Long term Ultra-Violet Variability of Seyfert galaxies

Flux variability is one of the defining characteristics of Seyfert galaxies, a class of active galactic nuclei (AGN). Though these variations are observed over a wide range of wavelengths, results on their flux variability characteristics in the ultra-violet (UV) band are very limited. We present here the long term UV flux variability characteristics of a sample of fourteen Seyfert galaxies using data from the International Ultraviolet Explorer acquired between 1978 and 1995. We found that all the sources showed flux variations with no statistically significant difference in the amplitude of UV flux variation between shorter and longer wavelengths. Also, the flux variations between different near-UV (NUV, 1850 - 3300 A) and far-UV (FUV, 1150 - 2000 A) passbands in the rest frames of the objects are correlated with no time lag. The data show indications of (i) a mild negative correlation of UV variability with bolometric luminosity and (ii) weak positive correlation between UV variability and black hole mass. At FUV, about 50% of the sources show a strong correlation between spectral indices and flux variations with a hardening when brightening behaviour, while for the remaining sources the correlation is moderate. In NUV, the sources do show a harder when brighter trend, however, the correlation is either weak or moderate.Comment: Accepted by Journal of Astrophysics and Astronom

Rip/singularity free cosmology models with bulk viscosity

In this paper we present two concrete models of non-perfect fluid with bulk viscosity to interpret the observed cosmic accelerating expansion phenomena, avoiding the introduction of exotic dark energy. The first model we inspect has a viscosity of the form ${\zeta} = {\zeta}_0 + ({\zeta}_1-{\zeta}_2q)H$ by taking into account of the decelerating parameter q, and the other model is of the form ${\zeta} = {\zeta}_0 + {\zeta}_1H + {\zeta}_2H^2$. We give out the exact solutions of such models and further constrain them with the latest Union2 data as well as the currently observed Hubble-parameter dataset (OHD), then we discuss the fate of universe evolution in these models, which confronts neither future singularity nor little/pseudo rip. From the resulting curves by best fittings we find a much more flexible evolution processing due to the presence of viscosity while being consistent with the observational data in the region of data fitting. With the bulk viscosity considered, a more realistic universe scenario is characterized comparable with the {\Lambda}CDM model but without introducing the mysterious dark energy.Comment: 9 pages, 6 figures, submitted to EPJ-

A study of the knowledge, attitude and behavior among patients with psoriasis vulgaris during the COVID-19 lockdown period

Background: Patients with psoriasis may have been directly impacted by the COVID-19 lockdown and this may have had a significant effect on disease severity and treatment compliance. This study aims to investigate the knowledge, attitude and the behavioral practices of patients with psoriasis during the lockdown period.Methods: A self-assessed questionnaire was employed for the purpose of this study and was answered by 100 patients of clinically diagnosed psoriasis.Results: Although several patients were aware of their condition and its implications, a significant number of responders were found to have a faulty treatment compliance due to the COVID-19 lockdown.Conclusions: To our knowledge, this is the first study that evaluates the knowledge, attitude and behaviour during the COVID-19 lockdown period of individuals who have been clinically diagnosed with psoriasis. This study raises the possibility that the sustained psychosocial stress induced by the current pandemic can potentially lead to exacerbations or onset of common inflammatory skin conditions like psoriasis. The overall compliance to dermatologic therapy was slightly poor as there were frequent concerns regarding the safety of visiting a hospital or a doctor as well as possible financial constraints. As per this study, there is an urgent need to convey the right information about managing psoriasis during the COVID-19 pandemic among both the general population and patients alike.

