Chemical and biological investigations of Delonix regia (Bojer ex Hook.) Raf.

U radu je opisana izolacija pet sastojaka petroleterske i diklormetanske frakcije metanolnog ekstrakta kore biljke Delonix regia: lupeol (1), epilupeol (2), β-sitosterol (3), stigmasterol (4) i p-metoksibenzaldehid (5). Nadalje, testirano je antimikrobno djelovanje različitih ekstrakata difuzijskom metodom na disku (15 μg mm2). Zone inhibicije za sastojke topljive u petroleteru, tetraklormetanu i diklormetanu bile su 914 mm, 1113 mm, odnosno 920 mm, dok je zona inhibicije standarda kanamicina bila 2025 mm. U biološkom pokusu smrtnosti morskih kozica najveću toksičnost pokazali su spojevi topljivi u tetraklormetanu (LC50 = 0,83 μg mL1), dok je topljivost sastojaka topljivih u petroleteru i diklormetanu bila LC50 14,94, odnosno 3,29 μg mL1, a standarda vinkristin sulfata 0,812 μg mL1. Ovo je prvo izvješće o izolaciji sastojaka, antimikrobnom djelovanju i citotoksičnosti biljke D. regia.In this study five compounds, lupeol (1), epilupeol (2), β-sitosterol (3), stigmasterol (4) and p-methoxybenzaldehyde (5) were isolated from the petroleum ether and dichloromethane fractions of a methanolic extract of the stem bark of Delonix regia. Antimicrobial screening of the different extracts (15 μg mm2) was conducted by disc diffusion method. The zones of inhibition demonstrated by the petroleum ether, carbon tetrachloride and dichloromethane fractions ranged from 914 mm, 1113 mm and 920 mm, respectively, compared to kanamycin standard with the zone of inhibition of 2025 mm. In brine shrimp lethality bioassay, the carbon tetrachloride soluble materials demonstrated the highest toxicity with LC50 of 0.83 μg mL1, while petroleum ether and dichloromethane soluble partitionates of the methanolic extract revealed LC50 of 14.94 and 3.29 μg mL1, respectively, in comparison with standard vincristine sulphate with LC50 of 0.812 μg mL1. This is the first report on compounds separation from D. regia, their antimicrobial activity and cytotoxicity

In vitro Antioxidant and Membrane Stabilizing Activities of Oxalis corniculata Linn.

The methanolic extract of the whole plant of Oxalis corniculata was evaluated for antioxidant and membrane stabilizing activities. The total phenolics in the methanol extract was found 213.69 mg of gallic acid per g of extract when determined using the Folin-Ciocalteu reagent. Besides, antioxidant activity was also assessed by various methods, including free radical, hydrogen peroxide, and nitric oxide scavenging and phosphomolybdenum antioxidant assay and reducing power determination. In these cases, butylated hydroxytoluene (BHT) and ascorbic acid were used as a standard antioxidants. The membrane stabilizing activity was assessed by using erythrocyte in hypotonic solution, using indomethacin as the standard. It was revealed that the methanolic extract of O. corniculata demonstrated moderate antioxidant activity and significant membrane stabilizing property.Colegio de Farmacéuticos de la Provincia de Buenos Aire

In vitro antioxidant, reducing power, free radical scavenging and membrane stabilizing activities of seeds of Syzygium cumini L.

Different extractives of Syzygium cumini seeds were evaluated by free radical (DPPH) scavenging assay, phosphomolybdenum total antioxidant assay and reducing power determination in order to identify promising sources of antioxidants along with its membrane stabilizing activity. The total phenolic content was also determined and expressed in gallic acid equivalent. Here, butylated hydroxytoluene (BHT) and ascorbic acid (ASA) were used as standard antioxidants. The membrane stabilizing activity was assessed by using erythrocytes in hypotonic solution and was compared with acetyl salicylic acid. A positive correlation was observed between total phenolic content and total antioxidant activity as well as reducing power of S. cumini having correlation coefficient (R2 ) values of 0.8177 and 0.9818, respectively. In the present studies, the methanol extract and its aqueous and petroleum ether soluble partitionates demonstrated significant antioxidant potentials.Colegio de Farmacéuticos de la Provincia de Buenos Aire

Investigaciones fitoquímicas y biológicas de extractos metanólicos de hojas de Ziziphus mauritiana Lam

