Toxicological and biochemical investigations in rats administered “kaun” (trona) a natural food additive used in Nigeria

Trona, a geological mineral, is often used as a natural food additive in many parts of Nigeria. This work was done to evaluate trona for metal content, acute toxicity and biochemical effects on vital organs such as the liver and the kidney. Consequently, graded doses of 10, 100, 1000, 1500 and 5000 mg trona per kg body weight were administered to determine their effects on body weight changes, relative organ weight, acute toxicity, liver and renal function indices and oxidative status of rats. Elemental analyses revealed the presence of high levels of sodium and iron, the presence of heavy metals such as cadmium, zinc and lead were also detected. There were losses in weights only at the 5000 mg/kg dose levels; relative liver and kidney weights were not affected. Acute toxicity tests recorded no mortality and no visible sign of toxicity. There were significant increases in ALT, AST and ALP activities at all dose levels except at the 10 mg/kg dose level. Liver MDA levels were significantly increased while catalase and SOD activities were significantly reduced in all the test rats compared with control. Kidney MDA levels were only affected at dose levels 5000 mg/kg; kidney SOD and catalase activities were not significantly affected. Creatinine, sodium and potassium levels were also not affected. These results show that trona may elicit toxic effects on the liver on prolonged administration, however no toxic effect was observed on the kidney within the duration of this study

The role of Mobile Phone Penetration on Foreign Direct Investment Inflow: Evidence of Sub-Saharan Africa

This study assesses the enhancing effect of mobile phone penetration on Foreign Direct Investment (FDI) for a panel dataset of all the 48 Sub-Saharan African countries, which is extracted from World Bank database between 2000-2018. This study adopts three distinct regression techniques such as Ordinary Least Square (OLS), Fixed Effect Regression (FE) and Generalized Moment of Method (GMM). Ordinary Least Square and Fixed Effect Regression tends to be biased and inconsistent. The results are defined as follows: (i) the coefficient estimates of the mobile phone penetration on FDI are positive and statistically significant; (ii) the net effect of mobile penetration remains positive on the FDI. The paper recommends that considering the low investment in the technology infrastructure and resultant benefits of the infrastructure in Sub-Saharan Africa, the governments in the region should make substantial investment in the localized technology, which in turn will encourage the foreign direct investment inflows into the region

Distribution of radionuclides and assessment of risk exposure to the miners on a kaolin field

Mining of kaolin deposits are common in Nigeria without considering the background radiation in such environment and the health risks it might pose on the miners. In this study, in-situ measurements of the naturally occurring radionuclides were carried out with the aim of determining the distribution of these radionuclides on the mining field and estimation of the hazard indices exposure risks (γ- and α-radiation risks) to the miners. The study was achieved with the aid of gamma ray detector Super-Spec (RS-125) and global positioning system. The detector used has ability to measure activity concentrations of 238U, 232Th and 40K and gamma doses. For the purpose of this study, only the concentrations of the three radionuclides were considered. For each location, measurements were taken four times, while its mean value was estimated for better accuracy. In all, nineteen locations were occupied in order to cover the study area. Basic kriging method was adopted for the production of spatial distribution of these radionuclides and their corresponding γ- and α-radiation hazard indices. The mean values of 238U, 232Th and 40K are 46.7, 71.8 and 108.7 Bq kg-1 , respectively. When compared to the global standard, it was revealed that 238U and 232Th are greater than the global standard, while 40K fall below the permissible limit. The γ- and α-radiation exposure risks estimated revealed that the mean values of Iγ and Iα are 0.6 and 0.2 respectively. Though the estimated γ- and α-radiation indices showed that the kaolin field is safe for the miners, periodic check is required in order to monitor the rate at which these natural primordial radionuclides (238U and 232Th and their progenies) are being enhanced

Knowledge of AIDS and HIV risk-related sexual behavior among Nigerian naval personnel

BACKGROUND: The epidemic of HIV continues to grow in Nigeria. Personnel in the military are at increased risk of HIV infection. Although HIV-risk related sexual behavior of Nigerian police officers has been studied, little is known about the sexual behavior of their counterparts in the Navy. This study describes knowledge of AIDS, and HIV-risk sexual behavior of naval personnel in Lagos Nigeria. METHODS: Four hundred and eighty personnel of the Nigerian Navy completed a 70-item questionnaire in 2002. Group discussion and in-depth interviews of four key informants were also conducted to gain insights into the context of risky sexual behaviors and suggestions for feasible HIV primary prevention interventions. RESULTS: The mean age of the respondents was 34 years. Although the overall mean AIDS knowledge score was 7.1 of 10 points, 52.1% of respondents believed that a cure for AIDS was available in Nigeria and that one can get HIV by sharing personal items with an infected person (25.3%). The majority (88.1%) had had lifetime multiple partners ranging from 1–40 with a mean of 5.1; 32.5% of male respondents had had sexual contact with a female sex worker, 19.9% did so during the six months preceding the survey. Forty-one percent of those with sexual contact with a female sex worker did not use a condom during the most recent sexual encounter with these women. Naval personnel who have been transferred abroad reported significantly more risky sexual behaviors than others. Group discussants and key informants believed that sex with multiple partners is a tradition that has persisted in the navy even in the era of AIDS because of the belief that AIDS affects only foreigners, that use of traditional medicine provides protection against HIV infection, and influence of alcohol. CONCLUSION: Many naval personnel report participating in high-risk sexual behavior which may increase their risk of acquiring and spreading HIV. Naval personnel live and interact freely with civilian population and are potential bridging group for disseminating HIV into the larger population. Interventions including sustained educational program, promotion of condoms, changes in transfer policies are recommended to address this problem

