Cellular homeostasis, implantation window and unexplained infertility: role of phosphatase and tensin homolog deleted on chromosome 10

Background: Balance between endometrial cell proliferation and apoptosis is crucial for successful embryo implantation. PTEN (phosphatase and tensin homolog deleted on chromosome 10), a pro-apoptotic factor, is proposed to be one of the signaling proteins through which estrogen and progesterone act to affect cellular homeostasis. Although reports in literature have suggested role of PTEN in regulating endometrial cell proliferation and apoptosis during window of implantation, its involvement in women with unexplained infertility is not clear. In the present study, we examined expression, cellular distribution and activation status of PTEN, cell proliferation, and apoptosis in midsecretory endometrium from women with unexplained infertility as compared to fertile controls.Methods: Endometrial biopsies from infertile (n=11) and fertile women (n=22) were used for immunohistochemical evaluation of PTEN, phospho-PTEN and Ki67. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labeling assay was performed for detection of apoptotic cells.Results: Biopsies from infertile women as compared to fertile controls demonstrated statistically significant: i) decrease in nuclear PTEN (P < 0.001), increase in nuclear phospho-PTEN (P < 0.05), increase in nuclear and cytoplasmic phospho-PTEN/PTEN ratio (P < 0.001 and P < 0.05 respectively) in endometrial stroma, ii) increase in cytoplasmic phospho-PTEN (P < 0.001) and phospho-PTEN/PTEN ratio (P < 0.05) in glandular epithelium (GE), iii) increase in Ki67 labeling in GE (P < 0.01) and stroma (P < 0.05) and, iv) decrease in (P < 0.001) apoptosis.Conclusions: Altered PTEN expression and associated modulation in cellular homeostasis during the implantation window might contribute to mechanism underlying unexplained infertility

Covalent Binding Antibodies Suppress Advanced Glycation: On the Innate Tier of Adaptive Immunity

Non-enzymatic protein glycation is a source of metabolic stress that contributes to cytotoxicity and tissue damage. Hyperglycemia has been linked to elevation of advanced glycation endproducts, which mediate much of the vascular pathology leading to diabetic complications. Enhanced glycation of immunoglobulins and their accelerated vascular clearance is proposed as a natural mechanism to intercept alternative advanced glycation endproducts, thereby mitigating microvascular disease. We reported that antibodies against the glycoprotein KLH have elevated reactivity for glycopeptides from diabetic serum. These reactions are mediated by covalent binding between antibody light chains and carbonyl groups of glycated peptides. Diabetic animals that were immunized to induce reactive antibodies had attenuated diabetic nephropathy, which correlated with reduced levels of circulating and kidney-bound glycation products. Molecular analysis of antibody glycation revealed the preferential modification of light chains bearing germline-encoded lambda V regions. We previously noted that antibody fragments carrying V regions in the germline configuration are selected from a human Fv library by covalent binding to a reactive organophosphorus ester. These Fv fragments were specifically modified at light chain V region residues, which map to the combining site at the interface between light and heavy chains. These findings suggest that covalent binding is an innate property of antibodies, which may be encoded in the genome for specific physiological purposes. This hypothesis is discussed in context with current knowledge of the natural antibodies that recognize altered self molecules and the catalytic autoantibodies found in autoimmune disease

Practical approach to management of respiratory complications in neurological disorders

Patients with certain neurological diseases are at increased risk of developing chest infections as well as respiratory failure due to muscular weakness. In particular, patients with certain neuromuscular disorders are at higher risk. These conditions are often associated with sleep disordered breathing. It is important to identify patients at risk of respiratory complications early in the course of their disease, although patients with neuromuscular disorders often present in the acute setting with respiratory involvement. This review of the respiratory complications of neurological disorders, with a particular focus on neuromuscular disorders, explores why this happens and looks at how to recognize, investigate, and manage these patients effectively

Obesity and respiratory diseases

The obesity epidemic is a global problem, which is set to increase over time. However, the effects of obesity on the respiratory system are often underappreciated. In this review, we will discuss the mechanical effects of obesity on lung physiology and the function of adipose tissue as an endocrine organ producing systemic inflammation and effecting central respiratory control. Obesity plays a key role in the development of obstructive sleep apnea and obesity hypoventilation syndrome. Asthma is more common and often harder to treat in the obese population, and in this study, we review the effects of obesity on airway inflammation and respiratory mechanics. We also discuss the compounding effects of obesity on chronic obstructive pulmonary disease (COPD) and the paradoxical interaction of body mass index and COPD severity. Many practical challenges exist in caring for obese patients, and we highlight the complications faced by patients undergoing surgical procedures, especially given the increased use of bariatric surgery. Ultimately, a greater understanding of the effects of obesity on the respiratory disease and the provision of adequate health care resources is vital in order to care for this increasingly important patient population

Expression and cellular distribution of insulin-like growth factor 1 receptor during window of implantation in infertile women with intramural fibroids

