Characterization of diesel degrading bacterial species from contaminated tropical ecosystem

The bacterial diversity in a diesel contaminated tropical soil was investigated using diesel oxidation in gradient cultures dynamics (pH and OD) of the pure cultures. The diesel dependent growths of these isolates were assessed for 15 days by monitoring the gradient fluxes in the pH and Optical density OD of the media. Results showed an increase in OD as well as fluctuations in pH values. The mean OD data obtained was 0.515- 1.187 with pH of 6.95-7.2. From the morphological and biochemical characterization and comparison with respect to the standard references, the isolates S1P1, S3P3, S2P2, S2P1,and S3P2 were presumably the members of the genera Bacillus, Pseudomonas and Mycobacterium species. From the study, it was apparent that the tropical ecosystems contained unique organisms with the ability to deal with diesel contamination.

Biochemical impedance on intracellular functions of vitamin B12 in chronic toxigenic mold exposures.

A majority of patients with neurological disorders with chronic exposures to toxigenic molds and mycotoxins has vitamin B12 deficiency that is unrelated to dietary insufficiency. Vitamin B12 is a source of coenzymes, and participates in intracellular recycling of methionine, and in methionine synthase reactions. The biochemical processes that lead to B12 depletion and deficiency are not fully understood. This paper examines and assesses various most likely biochemical reasons that could impede upon the normal intracellular functions of vitamin B12 that lead to neurological manifestations. By biochemical implications and derivations, it is most likely that mycotoxins interrupt the structure and function of vitamin B12 through reactive interference with the normal One-Carbon metabolism leading to the observed clinical neurological manifestations such as nerve damage and, demyelination, degeneration of PNS leading to paralysis, progressive peripheral neuropathy, and spinal degeneration.

Health effects of long-term exposure to insecticide-treated mosquito nets in the control of malaria in endemic regions, revised.

The endemicity of malaria in tropical areas of the world persists, especially in countries south of Saharan Africa. The efforts and concerns invested by the World Health Organization and other health agencies to eradicate malaria are commendable. However, in spite of all these efforts, the loss in economic and human resources continues. In a previous report, the long-term health effects of insecticide-impregnated bednet (IIBN) use were highlighted with the expectation of attracting serious thoughts and further research on the issue. This present paper is an update on that expectation. Results from a comprehensive literature search show that not much work has been done on the effects of long-term exposure to IIBNs in combating malarial infection. The efficacy of IIBNs is not in question. What is in question is whether long-term exposure to IIBNs have any health effects. The aims and outcomes of the research found in the literature on the subject to date seem to support only the efficacy of the temporal use of plain bednets, but not the use of IIBNs, and do not tell much about the long-term effects of IIBN exposure. All pesticides are toxic by nature and present risks of adverse effects. While there is agreement that IIBNs can be effective in reducing malarial morbidity and mortality under field trials, a number of factors relating to their long-term-exposure health effects have yet to be determined. Further reliable research projects are recommended urgently. However, some of the anticipated behavioral effects caused by insecticidal use will be avoided by the use of untreated nets instead.

Clinical microbiological aspects of epileptic seizures in the tropical countries with specific focus on Nigeria.

Epilepsy is a common neurological disorder; however, in Nigeria and other tropical regions, the causes of epileptic seizures differ greatly in etiology. This paper is an attempt to highlight some possible microbiological aspects of epileptic seizures. A literature review was carried out to identify the extent to which microbial infections were involved in the elicitation of epileptic seizures. Data were collected from several clinics in the community and hospitals in Nigeria and correlated with the evidence from the literature review. It was found that different microbial agents including viral, bacterial, protozoa, and fungal agents were involved in several aspects of epileptic seizures. Malaria was found to cause more than 88% of childhood epileptic seizures and 12% of adult seizures. Generalized tonic-clonic seizures occurred in more than 40% of adult patients. Partial seizures were uncommon. Cases of epileptic seizures associated with bacteria (e.g., brucellosis), viral, fungal, and protozoa infections were frequently reported. Malaria, tapeworm, and cysticercosis were some of the common infectious causes of epilepsy; however, in some cases, the cause remained unknown. From these findings, it was evident that microbiological aspects of epilepsies are possible research areas that might be developed. It is believed that the unraveling of the various microbiological factors in epileptic seizures would have important implications for understanding the underlying neurobiology, evaluating treatment strategies, and perhaps planning health-care resources for the affected. It will also help to improve the prognostic factors in initial seizure symptomatic etiology and presence of any structural cerebral abnormalities.

