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High-entropy materials (HEMs) are typically crystalline, phase-pure and configurationally disordered materials that contain at least five elements evenly blended into a solid-solution framework. The discovery of high-entropy alloys (HEAs) and high-entropy oxides (HEOs) disrupted traditional notions in materials science, providing avenues for the exploration of new materials, property optimization, and the pursuit of advanced applications. While there has been significant research on HEAs, the creative breakthroughs in HEOs are still being revealed. This focus review aims at developing a structured framework for expressing the concept of HEM, with special emphasis on the crystal structure and functional properties of HEOs. Insights into the recent synthetic advances, that foster prospective outcomes and their current applications in electrocatalysis, and battery, are comprehensively discussed. Further, it sheds light on the existing constraints in HEOs, highlights the adoption of theoretical and experimental tools to tackle challenges, while delineates potential directions for exploration in energy application.
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Host metabolic dysregulation, especially in tryptophan metabolism, is intricately linked to COVID-19 severity and its post-acute sequelae (Long COVID). People living with HIV (PLWH) experience similar metabolic dysregulation and face an increased risk of developing Long COVID. However, whether pre-existing HIV-associated metabolic dysregulations contribute in predisposing PLWH to severe COVID-19 outcomes remains underexplored. Analyzing pre-pandemic samples from PLWH with documented post-infection outcomes, we found specific metabolic alterations, including increased tryptophan catabolism, predicting an elevated risk of severe COVID-19 and the incidence of Long COVID. These alterations warrant further investigation for their potential prognostic and mechanistic significance in determining COVID-19 complications.
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Cyclic transparent optical polymer (CYTOP), a fluoropolymer, finds a plethora of applications in microelectronic devices for sustainable energy harvesting and memory devices. By and large, these devices demand high voltage breakdown, a high dielectric constant, transparency, charge storage, and retention capabilities. Despite many efforts, comprehensive investigation of the charge distribution, retention, and discharge studies conducted on the CYTOP film at the micro-scale remains elusive. Here, we present direct quantification and mapping of surface charge on the CYTOP surface at room temperature using two different modes of advanced surface probe microscopy i.e., Kelvin probe force microscopy (KPFM) and electrostatic force microscopy (EFM). We estimated that the surface charge densities of the CYTOP film using EFM are 1.4 and 3.3 µC/cm2 for the injection of positive and negative charges, respectively. Furthermore, we determined the charge retention time for both injected positive and negative charges. We found that the retention capacity of the negative charges on the CYTOP film is much higher as compared to the positive charges. Moreover, it is also observed that injected negative charges are strongly localized on the CYTOP surface compared to the positive counterpart. Additionally, we demonstrated that charge writing is possible on the CYTOP surface using the AFM conductive tip. These results may find potential applications in energy harvesting, sensing, memory devices, security, and surveillance.
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Background: Betel nut/areca nut/Areca catechu is one of the most commonly used psychoactive substance, and is also a major preventable cause of cancer. Unlike other psychoactive substances, such as nicotine, the mechanisms underlying addiction to areca nuts and related oncogenesis remain elusive. Recent reports suggest a possible overlap in the mechanisms of action of nicotine and areca nuts in the human body. Thus, this study aimed to investigate the interactome of human proteins associated with areca nut exposure and the intricate similarities and differences in the effects of the two psychoactive substances on humans. Methods: A list of proteins associated with areca nut use was obtained from the available literature using terms from Medical Subject Headings (MeSH). Protein-protein interaction (PPI) networks and functional enrichment were analyzed. The results obtained for both psychoactive substances were compared. Results: Given the limited number of common proteins (36/226, 16%) in the two sets, a substantial overlap (612/1176 nodes, 52%) was observed in the PPI networks, as well as in Gene Ontology. Areca nuts mainly affect signaling pathways through three hub proteins (alpha serine/threonine-protein kinase, tumor protein 53, and interleukin-6), which are common to both psychoactive substances, as well as two unique hub proteins (epidermal growth factor receptor and master regulator of cell cycle entry and proliferative metabolism). Areca nut-related proteins are associated with unique pathways, such as extracellular matrix organization, lipid storage, and metabolism, which are not found in nicotine-associated proteins. Conclusions: Areca nuts affect regulatory mechanisms, leading to systemic toxicity and oncogenesis. Areca nuts also affect unique pathways that can be studied as potential markers of exposure, as well as targets for anticancer therapeutic agents.
