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1.
Int J Mol Sci ; 24(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37833975

RESUMO

Continuous microwave-assisted flow synthesis has been used as a simple, more efficient, and low-cost route to fabricate a range of nanosized (<100 nm) strontium-substituted calcium phosphates. In this study, fine nanopowder was synthesized via a continuous flow synthesis with microwave assistance from the solutions of calcium nitrate tetrahydrate (with strontium nitrate as Sr2+ ion source) and diammonium hydrogen phosphate at pH 10 with a time duration of 5 min. The morphological characterization of the obtained powder has been carried out by employing techniques such as transmission electron microscopy, X-ray diffraction, and Brunauer-Emmett-Teller surface area analysis. The chemical structural analysis to evaluate the surface properties was made by using X-ray photoelectron spectroscopy. Zeta potential analysis was performed to evaluate the colloidal stability of the particles. Antimicrobial studies were performed for all the compositions using four bacterial strains and an opportunistic human fungal pathogen Macrophomina phaseolina. It was found that the nanoproduct with high strontium content (15 wt% of strontium) showed pronounced antibacterial potential against M. luteus while it completely arrested the fungal growth after 48 h by all of its concentrations. Thus the synthesis strategy described herein facilitated the rapid production of nanosized Sr-substituted CaPs with excellent biological performance suitable for a bone replacement application.


Assuntos
Anti-Infecciosos , Nanoestruturas , Humanos , Cálcio/química , Fosfatos de Cálcio/farmacologia , Fosfatos de Cálcio/química , Regeneração Óssea , Cálcio da Dieta , Estrôncio/farmacologia , Estrôncio/química , Anti-Infecciosos/farmacologia , Difração de Raios X
2.
RSC Adv ; 13(32): 22268-22280, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37492507

RESUMO

Curcumin is an extensively studied natural compound due to its extensive biological applications. However, there are some drawbacks linked to this compound such as poor absorption, low water-solubility, quick systemic elimination, fast metabolism, poor pharmacokinetics, low bioavailability, low penetration targeting efficacy and low stability. To overcome these drawbacks, curcumin is encapsulated in nano-carriers. In the current studies, we synthesized nanoparticles of curcumin without using nanocarriers by different methods such as nano-suspension (Cur-NSM), sonication (Cur-SM) and anti-solvent precipitation (Cur-ASP) to enhance the solubility of curcumin in water. The prepared nanoparticles were characterized by FTIR, SEM and XRD analysis. These curcumin nanoparticles were screened for their solubilities in water, DPPH scavenging, amylase, α-glucosidase and ß-glucosidase enzymatic activities. The particle size of nano-curcumin was found to be in the 47.4-98.7 nm range. The reduction in particle size of curcumin dramatically increases its solubility in water to 79.2 µg mL-1, whereas the solubility of curcumin is just 0.98 µg mL-1. Cur-ASP showed the highest free radical scavenging potential (48.84 ± 0.98%) which was comparable with standard BHT (50.48 ± 1.11%) at 75.0 µg mL-1. As well, Cur-ASP showed the highest inhibition of α-amylase (68.67 ± 1.02%), α-glucosidase (58.30 ± 0.52%), and ß-glucosidase (64.80 ± 0.43%) at 100 µg mL-1 which is comparable with standard drug acarbose. The greater surface area of nanoparticles exposes the various groups of curcumin for blocking the binding sites of enzymes. This strategy may be helpful in designing curcumin as a potent therapeutic agent against diabetes mellitus. Further, the molecular interactions of curcumin with α-amylase, α-glucosidase, ß-glucosidase, and polyphenol oxidase were assessed by analyzing the plausible binding modes of curcumin in the binding pocket of each receptor. The best binding mode of curcumin was used to make complexes with the target proteins and their stability was confirmed by 50 ns MD simulation.

