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1.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35017299

RESUMEN

Many critical policy decisions, from strategic investments to the allocation of humanitarian aid, rely on data about the geographic distribution of wealth and poverty. Yet many poverty maps are out of date or exist only at very coarse levels of granularity. Here we develop microestimates of the relative wealth and poverty of the populated surface of all 135 low- and middle-income countries (LMICs) at 2.4 km resolution. The estimates are built by applying machine-learning algorithms to vast and heterogeneous data from satellites, mobile phone networks, and topographic maps, as well as aggregated and deidentified connectivity data from Facebook. We train and calibrate the estimates using nationally representative household survey data from 56 LMICs and then validate their accuracy using four independent sources of household survey data from 18 countries. We also provide confidence intervals for each microestimate to facilitate responsible downstream use. These estimates are provided free for public use in the hope that they enable targeted policy response to the COVID-19 pandemic, provide the foundation for insights into the causes and consequences of economic development and growth, and promote responsible policymaking in support of sustainable development.

2.
J Am Chem Soc ; 146(20): 14357-14367, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38726589

RESUMEN

Introducing dynamic behavior into periodic frameworks has borne fruit in the form of flexible porous crystals. The detailed molecular design of frameworks in order to control their collective dynamics is of particular interest, for example, to achieve stimulus-induced behavior. Herein, by varying the degree of rigidity of ditopic pillar linkers, two isostructural flexible metal-organic frameworks (MOFs) with common rigid supermolecular building bilayers were constructed. The subtle substitution of single (in bibenzyl-4,4'-dicarboxylic acid; H2BBDC) with double (in 4,4'-stilbenedicarboxylic acid; H2SDC) C-C bonds in pillared linkers led to markedly different flexible behavior of these two MOFs. Upon the removal of guest molecules, both frameworks clearly show reversible single-crystal-to-single-crystal transformations involving the cis-trans conformation change and a resulting swing of the corresponding pillar linkers, which gives rise to Flex-Cd-MOF-1a and Flex-Cd-MOF-2a, respectively. Strikingly, a more favorable gas-induced dynamic behavior in Flex-Cd-MOF-2a was verified in detail by stepwise C3H6/C3H8 sorption isotherms and the corresponding in situ powder X-ray diffraction experiments. These insights are strongly supported by molecular modeling studies on the sorption mechanism that explores the sorption landscape. Furthermore, a consistency between the macroscopic elasticity and microscopic flexibility of Flex-Cd-MOF-2 was observed. This work fuels a growing interest in developing MOFs with desired chemomechanical functions and presents detailed insights into the origins of flexible MOFs.

3.
J Magn Reson Imaging ; 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38944678

RESUMEN

BACKGROUND: The alteration of left atrial (LA) phasic function in subacute and chronic pulmonary embolism (PE) patients is unclear. PURPOSE: To investigate LA phasic strain and LA-right ventricular (RV) interaction in subacute and chronic PE patients with different degrees of obstruction by MRI-feature tracking (MRI-FT). STUDY TYPE: Retrospective. POPULATION: One hundred three PE patients (54 subacute [2 weeks to 3 months after initial symptoms], 49 chronic [>3 months after initial symptoms]) and 80 controls. FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady state free precession sequence. ASSESSMENT: Patients were divided into mild (pulmonary artery obstruction index [PAOI] < 30%, N = 57), moderate (30% ≤ PAOI < 50%, N = 27), and severe (50% ≥ PAOI, N = 19) PE subgroups. LA reservoir, conduit, and active pump longitudinal strains (εs, εe, and εa) and strain rates (SRs, SRe, and SRa) and biventricular global strains were measured. Determinants of LA strains were investigated. STATISTICAL TESTS: ANOVA, t-tests, Mann-Whitney U tests, linear regression. P < 0.05 was considered statistically significant. RESULTS: For both subacute and chronic PE patients, LA reservoir, conduit, and active pump strains and strain rates were significantly lower than in controls. However, there were no significant differences in LA strains between patients with subacute and chronic PE (P = 0.933, 0.625, and 0.630 for εs, εe, and εa). The severe PE subgroup had significantly higher εa and SRa than the mild and moderate PE subgroups. LA strains were significantly correlated with RV diameter and biventricular strains, and RV diameter (ß = -6.836, -4.084, and -1.899 for εs, εe, and εa) was independently associated with LA strains after adjustment for other factors (R2 = 0.627, 0.536, and 0.437 for εs, εe, and εa). DATA CONCLUSION: LA phasic function evaluated by MRI-FT was significantly impaired in subacute and chronic PE patients, and LA active pump function in the severe PE subgroup was higher than that in the mild and moderate PE subgroups. The independent association between RV diameter and LA strains demonstrates that RV diameter may be an important indicator for monitoring LA dysfunction in PE patients. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

