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71.
Sraboni Mitra Dipanjana Mazumder Indra Nilanjana Bhattacharya Ratnesh K. Singh Partha S. Basu Ranajit K. Mondal Anup Roy Eugene R. Zabarovsky Susanta Roychoudhury Chinmay K. Panda 《Genes, chromosomes & cancer》2010,49(2):155-170
To understand the importance of frequent deletion of 3p22.3 in cervical carcinogenesis, alterations (deletion/methylation/expression) of the candidate genes STAC, MLH1, ITGA9, and RBSP3, located in the region, were analyzed in 24 cervical intraepithelial neoplasia (CIN) and 137 uterine cervical carcinoma (CACX) samples. In CIN, RBSP3 deletion (48%) and methylation (26%) were high compared with the other genes (4–9%). In CACX, alterations of these genes were as follows: deletion: STAC (54%) > MLH1 (46%) > RBSP3 (45%) > ITGA9 (41%), methylation: RBSP3 (25%) > ITGA9 (24%) > STAC (19%) > MLH1 (13%). Overall, alterations of RBSP3 showed association with CIN, whereas for STAC and MLH1, this frequency increased significantly from CIN → Stage I/II and for ITGA9 from CIN → Stage I/II and also from Stage I/II → Stage III/IV. Quantitative mRNA expression analysis showed differential reduced expression of these genes in CACX concordant to their molecular alterations. The more active RBSP3B splice variant was underexpressed in CACX. RB1 was infrequently deleted in CACX. Concordance was seen between (i) inactivation of RBSP3 and intense p‐RB1 nuclear immunostaining and (ii) low/absence of MLH1 expression and its molecular alterations in CACX. In normal cervical epithelium, p‐RB1 immunostaining was low in differentiated cells, whereas MLH1 staining was seen in both nucleus and cytoplasm irrespective of differentiation stage. Alterations of the genes were significantly associated with poor prognosis. High parity (≥5)/early sexual debut (≤19 years) coupled with RBSP3 alterations/RB1 deletion predicted worst prognosis. Thus, inactivation of RBSP3 might be one of the early events in cervical carcinogenesis. © 2009 Wiley‐Liss, Inc. 相似文献
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Ryszard Buczynski Henry Bookey Mariusz Klimczak Dariusz Pysz Ryszard Stepien Tadeusz Martynkien John E. McCarthy Andrew J. Waddie Ajoy K. Kar Mohammad R. Taghizadeh 《Materials》2014,7(6):4658-4668
In this paper we report a two octave spanning supercontinuum generation in a bandwidth of 700–3000 nm in a single-mode photonic crystal fiber made of lead-bismuth-gallate glass. To our knowledge this is the broadest supercontinuum reported in heavy metal oxide glass based fibers. The fiber was fabricated using an in-house synthesized glass with optimized nonlinear, rheological and transmission properties in the range of 500–4800 nm. The photonic cladding consists of 8 rings of air holes. The fiber has a zero dispersion wavelength (ZDW) at 1460 nm. Its dispersion is determined mainly by the first ring of holes in the cladding with a relative hole size of 0.73. Relative hole size of the remaining seven rings is 0.54, which allows single mode performance of the fiber in the infrared range and reduces attenuation of the fundamental mode. The fiber is pumped into anomalous dispersion with 150 fs pulses at 1540 nm. Observed spectrum of 700–3000 nm was generated in 2 cm of fiber with pulse energy below 4 nJ. A flatness of 5 dB was observed in 950–2500 nm range. 相似文献
74.
S. Mitra S. Chatterjee C. K. Panda K. Chaudhuri K. Ray N. P. Bhattacharyya A. Sengupta S. Roychoudhury 《Annals of human genetics》2003,67(1):26-34
It has been proposed that a constellation of three TP53 polymorphisms (intron 3 16 bp duplication, codon 72 BstUI, and intron 6 Nci I RFLP at nt 13494) constitute a haplotype predictive of increased cancer risk. We have estimated the allele frequency of these polymorphisms in three endogamous Indian ethnic populations from three different geographic locations (viz. Iyer from south India, Brahmin from central India and Mahishya from eastern India), as well as in head and neck squamous cell carcinoma (HNSCC) patients, and in ethnically matched normal individuals from the eastern region of India. The genotype distributions and allele frequencies of the three polymorphisms in all but one population, as well as in patients, showed a good fit to Hardy‐Weinberg equilibrium. Strong linkage disequilibria were observed between all loci in every population examined, except for the 16bp‐Nci I haplotype in the Mahishya population. The Mahishya population differed significantly from the other two populations with respect to differences in allele frequency and haplotype frequency. Although there were no significant differences in genotypic frequency at any of the loci between HNSCC patients and the matched control population, the minor allele frequency of codon 72 and intron 3 16 bp polymorphisms showed significant variation. Variation in overall haplotype frequency between patients and normal individuals was significant (p = 0.036) when two rare haplotypes 2‐1‐2 and 1‐2‐1 were combined. The rare haplotype 2‐1‐2 was found to be modestly over represented in HNSCC patients as compared to normal individuals. 相似文献
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77.
