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1.
World J Microbiol Biotechnol ; 37(11): 192, 2021 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-34637049

RESUMEN

In India, the tribal population constitutes almost 8.6% of the nation's total population. Despite their large presence, there are only a few reports available on Mycobacterium tuberculosis (M. tb) strain prevalence in Indian tribal communities considering the mobile nature of this population and also the influence of the mainstream populations they coexist within many areas for their livelihood. This study attempts to provide critical information pertaining to the TB strain diversity, its public health implications, and distribution among the tribal population in eleven Indian states and Andaman & Nicobar (A&N) Island. The study employed a population-based molecular approach. Clinical isolates were received from 66 villages (10 states and Island) and these villages were selected by implying situation analysis. A total of 78 M. tb clinical isolates were received from 10 different states and A&N Island. Among these, 16 different strains were observed by spoligotyping technique. The major M. tb strains spoligotype belong to the Beijing, CAS1_DELHI, and EAI5 family of M. tb strains followed by EAI1_SOM, EAI6_BGD1, LAM3, LAM6, LAM9, T1, T2, U strains. Drug-susceptibility testing (DST) results showed almost 15.4% of clinical isolates found to be resistant to isoniazid (INH) or rifampicin (RMP) + INH. Predominant multidrug-resistant (MDR-TB) isolates seem to be Beijing strain. Beijing, CAS1_DELHI, EAI3_IND, and EAI5 were the principal strains infecting mixed tribal populations across India. Despite the small sample size, this study has demonstrated higher diversity among the TB strains with significant MDR-TB findings. Prevalence of Beijing MDR-TB strains in Central, Southern, Eastern India and A&N Island indicates the transmission of the TB strains.


Asunto(s)
Etnicidad , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/genética , Tuberculosis Pulmonar/epidemiología , Tuberculosis Pulmonar/microbiología , Antituberculosos/farmacología , Proteínas Bacterianas/genética , Técnicas de Tipificación Bacteriana , ARN Polimerasas Dirigidas por ADN/genética , Farmacorresistencia Bacteriana , Farmacorresistencia Bacteriana Múltiple , Femenino , Genes Bacterianos , Humanos , India/epidemiología , Islas , Masculino , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/aislamiento & purificación , Filogenia , Prevalencia , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/microbiología
2.
Int J Biol Macromol ; 115: 540-546, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29679672

RESUMEN

An attempt has been made to demonstrate the effects of exfoliated tungsten disulfide (E-WS2) nanosheets on the fabrication, permeation and anti-fouling performance of cellulose acetate (CA) ultrafiltration membranes. The E-WS2 was prepared and characterized in terms of energy dispersive X-ray spectroscopy (EDXS) and X-ray diffraction spectroscopy (XRD). Pure and composite CA membranes were methodically characterized for its surface, chemical and morphological structure using FT-IR, XRD, SEM and water contact angle analysis. Filtration characteristics of membranes such as pure water flux, porosity and hydraulic resistance were also studied. The addition of E-WS2 nanosheets exhibited significant improvement in the surface hydrophilicity of composite membranes than the control CA membrane and are evidenced by the observed contact angle and porosity values. However at 1 wt% E-WS2 concentration, CA membrane showed lower water flux (92.3 ±â€¯0.5) due to the pore plugging effect. The flux recovery ratio (FRR), bovine serum albumin (BSA) rejection, reversible and irreversible fouling experimental results suggested that CA/E-WS2 (1 wt%) UF membranes possess better fouling resistance potential than control CA membrane as a result of enhanced hydrophilicity. This study emphasizes the strong interplay between CA and E-WS2 nanosheets which play a significant role in altering the permeation and antifouling characteristics of nanocomposite membranes.


