RESUMEN
BACKGROUND: Lebanon ratified the International Health Regulations (IHR) (2005) in 2007, and since then, it has been facing complex political deadlocks, financial deterioration, and infectious disease emergencies. We aimed to understand the IHR capacities' scores of Lebanon in comparison to other countries, the IHR milestones and activities in Lebanon, the challenges of maintaining the IHR capacities, the refugee crisis's impact on the development of these capacities; and the possible recommendations to support the IHR performance in Lebanon. METHODS: We used a mixed-method design. The study combined the use of secondary data analysis of the 2020 State Party Self-Assessment Annual Report (SPAR) submissions and qualitative design using semi-structured interviews with key informants. Semi-structured interviews were conducted with nine key informants. The analysis of the data generated was based on inductive thematic analysis. RESULTS: According to SPAR, Lebanon had levels of 4 out of 5 (≤ 80%) in 2020 in the prevention, detection, response, enabling functions, and operational readiness capacities, pertaining that the country was functionally capable of dealing with various events at the national and subnational levels. Lebanon scored more than its neighboring countries, Syria, and Jordan, which have similar contexts of economic crises, emergencies, and refugee waves. Despite this high level of commitment to meeting IHR capacities, the qualitative findings demonstrated several gaps in IHR performance as resource shortage, governance, and political challenges. The study also showed contradictory results regarding the impact of refugees on IHR capacities. Some key informants agreed that the Syrian crisis had a positive impact, while others suggested the opposite. Whether refugees interfere with IHR development is still an area that needs further investigation. CONCLUSION: The study shows that urgent interventions are needed to strengthen the implementation of the IHR capacities in Lebanon. The study recommends 1) reconsidering the weight given to IHR capacities; 2) promoting governance to strengthen IHR compliance; 3) strengthening the multisectoral coordination mechanisms; 4) reinforcing risk communication strategies constantly; 5) mobilizing and advancing human resources at the central and sub-national levels; 6) ensuring sustainable financing; 7) integrating refugees and displaced persons in IHR framework and its assessment tools; 8) acknowledging risk mapping as a pre-requisite to a successful response; and 9) strengthening research on IHR capacities in Lebanon.
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Enfermedades Transmisibles , Refugiados , Humanos , Reglamento Sanitario Internacional , Líbano , Urgencias Médicas , SiriaRESUMEN
Developing modulatory antibodies against G protein-coupled receptors is challenging. In this study, we targeted the follicle-stimulating hormone receptor (FSHR), a significant regulator of reproduction, with variable domains of heavy chain-only antibodies (VHHs). We built two immune VHH libraries and submitted them to multiplexed phage display approaches. We used next-generation sequencing to identify 34 clusters of specifically enriched sequences that were functionally assessed in a primary screen based on a cAMP response element (CRE)-dependent reporter gene assay. In this assay, 23 VHHs displayed negative or positive modulation of FSH-induced responses, suggesting a high success rate of the multiplexed strategy. We then focused on the largest cluster identified (i.e., PRC1) that displayed positive modulation of FSH action. We demonstrated that PRC1 specifically binds to the human FSHR and human FSHR/FSH complex while potentiating FSH-induced cAMP production and Gs recruitment. We conclude that the improved selection strategy reported here is effective for rapidly identifying functionally active VHHs and could be adapted to target other challenging membrane receptors. This study also led to the identification of PRC1, the first potential positive modulator VHH reported for the human FSHR.
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Bacteriófagos , Receptores de HFE , Humanos , Receptores de HFE/genética , Receptores de HFE/metabolismo , Hormona Folículo Estimulante/metabolismo , Transducción de Señal , Secuenciación de Nucleótidos de Alto Rendimiento , Bacteriófagos/genéticaRESUMEN
Inhibition of α-amylase enzyme is of key significance for the therapy of diabetes mellitus (DM). Numerous indole-based compounds have earlier been described for broad range of bioactivities. From our previous study, we knew that indole and thiadiazole are potent inhibitors of diabetics II. We design the hybrid molecules of them and synthesized 18 derivatives of indole-based-thiadiazole (1-18). All synthesized compounds were characterized using different spectroscopic methods and evaluated for their α-amylase inhibitory activities. All synthetic compounds, except 4, 13, 15 and 16, were found to be strongly active (IC50 values in the range of 0.80 ± 0.05 - 9.30 ± 0.20 µM) than the standard drug, acarbose (IC50 = 11.70 ± 0.10 µM). Nevertheless, compound 18 was found to be inactive. The modes of binding interactions of five most active compounds 2, 3, 5, 10 and 17 were also studies through molecular docking study. In brief, current study identifies a novel class of α-amylase inhibitors which can be further studied for the treatment of hyperglycemia and obesity.Communicated by Ramaswamy H. Sarma.
