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61.
High intra-population genetic diversity and multiple measures of genetic variability at STR loci are useful in inferring past evolutionary history. However, STRs, categorized by their repeat motif size, differ in a number of aspects, requiring separate analyses. We analyzed 783 STRs in 36 worldwide populations to examine marker suitability as well as correlations between various measurements, to evaluate the extent of genomic diversity present in modern human populations. The loci were grouped by type and analyzed separately for each population group. Genetic variation defined by gene diversity and allele size variance, shows different trends of variation across four types of STRs. Additionally, there is little variation of genetic diversity, but there is decreased allelic size variance with increasing repeat motifs. A poor correlation between genetic diversity and allelic size variance across loci in all groups for Di-STRs is probably caused by the presence of allelic size gaps. In contrast, allelic size variance, genetic diversity, and number of alleles are strongly correlated with both tri- and tetra-STRs. The positive correlation of allelic size variance and presence of gaps within the range of allelic sizes in Di-STRs alone explains these observations. An unexpected high imbalance index (β) at Di-STRs due to high allelic size variance also supports this assertion. 相似文献
62.
Dinesh Pathak Barunoday Chakraborty Sebanti Goswami Sudhir Adhikari 《Journal of obstetrics and gynaecology of India》2011,61(2):161-165
Objective
To study the difference in causes of maternal deaths at two tertiary centers one being rural and the other urban.Methods
A five years retrospective study from January 2001 to December 2005. Results: The maternal mortality ratio has decreased at Eden (6.09 to 2.81/1000 live births) and risen at Bankura (2.68 to 4.18/1000 live births) over the last five years. Most of the deaths were in the age group of 21–30 (65.48% and 60.62%) and unbooked (81.14% and 67.71%) at Eden and Bankura respectively. Greater number of deaths were noted in early puerperium (68.58% vs. 37.79%) and in multigravidas (71.68% vs. 50.78%) at Eden. Sepsis (30.70%) and jaundice (30.08%) were the major causes of death at Bankura and Eden respectively. Death due to toxaemia has gradually decreased.Conclusion
Majority of the deaths are preventable by proper antenatal care, counseling and asepsis practice. Antenatal care and EmOC are complementary to each other in reducing maternal mortality. 相似文献63.
Paramita Chakraborty Satyajit Das Kaushik Banerjee Abhinaba Sinha Susmita Roy Mitali Chatterjee 《Immunopharmacology and immunotoxicology》2014,36(2):165-175
Myeloid-derived suppressor cells (MDSCs), one of the major orchestrators of immunosuppressive network are present in the tumor microenvironment suppress antitumor immunity by subverting Th1 response in tumor site and considered as a great obstacle for advancement of different cancer immunotherapeutic protocols. Till date, various pharmacological approaches have been explored to modulate the suppressive functions of MDSCs in vivo. The present study describes our endeavor to explore a possibility of eradicating MDSCs by the application of a copper chelate, namely copper N-(2-hydroxy acetophenone) glycinate (CuNG), previously found to be a potential immunomodulator that can elicit antitumorogenic Th1 response in doxorubicin-resistant EAC (EAC/Dox) bearing mice. Herein, we demonstrated that CuNG treatment could reduce Gr-1+CD11b+ MDSC accumulation in ascitic fluid and spleen of EAC/Dox tumor model. Furthermore, we found that CuNG mediated reduction in MDSCs is associated with induction of Th1 response and reduction in Treg cells. Moreover, we observed that CuNG could deplete MDSCs by inducing Fas-FasL mediated apoptotic cell death where death receptor Fas expression is enhanced in MDSCs and FasL is provided by activated T cells. However, MDSC expansion from bone marrow cells and their differentiation was not affected by CuNG. Altogether, these findings suggest that the immunomodulatory property of CuNG is attributed to, at least in part, by its selective cytotoxic action on MDSCs. So, this preclinical study unveils a new mechanism of regulating MDSC levels in drug-resistant cancer model and holds promise of translating the findings into clinical settings. 相似文献
64.
65.
