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111.
Kalajzic I Staal A Yang WP Wu Y Johnson SE Feyen JH Krueger W Maye P Yu F Zhao Y Kuo L Gupta RR Achenie LE Wang HW Shin DG Rowe DW 《The Journal of biological chemistry》2005,280(26):24618-24626
The inherent heterogeneity of bone cells complicates the interpretation of microarray studies designed to identify genes highly associated with osteoblast differentiation. To overcome this problem, we have utilized Col1a1 promoter-green fluorescent protein transgenic mouse lines to isolate bone cells at distinct stages of osteoprogenitor maturation. Comparison of gene expression patterns from unsorted or isolated sorted bone cell populations at days 7 and 17 of calvarial cultures revealed an increased specificity regarding which genes are selectively expressed in a subset of bone cell types during differentiation. Furthermore, distinctly different patterns of gene expression associated with major signaling pathways (Igf1, Bmp, and Wnt) were observed at different levels of maturation. Some of our data differ from current models of osteoprogenitor cell differentiation and emphasize components of the pathways that were not revealed in studies based on a total cell population. Thus, applying methods to generate more homogeneous populations of cells at a defined level of cellular differentiation from a primary osteogenic culture is feasible and leads to a novel interpretation of the gene expression associated with increasing levels of osteoprogenitor maturation. 相似文献
112.
The PCR-based genome walking method has been commonly used to isolate upstream regions from known cDNA sequences. The limitation of this technique is based on the location of the restriction site upstream to the gene-specific primer in the genome; hence, different restriction enzymes have to be used to isolate larger upstream fragments. In this paper, we present the advantageous use of partial and size-selected DNA as templates for genome walking, in isolating larger upstream fragments. We have successfully tested this approach to isolate larger upstream fragments using the FailSafe PCR System. Use of partial digestion and size selection can provide better chances in obtaining larger flanking regions of known DNA sequence, when compared to use of total digested DNA. 相似文献
113.
Salmonella faces a variety of stresses including acid and heat, in the natural environment whether in the gastrointestinal tract of mammalian host or in the external environment during transmission where survival and multiplication is a priority for the pathogen. In the present study, Salmonella enterica serovar Typhi was grown under acid (inorganic and organic) as well as heat stress and the outermembrane protein (OMP) profiles were compared. A 55 kDa OMP was found to be expressed with high intensity under the selected stress conditions in comparison to normal conditions. The protein expressed under acidic stress reacted with antibodies raised against heat shock protein indicating the similarity of atleast some of the epitopes. In vivo immunogenicity (reactivity with typhoid patient sera) revealed that the 55kDa protein under each stress condition was reactive with 83% of the typhoid sera. In the light of role of the stress induced proteins in pathogenesis of microbial infections and their immunogenic potential, these findings may be relevant for a better understanding of the host-microbe interactions and for future development of diagnostic and preventive strategies. 相似文献
114.
Ameena Jehaludi E. Kevin Heist M. Russell Giveans Rishi Anand 《Indian pacing and electrophysiology journal》2018,18(3):100-107
Background
Although a rare complication of catheter based ablation for atrial fibrillation (AF), atrioesophageal fistula (AEF) is a serious and fatal event [[1], [2], [3], [4], [5]]. Most reports of AEF are single cases or small case series.Objective
The purpose of this study was to perform a comprehensive literature search of all published atrioesophageal fistula following catheter ablation for AF in order to identify the mortality rates associated with therapeutic modalities and suggest the most definitive management in reducing mortality.Methods
A comprehensive literature review of reported observational cases of atrioesophageal fistula post catheter based ablation for atrial fibrillation was performed.Results
Sixty-five cases of AEF post atrial fibrillation ablation were reviewed. The mean age was 55 years old. 73.8% (48/65) of the identified cases occurred in males (p?<?0.001). Of the 65 cases, 13 underwent surgical radiofrequency ablation (RFA) and 52 underwent percutaneous RFA. Mortality resulted in 53.8% of those who underwent surgical RFA and in 55.8% of those who underwent percutaneous RFA (p?=?.888). The time range interval from procedure to onset of symptoms was 1–60 days. The most prevalent symptom, fever, occurred in 52 of the 65 cases, followed by neurological symptoms (n?=?44). CT of the chest (n?=?37), transthoracic echocardiogram (n?=?21), and CT of the head (n?=?18) were the preferred diagnostic modalities. Patients who underwent surgical correction with esophageal repair for treatment were more likely to survive, in comparison to patients who were treated with non-surgical interventions, such as antibiotic therapy, anticoagulation therapy or esophageal stenting. Of the total 34 patients who were treated surgically, 27 survived (79.4%). Of the total 31 patients who were treated non-surgically, only 2 survived (6.5%), reflecting significantly lower mortality with surgical versus non-surgical therapy (p?<?0.001).Conclusion
Atrioesophageal fistula is an uncommon but potentially fatal complication of atrial fibrillation ablation. Patients who underwent surgical repair were twelve times more likely to survive than those treated with stenting, antibiotic therapy or no intervention. Based on the observation that patients are 12 times more likely to survive an AEF with surgery than without, the authors believe that prompt surgical correction of AEF should be considered as standard of care when dealing with this dreaded complication. 相似文献115.
