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Microalgae are unicellular organisms and commonly present in the euphotic zone of marine ecosystems. From the western coast of Mauritius, three strains of Prorocentrum species were isolated from macrophytes and cultured under standard laboratory conditions. Morphologies were examined by light, fluorescence, and scanning electron microscopy, and phylogenetic analyses were based on partial large subunit LSU rDNA (D1-D2) and ITS1-5.8S-ITS2 (ITS) regions. Three Prorocentrum species, including the P. fukuyoi complex, P. rhathymum, and P. lima complex, were identified. The antimicrobial activities were assayed against potential human pathogenic bacterial strains. The highest zone of inhibition was recorded for intracellular and extracellular protein extracts of Prorocentrum rhathymum against Vibrio parahaemolyticus. The polysaccharide extracts of the Prorocentrum fukuyoi complex had a higher zone of inhibition (24 ± 0.4 mm) against MRSA at a minimum concentration of 0.625 µg/mL. The extracts from the three Prorocentrum species had different levels of activity against the pathogens used, and this can be of scientific interest in the search for antibiotics from natural marine sources.
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Anti-Infecciosos , Dinoflagellida , Humanos , DNA Ribossômico/genética , Filogenia , Ecossistema , Sequência de Bases , Oceano Índico , Maurício , Anti-Infecciosos/farmacologiaRESUMO
As the largest habitat on Earth, the marine environment harbors various microorganisms of biotechnological potential. Indeed, microbial compounds, especially polysaccharides from marine species, have been attracting much attention for their applications within the medical, pharmaceutical, food, and other industries, with such interest largely stemming from the extensive structural and functional diversity displayed by these natural polymers. At the same time, the extreme conditions within the aquatic ecosystem (e.g., temperature, pH, salinity) may not only induce microorganisms to develop a unique metabolism but may also increase the likelihood of isolating novel polysaccharides with previously unreported characteristics. However, despite their potential, only a few microbial polysaccharides have actually reached the market, with even fewer being of marine origin. Through a synthesis of relevant literature, this review seeks to provide an overview of marine microbial polysaccharides, including their unique characteristics. In particular, their suitability for specific biotechnological applications and recent progress made will be highlighted before discussing the challenges that currently limit their study as well as their potential for wider applications. It is expected that this review will help to guide future research in the field of microbial polysaccharides, especially those of marine origin.
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Bactérias , Ecossistema , Bactérias/metabolismo , Polissacarídeos/metabolismo , Biotecnologia , Organismos Aquáticos/químicaRESUMO
Decoctions (leaves and roots) of Bruguiera gymnorhiza (L.) Lam. are traditionally used against diabetes in many countries, including Mauritius. This study endeavoured to evaluate the inhibitory potential of leaves, roots, twigs and fruits extracts (decoction and maceration) of B. gymnorhiza against key enzymes relevant to diabetes. Considering complications related to diabetes, other clinical enzymes, namely, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, elastase and pancreatic lipase, were used. Identification of compounds was carried out using ultra-high-performance liquid chromatography/electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS). Antioxidant capacities were assessed using DPPH, ABTS, FRAP, CUPRAC, phosphomolybdenum, metal chelating. The relationship between mode of extraction, plant parts and biological activities was determined using multivariate analysis. Macerated fruits, rich in phytochemicals (phenolic, flavanol, tannin, and triterpenoid), exhibited substantially high antioxidant capacities related to radical scavenging (DPPH: 547.75 ± 10.99 and ABTS: 439.59 ± 19.13 mg TE/g, respectively) and reducing potential (CUPRAC: 956.04 ± 11.90 and FRAP: 577.26 ± 4.55 mg TE/g, respectively). Additionally, the same extract significantly depressed AChE and BChE (3.75 ± 0.03 and 2.19 ± 0.13 mg GALAE/g, respectively), tyrosinase (147.01 ± 0.78 mg KAE/g), elastase (3.14 ± 0.08 mg OE/g) and amylase (1.22 ± 0.01 mmol ACAE/g) enzymatic activities. Phytochemical results confirmed the presence of 119 compounds in all maceration and 163 compounds in all decoction samples. The screening also revealed important compounds in the extracts, namely, quinic acid, brugierol, bruguierol A, epigallocatechin, chlorogenic acid, to name a few. Multivariate analysis reported that the plant parts of B. gymnorhiza greatly influenced the observed biological activities in contrast to the types of extraction methods employed. Docking calculations have supported the findings of the experimental part through the high binding affinity and strong interactions of some compounds against tyrosinase, AChE, BChE and elastase enzymes. The decocted root and leaf of B. gymnorhiza showed low to moderate antidiabetic activity, thereby partially supporting its traditional uses in the management of diabetes. However, the fruit, the most active organ, can be used as a diet supplement to reduce the risk of diabetes complications after evaluating its cytotoxic effects.
