1,793 research outputs found
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
Prognostic significance of endogenous adhesion/growth-regulatory lectins in lung cancer
Objective: To determine the expression of endogenous adhesion/growth-regulatory lectins and their binding sites using labeled tissue lectins as well as the binding profile of hyaluronic acid as an approach to define new prognostic markers. Methods: Sections of paraffin-embedded histological material of 481 lungs from lung tumor patients following radical lung excision processed by a routine immunohistochemical method (avidin-biotin labeling, DAB chromogen). Specific antibodies against galectins-1 and - 3 and the heparin-binding lectin were tested. Staining by labeled galectins and hyaluronic acid was similarly visualized by a routine protocol. After semiquantitative assessment of staining, the results were compared with the pT and pN stages and the histological type. Survival was calculated by univariate and multivariate methods. Results: Binding of galectin-1 and its expression tended to increase, whereas the parameters for galectin-3 decreased in advanced pT and pN stages at a statistically significant level. The number of positive cases was considerably smaller among the cases with small cell lung cancer than in the group with non-small-cell lung cancer, among which adenocarcinomas figured prominently with the exception of galectin-1 expression. Kaplan-Meier computations revealed that the survival rate of patients with galectin-3-binding or galectin-1-expressing tumors was significantly poorer than that of the negative cases. In the multivariate calculations of survival lymph node metastases ( p < 0.0001), histological type ( p = 0.003), galectin-3-binding capacity ( p = 0.01), galectin-3 expression ( p = 0.03) and pT status ( p = 0.003) proved to be independent prognostic factors, not correlated with the pN stage. Conclusion: The expression and the capacity to bind the adhesion/growth regulatory galectin-3 is defined as an unfavorable prognostic factor not correlated with the pTN stage. Copyright (C) 2005 S. Karger AG, Basel
Synthesis of carbohydrate capped silicon nanoparticles and their reduced cytotoxicity, in vivo toxicity, and cellular uptake
The development of smart targeted nanoparticles (NPs) that can identify and deliver drugs at a sustained rate directly to cancer cells may provide better efficacy and lower toxicity for treating primary and advanced metastatic tumors. Obtaining knowledge of the diseases at the molecular level can facilitate the identification of biological targets. In particular, carbohydrate‐mediated molecular recognitions using nano‐vehicles are likely to increasingly affect cancer treatment methods, opening a new area in biomedical applications. Here, silicon NPs (SiNPs) capped with carbohydrates including galactose, glucose, mannose, and lactose are successfully synthesized from amine terminated SiNPs. The MTT [3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide] analysis shows an extensive reduction in toxicity of SiNPs by functionalizing with carbohydrate moiety both in vitro and in vivo. Cellular uptake is investigated with flow cytometry and confocal fluorescence microscope. The results show the carbohydrate capped SiNPs can be internalized in the cells within 24 h of incubation, and can be taken up more readily by cancer cells than noncancerous cells. Moreover, these results reinforce the use of carbohydrates for the internalization of a variety of similar compounds into cancer cells
Assessing the carcinogenic potential of low-dose exposures to chemical mixtures in the environment: the challenge ahead.
Lifestyle factors are responsible for a considerable portion of cancer incidence worldwide, but credible estimates from the World Health Organization and the International Agency for Research on Cancer (IARC) suggest that the fraction of cancers attributable to toxic environmental exposures is between 7% and 19%. To explore the hypothesis that low-dose exposures to mixtures of chemicals in the environment may be combining to contribute to environmental carcinogenesis, we reviewed 11 hallmark phenotypes of cancer, multiple priority target sites for disruption in each area and prototypical chemical disruptors for all targets, this included dose-response characterizations, evidence of low-dose effects and cross-hallmark effects for all targets and chemicals. In total, 85 examples of chemicals were reviewed for actions on key pathways/mechanisms related to carcinogenesis. Only 15% (13/85) were found to have evidence of a dose-response threshold, whereas 59% (50/85) exerted low-dose effects. No dose-response information was found for the remaining 26% (22/85). Our analysis suggests that the cumulative effects of individual (non-carcinogenic) chemicals acting on different pathways, and a variety of related systems, organs, tissues and cells could plausibly conspire to produce carcinogenic synergies. Additional basic research on carcinogenesis and research focused on low-dose effects of chemical mixtures needs to be rigorously pursued before the merits of this hypothesis can be further advanced. However, the structure of the World Health Organization International Programme on Chemical Safety 'Mode of Action' framework should be revisited as it has inherent weaknesses that are not fully aligned with our current understanding of cancer biology
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
Cancer vaccines: from an immunology perspective