Biochemical evaluation of antioxidant function after a controlled optimum physical exercise among adolescents.

Sensible physical exercise is shown to prevent certain neurovascular problems. However, in recent times, non-traumatic sudden death in young athletes has been observed and the incidence level is always very disturbing, because of the spontaneous nature of the occurrence. It most commonly occurs fivefold more in male than female athletes. Although it is believed that congenital cardiovascular disease is the leading cause of non-traumatic sudden athletic death, however, sudden physical alteration in the biochemical composition of the body system may, at least in part, play an important role. The role of antioxidants in the general maintenance of homeostasis has already been established. In this study, total antioxidant function in athletes subjected to controlled physical exercise was evaluated to determine the extent to which intensive physical exercise could alter the health conditions if adequate actions are not taken to adjust the biochemistry of the body system. Ten male field-track athletes were exercised using a fixed workload treadmill test. Blood samples were drawn before and after the exercise. The subjects exercised almost to their maximum running distance at a higher "fatigue" workload for a maximum of 20 min each day for five days. The lymphocytes' total antioxidant function was measured by addition of a peroxide (oxidative stress) to complete the medium. Lymphocyte growth response with peroxide was reported as a percentile of growth responses from a reference range of apparently healthy individuals. Values below the 25th percentile indicate a deficient antioxidant function. The results showed that although vitamin B3, B6, and B12 requirements were normal, there was a consistent low value in the total percentile of vitamins B1 (<79%), B2 (<54%), folate (<33%, and biotin (<70%). There was a dramatic decrease in the mean values of antioxidant function (38.1%) in all the subjects as opposed to the reference range of <75%. Overall reduction antioxidant function indicates decreased ability to resist oxidative stress, or an increased oxidant load, suggesting increased antioxidant utilization and/or cellular "tear and wear" scenario. It is therefore suggested that after intensive physical exercise, antioxidant functions should be monitored and supplemented whenever necessary to maintain the integrity of the cellular function.

Impact of hydrophobic pollutants' behavior on occupational and environmental health.

This paper reviews the influence of hydrophobic pollutant behavior on environmental hazards and risks. The definition and examples of hydrophobic pollutants are given as a guide to better understand the sources of release and the media of dispersion in the environment. The properties and behavior of hydrophobic pollutants are described and their influence on environmental hazard and risk is reviewed and evaluated. The overall outcome of the assessment and evaluation showed that all hydrophobic pollutants are hazardous and risky to all organisms, including man. Their risk effects are due to their inherent persistence, bioaccumulation potential, environmental mobility, and reactivity. Their hazardous effects on organisms occur at varying spatial and temporal degrees of emissions, toxicities, exposures, and concentrations.

Impacts of extraction methods in the rapid determination of atrazine residues in foods using supercritical fluid chromatography and enzyme-linked immunosorbent assay: microwave solvent vs. supercritical fluid extractions.

