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.

Neurochemical changes in the aging process: implications in medication in the elderly.

Aging is an inevitable process in human development, which follows a time course that can be delayed, or hastened, by lifestyles, diseases and events. The factors that affect the aging process can be delayed, but not prevented. This paper evaluates the neurochemical changes in the aging process and their relevance in the modality of elderly medication. For clarity and understanding of the relevant neurobiochemical process and effects, the neuroanatomical, physiological, and neurobehavioral changes are reviewed as they relate to medication in the elderly.

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.

Female genital mutilation in developing countries: an agenda for public health response.

There is uncertainty regarding reasons for persistence of the practice of female genital mutilation (FGM) and the best strategies for intervening effectively. In spite of strong international condemnation, the persistence of FGM in many countries suggests that it can only be effectively eliminated when its practitioners are presented with a safe alternative that preserves their culture and, at the same time, protects the health and well being of women. Recognizing that there is no simple solution to the problem, this paper argues that interventions for preventing FGM should be non-directive, culture-specific and multi-faceted to be of practical relevance. Such interventions should not only motivate change, but should also help communities to establish practical means by which that change can occur. Potentially effective prevention interventions targeted at local practitioners of FGM, parents, at-risk adolescents, health and social workers, governments, religious authorities, the civil society, and communities are presented.

Metabolism of mycotoxins, intracellular functions of vitamin B12, and neurological manifestations in patients with chronic toxigenic mold exposures. A review.

This paper evaluates the possible reasons for consistent vitamin B12 deficiency in chronic toxigenic mold exposures and the synergistic relationships with the possible mycotoxic effects on one-carbon metabolism that lead to the manifestations of clinical neuropathological symptomology. Vitamins are first defined in general and the nutritional sources of vitamin B12 are evaluated in particular. Since patients with chronic exposures to toxigenic molds manifest vitamin B12 deficiencies, the role of mycotoxins in vitamin B12 metabolism is assessed, and since vitamin B12 plays important biochemical roles in one-carbon metabolism, the synergistic effects with mycotoxins on humans are reviewed. An outline of the proposed mechanism by which mycotoxins disrupt or interfere with the normal functions of vitamin B12 on one-carbon metabolism is proposed. The overall functions of vitamin B12 as a source of coenzymes, in intracellular recycling of methionine, in methionine synthase reaction, in the prevention of chromosome breakage, in methylation, and in maintaining a one-carbon metabolic balance are reviewed. Signs, symptoms, and clinical neurological indications of vitamin B12 deficiency are also cited. By implication and derivation, it is likely that the interruption of the structure and function of vitamin B12 would in turn interfere with the one-carbon metabolism leading to the neurological manifestations. This review is an attempt to formulate a basis for an ongoing research investigation on the subject.

Evaluation of the drug treatment and persistence of onychomycosis.

Onychomycosis is a common nail disease responsible for approximately 50% of diseases of the nail. It occurs more in the elderly, though several cases have been reported among children. Several factors influence, such as climate, geography, and migration. The two dermatophytes most commonly implicated in onychomycosis are Trichophyton rubrum and T. mentagrophytes, accounting for more than 90% of onychomycoses. Nonetheless, several other toxigenic molds have been implicated. For convenience, onychomycosis is divided into four major clinical presentations: distal subungal, which is the most common form of the disease; proximal subungal, which is the most common form found in patients with human immunodeficiency virus infection; superficial; and total dystrophic onychomycosis. Epidemiology of onychomycosis in adults and children is evaluated and the most common clinical symptoms addressed. Although the risk factors are discussed, the multifactorial nature of onychomycosis makes this inexhaustible. The diagnosis and treatments are difficult and the choice of appropriate antifungal drugs complex and require the knowledge of the chemical structures of the metabolites of the molds that cause onychomycosis and their interaction with the antifungal drugs. This is true because most of the antifungal drugs are derived from mold/fungal metabolism. Treatment with griseofulvin and amphotericin is displaced by the use of newer drugs from azole compounds, pyrimidines, and allylamines derivatives. Amorolfine, itraconazole, and ciclopirox nail lacquer solution 8 have gained support globally, but the side effects, drug resistance, and persistence of the disease are still a serious concern to the patients, just as economics and quality of life. Hence, the search for safer and more efficacious drug treatments are continuing.