3.
Sci Rep ; 12(1): 20952, 2022 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-36471116

RESUMO

Contamination of agricultural soil with chromium (Cr) ions has threatened global crop, human and ecosystem health. Its two oxidation states viz. Cr(III) and Cr(VI) are most stable and readily available to the plants. The study explored the impact of increasing exposure (up to 500 ppm) of Cr(III) and Cr(VI) on bio-physical traits of 15-day-old seedlings (in vitro) as well as 60-day-old tomato plant (in vivo), and highlighted the importance of buffel grass (Cenchrus pennisetiformis) in mitigating Cr levels in the tomato plants. In vitro, Petri plate bioassays with 13 different concentrations (20-500 ppm) of Cr(III) and Cr(VI) depicted the highly toxic effect of metal ions ≥ 200 ppm on all bio-physical traits of tomato seedlings. In vivo, soil spiked with Cr(III) and Cr(VI) (200, 300, and 400 mg/kg) was amended with 1% and 2% dry biomass of buffel grass. Phytotoxicity was higher in Cr(VI)-spiked soil compared with Cr(III)-spiked soil. Cr was mainly accumulated in tomato roots, and more Cr was translocated from roots to shoots from Cr(VI)-spiked soil than Cr(III)-spiked soil. Soil amendments with 2% weed biomass reduced metal toxicity in plants, particularly at 200 and 300 mg/kg of Cr. Protein profiles through SDS-PAGE revealed 12-50 kDa (mainly PR proteins) as an important region in tomato leaf, where many new bands were expressed under different treatments, particularly in the treatments provided with buffel grass. PCA-based biplot clearly separated Cr tolerance treatments from highly sensitive treatments. For the cultivation of tomato plants in Cr(III) and Cr(VI) contaminated soil (200 and 300 mg/kg), the biomass of Cloncurry buffel grass should be considered an effective and easily available phyto-management option.


Assuntos
Cenchrus , Poluentes do Solo , Solanum lycopersicum , Humanos , Solanum lycopersicum/metabolismo , Poluentes do Solo/metabolismo , Ecossistema , Cromo/metabolismo , Solo , Plantas/metabolismo , Raízes de Plantas/metabolismo
4.
RSC Adv ; 12(37): 23963-23972, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36093243

RESUMO

An eco-friendly simple protocol has been devised for the preparation of coumarin derivatives using doubly Brønsted acidic task specific ionic liquid (TSIL) as a catalyst. Solvent-free conditions were employed for the reaction of different substituted phenols with ß-ketoester in TSIL to produce corresponding substituted coumarin derivatives in good to excellent yields at ambient conditions; at room temperature and with reduced reaction times. The ionic liquid catalyst can be recycled and reused up to five times. All the synthesized coumarins were evaluated for their antifungal activities against Macrophomina phaseolina, a plant as well as an opportunistic human pathogenic fungus affecting more than 500 plant species worldwide and with no registered commercial fungicide available against it, to date. Amongst all the coumarins tested, compounds 3f and 3i showed excellent antifungal activity comparable to reference fungicide mancozeb. The current methodology provides an easy and expedient way to access the coumarin core in search of potential fungicides for sustainable agriculture.

5.
Braz J Microbiol ; 53(3): 1613-1621, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35831780

RESUMO

The present study was carried out to evaluate the antagonistic efficacy of Aspergillus versicolor against the soil and seed inhibiting destructive plant pathogen Macrophomina phaseolina. The tested antagonist was confirmed by rDNA sequencing of ITS and ß-tubulin genes with respective accession numbers MN719083 and MN736397. In dual culture bioassays, A. versicolor showed potent antagonist activity and reduced the pathogen's growth by 60% over control. To understand the mechanism of antagonistic fungus, DNA of the pathogenic fungus was incubated in secondary metabolites produced by the A. versicolor for 24 and 48 h. After 48 h, metabolites of A. versicolor fully degraded the DNA of M. phaseolina. Moreover, for the identification of bioactive compounds, the chloroform and ethyl acetate fractions of A. versicolor culture filtrates were subjected to GC-MS analysis. A total of 10 compounds were identified in each of the two fractions. Among these, chondrillasterol (37.43%) followed by 1,2-benzedicarboxylic acid, diisooctyl ester (25.93%), decane (16.63%), 9,12-octadecadienoic acid (Z,Z)- (13.32%), stigmasterol (11.16%), undecane (10.93%), cis-1-chloro-9-octadecene (8.66%), benzene, 1,3,5-trimethyl (8.46%), and hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester (8.13%) were the major compounds. Some of the identified compounds are known to possess strong antifungal, antibacterial, nematicidal, and antioxidant properties. The present study concludes that A. versicolor is an effective antagonist against M. phaseolina.