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Rhizophoraceae , Plantas Tolerantes a Sal , Acetilcolinesterase/metabolismo , Butirilcolinesterase/química , Inibidores Enzimáticos/farmacologia , Flavonoides/química , Compostos Fitoquímicos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Espectrometria de Massas em TandemRESUMO
According to the World Health Organization, neurological and neurodegenerative diseases are highly debilitating and pose the greatest threats to public health. Diseases of the nervous system are caused by a particular pathological process that negatively affects the central and peripheral nervous systems. These diseases also lead to the loss of neuronal cell function, which causes alterations in the nervous system structure, resulting in the degeneration or death of nerve cells throughout the body. This causes problems with movement (ataxia) and mental dysfunction (dementia), both of which are commonly observed symptoms in Alzheimer's disease, Parkinson's disease, Huntington's disease, and multiple sclerosis. Medicinal mushrooms are higher fungi with nutraceutical properties and are low in calories and fat. They are also a rich source of nutrients and bioactive compounds such as carbohydrates, proteins, fibers, and vitamins that have been used in the treatment of many ailments. Medicinal mushrooms such as Pleurotus giganteus, Ganoderma lucidium, and Hericium erinaceus are commonly produced worldwide for use as health supplements and medicine. Medicinal mushrooms and their extracts have a large number of bioactive compounds, such as polysaccharide ß-glucan, or polysaccharide-protein complexes, like lectins, lactones, terpenoids, alkaloids, antibiotics, and metal-chelating agents. This review will focus on the role of the medicinal properties of different medicinal mushrooms that contain bioactive compounds with a protective effect against neuronal dysfunction. This information will facilitate the development of drugs against neurodegenerative diseases.
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Agaricales , Ganoderma , Doenças Neurodegenerativas , Pleurotus , Humanos , Doenças Neurodegenerativas/tratamento farmacológico , PolissacarídeosRESUMO
Considered as the "King of spices", black pepper (Piper nigrum L.) is a widely used spice which adds flavor of its own to dishes, and also enhances the taste of other ingredients. Piper nigrum has also been extensively explored for its biological properties and its bioactive phyto-compounds. There is, however, no updated compilation of these available data to provide a complete profile of the medicinal aspects of P. nigrum. This study endeavors to systematically review scientific data on the traditional uses, phytochemical composition, and pharmacological properties of P. nigrum. Information was obtained using a combination of keywords via recognized electronic databases (e.g., Science Direct and Google Scholar). Google search was also used. Books and online materials were also considered, and the literature search was restricted to the English language. The country with the highest number of traditional reports of P. nigrum for both human and veterinary medicine was India, mostly for menstrual and ear-nose-throat disorders in human and gastrointestinal disorders in livestock. The seeds and fruits were mostly used, and the preferred mode of preparation was in powdered form, pills or tablets, and paste. Piper nigrum and its bioactive compounds were also found to possess important pharmacological properties. Antimicrobial activity was recorded against a wide range of pathogens via inhibition of biofilm, bacterial efflux pumps, bacterial swarming, and swimming motilities. Studies also reported its antioxidant effects against a series of reactive oxygen and nitrogen species including the scavenging of superoxide anion, hydrogen peroxide, nitric oxide, DPPH, ABTS, and reducing effect against ferric and molybdenum (VI). Improvement of antioxidant enzymes in vivo has also been reported. Piper nigrum also exhibited anticancer effect against a number of cell lines from breast, colon, cervical, and prostate through different mechanisms including cytotoxicity, apoptosis, autophagy, and interference with signaling pathways. Its antidiabetic property has also been confirmed in vivo as well as hypolipidemic activity as evidenced by decrease in the level of cholesterol, triglycerides, and low-density lipoprotein and increase in high-density lipoprotein. Piper nigrum also has anti-inflammatory, analgesic, anticonvulsant, and neuroprotective effects. The major bioactive compound identified in P. nigrum is piperine although other compounds are also present including piperic acid, piperlonguminine, pellitorine, piperolein B, piperamide, piperettine, and (-)-kusunokinin, which also showed biological potency. Most pharmacological studies were conducted in vitro (n = 60) while only 21 in vivo and 1 clinical trial were performed. Hence, more in vivo experiments using a pharmacokinetic and pharmacokinetic approach would be beneficial. As a conclusive remark, P. nigrum should not only be regarded as "King of spices" but can also be considered as part of the kingdom of medicinal agents, comprising a panoply of bioactive compounds with potential nutraceutical and pharmaceutical applications.
