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Perception of quality of life for cats and dogs of low-income Spanish and English-speaking veterinary clients attending problem focused or routine veterinary visits is an important area of focus for community based veterinary service providers. Using a qualitative approach, 50 New York City based American Society for the Prevention of Cruelty to Animals (ASPCA) veterinary clients completed semi-structured interviews as well as a survey about their perception of life with their pets. Veterinary clients shared both human-animal bond (HAB) related and quality of life (QoL) related factors in their daily experience of life with their pets. Results indicated that this demographic perceives QoL similarly to previous QoL research that either does not report sample demographics or reports sample demographics with more affluence. Moreover, 60% of qualitative excerpts included both HAB and QoL themes and 40% were discretely HAB or QoL. An analog single item 10-point scale measuring veterinary client perception of their pets QoL did not differentiate between sample demographics at a statistically significant level. Finally, pet QoL literature has not traditionally reflected diverse demographic identities of veterinary clients or widely included reliable and valid measures of the human-animal bond (HAB). These results support the importance of measuring the HAB when researching pet QoL and provide evidence that lower-income Spanish and English-speaking veterinary clients are similarly bonded and attentive to their pets as other demographics.
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BACKGROUND: It has been suggested that a 30-50â¯% lithium dose reduction or lithium discontinuation 24-48â¯h before delivery could minimize neonatal complications. We investigated the maternal lithemia changes around delivery after a brief discontinuation, the placental transfer of lithium at delivery, and the association between neonatal lithemia at delivery and acute neonatal outcomes. METHODS: A retrospective observational cohort study was conducted in a teaching hospital (November/2006-December/2018). Data was extracted from the medical records. We included psychopathologically stable women, with a singleton pregnancy, treated with lithium in late pregnancy, with at least one maternal and neonatal lithemia at delivery. Lithium was discontinued 12â¯h before a scheduled caesarean section or induction, or at admission day to hospital birth; and restarted 6-12â¯h post. RESULTS: Sixty-six mother-infant pairs were included, and 226 maternal and 66 neonatal lithemias were obtained. We found slight maternal lithemia fluctuations close to 0.20â¯mEq/L, and early postpartum relapse of 6â¯%. The mean (SD) umbilical cord/mother intrapartum lithemia ratio was 1.10 (0.17). Fifty-six percent of neonates presented transient acute complications. Neonatal hypotonia was the most frequent outcome (Nâ¯=â¯15). Mean lithemia were 0.178â¯mEq/L higher in those with hypotonia than in those without (pâ¯=â¯0.028). LIMITATIONS: It is a retrospective cohort of a moderate sample size of healthy uncomplicated pregnancies and results cannot be generalized to all pregnant treated with lithium. CONCLUSIONS: Lithium transfers completely across the placenta. A brief predelivery lithium discontinuation was associated with slight maternal lithemia fluctuations. Neonates exposed intrautero to lithium present frequent but transient acute effects.
