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1.
Nanotechnology ; 32(19): 195208, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33503597

RESUMO

Highly luminescent all-inorganic cesium lead bromide (CsPbBr3) perovskite quantum dots (QDs) have been extensively used as a photosensitizer in optoelectronic devices, while p-type small-organic-molecule copper phthalocyanine (CuPc) is also widely used as a photoactive material in solar cells, organic field-effect transistors (OFETs), etc. In this paper, we report the preparation of a CsPbBr3-QDs/CuPc heterostructure to study the effect of CsPbBr3-QDs on CuPc. The optical properties of both CuPc and the QDs/CuPc heterostructure were compared and contrasted using UV-vis absorbance and photoluminescence (PL) measurements. Furthermore, to study their electronic and charge transfer features, we fabricated field-effect transistors (FETs) on both pristine CuPc and QDs/CuPc heterostructure thin films and studied their photoresponsive electrical characteristics. Both pristine and QDs/CuPc-based FETs showed an enhancement in current and carrier mobility under illumination. The enhancement in the current and carrier mobility of the QDs/CuPc-based FETs is due to a large number of photoexcited charge carriers. We also observed that the current and carrier mobility in the QDs/CuPc heterostructure-based FET were lower than those of the pristine CuPc-based FET. This can be explained by the n-type doping effect of CsPbBr3 QDs on CuPc, which reduces the accumulation of holes in the active p-channel near the insulating layer and causes charge to be transferred from the QDs to the CuPc. Thus, we have observed a charge transfer effect in the CsPbBr3 QDs/CuPc heterostructure, which can be used in optoelectronic devices.

2.
AAPS PharmSciTech ; 22(6): 216, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34386888

RESUMO

5-Fluorouracil (5-FU) is the most preferred chemotherapeutic agent in the management of colon cancer but is associated with poor therapeutic efficacy and lack of site specificity. Hence, it was aimed to employ Eudragit S100 surface engineered 5-FU nanostructured lipid carriers for the spatial and temporal release of the drug for the treatment of colon cancer. Hot high-pressure homogenization (HPH) technique was employed in the preparation of 5-FU-NLCs. The optimization of 5-FU-NLCs was performed using a Quality by Design (QbD) approach. A 32 factorial design was employed wherein the relationship between independent variables [amount of oleic acid (X1) and concentration of Tween®80 (X2)] and dependent variables [particle size (Y1) and % entrapment efficiency (Y2)] was studied. Optimized 5-FU-NLCs were surface treated to obtain Eudragit S100-coated 5-FU-NLCs (EU-5-FU-NLCs). The evaluation parameters for 5-FU-NLCs and EU-5-FU-NLCs included surface morphology, particle size, PDI, and zeta potential. In vitro release from EU-5-FU-NLCs revealed a selective and controlled 5-FU release in the colonic region for 24 h. In vitro cytotoxicity (MTT assay) was performed against Caco-2 cancer cells, wherein EU-5-FU-NLCs exhibited a 2-fold greater cytotoxic potential in comparison to a 5-FU solution (5-FU-DS). Oral administration of EU-5-FU-NLCs in Albino Wistar rats depicted a higher Cmax (2.54 folds) and AUC (11 folds) as well as prolonged Tmax (16 folds) and MRT (4.32 folds) compared to 5-FU-DS confirming higher bioavailability along with the spatial and temporal release in the colonic region. Thus, a multifaceted strategy involving abridgement of nanotechnology along with surface engineering is introduced for effective chemotherapy of colon cancer via oral administration of 5-FU with uncompromised safety and higher efficacy.Graphical abstract.


