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1.
Eur J Hum Genet ; 2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38538877

RESUMEN

Mutations in BRCA1 and BRCA2 significantly elevate the risk of developing breast and ovarian cancer. Limited data exists regarding the prevalence of BRCA mutations, and optimal, cost-effective testing strategies in developing countries like India. This study aimed to evaluate the utility of a Next Generation Sequencing (NGS) panel for BRCA1/2 mutation testing among women diagnosed with, or at risk of developing hereditary breast and ovarian cancers. We also aimed to identify population specific BRCA1/2 mutation hotspots, to enable the development of more affordable testing strategies. We identified 921 patients with breast and ovarian cancer who underwent mutation testing. The target enrichment was followed by targeted NGS in 772 patients and an allele-specific PCR (ASPCR) based genotyping for BRCA1:c.68_69delAG (or 185delAG), was carried out in 149 patients. We identified 188 (20.4%) patients with BRCA1/2 variants: 118 (62.8%) with pathogenic/likely pathogenic and 70 (37.2%) with VUS. The 185delAG was identified as a recurrent mutation in the Southern Indian population, accounting for 24.6% of the pathogenic variants. In addition, a family history of breast, ovary, pancreas, or prostate (BOPP) cancer was found to be associated with an increased risk of identifying a deleterious BRCA1/2 variant [OR = 2.11 (95% CI 1.45-3.07) p ≤ 0.001]. These results suggest that Targeted NGS is a sensitive and specific strategy for BRCA testing. For Southern Indian patients, a two-tiered approach can be considered: Initial screening with ASPCR for BRCA1 185delAG followed by NGS for those testing negative. Expanding the gene panel and identifying other population-specific mutation hot spots is a promising area with potential for improvements in testing and treatment strategies.

2.
Chemosphere ; 290: 133248, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34906523

RESUMEN

In this work, we have developed fluorescent detection techniques for the determination of Ni2+ ions in aqueous medium with sensitivity using metal coordinating fluorescent molecules namely 4-Halobenzylidene malanonitrile. The halogen substituted benzylidene malanonitile were synthesised Knoevenagel condensation reaction of various halogen substituted aromatic aldehydes with malanonitrile and products were characterised by IR and NMR spectroscopy. The obtained benzylidene malanonitiles and are exhibited a fluorescent emission with a peak of 430 nm, 440 nm and 448 nm for chloro, bromo and fluoro substituted compounds, respectively. The intensity of optical emission of the studied molecules is increased proportional to the addition of Ni2+ ions. The effect of different halogen substitution on the fluorescence behaviour of benylidene malononitrile has also been investigated. The synthesised title compounds showed a lowest detection limit of 10-20 M for the Nickel (II) ions in aqueous solution under UV-Vis absorption spectra. The molecule 4- Bromobenzylidene malanonitrile exhibited a lowest detection limit of 10-19 M for the Nickel (II) ions in, aqueous solution, photoluminescence analysis.


Asunto(s)
Níquel , Agua , Iones
3.
Chemosphere ; 289: 133223, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34896170

RESUMEN

The growing contamination of ecosystems necessitates the development of long-term pollution-removal technologies. Electrodeionization, in notably, has newly proven as an efficient method for removing ionic chemicals from polluted waterways. The fact that continuous electrodeionization is a greener technique is most probably the biggest cause for its success. It replaces the toxic chemicals typically required to replenish resins with electric power, therefore eliminating the wastewater involved with resin renewal. In water treatment, electrodeionization solves some of the drawbacks of ion exchange resin beds, particularly ion dumping as beds expire. This comprehensive review explores the theory, principles, and mechanisms of ion movement and separation in an electrodeionization unit. Also, it investigated the construction and usage, notably in removing heavy metal and its current developments in electrodeionization unit. Recent advances in Electrodeionization like polarity reversal, Resin wafer Electrodeionization, membrane free Electrodeionization, and electrostatic shielding with novel materials and hybrid process along with Electrodeionization were addressed. Further advancements are expected in electrodeionization systems that exhibit better efficacy while running at lower costs due to decreased energy usage, rendering them appealing for industrial scale up across a wide range of applications across the world.


