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Abstract Background Herbal medicines used for male sexual disorders are widespread across the globe and have been noted as likely candidates for adulteration. To assure access to safe and quality herbal products, this study aimed at sampling some herbal capsules indicated for male vitality for quality analytical checks. Methods Herbal capsules sampled from two regions were subjected to physicochemical assessment, using pharmacopeial and regulatory standards. Microbial quality analysis was also performed on the selected products. A validated HPLC method for simultaneous analysis of sildenafil citrate and tadalafil was used to detect and quantify the possible presence of phosphodiesterase inhibitors in the selected products. Results Out of a total of 57 herbal capsules, 19 were indicated for male sexual related illnesses of which only 8 fulfilled the inclusion criteria of being used exclusively for male vitality. The majority (62.5%) of the herbal products failed the weight uniformity test but all of them disintegrated within the acceptable limit of 30 min. The moisture and heavy metal contents were within limits of acceptability. Majority (87.5%) of the herbal products failed the test for the aerobic bacteria count; however, none of the isolated bacteria was pathogenic. Sildenafil citrate was detected in the majority (87.5%) of the herbal products in concentrations of 0.98–33.95 mg/g. Two products contained both sildenafil and tadalafil. High batch-to-batch variability was recorded in some physicochemical parameters and pharmaceutical adulterants. Conclusion High incidence of quality fails and adulteration of herbal capsules for sexual disorders observed means there is a real risk of unintended dosing with phosphodiesterase inhibitors. This represents a public health issue and necessitates tighter monitoring of production standards by the regulator.

Abstract Background Little is known about the nexus between online gambling and psychological distress among youth, especially in Ghana. This study aimed to investigate the effects of online sports betting on psychological distress, focusing on depression, anxiety, and stress among young individuals in the Volta region of Ghana. Methods A cross-sectional study was carried out at various betting centers in the Volta region of Ghana. Four hundred and three (403) participants were selected using a multi-stage sampling method. The study used a standardized questionnaire to assess psychological distress with the Depression, Anxiety, and Stress Scale (DASS 21) and problematic gambling with the Problem Gambling Severity Index (PGSI). The analysis included both descriptive and inferential methods. These include the implementation of the bootstrap technique within multiple regression models using the current versions of Jeffreys’s Amazing Statistics Program (JASP) [0.18.2], Statistical Package for the Social Sciences (SPSS) [29.0.2], and Microsoft Excel (2019). Results The study found a prevalence of 40% for problematic gambling and 44% for moderate gambling problems among participants, resulting in an overall gambling prevalence of 84%. Regarding psychological distress, the estimated prevalence of depression among participants was 43.6%, with stress reported at 31.1% and anxiety at 68.8%. The overall prevalence of psychological distress was 48%. When analyzing the link between gambling and psychological distress, the study noted that males were more prone to gambling-related psychological distress than females (β = 2.036, p = 0.025). Furthermore, individuals with problem gambling showed the highest probability of experiencing more significant psychological distress compared to other groups (β = 9.228, p = 0.002), followed by those with moderate gambling levels (β = 3.283, p = 0.002). Conclusion We recommend that the mental health unit of the Ghana Health Service, in collaboration with the Gaming Commission of Ghana, should develop youth-friendly interventions to address the prevalence and onset of problematic gambling among the youth, especially males. This could, in turn, reduce the prevalence of psychological distress among youth engaged in online gambling in Ghana.

Faced with challenges like resource depletion and climate change, the cement industry needs sustainable solutions. This study explores the potential of geologically-delinaeated black shale from Apersua, Ghana, as a supplementary cementitious material (SCM) to reduce reliance on traditional methods. The researchers analysed the shale's chemical composition and mineralogy, then created laboratory cement formulations with varying black shale content. These were compared to standard formulations without shale. The results show cement with black shale has comparable compressive strength, meeting standard requirements. Even a formulation with only black shale (excluding limestone, a common ingredient) passed strength tests. Overall, the black shale demonstrated good potential as a SCM based on strength, chemical makeup, setting time, and its possible contribution to durability. This research suggests that black shales from Apersua are worth exploring further as a sustainable and potentially cost-effective alternative in cement production.

Introduction: The demand and consumption of vegetables are significantly increasing worldwide, which has resulted in urban farming on anthropogenic sites. This study assessed the concentrations of some selected heavy metals in lettuce and spring onion in line with the WHO/FAO required standard and its implications on human health. Methods: The study was carried out in Kumasi, within moist semi-deciduous forest vegetation, Ghana. The digested samples were analyzed for heavy metals (Cu, Cr, Fe, Mg, Ni, and Zn) using atomic absorption spectrophotometer (AAS Model AA 400p). Analysis of variance was used to test the level of significance at α = .05. Results: The study found mean concentrations of chromium and iron in lettuce and spring onion to be below detection level (BDL) in all study sites based on WHO/FAO permissible level. Also, while copper in lettuce was BDL at all the sites, there were higher mean concentration of copper in spring onion at BSGS (131.5 ± 0.31 mg/kg) and BSG (120.8 ± 0.01 mg/kg). The mean concentration of nickel in lettuce (137.15 ± 0.0231) and spring onion (173.55 ± 0.02 mg/kg) at BSGS were higher than WHO/FAO permissible level. Mean concentration of zinc in both lettuce and spring onion were higher than WHO/FAO permissible level in all the study sites, except zinc in spring onion at KT. The ANOVA test statistics showed no significant difference among the concentrations of heavy metals in all sites, except zinc in lettuce and nickel in spring onion. The study found cancer risk factor for nickel, which exceeded the benchmark of 1 × 10 −6 for both lettuce and spring onion, indicating that long-term consumption could increase the risk of cancer in consumers. Conclusion: The study’s findings call for strict regulation and regular monitoring of heavy metals in vegetables cultivated at anthropogenic sites in urban areas to ensure food safety and consumer health.

Various parts of the plant, Sterculia setigera Delile, from the Malvaceae family are largely used in most African countries for medicinal purposes. In African traditional medicine, the plant is used to treat fever, bacterial infection, diarrhoea, epilepsy, anaemia, and hypertension. Due to its high therapeutic properties, it has become a highly sought-after plant by researchers for pharmacological properties aimed at validating or providing scientific backing for its traditional use. Additionally, efforts to obtain small natural molecules from the plant as scaffolds for the development of new drugs have been explored. Although it is extensively used in traditional medicine and its phytochemical composition and biological activity are widely studied, there is no review paper that systematically analyses its biological activities and phytochemical composition. Hence, this review provides a systematic overview of the biological activities, phytochemical constituents, and ethnomedicinal properties of the plant. The data show S. setigera is a promising medicinal plant with pharmacological potential and thus can be useful for the development of novel therapeutic agents.