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The prevalence of polymer usage in everyday activities has emerged as a detriment to both human life and the environment. A large number of studies describe severe impacts of micropolymers (MP) and nanopolymers (NP) on various organ systems, including the endocrine system. Additionally, plasticizers utilized as additives have been identified as endocrine-disrupting chemicals (EDCs). MP/NP, along with associated plasticizers, affect principal signalling pathways of endocrine glands such as the pituitary, thyroid, adrenal, and gonads, thereby disrupting hormone function and metabolic processes crucial for maintaining homeostasis, fertility, neural development, and fetal growth. This review delves into the sources, distribution, and effects of micropolymers, nanopolymers, and associated plasticizers acting as EDCs. Furthermore, it provides a detailed review of the mechanisms underlying endocrine disruption in relation to different types of MP/NP.
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Antimony has a high theoretical capacity and suitable alloying/dealloying potentials to make it a future anode for potassium-ion batteries (PIBs); however, substantial volumetric changes, severe pulverization, and active mass delamination from the Cu foil during potassiation/depotassiation need to be overcome. Herein, we present the use of electrophoretic deposition (EPD) to fabricate binder-free electrodes consisting of Sb nanoparticles (NPs) embedded in interconnected multiwalled carbon nanotubes (MWCNTs). The anode architecture allows volume changes to be accommodated and prevents Sb delamination within the binder-free electrodes. The Sb mass ratio of the Sb/CNT nanocomposites was varied, with the optimized Sb/CNT nanocomposite delivering a high reversible capacity of 341.30 mA h g-1 (â¼90% of the initial charge capacity) after 300 cycles at C/5 and 185.69 mA h g-1 after 300 cycles at 1C. Postcycling investigations reveal that the stable performance is due to the unique Sb/CNT nanocomposite structure, which can be retained over extended cycling, protecting Sb NPs from volume changes and retaining the integrity of the electrode. Our findings not only suggest a facile fabrication method for high-performance alloy-based anodes in PIBs but also encourage the development of alloying-based anodes for next-generation PIBs.
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INTRODUCTION: To assess the placental biometry, placental biomarkers and uterine artery Doppler in each trimester of pregnancy for prediction of early-onset fetal growth restriction (EO FGR). METHODS: In this prospective cohort study placental biometry; biomarkers PAPP-A, sFLT-1, and PlGF along with the uterine artery blood flow evaluation was done serially at 11-14, 20-24 and 28-32 weeks of gestation. The above parameters were compared between women with early onset FGR and controls. RESULTS: Out of 1008 fully followed cases, the small for gestational age fetuses were 227/1008 (22.5 %), and EO FGR were 84/1008(8.3 %).The placental length, volume, and PlGF levels were significantly lower, whereas the uterine artery PI(Ut PI) was significantly higher at all time points among cases. The sFLT-1 level showed a significant increase among cases, whereas it decreased among controls from the first to the second trimester. The detection rate using PV/UtA PI was 60 % in the first trimester and 66.7 % in the second trimester at 30 % FPR. CONCLUSION: The PV/Ut PI in first and the second trimester was a good marker for the prediction of pregnancies at increased risk of developing EO FGR.
