111 research outputs found

    An overview of anti-diabetic plants used in Gabon: Pharmacology and Toxicology

    Get PDF
    © 2017 Elsevier B.V. All rights reserved.Ethnopharmacological relevance: The management of diabetes mellitus management in African communities, especially in Gabon, is not well established as more than 60% of population rely on traditional treatments as primary healthcare. The aim of this review was to collect and present the scientific evidence for the use of medicinal plants that are in currect by Gabonese traditional healers to manage diabetes or hyperglycaemia based here on the pharmacological and toxicological profiles of plants with anti-diabetic activity. There are presented in order to promote their therapeutic value, ensure a safer use by population and provide some bases for further study on high potential plants reviewed. Materials and methods: Ethnobotanical studies were sourced using databases such as Online Wiley library, Pubmed, Google Scholar, PROTA, books and unpublished data including Ph.D. and Master thesis, African and Asian journals. Keywords including ‘Diabetes’ ‘Gabon’ ‘Toxicity’ ‘Constituents’ ‘hyperglycaemia’ were used. Results: A total of 69 plants currently used in Gabon with potential anti-diabetic activity have been identified in the literature, all of which have been used in in vivo or in vitro studies. Most of the plants have been studied in human or animal models for their ability to reduce blood glucose, stimulate insulin secretion or inhibit carbohydrates enzymes. Active substances have been identified in 12 out of 69 plants outlined in this review, these include Allium cepa and Tabernanthe iboga. Only eight plants have their active substances tested for anti-diabetic activity and are suitables for further investigation. Toxicological data is scarce and is dose-related to the functional parameters of major organs such as kidney and liver. Conclusion: An in-depth understanding on the pharmacology and toxicology of Gabonese anti-diabetic plants is lacking yet there is a great scope for new treatments. With further research, the use of Gabonese anti-diabetic plants is important to ensure the safety of the diabetic patients in Gabon.Peer reviewedFinal Accepted Versio

    Contextualising social capital in online brand communities

    Get PDF
    Online brand communities (OBC) are growing in number and becoming an increasingly important interface where marketers can effectively facilitate the relationship between their brand and consumers. A qualitative study using a four-month netnography over three OBCs followed by focus groups with OBC members explored the dynamics of social capital in these communities. Findings indicate that social capital is an important driver in the success of OBCs, and all the elements of social capital including a shared language, shared vision, social trust and reciprocity are evident. Moreover, results from this study indicate that these elements are crucial in developing the network ties that are integral to building loyalty and brand equity

    Twelve-month observational study of children with cancer in 41 countries during the COVID-19 pandemic

    Get PDF
    Introduction Childhood cancer is a leading cause of death. It is unclear whether the COVID-19 pandemic has impacted childhood cancer mortality. In this study, we aimed to establish all-cause mortality rates for childhood cancers during the COVID-19 pandemic and determine the factors associated with mortality. Methods Prospective cohort study in 109 institutions in 41 countries. Inclusion criteria: children <18 years who were newly diagnosed with or undergoing active treatment for acute lymphoblastic leukaemia, non-Hodgkin's lymphoma, Hodgkin lymphoma, retinoblastoma, Wilms tumour, glioma, osteosarcoma, Ewing sarcoma, rhabdomyosarcoma, medulloblastoma and neuroblastoma. Of 2327 cases, 2118 patients were included in the study. The primary outcome measure was all-cause mortality at 30 days, 90 days and 12 months. Results All-cause mortality was 3.4% (n=71/2084) at 30-day follow-up, 5.7% (n=113/1969) at 90-day follow-up and 13.0% (n=206/1581) at 12-month follow-up. The median time from diagnosis to multidisciplinary team (MDT) plan was longest in low-income countries (7 days, IQR 3-11). Multivariable analysis revealed several factors associated with 12-month mortality, including low-income (OR 6.99 (95% CI 2.49 to 19.68); p<0.001), lower middle income (OR 3.32 (95% CI 1.96 to 5.61); p<0.001) and upper middle income (OR 3.49 (95% CI 2.02 to 6.03); p<0.001) country status and chemotherapy (OR 0.55 (95% CI 0.36 to 0.86); p=0.008) and immunotherapy (OR 0.27 (95% CI 0.08 to 0.91); p=0.035) within 30 days from MDT plan. Multivariable analysis revealed laboratory-confirmed SARS-CoV-2 infection (OR 5.33 (95% CI 1.19 to 23.84); p=0.029) was associated with 30-day mortality. Conclusions Children with cancer are more likely to die within 30 days if infected with SARS-CoV-2. However, timely treatment reduced odds of death. This report provides crucial information to balance the benefits of providing anticancer therapy against the risks of SARS-CoV-2 infection in children with cancer

    Identifying reputation collectors in community question answering (CQA) sites: Exploring the dark side of social media