Effect of Rabbit Epididymal Antimicrobial Peptide, REHbβP, on LPS-Induced Proinflammatory Cytokine Responses in Human Vaginal Cells In Vitro

Antimicrobial peptides (AMP's) protect epithelial surfaces including epididymis against pathogens and play a key role in orchestrating various defensive responses. Recently, we have identified one such AMP, rabbit epididymal hemoglobin-β subuit (REHbβP) from the epididymal fluid of rabbit, Oryctologus cuniculus. The demonstration of a protective role of REHbβP in epididymal epithelial cells (EPEC's) led us to investigate: (1) the identification of LPS interactive domain in REHbβP, and (2) whether the REHbβP of rabbit origin mediates vaginal cellular immune responses of another species (human). HeLa-S3, human vaginal epithelial cells (hVECs) were exposed to LPS or the LPS-stimulated cells treated with REHbβP or neutral peptide, nREHbβP. Effect of LPS and cytokines (IL-6 and IL-1α) and chemokines (IL-8, MCP-1) levels was determined in the culture supernatants. In response to the LPS, hVECs synthesized these mediators and the levels were significantly higher than controls. This enhancing effect was ameliorated when the LPS-induced hVECs were treated with REHbβP. Similar results were obtained on NF-κB protein and hBD-1 mRNA expression. Confocal microscopy studies revealed that REHbβP attenuated the LPS-induced internalization of E. coli by macrophages. The chemotaxis studies performed using Boyden chamber Transwell assay, which showed elevated migration of U937 cells when the supernatants of LPS-induced hVECs were used, and the effect was inhibited by REHbβP. REHbβP was found to be localized on the acrosome of rabbit spermatozoa, suggesting its role in sperm protection beside sperm function. In conclusion, REHbβP may have the potential to develop as a therapeutic agent for reproductive tract infections (RTI's)

Geodesic Deviation in Regge Calculus

Geodesic deviation is the most basic manifestation of the influence of gravitational fields on matter. We investigate geodesic deviation within the framework of Regge calculus, and compare the results with the continuous formulation of general relativity on two different levels. We show that the continuum and simplicial descriptions coincide when the cumulative effect of the Regge contributions over an infinitesimal element of area is considered. This comparison provides a quantitative relation between the curvature of the continuous description and the deficit angles of Regge calculus. The results presented might also be of help in developing generic ways of including matter terms in the Regge equations.Comment: 9 pages. Latex 2e with 5 EPS figures. Submitted to CQ

EHD2 Promotes Store-Operated Calcium Entry (SOCE) and Cellular Migration in Ovarian Cancer Cells

Ovarian cancer (OC) ranks as the 5th most common cause of cancer deaths of women, reflecting late diagnoses and lack of targeted therapies. EHD2, a member of the Eps15 homology (EH) domain containing (EHD) proteins family, regulates cell surface expression of Orai1, the mediator of store-operated calcium entry (SOCE) in breast cancer. Disrupting the EHD2-Orai1 axis in OC could provide novel targeted therapies against metastatic disease.https://digitalcommons.unmc.edu/surp2023/1002/thumbnail.jp

Study on the reproductive behavior among women of rural areas of Pondicherry

Background: The fertility rate in India is declining and it is necessary to know the factors responsible for such decline in different states. It was decided to study reproductive behavior of women contributing to decline in fertility in Pondicherry. The aim and objective of this study is known the reproductive behavior of women in the rural areas on Pondicherry.Methods: Sample of 300 married women aged between 30 and 60 years were selected randomly from village belonging to Katerikuppam PHC and the data collected using the pre tested semi open ended questionnaires by interviewing the subjects at their doorsteps during September to November 2014.Results: The mean age of the subjects was 41.5 ± 9.5 years. There were 793 total pregnancies and live births were 701 and abortions accounted for ten percent and still births were 9 in number. The mean number of pregnancies and live births were 2.6 ± 1.1 and 2.3 ± 1.0 per women respectively. The mean age at menarche, marriage and first pregnancy were 14.3 ± 1.4, 19.6 ± 3.1 and 21.1 ± 3.1 years respectively. The mean number of pregnancies were declined from currently older age to the lower age of the subjects and found to be statistically significant.Conclusions: The mean age at marriage and first pregnancy is increasing and the differences in the mean number of pregnancies and live births are showing declining trend.

