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61.
Limtong S Jindamorakot S Am-In S Kaewwichian R Nitiyon S Yongmanitchai W Nakase T 《Antonie van Leeuwenhoek》2011,99(4):865-871
62.
Ram Krishna Thakur Vinod Kumar Yadav Akinchan Kumar Ankita Singh Krishnendu Pal Luke Hoeppner Dhurjhoti Saha Gunjan Purohit Richa Basundra Anirban Kar Rashi Halder Pankaj Kumar Aradhita Baral MJ Mahesh Kumar Alfonso Baldi Bruno Vincenzi Laura Lorenzon Rajkumar Banerjee Praveen Kumar Viji Shridhar Debabrata Mukhopadhyay Shantanu Chowdhury 《Nucleic acids research》2014,42(18):11589-11600
63.
Paulina Akeus Veronica Langenes Astrid von Mentzer Ulf Yrlid Åsa Sjöling Pushpa Saksena Sukanya Raghavan Marianne Quiding-Järbrink 《Cancer immunology, immunotherapy : CII》2014,63(8):807-819
Tumor progression in the colon moves from aberrant crypt foci to adenomatous polyps to invasive carcinomas. The composition of the tumor-infiltrating leukocyte population affects the ability of the immune system to fight the tumor. T cell infiltration into colorectal adenocarcinomas, particularly T helper 1 (Th1) type T cells as well as increased regulatory T cell (Treg) frequencies, is correlated with improved prognosis. However, whether Th1 cells and Tregs are already present at the adenoma stage is not known. In this study, the APCMin/+ mouse model of intestinal adenomatous polyposis was used to investigate tumor-associated lymphocyte subsets and the mechanisms of their accumulation into gastrointestinal adenomas. Compared to unaffected tissue, adenomas accumulated CD4+FoxP3+ putative Treg in parallel with lower frequencies of conventional T cells and B cells. The accumulation of Treg was also observed in human adenomatous polyps. Despite high Treg numbers, the function of conventional T cells present in the APCMin/+ adenomas was not different from those in the unaffected tissue. Adenomas displayed an altered chemokine balance, with higher CCL17 and lower CXCL11 and CCL25 expression than in the unaffected tissue. In parallel, CXCR3+ Tregs were largely absent from adenomas. The data indicate that already in early stages of tumor development, the balance of lymphocyte-recruiting chemokines is altered possibly contributing to the observed shift toward higher frequencies of Treg. 相似文献
64.
Nivedita Roy Supriya Chakraborty Bidisha Paul Chowdhury Sayantan Banerjee Kuntal Halder Saikat Majumder Subrata Majumdar Parimal C. Sen 《PloS one》2014,9(10)
Calcium is an ubiquitous cellular signaling molecule that controls a variety of cellular processes and is strictly maintained in the cellular compartments by the coordination of various Ca2+ pumps and channels. Two such fundamental calcium pumps are plasma membrane calcium ATPase (PMCA) and Sarco/endoplasmic reticulum calcium ATPase (SERCA) which play a pivotal role in maintaining intracellular calcium homeostasis. This intracellular Ca2+ homeostasis is often disturbed by the protozoan parasite Leishmania donovani, the causative organism of visceral leishmaniasis. In the present study we have dileneated the involvement of PMCA4 and SERCA3 during leishmaniasis. We have observed that during leishmaniasis, intracellular Ca2+ concentration was up-regulated and was further controlled by both PMCA4 and SERCA3. Inhibition of these two Ca2+-ATPases resulted in decreased parasite burden within the host macrophages due to enhanced intracellular Ca2+. Contrastingly, on the other hand, activation of PMCA4 was found to enhance the parasite burden. Our findings also highlighted the importance of Ca2+ in the modulation of cytokine balance during leishmaniasis. These results thus cumulatively suggests that these two Ca2+-ATPases play prominent roles during visceral leishmaniasis. 相似文献
65.