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BACKGROUND: Lipocalin-2 (LCN-2) is an osteokine that suppresses appetite, stimulates insulin secretion, regulates bone remodeling, and is induced by proinflammatory cytokines. The aim of this work was to investigate the participation of LCN-2 in periodontitis associated with type 2 diabetes (T2D) by evaluating alveolar bone loss, glycemic control, inflammation, and femur fragility. METHODS: A murine model of periodontitis with T2D and elevated LCN-2 concentration was used. Functional LCN-2 inhibition was achieved using an anti-LCN-2 polyclonal antibody, and isotype immunoglobulin G was used as a control. The alveolar bone and femur were evaluated by micro-CT. Glucose metabolism was determined. Tumor necrosis factor (TNF-α) and receptor activator of nuclear factor kappa-B ligand (RANKL) levels in alveolar bone lysates were quantified using ELISA, and serum cytokines were quantified using flow cytometry. A three-point bending test was performed in the femur, and RANKL levels were measured in femur lysates using ELISA. RESULTS: Functional inhibition of LCN-2 in T2D-periodontitis mice decreased alveolar bone loss in buccal and palatal surfaces and preserved the microarchitecture of the remaining bone, decreased TNF-α and RANKL in alveolar bone, reduced hyperglycemia, glucose intolerance, and insulin resistance, and increased insulin production through improving the functionality of pancreatic ß cells. Furthermore, this inhibition increased serum free-glycerol levels, decreased serum interleukin (IL)-6, increased serum IL-4, and reduced femur fragility and RANKL expression in the femur. CONCLUSIONS: LCN-2 participates in periodontitis associated with T2D. Inhibiting its function in mice with T2D and periodontitis improves pancreatic ß-cell function, and glucose metabolism and decreases inflammatory cytokines and bone-RANKL levels, which results in the preservation of femoral and alveolar bone microarchitecture. PLAIN LANGUAGE SUMMARY: In this study, we explored the role of a bone protein known as lipocalin-2 (LCN-2) in the connection between periodontitis and type 2 diabetes (T2D). Periodontitis is a destructive gum and alveolar bone disease. LCN-2 levels are increased in both T2D and periodontitis. Using a mouse model of T2D with periodontitis, we examined how blocking LCN-2 function affected various aspects of these two diseases. We found that this inhibition led to significant improvements. First, it reduced alveolar bone loss and preserved bone structure by decreasing local inflammation and bone resorption. Second, it improved glucose and lipid metabolism, leading to better blood-sugar control and decreased insulin resistance. Blocking the functions of LCN-2 also decreased systemic inflammation throughout the body and strengthened bone integrity. Overall, our results suggest that LCN-2 plays a crucial role in the periodontitis associated with T2D. By inhibiting LCN-2 function, we were able to improve pancreatic function, improve glucose metabolism, reduce inflammation, and enhance bone health. Targeting LCN-2 could be a promising strategy for the harmful effects of T2D and periodontitis.
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Plants face numerous environmental stresses that hinder their growth and productivity, including biotic agents, such as herbivores and parasitic microorganisms, as well as abiotic factors, such as cold, drought, salinity, and high temperature. To counter these challenges, plants have developed a range of defense strategies. Among these, plant antimicrobial proteins and peptides (APPs) have emerged as a promising solution. Due to their broad-spectrum activity, structural stability, and diverse mechanisms of action, APPs serve as powerful tools to complement and enhance conventional agricultural methods, significantly boosting plant defense and productivity. This review focuses on different studies on APPs, emphasizing their crucial role in combating plant pathogens and enhancing plant resilience against both biotic and abiotic stresses. Beginning with in vitro studies, we explore how APPs combat various plant pathogens. We then delve into the defense mechanisms triggered by APPs against biotic stress, showcasing their effectiveness against bacterial and fungal diseases. Additionally, we highlight the role of APPs in mitigating the abiotic challenges associated with climatic change. Finally, we discuss the current applications of APPs in agriculture, emphasizing their potential for sustainable agricultural practices and the need for future research in this area.
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Nanoplastics pollution has led to a severe environmental crisis because of a large accumulation of these smaller nanoplastic particles in the aquatic environment and atmospheric conditions. Detection of these nanoplastics is crucial for food safety monitoring and human health. In this work, we report a simple and eco-friendly method to prepare a SERS-substrate-based nanoporous Ag nanoparticle (NP) film through vacuum thermal evaporation onto a vacuum-compatible deep eutectic solvent (DES) coated growth substrate for quantitative detection of nanoplastics in environmental samples. The nanoporous Ag NP films with controlled pores were achieved by the soft-templating role of DESs over the growth substrate, which enabled the self-assembly of deposited Ag NPs over the surface of DES. The optimized nanoporous Ag substrate provides high sensitivity in the detection of analyte molecules, crystal violet (CV), and rhodamine 6G (R6G) with a limit of detection (LOD) up to 1.5 × 10-13 M, excellent signal reproducibility, and storage stability. Moreover, we analyzed quantitative SERS detection of polyethene terephthalate (PET, size of 200 nm) and polystyrene (PS, size of 100 nm) nanoplastics with an LOD of 0.38 and 0.98 µg/mL, respectively. In addition, the SERS substrate efficiently detects PET and PS nanoplastics in real environmental samples, such as tap water, lake water, and diluted milk. The enhanced SERS sensing ability of the proposed nanoporous Ag NP film substrate holds immense potential for the sensitive detection of various nanoplastic contaminants present in environmental water.