Seasonal evaluation of antigenic bacterial infections among working class in the inner city of Houston.

This paper evaluates the monthly, quarterly, and seasonal variation of antigenic bacterial infections among the working class in the inner city of Houston using the Wellcogen Rapid Test methods. One of the aims was to demonstrate how this method could be used effectively in screening patients at risk and preventing the spread of antigenic bacteria such as Streptococcus pneumoniae, Haemophilus influenzae b, Streptococcus (Strep b), and Neisseria meningitidis (mainly group c and b). A total of 2,837 patients were screened for bacterial infections; 908 (32%) were male and 1,929 (68%) were female. The age range was between 2 and 70 years. Of the total group, 356 (12.5%) patients were positive; 203 (57%) were female while 153 (43%) were male (male/female ratio of 1:1.3). Medically underserved and immune suppressed populations are the most affected by these bacterial infections. Blacks are the most affected (48%) compared to Native Americans (1%), but children under 10 years of age have the highest incidence. This research showed, in addition, that the Wellcogen Rapid Tests are effective (356 cases identified) for a rapid screening of infectious bacteria. Explanation for these results was probably due to poor living conditions, poor hygiene, and viral immune suppression in adults and immature immune systems in neonates and children under 10 years of age.

Efficacy of sodium valproate in the treatment of photosensitive epilepsy (PSE) and the probable reasons for the persistence of occipital spikes.

Intermittent photic stimulation (IPS) in patients with photosensitive epilepsy (PSE) leads to EEG abnormalities, which include generalized discharges with spike and wave activity. This paper investigates 33 PSE patients, 14 (42%) males and 19 (58%) females. The age range was between 8 and 45 years. After the treatment of the patients with sodium valproate (VPA), the EEG examinations showed that the generalized discharges disappeared, while the occipital spikes persisted. The mechanism of action of VPA was re-evaluated in order to ascertain whether or not the persistent occipital was due to a failure in inhibitory postsynaptic potential (IPSP). It was concluded that the possible causes of VPA's inefficacy in abolishing occipital spikes in PSE was not necessarily due to a failure in IPSP, but rather it could be due to a time-dependent failure of certain cells of the visual system to respond positively to the VPA's modulatory activity, probably involving the ionic channels, neurotransmitters, and the second messenger systems. The relationship between occipital spikes and visual evoked response is discussed. The extent to which metabolic processes and neurotransmitters are involved is also evaluated.

Application, effectiveness, and limitations of the electrophysiological diagnosis of neurotoxic effects of chronic environmental mycotoxins in humans.

An extensive body of data demonstrates that diverse groups of mycotoxins can alter the structure and function of the nervous system in a variety of ways with notable human health consequences. Myconeurotoxicity refers to any adverse effects of exposure to mycotoxins or byproducts of primary and secondary mold metabolism, including volatile organic compounds (VOCs) on the structural or functional integrity of the developing or adult nervous system. Neuromycotoxic effects may involve a spectrum of biochemical, morphological, behavioral, and physiological abnormalities whose onset can vary from immediate to delayed action, following exposure to a mycotoxin, and whose duration may be transient or persistent and result in disability, while some may have life-threatening consequences. Myconeurotoxicity may result from effects of the mycotoxins acting directly on the elements of the nervous system or acting on other biological systems, which then adversely affect the nervous system. This paper reviews the application, effectiveness, and limitations of the electrophysiological diagnosis of myconeurotoxic effects of chronic environmental exposure to mycotoxins. The systemic targets of mycotoxic effects were reviewed for greater understanding as to why different neurophysiological test techniques have different levels of outcomes. Thus, nerve conduction velocity, sensory, motor, and evoked potentials, electroencephalographic techniques were evaluated using previously published papers and our clinical experience. Although, neuromycotoxic disorders can be established using clinical electrophysiological diagnosis, there is always the possibility of false positive and false negative results in some patients, which may be due to a multi-factorial etiopathogenesis of neuromycotoxicity. Detection of nervous system toxicity and other measures of toxicity could be achieved using a combination of these neurodiagnostic techniques.

