Effect of 70% Ethanol Extract and its Solvent Fractions of Artemisia afra (Jacq. Ex Willd.) against Pentylenetetrazole-Induced Seizure in Mice.

INTRODUCTION: Artemisia afra (Jacq. ex Willd.), commonly called African wormwood, is a highly aromatic perennial herb and a well-known medicinal plant, claimed to be effective and safe in the treatment of epilepsy. The whole-plant extract is traditionally used as an antiepileptic agent in Ethiopia. Aim of the Study. The aim of this study was, therefore, to evaluate the anticonvulsant effect of the hydroethanolic extract and solvent fractions of A. afra whole part in mice. MATERIALS AND METHODS: The effects of A. afra hydroethanolic extract and its solvent fractions were evaluated against pentylenetetrazole- (PTZ-) induced convulsions in mice. The onset and duration of PTZ-induced convulsions were determined with hydroethanolic A. afra extract and its solvent fractions. Data were analyzed using a one-way analysis of variance (ANOVA) followed by post hoc Tukey's multiple comparisons test. p < 0.05 was considered statistically significant. RESULTS: The hydroethanolic extract of A. afra, with all the three doses of 250, 500, and 1000 mg/kg, showed a significant delay (504.833 ± 62.835 ∗ s; p < 0.05 ∗ ; 551.833 ± 47.69 ∗∗ s; p < 0.01 ∗∗ ; and 808.333 ± 64.8 ∗∗∗ s; p < 0.001 ∗∗∗ , respectively) in the mean onset of convulsion and a decrease (17.000 ± 1.88 ∗∗∗ s, p < 0.05 ∗ ; 13.000 ± 1.8 ∗∗ s, p < 0.01 ∗∗ ; and 7.833 ± 1.07 ∗∗∗ s, p < 0.001, respectively) in the mean duration of convulsion against PTZ-induced convulsion in a dose-dependent manner compared to the control (92.833 ± 13.006 s; 34.167 ± 3.683 s), and its anticonvulsant activity was significantly less compared to that of diazepam (1001.167 ± 68.430 s; 4.500 ± 0.619 s). The solvent fractions, however, did not show anticonvulsant activity against PTZ-induced convulsion. CONCLUSION: Crude extract of A. afra has an anticonvulsant effect in mice. This might be attributed to the synergistic effects of two or more active ingredients present in the herb.

COVID-19 Pandemic: A Compressive Review on Gender, Herd Immunity, and Physiological Mechanisms.

BACKGROUND: Researchers and scientists experienced the spread and aid recovery of the COVID-19 pandemic with a condition of great uncertainty. With limited understanding of SARS-CoV-2, current attempts at controlling its spread are focused on the suppressing approach (to reduce a sustained endogenous transmission) and the mitigating approach (to reduce the growth rate of the epidemic). On the one hand, while there has been no firm explanation, many governments have considered immunity passport and herd immunity for paths out of restrictive physical distancing measures imposed to control the spread of SARS-CoV-2 but were not successful. PURPOSE OF REVIEW: Herein, we attempted to systematize the lessons and shreds of evidence related to the spectrum of illness, the physiological mechanisms of host susceptibility, herd immunity, immunity passport, gender disparities, and severe challenges and uncertainties posed by the COVID-19 pandemic. We hope that the insights provided in this review will help raise the effectiveness of the treatment policies and preventive measures required to end the pandemic. RECENT FINDINGS: The use of immunity passports is suggested to certify an individual at low risk of acquiring or transmitting SARS-CoV-2. But, an individual might nevertheless carry the virus at similar levels and for a similar duration to those previously uninfected, with an unchanged potential for transmission. Vaccine-induced herd immunity is a complex issue inherent to a vaccine and the population receiving the vaccine. The central epidemiological questions about are as follows: what proportion of the population should be vaccinated to meet elimination (in a local program), eradication (in a global program) or a defined level of control? How is this affected by demographic factors (such as gender)? What is the best age at which to immunize? Besides, although age-dependent mortality risk is estimated to be higher for men and older people, such interpretation across gender, age groups, and countries, however, must be accepted with caution at present. SUMMARY: COVID-19 has taught us that health is the basis of global wealth and international solidarity is an essential response and a superior approach to isolationism. Hence, we must be clear about what the alternatives are when evaluating the merits of different ways of tackling this pandemic both in the short term as well as in the long term.