Asunto(s)
Incrustaciones Biológicas/prevención & control , Celulosa/análogos & derivados , Membranas Artificiales , Nanoestructuras/química , Tungsteno/química , Animales , Bovinos , Celulosa/química , Celulosa/farmacología , Interacciones Hidrofóbicas e Hidrofílicas , Permeabilidad , Albúmina Sérica Bovina/química , Agua/química
3.
Int J Biol Macromol ; 107(Pt B): 1607-1612, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28988843

RESUMEN

Cellulose acetate (CA) nanocomposite ultrafiltration (UF) membranes were fabricated using 2D layered nanosheets such as graphene oxide (GO) and exfoliated molybdenum disulfide (E-MoS2) and effectively used for the removal of macromolecular protein. The GO and E-MoS2 nanosheets were prepared and characterized by FT-IR and XRD respectively. GO and E-MoS2 (0.5wt.%) were blended individually with CA. The assenting changes generated by the incorporation of GO and E-MoS2 in terms of surface hydrophilicity of the nanocomposite membrane were analyzed by pure water flux (PWF) and contact angle measurement. The influence of 2D nanosheets on the morphology of CA are studied by scanning electron microscopy (SEM). Mechanical strength and hydraulic resistance of the nanocomposite membranes were found to be improved compared to bare CA membrane. The separation and antifouling performance of the nanocomposite membranes were studied using macromolecular bovine serum albumin (BSA). From the results, it was observed that a CA/GO-0.5 membrane exhibited the highest PWF (125.4±1.7Lm-2h-1), water content (70.6±1.2%), porosity (34.6±1.7%), flux recovery ratio (FRR) (88.8±1.6%) and lowest contact angle (63.9±2.5°), hydraulic resistance (4.3±0.67kPa/Lm-2h -1) than pure CA and CA/E-MoS2-0.5 membranes. CA/GO-0.5 membrane displayed superior UF and antifouling performance due to the greater affinity of GO nanoparticles towards water.


Asunto(s)
Celulosa/análogos & derivados , Sustancias Macromoleculares/química , Membranas Artificiales , Nanocompuestos/química , Nanotecnología/métodos , Animales , Incrustaciones Biológicas , Bovinos , Celulosa/química , Disulfuros , Grafito , Interacciones Hidrofóbicas e Hidrofílicas , Molibdeno , Nanocompuestos/ultraestructura , Porosidad , Albúmina Sérica Bovina/química , Espectroscopía Infrarroja por Transformada de Fourier , Resistencia a la Tracción , Agua/química , Difracción de Rayos X
4.
Acta Crystallogr E Crystallogr Commun ; 72(Pt 5): 616-9, 2016 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27308002

RESUMEN

The asymmetric unit of the organic-inorganic title salt, (C10H28N4)[Cr2O7]2, comprises one half of an 1,4-bis-(3-ammonio-prop-yl)piperazinediium cation (the other half being generated by the application of inversion symmetry) and a dichromate anion. The piperazine ring of the cation adopts a chair conformation, and the two CrO4 tetra-hedra of the anion are in an almost eclipsed conformation. In the crystal, the cations and anions form a layered arrangement parallel to (001). N-H⋯O hydrogen bonds between the cations and anions and additional C-H⋯O inter-actions lead to the formation of a three-dimensional network structure.

5.
Artículo en Inglés | MEDLINE | ID: mdl-23583849

RESUMEN

Single crystals of zinc doped L-proline cadmium chloride monohydrate were successfully grown from aqueous solution by slow evaporation method at room temperature for different molar concentration of zinc chloride. The structural properties of grown crystals have been studied by single crystal X-ray diffraction, powder X-ray diffraction studies and Fourier transform infrared spectral analysis. The incorporation of the dopant (zinc chloride) into L-proline cadmium chloride monohydrate crystal lattice has been confirmed by EDAX analysis. UV-Vis spectral analyses showed that the doped crystals have lower UV cut-off wavelength at 200 nm combined with very good transparency about 85% in a very wide range. The second harmonic generation efficiency test has been carried out and results are discussed. The 0.2 and 0.4 mol Zinc chloride doped crystals were thermally stable up to 208.9 °C and 211.9 °C respectively. The electrical properties have been studied by dielectric constant studies. All results are compared with the results of pure L-PCCM crystals.