Assuntos
Ascomicetos , Aspergillus/genética , Ésteres , Doenças das Plantas/microbiologia
6.
Microsc Res Tech ; 85(8): 2953-2964, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35510761

RESUMO

In the present study, two Aspergillus species as biocontrol agents together with Chenopodium quinoa dry biomass were used to investigate their effects on histochemical features of mungbean plant inoculated with M. phaseolina. In a pot experiment, Aspergillus flavipes and Aspergillus versicolor were added either alone or together with 1%, 2%, and 3% dry biomass of quinoa (DBQ) to the pot soil already inoculated with M. phaseolina. After 4 weeks of sowing, root and lower-stem sections of the mungbean plants were stained with ferric chloride, phloroglucinol-HCl and Lugol's iodine to detect the presence of polyphenols, lignin, and starch granules, respectively, and observed under light microscope. Stem and root sections were also observed under scanning electron microscope (SEM) to reveal the effect of soil amendments on cell structures. The findings revealed that mungbean plant cross sections from all the treatments except positive control (only inoculated with M. phaseolina) showed very clear cell structures. In positive control, distorted, fragmented, and collapsed cell structures were observed. Moreover, M. phaseolina blocked vascular vessels in comparison to negative control where the cell structures were intact and normal in size. Plant sections from treatments with A. flavipes and A. versicolor alone or together with DBQ were without pathogen colonization, with normal cell structures and a high deposition of gel. The results suggested that the two Aspergillus spp. and C. quinoa induced defense responses in mungbean plants. HIGHLIGHTS: Macrophomina phaseolina causes significant yield losses in mungbean. Pot soil was amended with two species of Aspergillus as biocontrol agents along with plant biomass. Aspergillus spp. markedly saved the root and stem structures from the damage caused by M. phaseolina.


Assuntos
Fabaceae , Vigna , Aspergillus , Biomassa , Doenças das Plantas/prevenção & controle , Solo
7.
Microsc Res Tech ; 85(7): 2596-2606, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35366387

RESUMO

Mungbean production is affected by a fungal pathogen Macrophomina phaseolina. A pot experiment was carried out to check the effect of quinoa (Chenopodium quinoa Willd.) dry biomass on the histopathological features of mungbean exposed to M. phaseolina. For this, 1%, 2% and 3% (wt/wt) of C. quinoa dry biomass was mixed in the soil inoculated with M. phaseolina. The highest disease incidence (36%) was recorded in the positive control (only M. phaseolina). Different treatments of quinoa dry mass reduced disease incidence to 4-7%. After 4 weeks of germination, stem and root sections were stained in phloroglucinol-HCl, ferric chloride and Lugol's iodine stains for the detection of lignin, polyphenols and starch granules, respectively, and studied under light microscope. Plants of positive control showed damaged cells, and heavy deposition of lignin, phenolics and starch granules as compared to plants of the negative control and those grown in the soil amended with different doses of dry biomass of quinoa. For better understanding, plant root and stem sections were studied under a scanning electron microscope. Plant sections from positive control exhibited the presence of M. phaseolina sclerotial bodies and hyphal growth, whereas in negative control normal cell structures were observed. However, C. quinoa amended stem and root sections revealed the presence of high gel deposition with normal cell structures and no pathogen establishment. This study concludes that application of C. quinoa is an effective and natural remedy to activate the resistance mechanism in plants and to combat the adverse effects of M. phaseolina. HIGHLIGHTS: Macrophomina phaseolina causes charcoal rot in mungbean. Chenopodium quinoa amendment significantly reduced incidence of charcoal rot disease. M. phaeolina increased concentrations of polyphenols, lignin and starch granules in mungbean.


Assuntos
Chenopodium quinoa , Fabaceae , Vigna , Ascomicetos , Biomassa , Lignina , Doenças das Plantas/microbiologia , Polifenóis , Solo , Amido
8.
Mycologia ; 114(1): 24-34, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34928190

RESUMO

In the present study, five Penicillium species, namely, P. italicum, P. expansum, P. simplicissimum, P. oxalicum, and P. citrinum, were identified using ITS (internal transcribed spacer) and ß-tubulin markers and screened for their in vitro antagonistic potential against a soil-borne fungal pathogen, Macrophomina phaseolina, in a dual-culture plate assay. Among all the tested strains, P. italicum showed the highest antagonistic potential against M. phaseolina by reducing its growth up to 57% over control, followed by P. citrinum (42%), P. simplicissimum (21%), P. expansum (11%), and P. oxalicum (9%). In order to find out the mechanism of action of P. italicum, genomic DNA of M. phaseolina was exposed to P. italicum secondary metabolites. The findings showed that these metabolites completely degraded the fungal DNA after the 48-h incubation period. To further explore the antifungal mechanism of action of P. italicum, chloroform and ethyl acetate fractions of its metabolites were subjected to gas chromatography-mass spectrometry (GC-MS) analysis. The major compounds identified in these fractions were 9,12-octadecadienoic acid (Z,Z)- (25.19%), decane (19.72%), dodecane (18.05%), benzene, nitro- (14.62%), benzene, 1,3,5-trimethyl (14.37%), benzene, 1,4-diethyl (11.62%), 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester (9.02%), and 1-nonadecene (8.99%), which could be responsible for control of M. phaseolina growth.


