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1.
J Appl Psychol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38635204

RESUMO

We advance the trait approach to leadership by leveraging a large multinational database on leader emergence (k = 120 samples, N = 32,579) and leader effectiveness (k = 116, N = 42,487) to extend Judge et al.'s (2002) classic meta-analysis of Big Five personality and leadership. By testing novel hypotheses rooted in culturally endorsed implicit leadership theory and socioanalytic theory, we offer three unique insights. First, in collectivist societies (cultures that value interdependence with one's group), the five factor model traits-and leader Extraversion and Agreeableness in particular-are stronger predictors of leader effectiveness, consistent with the theorized need for enhanced social coordination in such cultures. Second, a theoretical model is proposed to specify that leader Big Five trait effects are mediated by leader behavior (confirming that Consideration mediates Extraversion and Agreeableness, whereas Initiating Structure mediates Conscientiousness, Extraversion, and Openness). Third, trait Honesty-Humility robustly predicts leader effectiveness beyond the Big Five traits, expanding the trait approach. New implications for understanding when and why personality traits predict leadership are discussed. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

2.
J Pharm Bioallied Sci ; 16(Suppl 1): S46-S48, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38595500

RESUMO

Dental casting machine is an electrical device used to extrude molten materials to fabricate dental prostheses such as crowns, bridges, intracoronal and extracoronal restorations, and removable partial dentures. The casting process basically include melting and casting. Firstly, the solid material is heated in a crucible in temperature-controlled conditions to melt the material to its smelled form. The dental casting process is a complex one with multifaceted steps and equipment. Different types of casting machines are available to produce heat using different sources and techniques. It includes Arc melting, Open flame casting, and Electrical resistance. Arc melting involves the application of an electric or gas discharge on tungsten electrodes, causing the metal base to melt utilizing the heat produced by arcing. Open flame casting or induction melting employs water-cooled alternate current induction coils to induce heat. However, resistance heating uses electric current to melt precious metals.

3.
Foods ; 12(4)2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36832780

RESUMO

Mycotoxins are deleterious fungal secondary metabolites that contaminate food and feed, thereby creating concerns regarding food safety. Common fungal genera can easily proliferate in Indian tropical and sub-tropical conditions, and scientific attention is warranted to curb their growth. To address this, two nodal governmental agencies, namely the Agricultural and Processed Food Products Export Development Authority (APEDA) and the Food Safety and Standards Authority of India (FSSAI), have developed and implemented analytical methods and quality control procedures to monitor mycotoxin levels in a range of food matrices and assess risks to human health over the last two decades. However, comprehensive information on such advancements in mycotoxin testing and issues in implementing these regulations has been inadequately covered in the recent literature. The aim of this review is thus to uphold a systematic picture of the role played by the FSSAI and APEDA for mycotoxin control at the domestic level and for the promotion of international trade, along with certain challenges in dealing with mycotoxin monitoring. Additionally, it unfolds various regulatory concerns regarding mycotoxin mitigation in India. Overall, it provides valuable insights for the Indian farming community, food supply chain stakeholders and researchers about India's success story in arresting mycotoxins throughout the food supply chain.

4.
Compr Rev Food Sci Food Saf ; 22(1): 473-501, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478122

RESUMO

Plant-based proteins are gaining a lot of attention for their health benefits and are considered as an alternative to animal proteins for developing sustainable food systems. Against the backdrop, ensuring a healthy diet supplemented with good quality protein will be a massive responsibility of governments across the globe. Increasing the yield of food crops has its limitations, including low acceptance of genetically modified crops, land availability for cultivation, and the need for large quantities of agrochemicals. It necessitates the sensible use of existing resources and farm output to derive the proteins. On average, the protein content of plant leaves is similar to that of milk, which can be efficiently tapped for food applications across the globe. There has been limited research on utilizing plant leaf proteins for food product development over the years, which has not been fruitful. However, the current global food production scenario has pushed some leading economies to reconsider the scope of plant leaf proteins with dedicated efforts. It is evident from installing pilot-scale demonstration plants for protein extraction from agro-food residues to cater to the protein demand with product formulation. The present study thoroughly reviews the opportunities and challenges linked to the production of plant leaf proteins, including its nutritional aspects, extraction and purification strategies, anti-nutritional factors, functional and sensory properties in food product development, and finally, its impact on the environment. Practical Application: Plant leaf proteins are one of the sustainable and alternative source of proteins. It can be produced in most of the agroclimatic conditions without requiring much agricultural inputs. It's functional properties are unique and finds application in novel food product formulations.