Asunto(s)
Metales Pesados , Purificación del Agua , Ecosistema , Resinas de Intercambio Iónico , Aguas Residuales
4.
Environ Res ; 196: 110996, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33716028

RESUMEN

Existence of human beings in this world require a cleaner environment, in which, water is the main requirement for living. Owing to the considerable development in civilisation and considerable population explosion, an increase in the contamination of natural water resources by means of non-biodegradable contaminants like heavy metals is observed thereby increasing the need for treatment of water before usage. Despite the existence of specific limits for disposal of heavy metals in water resources, studies still show high contamination of heavy metals in all these water resources. This review provides a brief note on sources and toxicity of different heavy metals in various oxidation states, their effects as well as highlights the numerous available and advanced techniques for heavy metals removal. Of all techniques adsorption is found to be beneficial as it doesn't inculcate any secondary pollutants to the environment. Additionally, this article has investigated the advantages of polymer nanocomposites in adsorption and mainly focused on biopolymer chitosan owing to its abundance in natural environment. The cleaner techniques for the extraction of chitosan and its functionalisation using different types of nanofillers are comprehensively discussed in this review. This article suggests a better alternative for conventional adsorbents as well as aids in remediation of wastes.


Asunto(s)
Quitosano , Contaminantes Ambientales , Metales Pesados , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Humanos , Aguas Residuales , Contaminantes Químicos del Agua/toxicidad
5.
J Oral Maxillofac Pathol ; 24(1): 117-124, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32508459

RESUMEN

BACKGROUND: Head and neck cancer is the sixth most common cancer reported worldwide. In many cases, the level of aggressiveness of therapy adopted in cancer patients may cause the alteration in oral microbiota; the emergence of potential pathogens may cause opportunistic infections in already immune-compromised individuals leading to increases in morbidity and mortality. Hence, this study was conducted to assess the oral microbial profile in oral cancer patients before and after radiotherapy. MATERIALS AND METHODS: A total of 145 oral swabs were collected before radiotherapy (n = 96), 3 months postradiotherapy (n = 25), 6 months postradiotherapy (n = 12) and controls (n = 12). The samples were inoculated into brain-heart infusion broth and later in different media for bacterial isolation. The isolates were subjected to phenotypic characterization by automatic identification system. RESULTS: Among the 96 samples studied from the preradiotherapy patient samples, Streptococcus species (n = 28) were the predominant isolate, followed by Staphylococcus species (n = 16), Enterobacter species (n = 6) and Enterococcus species (n = 6). Of the 25 samples studied 3 months after radiotherapy, Klebsiella pneumoniae (n = 4) was isolated and 12 samples studied after 6 months of radiotherapy Candida species (n = 4) and Pediococcus species (n = 3) were isolated. Among the control group (n = 12) screened, Streptococcus acidominimus (n = 3) is the predominant bacteria isolated. CONCLUSION: High prevalence of Streptococcus sp. was found in patients of oral cancer before radiotherapy, while Candida albicans and Klebsiella species and Pediococcus species are the significant pathogens isolated in postradiotherapy cancer patients.

