436 research outputs found
Generation and phenotypic characterization of Pde1a mutant mice
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177029.pdf (publisher's version ) (Open Access)It has been proposed that a reduction in intracellular calcium causes an increase in intracellular cAMP and PKA activity through stimulation of calcium inhibitable adenylyl cyclase 6 and inhibition of phosphodiesterase 1 (PDE1), the main enzymes generating and degrading cAMP in the distal nephron and collecting duct, thus contributing to the development and progression of autosomal dominant polycystic kidney disease (ADPKD). In zebrafish pde1a depletion aggravates and overexpression ameliorates the cystic phenotype. To study the role of PDE1A in a mammalian system, we used a TALEN pair to Pde1a exon 7, targeting the histidine-aspartic acid dipeptide involved in ligating the active site Zn++ ion to generate two Pde1a null mouse lines. Pde1a mutants had a mild renal cystic disease and a urine concentrating defect (associated with upregulation of PDE4 activity and decreased protein kinase A dependent phosphorylation of aquaporin-2) on a wild-type genetic background and aggravated renal cystic disease on a Pkd2WS25/- background. Pde1a mutants additionally had lower aortic blood pressure and increased left ventricular (LV) ejection fraction, without a change in LV mass index, consistent with the high aortic and low cardiac expression of Pde1a in wild-type mice. These results support an important role of PDE1A in the renal pathogenesis of ADPKD and in the regulation of blood pressure
Towards the Design and Evaluation of Clickbait Education Content: Leveraging User Mental Models and Learning Science Principles
Clickbait refers to sensationalized or misleading post on social networking sites (e.g., Facebook) that can trick users into clicking on malicious links. Clickbait is often used in cyberattacks, especially to conduct \u27social engineering attacks\u27 that direct users to malicious websites, resulting in disclosure of users\u27 personal information or installing malicious software (i.e., malware). Thus, clickbait has become a major security concern with the recent boom in social media use. Therefore, security education has become necessary more than ever for the safe and secure use of social media, where there is dearth in security education literature to explore how we could leverage the learning science principles, and the mental models (thought processes about how something works) of users in designing educational contents. We begin to address this gap in our work, where we conducted two online studies over Amazon Mechanical Turk (MTurk), recruiting a total of 834 participants. Our first study aimed to understand the existing mental models of clickbait among social media users; we derived six mental models from our study, which led to the design of security education materials (treatment condition) integrating user mental models with learning science principles. We then conducted our second online study to evaluate treatment condition with the baseline educational content. Our findings denote the efficacy of leveraging user mental models in security education design, and unveil the potentials of integrating learning science principles into the design process. Based on our findings, we provide guidelines for future education research in these directions
Social ecological influences on treatment decision-making in men diagnosed with low risk, localised prostate cancer
Objective: Individuals diagnosed with low risk, localised prostate cancer (PCa) face a difficult decision between active surveillance (AS) and definitive treatment. We aimed to explore perceived influences on treatment decision-making from the patient and partner\u27s perspectives. Methods: Patients (and partners) who met AS criteria and had chosen their treatment were recruited. Semi-structured individual interviews were conducted via telephone to explore experiences of diagnosis, impact on patient lifestyle, experiences with physicians, treatment preferences/choice, treatment information understanding and needs, and overall decision-making process. Interviews were audio recorded, transcribed verbatim, and analysed using Reflexive Thematic Analysis. Results: Twenty-four male patients (18 chose AS) and 12 female partners participated. Five themes relating to social-ecological influences on treatment choice were identified: (1) partner support and direct influence on patient treatment choice, (2) patient and partner vicarious experiences may influence treatment decisions, (3) the influence of the patient\u27s life circumstances, (4) disclosing to wider social networks: friends, family, and co-workers, and (5) the importance of a good relationship and experience with physicians. Additionally, two themes were identified relating to information patients and partners received about the treatment options during their decision-making process. Conclusions: A range of individual and social influences on treatment decision-making were reported. Physicians providing treatment recommendations should consider and discuss the patient and partner\u27s existing beliefs and treatment preferences and encourage shared decision-making. Further research on treatment decision-making of partnered and non-partnered PCa patients is required. We recommend research considers social ecological factors across the personal, interpersonal, community, and policy levels