Piya Roychoudhury Aleksandra Golubeva Przemysaw Dbek Micha Gloc Renata Dobrucka Krzysztof Kurzydowski Andrzej Witkowski 《Materials》2021,14(23)
Fabrication of flower-like nanostructures are gaining attention because of their high surface/volume ratio and extensive adsorption capacity. In the present investigation, flower-shaped, autofluorescent silver-silica (Ag-SiO2) hybrid nanoparticles have been fabricated exploiting diatoms as a source of nanosilica. Two different species of Gedaniella including G. flavovirens and G. mutabilis showed their efficacy in synthesizing fluorescent Ag-SiO2 nanoflowers (NFs) and nanospheres (NSs) against 9 mM silver nitrate solution, respectively. The biogenic nanoconjugate (Ag-SiO2) was characterized by Uv-vis spectroscopy, energy dispersive X-ray spectroscopy (EDS), scanning (SEM) and transmission (TEM) electron microscopy. Production of Ag-SiO2 hybrid nanoparticle was confirmed by observing both Ag and Si signals from a single nanoparticle in an EDS study. The broad and single absorption band at ~420 nm in Uv-vis spectroscopy confirmed proper miscibility and production of hybrid nanoparticles. The Ag-SiO2 nanohybrids revealed autofluorescent property under the blue light region (excitation ~450–490 nm). SEM images of particles synthesized by G. flavovirens revealed the production of microscopic flower shaped Ag-SiO2 particles with several layers of petals. A TEM study confirmed that the synthesized Ag-SiO2 NFs are variable in size with 100–500 nm in diameter. Decolorization of methylene blue after exposure to Ag-SiO2 particles confirmed catalytic activity of synthesized nanostructures. This eco-friendly method provides a new dimension in nanobiotechnology for biogenesis of such hierarchical nanostructure in a cost-effective way. 相似文献
78.
Chakrabarti S Sengupta S Sengupta A Basak SN Roy A Panda C Roychoudhury S 《Molecular carcinogenesis》2006,45(4):270-277
Intrinsic genomic instability of an incipient tumor cell drives the development of cancer. In colorectal cancer, an inverse relationship between microsatellite instability (MIN) and chromosomal instability (CIN) has been reported. The relationship between MIN and CIN in head and neck squamous cell carcinoma (HNSCC) is uncertain. In the present study, we examined these two types of instabilities in HNSCC using microsatellite markers and arbitrary primed PCR (APPCR) technique. HNSCC tumors showed high frequency of MIN and loss of heterozygosity (LOH). We observed that, in contrast to colorectal tumors, the frequency of LOH increased with the increase in MIN. There was no significant difference between MIN- and MIN+ groups of HNSCC tumors in the extent of overall genomic alterations; rather higher MIN+ tumors exhibited higher incidence of deletion. Thus, in sporadic HNSCC, both MIN and CIN pathways operate simultaneously to drive tumor formation. 相似文献
79.
Eric J. Chow Amanda M. Casto Reigran Sampoleo Margaret G. Mills Peter D. Han Hong Xie Brian Pfau Tien V. Nguyen Jaydee Sereewit Julia H. Rogers Sarah N. Cox Melissa A. Rolfes Constance Ogokeh Emily Mosites Timothy M. Uyeki Alexander L. Greninger James P. Hughes M. Mia Shim Nancy Sugg Jeffrey S. Duchin Lea M. Starita Janet A. Englund Pavitra Roychoudhury Helen Y. Chu 《Emerging infectious diseases》2022,28(11):2343
To determine the epidemiology of human parainfluenza virus in homeless shelters during the COVID-19 pandemic, we analyzed data and sequences from respiratory specimens collected in 23 shelters in Washington, USA, during 2019–2021. Two clusters in children were genetically similar by shelter of origin. Shelter-specific interventions are needed to reduce these infections. 相似文献
80.
Saurav Sarkar A. Roychoudhury B. K. Roychaudhuri 《Indian journal of otolaryngology and head and neck surgery》2010,62(2):118-120