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Medicina Tradicional do Leste Asiático , Piper nigrum/química , Extratos Vegetais/farmacologia , Animais , Bases de Dados Factuais , Suplementos Nutricionais , Frutas , Humanos , Índia , Compostos Fitoquímicos/análiseRESUMO
Mangroves are unique but endangered coastal ecosystems that play a vital role in the tropical and subtropical environments. Mauritius has two species of mangroves, Bruguiera gymnorrhiza (L.) Lam. and Rhizophora mucronata Lam., growing along its coast. The mangrove rhizosphere harbours a diverse microbial community and the use of RNA-sequencing can reveal both the taxonomic composition and active biochemical functions of the complex microbial community. Metatranscriptomic study was carried out by comparing the microbial community of rhizosphere microbiomes sediments from the two mangroves species. The study also included a comparison between a natural and a man grown mangrove microbiome. Overall, samples showed predominance by Proteobacteria, Bacteroidetes and Firmicutes, with high abundance of sulphate reducers, nitrogen reducers and methanogens. Significant difference was, however, noted at both taxonomic and functional levels among the mangroves species. The data also indicate that the microbial core involved in methane, nitrogen, and sulphur metabolism consisted mainly of Burkholderiaceae, Planctomycetaceae, Rhodobacteraceae, and Desulfobacteraceae. Also, genes encoding enzymes involved in carbon cycling, the metabolism of nitrogen, methane and sulphur were dominant in the rhizosphere of the natural mangrove ecosystem. To our knowledge, this is a first metatranscriptomic study on the microbiome of mangroves in the Mauritius, and our results provide the first insights in the range of functions and microbial diversity of the local mangrove species.
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Archaea/classificação , Archaea/metabolismo , Bactérias/classificação , Bactérias/metabolismo , Ecossistema , Rhizophoraceae/microbiologia , Transcriptoma , Áreas Alagadas , Archaea/enzimologia , Archaea/genética , Bactérias/enzimologia , Bactérias/genética , Biodiversidade , Ciclo do Carbono , Sedimentos Geológicos/microbiologia , Maurício , Metano/metabolismo , Consórcios Microbianos/genética , Microbiota , Nitrogênio/metabolismo , Filogenia , RNA/isolamento & purificação , Rhizophoraceae/classificação , Rizosfera , Enxofre/metabolismoRESUMO
Botryosphaeria kuwatsukai is an important fungal pathogen affecting pear fruits. However, infection processes of this fungus are still unclear. This study seeks to develop the fungal transformation of B. kuwatsukai by Agrobacterium tumefaciens-mediated transformation (ATMT), assess the reliability of appropriate vectors and examine the infection processes in vitro using a GFP labeled strain of B. kuwatsukai. To establish a highly effective transformation system in B. kuwatsukai, binary vectors containing various lengths of H3 promoters and TEF promoters fused with GFP and hygromycin B resistance gene cassettes were constructed. These cassettes were integrated into the genomic DNA of B. kuwatsukai with high transformation frequency by the ATMT method. Transformants showed strong expression of GFP and hygromycin B resistance genes in cells. Furthermore, we investigated if native promoters are more suitable to govern marker genes than other general promoters used in other filamentous fungi. The results obtained herein demonstrate that the vectors constructed in this study can be utilized with high transformation rate. Microscopic examinations also reveal that fungal hyphae undergo morphological changes during the infection process resulting in biotrophic stage of infected host cells. Our results provide genetic insights to further explore the infection processes of B. kuwatsukai.