Background: Many countries undertake development activities that utilize resources from the environment. In the Democratic Republic of the Congo (DRC), the Congolese Environmental Agency is supervised by the Ministry of Environment and Sustainable Development to undertake an environmental assessment of all projects that pose risks to the environment. The present study conducted a critical review of the country’s existing environmental assessment legislation, identifying strengths and weaknesses in the Environmental and Social Impact Assessment (ESIA) system. Methods: A literature survey was done in the Google Scholar, Taylor & Francis, and Elsevier databases, which were also guided by the PRISMA. All full-text articles included in the study were written or translated (using online translation software) into the English language, and also, reported on environmental impact assessment as well as legislation. A textual examination of the included literature was done. A set of adapted analytical criteria was used to critically review the ESIA system in the DRC. The results were discussed, and recommendations were given. Results: It was found that the decree was not effective and efficient for the ESIA study. Some of the key limitations of the ESIA decree included the lack of scoping in the entire ESIA process, alternatives that were limited in scope, fees and charges that were not explicitly stated in the legislation, and the lack of public participation at some stages. Conclusion: The ESIA system in the DRC is ineffective and needs revision to improve its effectiveness.

Background Globally, one of the measures of high performing healthcare facilities is the compliance of patient safety culture, which encompasses the ability of health institutions to avoid or drastically reduce patient harm or risks. These risks or harm is linked with numerous adverse patient outcomes such as medication error, infections, unsafe surgery and diagnosis error.Objectives The general objective of this study was to investigate into the impact of patient safety culture practices experienced on patient satisfaction among patients who attend the Kwesimintsim Government Hospital in the Takoradi municipality.Methods This study was a descriptive cross-sectional study and a consecutive sampling technique was used to select 336 respondents for the study. Data was collected using a structured questionnaire and processed using Statistical Package for Social Sciences, V.21. Both descriptive and inferential statistics were carried out and result were presented using figures and tables.Results The study found that the overall patient safety compliance level observed by the respondents was poor (29.2%). The prevalence of adverse events experienced among the respondents was high (58%). The leading adverse events mentioned were medication errors, followed by wrong prescriptions and infections. The consequences of these adverse events encountered by the respondents were mentioned as increased healthcare costs (52%), followed by hospitalisation (43%), worsening of health conditions (41%) and contraction of chronic health conditions (22%). Patient safety cultural practices such as teamwork (β=0.17, p=0.03), response to error (β=0.16, p=0.005), communication openness (β=0.17, p=0.003) and handoffs and information exchange (β=0.17, p=0.002) were found to positively influence patient satisfaction.Conclusion The poor general compliance of the patient safety culture in the facility is unfortunate, and this can affect healthcare outcomes significantly. The study therefore entreats facility managers and various stakeholders to see patient safety care as an imperative approach to delivering quality essential healthcare and to act accordingly to create an environment that supports it.

Natural products have a long history of use in the treatment of various diseases particularly in developing countries. The use of compounds of natural origin as lead compounds for the development of conventional drugs is widely recognised. Natural product-based drug discovery efforts in developing countries mostly involve the use of crude extracts in in-vitro and/or in-vivo assays. There are limited efforts at isolating active principles for structure elucidation studies. Studies that isolate pure secondary metabolites and characterize their structures have limited bioactivity evaluations. In conventional drug discovery programs, molecular docking serves as a useful tool for predicting interactions of small molecules with drug target(s) to guide synthesis decisions. Medicinal chemists use this tool to predict and synthesize compounds likely to have pharmacological activity and thus save time and cost for drug discovery. Efforts have been made to incorporate molecular docking techniques into natural products-based drug discovery. The objective of this review is to discuss molecular docking in natural product drug discovery programs with the goal of providing easy-to-understand information to help beginners interested in incorporating molecular docking in their research. This is expected to enhance natural product screening programs by predicting which phytochemicals are likely to show success, especially in new disease situations such as COVID-19. Applications in the repositioning of plants for emerging conditions are also discussed.

Background: The emergence of widespread drug-resistant strains of the malaria parasites militates against strives for more potent antimalarial drugs. Aim: The present study evaluated the antimalarial activity of A. africana ethanolic crude extract in vitro and in vivo against Plasmodium berghei -infected mice in anticipation of acquiring scientific evidence for it used by mangrove dwellers to treat malaria in Ghana. Methodology: The pulverized dried leaves were extracted with 70% ethanol (v/v) and screened for phytochemicals using standard protocols. The in vitro antimalarial activity was investigated against chloroquine-sensitive Plasmodium falciparum (Pf3D7 clones), MRA-102, Lot:70032033, via SYBR® Green I fluorescent assay method using positive control Artesunate (50–1.56 × 10−3 μg/mL). In the in vivo studies, doses (200–1500 mg/kg) of AAE were used in the 4-day suppressive and curative tests, using P. berghei-infected mice. Artemether/lumefantrine (1.14 mg/kg) and normal saline were used as positive and negative control respectively. Results: The phytochemical analysis revealed the presence of alkaloids, saponins, flavonoids, glycosides, tannins, terpenoids and phytosterols. The extract showed an IC50 of 49.30 ± 4.40 μg/mL in vitro and demonstrated complete parasite clearance at dose 1500 mg/kg in vivo with a suppressive activity of 100% (p 5000 mg/kg in mice. Conclusion: The results demonstrated that A. africana crude extract has antimalarial activity both in vitro and in vivo supporting the traditional use of the plant to treat malaria.

Ziziphus abyssinica root bark is widely used in folk medicine to manage liver diseases, particularly, jaundice but its effect on paracetamol-induced liver toxicity (PILT) has not yet been validated. This study explored the ameliorative effect of ethanolic root bark extract of Ziziphus abyssinica (ZAE) against PILT in rats. The flavonoid and phenolic content of ZAE was evaluated using Folin-Ciocalteau and aluminium trichloride colorimetric methods, respectively. Antioxidant activity of ZAE was determined in vitro by evaluating its ferrous reducing antioxidant capacity (FRAC) as well as DPPH and nitic oxide (NO) radicals scavenging activities. Sprague-Dawley rats were assigned to six groups (n = 6) and administered with normal saline (10 mL/kg, p.o.), N-acetylcysteine (50 mg/kg, i.p.) and ZAE (30, 100, and 300 mg/kg, p.o.) respectively for seven days after which they received paracetamol (PCM, 3000 mg/kg, p.o.). Animals were sacrificed 48 h after paracetamol administration under light anaesthesia and assessed for liver toxicity and oxidative stress. Total flavonoid and phenolic contents of ZAE were 1313.425 µg/mL quercetin equivalence and 268.31 µg/mL gallic acid equivalence respectively. ZAE exhibited marked FRAC as well as DPPH and NO radical scavenging activities with IC50s of 80.41 ± 1.56, 67.56 ± 1.11 and 7.11 ± 1.48 μg/mL respectively. ZAE and N-acetylcysteine significantly (p

Objectives This study estimates the prevalence of self-medication and provides an understanding of the reasons for self-medication in Ghana through the synthesis of relevant literature.Methods A comprehensive search was conducted in PubMed, Science Direct and African Journals Online to identify observational studies published from inception to March 2022. Google scholar and institutional websites were searched for grey literature. We included studies reporting primary data on the prevalence and/or reasons for self-medication in Ghana. Random-effects meta-analysis was used to estimate the prevalence of self-medication. Subgroup analysis was performed with the study population (pregnant women, patients and students), geopolitical zone (coastal, middle and northern) and study setting (rural and urban). Using inductive thematic analysis, reasons for self-medication were classified and tallied under key themes.Results Thirty studies involving 9271 participants were included in this review. The pooled prevalence of self-medication in Ghana was 53.7% (95% CI 46.2% to 61.0%; I²=98.51%, p