Assuntos
Neoplasias do Colo , Portadores de Fármacos , Nanoestruturas , Ácidos Polimetacrílicos , Animais , Células CACO-2 , Colo , Neoplasias do Colo/tratamento farmacológico , Fluoruracila , Humanos , Lipídeos , Tamanho da Partícula , Ratos
3.
J Org Chem ; 85(8): 5312-5320, 2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32227865

RESUMO

In this work, 1,4-dioxane-mediated hydroxylhydrative aza-cyclization of 2-alkynylbenzamide is developed for the synthesis of 3-hydroxylisoindolin-1-ones. The transformation proceeds smoothly in water with good yields and a broad reaction scope. Mechanistic studies show that regioselective brimonative 5-exo-dig aza-cyclization, bromohydration of the resulting alkene groups, and hydrolysis of dibromo compounds are involved. Compared to the traditional methodologies, the synthetic procedure reported herein represents a cleaner route toward 3-hydroxylisoindolin-1-ones.

4.
Nanotechnology ; 30(29): 295501, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-30939462

RESUMO

Molybdenum disulfide (MoS2) quantum dots (QDs) are successfully synthesized by facile synthesis using ultrasonication assisted liquid exfoliation technique. The high and low boiling point solvents: N-methyl-pyrrolidone (NMP) and ethanol-water solution have been used for synthesis of MoS2 QDs. Similar size distribution of MoS2 QDs synthesized in two different solvents have been observed from the transmission electron microscopy and average size of these QDs are ∼5 nm. The film of MoS2 QDs is used to fabricate humidity sensor. The large edge to volume ratio and high surface active sites of QDs enhanced the water adsorption even at low humidity environment (<37% RH). The humidity sensing analysis shows that sensing film of MoS2 QDs synthesized in ethanol-water has an average sensitivity of 2.78 MΩ/%RH with fast response time (11 s), good repeatability and high stability. In view of these results, the work is highly applicable to fabricate high performance MoS2 QDs humidity sensor.

5.
Bioorg Chem ; 84: 24-31, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30476650

RESUMO

Analkali tolerant α-l-rhamnosidase has been purified to homogeneity from the culture filtrate of a new fungal strain, Fusarium moniliforme MTCC-2088, using concentration by ultrafiltration and cation exchange chromatography on CM cellulose column. The molecular mass of the purified enzyme has been found to be 36.0 kDa using SDS-PAGE analysis. The Km value using p-nitrophenyl-α-l-rhamnopyranoside as the variable substrate in 0.2 M sodium phosphate buffer pH10.5 at50 °C was 0.50 mM. The catalytic rate constant was15.6 s-1giving the values of kcat/Km is 3.12 × 104M-1 s-1. The pH and temperature optima of the enzyme were 10.5 and 50 °C, respectively. The purified enzyme had better stability at 10 °C in basic pH medium. The enzyme derhamnosylated natural glycosides like naringin to prunin, rutin to isoquercitrin and hesperidin to hesperetin glucoside. The purified α-l-rhamnosidase has potential for enhancement of wine aroma.


Assuntos
Produtos Biológicos/metabolismo , Fusarium/enzimologia , Glucosídeos/metabolismo , Glicosídeo Hidrolases/metabolismo , Biocatálise , Produtos Biológicos/química , Glucosídeos/química , Glicosídeo Hidrolases/isolamento & purificação , Concentração de Íons de Hidrogênio , Estrutura Molecular , Temperatura
6.
Drug Dev Ind Pharm ; 44(7): 1212-1221, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29429364

RESUMO

OBJECTIVE: Aim of the present study was to prepare curcumin (CUR) loaded biodegradable crosslinked gelatin (GE) film to alleviate the existing shortcomings in the treatment of periodontitis. SIGNIFICANCE: Gelatin film was optimized to provide anticipated mucoadhesive strength, mechanical properties, folding endurance, and prolonged drug release over treatment duration, for successful application in the periodontitis. METHODS: The film was developed by using solvent casting technique and "Design of Experiments" approach was employed for evaluating the influence of independent variables on dependent response variables. Solid-state characterization of the film was performed by FTIR, XRD, and SEM. Further, prepared formulations were evaluated for drug content uniformity, surface pH, folding endurance, swelling index, mechanical strength, mucoadhesive strength, in vitro biodegradation, and in vitro drug release behavior. RESULTS: Solid state characterization of the formulation showed that CUR is physico-chemically compatible with other excipients and CUR was entrapped in an amorphous form inside the smooth and uniform film. The optimized film showed degree of crosslinking 51.04 ± 2.4, swelling index 138.10 ± 1.25, and folding endurance 270 ± 3 with surface pH around 7.0. Crosslinker concentrations positively affected swelling index and biodegradation of film due to altered matrix density of the polymer. Results of in vitro drug release demonstrated the capability of the developed film for efficiently delivering CUR in a sustained manner up to 7 days. CONCLUSIONS: The developed optimized film could be considered as a promising delivery strategy to administer medicament locally into the periodontal pockets for the safe and efficient management of periodontitis.