Assuntos
Antifúngicos , Penicillium , Antifúngicos/farmacologia , Ascomicetos , Benzeno , Clivagem do DNA , Doenças das Plantas/microbiologia , Doenças das Plantas/prevenção & controle
9.
Physiol Mol Biol Plants ; 27(6): 1361-1376, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34177151

RESUMO

The fungal pathogen, Alternaria alternata is responsible for causing leaf spot disease in many plants, including chili pepper. Zinc (Zn) an essential micronutrient for plant growth, also increases resistance in plants against diseases, and also acts as an antifungal agent. Here, in vitro effects of ZnSO4 on the propagation of A. alternata were investigated, and also in vivo, the effect of foliar application of ZnSO4 was investigated in chili pepper plants under disease stress. In vitro, ZnSO4 inhibited fungal growth in a dose-dependent manner, with complete inhibition being observed at the concentration of 8.50 mM. Hyphae and conidial damage were observed along with abnormal activity of antioxidant enzymes, Fourier-transform infrared spectroscopy confirmed the major changes in the protein structure of the fungal biomass after Zn accumulation. In vivo, pathogen infection caused the highest leaf spot disease incidence, and cumulative disease index, which resulted in a significant reduction in the plant's growth (length and biomass), and physiochemical traits (photosynthetic pigment, activity of catalase, peroxidase, polyphenol oxidase, and phenylalanine ammonia lyase). The heat map and principal component analysis based on disease, growth and, physico-chemical variables generated useful information regarding the best treatment useful for disease management. Foliar Zn (0.036 mM) acted as a resistance inducer in chili pepper plants that improved activities of antioxidants (CAT and POX), and defense compounds (PPO and PAL), while managing 77% of disease. The study indicated foliar ZnSO4 as an effective and sustainable agriculture practice to manage Alternaria leaf spot disease in chili pepper plants.

10.
Cureus ; 13(4): e14684, 2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-34055529

RESUMO

Introduction Interstitial lung disease (ILD) is a heterogeneous group of over 200 parenchymal lung diseases with a myriad of etiologies. Interstitial lung disease registries from around the world show varying prevalence and incidence of these diseases. The aim of this study was to determine the epidemiology and characteristics of ILD in Pakistan. Methods This web-based registry, which is the first multicenter registry of ILD from Pakistan, recruited patients from 10 centers of five major cities between January 2016 and March 2019. Results A total of 744 patients were enrolled in the registry. The five most frequent ILDs were idiopathic pulmonary fibrosis (IPF) 34.4%, hypersensitivity pneumonitis (HP) - 17.7%, idiopathic nonspecific interstitial pneumonitis (iNSIP) - 16.8%, connective tissue disease-associated ILD (CTD-ILD) - 16.3%, and sarcoidosis - 9.1%. Conclusion Idiopathic pulmonary fibrosis is the most prevalent ILD in Pakistan, followed by HP and iNSIP. An ongoing prospective registry with longitudinal follow-up will help us further elaborate on the clinical characteristics, treatment, and survival outcome of patients with ILD.

11.
Microsc Res Tech ; 84(11): 2737-2748, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34028133

RESUMO

Rapid advances in the field of pathogen detection have opened new opportunities and better understanding for their management approaches. Aim of this study was to elucidate histopathological observations of different tissues affected by Macrophomina phaseolina and to observe the defense responses of plant growth promoting rhizobacteria (PGPR) in mungbean plants. Sections of the stem and root were prepared and stained with ferric chloride, Lugol's iodine and Wiesner's reagent and were then observed under multiple microscopic techniques. Results revealed that both pathogen and PGPR produce responses on the plant that include colonization of xylem vessels by hyphae and sclerotia, hypertrophy and hyperplasia of the cells, destruction of xylem fibers and amyloplasts in parenchymatous cells; and production of gels by the plant were observed. There was a significant increase in lignin and phenolic compounds deposition in stem and root sections of PGPR treated and non-treated mungbean plants. Whereas the soil amended with PGPR showed very less to no starch production. Moreover, production of gels and gums were also observed in both stem and root sections. Compared to light microscopy, scanning electron microscope provided greater depth of focus and resolution of the pathogen attack on plant tissues, associated bacteria. As a whole, the data demonstrated that inoculation of PGPR can be an effective strategy to stimulate plant growth and they could significantly activate disease resistance against M. phaseolina.