IntroductionLesbian, gay, bisexual, transgender, and intersex (LGBTI) and related activities have been a topic of debate and discussion among policymakers and stakeholders, as well as common citizens in the African region, especially in Ghana. The current anti-LGBTI-related bill being put before Ghana's Parliament signifies the intensity of the issue. Even though some studies have looked at some aspects of the issue, no study presently has explored people's opinion on the passage of any future anti-LGBTI and related legislations in Ghana.AimThis study examined the perspective of tertiary-level students on the passage of anti-LGBTI legislation, as well as the non-physical factors that influence support for the passage of anti-LGBTI and related legislation in Ghana.MethodsThe study employed a quantitative cross-sectional design using 1,001 tertiary-level students. The study used convenience sampling technique with an online closed-ended, structured survey questionnaire as the main data collection instrument. The data was then analysed using Statistical Package for the Social Sciences, version 29 at a 5% significance level.ResultsThe results of the study indicated that majority of the respondents (81%) were in support of the passage of anti-LGBTI and related legislations. Their reasons included the health implications of LGBTI and related activities (63%), cultural and societal values (62%), religious reasons (54%), and western culture (25%). Also, almost half of the respondents (49%) held that health related perceptions about LGBTI have little or no empirical basis. The inferential analysis, further, revealed that even when age and sex assigned at birth are controlled, perceived health implications of LGBTI (β = 0.247, p = < .001), religious beliefs (β = 0.189, p = < .001), and cultural values (β = 0.218, p = < .001) positively predict the support for passage of anti-LGBTI legislation.ConclusionsPeople's level of support for the passage of anti-LGBTI legislation is influenced by several factors including religious beliefs, cultural values, and the perceived health implications of LGBTI. There is, however, the need for policy makers and other stakeholders to create awareness and educate the public about the various perceptions about LGBTI and related activities that are not scientifically legitimate.

This study focused on documenting and evaluating the cercaricidal activity of medicinal plants used for schistosomiasis treatment in an endemic area in Ghana. Through semistructured questionnaires, personal interviews with herbalists in communities surrounding the Barekese dam in the Atwima-Nwabiagya district, where the disease is endemic, were carried out. Thirty medicinal plants distributed in 19 families were reported to be used for schistosomiasis treatment in the survey. Information on the plants, including scientific names, common names, families, and the used plant part were recorded. The families Apocynaceae and Euphorbiaceae recorded the highest number of plants (14% each), followed by Asteraceae (10%), Loranthaceae (7%), and Rubiaceae (7%). In vitro cercaricidal activity of methanol extracts of nine out of the thirty plants was performed by exposing human Schistosoma mansoni cercariae obtained from Biomphalaria pfeifferi to various concentrations of extracts over a duration of 240 minutes. All the plants tested demonstrated time- and concentration-dependent cercaricidal activity. With lethality being set at Balanites aegyptiaca (LC50 = 7.1) > Xylia evansii (LC50 = 11.14) > Jathropha multifida (LC50 = 12.9) > Justicia flava (LC50 = 22.9) > Anopyxis klaineana (LC50 = 182.81) > Ximenia americana (LC50 = 194.98) > Loranthus lecardii (LC50 = 223.87) > Bridelia tenufolia (LC50 = 309.03) > Zanthoxylium zanthoxyloides (LC50 = 851.94). Phytochemicals, including alkaloids, tannins, triterpenes, saponins, phytosterols, and flavonoids were identified in the plants. The result of this study gives scientific credence to the traditional use of these plants in the treatment of schistosomiasis and proves that the rich botanical knowledge of medicinal plants provides an incredible starting point for the discovery of new anti-schistosomal drugs for the local population.

The leaves of Manihot esculenta Crantz are used widely in traditional medicine to treat gastric ulcers. However, the safety and ethnopharmacological use of the plant as an anti-ulcer agent has not been validated in experimental studies. The study investigated the toxicity profile and anti-ulcer properties of ethanolic leaf extract of Manihot esculenta (MELE) in rats. A high dose of MELE (2000 mg/kg, p.o.) did not cause death in any of the rats. Moreover, no behavioural, haematological, or biochemical abnormalities could be attributed to the extract. The administration of acidified alcohol reduced rats’ luminal pH from 4.47 ± 1.39 (naïve control) to 1.95 ± 0.31 in the negative control rats. However, pre-treatment of rats with MELE (30, 100, and 300 mg/kg, p.o.) or omeprazole (10 mg/kg, p.o.) significantly (p < 0.05) elevated the luminal pH to 2.24 ± 0.19, 3.21 ± 0.18, 3.12 ± 0.40 and 2.63 ± 0.10 respectively. MELE (100 and 300 mg/kg) and omeprazole (10 mg/kg) caused a significant (p < 0.05) reduction in rats’ gastric ulceration with percentage inhibition of 71.05, 76.31 and 78.94% respectively. The extensive ulceration and erosion of the stomachs of rats in the negative control group were reversed by treatment with various doses of the extract and omeprazole. Elevated Ki67 immunoreactivity in the negative control group was also reduced by the MELE (30, 100 and 300 mg/kg) and the standard reference drug, omeprazole (10 mg/kg). The present study suggests that MELE produced no observed adverse effects and offered protection against acidified ethanol-induced gastric ulceration. Further studies should aim at isolating the active compounds responsible for the anti-ulcer effect as well as their possible mechanisms of action.

Abstract Background The adulticidal and cercaricidal activities of five Ghanaian medicinal plants, namely, Phyllanthus amarus, Vernonia amygdalina, Azadirachta indica, Morinda lucida and Nauclea latifolia against S. mansoni were evaluated in this study. Six weeks old ICR mice (n = 25) were percutaneously infected with S. mansoni cercariae. Nine weeks later, infected mice (n = 5) were anaesthetised and perfused for adult S. mansoni. Cercariae were treated with different concentrations (1000, 500, 250, 125, 62.5, 31.25 μg/mL) of methanolic extracts of the experimenting plants in triplicates. Adult S. mansoni incopula were also treated with same concentrations of each extract or 20 μg/mL praziquantel. The cercariae and adult worms were observed at time intervals for 180 min and 120 h to assess mortality and viability respectively. Additionally, 9-week cercariae-infected mice (4 groups of 5 mice) were treated with either 500 mg/kg po A. indica or V. amygdalina, 400 mg/kg po praziquantel or distilled water for 14 days. The mice were euthanized after adult worms were recovered from them. The liver was processed and histologically examined for granuloma formations. Results All the plants exhibited varying cercaricidal and adulticidal activities against S. mansoni in a time and concentration-dependent manner. A. indica (3 h IC50 = 27.62 μg/mL) and V. amygdalina (3 h IC50 = 35.84 μg/mL) exerted the highest cercaricidal activity. Worm recovery after treatment with V. amygdalina, A. indica and praziquantel in vivo was 48.8%, 85.1 % and 59.9 % respectively (p < 0.05). A. indica and V. amydalina-treated mice recorded lesser mean liver and spleen weights compared to untreated groups (p < 0.05). Conclusion A. indica demonstrated the highest cercaricidal and alduticidal activities in vitro, whereas V. amygdalina exhibited the most potent aldulticidal activity in vivo. This study could provide baseline information which can be used to develop plant-based alternative commercial drugs against S. mansoni.

