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1.
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.

2.
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
3.
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
4.
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.

5.
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.

6.
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
7.
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
8.
Cureus ; 10(4): e2418, 2018 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-29888147

RESUMO

Objective The objective of our study was to determine whether cadaveric dissection is a necessity in medical education. Another purpose of our study was to assess the attitude and perception of consultants, residents, and fellows about cadaveric dissection and whether it helped them in their medical practices. Method We performed an analytical cross-sectional study among consultants, fellows, and residents of different specialty areas practicing in Punjab. A self-constructed questionnaire compromising of 41 items was used to assess the perception of doctors about cadaveric dissection and other alternative anatomy teaching methods. Consultants, fellows, and residents who were in clinical practice for more than six months were included in the study. Results Out of the total sample size of 842, 44.7% were female medical doctors and 55.3 % were male medical doctors. Cadaveric dissection was thought to be the most effective method for teaching anatomy by 27.9% of the doctors. Mean cadaveric dissection, prosection and didactic teaching components were scored significantly higher by doctors in surgery and allied fields (p<0.001). Doctors in the surgical and allied field were 0.55 times less likely to think that cadaveric dissection was unethical as compared to doctors working in medicine and allied fields (p<0.001). Conclusion Dissection is still considered by several doctors as a valuable source of learning anatomy. However, the future of teaching anatomy does not depend on any single method. It is, in fact, the right combination of all available resources and using them in an interactive way that maximizes outcomes.

9.
Braz. j. infect. dis ; 20(1): 41-47, Jan.-Feb. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-776468

RESUMO

Abstract Background Fluoroquinolones are the backbone of multidrug resistant tuberculosis treatment regimens. Despite the high burden of multidrug resistant tuberculosis in the country, little is known about drug resistance patterns, prevalence, and predictors of fluoroquinolones resistance among multidrug resistant tuberculosis patients from Pakistan. Objective To evaluate drug resistance patterns, prevalence, and predictors of fluoroquinolones resistance in multidrug resistant tuberculosis patients. Methods This was a cross-sectional study conducted at a programmatic management unit of drug resistant tuberculosis, Lady Reading Hospital Peshawar, Pakistan. Two hundred and forty-three newly diagnosed multidrug resistant tuberculosis patients consecutively enrolled for treatment at study site from January 1, 2012 to July 28, 2013 were included in the study. A standardized data collection form was used to collect patients’ socio-demographic, microbiological, and clinical data. SPSS 16 was used for data analysis. Results High degree of drug resistance (median 5 drugs, range 2–8) was observed. High proportion of patients was resistant to all five first-line anti-tuberculosis drugs (62.6%), and more than half were resistant to second line drugs (55.1%). The majority of the patients were ofloxacin resistant (52.7%). Upon multivariate analysis previous tuberculosis treatment at private (OR = 1.953, p = 0.034) and public private mix (OR = 2.824, p = 0.046) sectors were predictors of ofloxacin resistance. Conclusion The high degree of drug resistance observed, particularly to fluoroquinolones, is alarming. We recommend the adoption of more restrictive policies to control non-prescription sale of fluoroquinolones, its rational use by physicians, and training doctors in both private and public–private mix sectors to prevent further increase in fluoroquinolones resistant Mycobacterium tuberculosis strains.


Assuntos
Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Antituberculosos/farmacologia , Fluoroquinolonas/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Estudos Transversais , Testes de Sensibilidade Microbiana , Paquistão , Prevalência
10.
Respir Med ; 106 Suppl 2: S16-24, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23290700

RESUMO

Few recent comparative data exist on smoking habits in the Middle East and North Africa (MENA) region. The objective of this analysis was to evaluate smoking patterns in a large general population sample of individuals aged ≥ 40 years in ten countries in the region (Algeria, Egypt, Jordan, Lebanon, Morocco, Saudi Arabia, Syria, Tunisia, Turkey and United Arab Emirates), together with Pakistan, using a standardised methodology. A random sample of 457,258 telephone numbers was generated and called. This identified 65,154 eligible subjects, of whom 62,086 agreed to participate. A screening questionnaire was administered to each participant, which included six questions relating to cigarette consumption and waterpipe use. The age- and gender-adjusted proportion of respondents reporting current or past smoking of cigarettes or waterpipes was 31.2% [95% CI: 30.9-31.6%]. This proportion was significantly higher (p < 0.001) in men (48.0%) than in women (13.8%), but no relevant differences were observed between age groups. Smoking rates were in general lowest in the Maghreb countries and Pakistan and highest in the Eastern Mediterranean countries, ranging from 15.3% in Morocco to 53.9% in Lebanon. Consumption rates were 28.8% [28.4-29.2%] for cigarette smoking and 3.5% [3.4-3.6%] for waterpipe use. Use of waterpipes was most frequent in Saudi Arabia (8.5% of respondents) but remained low in the Maghreb countries (< 1.5%). Cumulative cigarette exposure was high, with a mean number of pack · years smoked of 18.5 ± 20.5 for women and 29.1 ± 26.2 for men. In conclusion, smoking is a major health issue in the MENA region.


Assuntos
Fumar/epidemiologia , Adulto , África do Norte/epidemiologia , Distribuição por Idade , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oriente Médio/epidemiologia , Paquistão/epidemiologia , Distribuição por Sexo
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