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Agrobacterium tumefaciens/genética , Ascomicetos/efeitos dos fármacos , Ascomicetos/genética , Higromicina B/farmacologia , Regiões Promotoras Genéticas/genética , Pyrus/microbiologia , Transformação Genética , Agrobacterium tumefaciens/metabolismo , Antibacterianos/farmacologia , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , DNA Bacteriano/genética , DNA Fúngico , Farmacorresistência Bacteriana/genética , Regulação Bacteriana da Expressão Gênica/genética , Marcadores Genéticos , Vetores Genéticos , Doenças das Plantas/prevenção & controle , VirulênciaRESUMO
Obesity is a significant public health concern affecting more than half a billion people worldwide. Obesity rise is not only limited to developed countries, but to developing nations as well. This paper aims to compare the mean body mass index trends in the World Health Organisation- (WHO-) categorised regions since 1980 to 2008 and secondly to appraise how socioeconomic disparities can lead to differences in obesity and physical activity level across developing nations. Taking into account past and current BMI trends, it is anticipated that obesity will continue to take a significant ascent, as observed by the sharp increase from 1999 to 2008. Gender differences in BMI will continue to be as apparent, that is, women showing a higher BMI trend than men. In the coming years, the maximum mean BMI in more developed countries might be exceeded by those in less developed ones. Rather than focusing on obesity at the individual level, the immediate environment of the obese individual to broader socioeconomic contexts should be targeted. Most importantly, incentives at several organisational levels, the media, and educational institutions along with changes in food policies will need to be provided to low-income populations.
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Atividade Motora , Obesidade/epidemiologia , Pobreza , Classe Social , Adulto , África/epidemiologia , América/epidemiologia , Ásia/epidemiologia , Índice de Massa Corporal , Países em Desenvolvimento , Dieta/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/economia , Obesidade/etiologiaRESUMO
Marine fungi represent an important proportion of the microbial diversity in the oceans. They are attractive candidates for biotechnological purposes and industrial applications. Despite an increasing interest in mycology, marine fungi associated with sponges and algae have been poorly studied in Mauritius. The objectives of this study were to: 1) use multigene phylogenetic analyses to identify isolated marine fungi; 2) determine the differences in the antimicrobial and antioxidant properties of the fungal extracts; and 3) assess their enzyme activities and dye decolorization potential. Five fungal isolates viz Aspergillus chevalieri, Aspergillus iizukae, Aspergillus ochraceus, Exserohilum rostratum and Biatriospora sp. were identified based on phylogenetic analyses. There was no significant difference in the antimicrobial properties of the liquid and solid media extracts unlike the antioxidant properties (p < 0.05). The solid media extract of Aspergillus chevalieri (F2-SF) had a minimum inhibitory concentration of 0.156 mg/ml against Staphylococcus aureus while Aspergillus ochraceus (F25-SF) had a minimum inhibitory concentration of 0.313 and 2.5 mg/ml against Enterococcus faecalis and Salmonella typhi. The solid media extract of Biatriospora sp. (F34-SF) had a minimum inhibitory concentration of 0.195 and 1.563 mg/ml against Bacillus cereus, Escherichia coli and Enterobacter cloacae. An IC50 of 78.92 ± 4.71 µg/ml in the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) scavenging assay, ferric reducing antioxidant power (FRAP) value of 11.17 ± 0.20 mM Fe2+/g dry weight extract (DWE) and total phenolic content 360.35 ± 10.31 mg GAE/g DWE was obtained with the solid media extract of Aspergillus chevalieri (F2-SF). Aspergillus ochraceus (F25-SF) and Biatriospora sp. (F34-SF) solid media extracts showed lower IC50 values in the DPPH assay and higher total phenolic content as compared to the liquid media extracts. Aspergillus chevalieri was a good producer of the enzymes DNAse and lipase and had maximum percentage dye decolorization of 79.40 ± 17.72% on Congo red. An enzymatic index ≥ 2 was found for the DNAse and lipase and the maximum percentage dye decolorization of 87.18 ± 3.80% was observed with Aspergillus ochraceus on Methylene blue. Regarding Biatriospora sp., it was a moderate producer of the three enzymes amylase, DNAse and protease and had a maximum dye decolorization potential of 56.29 ± 6.51% on Crystal violet. This study demonstrates that Mauritian marine fungi possess good bioactive properties, enzymatic and dye decolorization potentials, that can potentially be considered for use in pharmaceutical and industrial applications.