6.
Microb Pathog ; 102: 120-132, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27919625

RESUMEN

The present work reports the development of a Simple, rapid and eco-friendly route for the biosynthesis of gold and silver nanoparticles and their antimicrobial activity against gram positive and gram negative bacterial pathogens in the wound infected area. The synthesis was done using Mukia maderasapatna plant extract as a reducing agent. FT-IR analysis reported that the methanol extract was found to contain maximum number of functional groups which is responsible for the reduction of metal ions to metal nanoparticles. Further, the presence of bioactive molecules present in the methanol extract was confirmed by GC-MS analysis. The major phytochemical constituents observed in this Mukia maderaspatna leaf extract were n-hexadecanoic acid (15.51%), Octadecanoic acid (11.92%), stigmasterol (9.12%), Octadecanoic acid, 2, 3 hydroxypropyl ester (8.7%), Bicycloheptane, 2,6,6- trimethyl (5.57%) and stearic acid (4.23%). Initially, the formation of gold and silver nanoparticles was confirmed from their absorption spectra at 535 nm and 434 nm using UV- visible spectroscopy. The crystalline nature of the obtained gold and silver nanoparticles was confirmed by X-ray diffraction analysis. The average size of the gold and silver nanoparticles found around 50 nm and 20 nm respectively was confirmed by TEM analysis. The antimicrobial activities of silver and gold nanoparticles were checked against bacterial strains and the fungal strains. The formation of inhibition zones concluded that both the nanoparticles showed efficient antimicrobial activity against both the pathogens. Further, different concentrations of gold and silver nanoparticles, the antibiotics Ciprofloxacin and chloramphenicol as the positive control were carried out. The results concluded that the silver nanoparticles showed efficient activity against bacterial pathogens and fungal pathogens with the lowest concentration of 0.35 µg/ml and 0.45 µg/ml respectively.


Asunto(s)
Cucumis/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Análisis Espectral , Antiinfecciosos/química , Antiinfecciosos/farmacología , Cromatografía de Gases y Espectrometría de Masas , Oro/química , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Humanos , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/química , Pruebas de Sensibilidad Microbiana , Fitoquímicos/química , Fitoquímicos/farmacología , Plata/química , Espectroscopía Infrarroja por Transformada de Fourier
7.
Acta Biomater ; 36: 323-31, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26979480

RESUMEN

UNLABELLED: A new a biocompatible Ti42Zr40Ta3Si15 (atomic %) porous bulk glassy alloy was produced by combination of rapid solidification and powder metallurgy techniques. Amorphous alloy ribbons were fabricated by melt spinning, i.e. extremely fast quenching the molten alloy with 10(6)K/s from T=1973K down to room temperature. The ribbons were then cryo-milled at liquid nitrogen temperature in order to produce powder, which was subsequently hot pressed. The resulting thick pellets have a porosity of about 14vol%, a high compression strength of 337MPa and a Young's modulus of about E=52GPa, values very close to those characteristic of cortical bone. Moreover, the morphology of the samples is very similar to that of cortical bone. The biocompatibility, which is due to the absence of any toxic element in the chemical composition, together with the suitable mechanical behavior, make these samples promising for orthopedic and dentistry applications. STATEMENT OF SIGNIFICANCE: Ti-based alloys are nowadays the standard solution for biomedical implants. However, both the conventional crystalline and amorphous alloys have higher rigidity as the human bone, leading to the damage of the bone at the interface, and contains harmful elements like vanadium, aluminum, nickel or beryllium. The hierarchical porous structures based on glassy alloys with biocompatible elements is a much better alternative. This work presents for the first time the manufacturing of such porous bodies starting from Ti-based amorphous alloy ribbons, which contains only non-harmful elements. The morphology and the compressive mechanical properties of these new products are analyzed in regard with those characteristic to the cortical bone.


Asunto(s)
Aleaciones/química , Módulo de Elasticidad , Vidrio/química , Titanio/química , Humanos , Porosidad
8.
Materials (Basel) ; 9(5)2016 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-28773455

