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1.
Mol Neurobiol ; 59(9): 5902-5924, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35831555

RESUMO

Neural cell adhesion molecule, an integrated molecule of immunoglobulin protein superfamily involved in cell-cell adhesion, undergoes various structural modifications through numerous temporal-spatial regulations that generously alter their expressions on cell surfaces. These varied expression patterns are mostly envisioned in the morphogenesis and innervations of different human organs and systems. The considerable role of NCAM in neurite growth, brain development and etc. and its altered expression of NCAM in proliferating tumour cells and metastasis of various human melanomas clearly substantiate its appropriateness as a cell surface marker for diagnosis and potential target for several therapeutic moieties. This characteristic behaviour of NCAM is confined to its novel biochemistry, structural properties, signalling interactions and polysialylation. In particular, the characteristic expressions of NCAM are mainly attributed by its polysialylation, a post-translational modification that attaches polysialyl groups to the NCAM. The altered expression of NCAM on cell surface develops curiosity amidst pharmaceutical scientists, which drives them to understand its role of such expressions in various human melanomas and to elucidate the promising therapeutic strategies that are currently available to target NCAM appositely. Therefore, this review article is articulated with an insight on the altered expressions of NCAM, the clinical significances and the consequences of such atypical expression patterns in various human organs and systems.


Assuntos
Melanoma , Moléculas de Adesão de Célula Nervosa , Adesão Celular , Sistemas de Liberação de Medicamentos , Humanos , Moléculas de Adesão de Célula Nervosa/metabolismo , Processamento de Proteína Pós-Traducional
2.
Fish Shellfish Immunol ; 98: 477-487, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31945485

RESUMO

Effect of bio-augmentation of Bacillus spp in biofloc on growth, survival and immunity in Indian white shrimp Penaeus indicus was evaluated. Nine Bacillus strains were isolated and screened individually as well as in the form of a consortia. To maintain a C:N ratio of 12:1 a blend of carbohydrate sources was used. Bio-augmentation with bacterial consortium and Virgibacillus sp. produced improved growth and immunity. Shrimp survival ranged from 80 to 95% among treatments. Production was higher (35%) in the biofloc tanks with an average body weight (ABW) of 10.89 ± 1.2 g. On evaluating the immune responses, it was found that trypsin significantly (P < 0.05) enhanced Prophenoloxidase (PO) activity in Lysinibacillus, Bacillus cereus, Bacillus licheniformis and Bacillus subtilis bio-augmented groups. Laminarin induced PO activity was observed in groups supplemented with Oceanobacillus sp., Bacillus sp.and Bacillus megaterium. The lysozyme (LZ) activity was significantly (P < 0.05) higher in B. cereus and Microbial Consortia (MC), while other treatments were less effective. Total hemocyte count (THC) significantly (P < 0.05) increased in all treatment groups compared to the control. Hyaline hemocyte (HH) count was significantly (P < 0.05) higher in the control group (14.43%). Semi granular hemocytes (SGH) was higher in groups treated with Lysinibacillus, Bacillus sp., B. licheniformis and B. subtilis. The granular hemocyte (GH) count was significantly (P < 0.05) higher in Virgibacillus sp., B. cereus, B.megaterium and Oceanobacillus sp. The biofloc alone (BF), treated and augmented with B. megaterium significantly (P < 0.05) increased phagocytic activity. Highly significant phagocytic index (PI) was observed in bio-augmented groups, BF and MC. The relative expression levels of immune genes were found to be significantly up-regulated in shrimps grown in bio-augmented groups. Enhanced immunological parameters implies that bio-augmentation of biofloc with Bacillus spp. improved immunity in shrimps. Hence, bio-augmentation of probiotics in biofloc may be useful in improving culture conditions to produce P. indicus.


Assuntos
Aquicultura/métodos , Bactérias/classificação , Penaeidae/fisiologia , Criação de Animais Domésticos , Animais , Penaeidae/imunologia , Organismos Livres de Patógenos Específicos
3.
J Neurosci Methods ; 331: 108525, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31756396

