RESUMEN
Metformin is the most prescribed drug for DM2, but its site and mechanism of action are still not well established. Here, we investigated the effects of metformin on basolateral intestinal glucose uptake (BIGU), and its consequences on hepatic glucose production (HGP). In diabetic patients and mice, the primary site of metformin action was the gut, increasing BIGU, evaluated through PET-CT. In mice and CaCo2 cells, this increase in BIGU resulted from an increase in GLUT1 and GLUT2, secondary to ATF4 and AMPK. In hyperglycemia, metformin increased the lactate (reducing pH and bicarbonate in portal vein) and acetate production in the gut, modulating liver pyruvate carboxylase, MPC1/2, and FBP1, establishing a gut-liver crosstalk that reduces HGP. In normoglycemia, metformin-induced increases in BIGU is accompanied by hypoglycemia in the portal vein, generating a counter-regulatory mechanism that avoids reductions or even increases HGP. In summary, metformin increases BIGU and through gut-liver crosstalk influences HGP.
Asunto(s)
Tracto Gastrointestinal , Glucosa , Hígado , Metformina , Animales , Humanos , Ratones , Células CACO-2 , Diabetes Mellitus Tipo 2 , Glucosa/metabolismo , Hipoglucemiantes/farmacología , Hígado/metabolismo , Metformina/farmacología , Tomografía Computarizada por Tomografía de Emisión de Positrones , Tracto Gastrointestinal/metabolismoRESUMEN
The fluctuating hydrogen bridge bonded network of liquid water at ambient conditions entails a varied ensemble of the underlying constituting H2O molecular moieties. This is mirrored in a manifold of the H2O molecular potentials. Subnatural line width resonant inelastic X-ray scattering allowed us to quantify the manifold of molecular potential energy surfaces along the H2O symmetric normal mode and the local asymmetric O-H bond coordinate up to 1 and 1.5 Å, respectively. The comparison of the single H2O molecular potentials and spectroscopic signatures with the ambient conditions liquid phase H2O molecular potentials is done on various levels. In the gas phase, first principles, Morse potentials, and stepwise harmonic potential reconstruction have been employed and benchmarked. In the liquid phase the determination of the potential energy manifold along the local asymmetric O-H bond coordinate from resonant inelastic X-ray scattering via the bound state oxygen 1s to [Formula: see text] resonance is treated within these frameworks. The potential energy surface manifold along the symmetric stretch from resonant inelastic X-ray scattering via the oxygen 1s to [Formula: see text] resonance is based on stepwise harmonic reconstruction. We find in liquid water at ambient conditions H2O molecular potentials ranging from the weak interaction limit to strongly distorted potentials which are put into perspective to established parameters, i.e., intermolecular O-H, H-H, and O-O correlation lengths from neutron scattering.
Asunto(s)
Hidrógeno , Agua , Técnicas de Química Analítica , Oxígeno/química , Agua/química , Rayos XRESUMEN
BACKGROUND: Refractory upper abdominal pain or lower back pain (retroperitoneal pain syndrome) related to celiac plexus involvement characterises pancreatic and other upper gastrointestinal malignancies and is an unmet need. We hypothesised that ablative radiation delivered to the celiac plexus would decrease pain. METHODS: This multicentre, single-arm, phase 2 study was done at eight hospitals in five countries (Israel, Poland, Canada, the USA, and Portugal). Eligible patients aged 18 years or older with an average pain level of 5-10 on the Brief Pain Inventory short form (BPI-SF), an Eastern Cooperative Oncology Group performance status score of 0-2, and either pancreatic cancer or other tumours involving the celiac axis, received a single fraction of 25 Gy of external-beam photons to the celiac plexus. The primary endpoint was complete or partial pain response based on a reduction of the BPI-SF average pain score of 2 points or more from baseline to 3 weeks after treatment. All evaluable patients with stable pain scores were included in response assessment. The trial is registered with ClinicalTrials.gov, NCT03323489, and is complete. FINDINGS: Between Jan 3, 2018, and Dec 28, 2021, 125 patients were treated, 90 of whom were evaluable. Patients were followed up until death. Median age was 65·5 years (IQR 58·3-71·8), 50 (56%) were female and 40 (44%) were male, 83 (92%) had pancreatic cancer, and 77 (86%) had metastatic disease. Median baseline BPI-SF average pain score was 6 (IQR 5-7). Of the 90 evaluable patients at 3 weeks, 48 (53%; 95% CI 42-64) had at least a partial pain response. The most common grade 3-4 adverse events, irrespective of attribution, were abdominal pain (35 [28%] of 125) and fatigue (23 [18%]). 