The magnitude of anemia and associated factors among adult diabetic patients in Tertiary Teaching Hospital, Northern Ethiopia, 2019, cross-sectional study.

BACKGROUND: Patients with Diabetic Mellitus are at higher risk of different complications. Many previous studies show that anemia among diabetic patients is poorly diagnosed. OBJECTIVE: This study aimed to assess the magnitude and associated factors of anemia among adult diabetes patients having regular follow up at the diabetic clinic of Ayder Comprehensive Specialized Hospital, Tigray, 2018/19. METHODS: This study was conducted the Diabetic clinic of Ayder comprehensive specialized hospital, Tigray regional state, Northern Ethiopia from January to March 2019. A systematic random sampling technique was used to select study participants. About 5 ml of venous blood was collected by experienced laboratory technologists under a complete aseptic technique. Two ml of the venous blood was used for hemoglobin determination. And three ml of the venous blood was used without any anticoagulant for creatinine determination. The association of variables was assessed using bivariate and multivariable analysis in the logistic regression model with p-value, odds ratio, and 95% CI in the SPSS version 24 software. RESULTS: From a total of 262 diabetes patients, forty-seven (17.9%) were found to be anemic (6.7% males and 11.5% females). Among the related factors, residency (Adjusted Odds Ratio, 7.69, 95% CI, 2.060, 28.69, p = 0.002,), age of the patients (Adjusted Odds Ratio, 4.007, 95%CI, 1.53-10.51, p = 0.005,) and sex (Adjusted Odds Ratio, 3.434, 95% CI, 1.582, 7.458, p = 0.042,) were significantly associated with anemia. CONCLUSION: According to this study, the magnitude of anemia is high among diabetic patients. Occupation of the participants, residency, HIV status, being female, and age was significantly associated with anemia.

Anemia in HIV/AIDS Patients on Antiretroviral Treatment at Ayder Specialized Hospital, Mekele, Ethiopia: A Case-Control Study.

BACKGROUND: Human immunodeficiency virus and anemia are the major public health problems in Sub-Sahara Africa. Untreated anemia is associated with rapid progression and poor prognosis of the disease in HIV. This study was aimed at determining the magnitude, severity and associated factors of anemia among HIV infected patients taking zidovudine and tenofovir-containing first-line HAART in Ayder Comprehensive Specialized Hospital, Mekele, Ethiopia. METHODS: A case-control study was conducted from February to August 2019 using both convenient and quota sampling methods. Anemia is defined as hemoglobin value below 13 g/dl for male and below 12 g/dl for female. Sociodemographic and clinical characteristics were assessed using a structured questionnaire, medical records, electronic weighing scale, adult height board, automated hematology analyzer (Sysmex XT-4000i), and Becton Dickinson's FACS caliber flow cytometer. Descriptive statistics, tables, graphs, Student's t-test and l logistic regression were used to analyze the data. RESULTS: About one-third (33.5%) of study participants were found to be anemic (ZDV: 20.3%; TDF: 13.2%, and p<0.05). Among these anemic cases, the majority was found to have mild, and the remaining was moderate types. The most common form was normocytic-normochromic anemia (46.5%). Cotrimoxazole prophylaxis, poor adherence, advanced AIDS stage at baseline and underweight at baseline were the factors associated with anemia in patients taking zidovudine-containing regimen (p<0.05). Advanced stage at baseline, cotrimoxazole prophylaxis, poor adherence status and lack of regular income were significantly associated with anemia in patients taking tenofovir-containing regimen (p<0.05). CONCLUSION: We find that the prevalence of anemia was significantly higher among patients taking ZDV-containing regimen. But different risk factors for anemia had been identified among ZDV-containing regimen, showing that appropriate follow-up, nutritional supplementation, continuous evaluation of patients on cotrimoxazole intake can reduce the risks of anemia in both types of regimens.

Changes in biochemical parameters by gender and time: Effect of short-term vegan diet adherence.