Assuntos
Vigna , Ascomicetos , Fungos , Raízes de Plantas , Plantas , Solo
12.
Sci Rep ; 11(1): 8417, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33875698

RESUMO

Antifungal activity of Monotheca buxifolia methanolic extract and its various fractions were assessed against Macrophomina phaseolina, a soil-borne fungal pathogen of more than 500 vegetal species as well as rare and emerging opportunistic human pathogen. Different concentrations of methanolic extract (3.125 to 200 mg mL-1) inhibited fungal biomass by 39-45%. Isolated n-hexane, chloroform and ethyl acetate fractions suppressed fungal biomass by 32-52%, 29-50% and 29-35%, respectively. Triterpenes lupeol and lupeol acetate (1, 2) were isolated from n-hexane while betulin, ß-sitosterol, ß-amyrin, oleanolic acid (3-6) were isolated from chloroform fraction. Vanillic acid, protocatechuic acid, kaempferol and quercetin (7-10) were isolated from the ethyl acetate fraction and identified using various spectroscopic techniques namely mass spectroscopy and NMR. Antifungal activity of different concentrations (0.0312 to 2 mg mL-1) of the isolated compounds was evaluated and compared with the activity of a broad spectrum fungicide mancozeb. Different concentrations of mencozeb reduced fungal biomass by 83-85%. Among the isolated compounds lupeol acetate (2) was found the highest antifungal against M. phaseolina followed by betulin (3), vanillic acid (7), protocatechuic acid (8), ß-amyrin (5) and oleanolic acid (6) resulting in 79-81%, 77-79%, 74-79%, 67-72%, 68-71% and 68-71%, respectively. Rest of the compounds also showed considerable antifungal activity and reduced M. phaseolina biomass by 41-64%.


Assuntos
Ascomicetos/efeitos dos fármacos , Micoses/tratamento farmacológico , Triterpenos Pentacíclicos/farmacologia , Antifúngicos/farmacologia , Humanos , Maneb/farmacologia , Infecções Oportunistas/tratamento farmacológico , Extratos Vegetais/farmacologia , Zineb/farmacologia
13.
Int J Biol Macromol ; 178: 253-262, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636267

RESUMO

The present study demonstrated that chitin-based nanofibers (CNFs) trigger the chitinase genes (PGIP1 and CaChi2), while elevating salicylic acid that can protect plants against pathogens. Cross-talk between this genetic induction and salicylic-acid-mediated immune response was also observed, which may arm a plant against multiple pathovars. Crab and mushroom based CNFs were synthesized by electrospinning and ball milling techniques. Plants (mung bean, Vigna radiata) (pepper, Capsicum annuum) were pre-inoculated with CNFs and treated with the pathogens Scrolotium rolfsii for pepper and Macrophomina phaseolina for mung bean and shrimp-based CNFs were used as a control. Treated plants had elevated levels of chitinase genes in response to CNFs at inoculation concentrations <10 mg/mL both in soil and media, to protect them against the pathogenic fungal disease. After 24 h of exposure to the pathogens, qRT-PCR showed genes class II chitinase gene (CaChi2) and polygalacturonase inhibitor protein 1 (PGIP1) to be up-regulated in both root and shoot at 0.1 and 1 mg/mL of inoculation, respectively. The ball milled mushroom CNFs were sufficient to trigger the membrane based enzymes with less diameter (≥15 nm) to be most efficient versus others. In vitro analysis showed IC50 of ball milled mushroom CNFs to be most efficient in limiting the growth of fungal biomass. Further trigger-like effects were prominent in reducing pathogenic fungal spread in both species.


