Charting achievements: a two-year retrospective of the society for environmental geochemistry and health (SEGH) and the evolving strategies.

Emerging from the shadow of the COVID-19 pandemic, it is time to ground ourselves and retrospectively assess the recent achievements of SEGH over the past years. This editorial serves as a comprehensive report on the progress made in comparison to the aspirations and goals set by the society's board in 2019 (Watts et al., Environ Geochem Health 42:343-347, 2019) (Fig. 1) and reflects on the state of the SEGH community as it reached its 50th anniversary at the close of 2021 (Watts et al. Environ Geochem Health 45:1165-1171, 2023). The focus lies on how the SEGH community navigated through the extraordinary challenges posed by the COVID-19 pandemic since early 2020, and to what extent the 2023 targets have been met.

Latent Tuberculosis among Human Immunodeficiency Virus (HIV) Positive Patients: Prevalence and Correlates.

BACKGROUND: Tuberculosis is the most common opportunistic infection affecting HIV-infected individuals and it remains the most common cause of death in patients with AIDS. Detection of latent tuberculosis and treatment largely prevents the development of active disease. OBJECTIVE: This study was to determine the prevalence and factors associated with latent TB in HIV-positive patients. METHODOLOGY: This is an analytical cross-sectional study which involved 160 consented patients. Active tuberculosis was excluded using signs, symptoms and laboratory tests. All participants were tested using Quantiferon TB Gold Plus test kits. Data analysed with SPSS version 25.0 included patient's demographics, clinical and laboratory features. P< 0.05 was considered significant. RESULTS: The mean age of HIV-infected patients was 42.69 ± 9.91 years and the mean age of the control was 41.29 ± 9.20 years with no significant statistical difference. The prevalence of latent tuberculosis among HIV-infected patients was found to be 22.50% while among controls was 10.0% which was statistically significant (p-0.001). CD4 cells count was observed to inversely predict latent tuberculosis (OR = 1.41; CI = 1.01-3.73) while viral load was found to directly predict latent tuberculosis (OR = 1.63; CI=1.04-4.25). CONCLUSION: The prevalence of latent tuberculosis infection is significantly higher among HIV-positive patients when compared with HIV-negative patients. Also, the prevalence of HIV infection was higher amongst the female and less educated population.

CONTEXTE: La tuberculose est l'infection opportuniste la plus courante chez les personnes infectées par le VIHet reste la cause la plus fréquente de décès chez les patients atteints du SIDA. La détection de la tuberculose latente et le traitement empêchent largement le développement de la maladie active. OBJECTIF: Cette étude visait à déterminer la prévalence et les facteurs associés à la tuberculose latente chez les personnes séropositives. MÉTHODOLOGIE: Il s'agit d'une étude transversale analytique qui a porté sur 160 patients consentants. La tuberculose active a été exclue à l'aide de signes, de symptômes et de tests de laboratoire. Tous les participants participants ont été testés à l'aide de kits de test Quantiferon TB Gold Plus. de Quantiferon TB Gold Plus. Les données analysées avec SPSS version 25.0 comprenaient les caractéristiques démographiques, cliniques et de laboratoire des patients. P< 0,05 a été a été considéré comme significatif. RÉSULTATS: L'âge moyen des patients infectés par le VIH était de 42,69 ± 9,91 ans et l'âge moyen du groupe témoin était de 41,29 ± 9,20 ans., sans différence statistic significative. La prevalence de tuberculose latente chez les patients infectés par le VIH était de 22,50 % alors qu'elle était de 10,0 % chez les témoins, ce qui était statistiquement significative (p-0,001). On a observé que le nombre de cellules CD4 de prédire de façon inverse la tuberculose latente (OR = 1,41; IC = 1,01- 3,73), tandis que la charge virale prédit directement la tuberculose latente (OR = 1,63 ; IC = 1,04-4,25). CONCLUSION: la prévalence de l'infection tuberculeuse latente est significativement plus élevée chez les patients séropositifs par rapport aux patients séronégatifs. De même, la prévalence de l'infection par le VIH était plus élevée chez les femmes et les personnes peu moins éduquée. Mots clés: Bacilles acido-alcoolo-résistants, indice de masse corporelle, extrapulmonaire, virus de l'immunodéficience humaine, interféron gamma, immunodéficience, tuberculose latente, ZiehlNeelsen.