BACKGROUND: Vegetarian diets adapted for various reasons that may include religious, ethical, and health considerations have reasonable health benefits including weight loss, and favorable metabolic changes. However, studies that assessed health benefits associated with vegan diet practices during the Ethiopian Orthodox Christian (EOC) Lenten fasting remains limited. This study has, therefore, assessed how short-term vegan diet associated with metabolic traits, including weight, body mass index (BMI), circumference, blood pressure, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C), through longitudinal cross-sectional study design. METHODS: Seventy-five subjects (34 females and 41 males) with a mean age of [+SD] 27.3 + 5.8 years (range, 18 and 35) took part in the study. The study followed three assessment sessions: at baseline, during the Lenten (week 7), and 7 weeks after the end of the Lenten (week 14). An automatic chemistry analyzer (Mindray, BE-2000, China) used for lipid profile analysis. We used paired sample t-test in pre and post-performance and repeated measures ANOVA with Bonferroni post hoc adjustment between time points. The statistical significance was set at p < 0.05. RESULTS: The EOC fasting with vegan diet induced significantly lower blood pressure, weight, BMI, TC, HDL-C, LDL-C, and TC: HDL-C ratios, during Lenten (that is vegan diet consumption), but a regain noted in these parameters 7-weeks after Lenten (that is omnivore diet). On gender differences, vegan diet associated with significantly lower blood pressure, TC, and LDL-C in females compared with age-matched male counterparts. Some methodological limitations of this study are discussed with particular reference to lack of a randomized control group and self-reported data that limit this study in establishing a causal relationship through observed associations. CONCLUSIONS: Vegan diet consumption even for short period corroborate ideal metabolic traits, with more favorable changes noted in women than age-matched men counterparts. These findings might help to define vegetarian diets as part of religious fasting (beyond its spiritual goals) as a non-pharmacological prescription in different populations, and our findings add to growing evidence in these subjects.

Rewarding Effect of Catha edulis (Khat) and the Sex Differences to the Responses in Swiss Albino Mice.

BACKGROUND: Burden of substance abuse is becoming a worldwide problem. One of the psychostimulant plants widely consumed in Ethiopia and other East African countries is Catha edulis Forsk (khat). Most of the users claim that its stimulatory effect is the determinant factor that makes them use. However, its rewarding and reinforcing potential and variation between sexes have not been investigated. This study was, therefore, designed to measure the rewarding effect of khat extract (ke) in the addiction mice model of both sexes. MATERIALS AND METHODS: Forty-eight Swiss albino mice of both sexes (age 6-7 weeks) weighing 21-33 gm were used. The mice were conditioned to ke (100 mg/kg, 200 mg/kg and 300 mg/kg b.w). The control group was conditioned to tween 80 (2%, v/v) in distilled water. The reinforcing effect of khat was evaluated using the conditioned place preference paradigm. The classical pairing to the extract was made using the place conditioning box. Post-conditioning tests have been conducted four times and the average values were taken for analysis using SPSS version 21.0. RESULTS: Time spent in the khat-paired compartment was significantly higher for mice conditioned to ke 200 mg/kg (p<0.05) and ke 300 mg/kg (p<0.001). The rewarding effect of khat was strong in females at a higher dose when compared to the same sex of mice conditioned to the vehicle (p<0.001) or male mice conditioned to the same dose of khat extract (p<0.05). Repeated administration increased khat rewarding sensitization at all doses. Though the crude khat extract did not affect the food consumption and total body weight, water consumption was significantly less in mice received ke 100 mg/kg (p<0.01), where it was significantly higher in mice received ke 300 mg/kg (p<0.01). Sniffing (p<0.05) and climbing (p<0.05) psychomotor activities of mice were also affected by the crude khat extract. CONCLUSION: Mice showed place conditioning to khat extract, and the response was significantly higher in female mice. The crude khat extract did not affect food consumption and total body weight. The mechanisms behind the rewarding response of khat extract and sexual differences should be investigated.

Evaluation of Acute and Sub-Acute Toxicity of Aqueous Extracts of Artemisia afra Leaves on Brain, Heart and Suprarenal Glands in Swiss Albino Mice.