Assuntos
Ascomicetos/imunologia , Capsicum , Membrana Celular , Quitina , Nanofibras/química , Doenças das Plantas , Imunidade Vegetal/efeitos dos fármacos , Vigna , Capsicum/imunologia , Capsicum/microbiologia , Membrana Celular/imunologia , Membrana Celular/microbiologia , Quitina/química , Quitina/farmacologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Vigna/imunologia , Vigna/microbiologia
14.
Physiol Mol Biol Plants ; 26(7): 1385-1397, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32647456

RESUMO

Role of rhizobacteria and zinc (Zn) was investigated in the management of charcoal rot disease in mungbean [Vigna radiata (L.) Wilczek] caused by Macrophomina phaseolina (Tassi) Goid. In vitro, screening tests with eight rhizobacteria [Bacillus subtilis (FCBP-0324), B. subtilis (FCBP-0189), Rhizobacter daucus (FCBP-0450), Azospirillum brasilense (FCBP-0025), Azospirillum lipoferum (FCBP-0022), Pseudomonas malophilia (FCBP-0099), Pseudomonas florescense (FCBP-0083) and Ochrobactrum ciceri (FCBP-0727)] were conducted against M. phaseolina and FCBP-0727 were found as the most effective biocontrol agent. Molecular analyses of 16S rDNA combined with cultural and biochemical analyses confirmed FCBP-0727 identification (GeneBank Accession No. LC415039). Cell-free culture filtrate (CFCF) and cell culture of O. ciceri were separated and antifungal trials of both substrates indicated inhibition in mycelial growth and suppression in sclerotia formation, although the CFCF appeared to be more destructive against the pathogen. Ethyl-acetate and chloroform extracts of bacterial secondary metabolites completely halted the growth of M. phaseolina. The GC-MS analysis of CFCF of chloroform extract proved to be rich sources of bioactive fungicide like phthalates, adipic acid, propanoic acid, and linoleic acid. Likewise, CFCF of ethyl acetate also exhibited important organic compounds like phthalates, diisopropylglycol and octasiloxan. Pot experiment revealed that soil inoculation with O. ciceri in combination with Zn (2.5 mg/kg) protected mungbean plants against M. phaseolina through improving photosynthetic pigment, total protein content and activities of antioxidant enzymes (catalase, peroxidase and polyphenol oxidase). The present study will open new vistas for biological management of charcoal rot disease of mungbean using a combination of rhizobacteria and Zn.

15.
BMJ Open ; 10(6): e036468, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32554728

RESUMO

INTRODUCTION: South Asia is home to more than 300 million smokeless tobacco (ST) users. Bangladesh, India and Pakistan as signatories to the Framework Convention for Tobacco Control (FCTC) have developed policies aimed at curbing the use of tobacco. The objective of this study is to assess the compliance of ST point-of-sale (POS) vendors and the supply chain with the articles of the FCTC and specifically with national tobacco control laws. We also aim to assess disparities in compliance with tobacco control laws between ST and smoked tobacco products. METHODS AND ANALYSIS: The study will be carried out at two sites each in Bangladesh, India and Pakistan. We will conduct a sequential mixed-methods study with five components: (1) mapping of ST POS, (2) analyses of ST samples packaging, (3) observation, (4) survey interviews of POS and (5) in-depth interviews with wholesale dealers/suppliers/manufacturers of ST. We aim to conduct at least 300 POS survey interviews and observations, and 6-10 in-depth interviews in each of the three countries. Data collection will be done by trained data collectors. The main statistical analysis will report the frequencies and proportions of shops that comply with the FCTC and local tobacco control policies, and provide a 95% CI of these estimates. The qualitative in-depth interview data will be analysed using the framework approach. The findings will be connected, each component informing the focus and/or design of the next component. ETHICS AND DISSEMINATION: Ethical approvals for the study have been received from the Health Sciences Research Governance Committee at the University of York, UK. In-country approvals were taken from the National Bioethics Committee in Pakistan, the Bangladesh Medical Research Council and the Indian Medical Research Council. Our results will be disseminated via scientific conferences, peer-reviewed research publications and press releases.


