pathogens are the leading cause of illness and death in developing countries and are often associated with poor hygiene and unsafe food storage conditions. Using central cold rooms with alternate power supply in preserving meats due to erratic power supply is common among meat traders in Nigeria. However, the public health safety of the operations of this practice remains un-investigated. We conducted a microbial assessment of aseptically collected meat swabs from three selected major cold rooms in Ibadan for Staphylococcus aureus, Listeria monocytogenes, Salmonella spp. and Escherichia coli using standard procedures. Antibiotic susceptibility was determined using 14 different antibiotics at standard concentrations following Kirby-Bauer Assays. The data were analysed with Stata 12.0 using bivariate and logistic regression analyses. Of 180 meat swabs collected, 42.2 % were positive for S. aureus, 22.2 % for L. monocytogenes, 20.0 % for Salmonella spp. and 6.7 % for E. coli. All of the isolates exhibited total resistance to seven of the antibiotics. Escherichia coli showed the highest resistance to 12 antibiotics, followed by Salmonella spp. (11 antibiotics), L. monocytogenes (10 antibiotics) and S. aureus (7 antibiotics). Sampling locations were significantly associated with the prevalence of L. monocytogenes (P = 0.008) and S. aureus (P = 0.000), but not with Salmonella spp. (P = 0.435) or E. coli (P = 0.117). The study revealed a heavy microbial contamination with major foodborne pathogens characterized by a high level of antibiotic resistance. These findings portend that the current operations associated with the practice of using central cold rooms in meat preservation in Nigeria undermine public health safety and need to be urgently addressed

Prevalence and Economic Losses Due to Bovine Tuberculosis in Cattle Slaughtered at Bodija Municipal Abattoir, Ibadan, Nigeria

Bovine tuberculosis (BTB) is a zoonotic disease responsible for considerable economic losses; with consequent negative impact on both public health and the livestock industry. However, the burden of this disease and associated economic losses remain un-investigated among slaughtered cattle in Ibadan, the hub of livestock activities in south-western Nigeria. A cross sectional study was conducted over a three-month period to determine the prevalence and economic losses due to BTB among slaughtered cattle at the Bodija Municipal Abattoir, Ibadan, in south-western Nigeria. Individual slaughtered cattle were purposively inspected for the presence of tuberculous lesions, and representative sample of affected organs and associated lymph nodes from the BTB suspected animals were taken. The suspected lesions were processed based on Becton Dickinson digestion and decontamination procedure and the losses due to BTB were estimated mathematically, using a formula. The BTB prevalence of 9.3 % (38/408) was obtained with a significant statistical association (P ≤ 0.05) of the disease with the breeds of cattle slaughtered. Out of the 46 visceral organs condemned: 29 (63 %) were lungs, 12 (26.1 %) livers, 4 (8.7 %) hearts and 1 (2.2 %) kidney. The total estimated annual economic loss (direct and indirect) due to BTB was estimated as Nigerian naria NGN 703,980,070 (EUR 1,725,441.4). This study revealed BTB as endemic and a major cause of concern considering its ill-health and economic effects on both humans and the livestock industry. Efforts are therefore required: to control this disease along the beef value chain in order to safeguard human and livestock health; as well as to limit the economic losses associated with its prevalence

Seroprevalence of Brucella abortus and B. canis in household dogs in southwestern Nigeria: a preliminary report

A preliminary serological study of 366 household dogs in Lagos and Ibadan, southwestern Nigeria, was carried out to determine antibodies due to exposure to Brucella abortus and B. canis, using the rose bengal test (RBT) and the rapid slide agglutination (RSA) test, respectively. Results showed that 5.46 % (20/366) and 0.27 % (1/366) of the dogs screened were seropositive to B. abortus and B. canis, respectively.Of all dogs, 36 had a history of being fed foetuses from cows and 11 (30.6 %) of these tested positive in the RBT. Our findings, although based on a limited sample size and a dearth of clinical details, revealed that dogs in Nigeria may be infected with Brucella spp. given the wide range of risk factors. Further studies are recommended to elucidate the epidemiology of brucellosis in dogs and its possible zoonotic consequences in the country

Inhibitor design by wrapping packing defects in HIV-1 proteins

Two viral proteins, HIV-1 protease and HIV-1 integrase, have been targeted for inhibitor design to prevent assembly and maturation of HIV-1 virions. The enzymatic mechanism of these proteins involves side-chain groups that serve as general acids or bases. Furthermore, catalytic activity requires that water be removed from the microenvironment surrounding the chemical reaction site or be constrained to serve as an activated nucleophile. Here, we identify previously unrecognized structural features that promote water removal from polar catalytic regions. Packing defects in the form of hydrogen bonds that are insufficiently dehydrated intramolecularly, named “dehydrons,” are strategically placed in the structure to induce an anhydrous enzymatic pathway. Dehydrons become electrostatically enhanced and stabilized upon further desolvation. Thus, packing defects act synergistically with the polar active groups to enhance the enzymatic electrostatics. However, because dehydrons are sticky, they constitute targets for inhibitor design. We noticed that inhibitors attach to polar surfaces by further desolvating dehydrons, thus blocking the active sites or the sites involved in harnessing the substrate. The dehydrons are thus required for functional reasons, making them suitable targets. The differences in success when targeting HIV-1 protease, feline immunodeficiency virus protease, and HIV-1 integrase are rationalized in terms of the dehydron distribution, revealing possible improvements in the targeting strategy. Principles of design optimization are proposed to create an inhibitor that can be neutralized only at the expense of the loss of catalytic function. The possibility of using drugs that wrap dehydrons to block protein–protein associations is also discussed

Characterising quality traits of boiled yam: texture and taste for enhanced breeding efficiency and impact

Open Access ArticleBackground: Boiled yam key quality attributes typical for West African consumers are: crumbly, easy to break, and sweet taste. New yam varieties are being developed but high or medium throughput tools to assess the required quality traits and their range of acceptance are limited. This study assessed the acceptance thresholds of these quality attributes and established the predictive models for screening yam varieties that meet the required consumers' preferences. Results: Overall liking was associated with sweet taste, crumbly and easy to break (r values 0.502, 0.291 and -0.087, respectively). These parameters and selected biophysical parameters highly discriminated the boiled yam varieties. Crumbly texture and easy to break were well-predicted by penetration force and dry matter, whereas sweet taste by dry matter and sugar intensity. A high crumbliness and sweet taste are preferred (sensory scores above 6.19 and 6.22 for crumbly and sweet taste, respectively, on a 10 cm unstructured line scale), while a too high easiness to break is disliked (sensory scores ranging from 4.72 to 7.62). Desirable biophysical targets were between 5.1 and 7.1 N for penetration force, dry matter around 39% and sugar intensity below 3.62 g/100g. Some improved varieties fulfilled the acceptable thresholds, and the screening was improved through the deviation from optimum. Conclusion: The acceptance thresholds and the deviation from optimum for boiled yam assessed through the instrumental measurements are promising tools for yam breeders. This article is protected by copyright. All rights reserved