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Globally, breast cancer is a primary contributor to cancer-related fatalities and illnesses among women. Consequently, there is a pressing need for safe and effective treatments for breast cancer. Bioactive compounds from endophytic fungi that live in symbiosis with medicinal plants have garnered significant interest in pharmaceutical research due to their extensive chemical composition and prospective medicinal attributes. This review underscores the potentiality of fungal endophytes as a promising resource for the development of innovative anticancer agents specifically tailored for breast cancer therapy. The diversity of endophytic fungi residing in medicinal plants, success stories of key endophytic bioactive metabolites tested against breast cancer and the current progress with regards to in vivo studies and clinical trials on endophytic fungal metabolites in breast cancer research forms the underlying theme of this article. A thorough compilation of putative anticancer compounds sourced from endophytic fungi that have demonstrated therapeutic potential against breast cancer, spanning the period from 1990 to 2022, has been presented. This review article also outlines the latest trends in endophyte-based drug discovery, including the use of artificial intelligence, machine learning, multi-omics approaches, and high-throughput strategies. The challenges and future prospects associated with fungal endophytes as substitutive sources for developing anticancer drugs targeting breast cancer are also being highlighted.
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BACKGROUND: Fusarium species, a group of economically destructive phytopathogens, are poorly studied in Mauritius where agriculture holds much significance. Furthermore, the increasing popularity of organic farming has prompted interest in alternatives to chemical fungicides. METHODS: After gaining an overview of Fusarium prevalence in Mauritius fields through a survey, the pathogen was isolated from infected crops and identified based on morphological and molecular characteristics. Methanol and water extracts were then prepared from Melia azedarach, Ocimum gratissimum, cinnamon and cloves before determining their phytochemical profiles. Additionally, the antioxidant and antifungal effects of different concentrations of aqueous extracts were assessed. RESULTS: The isolate was confirmed as Fusarium oxysporum, and cloves inhibited its growth by up to 100%, especially at 60 and 90 g/L, with the results being significantly higher than those of the synthetic fungicide mancozeb. Over 50% inhibition was also noted for cinnamon and Ocimum gratissimum, and these effects could be linked to the flavonoids, phenols and terpenoids in the extracts. CONCLUSION: This study presented the aqueous extracts of cloves, cinnamon and Ocimum gratissimum as potential alternatives to chemical fungicides. It also confirmed the prevalence of Fusarium infection in Mauritius fields, thereby highlighting the need for additional studies on the pathogen.
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Background. Low calcium intake, a risk factor of osteoporosis and subsequent fractures, has been previously reported among post-menopausal women in Mauritius. Objective. To assess the effectiveness of a theory-based educational intervention in improving the calcium intake, self-efficacy, and knowledge of older Mauritians. Methodology. The study was conducted as a pre- and post-test design which was evaluated through a baseline, immediate postintervention, and 2-month follow-up assessments. Participants were adults (n = 189) aged ≥40 years old from 2 urban community-based centres. The intervention group (IG) (n = 98) participated in 6 weekly interactive lessons based on the health belief model (HBM). The main outcome measures were calcium intake, HB scale scores, knowledge scores, and physical activity level (PAL). Anthropometric measurements were also assessed. Results. The IG significantly increased its baseline calcium intake, knowledge and self-efficacy (P < 0.001) at post-assessments. A significant decrease in waist circumference in the IG was noted (P < 0.05) after intervention. PAL significantly increased by 12.3% at post-test and by 29.6% at follow-up among intervention adults when compared to the CG (P < 0.001). Conclusion. A theory-driven educational intervention is effective in improving the dietary calcium intake, knowledge, self-efficacy, and PAL of older community-based Mauritian adults.