Background: Zingiber officinale Roscoe (ginger) rhizome is a global spice with marked pharmacological activities and industrial applications. The demand for the powdered spice soared in the wake of the COVID-19 global pandemic. The present study sought to assess powdered ginger products on the Ghanaian market for some quality parameters and compare their chemical composition via chemometric analysis of their FT-IR data. Methods: A survey was conducted in three major markets in Ghana to determine the commercially available powdered ginger products. These products were purchased and assessed for microbial load, heavy metals contents and ash values using official methods. Also, principal component and hierarchical cluster analysis, as multivariate algorithms, were applied to their FT-IR spectral fingerprints, using Z. officinale, Z. zerumbet and some dried ginger rhizomes from Nigeria as reference samples. Results: Seven products were found in the survey: three local and four foreign. The local products failed to meet regulatory label requirements. The microbial load, heavy metals and ash values of all commercial samples were generally within specifications except for the aerobic bacterial counts of some local samples. Pharmacopoeial identity test and the chemometric analysis revealed all the products to contain Z. officinale. The reference ginger sample from Nigeria also demonstrated some level of similarity with Z. officinale. The variations in physical attributes and slight difference in chemical composition of the different products was presumed to be due to chemical changes arising from different processing methods and possible adulteration with other flours. Conclusion: The sampled ginger products on the market originate from Z. officinale and have quality attributes that make them suitable for food and medicinal applications. The observed deviations, however, suggest an urgent need for standardized processing methods to ensure consistency in quality indices, as well as regular quality checks by regulatory bodies.

Avicennia africana is an important ethnomedicinal plant that has long been used to treat malaria and several other diseases. Despite the plant’s antimalarial and other therapeutic properties, there is limited evidence-based data on its potential toxicity. Hence, the purpose of the current study was to assess the safety of A. africana leaf ethanolic extract (AAE). The study was designed to ascertain the cytotoxic effects of the crude extract on red blood cells (RBCs) as well as the acute and subacute toxicity in Wistar albino rats in accordance with Organization for Economic Co-operation and Development (OECD) guidelines “Test No. 423” and CPMW/SWP/1042/99. The pulverized, shade-dried plant leaves were sequentially macerated with 70% ethanol to obtain the crude extract (AAE). The extract’s cytotoxic activity (CC50) against the uninfected human red blood cells (RBCs) was determined using the 3-(4,5-Dimethylythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. For the acute toxicity studies, the rats (male and female) were divided randomly into six groups of five rats (n = 5) and dosed orally once with the following dose levels: 100, 300, 1000, 3000, and 5000 mgkg−1, p.o. of the extracted AAE, with the control group receiving only the vehicle. In the repeated dose toxicity studies, the rats (both sexes) were orally administered daily with AAE at 100, 300, and 1000 mgkg−1 for 14 days. Rat body weights were measured, and blood samples were tested for haematological and biochemical markers. Internal organs like the heart, kidney, liver, and spleen were collected, inspected, and weighed, and histological examinations were performed. The median lethal dose (LD50) value is greater than 5000 mgkg−1 body weight, with no significant change in bodyweight or relative organ weight (ROWs) of the extract-treated groups or control group. The extract showed greater cytotoxicity activity (CC50), which was >100 μg/mL, compared to the reference drug (artesunate).The dosage groups of 100 and 300 mgkg−1 bwt had neutrophilia and lymphocytopenia (p0.05). Histopathological examination of internal organs of AAE-treated rats did not show any significant abnormalities resulting from the extract treatment compared to the control group. Based on the findings in the present study, the LD50 value of AAE was found to exceed 5000 mgkg−1 in the acute toxicity test, while the no observed adverse effect level (NOAEL) in rats was 1000 mgkg−1 p.o. In the sub-acute toxicity tests. Histopathological analysis revealed no morphological abnormalities in the vital organs.

Buruli ulcer disease, a necrotising skin and subcutaneous tissue disease, is endemic to tropical Africa. People in endemic communities’ resort to topical and oral consumption of plant extracts which have not been validated. The present study focused on validating the antimycobacterial properties and toxicity of different solvent extracts of the stem bark of P. angolensis and establish pharmacognostic standards for quality control purposes. In vitro antimycobacterial activity of the aqueous, 70% hydro-ethanol and ethyl acetate stem bark extracts of P. angolensis against M. ulcerans (NM 203 strain) was done using the Resazurin Microtiter Assay and their cytotoxicity assessed on normal Chang liver cells via the Alamar Blue assay. Pharmacognostic parameters were also evaluated according to standard methods. The ethyl acetate extract of the stem bark showed considerable activity against the M. ulcerans (MIC = 256 µg/mL) but was less active than the reference drugs streptomycin (MIC = 0.25 µg/mL) and rifampicin (MIC = 0.125 µg/mL). The aqueous and hydroethanolic extracts showed no activity. The active ethyl acetate extract was not cytotoxic (CC50=383.9 ± 69.7 µg/mL). Micromorphological analysis of the leaf surface revealed stellate trichomes and schizogenous cavities. Stem bark powder microscopy showed abundant starch grains, prismatic calcium oxalate crystals and large striated stone cells with a wide lumen. Morphological features, physicochemical, chromatographic, and spectroscopic standards have been established to guarantee consistency in the quality of herbal products containing P. angolensis. The activity of P. angolensis extract against M. ulcerans substantiates the traditional use of P. angolensis stem bark for Buruli ulcer management and as a potential source of antimycobacterial agents.

The diversity offered by natural products has timelessly positioned them as a good source for novel therapeutics for the management of diverse medical conditions, including pain. This study evaluated hydro-ethanolic root bark extract of Ziziphus abyssinica (ZAE) as well as β-amyrin and polpunonic acid isolated from the plant for analgesic property. The study also investigated the mechanism responsible for this action in the extract. The antinociceptive potential of ZAE (30, 100, and 300 mg/kg, p. o.) was assessed using the tail-immersion test (TIT), acetic acid-induced writhing test (AAT), and formalin test (FT). The extract’s effect on acute and chronic musculoskeletal pain was also assessed by administering carrageenan unilaterally into the rat gastrocnemius muscles and measuring pain at 12 h and 10 days for acute and chronic pain respectively. The involvement of pro-inflammatory mediators (prostaglandin E2, bradykinin, TNF-α, and IL-1β) was assessed. The possible pathways mediating the observed analgesic effect of ZAE were further assessed using the antagonists: naloxone, glibenclamide, NG-L-nitro-arginine methyl ester (L-NAME), atropine, nifedipine, and yohimbine in the FT. Also the analgesic effect of two triterpenoid compounds, β-amyrin and polpunonic acid, previously isolated from the plant was assessed using the TIT. The anti-nociceptive activity of ZAE was demonstrated in the TIT by the significant (p < 0.05) increase in tail withdrawal threshold in ZAE-treated mice. ZAE also markedly reduced writhing and paw licking responses in both AAT and FT and significantly (p < 0.05) attenuated both acute and chronic musculoskeletal pain. ZAE also significantly reversed hyperalgesia induced by intraplantar injection of PGE2, bradykinin, TNF-α, and IL-1β. Furthermore, data revealed the involvement of opioidergic, ATP-sensitive K+ channels and NO-cGMP pathways in the analgesic effect of ZAE. Both β-amyrin and polpunonic acid exhibited analgesic activity in the tail suspension test. Our study demonstrates ZAE as an important source of new therapeutic agents for pain management.