RESUMO

With the increasing concern of neurological diseases, the improvised therapy for neurodegenerative disorders such as Alzheimer's disease is crucial. Yet, the efficacious delivery of drug across blood-brain barrier (BBB) remains a formidable challenge. BBB acts as a gate keeper to prevent the ingress of harmful foreign agents into the brain. It has built a great interest in designing BBB models to boost the field of neurotherapeutics. Recently, microfluidic systems are gaining ground in cell culture and bio-system analysis. It creates a new era of micro engineered laboratory onto a chip by combining the benefits of both in vitro and in vivo models. The high-fidelity microfluidic BBB-on-a-Chip possess the engineered physiological microenvironment for real time monitoring of barrier properties with human derived stem cells. These emerging models have intrinsic merits of regulating micro-scale fluid delivery and versatile fabrication. Moreover, the progress of 3D printing technology and versatility of stem cells assist in fabricating these robust and reproducible models. This review revolves around the various approaches of modelling microfluidic BBBs and emphasises on the limitations of existing models and technology. It contributes to the interdisciplinary engineering aspects of BBB research and its magnificent impact on drug development.


Assuntos
Barreira Hematoencefálica , Doenças Neurodegenerativas , Encéfalo , Humanos , Microfluídica , Impressão Tridimensional
4.
Sci Rep ; 8(1): 8665, 2018 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-29875466

RESUMO

Biogeochemistry of oxygen minimum zone (OMZ) sediments, which are characterized by high input of labile organic matter, have crucial bearings on the benthic biota, gas and metal fluxes across the sediment-water interface, and carbon-sulfur cycling. Here we couple pore-fluid chemistry and comprehensive microbial diversity data to reveal the sedimentary carbon-sulfur cycle across a water-depth transect covering the entire thickness of eastern Arabian Sea OMZ, off the west coast of India. Geochemical data show remarkable increase in average total organic carbon content and aerial sulfate reduction rate (JSO42-) in the sediments of the OMZ center coupled with shallowing of sulfate methane transition zone and hydrogen sulfide and ammonium build-up. Total bacterial diversity, including those of complex organic matter degraders, fermentative and exoelectrogenic bacteria, and sulfate-reducers (that utilize only simple carbon compounds) were also found to be highest in the same region. The above findings indicate that higher organic carbon sequestration from the water-columns (apparently due to lower benthic consumption, biodegradation and biotransformation) and greater bioavailability of simple organic carbon compounds (apparently produced by fermetative microflora of the sediments) are instrumental in intensifying the carbon-sulfur cycle in the sediments of the OMZ center.

5.
Sci Rep ; 8(1): 6038, 2018 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-29643439

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

6.
J Med Eng Technol ; 42(1): 1-8, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29251059

RESUMO

In this work, we have used a time-frequency domain analysis method called discrete wavelet transform (DWT) technique. This method stand out compared to other proposed methods because of its algorithmic elegance and accuracy. A wavelet is a mathematical function based on time-frequency analysis in signal processing. It is useful particularly because it allows a weak signal to be recovered from a noisy signal without much distortion. A wavelet analysis works by analysing the image and converting it to mathematical function which is decoded by the receiver. Furthermore, we have used Shannon entropy and approximate entropy (ApEn) for extracting the complexities associated with electroencephalographic (EEG) signals. The ApEn is a suitable feature to characterise the EEGs because its value drops suddenly due to excessive synchronous discharge of neurons in the brain during epileptic activity in this study. EEG signals are decomposed into six EEG sub-bands namely D1-D5 and A5 using DWT technique. Non-linear features such as ApEn and Shannon entropy are calculated from these sub-bands and support vector machine classifiers are used for classification purpose. This scheme is tested using EEG data recorded from five healthy subjects and five epileptic patients during the inter-ictal and ictal periods. The data are acquired from University of Bonn, Germany. The proposed method is evaluated through 15 classification problems, and obtained high classification accuracy of 100% for two cases and it indicates the good classifying performance of the proposed method.


Assuntos
Eletroencefalografia/métodos , Epilepsia/diagnóstico , Máquina de Vetores de Suporte , Análise de Ondaletas , Algoritmos , Entropia , Humanos
7.
J Med Eng Technol ; 42(1): 9-17, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29188743

RESUMO

Epileptic seizures are manifestations of epilepsy. Careful analysis of EEG records can provide valuable insight and improved understanding of the mechanism causing epileptic disorders. The detection of epileptic form discharges in EEG is an important component in the diagnosis of epilepsy. As EEG signals are non-stationary, the conventional frequency and time domain analysis does not provide better accuracy. So, in this work an attempt has been made to provide an overview of the determination of epilepsy by implementation of Hurst exponent (HE)-based discrete wavelet transform techniques for feature extraction from EEG data sets obtained during ictal and pre ictal stages of affected person and finally classifying EEG signals using SVM and KNN Classifiers. The The highest accuracy of 99% is obtained using SVM.


