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121.
Utility of imprint cytology for early presumptive diagnosis in clinically suspicious cervical cancer
OBJECTIVE: To determine the utility of imprint cytology (IC) in providing an early presumptive diagnosis of clinically suspected cervical carcinoma. STUDY DESIGN: A total of 219 clinically suspicious cervical cancer cases underwent Pap test, punch biopsy and IC at the same sitting. Correlations were performed between these diagnostic modalities to determine the sensitivity and specificity of IC in diagnosis of cervical cancer. RESULTS: The overall accuracy of IC in detecting cervical cancers was 96.2%. About 78% of squamous cell carcinomas (SCC), 60% of adenocarcinomas and 100% of small cell carcinoma could be accurately typed on imprints. Twelve malignant lesions were diagnosed on IC among 26 unsatisfactory biopsies. Although there was no false positive result, 3.5% false negative diagnoses were given on IC. The sensitivity and specificity of imprint smear cytology to detect malignancy was 96.2% and 100%. Agreement between imprint cytology and Pap smear diagnosis of malignancy was 95.3%. kappa Statistics revealed excellent agreement between imprints and biopsies and between imprints and Pap smears in diagnosis of malignant lesions. CONCLUSION: IC can be used as an adjunctive technique for an early and reliable preliminary presumptive diagnosis of cancer of the uterine cervix. 相似文献
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Kaushik Ghosh Rajagopal Chattopadhyaya 《Journal of biomolecular structure & dynamics》2013,31(4):557-567
Abstract The circular dichroism spectra of three different purified carboxy terminal fragments 93–236, 112–236 and 132–236 of the bacteriophage γ cI repressor have been measured and compared with those of the intact repressor and the amino terminal fragment 1–92. All three carboxy terminal fragments contain mostly β-strands and loops, a minor helix content increasing with the size of the fragment, showing that the 93–131 region previously called a hinge is structured. Fourier transformed infrared spectra also showed that fragment 93–236 contains α-helices, β-sheets and turns but fragment 132–236 contains no detectable α-helix, only β-sheets and turns. Papain is known to cleave the γ repressor, but it is shown here that it cannot cleave the operator-bound repressor dimer. For the 132–236 fragment, both the wt and the SN228 mutant previously shown to be dimerization defective in the intact, gave similar dimerization properties as investigated by HPLC at 2 to 100 µM protein concentration, with a KD of 13.2 µM and 19.1 µM respectively. The papain cleavage for wt and SN228 proceed at equal rates for the first cleavage at 92–93; however, the subsequent cleavages are faster for SN228. The three Cys residues in the 132–236 fragment were found to be unreactive upon incubation with DTNB, indicating the thiol sulfur atoms are buried in the repressor carboxy terminal domain. Denaturation of the 132–236 fragment studied by tryptophan fluorescence shows two transitions centered at 1.5 M and 4.5 M of urea. 相似文献
125.
The analysis of diallel crosses by including the components due to maternal effect and maternal interaction effects have been presented for Griffing method—1 (random effect model) and Griffing method—3 (fixed and random effect model). Wherever exact test of significance is not possible, testing procedure using Satterthwaite (1946) approximation has been presented. 相似文献
126.
Clustered Regularly Interspaced Short Palindromic Repeats‐ C RISPR a ssociated (CRISPR‐Cas) systems present in genomes of bacteria and archaea have been the focus of many research studies recently. The Cas4 proteins of these systems are thought to be responsible for the adaptation step in the CRISPR mechanism. Cas4 proteins exhibit low sequence similarity among themselves and are currently classified into 2 main classes: DUF83 and DUF911. The characteristic features of Cas4 proteins belonging to DUF83 class have been elucidated by determining the structures of Cas4 protein from Sulfolobus solfataricus and Pyrobaculum calidifontis. Although, both Cas4 proteins characterized structurally are of same DUF83 class, these 2 proteins do exhibit significant biochemical and functional differences. The aim of the present study was to explore the structural and evolutionary features responsible for these differences. Our study predicts residues which might be responsible for such differences. Functional divergence analysis was used to predict sites exhibiting type I divergence, where certain amino acids are conserved in 1 clade whereas the same site is highly variable in the other clade. Our intra‐molecular interaction analysis reinforces the influence of such divergence sites on the other functionally important amino acids. In general, this study identifies some of the divergence hotspots that could be the focus of future experimental studies for better understanding of Cas4 enzymatic activity in CRISPR mechanism. 相似文献
127.
Kaushik Chattopadhyay Guillaume Fournié Md. Abul Kalam Paritosh K. Biswas Ahasanul Hoque Nitish C. Debnath Mahmudur Rahman Dirk U. Pfeiffer David Harper David L. Heymann 《EcoHealth》2018,15(1):63-71
Avian influenza is a major animal and public health concern in Bangladesh. A decade after development and implementation of the first national avian influenza and human pandemic influenza preparedness and response plan in Bangladesh, a two-stage qualitative stakeholder analysis was performed in relation to the policy development process and the actual policy. This study specifically aimed to identify the future policy options to prevent and control avian influenza and other poultry-related zoonotic diseases in Bangladesh. It was recommended that the policy should be based on the One Health concept, be evidence-based, sustainable, reviewed and updated as necessary. The future policy environment that is suitable for developing and implementing these policies should take into account the following points: the need to formally engage multiple sectors, the need for clear and acceptable leadership, roles and responsibilities and the need for a common pool of resources and provision for transferring resources. Most of these recommendations are directed towards the Government of Bangladesh. However, other sectors, including research and poultry production stakeholders, also have a major role to play to inform policy making and actively participate in the multi-sectoral approach. 相似文献
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129.