The majority of indigenes in the rural areas of Ghana use herbal medicines for their primary health care. In this study, an ethnobotanical survey was undertaken to document medicinal plants used by traditional healers in the Ejisu-Juaben district in the Ashanti region of Ghana to treat infections and to further investigate the antibiofilm formation properties of selected plants in resisting pathogenic bacteria. Seventy medicinal plants used by traditional practitioners for the treatment of skin infections and wounds were documented from the ethnobotanical survey. Forty out of the seventy plants were collected and their methanol extracts evaluated for antimicrobial activity by the agar diffusion assay. Extracts that showed antibacterial activity were tested for biofilm inhibitory activity, and the most active plant was subsequently purified to obtain the active constituents. Biofilm formation was significantly mitigated by petroleum ether, ethyl acetate, and methanol extracts of Holarrhena floribunda stem bark. Bioassay-guided fractionation of an alkaloidal extract prepared from the methanol fraction led to the isolation of three steroidal alkaloids, namely, holonamine, holadienine, and conessine. The isolated compounds demonstrated varying degrees of biofilm formation inhibitory properties. The current study reveals that screening of indigenous medicinal plants could unravel potential leads to salvage the declining efficacy of conventional antibiotics. Holarrhena floribunda stem bark extract has strong biofilm formation inhibition properties, which could be attributed to the presence of steroidal alkaloids.

Abstract Background Every curriculum needs to be reviewed, implemented and evaluated; it must also comply with the regulatory standards. This report demonstrates the value of curriculum mapping (CM), which shows the spatial relationships of a curriculum, in developing and managing an integrated medical curriculum. Methods A new medical school developed a clinical presentation driven integrated curriculum that incorporates the active-learning pedagogical practices of many educational institutions worldwide while adhering to the mandated requirements of the accreditation bodies. A centralized CM process was run in parallel as the curriculum was being developed. A searchable database, created after the CM data was uploaded into an electronic curriculum management system, was used to ensure placing, integrating, evaluating and revising the curricular content appropriately. Results CM facilitated in a) appraising the content integration, b) identifying gaps and redundancies, c) linking learning outcomes across all educational levels (i.e. session to course to program), c) organizing the teaching schedules, instruction methods, and assessment tools and d) documenting compliance with accreditation standards. Conclusions CM is an essential tool to develop, review, improve and refine any integrated curriculum however complex. Our experience, with appropriate modifications, should help other medical schools efficiently manage their curricula and fulfill the accreditation requirements at the same time.

(1) Background: Military combat impacts the mental health of veterans and active military personnel. Although various studies, the majority of which are from Westernized countries, have provided insight into how combat causes psychiatric disorders, such as post-traumatic stress disorder (PTSD), depression, and anxiety among veterans, there appears to be scant published literature on psychiatric disorders among military personnel in the West African region. It is important to contextually understand the psychiatric disorders among military personnel in this region who may be faced with similar vulnerabilities to their counterparts from Western cultures. (2) Methods: This study follows the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Studies were included if they were published in English between January 2010 and January 2021 and assessed mental health problems or psychiatric disorders among soldiers in West Africa. (3) Results: All three included studies were from Nigeria. High prevalence rates of substance and alcohol use were reported. (4) Conclusions: This review highlights the need for more research in this population as well as identifying the intervention needs of the soldiers and their implications.

Objective: To investigate the effect of pre-existing Schistosoma haematobium (S. haematobium) infection on malaria disease severity. Methods: The study involved the use of twenty-five imprinting control region mice, fifteen of which were initially infected with S. haematobium. Five of the remaining ten schisto-uninfected mice together with five schisto-infected mice were infected with Plasmodium berghei (P. berghei) after four weeks (acute stage) of schistosoma infection. The remaining five schisto-uninfected mice together with five schisto-infected mice were also infected with P. berghei after seven weeks (chronic stage) of schistosoma infection. The last five schisto-infected mice were used as control group. They were then monitored for changes in P. berghei parasitaemia on Days 3, 5, 7, 9 and 11 post-infection. Records on their survivability were also taken. Results: The co-infected mice had significantly higher malaria parasitaemia, compared with the mono-infected mice during acute S. haematobium infection. In contrast, the co-infected mice had significantly lower malaria parasitaemia during chronic S. haematobium infection and a higher survival rate. Conclusions: Co-infection of mice with P. berghei during acute S. haematobium infection resulted in rapid P. berghei development and increased malaria parasitaemia. However, the co-infection resulted in slower P. berghei development and decreased malaria parasitaemia with enhanced survivability of the mice during chronic S. haematobium infection. Therefore, pre-existing chronic S. haematobium infection may provide some protection to the host by reducing parasitaemia.

Bull.Chem.Soc.Ethiop., 2(2), 73-78 (1988).

Lenacapavir (LEN) is a highly potent, long-acting antiretroviral medication for treating people infected with muti-drug-resistant HIV-1 phenotypes. The inhibitor targets multifaceted functions of the viral capsid protein (CA) during HIV-1 replication. Previous studies have mainly focused on elucidating LEN's mode of action during viral ingress. Additionally, the inhibitor has been shown to interfere with mature capsid assembly during viral egress. However, the mechanism for how LEN affects HIV-1 maturation is unknown. Here, we show that pharmacologically relevant LEN concentrations do not impair proteolytic processing of Gag in virions. Instead, we have elucidated the primary mechanism for highly potent inhibition of HIV-1 maturation by sub-stoichiometric LEN:CA ratios. The inhibitor exerts opposing effects on formation of CA pentamers versus hexamers, the key capsomere intermediates in mature capsid assembly. LEN impairs formation of pentamers, whereas it induces assembly of hexameric lattices by imposing an opened CA conformation and stabilizing a dimeric form of CA. Consequently, LEN treatment results in morphologically atypical virus particles containing malformed, hyper-stable CA assemblies, which fail to infect target cells. Moreover, we have uncovered an inverse correlation between inhibitor potency and CA levels in cell culture assays, which accounts for LEN's ability to potently (with pM EC 50 values) inhibit HIV-1 maturation at clinically relevant drug concentrations., Author Summary: Lenacapavir (LEN) is the first-in-class HIV-1 capsid targeting antiretroviral that exhibits multimodal modality to inhibit both early and late steps of viral replication. Our studies here have elucidated previously undescribed structural and mechanistic bases for a highly potent antiviral activity of LEN during viral egress. These findings will inform clinical applications of LEN as a potent HIV-1 maturation inhibitor and aid the development of second-generation inhibitors targeting assembly of the mature viral capsid.