Siete compuestos fueron aislados del extracto metanólico de hojas de Ziziphus mauritiana. Las estructuras de los compuestos aislados fueron identificadas como γ-fagarina (1), β-sitosterol (2), estigmasterol (3), α-amirina (4), lupeol (5), β-amirina (6) y betulina (7 ) por medio de extensivos estudios espectroscópicos y por co-TLC con muestras auténticas. Este es el primer informe de aislamiento de los compuestos 1-7 a partir de esta especie vegetal. Los extractos de las hojas fueron investigados por efectos trombolíticos, estabilizadores de membrana, antimicrobianos, antidiarreicos y potenciales analgésicos junto a la propiedad de inducir sueño en el modelo animal. Las actividades trombolíticos y la estabilización de la membrana se evaluaron mediante el uso de eritrocitos humanos comparando con estreptoquinasa estándar y el ácido acetilsalicílico, respectivamente. El extracto metanólico redujo la frecuencia de las heces diarreicas en comparación con el estándar de loperamida. En la inducción por aceite de ricino de diarrea en ratones, se observó una disminución dosis dependiente de los tránsitos gastrointestinales. En el método del coletazo producido por calor radiante, el extracto metabólico mostró una actividad antinociceptiva moderada, en comparación con la morfina estándar

Clausenolide-1-methyl ether from Clausena heptaphylla W&A [Clausenolido-1-metil éter de Clausena heptaphylla W & A]

El limonoíde clausenolido-1-metil eter (1) fue aislado de corteza de Clausena heptaphylla. La estructura del compuesto fue determinada por metodos espectroscópicos, incluyendo 2D RMN, espectrometría de masas (EM) y comparación de los datos espectroscópicos y constantes físicas con los publicados en la literatura. Este es el primer informe del aislamiento de clausenolido-1-metil eter (1) de Clausena heptaphylla.Abstract From the stem bark of Clausena heptaphylla, the limonoid  clausenolide-1-methyl ether (1) was isolated. The structure of the compound was elucidated by extensive spectroscopic studies, including 2D NMR and MS measurements and by comparison with spectroscopic and physical data from the literature. This is the first report of occurrence of clausenolide-1-methyl ether (1) in Clausena heptaphyll

A Multicentre Study of Shigella Diarrhoea in Six Asian Countries: Disease Burden, Clinical Manifestations, and Microbiology

BACKGROUND: The burden of shigellosis is greatest in resource-poor countries. Although this diarrheal disease has been thought to cause considerable morbidity and mortality in excess of 1,000,000 deaths globally per year, little recent data are available to guide intervention strategies in Asia. We conducted a prospective, population-based study in six Asian countries to gain a better understanding of the current disease burden, clinical manifestations, and microbiology of shigellosis in Asia. METHODS AND FINDINGS: Over 600,000 persons of all ages residing in Bangladesh, China, Pakistan, Indonesia, Vietnam, and Thailand were included in the surveillance. Shigella was isolated from 2,927 (5%) of 56,958 diarrhoea episodes detected between 2000 and 2004. The overall incidence of treated shigellosis was 2.1 episodes per 1,000 residents per year in all ages and 13.2/1,000/y in children under 60 months old. Shigellosis incidence increased after age 40 years. S. flexneri was the most frequently isolated Shigella species (1,976/2,927 [68%]) in all sites except in Thailand, where S. sonnei was most frequently detected (124/146 [85%]). S. flexneri serotypes were highly heterogeneous in their distribution from site to site, and even from year to year. PCR detected ipaH, the gene encoding invasion plasmid antigen H in 33% of a sample of culture-negative stool specimens. The majority of S. flexneri isolates in each site were resistant to amoxicillin and cotrimoxazole. Ciprofloxacin-resistant S. flexneri isolates were identified in China (18/305 [6%]), Pakistan (8/242 [3%]), and Vietnam (5/282 [2%]). CONCLUSIONS: Shigella appears to be more ubiquitous in Asian impoverished populations than previously thought, and antibiotic-resistant strains of different species and serotypes have emerged. Focusing on prevention of shigellosis could exert an immediate benefit first by substantially reducing the overall diarrhoea burden in the region and second by preventing the spread of panresistant Shigella strains. The heterogeneous distribution of Shigella species and serotypes suggest that multivalent or cross-protective Shigella vaccines will be needed to prevent shigellosis in Asia

