Cerebral Cortical Activity During Academic Stress Amongst Undergraduate Medical Students at Kampala International University (Uganda).

Background: Stress among medical students is related to their academic lifespan; however, information on brain health among medical students from developing countries continues to be scarce. The objective of this study was to establish perceived academic stress levels, assess the ability to cope with stress, and investigate its effects on the visual reaction time (VRT), audio reaction time (ART), and tactile reaction time (TRT) in the somatosensory cortex among medical students of Uganda. Methods: This was a cross-sectional study conducted among preclinical (n = 88) and clinical (n = 96) undergraduate medical students at Kampala International University Western Campus. A standard Perceived Stress Scale (PSS) was used to categorize stress into low, moderate, and severe while the ability to cope with stress was categorized into below average, average, above average, and superior stresscoper (SS). Data on reaction time were acquired through VRT, ART, and TRT using the catch-a-ruler experiment, and this was analyzed using SPSS version 20. Results: This study shows that preclinical students are more stressed than clinical students (PSS prevalence for low stress = preclinical; clinical: 40, 60%). Moderate stress was 48.4 and 51.6% while high perceived stress was 75 and 25% among preclinical and clinical students. Among male and female students in preclinical years, higher TRT and VRT were found in clinical students showing that stress affects the tactile and visual cortical areas in the brain, although the VRT scores were only significantly (P = 0.0123) poor in male students than female students in biomedical sciences. Also, highly stressed individuals had higher TRT and ART and low VRT. SS had high VRT and ART and low TRT in preclinical students, demonstrating the importance of the visual cortex in stress plasticity. Multiple regression showed a close relationship between PSS, ability to cope with stress, age, and educational level (P < 0.05), demonstrating the importance of social and psychological support, especially in the biomedical sciences. Conclusion: Preclinical students suffer more from stress and are poorer SS than clinical students. This strongly impairs their cortical regions in the brain, thus affecting their academic productivity.

Synergistic action of propolis with levodopa in the management of Parkinsonism in Drosophila melanogaster.

Background The Phosphatase and tensin-induced putative kinase 1 (PINK1B9) mutant for Drosophila melanogaster is a key tool that has been used in assessing the pathology of Parkinsonism and its possible remedy. This research was targeted toward determining the effects of ethanolic extract of propolis, with levodopa therapy in the management of Parkinsonism. Method The PINK1B9 flies were divided into groups and fed with the different treatment doses of ethanoic extract of propolis. The treatment groups were subjected to 21 days of administration of propolis and the levodopa at different doses after which percentage climbing index, antioxidant activity and lifespan studies were done. Results Propolis alone improved motor activity, antioxidant and lifespan in Drosophila melanogaster than in PINK1 flies. Propolis in combination with levodopa significantly (P<0.05) improved physiological parameters at higher than lower concentrations in Parkinsonism Drosophila melanogaster demonstrating its importance in managing side effects associated with levodopa. Conclusion Propolis is a novel candidate as an alternative and integrative medicinal option to use in the management of Parkinsonism in both animals and humans at higher concentrations.

Correction to: Antimalarial combination therapies increase gastric ulcers through an imbalance of basic antioxidative-oxidative enzymes in male Wistar rats.

An amendment to this paper has been published and can be accessed via the original article.

Antimalarial combination therapies increase gastric ulcers through an imbalance of basic antioxidative-oxidative enzymes in male Wistar rats.

OBJECTIVE: Antimalarials are globally used against plasmodium infections, however, information on the safety of new antimalarial combination therapies on the gastric mucosa is scarce. The aim of this study was to investigate the effects of Artesunate-Amodiaquine and Artemether-Lumefantrine on ulcer induction. Malondialdehyde (MDA), reduced glutathione (GSH) and major histological changes in male Wistar rats following ulcer induction using Indomethacin were investigated. Gastric ulcers were in four groups; Group I was administered Artesunate, group II received Artesunate-Amodiaquine, group III received Artemether-Lumefantrine, and group IV was a positive control (normal saline). Group V was the negative control consisting of healthy rats. RESULTS: Antimalarial combination therapies were associated with a high gastric ulcer index than a single antimalarial agent, Artesunate. In addition, levels of MDA were significantly higher in the combination of therapies while levels of GSH were lower in comparison to Artesunate and the negative control. Microscopically, antimalarial combination therapies were associated with severe inflammation and tissue damage than Artesunate in the gastric mucosa showing that antimalarial combination therapies exert their toxic effects through oxidative stress mechanisms, and this leads to cellular damage. Findings in this study demonstrate a need to revisit information on the pharmacodynamics of major circulating antimalarial agents in developing countries.

Thyroid hormones increase stomach goblet cell numbers and mucin expression during indomethacin induced ulcer healing in Wistar rats.