11 serious adverse events of grade 3 or worse were recorded. Two grade 3 serious adverse events were probably attributed to treatment by the local investigators (abdominal pain [n=1] and nausea [n=1]), and nine were possibly attributed to treatment (seven were grade 3: blood bilirubin increased [n=1], duodenal haemorrhage [n=2], abdominal pain [n=2], and progressive disease [n=2]; and two were grade 5: gastrointestinal bleed from suspected varices 24 days after treatment [n=1] and progressive disease [advanced pancreatic cancer] 89 days after treatment [n=1]). INTERPRETATION: Celiac plexus radiosurgery could potentially be a non-invasive palliative option for patients with retroperitoneal pain syndrome. Further investigation by means of a randomised comparison with conventional celiac block or neurolysis is warranted. FUNDING: Gateway for Cancer Research and the Israel Cancer Association.
Asunto(s)
Dolor en Cáncer , Plexo Celíaco , Manejo del Dolor , Radiocirugia , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Radiocirugia/efectos adversos , Manejo del Dolor/métodos , Dolor en Cáncer/etiología , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Dimensión del Dolor , Anciano de 80 o más Años , Resultado del Tratamiento , Adulto , Dolor Abdominal/etiologíaRESUMEN
C-H bond activation reactions with transition metals typically proceed via the formation of alkane σ-complexes, where an alkane C-H σ-bond binds to the metal. Due to the weak nature of metal-alkane bonds, σ-complexes are challenging to characterize experimentally. Here, we establish the complete pathways of photochemical formation of the model σ-complex Cr(CO)5-alkane from Cr(CO)6 in octane solution and characterize the nature of its metal-ligand bonding interactions. Using femtosecond optical absorption spectroscopy, we find photoinduced CO dissociation from Cr(CO)6 to occur within the 100 fs time resolution of the experiment. Rapid geminate recombination by a fraction of molecules is found to occur with a time constant of 150 fs. The formation of bare Cr(CO)5 in its singlet ground state is followed by complexation of an octane molecule from solution with a time constant of 8.2 ps. Picosecond X-ray absorption spectroscopy at the Cr L-edge and O K-edge provides unique information on the electronic structure of the Cr(CO)5-alkane σ-complex from both the metal and ligand perspectives. Based on clear experimental observables, we find substantial destabilization of the lowest unoccupied molecular orbital upon coordination of the C-H bond to the undercoordinated Cr center in the Cr(CO)5-alkane σ-complex, and we define this as a general, orbital-based descriptor of the metal-alkane bond. Our study demonstrates the value of combining optical and X-ray spectroscopic methods as complementary tools to study the stability and reactivity of alkane σ-complexes in their role as the decisive intermediates in C-H bond activation reactions.
RESUMEN
Schwarzites are porous (spongy-like) carbon allotropes with negative Gaussian curvatures. They are proposed by Mackay and Terrones inspired by the works of the German mathematician Hermann Schwarz on Triply-Periodic Minimal Surfaces (TPMS). This review presents and discusses the history of schwarzites and their place among curved carbon nanomaterials. The main works on schwarzites are summarized and are available in the literature. Their unique structural, electronic, thermal, and mechanical properties are discussed. Although the synthesis of carbon-based schwarzites remains elusive, recent advances in the synthesis of zeolite-templates nanomaterials have brought them closer to reality. Atomic-based models of schwarzites are translated into macroscale ones that are 3D-printed. These 3D-printed models are exploited in many real-world applications, including water remediation and biomedical ones.