Assuntos
Curcumina/química , Gelatina/química , Plásticos Biodegradáveis/química , Química Farmacêutica/métodos , Curcumina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos/efeitos dos fármacos , Excipientes/química , Humanos , Periodontite/tratamento farmacológico , Polímeros/química
7.
Bioorg Chem ; 70: 222-228, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28110962

RESUMO

An α-l-rhamnosidase secreting fungal strain has been isolated from the decaying goose berry (Emblica officinalis) fruit peel. The fungal strain has been identified as Penicillium greoroseum MTCC-9224. The α-l-rhamnosidase of this fungal strain has been purified to homogeneity using a simple procedure involving concentration by ultra filtration and an anion exchange chromatography on DEAE-cellulose. The purified enzyme gave a single protein band corresponding to molecular mass of 97kDa in SDS-PAGE analysis. The native-PAGE analysis also gave a single protein band confirming the purity of the enzyme. Using p-nitrophenyl-α-l-rhamnopyranoside as the substrate, Km and kcat values of the enzyme were 0.65mM and 43.65s-1, respectively. The pH and temperature optima of the enzyme were 6.5 and 57°C, respectively. The activation energy for the thermal denaturation of the enzyme was 27.9kJ/mol. The purified α-l-rhamnosidase hydrolyzed rutin to isoquercitrin and l-rhamnose but has no effect on naringin and hesperidin.


Assuntos
Glicosídeo Hidrolases/metabolismo , Penicillium/enzimologia , Quercetina/análogos & derivados , Rutina/metabolismo , Frutas/microbiologia , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Penicillium/química , Penicillium/isolamento & purificação , Penicillium/metabolismo , Phyllanthus emblica/microbiologia , Desnaturação Proteica , Quercetina/metabolismo , Especificidade por Substrato , Temperatura , Termodinâmica
8.
Drug Dev Ind Pharm ; 43(11): 1801-1816, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28673095

RESUMO

OBJECTIVE: Application of Plackett-Burman factorial design to investigate the effect of processing factors in the fabrication of ionically crosslinked chitosan-tripolyphosphate (CS-TPP) microspheres. SIGNIFICANCE: Microspheres were screened and optimized to provide maximum process yield (PY), encapsulation efficiency (EE), and time for 80% drug release (T80%) and minimum burst and particles size (PS), for successful application in periodontitis. METHODS: Processing factors viz. method of preparation (MOP), CS, TPP, crosslinking time (CT), agitation (AS), and drying technique (DT) were selected. Solid state characterization was performed by Fourier-Transform infrared (FTIR), differential scanning calorimetry (DSC), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Mucoadhesion, cytocompatibility, and stability of microspheres were also evaluated. RESULTS: Pareto analysis and analysis of variance, screened most significantly (p < .05) impacting process factors on selected responses. The optimized microspheres demonstrated: o/w emulsification method, CS (2.5%), TPP (5%), CT (120 min), AS (2000 rpm), and DT (freeze-dried), and provided PY- 95.67%, PS- 168.45%, EEOZ- 85.56%, EEDX- 91.34%, BOZ- 15.26%, BDX- 12.91%, TOZ- 47.09 and TDX- 67.95 minutes. FTIR illustrated compatibility between excipients and complexation of CS and TPP. XRD and DSC showed loss of crystallinity of entrapped drugs in microspheres. Biphasic drug release was observed for four days with non-Fickian kinetics. Furthermore, microspheres exhibited good mucoadhesivity (82.51%), antimicrobial activity against Staphylococcus aureus and Escherichia coli, cytocompatibility for L929 cells, and long-term stability. CONCLUSIONS: Therefore, CS-TPP microspheres were found mucoadhesive, safe, stable and provided controlled and prolonged release of drugs. These properties confirmed its high potential and applicability in chronic periodontitis.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Quitosana/análogos & derivados , Quitosana/química , Quitosana/farmacologia , Preparações de Ação Retardada/farmacologia , Microscopia Eletrônica de Varredura/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Staphylococcus aureus/química , Preparações de Ação Retardada/química , Microesferas , Tamanho da Partícula , Difração de Raios X
9.
Indian J Chest Dis Allied Sci ; 58(1): 59-61, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28394099