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Cálcio da Dieta/uso terapêutico , Dietoterapia/estatística & dados numéricos , Educação em Saúde/estatística & dados numéricos , Letramento em Saúde/estatística & dados numéricos , Promoção da Saúde/estatística & dados numéricos , Osteoporose/epidemiologia , Osteoporose/prevenção & controle , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Maurício/epidemiologia , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Distribuição por SexoRESUMO
The fungal genus Microcera consists of species mostly occurring as parasites of scale insects, but are also commonly isolated from soil or lichens. In the present study, we surveyed the diversity and assess the taxonomy of entomopathogenic fungi in Sichuan Province, China. Two new species of Microcera, viz. M.chrysomphaludis and M.pseudaulacaspidis, were isolated from scale insects colonising walnut (Juglansregia). Maximum Likelihood and Bayesian Inference analyses of ITS, LSU, tef1-α, rpb1, rpb2, acl1, act, tub2, cmdA and his3 sequence data provide evidence for the validity of the two species and their placement in Nectriaceae (Hypocreales). Microcerapseudaulacaspidis primarily differs from similar species by having more septate and smaller cylindrical macroconidia, as well as DNA sequence data. Meanwhile, Microcerachrysomphaludis has elliptical, one-septate ascospores with acute ends and cylindrical, slightly curved with 4-6 septate macroconidia up to 78 µm long. Morphological descriptions with illustrations of the novel species and DNA-based phylogeny generated from analyses of multigene dataset are also provided to better understand species relationships.
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Tetraplosphaeriaceae (Pleosporales, Ascomycota) is a family with many saprobes recorded from various hosts, especially bamboo and grasses. During a taxonomic investigation of microfungi in tropical and subtropical forest regions of Guizhou, Hainan and Yunnan provinces, China, several plant samples were collected and examined for fungi. Four newly discovered species are described based on morphology and evolutionary relationships with their allies inferred from phylogenetic analyses derived from a combined dataset of LSU, ITS, SSU, and tub2 DNA sequence data. Detailed illustrations, descriptions and taxonomic notes are provided for each species. The four new species of Tetraplosphaeriaceae reported herein are Polyplosphaeriaguizhouensis, Polyplosphaeriahainanensis, Pseudotetraploayunnanensis, and Tetraploahainanensis. A checklist of Tetraplosphaeriaceae species with available details on their ecology is also provided.
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There are no documented studies on socioeconomic status (SES) and body mass index (BMI) among Mauritian adolescents. This study aimed to determine the relationships between SES and BMI among adolescents with focus on diet quality and physical activity (PA) as mediating factors. Mauritian school adolescents (n = 200; 96 males, 104 females) were recruited using multistage sampling. Participants completed a self-reported questionnaire. Height and weight were measured and used to calculate BMI (categorised into underweight, healthy-weight, overweight, obese). Chi-square test, Pearson correlation, and Independent samples t-test were used for statistical analysis. A negative association was found between SES and BMI (χ(2) = 8.15%, P < 0.05). Diet quality, time spent in PA at school (P = 0.000), but not total PA (P = 0.562), were significantly associated with high SES. Poor diet quality and less time spent in PA at school could explain BMI discrepancies between SES groups.
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Desenvolvimento do Adolescente/fisiologia , Índice de Massa Corporal , Classe Social , Adolescente , Comportamento do Adolescente/fisiologia , Comportamento do Adolescente/psicologia , Fenômenos Fisiológicos da Nutrição do Adolescente , Criança , Dieta/efeitos adversos , Dieta/economia , Comportamento Alimentar/psicologia , Feminino , Humanos , Masculino , Maurício/epidemiologia , Atividade Motora , Obesidade/epidemiologia , Obesidade/psicologia , Sobrepeso/epidemiologia , Sobrepeso/psicologia , Instituições Acadêmicas , Inquéritos e Questionários , Magreza , Fatores de TempoRESUMO
There is a critical need to develop animal models to alleviate vaccine and drug development difficulties against zoonotic viral infections. The coronavirus family, which includes severe acute respiratory syndrome coronavirus 1 and severe acute respiratory syndrome coronavirus 2, crossed the species barrier and infected humans, causing a global outbreak in the 21st century. Because humans do not have pre-existing immunity against these viral infections and with ethics governing clinical trials, animal models are therefore being used in clinical studies to facilitate drug discovery and testing efficacy of vaccines. The ideal animal models should reflect the viral replication, clinical signs, and pathological responses observed in humans. Different animal species should be tested to establish an appropriate animal model to study the disease pathology, transmission and evaluation of novel vaccine and drug candidates to treat coronavirus disease 2019. In this context, the present review summarizes the recent progress in developing animal models for these two pathogenic viruses and highlights the utility of these models in studying SARS-associated coronavirus diseases.