RESUMEN
Deep-water coral reefs are found worldwide and harbor biodiversity levels that are comparable to their shallow-water counterparts. However, the genetic diversity and population structure of deep-water species remain poorly explored, and historical taxonomical issues still need to be resolved. Here we used microsatellite markers as well as ultraconserved elements (UCE) and exons to shed light on the population structure, genetic diversity, and phylogenetic position of the genus Madrepora, which contains M. oculata, one of the most widespread scleractinian species. Population structure of 107 samples from three Southwestern Atlantic sedimentary basins revealed the occurrence of a cryptic species, herein named M. piresae sp. nov. (authored by Kitahara, Capel and Zilberberg), which can be found in sympatry with M. oculata. Phylogeny reconstructions based on 134 UCEs and exon regions corroborated the population genetic data, with the recovery of two well-supported groups, and reinforced the polyphyly of the family Oculinidae. In order to better accommodate the genus Madrepora, while reducing taxonomical confusion associated with the name Madreporidae, we propose the monogeneric family Bathyporidae fam. nov. (authored by Kitahara, Capel, Zilberberg and Cairns). Our findings advance the knowledge on the widespread deep-water genus Madrepora, resolve a long-standing question regarding the phylogenetic position of the genus, and highlight the need of a worldwide review of the genus.
Asunto(s)
Antozoos , Agua , Animales , Filogenia , Arrecifes de Coral , BiodiversidadRESUMEN
Sickle cell disease (SCD) is an inherited hemolytic anemia caused by a single point mutation in the ß-globin gene of hemoglobin that leads to synthesis of sickle hemoglobin (HbS) in red blood cells (RBCs). HbS polymerizes in hypoxic conditions, leading to intravascular hemolysis, release of free hemoglobin and heme, and increased adhesion of blood cells to the endothelial vasculature, which causes painful vaso-occlusion and organ damage. HbS polymerization kinetics are strongly dependent on the intracellular HbS concentration; a relatively small reduction in cellular HbS concentration may prevent HbS polymerization and its sequelae. We hypothesized that iron restriction via blocking ferroportin, the unique iron transporter in mammals, might reduce HbS concentration in RBCs, thereby decreasing hemolysis, improving blood flow, and preventing vaso-occlusive events. Indeed, vamifeport (also known as VIT-2763), a clinical-stage oral ferroportin inhibitor, reduced hemolysis markers in the Townes model of SCD. The RBC indices of vamifeport-treated male and female Townes mice exhibited changes attributable to iron-restricted erythropoiesis: decreased corpuscular hemoglobin concentration mean and mean corpuscular volume, as well as increased hypochromic and microcytic RBC fractions. Furthermore, vamifeport reduced plasma soluble VCAM-1 concentrations, which suggests lowered vascular inflammation. Accordingly, intravital video microscopy of fluorescently labeled blood cells in the microvasculature of Townes mice treated with vamifeport revealed diminished adhesion to the endothelium and improved hemodynamics. These preclinical data provide a strong proof-of-concept for vamifeport in the Townes model of SCD and support further development of this compound as a potential novel therapy in SCD.
Asunto(s)
Anemia de Células Falciformes , Hemólisis , Anemia de Células Falciformes/complicaciones , Animales , Proteínas de Transporte de Catión , Modelos Animales de Enfermedad , Femenino , Hemodinámica , Hemoglobina Falciforme/genética , Hemoglobina Falciforme/metabolismo , Hemoglobinas/metabolismo , Hierro/uso terapéutico , Masculino , Mamíferos/metabolismo , RatonesRESUMEN
Photodissociation of ironpentacarbonyl [1Fe(CO)5] in solution generates transient species in different electronic states, which we studied theoretically. From ab initio molecular dynamics simulations in ethanol solution, the closed-shell parent compound 1Fe(CO)5 is found to interact weakly with the solvent, whereas the irontetracarbonyl [Fe(CO)4] species, formed after photodissociation, has a strongly spin-dependent behavior. It coordinates a solvent molecule tightly in the singlet state [1Fe(CO)4] and weakly in the triplet state [3Fe(CO)4]. From the simulations, we have gained insights into intersystem crossing in solvated irontetracarbonyl based on the distinct structural differences induced by the change in multiplicity. Alternative forms of coordination between 1Fe(CO)4 and functional groups of the ethanol molecule are simulated, and a quantum chemical investigation of the energy landscape for the coordinated irontetracarbonyl gives information about the interconversion of different transient species in solution. Furthermore, insights from the simulations, in which we find evidence of a solvent exchange mechanism, challenge the previously proposed mechanism of chain walking for under-coordinated metal carbonyls in solution.