RESUMO

A 60-year-old female who was known to have rheumatoid arthritis for the preceding two-and-half years presented with difficulty in breathing associated with chest pain over the right hemithorax of two months duration. She was found to have a right-sided mild to moderate pleural effusion; there was no evidence of pleural thickening. The pleural fluid was pale yellow in appearance and diagnostic work-up confirmed it to be a pseudochylous pleural effusion. The present case highlights the rare occurrence of pseudochylothorax without pleural thickening as a complication of rheumatoid arthritis.


Assuntos
Artrite Reumatoide/complicações , Quilotórax/diagnóstico , Derrame Pleural/complicações , Derrame Pleural/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Pleura/diagnóstico por imagem , Toracentese , Tomografia Computadorizada por Raios X
10.
AAPS PharmSciTech ; 17(6): 1312-1325, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26689408

RESUMO

Metronidazole (MZ) and levofloxacin (LF) are widely employed for treatment of periodontitis, but high oral dose and resistance development after long-term oral administration limit their use. The aim of this study was to alleviate shortcomings in the treatment of periodontitis by fabrication of intrapocket, biodegradable films of chitosan (CS) loaded with MZ and LF meant for inserting into periodontal pockets to treat infections. The films were developed by solvent casting technique using propylene glycol as plasticizer and glutaraldehyde as crosslinking agent. Their physical characteristics, such as drug content, surface pH, swelling index, and folding endurance, exhibited results within limit. Further, FTIR and DSC studies revealed stability of films and compatibility between drugs and excipients. SEM images of films showed the presence of free drug particles on the surface causing burst effect. In vitro release in McIlvaine buffer pH 6.6 was of sustained nature assisted by the burst effect. CS and crosslinking agent concentrations negatively affected drug release and positively affected T90 (time for releasing 90% of the drug) due to altered matrix density. In contrast, the plasticizer concentration increases membrane permeability and hence increased drug release, lowering T90. Crosslinked films demonstrated sustained release up to 7 days. The antibacterial efficacy of films was tested on Staphylococcus aureus and Escherichia coli, indicating good antibacterial activity. Clinical trials on patients proved the therapeutic efficacy of the films by a significant (p < 0.05) decrease in the clinical markers of periodontitis, i.e. gingival index, plaque index and pocket depth. Conclusively, the films of MZ and LF were successful tools for the management of periodontitis.


Assuntos
Quitosana/química , Levofloxacino/química , Levofloxacino/uso terapêutico , Metronidazol/química , Metronidazol/uso terapêutico , Periodontite/tratamento farmacológico , Adulto , Antibacterianos/química , Antibacterianos/uso terapêutico , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Excipientes/química , Glutaral/química , Humanos , Pessoa de Meia-Idade , Bolsa Periodontal/microbiologia , Plastificantes/química , Método Simples-Cego , Staphylococcus aureus/efeitos dos fármacos , Adulto Jovem
11.
Environ Sci Pollut Res Int ; 31(14): 21302-21325, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38383933