BACKGROUND: The majority of population rely on traditional medicine as a source of healthcare. Artemisia afra is a plant traditionally used for its medicinal values, including treatment of malaria in many parts of the world. Currently, it is also attracting attention because of a claim that a related species, Artemisia annua, is a remedy for the COVD-19 pandemic. The aim of the present study was to investigate toxic effects of A. afra on brain, heart and suprarenal glands in mice aged 8-12 weeks and weighing 25-30g. METHODS: Leaves of A.afra were collected from Bale National Park, dried under shade, crushed into powder and soaked in distilled water to yield aqueous extract for oral administration. For acute toxicity study, seven treated and one control groups, with 3 female mice each, were used. They were given a single dose of 200mg/kg, 700mg/kg, 1200mg/kg, 2200mg/kg, 3200mg/kg, 4200mg/kg or 5000mg/kg b/wt of the extract. For the sub-acute toxicity study, two treated and one control groups, with 5 female and 5 male mice each, were used. They were daily treated with 600mg/kg or 1800mg/kg b/wt of extract. RESULTS: LD50 was found to be greater than 5000mg/kg indicating that the plant is relatively safe. In the sub-acute study, no signs of toxicity were observed in all treatment groups. On microscopic examination of the brain, heart and suprarenal glands no sign of cellular injury was observed. CONCLUSION: The findings of this study suggest that the leaves extract of A. afra is relatively safe in mice.

Hydride generation coupled with thioglycolic acid coated gold nanoparticles as simple and sensitive headspace colorimetric assay for visual detection of Sb(III).

Antimony (Sb) is a toxic element which causes different health problems including cardiac problems and lung cancer in humans, and its levels in surface water can be noticeably increased to 100 µg/L typically in the proximity of anthropogenic sources. Thus, besides instrumental techniques, it is of great significance to develop a simple, sensitive and selective analytical method for direct analysis of Sb(III) at trace level without the need of any expensive and/or complicated instrumentations and sample preparation processes. Herein, a simple and sensitive headspace colorimetric assay was developed for the detection of Sb(III) by hydride generation coupled with thioglycolic acid functionalized gold nanoparticles (TGA-AuNPs). Sb(III) in the 30 mL sample solution was converted into its volatile form (SbH3) through hydride generation reaction and headspace extracted into 100 µL chromogenic reagent, which contains methanol as extractant and TGA-AuNPs as nanosensors, leading to aggregation of TGA-AuNPs and therefore a red-to-blue color change. Parameters influencing the chromogenic and hydride generation reactions were optimized. Addition of 300 µM ethylenediamine tetraacetic acid (EDTA) as masking agent largely suppressed the inferences from mercury and arsenic. The proposed method can tolerate at least 10-fold As(III) and 100-fold other metal ions including Hg(II). The detection limits were 6.0 and 1.2 µg/L Sb(III) by naked-eye and UV-Vis spectrometer, respectively, which meet the maximum admissible level in drinking water (6 µg/L) set by the United States Environmental Protection Agency. The feasibility of the proposed method was demonstrated by rapid detection of Sb(III) in river water, lake water, ground water and sea water samples by naked-eye at a spiking level of 6 µg/L Sb(III).

Single-drop gold nanoparticles for headspace microextraction and colorimetric assay of mercury (II) in environmental waters.

A novel headspace colorimetric nanosensor strategy for specific detection of Hg(II) was developed based upon analyte induced etching and amalgamation of gold nanoparticles (AuNPs). The Hg(II) was first selectively reduced to its volatile form, Hg(0), by stannous chloride (SnCl2) through chemical cold vapor generation (CVG) reaction. Then, the Hg(0) was headspace extracted into 37µL thioglycolic acid functionalized AuNP aqueous suspension containing 10% methanol as extractant and simultaneously reacted with AuNPs through the strong metallophilic Hg-Au interaction, resulting in a red-to-blue color change. Parameters influencing the chromogenic and chemical vapor generation reactions were optimized. The limit of detections were determined as 5nM through inspection by naked-eye and 1nM based on measurements by UV-Vis spectrometer, which are below the safe limit of Hg(II) in drinking water set by the US Environmental Protection Agency, showing excellent potential for monitoring ultralow levels of Hg(II) in environmental water samples. The assay was not interfered by the presence of other common metal ions even at 1000-fold excess over Hg(II) concentration. The outstanding selectivity results from the combined effect of selective reduction of Hg(II) by SnCl2, efficient separation of sample matrix through headspace extraction, and amalgamation process that occurs specifically between Hg and AuNPs. The method was successfully applied to the visual detection of Hg(II) in environmental water samples at a 10nM spiking level, with recoveries in the range of 86.8-99.8%. More importantly, compared to classical colorimetric assays for detection of Hg(II), this method is featured with simplicity, quite high sensitivity and excellent selectivity. The method is also superior to most colorimetric methods for detection of Hg(II) in terms of its applicability to matrix-rich real samples including wastewater.