RESUMEN
INTRODUCTION: Despite advances in medical therapy, approximately 33% of Crohn's disease (CD) patients will need surgery within 5 years after initial diagnosis. Several surgical approaches to CD have been proposed including small bowel resection, strictureplasty, and combined surgery with resection plus strictureplasty. Here, we utilize the American College of Surgeons (ACS) national surgical quality registry (NSQIP) to perform a comprehensive analysis of 30-day outcomes between these three surgical approaches for CD. METHODS: The authors queried the ACS-NSQIP database between 2015 and 2020 for all patients undergoing open or laparoscopic resection of small bowel or strictureplasty for CD using CPT and IC-CM 10. Outcomes of interest included length of stay, discharge disposition, wound complications, 30-day related readmission, and reoperation. RESULTS: A total of 2578 patients were identified; 87% of patients underwent small bowel resection, 5% resection with strictureplasty, and 8% strictureplasty alone. Resection plus strictureplasty (combined surgery) was associated with the longest operative time (p = 0.002). Patients undergoing small bowel resection had the longest length of hospital stay (p = 0.030) and the highest incidence of superficial/deep wound infection (44%, p = 0.003) as well as the highest incidence of sepsis (3.5%, p = 0.03). Small bowel resection was found to be associated with higher odds of wound complication compared to combined surgery (OR 2.09, p = 0.024) and strictureplasty (1.9, p = 0.005). CONCLUSION: Our study shows that various surgical approaches for CD are associated with comparable outcomes in 30-day related reoperation and readmission, or disposition following surgery between all three surgical approaches. However, small bowel resection displayed higher odds of developing post-operative wound complications.
Asunto(s)
Enfermedad de Crohn , Intestino Delgado , Humanos , Enfermedad de Crohn/cirugía , Intestino Delgado/cirugía , Intestino Delgado/patología , Estudios Retrospectivos , Resultado del Tratamiento , Masculino , Femenino , Adulto , Tiempo de Internación , Complicaciones Posoperatorias/etiología , Readmisión del Paciente , Reoperación , Persona de Mediana Edad , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Procedimientos Quirúrgicos del Sistema Digestivo/métodos , Sistema de RegistrosRESUMEN
BACKGROUND: Peripheral arterial disease (PAD) is characterised by obstruction or narrowing of the large arteries of the lower limbs, usually caused by atheromatous plaques. Most people with PAD who experience intermittent leg pain (intermittent claudication) are typically treated with secondary prevention strategies, including medical management and exercise therapy. Lower limb revascularisation may be suitable for people with significant disability and those who do not show satisfactory improvement after conservative treatment. Some studies have suggested that lower limb revascularisation for PAD may not confer significantly more benefits than supervised exercise alone for improved physical function and quality of life. It is proposed that supervised exercise therapy as adjunctive treatment after successful lower limb revascularisation may confer additional benefits, surpassing the effects conferred by either treatment alone. OBJECTIVES: To assess the effects of a supervised exercise programme versus standard care following successful lower limb revascularisation in people with PAD. SEARCH METHODS: We searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, two other databases, and two trial registers, most recently on 14 March 2023. SELECTION CRITERIA: We included randomised controlled trials which compared supervised exercise training following lower limb revascularisation with standard care following lower limb revascularisation in adults (18 years and older) with PAD. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were maximum walking distance or time (MWD/T) on the treadmill, six-minute walk test (6MWT) total distance, and pain-free walking distance or time (PFWD/T) on the treadmill. Our secondary outcomes were changes in the ankle-brachial index, all-cause mortality, changes in health-related quality-of-life scores, reintervention rates, and changes in subjective measures of physical function. We analysed continuous data by determining the mean difference (MD) and 95% confidence interval (CI), and dichotomous data by determining the odds ratio (OR) with corresponding 95% CI. We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: We identified seven studies involving 376 participants. All studies involved participants who received either additional supervised exercise or standard care after lower limb revascularisation. The studies' exercise programmes varied, and included supervised treadmill walking, combined exercise, and circuit training. The duration of exercise therapy ranged from six weeks to six months; follow-up time ranged from six weeks to five years. Standard care also varied between studies, including no treatment or advice to stop smoking, lifestyle modifications, or best medical treatment. We classified all studies as having some risk of bias concerns. The certainty of the evidence was very low due to the risk of bias, inconsistency, and imprecision. The meta-analysis included only a subset of studies due to concerns regarding data reporting, heterogeneity, and bias in most published research. The evidence was of very low certainty for all the review outcomes. Meta-analysis comparing changes in maximum walking distance from baseline to end of follow-up showed no improvement (MD 159.47 m, 95% CI -36.43 to 355.38; I2 = 0 %; 2 studies, 89 participants). In contrast, exercise may improve the absolute maximum walking distance at the end of follow-up compared to standard care (MD 301.89 m, 95% CI 138.13 to 465.65; I2 = 0 %; 2 studies, 108 participants). Moreover, we are very uncertain if there are differences in the changes in the six-minute walk test total distance from baseline to treatment end between exercise and standard care (MD 32.6 m, 95% CI -17.7 to 82.3; 1 study, 49 participants), and in the absolute values at the end of follow-up (MD 55.6 m, 95% CI -2.6 to 113.8; 1 study, 49 participants). Regarding pain-free walking distance, we are also very uncertain if there are differences in the mean changes in PFWD from baseline to treatment end between exercise and standard care (MD 167.41 m, 95% CI -11 to 345.83; I2 = 0%; 2 studies, 87 participants). We are very uncertain if there are differences in the absolute values of ankle-brachial index at the end of follow-up between the intervention and standard care (MD 0.01, 95% CI -0.11 to 0.12; I2 = 62%; 2 studies, 110 participants), in mortality rates at the end of follow-up (OR 0.92, 95% CI 0.42 to 2.00; I2 = 0%; 6 studies, 346 participants), health-related quality of life at the end of follow-up for the physical (MD 0.73, 95% CI -5.87 to 7.33; I2 = 64%; 2 studies, 105 participants) and mental component (MD 1.04, 95% CI -6.88 to 8.95; I2 = 70%; 2 studies, 105 participants) of the 36-item Short Form Health Survey. Finally, there may be little to no difference in reintervention rates at the end of follow-up between the intervention and standard care (OR 0.91, 95% CI 0.23 to 3.65; I2 = 65%; 5 studies, 252 participants). AUTHORS' CONCLUSIONS: There is very uncertain evidence that additional exercise therapy after successful lower limb revascularisation may improve absolute maximal walking distance at the end of follow-up compared to standard care. Evidence is also very uncertain about the effects of exercise on pain-free walking distance, six-minute walk test distance, quality of life, ankle-brachial index, mortality, and reintervention rates. Although it is not possible to confirm the effectiveness of supervised exercise compared to standard care for all outcomes, studies did not report any harm to participants from this intervention after lower limb revascularisation. Overall, the evidence incorporated into this review was very uncertain, and additional evidence is needed from large, well-designed, randomised controlled studies to more conclusively demonstrate the role additional exercise therapy has after lower limb revascularisation in people with PAD.