Assuntos
Comércio/legislação & jurisprudência , Tabaco sem Fumaça/legislação & jurisprudência , Bangladesh , Humanos , Índia , Estudos Multicêntricos como Assunto , Paquistão , Projetos de Pesquisa
16.
J Pak Med Assoc ; 70(5): 803-808, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32400731

RESUMO

OBJECTIVE: To identify and explore medical students' perceptions about their academic failure. METHODS: The qualitative study was conducted at Shifa College of Medicine, Islamabad, Pakistan, from December 2016 to January 2017, and comprised medical students. Two focus group discussions and 5 semi-structured interviews were conducted with students who had obtained <50% marks in their first professional examinations. Key words and important points in the written text were highlighted, coded, themed and categorised. Data was analysed manually. RESULTS: There were 22 students in the two focus group discussions; 13(59%) males and 9(41%) females. Of the 5 interviewees, 3(60%) were males and 2(40%) were females. Variable factors related to failure ranged from curriculum, assessment, environment, educators and personal factors to issues relating to stress and time management, learning resources, financial support, living away from home, poor attendance, peer pressure during small group discussions and indoctrination by parents. CONCLUSIONS: Both personal and environmental factors were found to be affecting academic performance of medical students.


Assuntos
Desempenho Acadêmico , Sucesso Acadêmico , Educação de Graduação em Medicina , Estresse Psicológico , Estudantes de Medicina , Desempenho Acadêmico/psicologia , Desempenho Acadêmico/normas , Adulto , Currículo , Educação de Graduação em Medicina/métodos , Educação de Graduação em Medicina/organização & administração , Educação de Graduação em Medicina/normas , Meio Ambiente , Docentes de Medicina , Feminino , Grupos Focais , Humanos , Individualidade , Masculino , Paquistão , Percepção Social , Estresse Psicológico/etiologia , Estresse Psicológico/psicologia , Estudantes de Medicina/psicologia , Estudantes de Medicina/estatística & dados numéricos
17.
Pak J Pharm Sci ; 33(5): 2103-2111, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33824119

RESUMO

Nigella sativa is an extensively utilized herbal medicinal plant. Medicinal utilization of seeds and oil of N. sativa was common among all the ancient medicinal systems. Previously, the vegetative part of the plant was not utilized for pharmaceutical purposes. Therefore, the current study was aimed at determining the potential of the vegetative parts (leaves, branches and stem) of the plant to reduce the pressure on the reproductive part (seeds/oil) and to get a potential alternate source of pharmaceutical materials. The experiment was carried out in split block RCD design. The dried plant was extracted through partitioning method in a series of concentrations ranging from 200-1.562mg/ml in different solvents. Phyto-chemical screening, antibacterial and anti-oxidant assays and GC-MS analysis of the potent extracts were done. The green parts of N. sativa were shown to contain saponins, alkaloids, terpenoids, steroids, cardiac glycosides, tannins, and flavonoids, whereas phloba-tannins were absent. Evaluation of anti-aging properties through antioxidant assays yielded significant results in all the assays. Linoleic acid, palmitic acid, stearic acid, oleic acid and glyceryl linoleate were profiled through GC-MS analysis. Based on these results, it was concluded that the vegetative parts of N. sativa are effective alternatives to the reproductive part/seed for anti-aging and other phytochemicals needed to meet the present day requirements of the pharmaceutical industry.


Assuntos
Antibacterianos/isolamento & purificação , Antioxidantes/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Nigella sativa/química , Compostos Fitoquímicos/isolamento & purificação , Componentes Aéreos da Planta/química , Extratos Vegetais/isolamento & purificação , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Nigella sativa/anatomia & histologia , Estresse Oxidativo/efeitos dos fármacos , Farmacognosia , Compostos Fitoquímicos/farmacologia , Componentes Aéreos da Planta/anatomia & histologia , Extratos Vegetais/farmacologia , Folhas de Planta/química , Caules de Planta/química , Sementes/química
18.
Infect Drug Resist ; 12: 2311-2322, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440067