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INTRODUCTION: Breast cancer (BC) and its treatment can impair patient quality of life (QoL), and those undergoing more aggressive treatments may be more severely impacted. Objective: Assess the level of perception of the QoL of patients treated for BC at the Hospital de Clínicas and the Departmental Hospital of Soriano. MATERIALS AND METHODS: A questionnaire for cancer patients (EORTC, QLQ-C30) and one specific for BC (EORTC QLQ-BR23) were used. RESULTS: A total of 158 patients who had completed chemotherapy treatment at least one year prior to the evaluation were enrolled. The average age was 61 years old. QLQC QUESTIONNAIRE: The global QoL score (GQOL) was high: 70.9. Patients undergoing breast-conservation surgery (BCS) had better scores in physical and emotional functioning (p < 0.005) and presented less frequently with: pain, constipation, and financial difficulties (p < 0.005). Those undergoing sentinel lymph node biopsy (SLNB) had higher scores for GQOL and for physical, role, and social functioning scales (p < 0.001) and had less fatigue, pain, insomnia, and financial difficulties (p < 0.005). QUESTIONNAIRE QLQBR: Sexual functioning and sexual enjoyment scales were relatively low. Patients undergoing BCS had better scores on the functional scales: body image and future outlook; and fewer breast symptoms (p < 0.005). Those undergoing SLNB also had better scores on the functional scales for body image and future outlook future and presented less frequently with symptoms (p < 0.005). CONCLUSION: Uruguayan BC patients experience high values on the GQOL scale; those undergoing BCS and SLNB had better scores on most functional and problem/symptom scales. Patients undergoing BCS had better scores in physical and emotional functioning and presented less frequently with pain, constipation, and financial difficulties. With respect to the type of axillary surgery received, patients who underwent SLNB had higher scores on the GQOL scale and on the physical, role, and social functional scales. The implementation of intervention strategies aimed at improving the quality of life, and the physical and emotional care of patients is recommended.
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Neoplasias de la Mama , Calidad de Vida , Humanos , Femenino , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/terapia , Neoplasias de la Mama/psicología , Neoplasias de la Mama/patología , Persona de Mediana Edad , Encuestas y Cuestionarios , Anciano , Uruguay/epidemiología , Radioterapia Adyuvante/métodos , Radioterapia Adyuvante/estadística & datos numéricos , Adulto , Quimioterapia Adyuvante/métodos , Biopsia del Ganglio Linfático Centinela , Mastectomía , Mastectomía Segmentaria/psicología , Terapia CombinadaRESUMEN
Introduction: Large and Giant intracranial aneurysms (LGIAs) have become the paradigm for which endovascular techniques do not provide satisfactory results. Yet, microsurgery is followed by non-negligible rates of morbimortality. This scenario may have changed since the introduction of flow-diversion devices. Research question: Contemporary and standardised revision on microsurgical and endovascular results, with emphasis on anterior circulation LGIAs. Materials and methods: A systematic literature search was conducted in two databases (PubMed and Embase) on treatment outcomes of LGIAs of the anterior circulation, after the introduction of flow-diverters 2008/01/01, till 2023/05/20. Small case series (<5 cases), series including >15% of posterior circulation aneurysms, and studies not reporting clinical and/or angiographic outcomes were excluded. Results: 44 relevant studies (observational cohorts) were identified, including 2923 LGIAs predominantly from anterior circulation. Mean follow-up 22 (±20) months. 1494 (51%) LGIAs were treated endovascularly and 1427 (49%) microsurgically. According to the random effects model, pooled rates of favourable clinical outcomes were 85.8% (CI 95% 82.6-88.4), complete occlusion 69.4% (CI 95% 63.7-7.46), complications 19.6% (CI 95%16-23.9) and mortality 5.6% (CI 95% 4.4-7.1). Focusing on type of treatment, occlusion rates are higher with microsurgical (842/993, 85% vs 874/1,299, 67%), although good outcomes are slightly more frequent with endovascular (1045/1,135, 92% vs 1120/1,294, 87%). Discussion and conclusions: According to contemporary data about occlusion rates, functional outcomes, and complications, primary or secondary treatment of LGIAs of the anterior circulation seems justified. Microsurgical occlusion rates are higher in LGIAs. An expert consensus on reporting complications and management strategies is warranted.
