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Kavitha Sivasubramaiyan Swapnil Totey Vijay Bhat Satish M Totey Kaushik Deb 《Journal of biomedical science》2009,16(1):88-9
Trophoblast differentiation and formation of the placenta are important events linked to post-implantation embryonic development.
Models mimicking the biology of trophoblast differentiation in a post-implantation maternal microenvironment are needed for
understanding disorders like placental-ischemia or for applications in drug-screening, and would help in overcoming the ethical
impasse on using human embryos for such research. Here we attempt to create such a model by using embryoid bodies (EBs) and
a biomimetic platform composed of a bilayer of fibronectin and gelatin on top of low-melting agarose. Using this model we
test the hypothesis that cystic-EBs (day 30) that resemble blastocysts morphologically, are better sources as compared to
noncytic EBs (day 10), for functional trophoblast differentiation; and that the Rho kinases inhibitor Y27632 can enhance this
differentiation. Non/cytic EBs with/out Y27632 were grown on this platform for 28 days, and screened from secretion and expression
of trophoblast and other lineage markers using ECLIA, RT-PCR, and Immunofluorescence. All EBs attached on this surface and
rapidly proliferated into hCG and progesterone (P2) secreting functional trophoblast cells. However, the cells derived from
cytic-EBs and cytic-EBs+ Y27632 showed the maximum secretion of these hormones and expressed IGF2, supporting our hypothesis.
Also Y27632 reduced extraembryonic endoderm and trophoblast lineage differentiation from early noncystic-EBs, whereas, it
specifically enhanced the induction of trophoblast and multinucleated syncitiotrophoblast differentiation from late cystic-EBs.
In vivo trophoblast differentiation can be replicated in fibronectin based biomaterials, using cytic-EBs and by maneuvering the Rho-ROCK
pathways. Response of EBs to a compound may vary temporally, and determination of their right stage is crucial for applications
in directed-differentiation or drug-screening. 相似文献
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S. Chandrappa C.V. Kavitha M.S. Shahabuddin K. Vinaya C.S. Ananda Kumar S.R. Ranganatha Sathees C. Raghavan K.S. Rangappa 《Bioorganic & medicinal chemistry》2009,17(6):2576-2584
In order to explore the anticancer effect associated with the thiazolidinone framework, several 2-(5-((5-(4-chlorophenyl)furan-2-yl)methylene)-4-oxo-2-thioxothiazolidin-3-yl)acetic acid derivatives 5(a–l) were synthesized. Variation in the functional group at C-terminal of the thiazolidinone led to set of compounds bearing amide moiety. Their chemical structures were confirmed by 1H NMR, IR and Mass Spectra analysis. These thiazolidinone compounds containing furan moiety exhibits moderate to strong antiproliferative activity in a cell cycle stage-dependent and dose dependent manner in two different human leukemia cell lines. The importance of the electron donating groups on thiazolidinone moiety was confirmed by MTT and Trypan blue assays and it was concluded that the 4th position of the substituted aryl ring plays a dominant role for its anticancer property. Among the synthesized compounds, 5e and 5f have shown potent anticancer activity on both the cell lines tested. To rationalize the role of electron donating group in the induction of cytotoxicity we have chosen two molecules (5e and 5k) having different electron donating group at different positions. LDH assay, Flow cytometric analysis and DNA fragmentation suggest that 5e is more cytotoxic and able to induce the apoptosis. 相似文献
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Kumaresan A Bujarbaruah KM Kadirvel G Khargharia G Sarma RG Goswami J Basumatary R Palaniappan K Bardoloi RK 《Theriogenology》2011,75(4):687-695
The present study reports the age related changes in the peripheral testosterone levels, testicular and epididymal growth and development and cauda epididymal spermiogram in local pigs of Northeastern India, which attain sexual maturity around 3 months of age. Local boars (n = 20) were castrated at monthly intervals from 2 to 6 months of age (4 boars per month) to study the testicular growth and development and the epididymal spermiogram. Blood samples, collected from local boars (n = 6) at monthly intervals from 2 to 6 months of age, were analyzed for testosterone levels by radioimmunoassay. Compared to Hampshire boars, significantly (P < 0.05) high testosterone levels were observed in the local boars as early as 2 months of age. The mean (± SEM) level of testosterone in the local boars at 2, 3 and 4 months of age was 11.89 ± 1.52, 20.45 ± 1.33 and 20.38 ± 2.0 ngml−1, respectively. Though there was consistently significant (P < 0.05) difference in the body weight between Hampshire and local pigs, the same was not observed in case of testicular weight except at 3 and 6 months of age. In line with the above observation, the testis:body weight ratio (gram testis per kg body weight) was significantly (P < 0.05) higher in the local boars compared to the Hampshire boars at any time of observation, which ranged from 0.8 to 1.0 in case of Hampshire and from 2.3 to 3.0 in local boars. The sperm concentration in the cauda epididymal fluid of local boars at 2, 3 and 6 months of age was 2255 ± 186.6, 3685 ± 103.8 and 4325 ± 146.2 million/ml, respectively and the sperm motility, viability and total abnormality was 73.3, 75.2 and 6.2%, respectively at 3 months of age. Taken together, the testosterone level, testicular growth and development and epididymal spermiogram indicate the trait of early sexual maturity in the local pigs as compared to Hampshire. 相似文献