Future-ai:International consensus guideline for trustworthy and deployable artificial intelligence in healthcare

Despite major advances in artificial intelligence (AI) for medicine and healthcare, the deployment and adoption of AI technologies remain limited in real-world clinical practice. In recent years, concerns have been raised about the technical, clinical, ethical and legal risks associated with medical AI. To increase real world adoption, it is essential that medical AI tools are trusted and accepted by patients, clinicians, health organisations and authorities. This work describes the FUTURE-AI guideline as the first international consensus framework for guiding the development and deployment of trustworthy AI tools in healthcare. The FUTURE-AI consortium was founded in 2021 and currently comprises 118 inter-disciplinary experts from 51 countries representing all continents, including AI scientists, clinicians, ethicists, and social scientists. Over a two-year period, the consortium defined guiding principles and best practices for trustworthy AI through an iterative process comprising an in-depth literature review, a modified Delphi survey, and online consensus meetings. The FUTURE-AI framework was established based on 6 guiding principles for trustworthy AI in healthcare, i.e. Fairness, Universality, Traceability, Usability, Robustness and Explainability. Through consensus, a set of 28 best practices were defined, addressing technical, clinical, legal and socio-ethical dimensions. The recommendations cover the entire lifecycle of medical AI, from design, development and validation to regulation, deployment, and monitoring. FUTURE-AI is a risk-informed, assumption-free guideline which provides a structured approach for constructing medical AI tools that will be trusted, deployed and adopted in real-world practice. Researchers are encouraged to take the recommendations into account in proof-of-concept stages to facilitate future translation towards clinical practice of medical AI

FUTURE-AI: International consensus guideline for trustworthy and deployable artificial intelligence in healthcare

Despite major advances in artificial intelligence (AI) for medicine and healthcare, the deployment and adoption of AI technologies remain limited in real-world clinical practice. In recent years, concerns have been raised about the technical, clinical, ethical and legal risks associated with medical AI. To increase real world adoption, it is essential that medical AI tools are trusted and accepted by patients, clinicians, health organisations and authorities. This work describes the FUTURE-AI guideline as the first international consensus framework for guiding the development and deployment of trustworthy AI tools in healthcare. The FUTURE-AI consortium was founded in 2021 and currently comprises 118 inter-disciplinary experts from 51 countries representing all continents, including AI scientists, clinicians, ethicists, and social scientists. Over a two-year period, the consortium defined guiding principles and best practices for trustworthy AI through an iterative process comprising an in-depth literature review, a modified Delphi survey, and online consensus meetings. The FUTURE-AI framework was established based on 6 guiding principles for trustworthy AI in healthcare, i.e. Fairness, Universality, Traceability, Usability, Robustness and Explainability. Through consensus, a set of 28 best practices were defined, addressing technical, clinical, legal and socio-ethical dimensions. The recommendations cover the entire lifecycle of medical AI, from design, development and validation to regulation, deployment, and monitoring. FUTURE-AI is a risk-informed, assumption-free guideline which provides a structured approach for constructing medical AI tools that will be trusted, deployed and adopted in real-world practice. Researchers are encouraged to take the recommendations into account in proof-of-concept stages to facilitate future translation towards clinical practice of medical AI

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

A Review on Phytochemicals from Some Medicinal Plants of Bangladesh

Natural products, especially those derived from higher plants, have attracted scientists from ancient time because of their potential therapeutic values. Drug development from natural sources showed that natural products or natural product-derived drugs comprised about 28% of all new chemical entities launched to the market. These are originated from terrestrial plants, microbes, marine organisms, etc. However, until recently an insignificant part of the plants has been scientifically evaluated for their medicinal properties. Bangladesh is a rich repository of medicinal plants, many of which are widely used in the Ayurvedic, Unani, herbal and other traditional systems of medicines. In our laboratory, we have extensively investigated over 48 medicinal plants and several microbial strains that have resulted in the isolation and characterization of 133 compounds, including 33 new molecules. Terpenoids, alkaloids, flavonoids and glycosides were the major classes of constituents. The crude extractives and several purified molecules demonstrated statistically significant inhibition of growth of microorganisms. On the other hand, usnic acid obtained from the lichen, Parmelia kamtschandalis, demonstrated even better of inhibition of microbial growth as compared to the standard antimicrobial agents, whereas dehydroaltenusin extracted from a Streptomyces sp. exhibited significant HIV-inhibitory activity