CT‐guided aspiration cytology of advanced silicosis and confirmation of the deposited zeolite nano particles through X ray diffraction: A novel approach 下载免费PDF全文
Arghya Bandyopadhyay M.D. Kaushik Majumdar M.D. D.N.B. Abhijit Chakraborty PH.D. Partha Mitra PH.D. Subhomoy Nag M.D. 《Diagnostic cytopathology》2016,44(3):246-249
Silicosis is a common occupational lung disease, resulting in fibrotic nodular lesions in the upper lobes of the lung parenchyma. Most of the pneumoconioses are diagnosed on the basis of relevant history and clinico‐radiological correlation. Image‐guided aspiration cytology appears to be poorly yielding and is not usually considered as a diagnostic modality. However, silicosis may sometimes offer a diagnostic challenge because of its radiological resemblance and clinical overlap with pulmonary tuberculosis and neoplastic lesions. We present a unique situation where image‐guided fine needle aspiration cytology (FNAC) has been advised on the basis of nodular upper lobe opacities. The cytology smears revealed hypocellular granular material, while phase contrast and polarized light microscopy highlighted crystalline particles. History of silica dust exposure long back was available after the cytological evaluation, suggesting the diagnosis of pulmonary silicosis. X ray diffraction (XRD) crystallography was also possible on cytology smears, confirming zeolite nano particles of size as small as 40 ? 50 nm as the concerned agent for the first time. Cytological evaluation by phase contrast and polarized light microscopy may be useful for the confirmation of silicosis, supplemented by clinical history and radiological evaluation. XRD on smears may help in determination of chemical nature and particle size. Diagn. Cytopathol. 2016;44:246–249. © 2015 Wiley Periodicals, Inc. 相似文献
66.
Large B-cell lymphomas (LBCLs) have significant false-negative results when immunophenotyped by flow cytometry (FC). To clarify the role fine-needle aspiration (FNA) in reducing this false-negative rate, 28 cases ultimately diagnosed as LBCL that had FNA as part of the workup and a negative FC were identified. We examined their clinical and cytologic features, in comparison with cases of LBCL with FNAs that were positive by FC. In 24/28 FC-negative cases (86%) a cytologic diagnosis of suspicious or positive for malignancy was rendered. We conclude that cytologic analysis is more sensitive than FC in the diagnosis of malignancy in FNA of LBCL, particularly in aspirates with low cellularity and/or low viability. Examination of cytospin preparations of the actual material analyzed by FC may provide an indication that an FC result is falsely negative. It is important to recognize the potential of false-negativity by FC of LBCLs when interpreting FNAs with features suggesting lymphoma. 相似文献
67.
Braverman N Chen L Lin P Obie C Steel G Douglas P Chakraborty PK Clarke JT Boneh A Moser A Moser H Valle D 《Human mutation》2002,20(4):284-297
PEX7 encodes the cytosolic receptor for the set of peroxisomal matrix enzymes targeted to the organelle by the peroxisome targeting signal 2 (PTS2). Mutations in PEX7 cause rhizomelic chondrodysplasia punctata (RCDP), a distinct peroxisome biogenesis disorder. In previous work we described three novel PEX7 mutant alleles, including one, L292X, with a high frequency due to a founder effect. We have now extended our analysis to 60 RCDP probands and identified a total of 24 PEX7 alleles, accounting for 95% of the mutant PEX7 genes in our sample. Of these, 50% are L292X, 13% are IVS9+1G>C, and the remainder are mostly private. IVS9+1G>C occurs on at least three different haplotypes and thus appears to result from recurrent mutation. The phenotypic spectrum of RCDP is broader than commonly recognized and includes minimally affected individuals at the mild end of the spectrum. To relate PEX7 genotype and phenotype, we evaluated the consequence of the disease mutation on PEX7 RNA by Northern analysis and RT/PCR. We evaluated the function of the encoded Pex7 protein (Pex7p) by expressing selected alleles in fibroblasts from RCDP patients and assaying their ability to restore import of a PTS2 marker protein. We find that residual activity of mutant Pex7p and reduced amounts of normal Pex7p are associated with milder and variant phenotypes. 相似文献
68.