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Varicella-zoster virus (VZV) reactivation causes herpes zoster, which is accompanied by an influx of lymphocytes into affected ganglia, but the stimulus for this infiltrate is not known. We report that VZV infection of ganglia leads to increased CXCL10 production in vitro, in an explant ganglion model and in naturally infected dorsal root ganglia (DRG) during herpes zoster. Lymphocytes expressing the receptor for CXCL10, CXCR3, were also observed throughout naturally infected ganglia during herpes zoster, including immediately adjacent to neurons. This study identifies VZV-induced CXCL10 as a potential driver of T lymphocyte recruitment into DRG during herpes zoster. 相似文献
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A wide variety of mammalian cell types is used in gene transfection studies. Establishing transfection methods that enable highly efficient DNA uptake has become increasingly important. PC12 is an established rat pheochromocytoma cell line, which responds to exposure to NGF with cessation of growth, expression of cytoplasmic processes, and differentiation into cells resembling sympathetic neurons. Although PC12 cells represent an important model system to study a variety of neuronal functions, they proved relatively difficult to transfect. We have compared the efficiency of three different chemical transfection reagents (Lipofectamine 2000, Lipofectamine LTX and TransIT-LT1) and of two electroporation systems (Neon and Gene Pulser Xcell) in transiently transfecting undifferentiated PC12 cells. By comparing efficiencies from replicate experiments we proved electroporation (in particular Neon) to be the method of choice. By optimizing different parameters (voltage, pulse width and number of pulses) we reached high efficiency of transfection (90 %) and viability (99 %). We also demonstrated that, upon electroporation, cells are not altered by the transfection and maintain their ability to differentiate. 相似文献
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In Oryza sativa (rice) there are seven members in the NRAMP (natural resistance- associated macrophage protein) family of transporter proteins. They have been identified as OsNRAMP1, OsNRAMP2, OsNRAMP3, OsNRAMP4, OsNRAMP5, OsNRAMP6 and OsNRAMP7. Several metal ions like Zn2+, Mn2+, Fe2+, Cd2+ etc. have been studied to be transported via NRAMP transporter proteins in rice plant. In spite of this, very little information is available regarding these transporters. Hence it is important to computationally predict and characterize the OsNRAMP family of transporters for studying and understanding their molecular insights in future studies. For this purpose, various in silico methods and tools were used for the characterization of OsNRAMP family of transporter proteins. Physico-chemical properties of the protein sequences were calculated, putative transmembrane domains (TMDs) and conserved motif signatures were determined and their interaction partners were predicted. 3D models of all the members of OsNRAMP transporters were generated using online structure prediction tool followed by their analysis. In silico microarray analysis was done to understand the expression pattern of these transporters in rice plant. Currently, only limited knowledge is available about the structural and functional aspects of these transporters, hence this study would provide more theoretical information about them. 相似文献
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Manalee Vishnu Surve Anjali Anil Kshama Ganesh Kamath Smita Bhutda Lakshmi Kavitha Sthanam Arpan Pradhan Rohit Srivastava Bhakti Basu Suryendu Dutta Shamik Sen Deepak Modi Anirban Banerjee 《PLoS pathogens》2016,12(9)
Infection of the genitourinary tract with Group B Streptococcus (GBS), an opportunistic gram positive pathogen, is associated with premature rupture of amniotic membrane and preterm birth. In this work, we demonstrate that GBS produces membrane vesicles (MVs) in a serotype independent manner. These MVs are loaded with virulence factors including extracellular matrix degrading proteases and pore forming toxins. Mice chorio-decidual membranes challenged with MVs ex vivo resulted in extensive collagen degradation leading to loss of stiffness and mechanical weakening. MVs when instilled vaginally are capable of anterograde transport in mouse reproductive tract. Intra-amniotic injections of GBS MVs in mice led to upregulation of pro-inflammatory cytokines and inflammation mimicking features of chorio-amnionitis; it also led to apoptosis in the chorio-decidual tissue. Instillation of MVs in the amniotic sac also resulted in intrauterine fetal death and preterm delivery. Our findings suggest that GBS MVs can independently orchestrate events at the feto-maternal interface causing chorio-amnionitis and membrane damage leading to preterm birth or fetal death. 相似文献