RESUMO

The growing need to examine the adsorption capabilities of innovative materials in real-world water samples has encouraged a shift from single to multicomponent adsorption systems. In this study, a novel composite, PANI-g-SM was synthesized by covalently grafting a lignocellulosic biomass, Saccharum munja (SM) with polyaniline (PANI). The as-synthesized composite was investigated for the simultaneous adsorption of cationic (Methylene Blue (MB); Crystal Violet (CV)) and anionic dyes (Reactive Red 35 (RR); Fast Green FCF (FG)) from four single components and two binary systems, MB + RR and CV + FG. Further, the effect and interaction of pH (2-11), dosage (0.01-0.04 g/10 mL), and initial concentration (0.0313 to 0.1563 mmol/L) on the elimination of dyes by PANI-g-SM were studied through a novel design of Box-Behnken of Response Surface Methodology (RSM) technique which was found to be highly useful for revealing the chemistry of interfaces in multi-component systems. The extended Langmuir model for the binary system indicated the presence of synergism, as result the maximum monolayer adsorption capacity increased by 44.44%, 645.83%, 67.88%, and 441.07% for MB, RR, CV, and FG dye, respectively. Further, the adsorption process mainly followed a pseudo-second-order kinetic model, and the thermodynamic studies revealed the exothermic nature of adsorption for RR and FG dye while endothermic for MB and CV dye, respectively with Δ G varying from - 1.68 to - 6.12 kJ/mol indicating the spontaneity of the process. Importantly, the efficacy of the composite was evaluated for the treatment of textile industry effluent highlighting its potential as an adsorbent for wastewater treatment.

12.
Microbiol Resour Announc ; 13(3): e0088923, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38376342

RESUMO

We report here the genome sequence of a bubaline herpesvirus 1 isolated from Indian water buffalo. The bubaline herpesvirus 1 strain S102_1 was isolated in 2021 from a Murrah buffalo heifer with clinical presentation of pustular vulvovaginitis.

13.
Plasmonics ; 18(3): 955-969, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37229148

RESUMO

The major challenge in today's world is that medical research is facing the existence of a vast number of viruses and their mutations, which from time to time cause outbreaks. Also, the continuous and spontaneous mutations occurring in the viruses and the emergence of resistant virus strains have become serious medical hazards. So, in view of the growing number of diseases, like the recent COVID-19 pandemic that has caused the deaths of millions of people, there is a need to improve rapid and sensitive diagnostic strategies to initiate timely treatment for such conditions. In the cases like COVID-19, where a real cure due to erratic and ambiguous signs is not available, early intervention can be life-saving. In the biomedical and pharmaceutical industries, nanotechnology has evolved exponentially and can overcome multiple obstacles in the treatment and diagnosis of diseases. Nanotechnology has developed exponentially in the biomedical and pharmaceutical fields and can overcome numerous challenges in the treatment and diagnosis of diseases. At the nano stage, the molecular properties of materials such as gold, silver, carbon, silica, and polymers get altered and can be used for the creation of reliable and accurate diagnostic techniques. This review provides insight into numerous diagnostic approaches focused on nanoparticles that could have been established for quick and early detection of such diseases.

14.
Diagnostics (Basel) ; 13(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37296806

RESUMO

BACKGROUND AND MOTIVATION: Lung computed tomography (CT) techniques are high-resolution and are well adopted in the intensive care unit (ICU) for COVID-19 disease control classification. Most artificial intelligence (AI) systems do not undergo generalization and are typically overfitted. Such trained AI systems are not practical for clinical settings and therefore do not give accurate results when executed on unseen data sets. We hypothesize that ensemble deep learning (EDL) is superior to deep transfer learning (TL) in both non-augmented and augmented frameworks. METHODOLOGY: The system consists of a cascade of quality control, ResNet-UNet-based hybrid deep learning for lung segmentation, and seven models using TL-based classification followed by five types of EDL's. To prove our hypothesis, five different kinds of data combinations (DC) were designed using a combination of two multicenter cohorts-Croatia (80 COVID) and Italy (72 COVID and 30 controls)-leading to 12,000 CT slices. As part of generalization, the system was tested on unseen data and statistically tested for reliability/stability. RESULTS: Using the K5 (80:20) cross-validation protocol on the balanced and augmented dataset, the five DC datasets improved TL mean accuracy by 3.32%, 6.56%, 12.96%, 47.1%, and 2.78%, respectively. The five EDL systems showed improvements in accuracy of 2.12%, 5.78%, 6.72%, 32.05%, and 2.40%, thus validating our hypothesis. All statistical tests proved positive for reliability and stability. CONCLUSION: EDL showed superior performance to TL systems for both (a) unbalanced and unaugmented and (b) balanced and augmented datasets for both (i) seen and (ii) unseen paradigms, validating both our hypotheses.