The concept of a therapeutic cancer vaccine to activate anti-tumour immunity pre-dates innovations in checkpoint blockade immunotherapies. However, vaccination strategies have yet to show the hoped-for successes in patients, and unanswered questions regarding the underlying immunological mechanisms behind cancer vaccines have hampered translation to clinical practice. Recent advances in our understanding of the potential of tumour mutational burden and neo-antigen-reactive T cells for response to immunotherapy have re-ignited enthusiasm for cancer vaccination strategies, coupled with the development of novel mRNA-based vaccines following successes in prevention of COVID-19. Here we summarise current developments in cancer vaccines and discuss how advances in our comprehension of the cellular interplay in immunotherapy-responsive tumours may inform better design of therapeutic cancer vaccines, with a focus on the role of dendritic cells as the orchestrators of anti-tumour immunity. The increasing number of clinical trials and research being funnelled into cancer vaccines has demonstrated the ‘proof-of-principle’, supporting the hypothesis that therapeutic vaccines have potential as an immuno-oncology agent. For efficacious and safe cancer vaccines to be developed, better understanding of the underpinning immunological mechanisms is paramount
Cutaneous Neuroimmune Interactions in Peripheral Neuropathic Pain States
Bidirectional interplay between the peripheral immune and nervous systems plays a crucial role in maintaining homeostasis and responding to noxious stimuli. This crosstalk is facilitated by a variety of cytokines, inflammatory mediators and neuropeptides. Dysregulation of this delicate physiological balance is implicated in the pathological mechanisms of various skin disorders and peripheral neuropathies. The skin is a highly complex biological structure within which peripheral sensory nerve terminals and immune cells colocalise. Herein, we provide an overview of the sensory innervation of the skin and immune cells resident to the skin. We discuss modulation of cutaneous immune response by sensory neurons and their mediators (e.g., nociceptor-derived neuropeptides), and sensory neuron regulation by cutaneous immune cells (e.g., nociceptor sensitization by immune-derived mediators). In particular, we discuss recent findings concerning neuroimmune communication in skin infections, psoriasis, allergic contact dermatitis and atopic dermatitis. We then summarize evidence of neuroimmune mechanisms in the skin in the context of peripheral neuropathic pain states, including chemotherapy-induced peripheral neuropathy, diabetic polyneuropathy, post-herpetic neuralgia, HIV-induced neuropathy, as well as entrapment and traumatic neuropathies. Finally, we highlight the future promise of emerging therapies associated with skin neuroimmune crosstalk in neuropathic pain
How speech-language therapists can support secondary school students whose behaviour needs affect their ability to build positive relationships with others, manage self, and engage in learning : a thesis presented in partial fulfilment of the requirements of the degree of Master in Speech Language Therapy, Massey University, Albany, New Zealand
The link between speech, language and communication difficulties and behaviour needs in young people has been widely established within the literature. Young people with behaviour needs at secondary school are likely to have underlying communication difficulties which can contribute to behaviour. However, limited literature exists on speech-language therapists' (SLT) support for young people at secondary school who have behaviour needs. Currently, there is a key focus on early intervention for SLTs working in New Zealand. Limited scope exists for SLTs to work with young people at secondary school, their teachers, and their whānau. The aim of this research study was to understand how SLTs can support the communication skills of young people, aged 13-15, whose behaviour needs affect their ability to build positive relationships with others, manage, self, and engage in learning within a team environment. The research sought to understand: the communication skills and lived experiences of young people with behaviour needs (question one), how the communication skills of the young people could be supported in a team environment (question two), and finally, the team's perspectives and experiences of SLT involvement (question three). Using a case study research design, the researcher worked in a dual role as researcher and Ministry of Education employed SLT. The young people were identified within one secondary school in an Aotearoa New Zealand city. The research project included two teams of participants as the units of analysis. The teams included the young people, their whānau, teachers, and other Ministry of Education professionals. Data were collected through semi-structured interviews, field notes, clinical notes, previous documentation, formal assessments, and checklists. Two global themes arose from question one: Extent of Communication Difficulties and Impact of Communication Difficulties. Question two had two global themes: Challenges and Facilitators. Finally, question three had one global theme: Positive Insights and Steps for the Future. This study provides insight into how SLTs could support young people at secondary school with behaviour needs. The findings have implications for future research and for the wider SLT community to advocate on behalf of the profession and for young people with communication and behaviour needs
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
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