Farmers' choice of genotypes and trait preferences in tropically adapted chickens in five agro-ecological zones in Nigeria.

This study aimed at determining chicken genotypes of choice and traits preference in chicken by smallholder farmers in Nigeria. Data were obtained from a total of 2063 farmers using structured questionnaires in five agro-ecological zones in Nigeria. Chi square (χ2) statistics was used to explore relationships between categorical variables. The mean ranks of the six genotypes and twelve traits of preference were compared using the non-parametric Kruskal-Wallis H (with Mann-Whitney U test for post hoc separation of mean ranks), Friedman, and Wilcoxon signed-rank (with Bonferroni's adjustments) tests. Categorical principal component analysis (CATPCA) was used to assign farmers into groups. Gender distribution of farmers was found to be statistically significant (χ2 = 16.599; P ≤ 0.002) across the zones. With the exception of Shika Brown, preferences for chicken genotypes were significantly (P ≤ 0.01) influenced by agro-ecological zone. However, gender differentiated response was only significant (P ≤ 0.01) in Sasso chicken with more preference by male farmers. Overall, FUNAAB Alpha, Sasso, and Noiler chicken were ranked 1st, followed by Kuroiler (4th), Shika Brown (5th), and Fulani birds (6th), respectively. Within genotypes, within and across zones and gender, preferences for traits varied significantly (P ≤ 0.005 and P ≤ 0.01). Traits of preference for selection of chicken breeding stock tended towards body size, egg number, egg size, and meat taste. Spearman's rank order correlation coefficients of traits of preference were significant (P ≤ 0.01) and ranged from 0.22 to 0.90. The two PCs extracted, which explained 65.3% of the variability in the dataset, were able to assign the farmers into two groups based on preference for body size of cock and hen and the other ten traits combined. The present findings may guide the choice of appropriate chicken genotypes while the traits of economic importance may be incorporated into future genetic improvement and conservation programs in Nigeria.

High risk sexual behavior among adolescent senior secondary school students in Nigeria.

BACKGROUND: The consequences of high risk sexual practices (HRSP) are enormous among adolescent senior secondary school students. They therefore need to have sufficient knowledge of HRSP. AIM OBJECTIVES: The study gauged the level of knowledge and perceptions of high risk sexual behavior among senior secondary school students in Ilorin, Nigeria with a view to improving their understanding of the current trends in HRSP.This was a quantitative, cross-sectional, descriptive study of adolescent secondary school students in Ilorin East Local Government Area. Multi - stage sampling method involving 3 stages was used. A semi-structured interviewer administered questionnaire was used to obtain data. Informed consent of respondents was obtained. The data was analyzed using SPSS windows software package version 17. RESULTS: Majority, 305 (69.5%) of the students were between 16 - 20 years. The major source of information was from movies, 42.5%, and the internet, 24.7%. Twenty-three percent (23.1%) had poor knowledge of HRSP. Thirty-eight percent (38.1%) did not consider indiscriminate sexual intercourse as HRSP while 27.9% still believed that unprotected sexual practice is safe. Thirty-four percent (34.2%) did not know that sex with multiple partners is a HRSP while 34.4% did not know that oral -genital sex is unsafe. Over thirty-two (32.9%) perceived that engaging in sex made them mature among peers. Twenty-four (24.7%) did not perceive any danger in keeping multiple sexual partners while 15.3% would still engage in unprotected sex. CONCLUSION: The students had relatively poor knowledge and perceptions of HRSP. Quite a number did not consider indiscriminate sexual intercourse as HRSP. An appreciable number did not perceive any danger in keeping multiple sexual partners or beingengaged in unprotected sex. Counselling on the dangers of HRSP should be a component of the school health services so as to curb the complications of HRSP in our secondary schools.

Methanogenesis control by employing various environmental stress conditions in two-chambered microbial fuel cells.

This study examines methanogen activity in microbial fuel cells when exposed to various environmental stresses, such as oxygen, low pH, low temperature, inhibitor (2-bromoethanesulfonate (BES)), and variations in external resistance. Controlling methanogenesis resulted in an increase in Coulombic efficiency (CE) because it was a major cause of electron loss. Methane was mainly produced from aceticlastic methanogenesis, rather than by syntrophic acetate oxidation, with Methanosarcinaceae being the primary contributor. Lowering the resistance from 600 to 50 Omega reduced the methanogenic electron loss by 24%; however, changing the temperature or pH level had little effect. A BES injection was the most potent strategy for the selective inhibition of methanogens without damaging exoelectrogens. The addition of 0.1-0.27 mM BES increased the CE from 35% to 70%. Oxygen stress successfully inhibited methanogens, while slightly suppressing the exoelectrogens, and is believed to be a practical option due to its low operating cost.