Asunto(s)
Terapia por Ejercicio , Claudicación Intermitente , Enfermedad Arterial Periférica , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Humanos , Terapia por Ejercicio/métodos , Enfermedad Arterial Periférica/terapia , Claudicación Intermitente/terapia , Prueba de Paso , Caminata , Extremidad Inferior/irrigación sanguínea , Persona de Mediana Edad , Sesgo , AncianoRESUMEN
INTRODUCTION: Combined high sedentary time (ST) and low moderate-to-vigorous physical activity (MVPA) has been associated with adverse cardiovascular events. However, accurately assessing ST and MVPA in older adults is challenging in clinical practice. PURPOSE: To investigate whether step count can identify older adults with unhealthier movement behavior (high ST/low MVPA) and poorer cardiometabolic profile. METHODS: Cross-sectional study (n = 258; 66 ± 5 years). Step count, ST, and MVPA were assessed by hip accelerometry during 7 days. The cardiometabolic profile was assessed using a continuous metabolic syndrome score (cMetS), including blood pressure, HDL-cholesterol, triglycerides, fasting glucose, and waist circumference. Receiving operating curve analysis was used to test the performance of step count in identifying older adults with unhealthier movement behavior (highest tertile of ST/lowest tertile of MVPA). Healthier movement behavior was defined as lowest tertile of ST/highest tertile of MVPA, with neutral representing the remaining combinations of ST/MVPA. RESULTS: A total of 40 participants (15.5%) were identified with unhealthier movement behavior (ST ≥ 11.4 h/day and MVPA ≤ 10 min/day). They spent ~73% and 0.4% of waking hours in ST and MVPA, respectively. Step count identified those with unhealthier movement behavior (area under the curve 0.892, 0.850-0.934; cutoff: ≤5263 steps/day; sensitivity/specificity: 83%/81%). This group showed a higher cMetS compared with neutral (ß = .25, p = .028) and healthier movement behavior groups (ß = .41, p = .008). CONCLUSION: Daily step count appears to be a practical, simple metric for identifying community-dwelling older adults with concomitant high ST and low MVPA, indicative of unhealthier movement behavior, who have a poorer cardiometabolic profile.
RESUMEN
BACKGROUND: To explore the influence of sociodemographic, behavioral, clinical, and anthropometric factors on the association between sex and functional capacity in patients with peripheral arterial disease. METHODS: A cross-sectional study was conducted with patients aged more than 45 years, diagnosed with peripheral artery disease (PAD), from 2 Brazilian hospitals. Data on sociodemographic characteristics, behavioral risk factors, clinical profile, and anthropometric measurements were collected. Functional capacity was assessed using the 6-min walk test and the Walking Impairment Questionnaire. Statistical analyses, including t-tests, chi-square tests, and logistic regression, were performed to assess the relationships between sex, functional capacity, and potential influencing factors. RESULTS: Among the 262 patients with PAD, 67 were women and 113 were men. Women exhibited lower absolute functional capacity and lower Walking Impairment Questionnaire scores compared to men, even after adjusting for potential confounders. However, relative functional capacity did not significantly differ between sexes after adjusting for variables. Pain-free walking distance was also lower in women compared to that in men, but this association lost significance after adjusting for sociodemographic factors. CONCLUSIONS: Women with PAD had lower absolute functional capacity compared to men, influenced by various factors such as sociodemographic, behavioral, clinical, and anthropometric factors. However, the relative functional capacity was similar between genders, being influenced only by behavioral factors, while for the distance walked until pain, the association was lost after adjustments for sociodemographic factors.
Asunto(s)
Enfermedad Arterial Periférica , Humanos , Femenino , Masculino , Estudios Transversales , Resultado del Tratamiento , Enfermedad Arterial Periférica/diagnóstico , Prueba de Paso , Conducta Sexual , Caminata , Claudicación IntermitenteRESUMEN
This longitudinal study aimed to analyze the influence of physical activity (PA) on the relationship between body adiposity and cardiac autonomic modulation (CAM) in women survivors of breast cancer. We collected body adiposity through electrical bioimpedance considering body fat percentage (BFP), CAM through heart rate variability (considering RMSSD, SDNN, PNN50, LF (m2), HF (m2), SD1 indexes and SD1/SD2 ratio) and PA through a questionnaire in 64 participants (58.0 ± 9.6 years), recruited through the local association of support for breast cancer and by direct indications from city mastologists. After insertion of PA into the multivariate statistical model, significant attenuation was observed in the relationship between body adiposity and CAM for the indices: SDNN (ß = -0.94; 95 percent CI: -1.93; 0.04; p = .060) and SD1/SD2 (ß = -0.01;95 percent CI = -0.02; 0.001; p = .065). In conclusion, it was observed that PA was able to mitigate the relationships between BFP and CAM (considering SDNN index and SD1/SD2 ratio) in breast cancer survivors.