Assuntos
Eletroencefalografia/métodos , Epilepsia/diagnóstico , Análise de Ondaletas , Algoritmos , Humanos , Máquina de Vetores de Suporte
8.
Sci Rep ; 7(1): 14439, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29089526

RESUMO

The unique hydrographic setting of the Bay of Bengal (BoB) makes it an ideal tropical marine system to study the influence of regional and global forcings on productivity and [CO2aq] through the late quaternary. Enormous fresh water flux into the BoB and consequent salinity stratification significantly weaken the convective mixing and wind driven processes which are commonly responsible for transport of nutrients to the euphotic zone driving primary productivity. Here we present a high resolution organic carbon-CaCO3 MAR and δ13CTOC records for the last 300 ky from the BoB. The results show significant productivity variation at marine isotope sub-stages and millennial timescales. Colder sub-stages and stadials (Dansgard-Oeschger cycle) show a boost in productivity which may be attributed to thinning of low salinity cap, thereby facilitating efficient nutrient transport across the euphotic zone by the combination of wind driven processes (entrainment and upwelling), convective mixing and cold core eddies. The [CO2aq] was a net result of global pCO2 variation and regional processes. Our long term high-resolution data indicates a possibility of marked change in productivity/biogeochemistry of BOB in the future due to global warming, thus affecting the coastal economy.

9.
J Med Eng Technol ; 41(8): 670-680, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29117768

RESUMO

Electroencephalogram (EEG) signal-processing techniques are the prominent role in the detection and prediction of epileptic seizures. The detection of epileptic activity is cumbersome and needs a detailed analysis of the EEG data. Therefore, an efficient method for classifying EEG data is required. In this work, a constructive pattern recognition strategy for analysing EEG data as normal and epileptic seizure has been proposed. With this strategy, the signals were decomposed into frequency sub-bands using discrete wavelet transform (DWT). principal component analysis (PCA) and linear discriminant analysis (LDA) are applied to reduce the dimensionality of EEG data. These reduced features were used as input to Naïve Bayes and K-Nearest Neighbour Classifier to classify normal or epileptic seizure signal. The performance of classifier was evaluated in terms of accuracy, sensitivity and specificity. The experimental results show that PCA with Naïve Bayes classifier provides 98.6% accuracy and LDA with Naïve Bayes classifier attains improved result of 99.8% accuracy. Also, the result shows that PCA, LDA with K-NN achieves 98.5% and 100% accuracy. This evaluation is used to propose a reliable, practical epilepsy detection method to enhance the patient's care and quality of life.


Assuntos
Eletroencefalografia/métodos , Epilepsia/fisiopatologia , Algoritmos , Teorema de Bayes , Análise Discriminante , Humanos , Análise de Componente Principal , Qualidade de Vida , Análise de Ondaletas
10.
J Med Eng Technol ; 41(4): 288-297, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28277813

RESUMO

Continuous measurement of heart rate is necessary for monitoring the patients with heart ailments. A wearable which continuously measures heart rate of an individual by a method called reflectance-based photoplethysmography (PPG) computes the heart rate of an individual according to the volumetric changes in blood flowing through the body is developed. In order to make the device more compact as well as with IP67 and IP68 standard, wireless charging technique is employed because it helps to get rid of wires while charging. Following the Qi standard for designing wireless power receiver circuits makes the device interoperable and work with greater efficiency with reduced losses. Impedance matching and designing the circuit to operate under resonance condition increases coupling efficiency in case of inductive coupling.


Assuntos
Frequência Cardíaca/fisiologia , Tecnologia sem Fio , Humanos , Fotopletismografia
11.
Indian J Cancer ; 52(4): 580-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26960484