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PURPOSE: High densities of tumor infiltrating CD3 and CD8 T-cells are associated with superior prognosis in colorectal cancer (CRC). Their value as predictors of benefit from adjuvant chemotherapy is uncertain. PATIENTS AND METHODS: Tumor tissue from 868 patients in the QUASAR trial (adjuvant fluorouracil/folinic acid v observation in stage II/III CRC) was analyzed by CD3 and CD8 immunohistochemistry. Pathologists, assisted by artificial intelligence, calculated CD3 and CD8 cell densities (cells/mm2) in the core tumor (CT) and invasive margin (IM). Participants were randomly partitioned into training and validation sets. The primary outcome was recurrence-free interval (RFI), 2-year RFI for assessment of biomarker-treatment interactions. Maximum-likelihood methods identified optimal high-risk/low-risk group cutpoints in the training set. Prognostic analyses were repeated in the validation set. RESULTS: In the training set, the recurrence rate in the high-risk group was twice that in the low-risk group for all measures (CD3-CT: rate ratio [RR], 2.00, P = .0008; CD3-IM: 2.38, P < .00001; CD8-CT: 2.17, P = .0001; CD8-IM: 2.13, P = .0001). This was closely replicated in the validation set (RR, 1.96, 1.79, 1.72, 1.72, respectively). In multivariate analyses, prognostic effects were similar in colon and rectal cancers, and in stage II and III disease. Proportional reductions in recurrence with adjuvant chemotherapy were of similar magnitude in the high- and low-recurrence risk groups. Combining information from CD3-IM and CD3-CT (CD3 Score) generated high-, intermediate-, and low-risk groups with numbers needed to treat (NNTs) to prevent one disease recurrence being 11, 21, and 36, respectively. CONCLUSION: Recurrence rates in the high-risk CD3/CD8 groups are twice those in the low-risk groups. Proportional reductions with chemotherapy are similar, allowing NNTs derived in QUASAR to be updated using contemporary, nonrandomized data sets.
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Aim: To assess clinically and histologically the efficacy of TheraCal LC and Biodentine as Direct Pulp Capping agents. Materials and Method: Sixty caries-free maxillary first premolar teeth which were scheduled for orthodontic extraction were selected for the study and were divided equally into Group 1 (Theracal LC) and Group 2 (Biodentine). Thermal and electric pulp testing was performed on the teeth to assess pulp vitality followed by tooth preparation to expose pulp horns under local anesthesia. After achieving hemostasis, the direct pulp capping agent was placed and composite restoration was done. All the teeth were evaluated and compared in terms of clinical and histological findings after 6 weeks. The statistical analysis used was the Kruskal-Wallis test. Results: Teeth with Theracal LC showed no sensitivity to heat, cold, or percussion, whereas sensitivity to heat, cold, or percussion was noted with Biodentine. Histological evaluation revealed that TheraCal LC has higher efficiency in complete dentin bridge formation, had maximum dentin thickness, and showed minimal or no pulpal disorganization and pulpal inflammation as compared to Biodentine. Conclusion: TheraCal LC proves to be a promising future as a direct pulp capping agent.
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BACKGROUND: Multisectoral collaboration is essential for advancing primary health care (PHC). In low- and middle-income countries (LMICs), limited institutional capacities, governance issues, and inadequate stakeholder engagement impede multisectoral collaboration. India faces similar challenges, especially at the meso-level (districts and subdistricts). Owing to its dependence on context, and insufficient evidence, understanding "How" to improve multisectoral collaboration remains challenging. This study aims to elicit specific recommendations to strengthen meso-level stewardship in India for multisectoral collaboration. The findings from this study may offer lessons for other LMICs. METHODS: Using purposive, maximum variation sampling, the study team conducted semi-structured interviews with 20 diverse participants, including policymakers, implementers, development agency representatives, and academics experienced in multisectoral initiatives. The interviews delved into participants' experiences, the current situation, enablers, and recommendations for enhancing stakeholder engagement and capacities at the meso-level for multisectoral collaboration. RESULTS: Context and power are critical elements to consider in fostering effective collaboration. Multisectoral collaboration was particularly successful in three distinct governance contexts: the social-democratic context as in Kerala, the social governance context in Chhattisgarh, and the public health governance context in Tamil Nadu. Adequate health system input and timely guidance instil confidence among local implementers to collaborate. While power plays a role through local leadership's influence in setting agendas, convening stakeholders, and ensuring accountability. To nurture transformative local leaders for collaboration, holistic, equity-driven, community-informed approaches are essential. The study participants proposed several concrete steps: at the state level, establish "central management units" for supervising local implementers and ensuring bottom-up feedback; at the district level, rationalise committees and assign deliverables to stakeholders; and at the block level, expand convergence structures and involve local self-governments. Development partners can support data-driven priority setting, but local implementers with contextual familiarity should develop decentralised plans collaboratively, articulating rationales, activities, and resources. Finally, innovative training programs are required at all levels, fostering humility, motivation, equity awareness, leadership, problem- solving, and data use proficiency. CONCLUSION: This study offers multiple solutions to enhance local implementers' engagement in multisectoral efforts, advocating for the development, piloting, and evaluation of innovative approaches such as the block convergence model, locally-led collaboration efforts, and novel training methods for local implementers.