Asunto(s)
Neoplasias de la Mama , Supervivientes de Cáncer , Sindactilia , Humanos , Femenino , Adiposidad , Estudios Longitudinales , Obesidad , Ejercicio Físico/fisiología , Frecuencia Cardíaca/fisiologíaRESUMEN
PURPOSE: Physical disabilities may exacerbate the natural decline in sleep quality that occurs with aging. In the current study, we assessed sleep quality and medicinal sleep aid use among 87 community-dwelling older adults with (n = 24) and without (n = 63) physical disabilities. METHOD: Sleep quality, duration, and efficiency were assessed subjectively with the Pittsburgh Sleep Quality Index. Sleep duration and efficiency were objectively measured with actigraphy. Participants self-reported medicinal sleep aid use. RESULTS: Significant group differences were observed in sleep duration measured objectively (p = 0.01) and subjectively (p = 0.04). No other group differences were observed for sleep factors (p > 0.05) or medicinal sleep aid use (p = 0.41). CONCLUSION: Findings show that physical disability may be a factor in sleep duration; however, physical disability was not found to be associated with worsened sleep perception or greater reliance on medicinal sleep aids. Future research should consider longer objective actigraphy assessment windows and explore potential subgroup differences in sex and race/ethnicity. [Journal of Gerontological Nursing, 50(7), 12-18.].
Asunto(s)
Personas con Discapacidad , Vida Independiente , Calidad del Sueño , Humanos , Anciano , Masculino , Femenino , Anciano de 80 o más Años , Pobreza , Actigrafía , Sueño/fisiología , Persona de Mediana EdadRESUMEN
In response to the global threat of antimicrobial resistance (AMR), the Capturing Data on Antimicrobial Resistance Patterns and Trends in Use in Regions of Asia (CAPTURA) project worked with microbiology laboratories, pharmacies, and local governments in South Asia and Southeast Asia to expand the volume of historical and current data available on AMR and antimicrobial use and to identify gaps in data and areas for quality improvement. When the CAPTURA project completed its country-level engagement in the first half of 2022, the consortium brought together local, regional, and global AMR stakeholders for a virtual regional workshop to review data outputs from the project and share strategies to inform national and regional efforts to combat AMR. This paper summarizes the main topics presented in the workshop held from 28 to 30 June 2022. As such, it highlights lessons learned from the project and strategies to fight AMR. Although CAPTURA has been invaluable to countries and information from the project is already being used, barriers concerning data quality and sharing remain. Regional-level initiatives should continue to build on the momentum gained from the CAPTURA project in supporting national-level surveillance and data quality improvements to inform critical decisions around planning, policies, and clinical care. Project findings have highlighted that issues with antimicrobial resistance and use are wide ranging across countries. Going forward, building on the current foundations and tailoring approaches to meet local needs and capacities will be fundamental in combatting AMR.
Asunto(s)
Antiinfecciosos , Exactitud de los Datos , Humanos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Asia , Farmacorresistencia Bacteriana , Laboratorios , PolíticasRESUMEN
Background: This study aimed to identify the blood pressure (BP) responses during different types of isometric exercises (IE) in adults and to evaluate whether BP responses according to IE is influenced by the characteristics of participants and exercise protocols. Methods: The search was conducted in PubMed, Cochrane Central, SPORTDiscus, and LILACS databases in June 2020. Random effects models with a 95% confidence interval and p < 0.05 were used in the analyses. Results: Initially, 3201 articles were found and, finally, 102 studies were included in this systematic review, seven of which were included in the meta-analysis comparing handgrip to other IE. Two-knee extension and deadlift promoted greater increases in systolic (+9.8 mmHg; p = 0.017; I 2 = 74.5% and +26.8 mmHg; p ≤ 0.001; I 2 = 0%, respectively) and diastolic (+7.9 mmHg; p = 0.022; I 2 = 68.6% and +12.4 mmHg; p ≤ 0.001; I 2 = 36.3%, respectively) BP compared to handgrip. Men, middle-aged/elderly adults, hypertensive individuals, and protocols with higher intensities potentiate the BP responses to handgrip exercise (p ≤ 0.001). Conclusions: IE involving larger muscle groups elicit greater BP responses than those involving smaller muscle masses, especially in men, middle-aged/elderly adults and hypertensive individuals. Future studies should directly compare BP responses during various types of IE in different populations.