RESUMO

BACKGROUND: Plethora of information exists in the literature on pathology of the glioma while prevailing research data on quality-of-life (QOL) of glioma patients marks dearth thus demanding more studies. AIMS: In this study, we examined the QOL of different grades of glioma patients among the Chennai population in India. MATERIALS AND METHODS: A total of 162 patients with different grades of glioma enrolled from August 2007 to February 2011, at their first contact to Department of Neurology and Neurosurgery, Government General Hospital, Chennai, India were included and their QOL was assessed by European Organization for Research and Treatment of Cancer Core QOL questionnaire (EORTC QLQc-30), EORTC brain cancer module (QLQ BN-20). RESULTS AND CONCLUSION: Both low and high grade glioma (LGG and HGG) patients had poor mean scores in social functioning (87.0), physical functioning (82.0) and emotional functioning (75.2) and role functioning (58.9). The mean scores on cognitive functioning (61.9) and global QOL (60.3) were better. Age, Karnofsky performance status, World Health Organization grades showed significant associations with all functional scales. The percentage values were higher for symptoms of fatigue (76.9%), pain (71.5%), financial difficulties (77.6%) and appetite loss (38.46%) in both LGG and HGG. Similarly, with respect to QLQ-BN20 domains, HGG patients showed more symptoms than low grade with a significant correlation in communication deficit problems (P = 0.02), headache (P = 0.04), seizures (P < 0.01), hair loss (P < 0.05) than the other symptoms. This initial assessment suggests that an increasing burden of symptoms exists, with poor QOL and survival, which has become a major concern in different grades of glioma patients.


Assuntos
Neoplasias Encefálicas/psicologia , Glioma/psicologia , Qualidade de Vida , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/patologia , Feminino , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Resultado do Tratamento , Adulto Jovem
12.
Arch Virol ; 158(11): 2359-63, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23685897

RESUMO

Mumps is a vaccine-preventable disease that usually occurs as a self-limiting parotitis, but it can also lead to several life-threatening complications, including pancreatitis, meningitis, and encephalitis. The molecular epidemiology of the virus is poorly understood. The present study describes an outbreak of mumps virus infection in Punjab, India. The etiology was confirmed by serology and RNA detection to be mumps virus in 72 % of the cases and 50 % of contacts. This study, for the first time, revealed the mumps virus genotypes circulating in the Indian subcontinent as subtype G2 of genotype G.


Assuntos
Surtos de Doenças , Epidemiologia Molecular , Vírus da Caxumba/genética , Caxumba/epidemiologia , Caxumba/virologia , Anticorpos Antivirais/sangue , Criança , Feminino , Genótipo , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Índia/epidemiologia , Masculino , Tipagem Molecular , Vírus da Caxumba/classificação , Vírus da Caxumba/imunologia , Vírus da Caxumba/isolamento & purificação , Parotidite/epidemiologia , Parotidite/virologia , RNA Viral/sangue , RNA Viral/genética , RNA Viral/isolamento & purificação
13.
Langmuir ; 22(4): 1846-51, 2006 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-16460116

RESUMO

By the reaction of the appropriate organometallic precursors and tetrakishydroxymethyl phosphonium chloride (THPC) at the toluene-water interface, we have prepared nanocrystalline films of Au-Ag and Au-Cu alloys with a range of compositions. The films have been characterized by X-ray diffraction, electron microscopy, optical spectroscopy, and other techniques, besides compositional analysis. The particle size of the nanocrystals in the films varies with the composition. The surface plasmon band of the alloy films as well as of the organosols obtained by the disintegration of the films by the addition of an alkanethiol show the expected composition dependence. It has been possible to prepare the nanocrystalline films of a ternary Au-Ag-Cu alloy.

14.
J Hosp Infect ; 52(3): 181-4, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12419270

RESUMO

Methicillin-resistant Staphylococcus aureus (MRSA) is an important hospital-acquired pathogen in healthcare centres worldwide. The strain characteristics vary widely from country to country, although some strains have the propensity to spread globally. E-MRSA 15 and 16 have been established as epidemic strains in the UK and Europe. MRSA is widely prevalent in the Indian sub-continent and is endemic in the Burns Unit of St Johns Medical College Hospital, Bangalore, India. The purpose of the study was to investigate the predominance of one or more epidemic strains within an endemic situation. A representative selection of 65 isolates of MRSA over a period spanning five years (1994-1998) was subjected to antibiogram comparison, phage-typing and pulsed field gel electrophoresis (PFGE) using SmaI. The antibiogram comparison was not a discerning method of strain discrimination. At least 11 different phage-types were seen among these 65 isolates; 35.4% belonged to phage-types A and SM-A. PFGE studies showed 12 distinct patterns, with a single pattern accounting for over half of the isolates. The study showed that the isolates from India were diverse and distinct from strains of MRSA such as E-MRSA reported from many studies in the UK. Molecular characterization of isolates is a source of valuable information that could enhance global surveillance; more work is needed across the Indian sub-continent to establish the nature of MRSA strain diversity.