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Atención Primaria de Salud , Investigación Cualitativa , India , Atención Primaria de Salud/organización & administración , Humanos , Participación de los Interesados , Entrevistas como Asunto , Conducta Cooperativa , Colaboración Intersectorial , Política de SaludRESUMEN
BACKGROUND: District Residency Programme (DRP) was introduced by National Medical Commission as mandatory three-months training program for postgraduate residents. The program was for the first time implemented in April 2023 in Rajasthan. However, it ran into several teething problems, especially for residents. With a lack of any precedence, this study was planned to explore experiences and challenges of residents posted in DRP. METHODS: Cross-sectional study was conducted at 12 DRP sites attached to SMS Medical College, Jaipur between August-October 2023. A self-administered questionnaire was used to collect information from residents who had completed DRP. Questions were scored on a five-point Likert scale. Mann-Whitney U test and Kruskal-Wallis H test was used to show association. RESULTS: Only around 17% residents felt that the learning objectives of DRP were fulfilled and nearly 60% residents felt isolated from academic activities and parent department. Over half of the residents were never posted with their concerned specialty services. Around four-fifth residents felt concerned about safety at least sometimes and more than three-fourth residents were dissatisfied with basic amenities. Kruskal-Wallis and Mann-Whitney tests showed significant association of gender and specialisation strata with multiple outcome variables. CONCLUSION: The study finds high degree of dissatisfaction among residents towards learning objectives, academic learning, and basic amenities during DRP. There was also a clear lack of specialty-exposure and high concerns of safety, especially for female residents. The study findings should alarm and inform policymakers and administrators to improve DRP implementation so as to better achieve laid objectives.
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Internado y Residencia , Humanos , Estudios Transversales , India , Femenino , Masculino , Encuestas y Cuestionarios , Adulto , Educación de Postgrado en Medicina , Actitud del Personal de SaludRESUMEN
BACKGROUND: Resveratrol has demonstrated its ability to regulate BRCA1 gene expression in breast cancer cells, and previous studies have established the binding of MBD proteins to BRCA1 gene promoter regions. However, the molecular mechanism underlying these interactions remains to be elucidated. The aimed to evaluate the impact of MBD proteins on the regulation of BRCA1, BRCA2, and p16 genes and their consequential effects on breast cancer cells. METHODS: Efficacy of resveratrol was assessed using the MTT assay. Binding interactions were investigated through EMSA, ChIP, & MeIP assay. Expression analyses of MBD genes and proteins were conducted using qRT-PCR and western blotting, respectively. Functional assays, including clonogenic, migratory, and sphere formation assays were used to assess cancer cells' colony-forming, metastatic, and tumor-forming abilities. The cytotoxicity of resveratrol on cancer cells was also tested using an apoptosis assay. RESULTS: The study determined an IC50 of 30µM for resveratrol. MBD proteins were found to bind to the BRCA1 gene promoter. Resveratrol exhibited regulatory effects on MBD gene expression, subsequently impacting BRCA1 gene expression and protein levels. Higher concentrations of resveratrol resulted in reduced colony and sphere formation, decreases migration of cancer cells, and an increases number of apoptotic cells in breast cancer cells. Impact Identification of MBD2-BRCA1 axis indicates their significant role in the induction of apoptosis and reduction of metastasis and proliferation in breast cancer cells. Further therapy can be designed to target these MBD proteins and resveratrol could be used along with other anticancer drugs to target breast cancer. CONCLUSIONS: In conclusion MBD2 protein interact to the BRCA1 gene promoter, and resveratrol modulates MBD2 gene expression, which in turn regulates BRCA1 gene expression, and inhibits cell proliferation, migration, and induces apoptosis in ER+, PR+ & Triple negative breast cancer cells.