Asunto(s)
Cloruro de Cadmio/química , Cloruros/química , Prolina/química , Compuestos de Zinc/química , Cristalización , Cristalografía por Rayos X , Espectrofotometría Ultravioleta , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
6.
Ann Neurol ; 63(3): 366-76, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18074388

RESUMEN

OBJECTIVE: Human immunodeficiency virus-1 (HIV-1) causes mild to severe cognitive impairment and dementia. The transactivator viral protein, Tat, is implicated in neuronal death responsible for neurological deficits. Several clades of HIV-1 are unequally distributed globally, of which HIV-1 B and C together account for the majority of the viral infections. HIV-1-related neurological deficits appear to be most common in clade B, but not clade C prevalent areas. Whether clade-specific differences translate to varied neuropathogenesis is not known, and this uncertainty warrants an immediate investigation into neurotoxicity on human neurons of Tat derived from different viral clades METHODS: We used human fetal central nervous system progenitor cell-derived astrocytes and neurons to investigate effects of B- and C-Tat on neuronal cell death, chemokine secretion, oxidative stress, and mitochondrial membrane depolarization by direct and indirect damage to human neurons. We used isogenic variants of Tat to gain insights into the role of the dicysteine motif (C30C31) for neurotoxic potential of Tat RESULTS: Our results suggest clade-specific functional differences in Tat-induced apoptosis in primary human neurons. This study demonstrates that C-Tat is relatively less neurotoxic compared with B-Tat, probably as a result of alteration in the dicysteine motif within the neurotoxic region of B-Tat INTERPRETATION: This study provides important insights into differential neurotoxic properties of B- and C-Tat, and offers a basis for distinct differences in degree of HIV-1-associated neurological deficits observed in patients in India. Additional studies with patient samples are necessary to validate these findings.


Asunto(s)
Cisteína/genética , Productos del Gen tat/genética , Productos del Gen tat/toxicidad , VIH-1/clasificación , VIH-1/genética , Neuronas/patología , Secuencias de Aminoácidos/genética , Células Cultivadas , Humanos , Neuronas/fisiología , Neuronas/virología , Células Madre/patología , Células Madre/virología
7.
Eur J Vasc Endovasc Surg ; 14(6): 457-61, 1997 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9467520

RESUMEN

OBJECTIVES: To compare the findings of continuous wave Doppler (CWD) with duplex ultrasound in the assessment of primary and uncomplicated varicose veins, and to determine how their relative roles might be best applied. MATERIALS AND METHODS: One hundred consecutive limbs were studied in 73 patients with primary (no previous surgery) and uncomplicated (no significant skin change) varicose veins. CWD was employed by a single observer; followed by duplex scanning performed "blind" and independently. RESULTS: There were 87 limbs with long saphenous incompetence on duplex; all but four of which were correctly identified by CWD, by which technique there were no false positives. (Sensitivity 95%, specificity 100%.) There were 21 limbs with short saphenous incompetence on duplex, all but two of which were recognised on CWD. However, CWD incorrectly diagnosed reflux at the saphenopopliteal junction in five limbs (false positives) with what was, in fact, segmental reflux in the long saphenous trunk on duplex (sensitivity 90%, specificity 93%.) This would have led to inappropriate exploration of the saphenopopliteal junction had surgery proceeded without checking with duplex. CONCLUSIONS: CWD is adequate for long saphenous incompetence. All "reflux" demonstrated on CWD in the popliteal fossa (about 25% of cases) should be checked by duplex. If this policy had been followed, all the patients in this study would have undergone the correct procedure. The only "errors" would have been missing coexistent short saphenous incompetence in two limbs undergoing appropriate long saphenous exploration.


Asunto(s)
Ultrasonografía Doppler/métodos , Várices/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vena Safena/diagnóstico por imagen , Sensibilidad y Especificidad
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