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BACKGROUND: Variation in human left bundle branch (LBB) anatomy has a significant effect on the sequence of left ventricular depolarization. However, little is known regarding the electrophysiological characteristics of pacing different LBB fascicles. OBJECTIVE: We aimed to analyse the different electrocardiographic characteristics of LBB pacing (LBBP) attending to the site of pacing at the LBB system. METHODS: In 200 consecutive patients with confirmed LBBP, we distinguished left bundle trunk capture (LBTP) from any LB fascicular pacing (LBFP) based on the presence of LB potentials and paced QRS morphologies. We compared them regarding procedure, LBBP criteria and electrical synchrony parameters. RESULTS: One hundred and seventy-three patients with LBFP were compared to 25 patients with LBTP. Left septal and posterior fascicles were significantly more prevalent than left anterior in LBFP (46.8 %, 41.0 % and 12.2 % respectively). QRS transition criteria (80.0 % vs 61.8 %; p = 0.077), selective LBBP (40.0 vs 21.5 %; p = 0.101), paced QRS width (110.3 ± 16.8 ms vs 115.4 ± 14.9 ms; p = 0.117), V6-RWPT (79.2 ± 10.7 ms vs 75.3 ± 9.7 ms; p = 0.068) and interpeak interval (42.5 ± 19.1 ms vs 45.7 ± 12.9 ms; p = 0.282) were not significantly different between LBTP and LBFP. All short-term complications occurred in LBFP, mainly driven by septal perforations (n = 23), without any difference in the pacing parameters. Among the LBFP subgroups, only aVL-RWPT was longer when the posterior fascicle was paced. CONCLUSIONS: LBFP is much more prevalent than LBTP in unselected consecutive patients with LBBP. LBFP seems more feasible, and as good as LBTP in terms of electrical synchrony and pacing safety.
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The protein encoded by COQ7 is required for CoQ10 synthesis in humans, hydroxylating 3-demethoxyubiquinol (DMQ10) in the second to last steps of the pathway. COQ7 mutations lead to a primary CoQ10 deficiency syndrome associated with a pleiotropic neurological disorder. This study shows the clinical, physiological, and molecular characterization of four new cases of CoQ10 primary deficiency caused by five mutations in COQ7, three of which have not yet been described, inducing mitochondrial dysfunction in all patients. However, the specific combination of the identified variants in each patient generated precise pathophysiological and molecular alterations in fibroblasts, which would explain the differential in vitro response to supplementation therapy. Our results suggest that COQ7 dysfunction could be caused by specific structural changes that affect the interaction with COQ9 required for the DMQ10 presentation to COQ7, the substrate access to the active site, and the maintenance of the active site structure. Remarkably, patients' fibroblasts share transcriptional remodeling, supporting a modification of energy metabolism towards glycolysis, which could be an adaptive mechanism against CoQ10 deficiency. However, transcriptional analysis of mitochondria-associated pathways showed distinct and dramatic differences between patient fibroblasts, which correlated with the extent of pathophysiological and neurological alterations observed in the probands. Overall, this study suggests that the combination of precise genetic diagnostics and the availability of new structural models of human proteins could help explain the origin of phenotypic pleiotropy observed in some genetic diseases and the different responses to available therapies.