It is an accepted fact that many food products that we eat today have the possibility of being contaminated by various chemicals used from planting to processing. These chemicals have been shown to cause illnesses for which some concerned government agencies have instituted regulatory mechanisms to minimize the risks and the effects on humans. It is for these concerns that reliable and accurate rapid determination techniques are needed to effect proper regulatory standards for the protection of people's nutritional health. This paper, therefore, reports the comparative evaluation of the extraction methods in the determination of atrazine (commonly used in agricultural as a herbicide) residues in foods using supercritical fluid chromatography (SFC) and enzyme-linked immunosorbent assay (ELISA) techniques. Supercritical fluid extraction (SFE) and microwave solvent extraction (MSE) methods were used to test samples of frozen vegetables, fruit juice, and jam from local food markets in Houston. Results showed a high recovery percentage of atrazine residues using supercritical fluid coupled with ELISA and SFC than with MSE. Comparatively, however, atrazine was detected 90.9 and 54.5% using SFC and ELISA techniques, respectively. ELISA technique was, however, less time consuming, lower in cost, and more sensitive with low detection limit of atrazine residues than SFC technique.

AIDS-related stigma in sub-Saharan Africa: its contexts and potential intervention strategies.

BACKGROUND: AIDS-related stigma discourages individuals who are aware of their HIV-positive status from sharing information about their status with their sexual partners and families, and makes it difficult to prevent the spread of the infection or to plan a secure future for surviving children and family members. It is essential that barriers to screening, prevention, and care are understood and removed so that persons living with HIV/AIDS can benefit optimally from available health and social services. OBJECTIVES: The objectives of this article are to summarize the literature on barriers posed by stigma to HIV/AIDS prevention and care in sub-Saharan Africa, to analyze the contexts in which AIDS-related stigma and discrimination are manifested, and to suggest potential prevention strategies. METHODS: The authors collected and reviewed published studies from standard research databases and reference lists of relevant articles. RESULTS: The ways in which AIDS stigma is overtly or covertly expressed are shaped by a range of social, cultural, political, and economic factors. Stigma plays into existing social inequalities and is manifested at all levels: in the wider society, in institutions, in families, and at the individual level. IMPLICATIONS FOR POLICY AND PRACTICE: Influences on AIDS-related stigma and discrimination are rooted in the structure of communities and societies, and therefore effective interventions should be based on a sound theoretical foundation and include attention to individual as well social and structural barriers. Given the diversity of cultures among the various countries in Africa, interventions to reduce AIDS stigma are likely to be more effective if they are context-specific and sensitive to the prevailing sociocultural and economic environment of each country.

Assessing the health effects of long-term exposure to insecticide-treated mosquito nets in the control of malaria in endemic regions.

Malaria is a protozoan disease caused in humans by the genus Plasmodium of which four species are known: P. falciparum, P. vivax, P. ovale, and P. malariae. It is transmitted through the bite of infected female mosquitoes of the genus Anopheles. Malaria is endemic in tropical and subtropical regions of the world. It is characterized by extreme exhaustion associated with paroxysms of high fever, sweating, shaking chills, and anemia. Approximately 40% of the world''s population, mostly those living in the poorest nations, are at risk. Much of the deaths due to malaria occur in Africa, mostly among children. The search for prevention and control interventions that are effective and sustainable remains an abiding challenge for national governments and international health agencies. To this end, the World Health Organization and several nongovernmental organizations are investing in the use of insecticide-treated mosquito nets (ITMNs) as a viable option. Trials of ITMNs in the 1980s and 1990s showed that they reduce deaths in young children by an average of 20% and multilateral agencies, spearheaded by Roll Back Malaria (RBM), seek to have 60% of the populations at risk sleeping under ITMNs by 2005. All pesticides are toxic by nature and present risks of adverse effects that depend on toxicity of the chemical and the degree of exposure. While there is agreement that ITMNs can be effective in reducing malaria morbidity and mortality under field trials, a number of factors relating to their sustainability and contribution to health improvement in less-developed countries have yet to be determined. In particular, the adverse effects associated with their long-term use and misuse has yet to be fully evaluated. Although this paper examines potential neurotoxic and neurobehavioral effects of long-term use of ITMNs and discusses priority public health actions for protecting the health of users, it forms the basis for further research.