Development of reusable magnetic chitosan microspheres adsorbent for selective extraction of trace level silver nanoparticles in environmental waters prior to ICP-MS analysis.

Solid-phase extraction (SPE) based on reusable magnetic chitosan microspheres was coupled with ICP-MS for separation and quantification of silver nanoparticles (AgNPs) in the presence of silver ions in environmental water samples. The monodisperse magnetic chitosan microspheres with an average size of 2µm were engineered using suspension cross-linking technique, and characterized and investigated for its application as SPE adsorbent. Parameters affecting the SPE were optimized, and the best performance was achieved by extracting a 20mL sample (pH 4.5) with 10mg adsorbent for 90min, followed by elution with 1mL 1% (w/v) thiourea in 10% (v/v) nitric acid for 10min. The detection limit, calculated as 3s (s, standard deviation for 11 blank readings), for three AgNPs coated with polyvinyl pyrrolidone (PVP), citrate and polyvinyl alcohol (PVA) and sizes of 31, 40, 46nm, respectively, were in the range of 0.016‒0.023µg/L. The repeatability and reproducibility (RSD, n=7) at a spiking level of 0.1µg/L AgNPs were 4.2% and 8.1%, respectively. The developed method has been applied in the analysis of AgNPs in river, lake and wastewater samples, with excellent extraction efficiencies (84.9‒98.8%) for AgNPs at spiking levels of 0.86 and 8.70µg/L. The cationic chitosan microspheres showed good species selectivity and reusability for extraction of AgNPs in the presence of Ag+, and hence the proposed method is simple, cost effective and environmentally friendly.

Antihypertensive activity of 80% methanol seed extract of Calpurnia aurea (Ait.) Benth. subsp. aurea (Fabaceae) is mediated through calcium antagonism induced vasodilation.

ETHNOPHARMACOLOGICAL RELEVANCE: Calpurnia aurea (Ait.) Benth. subsp. aurea (CASA) (Fabaceae) seeds are used to treat hypertension in Ethiopian folklore medicine, particularly by Shinasha, Agew-awi and Amhara people in northwest Ethiopia. However, the claim has so far not been substantiated scientifically. AIM OF THE STUDY: The study was conducted to evaluate the antihypertensive activity of 80% methanol extract of CASA in animal model of hypertension as well as its vasorelaxant effect and possible underlying mechanisms in isolated guinea pig aorta. MATERIAL AND METHODS: Hypotensive and antihypertensive effect of CASA extract was determined in vivo through the intravenous (iv) route in normotensive and hypertensive anesthetized rats using 2-kidney-1-clip (2K1C) rat model. Ex vivo, guinea pig thoracic aortic rings were isolated and suspended in organ bath, and the vasodepressor effects as well as the mechanism of action of the extract were studied by means of isometric tension recording experiments. RESULTS: The blood pressure fell dose-dependently and significantly in renal hypertensive and normotensive rats following i.v. administration, suggesting that the hydroalcoholic extract possesses hypotensive and antihypertensive effects. The extract also caused a dose-dependent relaxation of aorta pre-contracted with KCl at a concentration of 5-250mg/L, with a maximum relaxation of 92.1% achieved at 250mg/L. The relaxation mechanism was found to be independent of the muscarinic receptors, histamine receptors, ATP dependent K(+) channels, cyclooxygenase enzymes, cGMP/NO pathway and the endothelium system. The extract caused rightward shift of the Ca(++) dose-response curves, similar to that caused by verapamil, indicating that it produced vasorelaxation by inhibiting extracellular Ca(2+) influx. CONCLUSIONS: The findings demonstrate that the plant is endowed with antihypertensive effect, providing evidence for its traditional use. The effect may be, at least in part, due to dilation of blood vessels through blockage of Ca(2+) channels.