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Proteína BRCA1 , Proteínas de Unión al ADN , Regulación Neoplásica de la Expresión Génica , Regiones Promotoras Genéticas , Resveratrol , Neoplasias de la Mama Triple Negativas , Resveratrol/farmacología , Resveratrol/uso terapéutico , Humanos , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/metabolismo , Proteínas de Unión al ADN/metabolismo , Proteínas de Unión al ADN/genética , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Receptores de Estrógenos/metabolismo , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/uso terapéuticoRESUMEN
OBJECTIVE: A pregnancy at the utero-tubal junction is a rare type of ectopic pregnancy and is associated with high maternal morbidity if it remains undetected. In the present study we discuss four cases of ectopic pregnancies at the utero-tubal junction which caused diagnostic and management dilemmas. METHODS: Four cases of early pregnancies with the gestational sac (G-sac) implanted near the utero-tubal junction are described. In case 1 this was suspected after a failed attempt at dilatation and curettage at our hospital, cases 2 and 3 presented with amenorrhea and pain abdomen and case 4 was diagnosed on first pregnancy documentation scan after frozen embryo transfer. RESULTS: As initial two-dimensional (2D) transvaginal scan (TVS) failed to diagnose the exact location of the G-sac, three-dimensional (3D) TVS helped to localize the exact location of pregnancy and subsequent individualized management. Case 1 had a partial intramural ectopic pregnancy managed by laparotomy and removal of the ectopic sac. The second and third cases were eccentric uterine pregnancies. The fourth was an interstitial ectopic pregnancy managed by a laparoscopic loop and stitch technique. CONCLUSION: This case series describes the role of 3D TVS for the evaluation of pregnancies implanted at the utero-tubal junction and individual management of eccentric intrauterine, interstitial ectopic and intramural ectopic pregnancies. A diagnostic algorithm for such types of cases and management options is discussed.
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Objective: Using cone beam computed tomography (CBCT), this study compared three rotary file systems-XP Endoshaper, Hyflex CM, and K3 XF-for centering, canal transportation, and root canal area growth. Materials and Methods: The rotating file system randomly separated 60 removed human mandibular molars into three groups (n = 20). Manufacturer-recommended root canal instrumentation was done. Specialized software examined pre- and post-instrumentation CBCT scans. Centering ability was measured by canal transportation and root canal area expansion at different levels from the apex. Results: The Hyflex CM file system had the best centering and the least canal transit at all levels (P < 0.05). XP Endoshaper increased the root canal area the most (P < 0.05). The K3 XF file system had average centering and canal transfer results. Conclusion: The Hyflex CM system centered well, whereas the XP Endoshaper system increased the root canal area the most. The clinical context and therapeutic goals should determine the rotating file system.
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Objectives: Pain is classified as nociceptive, neuropathic, or nociplastic. Neuropathic pain presents as variable phenotypes (characters) based on specific aetiology and pathophysiology. This study aimed to find out among cancer patients the incidence of different phenotypes of neuropathic pain and form specific phenotypic clusters based on the underlying neurophysiology and association of sensory profile with various organ systems - A prospective observational study. Materials and methods: The Institutional Ethical Committee clearance (IEC code: 2020-49-MD-EXP-15) https://ctri.nic.in/Clinicaltrials/showallp.php?mid1=44886&EncHid=88651.15716&userName=CTRI/2020/09/027964 approval was obtained. After written and informed consent, patients of age group 18-80 years, registering in the pain and palliative outpatient department or radiotherapy department with complaints of pain and not taking any anti-neuropathic pain medications, were enrolled. They were assessed using Leeds assessment of neuropathic symptoms and signs (LANSS) pain score, and a score of >12 was eligible for assessment of neuropathic pain phenotypes. Results: Out of 210 cancer patients complaining of pain, a neuropathic component with LANSS >12 was found in 73 (34.76%). The most predominant phenotypes, allodynia> tingling> pricking = burning, were found in 72.60%, 56.16%, and 43.84% of patients, respectively. Phenotypes were clustered into Nodes 1 and 2 based on clinically significant separation of phenotypes. Node 1 had neuropathic pain of spontaneous origin found predominantly in gastrointestinal tract (GIT) and genitourinary tract (GUT) cancers. Node 2 had stimulus-evoked negative and positive characters which occurred in head and neck, thoracic, and spinal metastatic cancers. Conclusion: Careful patient assessment reveals the incidence of neuropathic pain in 34.76%; allodynia and tingling astable the most prominent phenotypes. Broadly, sensory characters were clustered into spontaneous and stimulus-evoked sensations with GIT and GUT cancers presenting with Node 1 symptoms.