Lenacapavir (LEN) is the first in class viral capsid protein (CA) targeting antiretroviral for treating multi-drug-resistant HIV-1 infection. Clinical trials and cell culture experiments have identified resistance associated mutations (RAMs) in the vicinity of the hydrophobic CA pocket targeted by LEN. The M66I substitution conferred by far the highest level of resistance to the inhibitor compared to other RAMs. Here we investigated structural and mechanistic bases for how the M66I change affects LEN binding to CA and viral replication. The high-resolution X-ray structure of the CA(M66I) hexamer revealed that the β-branched side chain of Ile66 induces steric hindrance specifically to LEN thereby markedly reducing the inhibitor binding affinity. By contrast, the M66I substitution did not affect binding of Phe-Gly (FG)-motif-containing cellular cofactors CPSF6, NUP153, or SEC24C, which engage the same hydrophobic pocket of CA. In cell culture the M66I variant did not acquire compensatory mutations or replicate in the presence of LEN. Analysis of viral replication intermediates revealed that HIV-1 (M66I CA) predominantly formed correctly matured viral cores, which were more stable than their wildtype counterparts. The mutant cores stably bound to the nuclear envelope but failed to penetrate inside the nucleus. Furthermore, the M66I substitution markedly altered HIV-1 integration targeting. Taken together, our findings elucidate mechanistic insights for how the M66I change confers remarkable resistance to LEN and affects HIV-1 replication. Moreover, our structural findings provide powerful means for future medicinal chemistry efforts to rationally develop second generation inhibitors with a higher barrier to resistance., Importance: Lenacapavir (LEN) is a highly potent and long-acting antiretroviral that works by a unique mechanism of targeting the viral capsid protein. The inhibitor is used in combination with other antiretrovirals to treat multi-drug-resistant HIV-1 infection in heavily treatment-experienced adults. Furthermore, LEN is in clinical trials for preexposure prophylaxis (PrEP) with interim results indicating 100 % efficacy to prevent HIV-1 infections. However, one notable shortcoming is a relatively low barrier of viral resistance to LEN. Clinical trials and cell culture experiments identified emergent resistance mutations near the inhibitor binding site on capsid. The M66I variant was the most prevalent capsid substitution identified in patients receiving LEN to treat muti-drug resistant HIV-1 infections. The studies described here elucidate the underlying mechanism by which the M66I substitution confers a marked resistance to the inhibitor. Furthermore, our structural findings will aid future efforts to develop the next generation of capsid inhibitors with enhanced barriers to resistance.

HIV-1 integration favors nuclear speckle (NS)-proximal chromatin and viral infection induces the formation of capsid-dependent CPSF6 condensates that colocalize with nuclear speckles (NSs). Although CPSF6 displays liquid-liquid phase separation (LLPS) activity in vitro, the contributions of its different intrinsically disordered regions, which includes a central prion-like domain (PrLD) with capsid binding FG motif and C-terminal mixed-charge domain (MCD), to LLPS activity and to HIV-1 infection remain unclear. Herein, we determined that the PrLD and MCD both contribute to CPSF6 LLPS activity in vitro. Akin to FG mutant CPSF6, infection of cells expressing MCD-deleted CPSF6 uncharacteristically arrested at the nuclear rim. While heterologous MCDs effectively substituted for CPSF6 MCD function during HIV-1 infection, Arg-Ser domains from related SR proteins were largely ineffective. While MCD-deleted and wildtype CPSF6 proteins displayed similar capsid binding affinities, the MCD imparted LLPS-dependent higher-order binding and co-aggregation with capsids in vitro and in cellulo. NS depletion reduced CPSF6 puncta formation without significantly affecting integration into NS-proximal chromatin, and appending the MCD onto a heterologous capsid binding protein partially restored virus nuclear penetration and integration targeting in CPSF6 knockout cells. We conclude that MCD-dependent CPSF6 condensation with capsids underlies post-nuclear incursion for viral DNA integration and HIV-1 pathogenesis., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

HIV-1 infection requires passage of the viral core through the nuclear pore of the cell, a process that depends on functions of the viral capsid. Recent studies have shown that HIV-1 cores enter the nucleus prior to capsid disassembly. Interactions of the viral capsid with the nuclear pore complex are necessary but not sufficient for nuclear entry, and the mechanism by which the viral core traverses the comparably sized nuclear pore is unknown. Here we show that the HIV-1 core is highly elastic and that this property is linked to nuclear entry and infectivity. Using atomic force microscopy-based approaches, we found that purified wild type cores rapidly returned to their normal conical morphology following a severe compression. Results from independently performed molecular dynamic simulations of the mature HIV-1 capsid also revealed its elastic property. Analysis of four HIV-1 capsid mutants that exhibit impaired nuclear entry revealed that the mutant viral cores are brittle. Adaptation of two of the mutant viruses in cell culture resulted in additional substitutions that restored elasticity and rescued infectivity and nuclear entry. We also show that capsid-targeting compound PF74 and the antiviral drug Lenacapavir reduce core elasticity and block HIV-1 nuclear entry at concentrations that preserve interactions between the viral core and the nuclear envelope. Our results indicate that elasticity is a fundamental property of the HIV-1 core that enables nuclear entry, thereby facilitating infection. These results provide new insights into the role of the capsid in HIV-1 nuclear entry and the antiviral mechanisms of HIV-1 capsid inhibitors., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Deshpande et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

HIV-1 capsid (CA) stability is important for viral replication. E45A and P38A mutations enhance and reduce core stability, thus impairing infectivity. Second-site mutations R132T and T216I rescue infectivity. Capsid lattice stability was studied by solving seven crystal structures (in native background), including P38A, P38A/T216I, E45A, E45A/R132T CA, using molecular dynamics simulations of lattices, cryo-electron microscopy of assemblies, time-resolved imaging of uncoating, biophysical and biochemical characterization of assembly and stability. We report pronounced and subtle, short- and long-range rearrangements: (1) A38 destabilized hexamers by loosening interactions between flanking CA protomers in P38A but not P38A/T216I structures. (2) Two E45A structures showed unexpected stabilizing CA NTD -CA NTD inter-hexamer interactions, variable R18-ring pore sizes, and flipped N-terminal β-hairpin. (3) Altered conformations of E45A a α9-helices compared to WT, E45A/R132T, WT PF74 , WT Nup153 , and WT CPSF6 decreased PF74, CPSF6, and Nup153 binding, and was reversed in E45A/R132T. (4) An environmentally sensitive electrostatic repulsion between E45 and D51 affected lattice stability, flexibility, ion and water permeabilities, electrostatics, and recognition of host factors., (© 2023. Springer Nature Limited.)