Assuntos
Unidades de Queimados , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Doenças Endêmicas/estatística & dados numéricos , Resistência a Meticilina/genética , Filogenia , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/genética , Tipagem de Bacteriófagos , Impressões Digitais de DNA , DNA Bacteriano/análise , DNA Bacteriano/genética , Eletroforese em Gel de Campo Pulsado , Humanos , Índia/epidemiologia , Controle de Infecções , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Vigilância da População , Sorotipagem
16.
Life Sci ; 58(13): 1039-45, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8622556

RESUMO

Pharmacological action of enkephalins as opioid peptides is limited because of their rapid degradation by endoproteases. A novel approach is used in this study to prolong the life of those peptides. Phosphorylation of N-terminal tyrosine residue is found to have a profound influence in improving the stability of [Met]enkephalin and [Leu]enkephalin against the action of aminopeptidase M. Whereas, breakdown of [Met]enkephalin and [Leu]enkephalin is essentially complete in less than one min when incubated at 37 degree C with purified aminopeptidase M (EC3.4.11.2; substrate:enzyme = 1:0.1) in Tris buffer (pH 7.02), the corresponding phospho analogs are still detected 60 min after start of incubation. The rate of disappearance of phospho-[Met]enkephalin and phospho-[Leu]enkephalin follows first-order kinetics with half-lives of 7.3 and 8.3 min, respectively.


Assuntos
Aminopeptidases/metabolismo , Encefalinas/metabolismo , Sequência de Aminoácidos , Animais , Cromatografia Líquida de Alta Pressão , Encefalina Leucina/metabolismo , Encefalina Metionina/metabolismo , Encefalinas/química , Rim/enzimologia , Cinética , Metionil Aminopeptidases , Microssomos/enzimologia , Dados de Sequência Molecular , Fosforilação , Especificidade por Substrato , Suínos
17.
Rapid Commun Mass Spectrom ; 9(12): 1148-54, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7579627

RESUMO

Liquid secondary ionization mass spectrometry (LSIMS) operating in the positive- and negative-ion modes was used to study fragmentation profiles and to obtain the amino acid sequences of a set of seven phosphoenkephalin peptides. The use of glycerol as the liquid matrix led to increase in fragmentation of phosphopeptides. The prominent amino acid sequence-determining ions in the positive-ion mode are y-type C-terminal ions; the N-terminal sequence-specific ions are observed sporadically. The most dominant ions in those mass spectra, however, are the immonium ions and a few low-mass side-chain cleavage products. The mass spectra in the negative-ion mode are more information-rich, and provide data complementary to that from the positive-ion mode. The phosphate group marker ions, m/z 79 (PO-3) and 97 (H2PO-4), are prominent and both N- and C-termini sequence ions are formed with equal facility in this mode of analysis. Both positive- and negative-ion mass spectral data are useful in determining the amino acid sequence of all the seven phosphoenkephalins. Thus, LSIMS alone can be a viable option to the tandem mass spectrometry approach when sufficient quantities (> 50 nmol) of phosphopeptides are available.


Assuntos
Encefalinas/química , Fosfopeptídeos/química , Sequência de Aminoácidos , Dados de Sequência Molecular , Espectrometria de Massa de Íon Secundário
18.
J Chromatogr A ; 678(2): 249-57, 1994 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-7951986

RESUMO

The use of reversed-phase high-performance liquid chromatography for the separation of a mixture of 14 phosphorylated and non-phosphorylated enkephalins is described. The influence of two homologous series of hydrophobic ion-pairing reagents, consisting of perfluorinated carboxylic (trifluoroacetic, pentafluoropropionic and hexafluorobutyric) acids and sodium salts of sulfonic (butane-, hexane- and heptane-) acids, on the retention of enkephalin peptides was investigated. The incorporation of the phosphate group reduces retention time in proportion with the resulting change in hydrophobicity of the peptide. All peptides exhibit increase in retention time with increase in the counter ion hydrophobicity. The increase is proportional to the number of positively charged groups present in a peptide. Phosphopeptides show small increases in retention times than their corresponding non-phospho derivatives. The near-neighbor effect of the Tyr-O-phosphate group is responsible for suppression of the ion-pairing interaction of the mobile phase counter ions with the positively charged terminal amino group of enkephalins.


Assuntos
Peptídeos Opioides/isolamento & purificação , Sequência de Aminoácidos , Ácidos Carboxílicos/análise , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Encefalinas/análise , Indicadores e Reagentes , Dados de Sequência Molecular , Fosforilação
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