An antimalarial neem leaf extract has both schizonticidal and gametocytocidal activities.

A crude acetone/water (50/50) extract of neem leaves (IRAB) was evaluated for activity against the asexual (trophozoites/schizonts) and the sexual (gametocytes) forms of the malarial parasite, Plasmodium falciparum, in vitro. In separate 72 hour cultures of both asexual parasites and mature gametocytes treated with IRAB (0.5 microg/mL), parasite numbers were less than 50% of the numbers in control cultures, which had 8.0% and 8.5% parasitemia, respectively. In cultures containing 2.5 microg/mL, asexual parasites and mature and immature gametocytes were reduced to 0.1%, 0.2%, and 0% parasitemia, respectively. There were no parasites in the cultures containing 5.0 microg/mL. This extract, if found safe, may provide materials for development of new antimalarial drugs that may be useful both in treatment of malaria as well as the control of its transmission through gametocytes.

Concurrent pleomorphic adenoma in parapharyngeal space and submandibular gland.

BACKGROUND: Pleomorphic adenoma in the parapharyngeal space either occurs de novo or as an extension from the deep lobe of the parotid gland. CASE PRESENTATION: A rare synchronous occurrence of pleomorphic adenoma in the parapharyngeal space and submandibular gland of a 48-year-old Nigerian male is reported. CONCLUSION: Pleomorphic adenoma concurrent in the parapharyngeal space and submandibular gland is very rare. A complete surgical excision of both tumors is the treatment of choice.

The process of knowledge discovery from large pharmacokinetic data sets.

The advent of statistical software with powerful graphical and modeling capabilities has revolutionized the manner in which pharmacokinetic and pharmacodynamic analyses are performed. Knowledge discovery from a large (population) pharmacokinetic data set incorporates all steps taken from data assembly to the development of a population pharmacokinetic model and the communication of the results thereof. The process can be formalized into a number of steps: (1) creation of a data set for pharmacokinetic knowledge discovery, (2) data quality analysis, (3) data structure analysis (exploratory examination of raw data), (4) determination of the basic pharmacokinetic model that best describes the data and generating post hoc empiric individual Bayesian parameter estimates, (5) the search for patterns and relationships between parameters and parameters and covariates by visualization, (6) the use of modern statistical modeling techniques for data structure revelation and covariate selection, (7) consolidation of the discovered knowledge into irreducible form (i.e., developing a population pharmacokinetic model), (8) the determination of model robustness (determination of the reliability of model parameter estimates), and (9) the communication and integration of the discovered pharmacokinetic knowledge. This process is discussed, and a motivating example is presented. The use of modern graphical, modeling, and statistical techniques for knowledge discovery from large pharmacokinetic data sets has given the data analyst the freedom to choose statistical methodology appropriate to the problem at hand with the maximization of information extraction, rather than on the basis of mathematical/statistical tractability.

In vivo drug-drug interaction studies--a survey of all new molecular entities approved from 1987 to 1997.

Ninety-eight new molecular entities applications approved between 1987 to 1991 (period I) and 193 applications for new molecular entities between 1992 to 1997 (period II) were surveyed for drug-drug interaction studies. In period I (used as a comparator), 32 applications contained drug-drug interaction studies for a total of 117 studies. In period II, 106 applications reported drug-drug interaction studies, and the number of studies per new molecular entity ranged from 0 to 15. Most studies (77%) were performed in healthy subjects, with 44% using crossover designs, 7% using parallel designs, and the remaining using fixed sequence designs. The most common dosing scheme for new molecular entities/interacting drug was multiple dose (47%), whereas single dose/multiple dose was used in 31% of studies, and single dose/single dose was used in 18% of studies. Of the 540 drug-drug interaction studies submitted in period II, 80 (15%) resulted in clinically significant labeling statements. Submissions for new molecular entities to the Center for Drug Evaluation and Research divisions most likely to include drug-drug interaction studies were neuropharmacology, cardiorenal, antiviral, and antiinfective drugs. Some drug classes such as oncology drug products and radioimaging products were least likely to include drug-drug interaction studies in their submissions. We conclude that the use of drug-drug interaction studies in the drug development process has increased between the two periods.