Investigating and combatting the key drivers of viral zoonoses in Africa: an analysis of eight epidemics

Investigating the interplay of factors that result in a viral zoonotic outbreak is difficult, though it is increasingly important. As anthropogenic influences shift the delicate balance of ecosystems, new zoonoses emerge in humans. Sub-Saharan Africa is a notable hotspot for zoonotic disease due to abundant competent mammalian reservoir hosts. Furthermore, poverty, corruption, and an overreliance on natural resources play considerable roles in depleting biological resources, exacerbating the population’s susceptibility. Unsurprisingly, viral zoonoses have emerged in Africa, including HIV/AIDS, Ebola, Avian influenza, Lassa fever, Zika, and Monkeypox. These diseases are among the principal causes of death in endemic areas. Though typically distinct in their manifestations, viral zoonoses are connected by underlying, definitive factors. This review summarises vital findings on viral zoonoses in Africa using nine notable case studies as a benchmark for future studies. We discuss the importance of ecological recuperation and protection as a central strategy to control zoonotic diseases. Emphasis was made on moderating key drivers of zoonotic diseases to forestall future pandemics. This is in conjunction with attempts to redirect efforts from reactive to pre-emptive through a multidisciplinary “one health” approach

Chapter 31 - Application of nanochitosan in tagging and nano-barcoding of aquatic and animal meats

Nanochitosans obtained from crustacean shells are biodegradable and biocompatible offering valuable functional, nutritional, and binding properties. Their low toxicity favors diverse industrial applications in various research models and can enable their use in the tagging of commercially sold aquatic and animal meat, easily contaminated by microbial sources during packaging, storage, and transportation. In this capacity, nanochitosans have been applied in fingerprinting for tracking and identifying the manufacturing and expiry dates of commercially sold meats and fish, as well as delivery of antioxidants and antimicrobials in these food products without affecting product consistency, composition, and organoleptic property. This chapter reviews current research on chitosan-based nanoparticles as barcodes and biosensors in tagging and monitoring aquatic and animal meats; and highlights methods of fish tagging and coding, and the benefits as well as the properties of materials used as biosensors in nano-barcoding of fish and meat

Utilization of nanochitosan for enzyme immobilization of aquatic and animal-based food packages

Studies have identified the properties of enzymes, functionalized molecules, and compounds in food industry applications as edible coatings and encapsulations, that assure prolonged food quality and standards. These molecules present benefits of longer shelf-life by delayed deterioration and inhibition of the proliferation of spoilage and mycotoxigenic microorganisms. However, challenges of reduced nutrient levels, miniaturized size, and low chemical stability remain concerning. Chitosan polymers naturally formed from the deacetylation of shellfish shells and exoskeletons of aquatic arthropods and crustaceans offer improved benefits when functionalized into nanoparticles as nanochitosans. These polysaccharides produced by the alkalescent deacetylation of chitin, comprise a series of 2-deoxy-2 (acetylamino) glucose linked by ß-(1-4) glycosidic linkages. This chapter considers the health impacts and

Nanochitosan derived from marine bacteria

Nanochitosans are polysaccharides produced by the alkalescent deacetylation of chitin and comprise a series of 2‐deoxy‐2 (acetylamino) glucose linked by ß‐(1‐4) glycosidic linkages. These are naturally formed from the deacetylation of shellfish shells and the exoskeleton of aquatic arthropods and crustaceans. Reports of chitosan production from unicellular marine bacteria inhabiting the sea, and possessing distinct animal‐ and plant‐like characteristics abound. This capacity to synthesize chitosan from chitin arises from response to stress under extreme environmental conditions, as a means of survival. Consequently, the microencapsulation of these nanocarriers results in new and improved chitosan nanoparticles, nanochitosan. This nontoxic bioactive material which can serve as an antibacterial agent, gene delivery vector as well as carrier for protein and drug release as compared with chitosan, is limited by its nonspecific molecular weight and higher composition of deacetylated chitin. This chapter highlights the biology and diversity of nanochitosan‐producing marine bacteria, including the factors influencing their activities, survival, and distribution. More so, the applications of marine bacterial nanochitosans in transfection and gene delivery; wound healing and drug delivery; feed supplement development and antimicrobial activity are discussed

Chapter 21 - Utilization of nanochitosan in the sterilization of ponds and water treatment for aquaculture

Water pollution constitutes the leading cause of infant mortality, neonatal deformities, and shrinkage of man’s average life expectancy. Pollutants come from point and nonpoint sources; and water pollution arises from the discharge of wastewater containing undesirable impurities used for domestic, agricultural, and industrial purposes. More so, high nutrient and wastewater runoffs from fish production systems contribute to the fouling and eutrophication of recipient water bodies. Hence, aquaculture which is inextricably linked to the natural environment is challenged by the dearth of appropriate water quantity and quality, militating against fish, and fishery production. Nanochitosans as polysaccharides produced by the alkalescent deacetylation of chitin, comprise a series of 2-deoxy-2 (acetylamino) glucose linked by ß-(1-4) glycosidic linkages. They are naturally formed from the deacetylation of shellfish shells and exoskeletons of aquatic arthropods and crustaceans. The unique attributes of chitin confer a wide range of biotechnological applications on the polymer, observed in flocculation as a wastewater treatment and purification route initiated by chitosan. This chapter highlights nanochitosan properties of aquaculture relevance; and elucidates the purification potentials of nanochitosan, compared to inorganic coagulants and organic polymeric flocculants. Effects of chitosan on contaminants and microorganisms, as well as applications in fish pathogens detection, fish disease diagnosis, and control are discussed