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BACKGROUND: Poor intrapartum care in India contributes to high maternal and newborn mortality. India's Labor Room Quality Improvement Initiative (LaQshya) launched in 2017, aims to improve intrapartum care by minimizing complications, enforcing protocols, and promoting respectful maternity care (RMC). However, limited studies pose a challenge to fully examine its potential to assess quality of maternal and newborn care. This study aims to bridge this knowledge gap and reviews LaQshya's ability to assess maternal and newborn care quality. Findings will guide modifications for enhancing LaQshya's effectiveness. METHODS: We reviewed LaQshya's ability to assess the quality of care through a two-step approach: a comprehensive descriptive analysis using document reviews to highlight program attributes, enablers, and challenges affecting LaQshya's quality assessment capability, and a comparison of its measurement parameters with the 352 quality measures outlined in the WHO Standards for Maternal and Newborn Care. Comparing LaQshya with WHO standards offers insights into how its measurement criteria align with global standards for assessing maternity and newborn care quality. RESULTS: LaQshya utilizes several proven catalysts to enhance and measure quality- institutional structures, empirical measures, external validation, certification, and performance incentives for high-quality care. The program also embodies contemporary methods like quality circles, rapid improvement cycles, ongoing facility training, and plan-do-check, and act (PDCA) strategies for sustained quality enhancement. Key drivers of LaQshya's assessment are- leadership, staff mentoring, digital infrastructure and stakeholder engagement from certified facilities. However, governance issues, understaffing, unclear directives, competency gaps, staff reluctance towards new quality improvement approaches inhibit the program, and its capacity to enhance quality of care. LaQshya addresses 76% of WHO's 352 quality measures for maternal and newborn care but lacks comprehensive assessment of crucial elements: harmful labor practices, mistreatment of mothers or newborns, childbirth support, and effective clinical leadership and supervision. CONCLUSION: LaQshya is a powerful model for evaluating quality of care, surpassing other global assessment tools. To achieve its maximum potential, we suggest strengthening district governance structures and offering tailored training programs for RMC and other new quality processes. Furthermore, expanding its quality measurement metrics to effectively assess provider accountability, patient outcomes, rights, staff supervision, and health facility leadership will increase its ability to assess quality improvements.
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Servicios de Salud Materna , Mejoramiento de la Calidad , Femenino , Humanos , Recién Nacido , Embarazo , Madres , Parto , Calidad de la Atención de SaludRESUMEN
Among all non-communicable diseases, Cardiovascular Diseases (CVDs) stand as the leading global cause of mortality. Within this spectrum, Myocardial Infarction (MI) strikingly accounts for over 15 % of all deaths. The intricate web of risk factors for MI, comprising family history, tobacco use, oral health, hypertension, nutritional pattern, and microbial infections, is firmly influenced by the human gut and oral microbiota, their diversity, richness, and dysbiosis, along with their respective metabolites. Host genetic factors, especially allelic variations in signaling and inflammatory markers, greatly affect the progression or severity of the disease. Despite the established significance of the human microbiome-nutrient-metabolite interplay in associations with CVDs, the unexplored terrain of the gut-heart-oral axis has risen as a critical knowledge gap. Moreover, the pivotal role of the microbiome and the complex interplay with host genetics, compounded by age-related changes, emerges as an area of vital importance in the development of MI. In addition, a distinctive disease susceptibility and severity influenced by gender-based or ancestral differences, adds a crucial insights to the association with increased mortality. Here, we aimed to provide an overview on interactions of microbiome (oral and gut) with major risk factors (tobacco use, alcohol consumption, diet, hypertension host genetics, gender, and aging) in the development of MI and therapeutic regulation.