4.
J Magn Reson Imaging ; 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38558213

RESUMEN

BACKGROUND: Alcoholic cardiomyopathy (ACM) can lead to progressive cardiac dysfunction and heart failure, but little is known about biventricular impairment and ventricular interdependence (VI) in ACM patients. PURPOSE: To use cardiac MRI to investigate biventricular impairment and VI in ACM patients. STUDY TYPE: Retrospective. POPULATION: Forty-one male patients with ACM and 45 sex- and age-matched controls. FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession sequence, inversion recovery prepared echo-planar imaging sequence and phase-sensitive inversion recovery sequence. ASSESSMENT: Biventricular structure, function, and global strain (encompassing peak strain [PS], peak systolic, and diastolic strain rate), PS of interventricular septal (IVS), microvascular perfusion (including upslope and time to maximum signal intensity [TTM]), late gadolinium enhancement (LGE), and baseline characteristics were compared between the controls and ACM patients. STATISTICAL TESTS: Student's t-test, Mann-Whitney U test, Pearson's correlation, and multivariable linear regression models with a stepwise selection procedure. A two-tailed P value <0.05 was deemed as statistically significant. RESULTS: Compared to control subjects, ACM patients showed significantly biventricular adverse remodeling, reduced left ventricle (LV) global upslope and prolonged global TTM, and the presence of LGE. ACM patients were characterized by a significant decline in all global strain within the LV, right ventricle (RV), and IVS compared with the controls. RV global PS was significantly associated with LV global PS and IVS PS in radial, circumferential, and longitudinal directions. Multivariable analyses demonstrated the longitudinal PS of IVS was significantly correlated with RV global radial PS (ß = 0.614) and circumferential PS (ß = 0.545). Additionally, RV global longitudinal PS (GLPS) was significantly associated with radial PS of IVS (ß = -0.631) and LV GLPS (ß = 1.096). DATA CONCLUSION: ACM patients exhibited biventricular adverse structural alterations and impaired systolic and diastolic function. This cohort also showed reduced LV microvascular perfusion, the presence of LGE, and unfavorable VI. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.

5.
Acta Cardiol Sin ; 40(3): 300-311, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38779159

RESUMEN

Background: Serum D-dimer level has been associated with worsening outcomes in patients with acute myocardial infarction. This study aimed to explore the association between serum D-dimer level and clinical outcomes in Taiwanese patients with acute myocardial infarction. Methods: We analyzed Tri-Service General Hospital-Coronary Heart Disease registry data related to patients with acute myocardial infarction who were admitted between January 2014 and December 2018. A total of 748 patients were enrolled and categorized into high (≥ 495 ng/ml) and low (< 495 ng/ml) D-dimer groups. The primary endpoint was in-hospital mortality, and secondary endpoints were post-discharge mortality and post-discharge major adverse cardiovascular events. Results: Overall, 139 patients died, with 77 from cardiovascular causes and 62 from non-cardiovascular causes. In-hospital mortality was higher in the high D-dimer group than in the low D-dimer group. Among the patients alive at discharge, those with a high D-dimer level had higher cardiovascular mortality and future major adverse cardiovascular events than those with a low D-dimer level. Multivariate Cox regression analysis revealed that higher serum D-dimer levels were significantly associated with higher risks of in-hospital mortality [hazard ratio (HR) = 1.11; 95% confidence interval (CI), 1.06-1.16, p < 0.001], subsequent cardiovascular mortality after discharge (HR = 1.15; 95% CI, 1.08-1.22, p < 0.001), and major adverse cardiovascular events (HR = 1.10; 95% CI, 1.04-1.16, p < 0.001). Conclusions: This is the first study in Taiwan to demonstrate that a higher baseline serum D-dimer level was independently associated with higher risks of in-hospital mortality, post-discharge mortality, and major adverse cardiovascular events in patients with acute myocardial infarction.