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BACKGROUND: Neurosurgeons may resort to caffeine, alcohol, and various drugs to maintain peak performance as they grapple with work demands and escalated stress. The prevalence of this controversial strategy remains largely unexplored. METHODS: An anonymous survey of 23 questions formulated by our research group was distributed through personal contacts and neurosurgical societies. Inquiries revolved around the use of medications and other substances for job-related reasons. Data were analyzed via regression and descriptive statistics in python. RESULTS: In total, 215 neurosurgeons (43 residents) were included, with 213 disclosing their gender (94 females). Out of all, 9.3% were <30, 38.1% were 30-39, 44.6% were 40-59, and 7.9% were >60 years old. Most (70.7%) practiced in Europe, 18.6% in Asia, 6.5% in North and South America, and the rest in Africa or Australia. While 132 participants stated they consume caffeine to manage challenging schedules, drugs for cognitive and mood enhancement were utilized by 18 and 35 respectively. Alcohol was employed for stress relief by 28 with 4 reporting as heavy drinkers. Drugs posed a solution to sleep disorders for 82, and helped 8 others in strengthening their hand dexterity. Notably, 12 of those claiming drug use initiated it in medical school. Exercise, self-care activities, and relational support were the main alternatives sought. Ultimately, most responders recommended extending mental health assistance and raising awareness about drug use. CONCLUSIONS: Reflecting on our results on job-associated drug use by neurosurgeons, we propose the judicious use of pharmacological or nonpharmacological adjuncts, alongside the prioritization of neurosurgeons' well-being.
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Objectives: Influenza-like illness (ILI) caused by respiratory viruses results in various respiratory clinical manifestations. The ILI002 prospective observational cohort study aimed to describe viral agents, seasonality, and outcomes of patients with ILI during four seasons in the influenza H1N1-pandemic and post-pandemic years (2010-2014). Methods: Patients from six Mexican hospitals were enrolled from April 2010 to March 2014. Clinical data and nasopharyngeal swabs were obtained and tested for viral respiratory pathogens by real-time reverse-transcription polymerase chain reaction. Results: Of the 5662 enrolled participants, 64.9% were adults and 35.1% were children. Among the 5629 participants with single-pathogen detection, rhinovirus (20.2%), influenza virus (11.2%), respiratory syncytial virus (RSV) (7.2%), and coronavirus (6.8%) were the most frequent pathogens. Co-infection occurred in 14.5% of cases; 49.3% of participants required hospitalization, particularly in RSV cases (42.9% adults, 89.6% children). The mortality rate was 2.8% higher among older adult participants and those with comorbidities. Influenza H1N1 had the highest mortality rate, yet almost half of the deceased had no pathogen. Rhinovirus persisted year-round, while influenza, coronavirus, and RSV peaked during cooler months. Conclusions: Analyses showed that some viruses causing ILI may lead to severe disease and hospitalization irrespective of comorbidities. These findings may help in decision-making about public health policies on prevention measures, vaccination, treatment, and administration of health care.
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Monkeypox (mpox) is an orthopoxviral zoonotic disease with a similar but less severe clinical presentation as smallpox. However, immunocompromised patients such as solid organ transplant recipients are at higher risk of developing severe forms of the disease. Herein, we describe the case of a 43-year-old female kidney transplant recipient that manifested severe skin ulcers alongside nodular lung opacities and pleural effusion attributed directly to the monkeypox virus. Notwithstanding the initiation of early treatment with tecovirimat, a satisfactory response was not achieved until a reduction in immunosuppression to everolimus monotherapy, coupled with the transition to cidofovir for antiviral treatment. In conclusion, mpox has the potential to produce a severe form of systemic infection in individuals who have undergone solid organ transplantation, demanding a meticulous approach involving sequential antiviral treatment and modifications to immunosuppressive regimens in order to achieve complete healing.
