Publications by authors named "Chakraborty M"

Radiotherapy is one of the most successful cancer therapies. Here the effect of irradiation on antigen presentation by MHC class I molecules was studied. Cell surface expression of MHC class I molecules was increased for many days in a radiation dose-dependent manner as a consequence of three responses.

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Thermoresponsive gold nanoparticles (GNPs) have been prepared by the borohydride reduction of gold salt in the presence of water-soluble polymer, poly(vinyl methyl ether) (PVME). The PVME-coated GNPs (PVME-GNPs) have been assembled into large aggregates in the presence of polyelectrolytes, viz., poly(sodium-4 styrene sulfonate) and sodium salt of carboxymethylcellulose at low pH by raising the solution temperature from 20 to 40 degrees C.

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For the immune system to mount an effective antitumor T-cell response, an adequate number of T-cells specific for the antigens expressed by the malignancy must be activated [1]. Since most antigens expressed by tumors are "self"-antigens, tumor antigens often lack endogenous immunogenicity and thus do not sufficiently activate T-cells to levels that can mediate tumor eradication. In addition, virtually all solid tumor cells lack the costimulatory molecules necessary to activate tumor-specific T-cells.

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Histopathological and mycobacteriological examinations have limited utility in the diagnosis of genital tuberculosis. In this double-blind study, 61 samples, consisting of endometrial aspirates (EAs), endometrial biopsies (EBs) and fluid from the pouch of Douglas (POD), from 25 women suffering from infertility were investigated for the presence of the mpt64 gene of Mycobacterium tuberculosis by PCR and correlated with laparoscopic findings. PCR demonstrated M.

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A seroepidemiological study was conducted to determine the hepatitis B virus carrier rate and infectivity status among antenatal patients in Calcutta. Fifteen of 400 antenatal mothers (3.74%) were carriers of HBV genotype D.

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This paper reports the detection and identification of phenolic metabolites (C6-C3 and C6-C1 compounds) in Cocos nucifera. An HPLC/UV system was used to analyze the soluble and wall-associated phenolics in mesocarp and leaf tissues of C. nucifera.

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Gatifloxacin is a broad spectrum fluoroquinolone that offers enhanced Gram-positive activity and anaerobic coverage to other fluoroquinolones. The pharmacokinetic parameters (Cmax, AUCo-t, tmax) of this drug have been evaluated to compare the single dose (400mg) bioavailability of gatifloxacin with the reference formulation. High performance liquid chromatography (HPLC) coupled with U-V detector set at 290 nm has been used to determine plasma concentration of 12 human volunteers as per DCGI (Drug Controller General of India) guidelines.

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This work deals with multisensor data fusion to obtain landcover classification. The role of feature-level fusion using the Dempster-Shafer rule and that of data-level fusion in the MRF context is studied in this paper to obtain an optimally segmented image. Subsequently, segments are validated and classification accuracy for the test data is evaluated.

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Newly developed sildenafil citrate (SC), a selective inhibitor of cyclic guanosine monophosphate (c-GMP) specific phosphodiesterase type 5 (PDE 5) in the corpus cavernosum is used for the oral treatment of erectile dysfunction. A convenient, sensitive and simple method for the determination of sildenafil in human plasma is presented. The analytical technique was based on reversed-phase high-performance liquid chromatography coupled with UV detector set at 295 nm.

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Recent studies in both animal models and clinical trials have demonstrated that the avidity of T cells is a major determinant of antitumor and antiviral immunity. In this study, we evaluated several different vaccine strategies for their ability to enhance both the quantity and avidity of CTL responses. CD8(+) T cell quantity was measured by tetramer binding precursor frequency, and avidity was measured by both tetramer dissociation and quantitative cytolytic function.

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A cross-sectional study carried out among 370 school-going children of the Nepali community, aged 5-10 years, in the Siliguri subdivision of Darjeeling district revealed the prevalence of parasitic infestation to be 51.4 per cent of which 28.2% and 23.

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Water-dispersible gold nanoparticles (GNPs) were synthesized by the polymer in situ redox technique at room temperature using poly(4-vinylphenol) (PVPh) as a simultaneous template/stabilizer and reducing agent. GNPs were characterized by its surface plasmon absorption peak at 536 nm. The average particle size of the gold-poly(4-vinylphenol) (Au-PVPh) nanocomposites decreases with increase in the ratio of PVPh to gold salt.

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Local radiation of tumor masses is an established modality for the therapy of a range of human tumors. It has recently been recognized that doses of radiation, lower than or equal to those that cause direct cytolysis, may alter the phenotype of target tissue by up-regulating gene products that may make tumor cells more susceptible to T-cell-mediated immune attack. Previously, we demonstrated that radiation increased Fas (CD95) gene expression in carcinoembryonic antigen (CEA)-expressing murine tumor cells, which consequently enhanced their susceptibility to CEA-specific CTL-mediated killing.