Assuntos
Produtos Agrícolas , Proteínas de Plantas , Animais , Proteínas de Plantas/análise , Plantas Geneticamente Modificadas , Suplementos Nutricionais , Folhas de Planta/química
5.
Artigo em Inglês | MEDLINE | ID: mdl-36512547

RESUMO

For the simultaneous identification and quantification of five nitrofurans metabolites in farmed shrimp and fish, 3-amino-2-oxazolidinone (AOZ), 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ), 1-aminohydantoine (AHD), semicarbazide (SEM), and 3,5-dinitrosalicylic acid hydrazide (DNSH), an accurate, precise, and specific method was developed. The mixture of water and methanol (60/40; v/v) was found to be the final optimised solvent for injection. The analytical run duration was 7 min, and the mobile phase included 2 mM methanol and ammonium formate. The new reference point for action (RPA) of 0.50 µg kg-1 as per EC/1871/2019 was taken into consideration and evaluated for the performance characteristics as per the CIR (EC)/2021/808 criteria. Specificity, relative retention time (≤0.25%) relative ion ratio (≤40%), linearity (0.25 to 2.0 µg kg-1), trueness (between 82.8 and 118.1%), repeatability (RSDr ≤14%), within lab reproducibility (RSDwr ≤16.9%), CCα (0.32-0.36 µg kg-1), ruggedness and relative matrix effect (≤14.26%) achieved acceptable values.


Assuntos
Nitrofuranos , Espectrometria de Massas em Tandem , Animais , Crustáceos/química , Crustáceos/metabolismo , Peixes/metabolismo , Metanol , Nitrofuranos/química , Nitrofuranos/metabolismo , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos
8.
Ann Pediatr Cardiol ; 14(4): 554-556, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35527760

RESUMO

An 11-month-old girl was detected to have muscular ventricular septal defect with hyperkinetic pulmonary hypertension (PH) was urgently operated upon. On follow-up, her PH worsened, resulting in right ventricular dysfunction and was later detected to have absent portal vein.

9.
J Ayurveda Integr Med ; 11(4): 539-546, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31387787

RESUMO

Recent discussions on Ayurvedic research almost always end up with a note of discontent about its current methodology and demands for radically different versions. Reinforcement of "classical methods (of the glorious past)" is being envisaged as an alternative. If research is systematic enquiry to bring out truth, its core construct applies to formation of knowledge anywhere in the world, any time, may it be ancient or modern. As a part of debating on the necessity of an alternative, this article tries to check the comparability of 'classical method' (as available from Darsanas and Ayurveda) with 'contemporary method' through examining how much the two systems correspond in relation to the basic construct and terminology of research, under nine domains. The domains include most of the cardinal aspects of research process such as philosophical constructs, research paradigm, basic approaches on reasoning, definition and classification of research, research process based on nature of relationship, planning of interventional research, technical terminology, research reporting and research fallacies. More than sixty technical terms related to classical method are selected and explored for their conformity with contemporary language of research. Meaningful agreement was obtained which suggested that the two systems are comparable. Leaving a space for more systematic, methodical and extensive critical comparison, this review concluded on a suggestion that, one who proposes radical changes in research methodology, may consider the comparability of the two systems, and rethink on an extremist demand for a total reconstruction. Instead, the modus operandi of revising Ayurvedic research may emphasise on prioritizing its preferences and practices.

10.
Adv Exp Med Biol ; 1174: 265-290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31713202

RESUMO

Amyloids are highly organized cross ß-sheet protein nanofibrils that are associated with both diseases and functions. Thermodynamically amyloids are stable structures as they represent the lowest free energy state that proteins can attain. However, recent studies suggest that amyloid fibrils can be dissociated by a change in environmental parameters such as pH and ionic strength. This reversibility of amyloids can not only be associated with disease, but function as well. In disease-associated amyloids, fibrils can act as reservoirs of cytotoxic oligomers. Recently, in higher organisms such as mammals, hormones were found to be stored in amyloid-like state, where these were reported to act as a reservoir of functional monomers. These hormone amyloids can dissociate to monomers upon release from the secretory granules, and subsequently bind to their respective receptors and perform their functions. In this book chapter, we describe in detail how these protein nanofibrils represent the densest possible peptide packing and are suitable for long-term storage. Thus, mimicking the feature of amyloids to release functional monomers, it is possible to formulate amyloid-based peptide/protein drugs, which can be used for sustained release.