Rabindranath Ray Kaushik Ray Chinmay K. Panda 《Molecular and cellular biochemistry》1997,177(1-2):79-88
The uridylic acid rich nuclear RNAs (U1-U6 snRNAs) are involved mainly in the processing of pre-mRNA and pre-rRNA. So, any control of cell growth through pre-mRNA/pre-rRNA processing may have some regulation through altered UsnRNAs metabolism. With this idea, attempts have been made to see how the metabolism of the six major UsnRNAs' changed during the normal process of cellular proliferation associated with differentiation from pluripotent/totipotent stem cells of early embryonic stage to much more differentiated state of different cell/tissue lineages in different tissues/organs during the fetal and neonatal stages of growth. It has been seen that the levels of the six major UsnRNAs were high in day 8 embryo when the cells were mainly pluripotent/totipotent in nature, and during the progression of embryonic development the levels of these UsnRNAs gradually decreased (35-65%) up to the midgestational period (day 13) with some exception, when the organogenesis has already been started. However in the fetal life, the levels of these UsnRNAs were maximum or comparable around 18 ± 2 days of gestation in comparison to that in day 8 embryo when the kinetics of the maturational status of the different organs were quite high. But, the levels of these UsnRNAs' became low during day 21 of fetal life or in day 0 of birth (perturation period) in all the tissues/organs except high UsnRNAs' level in spleen. In the neonatal life, around 3 ± 1 days of birth these UsnRNAs' levels again became maximum in all the tissues/organs (except in thymus) followed by decrease up to 5/6 days, and to become steady with slight increase within one to two weeks, when the kinetics of the organ maturation reached to a steady state. In case of thymus, the levels of the U3-U6 snRNAs were high on day 0 of birth followed by decrease in their level on day 1/2 and then increased to become steady within 2-4 weeks; whereas the U1 and U2 snRNAs' levels were high on day 3 of birth and the subsequent changes were similar to that in other tissues/organs.Thus the different UsnRNAs' metabolism in the perturation period and in the early stages of neonatal life has indicated the differential cellular functions in these two stages of development. These alterations in the metabolism of these UsnRNAs might be due to the differential changes in the rate of synthesis of these UsnRNAs and/or with their differential turnover rate in the different stages of development. Also, the differential variations of these UsnRNAs' levels have been observed among the different tissues/organs at the respective stages of development indicating the differences in the UsnRNAs' metabolism among the different cell/tissue lineages. Thus, it can be concluded that the metabolism of these UsnRNAs were developmentally regulated with some cell/tissue lineage variations, which might have some role in the developmentally regulated cellular process of proliferation and differentiation, through altered RNA splicing and processing. 相似文献
130.
Control of skeletal muscle fibres and adipose cells size in the flesh of rainbow trout 总被引:3,自引:0,他引:3
B. Fauconneau S. Andre J. Chmaitilly P.-Y. Le Bail F. Krieg † S. J. Kaushik ‡ 《Journal of fish biology》1997,50(2):296-314
The distributions of the diameters of skeletal muscle fibres and adipocytes were studied in rainbow trout. The cellularity of perivisceral adipose tissues and subcutaneous ventral and dorsal adipose tissues were characterized more specifically. In these tissues, a population of small adipocytes was distinguishable from larger adipocytes. The same was observed in white muscle. The effects of extrinsic factors (dietary lipid in two different thermal conditions) and intrinsic factors (strains in two different saline conditions, growth hormone) on the long-term response of the cellularity of both muscle and adipose tissues were studied. The effects of thermal environment were tested on fish fed the same ration and the effects of saline environment on fish fed ad libitum. The mean size of white muscle fibres was relatively unaffected by the different treatments tested: genetic origin and dietary lipid in different environmental conditions. There were significant differences in growth rate due to genetic origin and saline environment. The possible involvement of hyperplasia in response to these different factors is discussed. Growth hormone supplementation enhanced the percentage of small diameter fibres indicating a role of this hormone in the control of muscle hyperplastic growth. The mean size of adipose cells was affected only slightly by the different treatments tested. An increase in adipose cell size with aging and lipid content was observed. The percentage of small adipocytes also increased with aging. Thus, it is proposed that the development of adipose tissues, and thus fat retention, both result from the recruitment of new adipocytes and from the increase in size of existing adipocytes. The hyperplastic process contributed significantly to the differences in fat retention due to different treatments tested (strains, thermal and saline environments). When partially substituting fish oils for corn oils in the diet, a large increase in the ventral adipose cell size was seen indicating a potential negative effect of n-6 fatty acids on cell proliferation. Growth hormone treatment, on the contrary, induced a decrease in the size of perivisceral adipocytes. Thus, diet and hormonal status affect adipose cells size through two different metabolic pathways: lipogenesis and lipolysis respectively. 相似文献