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When the third instar larvae of M. separata were exposed to eight varying concentrations of polyhedral occlusion bodies (POB's) of nucleopolyhedrovirus of M. separata (MsNPV) ranging from 2.

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Article Synopsis
  • Local radiation therapy for tumors can enhance their vulnerability to T-cell attacks by changing the tumor's characteristics, making it an effective strategy combined with vaccine therapy.
  • In a study using mice with human carcinoma models, combining local radiation (8-Gy) with a specific vaccine regimen led to significant tumor cures, mediated by the Fas/Fas ligand pathway.
  • The combination therapy resulted in a strong infiltration of T cells into tumors and elicited specific immune responses against multiple tumor antigens, suggesting a new approach to fighting established tumors through local irradiation and vaccination.
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Core-shell composite nanoparticles consisting of a gold core and polypyrrole shell were prepared and stabilized with the poly(amidoamine) dendrimer. An in situ redox polymerization technique was used in which pyrrole reduced Au3+ to Au and then oxidized to polypyrrole. The presence of gold nanoparticles as a core was characterized by its surface plasmon absorption peak at 534 nm.

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We report a comprehensive statistical analysis of data on 58 DNA markers (mitochondrial [mt], Y-chromosomal, and autosomal) and sequence data of the mtHVS1 from a large number of ethnically diverse populations of India. Our results provide genomic evidence that (1) there is an underlying unity of female lineages in India, indicating that the initial number of female settlers may have been small; (2) the tribal and the caste populations are highly differentiated; (3) the Austro-Asiatic tribals are the earliest settlers in India, providing support to one anthropological hypothesis while refuting some others; (4) a major wave of humans entered India through the northeast; (5) the Tibeto-Burman tribals share considerable genetic commonalities with the Austro-Asiatic tribals, supporting the hypothesis that they may have shared a common habitat in southern China, but the two groups of tribals can be differentiated on the basis of Y-chromosomal haplotypes; (6) the Dravidian tribals were possibly widespread throughout India before the arrival of the Indo-European-speaking nomads, but retreated to southern India to avoid dominance; (7) formation of populations by fission that resulted in founder and drift effects have left their imprints on the genetic structures of contemporary populations; (8) the upper castes show closer genetic affinities with Central Asian populations, although those of southern India are more distant than those of northern India; (9) historical gene flow into India has contributed to a considerable obliteration of genetic histories of contemporary populations so that there is at present no clear congruence of genetic and geographical or sociocultural affinities.

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Glyphosate is a nonselective herbicide used as a harvest aid in a variety of crops. Glyphosate is absorbed into the foliage and translocated to metabolically active regions in the plant where it interferes with the shikimic acid pathway. Experiments were conducted to determine the accumulation and distribution of shikimic acid in wheat treated with glyphosate at soft and hard dough stages of kernel development and to determine the fate of shikimic acid during milling and bread making.

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Article Synopsis
  • CD8(+) CTL are crucial in fighting cancer through both active and passive immunotherapy, but their effectiveness can be enhanced with additional treatments.
  • Radiotherapy has been shown to increase Fas gene expression in cancer cells, which can improve how well CTL can target and kill these cells.
  • In mouse models, exposing adenocarcinoma cells to low doses of radiation boosted Fas expression and significantly improved the antitumor activity of CTL, suggesting that combining immunotherapy with radiotherapy could lead to better outcomes in cancer treatment.
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A long-existing geochemical problem is the lack of a means of chemically defining non-stoichiometric complex minerals such as clays, which have no distinct composition and no clear compositional boundaries. We propose here a novel approach for describing the chemical nature of clay minerals using fuzzy logic. This non-conventional mathematical approach allows us to quantify compositional vagueness in such systems.

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Background: Although chronic hepatitis B occurs in hepatitis B e antigen (HBeAg)-negative patients, its prevalence and clinical significance are not known.

Aim: To determine the prevalence and profile of HBeAg-negative chronic hepatitis B virus (HBV) infection.

Methods: A retrospective analysis of 363 consecutive patients (mean age 36 y; 288 men) with chronic HBV infection was performed.

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The high-yield, general, one-pot synthesis of substituted isoindolequinones, a group of important radiosensitizers which sensitize hypoxic cells to the lethal effect of radiation in cancer radiotherapy, is described. Primary amines react with 2,3-bis[2-(trimethylsilyl)ethynyl]-5,6-dimethylhydroquinone (2) in methanol at room temperature under an inert atmosphere to give substituted isoindolequinones 2-alkyl-1,3,5,6-tetramethylisoindole-4,7-quinone (4) in almost quantitative yields. Moderate yields of 4 are also obtained using 2,3-diethynyl-5,6-dimethylhydroquinone (3) and amines as reactant and solvent under the similar conditions.

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