Cellular proteins CPSF6, NUP153 and SEC24C play crucial roles in HIV-1 infection. While weak interactions of short phenylalanine-glycine (FG) containing peptides with isolated capsid hexamers have been characterized, how these cellular factors functionally engage with biologically relevant mature HIV-1 capsid lattices is unknown. Here we show that prion-like low complexity regions (LCRs) enable avid CPSF6, NUP153 and SEC24C binding to capsid lattices. Structural studies revealed that multivalent CPSF6 assembly is mediated by LCR-LCR interactions, which are templated by binding of CPSF6 FG peptides to a subset of hydrophobic capsid pockets positioned along adjoining hexamers. In infected cells, avid CPSF6 LCR-mediated binding to HIV-1 cores is essential for functional virus-host interactions. The investigational drug lenacapavir accesses unoccupied hydrophobic pockets in the complex to potently impair HIV-1 inside the nucleus without displacing the tightly bound cellular cofactor from virus cores. These results establish previously undescribed mechanisms of virus-host interactions and antiviral action., (© 2022. The Author(s).)

In infectious HIV-1 particles, the capsid protein (CA) forms a cone-shaped shell called the capsid, which encases the viral ribonucleoprotein complex (vRNP). Following cellular entry, the capsid is disassembled through a poorly understood process referred to as uncoating, which is required to release the reverse transcribed HIV-1 genome for integration into host chromatin. Whereas single virus imaging using indirect CA labeling techniques suggested uncoating to occur in the cytoplasm or at the nuclear pore, a recent study using eGFP-tagged CA reported uncoating in the nucleus. To delineate the HIV-1 uncoating site, we investigated the mechanism of eGFP-tagged CA incorporation into capsids and the utility of this fluorescent marker for visualizing HIV-1 uncoating. We find that virion incorporated eGFP-tagged CA is effectively excluded from the capsid shell, and that a subset of the tagged CA is vRNP associated. These results thus imply that eGFP-tagged CA is not a direct marker for capsid uncoating. We further show that native CA co-immunoprecipitates with vRNP components, providing a basis for retention of eGFP-tagged and untagged CA by sub-viral complexes in the nucleus. Moreover, we find that functional viral replication complexes become accessible to integrase-interacting host factors at the nuclear pore, leading to inhibition of infection and demonstrating capsid permeabilization prior to nuclear import. Finally, we find that HIV-1 cores containing a mixture of wild-type and mutant CA interact differently with cytoplasmic versus nuclear pools of the CA-binding host cofactor CPSF6. Our results suggest that capsid remodeling (including a loss of capsid integrity) is the predominant pathway for HIV-1 nuclear entry and provide new insights into the mechanism of CA retention in the nucleus via interaction with vRNP components., Competing Interests: The authors have declared that no competing interests exist.

An assembly of capsid proteins (CA) form the mature viral core enclosing the HIV-1 ribonucleoprotein complex. Discrepant findings have been reported regarding the cellular sites and the extent of core disassembly (uncoating) in infected cells. Here, we combined single-virus imaging and time-of-drug-addition assays to elucidate the kinetic relationship between uncoating, reverse transcription, and nuclear import of HIV-1 complexes in cell lines and monocyte-derived macrophages (MDMs). By using cyclophilin A-DsRed (CDR) as a marker for CA, we show that, in contrast to TZM-bl cells, early cytoplasmic uncoating (loss of CDR) is limited in MDMs and is correlated with the efficiency of reverse transcription. However, we find that reverse transcription is dispensable for HIV-1 nuclear import, which progressed through an uncoating step at the nuclear pore. Comparison of the kinetics of nuclear import and the virus escape from inhibitors targeting distinct steps of infection, as well as direct quantification of viral DNA synthesis, revealed that reverse transcription is completed after nuclear import of HIV-1 complexes. Collectively, these results suggest that reverse transcription is dispensable for the uncoating step at the nuclear pore and that vDNA synthesis is completed in the nucleus of unrelated target cells.

The early steps of HIV-1 infection, such as uncoating, reverse transcription, nuclear import, and transport to integration sites are incompletely understood. Here, we imaged nuclear entry and transport of HIV-1 replication complexes in cell lines, primary monocyte-derived macrophages (MDMs) and CD4 + T cells. We show that viral replication complexes traffic to and accumulate within nuclear speckles and that these steps precede the completion of viral DNA synthesis. HIV-1 transport to nuclear speckles is dependent on the interaction of the capsid proteins with host cleavage and polyadenylation specificity factor 6 (CPSF6), which is also required to stabilize the association of the viral replication complexes with nuclear speckles. Importantly, integration site analyses reveal a strong preference for HIV-1 to integrate into speckle-associated genomic domains. Collectively, our results demonstrate that nuclear speckles provide an architectural basis for nuclear homing of HIV-1 replication complexes and subsequent integration into associated genomic loci.

Live cell fluorescence imaging is the method of choice for studying dynamic processes, such as nuclear transport, vesicular trafficking, and virus entry and egress. However, endogenous cellular autofluorescence masks a useful fluorescence signal, limiting the ability to reliably visualize low-abundance fluorescent proteins. Here, we employed synchronously amplified fluorescence image recovery (SAFIRe), which optically alters ground versus photophysical dark state populations within fluorescent proteins to modulate and selectively detect their background-free emission. Using a photoswitchable rsFastLime fluorescent protein combined with a simple illumination and image-processing scheme, we demonstrate the utility of this approach for suppressing undesirable, unmodulatable fluorescence background. Significantly, we adapted this technique to different commercial wide-field and spinning-disk confocal microscopes, obtaining >10-fold improvements in signal to background. SAFIRe allowed visualization of rsFastLime targeted to mitochondria by efficiently suppressing endogenous autofluorescence or overexpressed cytosolic unmodulatable EGFP. Suppression of the overlapping EGFP signal provided a means to perform multiplexed imaging of rsFastLime and spectrally overlapping fluorophores. Importantly, we used SAFIRe to reliably visualize and track single rsFastLime-labeled HIV-1 particles in living cells exhibiting high and uneven autofluorescence signals. Time-lapse SAFIRe imaging can be performed for an extended period of time to visualize HIV-1 entry into cells. SAFIRe should be broadly applicable for imaging live cell dynamics with commercial microscopes, even in strongly autofluorescent cells or cells expressing spectrally overlapping fluorescent proteins., (© 2019 Chen et al.)

The HIV-1 capsid executes essential functions that are regulated by capsid stability and host factors. In contrast to increasing knowledge on functional roles of capsid-interacting host proteins during postentry steps, less is known about capsid stability and its impact on intracellular events. Here, using the antiviral compound PF-3450074 (PF74) as a probe for capsid function, we uncovered a novel phenotype of capsid stability that has a profound effect on innate sensing of viral DNA by the DNA sensor cGAS. A single mutation, R143A, in the capsid protein conferred resistance to high concentrations of PF74, without affecting capsid binding to PF74. A cell-free assay showed that the R143A mutant partially counteracted the capsid-destabilizing activity of PF74, pointing to capsid stabilization as a resistance mechanism for the R143A mutant. In monocytic THP-1 cells, the R143A virus, but not the wild-type virus, suppressed cGAS-dependent innate immune activation. These results suggest that capsid stabilization improves the shielding of viral DNA from innate sensing. We found that a naturally occurring transmitted founder (T/F) variant shares the same properties as the R143A mutant with respect to PF74 resistance and DNA sensing. Imaging assays revealed delayed uncoating kinetics of this T/F variant and the R143A mutant. All these phenotypes of this T/F variant were controlled by a genetic polymorphism located at the trimeric interface between capsid hexamers, thus linking these capsid-dependent properties. Overall, this work functionally connects capsid stability to innate sensing of viral DNA and reveals naturally occurring phenotypic variation in HIV-1 capsid stability. IMPORTANCE The HIV-1 capsid, which is made from individual viral capsid proteins (CA), is a target for a number of antiviral compounds, including the small-molecule inhibitor PF74. In the present study, we utilized PF74 to identify a transmitted/founder (T/F) strain that shows increased capsid stability. Interestingly, PF74-resistant variants prevented cGAS-dependent innate immune activation under a condition where the other T/F strains induced type I interferon. These observations thus reveal a new CA-specific phenotype that couples capsid stability to viral DNA recognition by cytosolic DNA sensors., (Copyright © 2019 American Society for Microbiology.)