    Get PDF
    YesThis research aims to identify users who are posting as well as encouraging others to post low-quality and duplicate contents on community question answering sites. The good guys called Caretakers and the bad guys called Reputation Collectors are characterised by their behaviour, answering pattern and reputation points. The proposed system is developed and analysed over publicly available Stack Exchange data dump. A graph based methodology is employed to derive the characteristic of Reputation Collectors and Caretakers. Results reveal that Reputation Collectors are primary sources of low-quality answers as well as answers to duplicate questions posted on the site. The Caretakers answer limited questions of challenging nature and fetches maximum reputation against those questions whereas Reputation Collectors answers have so many low-quality and duplicate questions to gain the reputation point. We have developed algorithms to identify the Caretakers and Reputation Collectors of the site. Our analysis finds that 1.05% of Reputation Collectors post 18.88% of low quality answers. This study extends previous research by identifying the Reputation Collectors and 2 how they collect their reputation points

    Large expert-curated database for benchmarking document similarity detection in biomedical literature search

    Get PDF
    Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

    Isolation of an N-acetyl-d-glucosamine specific lectin from the rhizomes of Arundo donax with antiproliferative activity

    No full text
    A lectin with antiproliferative activity towards human cancer cell lines and mitogenic towards human peripheral blood mononuclear cells was purified from the rhizomes of Arundo donax (Linn.) by affinity chromatography on N-acetyl-D-glucosamine linked to epoxy-activated sepharose-6B. The pure preparation apparently yielded a single band of approximately 15 kDa on SDS–PAGE,pH 8.3, under both reducing and non-reducing conditions. The molecular mass of native lectin was 32 kDa as determined by gel filtration chromatography. This showed the lectin to be a dimer, with subunits not held together by disulphide linkages. The A. donax lectin (ADL) agglutinated rabbit erythrocytes and the agglutination was inhibited by N-acetyl-D-glucosamine and its diand trimer. The lectin was thermostable upto 55 �C and showed optimum activity in the range of pH 7.0–9.0 and comprised of 2.1% carbohydrate content

    A tuber lectin from Arisaema helleborifolium Schott with anti-insect activity against melon fruit fly, Bactrocera cucurbitae (Coquillett) and anti-cancer effect on human cancer cell lines

    No full text
    An anti-insect and anti-cancer lectin has been isolated from Arisaema helleborifolium Schott by aYnity chromatography using asialofetuin-linked amino activated silica beads. The bound A. helleborifolium lectin (AHL) was eluted with 100mM glycine–HCl buVer, pH 2.5. It gave a single band on SDS–PAGE, pH 8.3, and PAGE, pH 4.5. However, multiple bands were obtained in PAGE at pH 8.3 and isoelectric focusing. The lectin was a homotetramer having subunit molecular mass 13.4 kDa while its native molecular mass was 52 kDa. It was a glycoprotein with 3.40% carbohydrate and was stable up to 60 °C for 30 min. It showed anti-insect activity towards second instar larvae of Bactrocera cucurbitae (Coquillett) with LC50 value of 16.4 �g/ml. Larvae fed on artiWcial diet containing sub-lethal dose of AHL showed a signiWcant decrease in acid phosphatase and alkaline phosphatase activity while esterase activity markedly increased as compared to larvae fed on diet without lectin. AHL was also found to inhibit in vitro proliferation of some well established human cancer cell lines viz HOP-62 (95%), HCT-15 (92%), HEP-2 (66%), HT-29 (68%), PC-3 (39.4%), and A-549 (20.7%)

    Synthesis and antimicrobial evaluation of novel 1,3,4-thiadiazole derivatives of 2-(4-formyl-2-methoxyphenoxy) acetic acid

    Get PDF
    A series of 1,3,4-thiadiazole derivatives of 2-(4-formyl-2-methoxyphenoxy) acetic acid (6a–s) were synthesized by cyclization of carboxylic acid group of 2-(2-methoxy-4-(3-oxo-3-substituted phenylprop-1-enyl)phenoxy) acetic acid (4a–s) with thiosemicarbazide in the presence of POCl3 or PPA. The structures of the compounds were confirmed by IR, 1H NMR and mass analysis. All the compounds have been evaluated in vitro for their antimicrobial activities against several strains of microbes and show significant activity

    Generation mean analysis in maize (Zea mays) for yields and yield attributing traits.

    No full text
    Not AvailableThe nature of gene action involved is mainly responsible for the genetic improvement of any crop. Generation means analysis for maize (Zea mays L.) yield and its traits for six generations, i.e. P1, P2 F1, F2, BC1 and BC2 of six crosses evaluated at Karnal. Significant individual and joint scaling tests indicated inadequacy of three parameter models and presence of epistasis in all characters indicating greater genetic variation in parents. However, only shelling percentage in HKI 209 × HKI 163 showed additive-dominance. The presence of duplicate form of non-allelic gene interactions was prominent, except for days to maturity and cob diameter in HKI 325-17AN × HKI 163, cob length in HKI 209 × HKI 163 and shelling percentage in HKI 1332 × HKI 163 where complementary gene action is recorded. It suggests selection from F3 generation onwards for character improvement. Dominance and duplicate type of epistatic effects were found to be more prominent for inheritance than additive effects alone for grain yield/plant, grains/cob, and plant height suggesting the reciprocal recurrent selection or bi-parental mating design to improve in these characters. In crosses where dominance was of major importance, the trait could be successfully utilized for the exploitation of hybrid vigour. Some significant additive and additive × additive effects were recorded in all of these crosses, and therefore gain from selection could be possible, fixable and heritable epistasis coulNot Availabl
    corecore