Background: The “window of implantation” (WOI) is a transient but well defined period during which the hostile endometrial lining is transformed to a surface receptive to accept the embryo. Recently, data are beginning to accumulate suggesting negative influence of non-cavity distorting intramural uterine fibroids (NCD-IMF) on endometrial receptivity that may have implications for implantation failure. However, molecular mechanisms underlying infertility associated with NCD-IMF remain unclear. The aim of present study was to examine the expression and cellular distribution of insulin-like growth factor 1 receptor (IGF1R) during WOI in infertile women with NCD-IMF and fertile controls. While, reports are available that support role of IGF1R in mediating adhesive interaction with the implanting blastocyst, the effect of NCD-IMF on IGF1R expression during the WOI is not defined.Methods: Quantitative real-time polymerase chain reaction and immunohistochemistry were used to evaluate messenger RNA (mRNA) and protein expression of IGF1R in midsecretory endometrial biopsies obtained from infertile women with NCD-IMF (n=20) and healthy fertile controls (n=10).Results: As compared to fertile controls, significantly higher IGF1R: i) mRNA levels (1.59 fold up regulation; p=0.044) and ii) immunoscore in the luminal epithelium (8.94±3.13 versus 6.31±1.49; p=0.009) were observed in infertile women with NCD-IMF.Conclusions: Over expression of IGF1R in infertile women with NCD-IMF, during the window of receptivity, may result in altered ability of uterine epithelial cells for blastocyst adhesion and subsequent implantation, which might lead to poor reproductive outcome in these women

Determinism of Stochastic Processes through the Relationship between the Heat Equation and Random Walks

We study the deterministic characteristics of stochastic processes through investigation of random walks and the heat equation. The relationship is confirmed by discretizing the heat equation in time and space and determining the probability distribution function for random walks in dimension d = 1, 2. The existence of the relationship is presented both through theoretical analysis and numerical computation

Rad6B acts downstream of Wnt signaling to stabilize β-catenin: Implications for a novel Wnt/β-catenin target

Abstract Background Aberrant Wnt/β-catenin signaling is associated with breast cancer even though genetic mutations in Wnt signaling components are rare. We have previously demonstrated that Rad6B, an ubiquitin conjugating enzyme, stabilizes β-catenin via polyubiqutin modifications that render β-catenin insensitive to proteasomal degradation. Rad6B is a transcriptional target of β-catenin, creating a positive feedback loop between Rad6B expression and β-catenin activation. Methods To isolate subpopulations expressing high or low Rad6B levels, we transfected MDA-MB-231 or WS-15 human breast cancer cells with ZsGreen fluorescent reporter vector in which the expression of ZsGreen was placed under the control of Rad6B promoter. ZsGreenhigh and ZsGreenlow subpopulations, reflective of high and low Rad6B promoter activity, respectively, were isolated by FACS. To determine the relevance of Wnt signaling in Rad6B-mediated β-catenin stabilization/activation, the ZsGreenhigh cells were transfected with signaling-defective Wnt coreceptor LRP6Δ173. Rad6B expression and promoter activity were determined by RT-PCR, Western blot and Rad6B promoter-mediated luciferase assays. β-catenin levels and transcriptional activity were determined by Western blot and TOP/FOP Flash reporter assays. Tumor formation and morphologies of ZsGreenlow, ZsGreenhigh, and ZsGreenhigh/LRP6Δ173 cells compared to unsorted vector controls were evaluated in nude mice. Expression of Wnt signaling related genes was profiled using the Wnt signaling pathway RT2 Profiler PCR arrays. Results ZsGreenhigh subpopulations showed high Rad6B expression and Rad6B promoter activity as compared to ZsGreenlow cells. ZsGreenhigh (high Rad6B expressors) also showed elevated β-catenin levels and TOP/Flash activity. Inhibiting Wnt signaling in the high Rad6B expressors decreased ZsGreen fluorescence, Rad6B gene expression, β-catenin levels and TOP/Flash activity. Tumors derived from high Rad6B expressors were predominantly composed of cells with epithelial mesenchymal transition (EMT) phenotype as compared to control tumors that were composed of both cuboidal and EMT-type cells. Tumors derived from low Rad6B expressors lacked EMT phenotype. Inhibition of LRP6 function in the high Rad6B expressors abrogated the EMT phenotype. Gene expression profiling showed upregulation of several Wnt signaling pathway regulators in high Rad6B expressors that were downregulated by interference of Wnt signaling with mutant LRP6 or by Rad6B silencing. Conclusions These data reveal a functional link between the canonical Wnt pathway and Rad6B in β-catenin activation and breast cancer progression

A Communal Retreat for Writers in the Adirondacks

This thesis will explore the design of a retreat for writers in Adirondack Park in upper New York State. The intent of the project is to investigate how the 'border' between a group of buildings and the natural wooded landscape in which they sit may be blurred. It is the assumption of the author that rendering indistinct this border between the built and the natural will have bearing on whether a human's relationship to nature is harmonious. This study considers the transition (space, plane, or volume) from built to natural material: how do a compound, a building, and a construction detail meet the natural world in a manner in which the distinction between natural and human built is unconventionally blurred? How do a collection of buildings, a structure, and a detail suggest a harmonious relationship with the natural setting in which, or with which, they sit? The purpose of this thesis is to explore these questions and thus investigate the transition of natural landscape to built work at a variety of scales: the site scale, the building scale, and the detail scale