Improved connectivity and cognition due to cognitive stimulation in Alzheimer’s disease
BackgroundDue to the increasing prevalence of Alzheimer’s disease (AD) and the limited efficacy of pharmacological treatment, the interest in non-pharmacological interventions, e.g., cognitive stimulation therapy (CST), to improve cognitive dysfunction and the quality of life of AD patients are on a steady rise.ObjectivesHere, we examined the efficacy of a CST program specifically conceptualized for AD dementia patients and the neural mechanisms underlying cognitive or behavioral benefits of CST.MethodsUsing neuropsychological tests and MRI-based measurements of functional connectivity, we examined the (neuro-) psychological status and network changes at two time points: pre vs. post-stimulation (8 to 12 weeks) in the intervention group (n = 15) who received the CST versus a no-intervention control group (n = 15).ResultsAfter CST, we observed significant improvement in the Mini-Mental State Examination (MMSE), the Alzheimer’s Disease Assessment Scale, cognitive subsection (ADAS-cog), and the behavioral and psychological symptoms of dementia (BPSD) scores. These cognitive improvements were associated with an up-regulated functional connectivity between the left posterior hippocampus and the trunk of the left postcentral gyrus.ConclusionOur data indicate that CST seems to induce short-term global cognition and behavior improvements in mild to moderate AD dementia and enhances resting-state functional connectivity in learning- and memory-associated brain regions. These convergent results prove that even in mild to moderate dementia AD, neuroplasticity can be harnessed to alleviate cognitive impairment with CST
Lymphatic Malformations of the Orbit
ObjectivesLymphatic malformations of the orbit are rare lesions that constitute approximately 1% to 8% of all orbital masses. They are difficult to treat since they do not remain within anatomic boundaries and tend to penetrate into normal orbital structures. The aim was to analyze clinical courses and therapy options in patients with lymphatic malformations of the orbit.MethodsThirteen patients with orbital lymphatic malformations confirmed by magnetic resonance imaging between 1998 and 2009 were enrolled in this study. Patients' charts were retrospectively reviewed to analyze clinical courses and treatment options.ResultsFour patients suffered from isolated intraorbital lymphatic malformations without conjunctival involvement, in three of them the masses were completely resected, in one patient close controls were performed. Three patients had isolated intraorbital lymphatic malformations with conjunctival involvement. Surgical volume reduction of the exterior parts of the lymphatic malformation were performed without any complications and satisfying outcome in these cases. Six patients suffered from intra- and periorbital lymphatic malformations. In 3 patients a watch-and-wait strategy was initiated. In the other 3 patients a surgical therapy was performed, one patient additionally received sclerotherapy with OK-432; however, these 3 patients suffered from residual lymphatic malformations.ConclusionThe presented cases underline the inconsistencies in the malformations behavior and underscore the inability to make specific recommendations regarding treatment. The treatment decision should be based on the size and location of the lymphatic malformation. The untreated patient must be watched for signs of visual detoriation, which may signal the need for therapeutic intervention
Cardiogenic Induction of Pluripotent Stem Cells Streamlined Through a Conserved SDF-1/VEGF/BMP2 Integrated Network
BACKGROUND: Pluripotent stem cells produce tissue-specific lineages through programmed acquisition of sequential gene expression patterns that function as a blueprint for organ formation. As embryonic stem cells respond concomitantly to diverse signaling pathways during differentiation, extraction of a pro-cardiogenic network would offer a roadmap to streamline cardiac progenitor output. METHODS AND RESULTS: To resolve gene ontology priorities within precursor transcriptomes, cardiogenic subpopulations were here generated according to either growth factor guidance or stage-specific biomarker sorting. Innate expression profiles were independently delineated through unbiased systems biology mapping, and cross-referenced to filter transcriptional noise unmasking a conserved progenitor motif (55 up- and 233 down-regulated genes). The streamlined pool of 288 genes organized into a core biological network that prioritized the "Cardiovascular Development" function. Recursive in silico deconvolution of the cardiogenic neighborhood and associated canonical signaling pathways identified a combination of integrated axes, CXCR4/SDF-1, Flk-1/VEGF and BMP2r/BMP2, predicted to synchronize cardiac specification. In vitro targeting of the resolved triad in embryoid bodies accelerated expression of Nkx2.5, Mef2C and cardiac-MHC, enhanced beating activity, and augmented cardiogenic yield. CONCLUSIONS: Transcriptome-wide dissection of a conserved progenitor profile thus revealed functional highways that coordinate cardiogenic maturation from a pluripotent ground state. Validating the bioinformatics algorithm established a strategy to rationally modulate cell fate, and optimize stem cell-derived cardiogenesis