Adverse drug reactions: a review of relevant factors.

We examined some of the factors that contribute to the development of adverse drug reactions (ADRs) and analyzed postmarketing ADR reports for 22 drugs. The role of metabolic-based drug-drug interaction in the development of ADRs can not be overstated. Assessment of the postmarketing ADR data for 22 drugs revealed that drugs with high potential for eliciting clinically significant ADRs are usually detected and either withdrawn from the market or placed on restricted use within the first year or two of marketing. Postmarketing data could be a useful tool for understanding the ADR profile of drugs if reporting can be adequately monitored and verified. It is hoped that early evaluation of the clinically meaningful factors such as metabolism, pharmacogenetics, and effect of physiologic and pathophysiologic states on the clinical effect of a drug during drug development would significantly reduce the incidence and severity of post-marketing ADRs.

FDA evaluations using in vitro metabolism to predict and interpret in vivo metabolic drug-drug interactions: impact on labeling.

Recent advances in in vitro metabolism methods have led to an improved ability to predict clinically relevant metabolic drug-drug interactions. To address the relationships of in vitro metabolism data and in vivo metabolism outcomes, the Office of Clinical Pharmacology and Biopharmaceutics in the Center for Drug Evaluation and Research, Food and Drug Administration, evaluated a number of recently approved new drug applications. The goal of these evaluations was to determine the contribution of in vitro metabolism data in (1) predicting in vivo drug-drug interactions, (2) determining the need to conduct an in vivo drug-drug interaction study, and (3) incorporating findings into drug product labeling. Ten cases are presented in this article. They fall into two major groups: (1) in vitro data were predictive of in vivo results, and (2) in vitro data were not predictive of in vivo results. Discussion of these cases highlights factors limiting predictability of in vivo metabolic interactions from in vitro metabolism data. The integration of these findings into drug product labeling is also discussed.

In vitro metabolic interaction studies: experience of the Food and Drug Administration.

A total of 194 new molecular entities approved by the Food and Drug Administration between 1992 and 1997 were surveyed to determine the role of in vitro metabolic interactions in the conduct of drug-drug interaction studies and to examine the methods used in these studies. Approximately 30% of the submissions were found to have in vitro metabolism-based interaction studies, most of which were inhibitory in nature. Chemical inhibition was the most commonly used approach in studying drug interactions in vitro. In this article, an attempt to assess the quality of the chemical inhibition approach was made. Four areas were found to be often overlooked: (1) incubation time and concentrations of the drug, (2) the difference between inhibition constant (k(i)) and 50% inhibitory concentration (IC50) values, (3) the substrate-dependent inhibition potential, and (4) the metabolic genotype or phenotype of the liver donor. We discuss the pitfalls in estimating drug interactions when these four areas are overlooked.

The bacteriology of neonatal septicaemia in Ile-Ife, Nigeria.

The incidence of septicaemia among neonates categorized as being at high risk was 55 per cent in Ile-Ife, Nigeria. Gram-positive organisms, specifically Staphylococcus aureus, were predominant (33.8 per cent) among bacteria cultured from proven cases of septicaemia. Other coagulase-negative staphylococci also contributed 21 per cent, with Staphylococcus epidermidis occurring in 5 per cent of the isolates. Listeria monocytogenes was cultured from 8.4 per cent of septic neonates. Pseudomonas aeruginosa was cultured from 3 per cent, Klebsiella pneumoniae from 14 per cent, and Escherichia coli from 7 per cent. Other Gram-negative bacilli cultured were Enterobacter aerogenes (5 per cent), Citrobacter freundii, Salmonella sp., and Proteus sp. (2 per cent each). The bacterial isolates were relatively resistant to antibiotics traditionally employed to treat cases of septicaemia. The study shows a high prevalence of neonatal bacterial sepsis at the centre and the emerging role of Listeria monocytogenes in the aetiology of neonatal sepsis. It highlights the preponderance of multiple antibiotic resistant organisms among these neonates early in life which is of epidemiological importance in the control of the infectious agents.

Biological effects of Myristica fragrans (nutmeg) extract.