BACKGROUND: Gastric ulcers are mucosal discontinuities that may extend into the mucosa, submucosa or even deeper. They result from an imbalance between mucosal aggressors and protective mechanisms that include the mucus bicarbonate layer. Thyroid hormones have been shown to accelerate gastric ulcer healing in part by increasing the adherent mucus levels. However, the effects of thyroid hormones on goblet cell numbers and expression of neutral and acidic mucins during ulcer healing have not been investigated. METHODS: Thirty six adult male Wistar rats were randomly divided into six groups each with six animals. Group 1 (normal control) and group 2 (negative control) were given normal saline for eight weeks. Groups 3 and 4 were given 100 µg/kg per day per os of thyroxine so as to induce hyperthyroidism. Groups 5 and 6 received 0.01% (w/v) Propylthiouracil (PTU) for 8 weeks so as to induce hypothyroidism. After thyroid hormonal levels were confirmed using radioimmunoassay and immunoradiometric assays, ulcer induction was done using 40 mg/kg intragastric single dose of Indomethacin in groups 2, 3 and 5. Stomachs were extracted after day 3 and 7 of ulcer induction for histological examination. Histochemistry was carried out using Periodic Acid Shiff and Alcian Blue. The number of acidic and neutral goblet cells were determined by counting numbers per field. Mucin expression (%) was determined using Quick Photo Industrial software version 3.1. RESULTS: The numbers of neutral goblet cells (cells/field) increased significantly (P < 0.05) in the ulcer+thyroxine (14.67 ± 0.33), thyroxine (17.04 ± 1.71) and ulcer+PTU (12.89 ± 1.06) groups compared to the normal control (10.78 ± 1.07) at day 3. For the acidic goblet cells, differences between treatment groups were more pronounced at day 7 between the ulcer+thyroxine (22.56 ± 1.26) and thyroxine (22.89 ± 0.80). We further showed that percentage expression of both neutral and acidic mucins was significantly higher in the ulcer+thyroxine (9.23 ± 0.17 and 6.57 ± 0.35 respectively) and thyroxine groups (9.66 ± 0.21 and 6.33 ± 0.38 respectively) as compared to the normal control group (4.08 ± 0.20 and 4.38 ± 0.11 respectively) at day 3 after ulcer induction. CONCLUSION: This study confirms the role played by thyroid hormones in healing of indomethacin induced gastric ulcers. The study further demonstrates increased numbers of both neutral and acidic goblet cells and the increase in expression of both neutral and acidic mucins during healing of indomethacin induced ulcers.

Safety and antidiarrheal activity of Priva adhaerens aqueous leaf extract in a murine model.

ETHNOPHARMACOLOGICAL RELEVANCE: Priva adhaerens (Forssk.) Chiov., a wildly growing plant, is reported in central Uganda to be an effective traditional remedy for diarrhea. The objective of this study was to provide a scientific basis for the ethnopharmacological utility of this plant whose aqueous leaf and shoot extract was evaluated for acute toxicity and antidiarrheal activity using a murine model. MATERIALS AND METHODS: Acute toxicity of the aqueous leaf and shoot extract was assessed after determining the major phytochemicals present in the extract. The aqueous leaf and shoot extract was assayed against castor oil-induced diarrhea, transit time, and enteropooling, in comparison to loperamide, a standard drug. RESULTS: The oral LD50 value obtained for Priva adhaerens aqueous extract was greater than 5000mg/kg in rats; the aqueous leaf and shoot extract possessed several important phytochemicals. Furthermore, the aqueous extract significantly, and dose-dependently, reduced frequency of stooling in castor oil-induced diarrhea, intestinal motility, and castor oil-induced enteropooling in rats. CONCLUSION: This murine model shows that it is relatively safe to orally use the aqueous leaf and shoot extract of Priva adhaerens. The aqueous extract contains phytochemicals that are active for the treatment of diarrhea in a rat model.

Association of testosterone levels with socio-demographic characteristics in a sample of Ugandan men.

BACKGROUND: Testosterone, a male reproductive hormone, affects several physiological processes, such as sperm production, energy, strength, sexual behavior, sleep and the general well being of men. Normal levels of testosterone are necessary to effect these physiological processes. The objective of this study was to study the association between testosterone levels in a sample of Ugandan men with socio-demographic characteristics, and compare the testosterone levels of Ugandan men with that of men in other countries. METHODS: Eighty men were enrolled from the medical campus at Makerere University. Blood samples were drawn from 7.00 - 8.00 a.m. and total testosterone was measured using radioimmunoassay. The free and bioavailable testosterone was calculated after measuring sex hormone binding globulin (SHBG) and albumin in the blood samples. Self-administered questionnaires were used to obtain socio-demographic characteristics of the subjects. Biometric measurements including weight, height and waist circumference were also recorded. RESULTS: Serum testosterone levels of Ugandan men were within the normal physiological ranges. Married participants and those with dependents had lower testosterone than unmarried participants and those without dependents respectively. Sexually active participants had lower testosterone levels than those who were not sexually active. CONCLUSION: Testosterone levels were lower in association with several socio-demographic characteristics including being married, having dependents, and daily coital frequency. Further research is warranted into the relationship between testosterone levels and contributory sexual behavior that may be important in understanding the spread of HIV/AIDS, given its high prevalence in sub-Saharan Africa.