RESUMEN

Titanium-based bulk metallic glasses (BMGs) are considered to have potential for biomedical applications because they combine favorable mechanical properties and good biocompatibility. Copper represents the most common alloying element, which provides high amorphization capacity, but reports emphasizing cytotoxic effects of this element have risen concerns about possible effects on human health. A new copper-free alloy with atomic composition Ti42Zr10Pd14Ag26Sn8, in which Cu is completely replaced by Ag, was formulated based on Morinaga's d-electron alloy design theory. Following this theory, the actual amount of alloying elements, which defines the values of covalent bond strength Bo and d-orbital energy Md, situates the newly designed alloy inside the BMG domain. By mean of centrifugal casting, cylindrical rods with diameters between 2 and 5 mm were fabricated from this new alloy. Differential scanning calorimetry (DSC) and X-rays diffraction (XRD), as well as microstructural analyses using optical and scanning electron microscopy (OM/SEM) revealed an interesting structure characterized by liquid phase-separated formation of crystalline Ag, as well as metastable intermetallic phases embedded in residual amorphous phases.

9.
Spectrochim Acta A Mol Biomol Spectrosc ; 136 Pt B: 986-92, 2015 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-25459624

RESUMEN

A dye-sensitized solar cell based on a spray deposited zinc oxide (ZnO) photoanode with Evans blue as a sensitizer was fabricated. Structural analysis confirms the hexagonal wurtzite phase of the ZnO photoanode with c-axis orientation. Surface morphology of the ZnO photoanode shows uniform distribution of spherically-shaped grains, ranging from 18 nm to 25 nm. The power conversion efficiency of the device was measured as 0.1%. Density functional theory was adopted to study the observed photovoltaic performance of the fabricated device. The analysis of the electronic properties of Evans blue dye showed that it has a pronounced effect on the observed device performance.


Asunto(s)
Colorantes/química , Modelos Moleculares , Teoría Cuántica , Energía Solar , Óxido de Zinc/química , Electrodos , Electrones , Azul de Evans/química , Microscopía Electrónica de Rastreo , Conformación Molecular , Fenómenos Ópticos , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Vibración , Difracción de Rayos X
10.
Sensors (Basel) ; 13(2): 2164-75, 2013 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-23389346

RESUMEN

In this work mass loading sensitivity of a Sezawa wave mode based surface acoustic wave (SAW) device is investigated through finite element method (FEM) simulation and the prospects of these devices to function as highly sensitive SAW sensors is reported. A ZnO/Si layered SAW resonator is considered for the simulation study. Initially the occurrence of Sezawa wave mode and displacement amplitude of the Rayleigh and Sezawa wave mode is studied for lower ZnO film thickness. Further, a thin film made of an arbitrary material is coated over the ZnO surface and the resonance frequency shift caused by mass loading of the film is estimated. It was observed that Sezawa wave mode shows significant sensitivity to change in mass loading and has higher sensitivity (eight times higher) than Rayleigh wave mode for the same device configuration. Further, the mass loading sensitivity was observed to be greater for a low ZnO film thickness to wavelength ratio. Accordingly, highly sensitive SAW sensors can be developed by coating a sensing medium over a layered SAW device and operating at Sezawa mode resonance frequency. The sensitivity can be increased by tuning the ZnO film thickness to wavelength ratio.

11.
Indian J Med Microbiol ; 22(1): 34-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-17642683

RESUMEN

PURPOSE: Genevac B, a new indigenous recombinant hepatitis B vaccine was evaluated for its immunogenicity and safety in comparison with Engerix B (Smithkline Beecham Biologicals, Belgium) and Shanvac B (Shantha Biotechnics, India) in healthy adult volunteers. METHODS: While 240 study subjects were included in the Genevac B group, 80 each were the subjects for Engerix B and Shanvac B. A three dose regimen of 0,1,2 months was adopted with 20 gm dosage uniformly in all the three groups. Vaccinees were assessed during prevaccination, followup and post vaccination periods for clinical, haematological, biochemical and immunological parameters for safety and immunogenicity. RESULTS: Successful follow-up in all parameters for four months could be achieved in 92.5% (222/240) for Genevac B study subjects and the same was 85% (68/80) and 80% (64/80) for Engerix B and Shanvac B respectively. While 100% seroconversion was observed in all the three groups, the rate of seroprotectivity was 99.5% by Genevac B, 98.5% by Engerix B and 98.4% for Shanvac B. However the difference was not statistically significant (p>0.05). The GMT values of anti HBs after one month of completion of the vaccination were 735.50, 718.23 and 662.20 mIU/mL respectively. No systemic reaction was either seen or reported by the volunteers during the vaccination process of Genevac B and other two vaccines. Clinical, haematological and biochemical safety parameters remained within normal limits throughout the study period. CONCLUSION: The study confirms that Genevac B, the new recombinant Hepatitis B vaccine has the acceptable international standards of safety and immunogenicity.