Allosteric HIV-1 integrase (IN) inhibitors (ALLINIs) are a promising new class of antiretroviral agents that disrupt proper viral maturation by inducing hyper-multimerization of IN. Here we show that lead pyridine-based ALLINI KF116 exhibits striking selectivity for IN tetramers versus lower order protein oligomers. IN structural features that are essential for its functional tetramerization and HIV-1 replication are also critically important for KF116 mediated higher-order IN multimerization. Live cell imaging of single viral particles revealed that KF116 treatment during virion production compromises the tight association of IN with capsid cores during subsequent infection of target cells. We have synthesized the highly active (-)-KF116 enantiomer, which displayed EC 50 of ~7 nM against wild type HIV-1 and ~10 fold higher, sub-nM activity against a clinically relevant dolutegravir resistant mutant virus suggesting potential clinical benefits for complementing dolutegravir therapy with pyridine-based ALLINIs., Competing Interests: PK, AF, ND, SR, AH, JL, DA, RL, MW, AE, DL, JF, RL, GM, MK No competing interests declared, (© 2019, Koneru et al.)

Live-cell imaging of single HIV-1 entry offers a unique opportunity to delineate the spatio-temporal regulation of infection. Novel virus labeling and imaging approaches enable the visualization of key steps of HIV-1 entry leading to nuclear import, integration into the host genome, and viral protein expression. Here, we discuss single virus imaging strategies, focusing on live-cell imaging of single virus fusion and productive uncoating that culminates in HIV-1 infection.

The HIV-1 core consists of capsid proteins (CA) surrounding viral genomic RNA. After virus-cell fusion, the core enters the cytoplasm and the capsid shell is lost through uncoating. CA loss precedes nuclear import and HIV integration into the host genome, but the timing and location of uncoating remain unclear. By visualizing single HIV-1 infection, we find that CA is required for core docking at the nuclear envelope (NE), whereas early uncoating in the cytoplasm promotes proteasomal degradation of viral complexes. Only docked cores exhibiting accelerated loss of CA at the NE enter the nucleus. Interestingly, a CA mutation (N74D) altering virus engagement of host factors involved in nuclear transport does not alter the uncoating site at the NE but reduces the nuclear penetration depth. Thus, CA protects HIV-1 complexes from degradation, mediates docking at the nuclear pore before uncoating, and determines the depth of nuclear penetration en route to integration., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Enveloped viruses transfer their genomes into host cells by fusing their membrane to that of the cell. To visualize single-virus fusion in living cells, researchers take advantage of the proteolytic maturation of HIV, type 1 (HIV-1), which can generate free fluorescent proteins within the viral particle. Co-labeling viruses with a content marker and a fluorescently tagged Vpr (a viral core protein) enables detection of single-virus fusions, but a major limitation of this approach is that not all viral particles incorporate both markers. Here we designed a labeling strategy based on the bifunctional mCherry-2xCL-YFP-Vpr construct, in which 2xCL denotes a tandem cleavage site for the viral protease. This bifunctional marker was efficiently cleaved during virus maturation, producing free mCherry and the core-associated YFP-Vpr. A nearly perfect colocalization of these two markers in virions and their fixed 1:1 ratio enabled automated detection of single-particle fusion in both fixed and live cells based on loss of the mCherry signal. Furthermore, a drop in FRET efficiency between YFP and mCherry because of cleavage of the bifunctional marker, which manifested as a marked shift in the normalized YFP/mCherry fluorescence ratio, reliably predicted viral protease activity in single virions. This feature could discriminate between the particles containing free mCherry, and therefore likely representing mature viruses, and immature particles whose fusion cannot be detected. In summary, our new labeling strategy offers several advantages compared with previous approaches, including increased reliability and throughput of detection of viral fusion. We anticipate that our method will have significant utility for studying viral fusion and maturation., (© 2017 by The American Society for Biochemistry and Molecular Biology, Inc.)

HIV-1 particles assemble and bud from the plasma membrane of infected T lymphocytes. Infected macrophages, in contrast, accumulate particles within an apparent intracellular compartment known as the virus-containing compartment or VCC. Many aspects of the formation and function of the VCC remain unclear. Here we demonstrate that VCC formation does not actually require infection of the macrophage, but can be reproduced through the exogenous addition of non-infectious virus-like particles or infectious virions to macrophage cultures. Particles were captured by Siglec-1, a prominent cell surface lectin that attaches to gangliosides on the lipid envelope of the virus. VCCs formed within infected macrophages were readily targeted by the addition of ganglioside-containing virus-like particles to the extracellular media. Depletion of Siglec-1 from the macrophage or depletion of gangliosides from viral particles prevented particle uptake into the VCC and resulted in substantial reductions of VCC volume. Furthermore, Siglec-1-mediated virion capture and subsequent VCC formation was required for efficient trans-infection of autologous T cells. Our results help to define the nature of this intracellular compartment, arguing that it is a compartment formed by particle uptake from the periphery, and that this compartment can readily transmit virus to target T lymphocytes. Inhibiting or eliminating the VCC may be an important component of strategies to reduce HIV transmission and to eradicate HIV reservoirs., Competing Interests: The authors have declared that no competing interests exist.

Disassembly of the cone-shaped HIV-1 capsid in target cells is a prerequisite for establishing a life-long infection. This step in HIV-1 entry, referred to as uncoating, is critical yet poorly understood. Here we report a novel strategy to visualize HIV-1 uncoating using a fluorescently tagged oligomeric form of a capsid-binding host protein cyclophilin A (CypA-DsRed), which is specifically packaged into virions through the high-avidity binding to capsid (CA). Single virus imaging reveals that CypA-DsRed remains associated with cores after permeabilization/removal of the viral membrane and that CypA-DsRed and CA are lost concomitantly from the cores in vitro and in living cells. The rate of loss is modulated by the core stability and is accelerated upon the initiation of reverse transcription. We show that the majority of single cores lose CypA-DsRed shortly after viral fusion, while a small fraction remains intact for several hours. Single particle tracking at late times post-infection reveals a gradual loss of CypA-DsRed which is dependent on reverse transcription. Uncoating occurs both in the cytoplasm and at the nuclear membrane. Our novel imaging assay thus enables time-resolved visualization of single HIV-1 uncoating in living cells, and reveals the previously unappreciated spatio-temporal features of this incompletely understood process.