116.
Bahman Tabaraie Bal Krishan Sharma Praveen Rishi nee Sharma Rakesh Sehgal Nirmal Kumar Ganguly 《Microbiology and immunology》1994,38(7):561-565
Porins were prepared from smooth strain of Salmonella typhi 0–901 and chemotype rough mutant of S. typhimurium Ra-30. Porins could significantly stimulate the immune systems of mice. Immunization of mice with the porins provoked synthesis of anti-porin antibodies. Macrophages from the immunized mice showed increased capacity to generate oxygen free radicals, and lymphocytes from these mice showed proliferative response to the porins. Thus porins may play a role in providing protection from salmonellosis by stimulating the antibody production and increasing the capacity of macrophages to generate oxygen free radicals along with stimulation of lymphocytes. 相似文献
117.
118.
Rishi Rikhi Elizabeth M. Wilson Olivier Deas Matthew N. Svalina John Bial Atiya Mansoor Stefano Cairo Charles Keller 《Biochemistry and Biophysics Reports》2016
Background and aimsBreast cancer is the most common cancer in women and the second leading cause of cancer-related deaths in this population. Breast cancer related deaths have declined due to screening and adjuvant therapies, yet a driving clinical need exists to better understand the cause of the deadliest aspect of breast cancer, metastatic disease. Breast cancer metastasizes to several distant organs, the liver being the third most common site. To date, very few murine models of hepatic breast cancer exist.MethodsIn this study, a novel murine model of liver breast cancer using the MDA-MB-231 cell line is introduced as an experimental (preclinical) model.ResultsHistological typing revealed consistent hepatic breast cancer tumor foci. Common features of the murine model were vascular invasion, lung metastasis and peritoneal seeding.ConclusionsThe novel murine model of hepatic breast cancer established in this study provides a tool to be used to investigate mechanisms of hepatic metastasis and to test potential therapeutic interventions. 相似文献
119.
Rishi Raj Sharmistha Mitra Balasubramanian Gopal 《Biochemical and biophysical research communications》2018,495(2):2078-2084
Polynucleotide phosphorylase catalyzes both 3′-5′ exoribonuclease and polyadenylation reactions. The crystal structure of Staphylococcus epidermidis PNPase revealed a bound phosphate in the PH2 domain of each protomer coordinated by three adjacent serine residues. Mutational analysis suggests that phosphate coordination by these serine residues is essential to maintain the catalytic center in an active conformation. We note that PNPase forms a complex with RNase J1 and RNase J2 without substantially altering either exo-ribonuclease or polyadenylation activity of this enzyme. This decoupling of catalytic activity from protein-protein interactions suggests that association of these endo- or exo-ribonucleases with PNPase could be more relevant for cellular localization or concerted targeting of structured RNA for recycling. 相似文献
120.
The present study describes the status of somatostatin receptors (SSTRs) and their colocalization with insulin (β), glucagon (α) and somatostatin (δ) producing cells in the pancreatic islets of 11 weeks old R6/2 Huntington's Disease transgenic (HD tg) and age-matched wild type (wt) mice. We also determined expression of tyrosine hydroxylase (TH), glutamic acid decarboxylase (GAD) and presynaptic marker synaptophysin (SYP) in addition to signal transduction pathways associated with diabetes. In R6/2 mice, islets are relatively smaller in size, exhibit enhanced expression and nuclear inclusion of mHtt along with the loss of insulin, glucagon and somatostatin expression. In comparison to wt, R6/2 mice display enhanced mRNA for all SSTRs except SSTR2. In the pancreatic lysate, SSTR1, 4 and 5 immunoreactivity decreases whereas SSTR3 immunoreactivity increases with no discernible changes in SSTR2 immunoreactivity. Furthermore, at the cellular level, R6/2 mice exhibit a receptor specific distributional pattern of SSTRs like immunoreactivity and colocalization with β, α and δ cells. While GAD expression is increased, TH and SYP immunoreactivity was decreased in R6/2 mice, anticipating a cross-talk between the CNS and pancreas in diabetes pathophysiology. We also dissected out the changes in signaling pathway and found decreased activation and expression of PKA, AKT, ERK1/2 and STAT3 in R6/2 mice pancreas. These findings suggest that the impaired organization of SSTRs within islets may lead to perturbed hormonal regulation and signaling. These interconnected complex events might shed new light on the pathogenesis of diabetes in neurodegenerative diseases and the role of SSTRs in potential therapeutic intervention. 相似文献