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A digital, decentralized trial of exercise therapy in patients with cancer
We developed and evaluated the Digital Platform for Exercise (DPEx): a decentralized, patient-centric approach designed to enhance all aspects of clinical investigation of exercise therapy. DPEx integrated provision of a treadmill with telemedicine and remote biospecimen collection permitting all study procedures to be conducted in patient's homes. Linked health biodevices enabled high-resolution monitoring of lifestyle and physiological response. Here we describe the rationale and development of DPEx as well as feasibility evaluation in three different cohorts of patients with cancer: a phase 0a development study among three women with post-treatment primary breast cancer; a phase 0b proof-of-concept trial of neoadjuvant exercise therapy in 13 patients with untreated solid tumors; and a phase 1a level-finding trial of neoadjuvant exercise therapy in 53 men with localized prostate cancer. Collectively, our study demonstrates the utility of a fully digital, decentralized approach to conduct clinical trials of exercise therapy in a clinical population
Intramyocardial Transplantation of Undifferentiated Rat Induced Pluripotent Stem Cells Causes Tumorigenesis in the Heart
BACKGROUND: Induced pluripotent stem cells (iPSCs) are a novel candidate for use in cardiac stem cell therapy. However, their intrinsic tumorigenicity requires further investigation prior to use in a clinical setting. In this study we investigated whether undifferentiated iPSCs are tumorigenic after intramyocardial transplantation into immunocompetent allogeneic recipients. METHODOLOGY/PRINCIPAL FINDINGS: We transplanted 2 × 10(4), 2 × 10(5), or 2 × 10(6) cells from the established rat iPSC line M13 intramyocardially into intact or infarcted hearts of immunocompetent allogeneic rats. Transplant duration was 2, 4, or 6 weeks. Histological examination with hematoxylin-eosin staining confirmed that undifferentiated rat iPSCs could generate heterogeneous tumors in both intracardiac and extracardiac sites. Furthermore, tumor incidence was independent of cell dose, transplant duration, and the presence or absence of myocardial infarction. CONCLUSIONS/SIGNIFICANCE: Our study demonstrates that allogeneic iPSC transplantation in the heart will likely result in in situ tumorigenesis, and that cells leaked from the beating heart are a potential source of tumor spread, underscoring the importance of evaluating the safety of future iPSC therapy for cardiac disease
Hematopoietic Stem Cell Transplantation for C1q Deficiency: A Study on Behalf of the EBMT Inborn Errors Working Party
\ua9 The Author(s) 2024. C1q deficiency is a rare inborn error of immunity characterized by increased susceptibility to infections and autoimmune manifestations mimicking SLE, with an associated morbidity and mortality. Because C1q is synthesized by monocytes, to date, four patients treated with allogeneic HSCT have been reported, with a positive outcome in three. We conducted an international retrospective study to assess the outcome of HSCT in C1q deficiency. Eighteen patients, fourteen previously unreported, from eleven referral centres, were included. Two patients had two HSCTs, thus 20 HSCTs were performed in total, at a median age of 10 years (range 0.9—19). Indications for HSCT were autoimmune manifestations not controlled by ongoing treatment in seventeen, and early development of MALT lymphoma in one patient. Overall survival (OS) was 71% and event-free survival was 59% at two years (considering an event as acute GvHD ≥ grade III, disease recurrence and death). In eleven patients HSCT led to resolution of autoimmune features and discontinuation of immunosuppressive treatments (follow-up time range 3–84 months). Five patients died due to transplant-related complications. Patients with a severe autoimmune phenotype, defined as neurological and/or renal involvement, had the worst OS (40% vs 84%; p = 0.034). Reviewing data of 69 genetically confirmed C1q deficient patients, we found that anti-Ro antibodies are associated with neurologic involvement, and anti-RNP and anti-DNA antibodies with renal involvement. In conclusion, HSCT may be a valid curative option for C1q deficiency, but careful selection of patients, with an accurate assessment of risk and benefit, is mandatory
Stem Cell Therapy: Pieces of the Puzzle
Acute ischemic injury and chronic cardiomyopathies can cause irreversible loss of cardiac tissue leading to heart failure. Cellular therapy offers a new paradigm for treatment of heart disease. Stem cell therapies in animal models show that transplantation of various cell preparations improves ventricular function after injury. The first clinical trials in patients produced some encouraging results, despite limited evidence for the long-term survival of transplanted cells. Ongoing research at the bench and the bedside aims to compare sources of donor cells, test methods of cell delivery, improve myocardial homing, bolster cell survival, and promote cardiomyocyte differentiation. This article reviews progress toward these goals
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