RESUMO

OBJECTIVE: Forecasting the seasonality and trend of pulmonary tuberculosis is important for the rational allocation of health resources; however, this foresting is often hampered by inappropriate prediction methods. In this study, we performed validation research by comparing the accuracy of the autoregressive integrated moving average (ARIMA) model and the back-propagation neural network (BPNN) model in a southeastern province of China. METHODS: We applied the data from 462,214 notified pulmonary tuberculosis cases registered from January 2005 to December 2015 in Jiangsu Province to modulate and construct the ARIMA and BPNN models. Cases registered in 2016 were used to assess the prediction accuracy of the models. The root mean square error (RMSE), mean absolute percentage error (MAPE), mean absolute error (MAE) and mean error rate (MER) were used to evaluate the model fitting and forecasting effect. RESULTS: During 2005-2015, the annual pulmonary tuberculosis notification rate in Jiangsu Province was 56.35/100,000, ranging from 40.85/100,000 to 79.36/100,000. Through screening and comparison, the ARIMA (0, 1, 2) (0, 1, 1)12 and BPNN (3-9-1) were defined as the optimal fitting models. In the fitting dataset, the RMSE, MAPE, MAE and MER were 0.3901, 6.0498, 0.2740 and 0.0608, respectively, for the ARIMA (0, 1, 2) (0, 1, 1)12 model, 0.3236, 6.0113, 0.2508 and 0.0587, respectively, for the BPNN model. In the forecasting dataset, the RMSE, MAPE, MAE and MER were 0.1758, 4.6041, 0.1368 and 0.0444, respectively, for the ARIMA (0, 1, 2) (0, 1, 1)12 model, and 0.1382, 3.2172, 0.1018 and 0.0330, respectively, for the BPNN model. CONCLUSION: Both the ARIMA and BPNN models can be used to predict the seasonality and trend of pulmonary tuberculosis in the Chinese population, but the BPNN model shows better performance. Applying statistical techniques by considering local characteristics may enable more accurate mathematical modeling.

19.
J Coll Physicians Surg Pak ; 29(9): 860-864, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31455482

RESUMO

OBJECTIVE: To determine if there was any significant difference in scores of students who acquired knowledge through team-based learning (TBL) versus those who learned through small group discussion (SGD). STUDY DESIGN: Quasi-experimental cross-over study. PLACE AND DURATION OF STUDY: Shifa College of Medicine, Islamabad, from March to December 2015. METHODOLOGY: All students of second year MBBS were assigned to either TBL or SGD, based on non-probability sampling, for 8 themes in a five-week module. The groups were flipped after 4 themes. TBL format recommended by the AMEE guide No: 65 was followed. The impact of both learning methods was assessed by comparing end-of-module written examination scores of the two groups through independent sample t-test. SPSS version 23 was used for data analysis. A p-value of <0.05 was considered statistically significant. RESULTS: End-of-module written examination scores showed there was no significant difference in student academic performance when they studied with TBL or SGD in themes 1-4 (TBL 61.90 ±13.01 versus SGD 59.65 ±11.56, p=0.41). However, for themes 5-8 there was a significant difference in scores (TBL 65.36 ±11.62 versus SGD 59.92 ±10.65, p=0.03) A trend towards higher scores was observed in content learned with TBL in all eight themes. CONCLUSION: TBL is equally effective as an instructional method as SGD. However, it could not be established that it results in significant improvement in learning.


Assuntos
Desempenho Acadêmico , Educação de Graduação em Medicina , Aprendizagem Baseada em Problemas , Estudos Cross-Over , Feminino , Processos Grupais , Humanos , Masculino , Paquistão
20.
Environ Sci Pollut Res Int ; 26(12): 12446-12458, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30847809

RESUMO

Cr(VI) tolerance level of phytopathogenic fungus viz., Macrophomina phaseolina (Tassi) Goid was assessed through growth, morphological, physiological, and metal accumulation assays. Initially, the fungus growth assays indicated that the fungus can grow over concentration range of 20-3000 ppm and exhibited high tolerance index (0.88-1.00) and minimum inhibitory concentration at 3500 ppm of Cr. Observations under compound and scanning electron microscope un-revealed the structural features of hyphae under Cr stress as thick-walled, aggregated, branched, short and broken, along with attachment of irregular objects on them. Metal accumulation analysis revealed reduction in Cr(VI) accumulation by the fungus with increase in metal concentration in the growth medium (500-3000 ppm). Cr stress induced upregulation of antioxidant enzyme activities (catalase, peroxidase and polyphenol oxidase), expression of genes (MSN1 and metallothionein) and appearnace of new protein bands suggesting the possible role in protection and survival of M. phaseolina against Cr(VI)-induced oxidative stress. This study concludes that interference of Cr with growth and physiological process of M. phaseolina could affect its infection level on its host plant, therefore, synergistic action of two factors needs to be addressed, which may aid to guide future research efforts in understanding impact of plant-pathogen-heavy metal interaction.


Assuntos
Ascomicetos/fisiologia , Cromo/toxicidade , Poluentes do Solo/toxicidade , Antioxidantes/metabolismo , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Expressão Gênica , Genes Fúngicos , Hifas
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