Assuntos
Peptídeos , Amiloide/química , Animais , Armazenamento de Medicamentos , Nanofibras/química , Hormônios Peptídicos/química , Peptídeos/química , Vesículas Secretórias/metabolismo
11.
Food Chem ; 260: 336-343, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29699677

RESUMO

An accurate, reliable and fast multi-residue, multi-class method using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed and validated for simultaneous determination and quantification of 24 pharmacologically active substances of three different classes (Quinolones including fluoroquinolones, sulphonamides and tetracyclines) in aquaculture shrimps. Sample preparation involves extraction with acetonitrile containing 0.1% formic acid and followed by clean up with n-hexane and 0.1% methanol in water by UPLC-MS/MS within 8 min. The method was validated according to European Commission Decision 2002/657. Acceptable values were obtained for linearity (5-200 µg kg-1), specificity, Limit of Quantification (5-10 µg kg-1), recovery (between 83 and 100%), repeatability (RSD < 9%), within lab reproducibility (RSD < 15%), reproducibility (RSD ≤ 22%), decision limit (105-116 µg kg-1) and detection capability (110-132 µg kg-1). The validated method was applied to aquaculture shrimp samples from India.


Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Frutos do Mar/análise , Espectrometria de Massas em Tandem/métodos , Acetonitrilas/química , Animais , Aquicultura , Decápodes/química , Fluoroquinolonas/análise , Índia , Limite de Detecção , Quinolonas/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Sulfonamidas/análise , Tetraciclinas/análise
12.
J AOAC Int ; 100(3): 598-602, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28300021

RESUMO

This study enables the selective determination of inorganic arsenic (iAs) with a low detection limit using an economical instrument [atomic absorption spectrometer with hydride generation (HG)] to meet the regulatory requirements as per European Commission (EC) and Codex guidelines. Dry rice samples (0.5 g) were diluted using 0.1 M HNO3-3% H2O2 and heated in a water bath (90 ± 2°C) for 60 min. Through this process, all the iAs is solubilized and oxidized to arsenate [As(V)]. The centrifuged extract was loaded onto a preconditioned and equilibrated strong anion-exchange SPE column (silica-based Strata SAX 500 mg/6 mL), followed by selective and sequential elution of As(V), enabling the selective quantification of iAs using atomic absorption spectrometry with HG. In-house validation showed a mean recovery of 94% and an LOQ of 0.025 mg/kg. The repeatability (HorRatr) and reproducibility (HorRatR) values were <2, meeting the performance criteria mandated by the EC. The combined standard measurement uncertainty by this method was less than the maximum standard measurement uncertainty; thus, the method can be considered for official control purposes. The method was applied for the determination of iAs in husked rice samples and has potential applications in other food commodities.


Assuntos
Arsênio/análise , Análise de Alimentos , Oryza/química , Extração em Fase Sólida , Espectrofotometria Atômica , Peróxido de Hidrogênio , Reprodutibilidade dos Testes , Incerteza
13.
Biochemistry ; 53(38): 5995-6010, 2014 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-25181279

RESUMO

Protein aggregation and amyloid formation are known to play a role both in diseases and in biological functions. Transcription factor p53 plays a major role in tumor suppression by maintaining genomic stability. Recent studies have suggested that amyloid formation of p53 could lead to its loss of physiological function as a tumor suppressor. Here, we investigated the intrinsic amyloidogenic nature of wild-type p53 using sequence analysis. We used bioinformatics and aggregation prediction algorithms to establish the evolutionarily conserved nature of aggregation-prone sequences in wild-type p53. Further, we analyzed the amyloid forming capacity of conserved and aggregation-prone p53-derived peptides PILTIITL and YFTLQI in vitro using various biophysical techniques, including all atom molecular dynamics simulation. Finally, we probed the seeding ability of the PILTIITL peptide on p53 aggregation in vitro and in cells. Our data demonstrate the intrinsic amyloid forming ability of a sequence stretch of the p53 DNA binding domain (DBD) and its aggregation templating behavior on full-length and p53 core domain. Therefore, p53 aggregation, instigated through an amyloidogenic segment in its DBD, could be a putative driving force for p53 aggregation in vivo.