Ricardo M. Cerda‐Flores Maria C. Villalobos‐Torres Hugo A. Barrera‐Saldaa Lizette M. Corts‐Prieto Leticia O. Barajas Fernando Rivas Angel Carracedo Yixi Zhong Sara A. Barton Ranajit Chakraborty 《American journal of human biology》2002,14(2):257-263
This study compares genetic polymorphisms at the D1S80 and HLA‐DQA1 loci in three Mexican Mestizo populations from three large states (Nuevo León, Jalisco, and the Federal District). Allele frequency distributions are relatively homogenous in the three samples; only the Federal District population shows minor differences of the HLA‐DQA1 allele frequencies compared with the other two. In terms of genetic composition, these Mestizo populations show evidence of admixture with predominantly Spanish‐European (50–60%) and Amerindian (37–49%) contributions; the African contribution (1–3%) is minor. Together with the observation that in Nuevo León, the admixture estimates based on D1S80 and HLA‐DQA1, are virtually the same as those reported earlier from blood group loci, suggests that DNA markers, such as D1S80 and HLA‐DQA1 are useful for examining genetic homogeneity/heterogeneity across Mestizo populations of Mexico. The inverse relationship of the proportion of gene diversity due to population differences (Gst) to within population gene diversity (Hs) is also consistent with theoretical predictions, supporting the use of these markers for population genetics studies. Am. J. Hum. Biol. 14:257–263, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
69.
The authors compared two methodological approaches, Jackknife ROC and JAFROC, in analyzing data ascertained during FROC (free-response receiver operating characteristics) type studies. Observer rating data obtained from two observer performance studies were analyzed. During the first study, seven radiologists interpreted 120 mammography examinations depicting 57 masses under five different conditions with and without the results of computer-aided detection (CAD). In the second study, eight radiologists interpreted 110 examinations depicting 51 masses under six different display conditions with and without CAD results. Readers rated the detection task in a FROC type response. Jackknife ROC (using the software of LABMRMC with the highest rating per case) and JAFROC were used to compute differences, if any, in summary performance levels among all reading modes in each study as well as for all paired data sets. The results of the different analytical approaches are compared. The overall results for all modes were significantly different for the first study (p < 0.05) and not significant (p > 0.05) for the second study using either analytical approach. In the first study, the performance levels represented by three paired data sets were significantly different (p < 0.05) when computed using LABMRMC and four pairs were significantly different (p < 0.05) using JAFROC. In eight of ten pairs, JAFROC produced lower p values than LABMRMC. In the second study, LABMRMC showed no significant differences for any paired data sets and JAFROC showed a significant difference for one pair. In 15 of 16 pairs, p values computed by JAFROC were lower than those computed by LABMRMC. 相似文献
70.
Paola Paglia Ivano Arioli Nicole Frahm Trinad Chakraborty Mario P. Colombo Carlos A. Guzmn 《European journal of immunology》1997,27(6):1570-1575
Listeria monocytogenes has been proposed as a carrier to elicit major histocompatibility complex class-I restricted immune responses able to protect against tumor challenge. In this study the properties of the attenuated L. monocytogenes Δmpl2 mutant has been evaluated in vivo against a highly aggressive mouse fibrosarcoma which expresses β-galactosidase (β-gal) as a tumor-associated antigen (TAA). Immunization with the vaccine prototypes resulted in both elicitation of specific antibodies and generation of cytotoxic lymphocytes (CTL). Oral vaccination protected 55–64% of the immunized animals from tumor take (p < 0.01) and strongly reduced the average size of the tumor in the other 34–45% (p < 0.01). Vaccinated mice developed a long-lasting response, which resulted in 100% protection from a subsequent tumor challenge. Substitution of the whole TAA by its CTL-defined immunodominant epitope resulted in 43% protection, suggesting a contribution of the humoral response to the observed antitumor effect. No statistically significant differences were observed in the antitumor response when mice were immunized with strains expressing the immunodominant TAA epitope in the context of carrier proteins which were either exported or restricted to the bacterial cytoplasm. This suggests that the topology of the recombinant antigen does not play a major role in the outcome of the protective response. 相似文献