15.
AAPS PharmSciTech ; 13(4): 1031-44, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22893314

RESUMO

The present study was performed to investigate potential of Eudragit RLPO-based nanosuspension of glimepiride (Biopharmaceutical Classification System class II drug), for the improvement of its solubility and overall therapeutic efficacy, suitable for peroral administration. Nanoprecipitation method being simple and less sophisticated was optimized for the preparation of nanosuspension. Physicochemical characteristics of nanosuspension in terms of size, zeta potential, polydispersity index, entrapment efficiency (% EE) and in vitro drug release were found within their acceptable ranges. The size of the nanoparticles was most strongly affected by agitation time while % EE was more influenced by the drug/polymer ratio. Differential scanning calorimetry and X-ray diffraction studies provided evidence that enhancement in solubility of drug resulted due to change in crystallinity of drug within the formulation. Stability study revealed that nanosuspension was more stable at refrigerated condition with no significant changes in particle size distribution, % EE, and release characteristics for 3 months. In vivo studies were performed on nicotinamide-streptozotocin-induced diabetic rat models for pharmacokinetic and antihyperglycaemic activity. Nanosuspension increased maximum plasma concentration, area under the curve, and mean residence time values significantly as compared to aqueous suspension. Oral glucose tolerance test and antihyperglycaemic studies demonstrated plasma glucose levels were efficiently controlled in case of nanosuspension than glimepiride suspension. Briefly, sustained and prolonged activity of nanosuspensions could reduce dose frequency, decrease drug side effects, and improve patient compliance. Therefore, glimepiride nanosuspensions can be expected to gain considerable attention in the treatment of type 2 diabetes mellitus due to its improved therapeutic activity.


Assuntos
Hipoglicemiantes/administração & dosagem , Nanopartículas/química , Ácidos Polimetacrílicos/química , Compostos de Sulfonilureia/administração & dosagem , Água/química , Animais , Química Farmacêutica/métodos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Estabilidade de Medicamentos , Feminino , Teste de Tolerância a Glucose/métodos , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Masculino , Tamanho da Partícula , Polímeros/química , Ratos , Solubilidade , Compostos de Sulfonilureia/química , Compostos de Sulfonilureia/farmacocinética , Compostos de Sulfonilureia/farmacologia , Suspensões/química , Suspensões/farmacocinética , Suspensões/farmacologia
16.
Prikl Biokhim Mikrobiol ; 48(3): 328-33, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22834305

RESUMO

An alpha-L-rhamnosidase secreting fungal strain has been isolated and identified as Aspergillus clavato-nanicus MTCC-9611. The enzyme was purified to homogeneity from the culture filtrate of the fungus using concentration by ultrafiltration membrane and ion-exchange chromatography on CM-cellulose. The native PAGE analysis confirmed the homogeneity of the purified enzyme. The SDS-PAGE analysis of the purified enzyme revealed a single protein band corresponding to the molecular weight 82 kDa. The alpha-L-rhamnosidase activity of Aspergillus clavato-nanicus MTCC-9611 had optimum at pH 10.0 and 50 degrees C. The K(m) values of the enzyme were 0.65 mM and 0.95 mM using p-nitrophenyl alpha-L-rhamnopyranoside and naringin as a substrates respectively. The enzyme transforms naringin to prunin at pH 10.0 and further hydrolysis of prunin to naringenin does not occur under these reaction conditions that makes alpha-L-rhamnosidase activity of Aspergillus clavatonanicus MTCC-9611 promising enzyme to get prunin for pharmaceutical purposes.