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Microbioma Gastrointestinal , Hipertensión , Microbiota , Infarto del Miocardio , Humanos , Factores de RiesgoRESUMEN
This study endeavors to comprehensively explore and elucidate the seamless integration of NiTi shape memory alloys (SMAs) into multifaceted applications through the utilization of novel joining techniques. The primary focus lies in the utilization of wire arc additive manufacturing (WAAM) to deposit Nitinol (NiTi) onto Copper (Cu), thereby introducing a transformative approach for their integration into electro-mechanical systems and beyond. Through a detailed examination of the NiTi/Cu bimetallic junction, using advanced analytical techniques including SEM, XRD, and DSC analyses, this research aims to unravel the intricate complexities inherent within the interface. The SEM images and X-ray patterns obtained reveal a complex and nuanced interface characterized by a broad mixed zone comprising various constituents, including Ti(Ni,Cu)2, pure Cu, Ti2(Ni,Cu)3 precipitates, and Ni-rich NiTi precipitates. The DSC results, showcasing low-intensity broad peaks during thermal cycling, underscore the inherent challenges in demonstrating functional properties within the NiTi/Cu system. Recognizing the critical importance of an enhanced martensitic transformation, this study delves into the effects of heat treatment. Calorimetric curves post-annealing at 500 °C exhibit distinct transformation peaks, shedding light on the intricate influence of NiTi layer distribution within the junction. The optimal heat treatment parameters for NiTi/Cu junction restoration are meticulously explored and determined at 500 °C for a duration of 12 h. Furthermore, the study offers valuable insights into optimizing NiTi-Cu joints, with micro-hardness values reaching 485 HV and compressive strength scaling up to 650 MPa. These significant findings not only hold promise for diverse applications across various industries but also pave the way for further research directions and explorations into the realm of SMA integration and advanced joining methodologies.
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Androgen deprivation therapy (ADT) is an effective but not curative treatment for advanced and recurrent prostate cancer (PC). We investigated the mechanisms controlling the response to androgen-deprivation by surgical castration in genetically-engineered mouse models (GEMM) of PC, using high frequency ultrasound imaging to rigorously measure tumor volume. Castration initially causes almost all tumors to shrink in volume, but many tumors subsequently recur within 5-10 weeks. Blockade of tumor necrosis factor (TNF) signaling a few days in advance of castration surgery, using a TNFR2 ligand trap, prevents regression in a PTEN-deficient GEMM. Following tumor regression, a basal stem cell-like population within the tumor increases along with TNF protein levels. Tumor cell lines in culture recapitulate these in vivo observations, suggesting that basal stem cells are the source of TNF. When TNF signaling blockade is administered immediately prior to castration, tumors regress but recurrence is prevented, implying that a late wave of TNF secretion within the tumor, which coincides with the expression of NFkB regulated genes, drives recurrence. The inhibition of signaling downstream of one NFkB-regulated protein, chemokine C-C motif ligand 2 (CCL2), prevents post-castration tumor recurrence, phenocopying post-castration (late) TNF signaling blockade. CCL2 was originally identified as a macrophage chemoattractant and indeed at late times after castration gene sets related to chemotaxis and migration are up-regulated. Importantly, enhanced CCL2 signaling during the tumor recurrence phase coincides with an increase in pro-tumorigenic macrophages and a decrease in CD8 T cells, suggesting that recurrence is driven at least in part by tumor immunosuppression. In summary, we demonstrate that a therapy-induced switch in TNF signaling, a consequence of the increased stem cell-like character of the residual tumor cells surviving ADT, induces an immunosuppressive tumor microenvironment and concomitant tumor recurrence.