Pornpimon Adams Jaranit Kaewkungwal Chanthima Limphattharacharoen Sukanya Prakobtham Krisana Pengsaa Srisin Khusmith 《PloS one》2014,9(11)
Tensions between researchers and ethics committees have been reported in several institutions. Some reports suggest researchers lack confidence in the quality of institutional review board (IRB) reviews, and that emphasis on strict procedural compliance and ethical issues raised by the IRB might unintentionally lead to delays in correspondence between researchers and ethics committees, and/or even encourage prevarication/equivocation, if researchers perceive committee concerns and criticisms unjust. This study systematically analyzed the efficiency of different IRB functions, and the relationship between efficiency and perceived quality of the decision-making process. The major purposes of this study were thus (1) to use the IRB Metrics developed by the Faculty of Tropical Medicine, Mahidol University, Thailand (FTM-EC) to assess the operational efficiency and perceived effectiveness of its ethics committees, and (2) to determine ethical issues that may cause the duration of approval process to be above the target limit of 60 days. Based on a literature review of definitions and methods used and proposed for use, in assessing aspects of IRB quality, an “IRB Metrics” was developed to assess IRB processes using a structure-process-outcome measurement model. To observe trends in the indicators evaluated, data related to all protocols submitted to the two panels of the FTM-EC (clinical and non-clinical), between January 2010–September 2013, were extracted and analyzed. Quantitative information based on IRB Metrics structure-process-outcome illuminates different areas for internal-process improvement. Ethical issues raised with researchers by the IRB, which were associated with the duration of the approval process in protocol review, could be considered root causes of tensions between the parties. The assessment of IRB structure-process-outcome thus provides a valuable opportunity to strengthen relationships and reduce conflicts between IRBs and researchers, with positive outcomes for all parties involved in the conduct of human-subject research. 相似文献
66.
Shailly Anand Sukanya Lal Utkarsh Sood Vipin Gupta Gauri Garg Dhingra Renu Solanki Jasvinder Kaur Roshan Kumar Anjali Saxena Ankita Dua Charu Tripathi Chandni Talwar Charu Dogra Rawat Harpreet Kaur Helianthous Verma Jaspreet Kaur Mansi Verma Mona Singh Princy Hira Nirjara Singhvi Nitish Kumar Mahato Om Prakash Jaya Malhotra Rup Lal Vipin Chandra Kalia 《Indian journal of microbiology》2021,61(4):397
67.
68.
Various optically pure benzocyclobutene and biphenylene-based alpha-amino acid derivatives are prepared in a very high diastereoselective manner via a six step sequence using Sch?llkopfchiral auxiliary. 相似文献
69.
70.
Two forms of biologically active gonadotropin releasing hormones were isolated from the hypothalami ofCatla catla. Gonadotropin releasing hormone activity was studiedin vitro using enzymatically dispersed carp pituitary cell incubation system. Gonadotropin released into the medium was measured by
carp gonadotropin-radio immuno assay. Acetic acid extracted hypothalamic material was subjected to acetone fractionation.
Among the three protein pellets obtained at different time periods (ACI, ACII and ACIII), AC II exhibited the gonadotropin releasing hormone activity. Gel filtration of AC II through Sephadex G-25 column showed
three protein peaks (SG I, SG II SGIII) and only S G II demonstrated strong gonadotropin releasing hormone activity. Elution of SG II through FPLC Mono Q column
(an anion exchanger) in NaCl gradient programme showed one unadsorbed (MQ I) and three adsorbed (MQ II, MQ III and MQ IV)
protein peaks. MQ III, which was eluted with 51% NaCl, exhibited gonadotropin releasing hormone activity. Surprisingly, unadsorbed
fractions, MQ I, also showed gonadotropin releasing hormone activity. MQ 1 was therefore subjected to FPLC Mono S (a cation
exchanger) column chromatography where a highly active gonadotropin releasing hormone enriched peak, i.e., MS III, could be
eluted with 45% NaCl. These findings show thatCatla catla hypothalamus has two forms of gonadotropin releasing hormones one anionic (carp gonadotropin releasing hormone I) and another
cationic (carp gonadotropin releasing hormone II). These two forms of gonadotropin releasing hormones were also active in
heterologous carp species, rohu(Labeo rohita), mrigal(Cirrhinus mrigala) and an exotic common carp(Cyprinus carpio). Combined activity of two forms of gonadotropin releasing hormones was significantly greater as compared to any of the single
form. 相似文献