Assuntos
Aspergillus/enzimologia , Flavanonas/química , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Temperatura Alta , Concentração de Íons de Hidrogênio , Especificidade por Substrato
17.
Int J Appl Basic Med Res ; 11(2): 120-124, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33912436

RESUMO

The severe acute respiratory syndrome (SARS)-coronavirus- 2 (CoV-2) outbreak in Wuhan, China has now spread to many countries across the world including the India with an increasing death toll. On March 11, 2020, the new clinical condition COVID-19 (Corona-Virus-Disease-19) was declared a pandemic by the World Health Organization (WHO). Owing to its infectivity, high risk of transmission, and limited handling of dead bodies, published data on the course of diseases has been limited. Most patients with COVID-19 have a mild disease course and remain as asymptomatic carrier; however, few patients of older age and with co-morbidites develop severe disease leading on to fatality. If due to COVID-19 infection death occurs, an autopsy is unlikely. However in unnatural deaths the legal duty impels the proper performance of a full autopsy, to find out the cause and manner of death. The detailed autopsy examination along with histo-pathological findings in the organs of asymptomatic patient of COVID-19 and its comparison with microscopic findings in Aluminium Phosphide poisoning are discussed below. This will summarizes the research status for COVID-19 deaths, which will be important for evaluation of cause of death, prevention, control and clinical strategies of COVID-19.

18.
Viruses ; 13(5)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067745

RESUMO

The number of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) cases is increasing in India. This study looks upon the geographic distribution of the virus clades and variants circulating in different parts of India between January and August 2020. The NPS/OPS from representative positive cases from different states and union territories in India were collected every month through the VRDLs in the country and analyzed using next-generation sequencing. Epidemiological analysis of the 689 SARS-CoV-2 clinical samples revealed GH and GR to be the predominant clades circulating in different states in India. The northern part of India largely reported the 'GH' clade, whereas the southern part reported the 'GR', with a few exceptions. These sequences also revealed the presence of single independent mutations-E484Q and N440K-from Maharashtra (first observed in March 2020) and Southern Indian States (first observed in May 2020), respectively. Furthermore, this study indicates that the SARS-CoV-2 variant (VOC, VUI, variant of high consequence and double mutant) was not observed during the early phase of virus transmission (January-August). This increased number of variations observed within a short timeframe across the globe suggests virus evolution, which can be a step towards enhanced host adaptation.


Assuntos
COVID-19/epidemiologia , Filogeografia/métodos , SARS-CoV-2/genética , Adulto , COVID-19/genética , Feminino , Genoma Viral/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Mutação/genética , Filogenia , SARS-CoV-2/patogenicidade
19.
Appl Plant Sci ; 8(4): e11335, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32351796

RESUMO

PREMISE: A portable, simple, yet efficient method was developed for the rapid extraction of xylem sap from the stems and petioles of tomato plants for diagnostic and quantification assays of the xylem-colonizing wilt bacterium Ralstonia solanacearum. METHODS AND RESULTS: Xylem saps were extracted from tomato stem sections using negative pressure generated from handheld needleless syringes. The samples were collected from plants grown under different soil moisture levels at four days after inoculation with the pathogen. Pipette tips were modified to serve as adapters for the stem sections. The quantification of the bacterial load in the extracted sap was performed by plating sap dilutions in Kelman's triphenyltetrazolium chloride (TTC) medium. Pathogen identity was further confirmed by performing a PCR using R. solanacearum-specific primers. CONCLUSIONS: Due to its simplicity, portability, and thoroughness of extraction from predetermined tissue sizes, the method can potentially facilitate high-throughput onsite sampling from a large number of samples in a short time, which cannot be achieved with other available techniques.

20.
Org Lett ; 22(15): 5931-5935, 2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32662274

RESUMO

In this work, a palladium-catalyzed [2 + 2 + 1] cyclization of internal alkynes with double isocyanides is described. This facile procedure is efficient for synthesizing various pyrrolo[3,2-c]quinolin-2-amines. The reaction worked well with a broad reaction scope. In the process, it is believed that sequential double isocyanide insertion, 6-exo-dig cyclization of alkyne, and addition of an imino group are involved.

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