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Antibiotic resistance is a major public health threat, and alternatives to antibiotic therapy are urgently needed. Immunotherapy, particularly the blockade of inhibitory immune checkpoints, is a leading treatment option in cancer and autoimmunity. In this study, we used a murine model of Salmonella Typhimurium infection to investigate whether immune checkpoint blockade could be applied to bacterial infection. We found that the immune checkpoint T-cell immunoglobulin and ITIM domain (TIGIT) was significantly upregulated on lymphocytes during infection, particularly on CD4+ T cells, drastically limiting their proinflammatory function. Blockade of TIGIT in vivo using monoclonal antibodies was able to enhance immunity and improve bacterial clearance. The efficacy of anti-TIGIT was dependent on the capacity of the antibody to bind to Fc (fragment crystallizable) receptors, giving important insights into the mechanism of anti-TIGIT therapy. This research suggests that targeting immune checkpoints, such as TIGIT, has the potential to enhance immune responses toward bacteria and restore antibacterial treatment options in the face of antibiotic resistance.
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There is increasing awareness of epigenetics's importance in understanding disease etiologies and developing novel therapeutics. An increasing number of publications in the past few years reflect the renewed interest in epigenetic processes and their relationship with food chemicals. However, there needs to be a recent study that accounts for the most recent advances in the area by associating the chemical structures of food and natural product components with their biological activity. Here, we analyze the status of food chemicals and their intersection with natural products in epigenetic research. Using chemoinformatics tools, we compared quantitatively the chemical contents, structural diversity, and coverage in the chemical space of food chemicals with reported epigenetic activity. As part of this work, we built and curated a compound database of food and natural product chemicals annotated with structural information, an epigenetic target activity profile, and the main source of the food chemical or natural product, among other relevant features. The compounds are cross-linked with identifiers from other major public databases such as FooDB and the collection of open natural products, COCONUT. The compound database, the "Epi Food Chemical Database", is accessible in HTML and CSV formats at https://github.com/DIFACQUIM/Epi_food_Chemical_Database.
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The membrane-bound hydrogenase (Mbh) from Pyrococcus furiosus is an archaeal member of the Complex I superfamily. It catalyzes the reduction of protons to H2 gas powered by a [NiFe] active site and transduces the free energy into proton pumping and Na+/H+ exchange across the membrane. Despite recent structural advances, the mechanistic principles of H2 catalysis and ion transport in Mbh remain elusive. Here, we probe how the redox chemistry drives the reduction of the proton to H2 and how the catalysis couples to conformational dynamics in the membrane domain of Mbh. By combining large-scale quantum chemical density functional theory (DFT) and correlated ab initio wave function methods with atomistic molecular dynamics simulations, we show that the proton transfer reactions required for the catalysis are gated by electric field effects that direct the protons by water-mediated reactions from Glu21L toward the [NiFe] site, or alternatively along the nearby His75L pathway that also becomes energetically feasible in certain reaction steps. These local proton-coupled electron transfer (PCET) reactions induce conformational changes around the active site that provide a key coupling element via conserved loop structures to the ion transport activity. We find that H2 forms in a heterolytic proton reduction step, with spin crossovers tuning the energetics along key reaction steps. On a general level, our work showcases the role of electric fields in enzyme catalysis and how these effects are employed by the [NiFe] active site of Mbh to drive PCET reactions and ion transport.