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Diabetes Mellitus , Tiadiazoles , Humanos , Estructura Molecular , Relación Estructura-Actividad , Hipoglucemiantes/farmacología , Tiadiazoles/farmacología , Tiadiazoles/química , Simulación del Acoplamiento Molecular , Indoles/farmacología , Indoles/química , alfa-AmilasasRESUMEN
Quaternary structure of human, bovine and ovine Follicle-Stimulating Hormones (hFSH, bFSH and oFSH) and Luteinizing Hormone was assessed in sandwich ELISAs using monoclonal anti-oFSHß or anti-oLHß antibodies, respectively, for capture and a biotinylated anti-hFSHα (α4 epitope) for detection. Neither free subunit gave any signal in this assay so that it was possible to measure the residual heterodimeric fraction after thermal treatment of the gonadotropins under study. The hormones were subjected to 5-min heating between 37 and 90 °C before rapid cooling in melting ice before ELISA. The data show half-dissociation of natural and recombinant human and ovine FSH preparations between 68 and 74 °C whereas bovine FSH preparations exhibited lower stability in these conditions with half-dissociation between 61 and 64 °C. Moreover, whereas all human and bovine as well as most ovine FSH preparations were fully dissociated at temperatures above 80 °C, one natural oFSH and one recombinant hLH preparations contained an important fraction that resisted dissociation even at 93 °C and retained in vitro bioactivity. This suggests the existence of gonadotropin αß heterodimer with covalently linked subunits. Similarly, about 20% of the recombinant hLH preparation was also found withstand heat denaturation and also probably to have cross-linked subunits. The origin and chemical nature of these inter-subunit bonds remain to be determined.
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Hormona Folículo Estimulante/química , Hormona Folículo Estimulante/metabolismo , Hormona Luteinizante/química , Hormona Luteinizante/metabolismo , Animales , Anticuerpos Monoclonales/inmunología , Bioensayo , Bovinos , Células Cultivadas , Ensayo de Inmunoadsorción Enzimática , Células HEK293 , Calor , Humanos , Células Intersticiales del Testículo , Masculino , Ratones , OvinosRESUMEN
Isolation of phosphatidyl-ethanolamine-binding protein-1 (PEBP-1) from bovine brain was described almost three decades ago but it required a large number of steps to reach high purity. After the fractionation of bovine testis proteins by ammonium sulfate precipitation we found that PEBP-1, detected by Western blotting, was among the very few proteins still soluble at 80% ammonium sulfate saturation (3.2M). This soluble fraction (S80) was directly loaded onto a phenyl sepharose column equilibrated at the same ammonium sulfate concentration (3.2M). A stepwise elution of the retained material at 1.0, 0.5, 0.2, 0.1M ammonium sulfate in ammonium hydrogen carbonate was performed and then with ammonium hydrogen carbonate alone and finally with 50% ethylene glycol. All fractions were analyzed by SDS-PAGE and Western blotting and the fractions containing PEBP-1 was further fractionated by size exclusion chromatography on a HR75 Superdex column permitting the isolation of ubiquitin in addition to PEBP-1 as demonstrated by Western blotting and mass spectrometry. This study shows the feasibility of hydrophobic interaction chromatography (HIC) on phenyl sepharose at a very high ammonium sulfate concentration (3.2M; 80% saturation) to efficiently purify the proteins that are still soluble in these extreme conditions.
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Cromatografía Liquida/métodos , Proteínas de Unión a Fosfatidiletanolamina/aislamiento & purificación , Testículo/química , Ubiquitina/aislamiento & purificación , Sulfato de Amonio/química , Animales , Western Blotting , Bovinos , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Interacciones Hidrofóbicas e Hidrofílicas , Masculino , Proteínas de Unión a Fosfatidiletanolamina/química , Ubiquitina/químicaRESUMEN
Protein disulphide isomerase (PDI) in the endoplasmic reticulum catalyzes the rearrangement of disulphide bridges during folding of secreted proteins. It binds various molecules that inhibit its activity. But here, we looked for molecules that would potentiate its activity. PDI reductase activity was measured in vitro using di-eosin-oxidized glutathione as substrate. Its classical inhibitor bacitracin was found to exert a biphasic effect: stimulatory at low concentrations (â¼10(-6) M) and inhibitory only at higher concentrations (â¼10(-4)-10(-3) M). The weak oestrogenic molecule bisphenol A was found to exert a weak inhibitory effect on PDI reductase activity relative to the strong oestrogens, ethynylestradiol, and diethylstilbestrol. Like 19-nortestosterone, fluoxetine was found to exert a potentiating effect on PDI reductase activity and their potentiating effects could be reversed by increasing concentrations of oestrogens. In conclusion, this paper provides the first identification of potentiators of PDI activity that are potential pharmaceuticals against pathologies affecting protein folding such as Alzheimer's disease.