The chloroform extract of nutmeg has been evaluated for antiinflammatory, analgesic and antithrombotic activities in rodents. The extract inhibited the carrageenan-induced rat paw oedema, produced a reduction in writhings induced by acetic acid in mice and offered protection against thrombosis induced by ADP/adrenaline mixture in mice.

Malaria in Nigeria: a revisit.

The frequency of asymptomatic malaria parasitaemia was investigated in rural and urban school-children aged six to 12 years in southwestern Nigeria between January 1987 and October 1988. Asymptomatic parasitaemia was detected in the rural school-children all year round with the lowest parasite rate in January and the highest in July, corresponding to the mid-dry and wet seasons respectively. Asymptomatic parasitaemia was also common amongst urban school-children, but the frequency was lower than in the rural children. Parasite density was less than or equal to 1000 microliters-1 in 42% of parasite-positive asymptomatic children and was greater than 10,000 microliters-1 in only 20% of them. Mass treatment with chloroquine, to which the parasites were fully sensitive, was followed by the same rate of re-infection in the parasite-positive and parasite-negative groups. Of 7713 patients clinically diagnosed as having malaria 4425 were found to have parasitologically-proven malaria, and of these 4239 had pure Plasmodium falciparum malaria. Of the patients with falciparum malaria only 4.6% were below the age of one year. In 47% the parasite count was less than or equal to 1000 microliters-1, and it was over 10,000 microliters-1 in 37% and over 250,000 microliters-1 in 16%. There was no significant difference between the asymptomatic children and the acutely ill patients in the percentage with parasite densities less than or equal to 1000 microliters-1, but the percentage with parasite densities greater than 10,000 microliters-1 was significantly greater in the acute malaria patients than in those with asymptomatic parasitaemia.

Demonstration of prostaglandin activity in lungs of the rainbow lizard (Agama agama) by bioassay.

Extracts and perfusate effluents of lungs of the rainbow lizard (Agama agama) were assayed for prostaglandin-like activity. Results of differential bioassay and thin-layer chromatography suggested that the prostanoid was predominantly PGE2-like. The mean PGE2-like content of 10 lizard lung extracts was 2.9 micrograms g-1 wet weight compared with 146 ng g-1 in rat lungs. Mechanical pressure applied to the lung during perfusion through the pulmonary vasculature provoked the release of large quantities of PGE2-like material. This release was blocked by fatty acid cyclooxygenase inhibitors. Compared with guinea-pig and rat lungs, lizard lungs exhibited a markedly low capacity for inactivating PGE2. In view of an apparently high prostaglandin-forming and a low inactivating capacity, we speculate that under certain circumstances, lizard lungs may release vasoactive substances into the circulation.

Comparison of the partitioning in vitro of chloroquine and its desethyl metabolites between the erythrocytes and plasma of healthy subjects and those with falciparum malaria.

The partitioning of chloroquine and its two desethyl metabolites between red blood cells (RBCs) and plasma was studied in vitro, using blood from healthy adults and from children with Plasmodium falciparum parasitaemia. Blood from the volunteers was incubated with varying concentrations of chloroquine (CQ), desethylchloroquine (DCQ) and bisdesethyl-chloroquine (BDCQ) for 15 min and the RBC/plasma concentration ratio determined. Desethylchloroquine and BDCQ were concentrated in the red cells of uninfected blood to the same extent as chloroquine. On the other hand, DCQ and BDCQ were concentrated to a significantly lower extent than CQ in the red cells from malarial children. The reduced ability of infected RBCs to concentrate DCQ and BDCQ may have an important bearing on the development of resistance to chloroquine by P. falciparum.

Distribution and urinary excretion of the desethylmetabolites of chloroquine in the rat.

The tissue distribution of desethylchloroquine and bisdesethylchloroquine has been studied in rats after single intraperitoneal administration of the drugs at a dose of 10 mg kg-1. Concentrations of the chloroquine metabolites in the liver, heart, lungs, kidney and spleen were 34 to 250 times higher than their plasma concentrations 24 h after the drugs had been injected. Urinary excretion of the drugs was studied in rats after single intravenous administration of 2.5, 5 or 10 mg kg-1 doses. The total estimated urinary excretion of desethylchloroquine and bisdesethylchloroquine was 25 and 64% respectively of the administered dose, with the maximum urinary excretion occurring on the first day. The results show that the desethylmetabolites of chloroquine are concentrated in the tissues in the same manner as the parent compound.