Assuntos
Sequência Conservada , Proteína Supressora de Tumor p53/metabolismo , Sequência de Aminoácidos , Amiloide , DNA/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Agregados Proteicos , Agregação Patológica de Proteínas , Ligação Proteica , Estrutura Terciária de Proteína , Proteína Supressora de Tumor p53/química
14.
Langmuir ; 30(13): 3775-86, 2014 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-24678792

RESUMO

It has been suggested that conjugated charged polymers are amyloid imaging agents and promising therapeutic candidates for neurological disorders. However, very less is known about their efficacy in modulating the amyloid aggregation pathway. Here, we studied the modulation of Parkinson's disease associated α-synuclein (AS) amyloid assembly kinetics using conjugated polyfluorene polymers (PF, cationic; PFS, anionic). We also explored the complexation of these charged polymers with the various AS aggregated species including amyloid fibrils and oligomers using multidisciplinary biophysical techniques. Our data suggests that both polymers irrespective of their different charges in the side chains increase the fibrilization kinetics of AS and also remarkably change the morphology of the resultant amyloid fibrils. Both polymers were incorporated/aligned onto the AS amyloid fibrils as evident from electron microscopy (EM) and atomic force microscopy (AFM), and the resultant complexes were structurally distinct from their pristine form of both polymers and AS supported by FTIR study. Additionally, we observed that the mechanism of interactions between the polymers with different species of AS aggregates were markedly different.


Assuntos
Amiloide/química , Polímeros de Fluorcarboneto/química , Agregados Proteicos , alfa-Sinucleína/química , Sequência de Aminoácidos , Benzotiazóis , Escherichia coli/genética , Escherichia coli/metabolismo , Polímeros de Fluorcarboneto/síntese química , Expressão Gênica , Humanos , Cinética , Microscopia de Força Atômica , Dados de Sequência Molecular , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Tiazóis , alfa-Sinucleína/genética
15.
Biochemistry ; 53(5): 807-9, 2014 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-24450731

RESUMO

α-Synuclein (α-Syn) aggregation is directly implicated in both the initiation and spreading of Parkinson's Diseases (PD) pathogenesis. Although the familial PD-associated mutations (A53T, E46K, and A30P) are known to affect the aggregation kinetics of α-Syn in vitro, their structural differences in resultant fibrils are largely unknown. In this report we studied the site-specific dynamics of wild type (wt) α-Syn and its three PD mutant fibrils using time-resolved fluorescence intensity, anisotropy decay kinetics, and fluorescence quenching. Our data suggest that the N- and C-terminus are more flexible and exposed compared to the middle non-amyloid-ß component (NAC) region of wt and PD mutant α-Syn fibrils. Yet the N-terminus showed great conformational heterogeneity compared to the C-terminus for all these proteins. 71 position of E46K showed more flexibility and solvent exposure compared to other α-Syns, whereas both E46K and A53T fibrils possess a more rigid C-terminus compared to wt and A30P. The present data suggest that wt and PD mutant fibrils possess large differences in flexibility and solvent exposure at different positions, which may contribute to their different pathogenicity in PD.


Assuntos
Doença de Parkinson/genética , alfa-Sinucleína/genética , Anisotropia , Fluorescência , Humanos , Mutagênese Sítio-Dirigida , Mutação , Doença de Parkinson/metabolismo , Conformação Proteica , alfa-Sinucleína/química
16.
Biochemistry ; 52(49): 8800-10, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24236650

RESUMO

Glycosaminoglycans (GAGs) have been reported to play a significant role in amyloid formation of a wide range of proteins/peptides either associated with diseases or native biological functions. The exact mechanism by which GAGs influence amyloid formation is not clearly understood. Here, we studied two closely related peptides, glucagon-like peptide 1 (GLP1) and glucagon-like peptide 2 (GLP2), for their amyloid formation in the presence and absence of the representative GAG heparin using various biophysical and computational approaches. We show that the aggregation and amyloid formation by these peptides follow distinct mechanisms: GLP1 follows nucleation-dependent aggregation, whereas GLP2 forms amyloids without any significant lag time. Investigating the role of heparin, we also found that heparin interacts with GLP1, accelerates its aggregation, and gets incorporated within its amyloid fibrils. In contrast, heparin neither affects the aggregation kinetics of GLP2 nor gets embedded within its fibrils. Furthermore, we found that heparin preferentially influences the stability of the GLP1 fibrils over GLP2 fibrils. To understand the specific nature of the interaction of heparin with GLP1 and GLP2, we performed all-atom MD simulations. Our in silico results show that the basic-nonbasic-basic (B-X-B) motif of GLP1 (K28-G29-R30) facilitates the interaction between heparin and peptide monomers. However, the absence of such a motif in GLP2 could be the reason for a significantly lower strength of interaction between GLP2 and heparin. Our study not only helps to understand the role of heparin in inducing protein aggregation but also provides insight into the nature of heparin-protein interaction.