12.
J Indian Med Assoc ; 100(6): 372-5, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12416669

RESUMEN

The efficacy of microbiological diagnosis in sexually transmitted diseases (STDs) has been evaluated in comparison with the clinical diagnosis. Amongst the clinical diagnoses of single STDs, syphilis, genital warts, gonorrhoea and herpes genitalis were the predominant ones. Syphilis was the most predominant infection in both the single and mixed STD infections in Chennai. Clinical diagnoses of trichomoniasis, genital chlamydiasis and genital herpes were more accurate and correlated well with laboratory investigations. On the other hand, clinical diagnoses of gonorrhoea, candidiasis and syphilis were less accurate. More over many of these cases, clinically diagnosed as single, infection, were also positive for other STDs in the laboratory investigations. Double infections were clinically diagnosed only in 7 cases as against 11 cases in microbiological tests and one triple infection diagnosed in microbiological tests was diagnosed only as single disease clinically. Therefore, the laboratory/microbiological investigations have been emphasised to have better accuracy of diagnosis of STDs.


Asunto(s)
Enfermedades de Transmisión Sexual/diagnóstico , Enfermedades de Transmisión Sexual/microbiología , Adolescente , Adulto , Distribución por Edad , Estudios de Cohortes , Femenino , Humanos , India/epidemiología , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Prevalencia , Factores de Riesgo , Sensibilidad y Especificidad , Distribución por Sexo , Enfermedades de Transmisión Sexual/epidemiología
13.
J Assoc Physicians India ; 49: 412-4, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11762609

RESUMEN

AIM OF THE STUDY: To study the clinical and immunological profile of mixed connective tissue disease (MCTD) in rheumatic disease population. METHODS: We retrospectively analyzed 6400 cases of rheumatic disease population who took treatment in the Department of Rheumatology, Madras Medical College, Chennai during the period of 1996 to 1999, in which eight cases fulfilled the preliminary diagnostic criteria of mixed connective tissue disease devised by Kasukawa et al. All eight cases were studied in detail. RESULTS: All cases were females between 23 to 50 years of age. Polyarthritis, Raynaud's phenomenon and sclerodactyly were present in all eight patients. Oesophageal abnormalities, pulmonary changes and myositis were present in six patients. Facial erythema was observed in five patients. Alopecia and oral ulcers were seen in four patients. Two patients had pulmonary hypertension and migraine like headache. One patient had diffuse proliferative glomerulonephritis as an interesting feature by renal biopsy. Pleuritis, pericarditis and trigeminal neuropathy with lower cranial nerve palsies were present in one case each. Immunological tests showed presence of antinuclear antibodies and anti U1 ribonucleoprotein (anti U1RNP) antibodies in all eight patients. CONCLUSIONS: Mixed connective tissue disease should be considered as an important syndrome in any patient who presents with heterogeneous clinical presentation and who do not fit into any definite criteria of systemic connective tissue disorders.


Asunto(s)
Enfermedad Mixta del Tejido Conjuntivo/diagnóstico , Enfermedad Mixta del Tejido Conjuntivo/inmunología , Adulto , Biopsia con Aguja , Endoscopía , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , India/epidemiología , Persona de Mediana Edad , Enfermedad Mixta del Tejido Conjuntivo/epidemiología , Pronóstico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X
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