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Hidrógeno , Hidrogenasas , Simulación de Dinámica Molecular , Pyrococcus furiosus , Hidrogenasas/química , Hidrogenasas/metabolismo , Hidrógeno/química , Hidrógeno/metabolismo , Pyrococcus furiosus/enzimología , Protones , Teoría Funcional de la Densidad , Dominio Catalítico , Oxidación-ReducciónRESUMEN
Background: Uncontrolled hypertension is a common problem worldwide, despite the availability of many effective antihypertensive drugs and lifestyle interventions. We assessed the efficacy of a multi-component intervention in individuals with uncontrolled hypertension in a primary care setting. Methods: This study was a randomized, multicenter, parallel, two-arm, single-blind controlled trial performed in primary healthcare centers in Mallorca (Spain). All participants were 35 to 75-years-old and had poorly controlled hypertension. Patients were randomly assigned in a 1:1 ratio to a control group (usual care) or an intervention group (self-monitoring of blood pressure, self-titration of hypertensive medications, dietary interventions, and physical activity interventions). The primary outcome was decrease in the mean SBP at 6 months relative to baseline. Results: A total of 153 participants were randomized to an intervention group (77) or a control group (76). After 6 months, the intervention group had a significantly lower systolic blood pressure (135.1â mmHg [±14.8] vs. 142.7â mmHg [±15.0], adjusted mean difference: 8.7â mmHg [95% CI: 3.4, 13.9], p < 0.001) and a significantly lower diastolic blood pressure (83.5â mmHg [±8.8] vs. 87.00â mmHg [±9.0], adjusted mean difference: 5.4 [95% CI: 2.9, 7.8], p < 0.0001). The intervention group also had significantly more patients who achieved successful blood pressure control (<140/90â mmHg; 54.4% vs. 32.9%, p = 0.011). Discussion: Self-monitoring of blood pressure in combination with self-management of hypertensive medications, diet, and physical activity in a primary care setting leads to significantly lower blood pressure in patients with poorly controlled hypertension.Clinical Trial Registration: ClinicalTrials.gov, identifier ISRCTN14433778.
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Aerobic life is powered by membrane-bound redox enzymes that shuttle electrons to oxygen and transfer protons across a biological membrane. Structural studies suggest that these energy-transducing enzymes operate as higher-order supercomplexes, but their functional role remains poorly understood and highly debated. Here we resolve the functional dynamics of the 0.7 MDa III2IV2 obligate supercomplex from Mycobacterium smegmatis, a close relative of M. tuberculosis, the causative agent of tuberculosis. By combining computational, biochemical, and high-resolution (2.3 Å) cryo-electron microscopy experiments, we show how the mycobacterial supercomplex catalyses long-range charge transport from its menaquinol oxidation site to the binuclear active site for oxygen reduction. Our data reveal proton and electron pathways responsible for the charge transfer reactions, mechanistic principles of the quinone catalysis, and how unique molecular adaptations, water molecules, and lipid interactions enable the proton-coupled electron transfer (PCET) reactions. Our combined findings provide a mechanistic blueprint of mycobacterial supercomplexes and a basis for developing drugs against pathogenic bacteria.
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Microscopía por Crioelectrón , Mycobacterium smegmatis , Mycobacterium smegmatis/metabolismo , Mycobacterium smegmatis/enzimología , Transporte de Electrón , Oxidación-Reducción , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Protones , Complejo III de Transporte de Electrones/metabolismo , Complejo III de Transporte de Electrones/química , Oxígeno/metabolismo , Complejo IV de Transporte de Electrones/metabolismo , Complejo IV de Transporte de Electrones/química , Dominio Catalítico , Modelos MolecularesRESUMEN
New immune checkpoints are emerging in a bid to improve response rates to immunotherapeutic drugs. The adenosine A2A receptor (A2AR) has been proposed as a target for immunotherapeutic development due to its participation in immunosuppression of the tumor microenvironment. Blockade of A2AR could restore tumor immunity and, consequently, improve patient outcomes. Here, we describe the discovery of a potent, selective, and tumor-suppressing antibody antagonist of human A2AR (hA2AR) by phage display. We constructed and screened four single-chain variable fragment (scFv) libraries-two synthetic and two immunized-against hA2AR and antagonist-stabilized hA2AR. After biopanning and ELISA screening, scFv hits were reformatted to human IgG and triaged in a series of cellular binding and functional assays to identify a lead candidate. Lead candidate TB206-001 displayed nanomolar binding of hA2AR-overexpressing HEK293 cells; cross-reactivity with mouse and cynomolgus A2AR but not human A1, A2B, or A3 receptors; functional antagonism of hA2AR in hA2AR-overexpressing HEK293 cells and peripheral blood mononuclear cells (PBMCs); and tumor-suppressing activity in colon tumor-bearing HuCD34-NCG mice. Given its therapeutic properties, TB206-001 is a good candidate for incorporation into next-generation bispecific immunotherapeutics.