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In the present study, we report two new asexual fungal species (i.e., Discosia rhododendricola, Neopestalotiopsis rhododendricola (Sporocadaceae) and a new host for a previously described species (i.e., Diaporthe nobilis; Diaporthaceae). All species were isolated from Rhododendron spp. in Kunming, Yunnan Province, China. All taxa are described based on morphology, and phylogenetic relationships were inferred using a multigenic approach (LSU, ITS, RPB2, TEF1 and TUB2). The phylogenetic analyses indicated that D. rhododendronicola sp. nov. is phylogenetically related to D. muscicola, and N. rhododendricola sp. nov is related to N. sonnaratae. Diaporthe nobilis is reported herein as a new host record from Rhododendron sp. for China, and its phylogeny is depicted based on ITS, TEF1 and TUB2 sequence data.
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Marine fungi are largely associated with second most inhabitants of the marine ecosystem such as sponges and algae. They are important colonizers and play vital ecological roles, such as nutrient cycling, organic matter decomposition, and symbiosis with other organisms. High throughput sequencing methods have been used successfully to reveal unknown fungal communities associated with a number of hosts particularly in the marine environment. However, the diversity of marine fungi associated with sponges and brown algae in Mauritius remains largely unknown. Traditional methods based on culturing do not provide reliable estimate of fungal diversity as only those that are able to grow under laboratory conditions are dominant; in addition, a large proportion of fungi, cultured in vitro remain most of the time unidentifiable, given that there are no sporulating structures to be examined morphologically. To overcome these limitations, we employed Illumina sequencing to unravel fungi species present in the sponges, Iotrochota sp. and Biemna sp. and the brown algae Turbinaria conoides, Sargassum pfeifferae, and Sargassum obovatum, collected from the north of Mauritius. Diversity analyses revealed that Biemna sp. had the highest diversity from the sampled sponges with fungi from 24 orders being recovered while from brown algae; Turbinaria conoides had the highest diversity with recovery of fungal taxa of the orders Botryosphaeriales, Chaetothyriales, Eurotiales, Hypocreales, and Mucorales with the latter four orders being common in both sampled algae and sponges. Beta diversity analyses revealed clustering only in the algae, Turbinaria conoides, and Sargassum pfeifferae and not in the co-occurring sponges, indicating that sampling location did not have much influence on fungal diversity. Our findings provide the first amplicon sequencing based insights of the fungal communities associated with macro-algae and sponges in Mauritius and supplements research on the fungal community existing in the oceans around the world.
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During our survey into the diversity of woody litter fungi across the Greater Mekong Subregion, three rhytidhysteron-like taxa were collected from dead woody twigs in China and Thailand. These were further investigated based on morphological observations and multi-gene phylogenetic analyses of a combined DNA data matrix containing SSU, LSU, ITS, and tef1-α sequence data. A new species of Rhytidhysteron, R.xiaokongense sp. nov. is introduced with its asexual morph, and it is characterized by semi-immersed, subglobose to ampulliform conidiomata, dark brown, oblong to ellipsoidal, 1-septate, conidia, which are granular in appearance when mature. In addition to the new species, two new records from Thailand are reported viz. Rhytidhysterontectonae on woody litter of Betula sp. (Betulaceae) and Fabaceae sp. and Rhytidhysteronneorufulum on woody litter of Tectonagrandis (Lamiaceae). Morphological descriptions, illustrations, taxonomic notes and phylogenetic analyses are provided for all entries.
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Botryosphaeriaceous fungi cause stem blight, canker and dieback in woody plants. During a survey on the fungal pathogens associated with blueberries in China, 135 blighted, cankered or dead blueberry branches were collected from Fujian and Shandong Provinces. Based on the morphological characterization and phylogenetic analyses of a concatenated ITS rDNA, tef1-α, TUB, and RPB2 loci, five new species of Lasiodiplodia, viz., L. clavispora, L. fujianensis, L. henanica, L. nanpingensis and L. paraphysoides were recognized. Detailed descriptions and illustrations, as well as multigene phylogenies, are provided in this paper. The diversity of plant pathogens on agriculturally and economically important plants is higher than anticipated.