RESUMEN
Adaptive behavior requires learning about the structure of one's environment to derive optimal action policies, and previous studies have documented transfer of such structural knowledge to bias choices in new environments. Here, we asked whether people could also acquire and transfer more abstract knowledge across different task environments, specifically expectations about cognitive control demands. Over three experiments, participants (Amazon Mechanical Turk workers; N = ~80 adults per group) performed a probabilistic card-sorting task in environments of either a low or high volatility of task rule changes (requiring low or high cognitive flexibility, respectively) before transitioning to a medium-volatility environment. Using reinforcement-learning modeling, we consistently found that previous exposure to high task rule volatilities led to faster adaptation to rule changes in the subsequent transfer phase. These transfers of expectations about cognitive flexibility demands were both task independent (Experiment 2) and stimulus independent (Experiment 3), thus demonstrating the formation and generalization of environmental structure knowledge to guide cognitive control.
Asunto(s)
Cognición , Aprendizaje , Adulto , Humanos , Adaptación Psicológica , Cognición/fisiología , Generalización Psicológica , Aprendizaje/fisiología , Refuerzo en Psicología , Análisis y Desempeño de Tareas , Masculino , Femenino , Adulto Joven , Persona de Mediana EdadRESUMEN
The atomic specificity of X-ray spectroscopies provides a distinct perspective on molecular electronic structure. For 3d metal coordination and organometallic complexes, the combination of metal- and ligand-specific X-ray spectroscopies directly interrogates metal-ligand covalency-the hybridization of metal and ligand electronic states. Resonant inelastic X-ray scattering (RIXS), the X-ray analog of resonance Raman scattering, provides access to all classes of valence excited states in transition-metal complexes, making it a particularly powerful means of characterizing the valence electronic structure of 3d metal complexes. Recent advances in X-ray free-electron laser sources have enabled RIXS to be extended to the ultrafast time domain. We review RIXS studies of two archetypical photochemical processes: charge-transfer excitation in ferricyanide and ligand photodissociation in iron pentacarbonyl. These studies demonstratefemtosecond-resolution RIXS can directly characterize the time-evolving electronic structure, including the evolution of the metal-ligand covalency.
Asunto(s)
Complejos de Coordinación , Elementos de Transición , Electrónica , Ligandos , Metales , Espectrometría Raman , Rayos XRESUMEN
DNA-encoded libraries (DELs) are widely used in the discovery of drug candidates, and understanding their design principles is critical for accessing better libraries. Most DELs are combinatorial in nature and are synthesized by assembling sets of building blocks in specific topologies. In this study, different aspects of library topology were explored and their effect on DEL properties and chemical diversity was analyzed. We introduce a descriptor for DEL topological assignment (DELTA) and use it to examine the landscape of possible DEL topologies and their coverage in the literature. A generative topographic mapping analysis revealed that the impact of library topology on chemical space coverage is secondary to building block selection. Furthermore, it became apparent that the descriptor used to analyze chemical space dictates how structures cluster, with the effects of topology being apparent when using three-dimensional descriptors but not with common two-dimensional descriptors. This outcome points to potential challenges of attempts to predict DEL productivity based on chemical space analyses alone. While topology is rather inconsequential for defining the chemical space of encoded compounds, it greatly affects possible interactions with target proteins as illustrated in docking studies using NAD/NADP binding proteins as model receptors.
Asunto(s)
ADN , Descubrimiento de Drogas , Descubrimiento de Drogas/métodos , ADN/química , Biblioteca de GenesRESUMEN
Reactions that occur under physiological conditions find diverse uses in the chemical and biological sciences. However, the limitations that biological systems place on chemical reactions restrict the number of such bioorthogonal reactions. A profound understanding of the mechanistic principles and structure-reactivity trends of these transformations is therefore critical to access new and improved versions of bioorthogonal chemistry. The present article reviews the mechanisms and substituent effects of some of the principal metal-free bioorthogonal reactions based on inverse-electron demand Diels-Alder reactions, 1,3-dipolar cycloadditions, and the Staudinger reaction. Mechanisms of modified versions that link these reactions to a dissociative step are further discussed. The presented summary is anticipated to aid the advancement of bioorthogonal chemistry.