Assuntos
Amiloide/química , Peptídeo 1 Semelhante ao Glucagon/química , Peptídeo 2 Semelhante ao Glucagon/química , Heparina/química , Sequência de Aminoácidos , Amiloide/ultraestrutura , Naftalenossulfonato de Anilina/química , Corantes Fluorescentes/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Ligação Proteica , Multimerização Proteica , Estrutura Secundária de Proteína , Triptofano/química
17.
Biochemistry ; 52(40): 6925-7, 2013 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-24047453

RESUMO

α-Synuclein (α-Syn) aggregation is directly linked with Parkinson's disease (PD) pathogenesis. Here, we analyzed the aggregation of newly discovered α-Syn missense mutant H50Q in vitro and found that this mutation significantly accelerates the aggregation and amyloid formation of α-Syn. This mutation, however, did not alter the overall secondary structure as suggested by two-dimensional nuclear magnetic resonance and circular dichroism spectroscopy. The initial oligomerization study by cross-linking and chromatographic techniques suggested that this mutant oligomerizes to an extent similar to that of the wild-type α-Syn protein. Understanding the aggregation mechanism of this H50Q mutant may help to establish the aggregation and phenotypic relationship of this novel mutant in PD.


Assuntos
Doença de Parkinson/genética , Multimerização Proteica , alfa-Sinucleína/química , alfa-Sinucleína/genética , Amiloide/metabolismo , Humanos , Mutação de Sentido Incorreto , Doença de Parkinson/metabolismo , Estrutura Quaternária de Proteína
18.
Malays Orthop J ; 7(1): 19-24, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25722802

RESUMO

UNLABELLED: Reconstruction of degenerated ruptures of the tendoachilles is a challenge. Ruptured tendons and the remaining tendon ends are abnormal. A number of methods have been described in literature reconstruct the tendoachilles, but with variable results(1). We used peroneus brevis tendon in 20 patients to augment the repair of degenerated tendoachilles tears by creating a dynamic loop as described by Teuffer et al(2). All patients were followed up for atleast 18 months. At the last postoperative visit, 18 out of 20 patients were able to do a toe raise. Eighty-five per cent of patients had excellent or good results and 15% had fair or poor results using modified Rupp scoring. Advantages offered by this procedure are the use of a single incision and mini incision and use of a dispensable tendon such as the peroneus brevis without entirely depending on the damaged tendon for healing. KEY WORDS: Degenerative tear of tendoachilles, augmented repair, peroneus brevis tendon.

19.
J Food Sci Technol ; 49(5): 530-6, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24082263

RESUMO

With excellent quality and flavour of fresh fruits, young leaves of cactus serve as nutritious vegetable and salad dish and the immature fruits for making mock-gherkins. Cactus, with high water use efficiency produce forage for animals, vegetables, and fruits with 14% glucose. Traditionally cactus used as a valuable health supporting nutrient and it also has applications in pharmaceutical industries. Cactus with number of uses has immense potential to be the food of future.

20.
Nano Rev ; 22011.
Artigo em Inglês | MEDLINE | ID: mdl-22110868

RESUMO

Amyloid fibrils belong to the group of ordered nanostructures that are self-assembled from a wide range of polypeptides/proteins. Amyloids are highly rigid structures possessing a high mechanical strength. Although amyloids have been implicated in the pathogenesis of several human diseases, growing evidence indicates that amyloids may also perform native functions in host organisms. Discovery of such amyloids, referred to as functional amyloids, highlight their possible use in designing novel nanostructure materials. This review summarizes recent advances in the application of amyloids for the development of nanomaterials and prospective applications of such materials in nanotechnology and biomedicine.

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