Mass use of insecticide-treated bednets in malaria endemic poor countries: public health concerns and remedies.

Epidemiological evidence arising mainly from studies undertaken in sub-Saharan Africa suggests that sleeping under insecticide-treated mosquito nets is a cost-effective and efficacious method of controlling malaria. For this reason, promotion of use of insecticide-treated nets (ITNs) has become a key malaria control strategy. In 1999, the United Nations Children's Fund (UNICEF) and WHO set the goal of providing 32 million nets and 320 million net treatments a year for the next 10 years to protect 80% of African households against malaria. All pesticides are toxic by nature and are associated with adverse health risks that depend on the toxicity of each chemical, as well as the type and degree of exposure. Thus, massive scale-up of use of ITNs in malaria endemic poor countries can be expected to present tangible risks to health, especially where the insecticides for net treatment and re-treatment are handled mostly by untrained persons in uncontrolled settings. This paper examines potential health risks of mass use of ITNs in malaria endemic poor countries and calls for the implementation of strategies to minimize potential risks through careful selection of products, appropriate labeling (including labeling in the local languages of the user communities), pesticide safety education of the public and training of health personnel, and active monitoring of adverse health effects to document actual and potential hazards, and to facilitate planning of mitigation efforts.

Ocular defects in photosensitive epilepsy.

Patients with photosensitive epilepsy are susceptible to seizures due to photoparoxysmal response (PPR). This response adversely precipitates factors that modify the functional status of the visual system. Such factors may or may not be evident superficially, but may lead to ocular defects due to trauma, hormonal imbalance, abnormal intraocular pressure (IOP), or any other reflex-inducing stimuli. The extent to which photosensitive epileptic patients suffer from PPR-related ocular defects has not been documented fully. In this investigation, ocular defects in patients with photosensitive epilepsy are studied using visual-evoked response (VER). A total of 212 photosensitive epileptic patients were studied to ascertain the magnitude and distribution of ocular defects using the changes in EEG and visual-evoked potential (VEP); 51% of the patients were female, the age range was 1-46 years. The major ocular defects and complications found were visual field defects, optic nerve abnormalities, nystagmus, cataracts, amblyopia, and migraine. These findings were analyzed according to age and sex. The relationship between the ocular abnormalities and the interpretations of the changes in the characteristics of the VEP indicated that optic-related atrophies, visual defects, optic neuritis, chiasmal compression, nystagmus, migraine headache, cataracts, and amblyopia were prevalent in photosensitive epileptic patients at varying degrees. The results showed that although ocular defects in photosensitive epilepsy may not be obvious differentially, VEP can be used in their diagnosis, contrary to earlier studies reporting that VEP is not of much value in epilepsy diagnosis.

Mycotoxins and antifungal drug interactions: implications in the treatment of illnesses due to indoor chronic toxigenic mold exposures.

Chronic exposure to toxigenic molds in water-damaged buildings is an indoor environmental health problem to which escalating health and property insurance costs are raising a statewide concern in recent times. This paper reviews the structural and functional properties of mycotoxins produced by toxigenic molds and their interactive health implications with antifungal drugs. Fundamental bases of pathophysiological, neurodevelopmental, and cellular mechanisms of mycotoxic effects are evaluated. It is most likely that the interactions of mycotoxins with antifungal drugs may, at least in part, contribute to the observable persistent illnesses, antifungal drug resistance, and allergic reactions in patients exposed to chronic toxigenic molds. Safe dose level of mycotoxin in humans is not clear. Hence, the safety regulations in place at the moment remain inconclusive, precautionary, and arbitrary. Since some of the antifungal drugs are derived from molds, and since they have structural and functional groups similar to those of mycotoxins, the knowledge of their interactions are important in enhancing preventive measures.