Comparative Immunohistochemical Analysis of EHD1 Expression in Adjacent, Metastatic, and Normal Thyroid Tissue

The discovery of prognostic biomarkers plays a crucial role in enhancing the treatment and care of individuals with differentiated thyroid cancer (DTC) who are at risk of disease progression. A significant breakthrough came with earlier research, which revealed higher levels of the EHD1 protein in papillary DTC when compared to the surrounding healthy tissue. This exciting finding served as the driving force behind the initiation of a more extensive investigation aimed at validating EHD1 as a potential biomarker and exploring its connection with clinical outcomes. By unraveling the potential implications of EHD1 in DTC cases, this study holds the promise of advancing our understanding and approach to managing this type of cancer effectively.https://digitalcommons.unmc.edu/surp2023/1001/thumbnail.jp

EHD1 is Required for IGF-1R-mediated Oncogenic Signaling in Ewing Sarcoma

Background and Significance: Ewing Sarcoma (EWS) is the second most common malignant bone tumor of children and adolescents. Patients with metastatic or recurrent disease have very poor outcomes. The receptor tyrosine kinase(RTK) insulin-like-growth-factor-1-receptor (IGF-1R) is upregulated in 93% of EWS patients with anti-IGF-1R antibodies and kinase inhibitors in clinical studies. However, with only ~10% of patients achieving objective responses, delineation of novel pathways that facilitate IGF-1R-driven oncogenesis in EWS could provide avenues for more effective therapy. The RTK levels and compartmentalization at the cell surface determine their access to growth factors, thus dictating the downstream oncogenic signaling. Our lab has demonstrated that EPS15-homology-domain-containing-protein-1 (EHD1) regulates traffic of cell surface receptors, including RTKs. We observed high frequency (67%) of EHD1 overexpression in 266 primary EWS patient tumor tissues, and Kaplan-Meier survival analysis of publicly available mRNA expression data showed that high EHD1 expression was associated with shorter patient survival. Objective/Question: This study aims to comprehend the underlying role of EHD1 in EWS oncogenesis. Experimental design and Results: In both dox-inducible EHD1-shRNA knockdown and EHD1-CRISPR-Cas9-knockout (KO) EWS cell line models(TC71, A673, and SKES1), we observed a significant impairment of in vitro oncogenic properties namely, cell proliferation, migration, invasion, soft-agar colony formation, and tumor-sphere formation, and the phenotypes were restored upon mouse-EHD1 rescue. Furthermore, by orthotopically implanting TC71 cells in the tibia of nude mice(xenograft model), we demonstrated a significant reduction in tumor size upon EHD1-depletion. Using a phospho-RTK profiling antibody array, we found reduced phospho-IGF-1R levels upon EHD1-KD, identifying IGF-1R as a potential target of regulation by EHD1. EHD1-KO reduced surface IGF-1R levels under steady-state and ligand-free conditions in EWS cells. IGF-1R and EHD1 were also found to colocalize intracellularly and co-immunoprecipitate after IGF-1 stimulation. Notably, EHD1-KO impaired the IGF-1R-mediated activation of downstream AKT and MAPK pathways. Mechanistically, EHD1 was shown to regulate traffic of newly synthesized IGF-1R and recycled pools from the Golgi to the cell surface, and in absence of EHD1, intracellular IGF-1R was shunted to the lysosome resulting in degradation. Finally, by dual targeting of EHD1 (genetic depletion) and IGF-1R (small-molecule-inhibitor Linsitinib), we observed an additive effect on inhibition of EWS cell proliferation and migration and upregulation of apoptosis. Conclusions: Our studies indicate a novel regulatory pathway of EHD1 requirement in IGF-1R cell surface display and sustaining IGF-1R-mediated oncogenesis in EWS. This highlights the prospects of therapeutic co-targeting of EHD1 and IGF-1R, thus enhancing IGF-1R targeted therapies in EWS.https://digitalcommons.unmc.edu/chri_forum/1040/thumbnail.jp