6.
Mol Cancer ; 22(1): 99, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37353784

RESUMEN

BACKGROUND: Lung adenocarcinoma (LUAD) is a common type of lung cancer with a high risk of metastasis, but the exact molecular mechanisms of metastasis are not yet understood. METHODS: This study acquired single-cell transcriptomics profiling of 11 distal normal lung tissues, 11 primary LUAD tissues, and 4 metastatic LUAD tissues from the GSE131907 dataset. The lung multicellular ecosystems were characterized at a single-cell resolution, and the potential mechanisms underlying angiogenesis and metastasis of LUAD were explored. RESULTS: We constructed a global single-cell landscape of 93,610 cells from primary and metastatic LUAD and found that IGF2BP2 was specifically expressed both in a LUAD cell subpopulation (termed as LUAD_IGF2BP2), and an endothelial cell subpopulation (termed as En_IGF2BP2). The LUAD_IGF2BP2 subpopulation progressively formed and dominated the ecology of metastatic LUAD during metastatic evolution. IGF2BP2 was preferentially secreted by exosomes in the LUAD_IGF2BP2 subpopulation, which was absorbed by the En_IGF2BP2 subpopulation in the tumor microenvironment. Subsequently, IGF2BP2 improved the RNA stability of FLT4 through m6A modification, thereby activating the PI3K-Akt signaling pathway, and eventually promoting angiogenesis and metastasis. Analysis of clinical data showed that IGF2BP2 was linked with poor overall survival and relapse-free survival for LUAD patients. CONCLUSIONS: Overall, these findings provide a novel insight into the multicellular ecosystems of primary and metastatic LUAD, and demonstrate that a specific LUAD_IGF2BP2 subpopulation is a key orchestrator promoting angiogenesis and metastasis, with implications for the gene regulatory mechanisms of LUAD metastatic evolution, representing themselves as potential antiangiogenic targets.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Humanos , Metilación , Ecosistema , Células Endoteliales , Fosfatidilinositol 3-Quinasas , Recurrencia Local de Neoplasia , Adenocarcinoma del Pulmón/genética , Neoplasias Pulmonares/genética , Microambiente Tumoral , Proteínas de Unión al ARN/genética
7.
Small ; 19(22): e2300821, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36869658

RESUMEN

The pore dimension and surface property directly dictate the transport of guests, endowing diverse gas selective adsorptions to porous materials. It is highly relevant to construct metal-organic frameworks (MOFs) with designable functional groups that can achieve feasible pore regulation to improve their separation performances. However, the role of functionalization in different positions or degrees within framework on the separation of light hydrocarbon has rarely been emphasized. In this context, four isoreticular MOFs (TKL-104-107) bearing dissimilar fluorination are rationally screened out and afforded intriguing differences in the adsorption behavior of C2 H6 and C2 H4 . Ortho-fluoridation of carboxyl allows TKL-105-107 to exhibit enhanced structural stabilities, impressive C2 H6 adsorption capacities (>125 cm3 g-1 ) and desirable inverse selectivities (C2 H6 over C2 H4 ). The more modified ortho-fluorine group and meta-fluorine group of carboxyl have improved the C2 H6 /C2 H4 selectivity and adsorption capacity, respectively, and the C2 H6 /C2 H4 separation potential can be well optimized via linker fine-fluorination. Meanwhile, dynamic breakthrough experiments proved that TKL-105-107 can be used as highly efficient C2 H6 -selective adsorbents for C2 H4 purification. This work highlights that the purposeful functionalization of pore surfaces facilitates the assembly of highly efficient MOF adsorbents for specific gas separation.

8.
Annu Rev Nutr ; 42: 201-226, 2022 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-35588443

RESUMEN

The original description of dietary methionine restriction (MR) used semipurified diets to limit methionine intake to 20% of normal levels, and this reduction in dietary methionine increased longevity by ∼30% in rats. The MR diet also produces paradoxical increases in energy intake and expenditure and limits fat deposition while reducing tissue and circulating lipids and enhancing overall insulin sensitivity. In the years following the original 1993 report, a comprehensive effort has been made to understand the nutrient sensing and signaling systems linking reduced dietary methionine to the behavioral, physiological, biochemical, and transcriptional components of the response. Recent work has shown that transcriptional activation of hepatic fibroblast growth factor 21 (FGF21) is a key event linking the MR diet to many but not all components of its metabolic phenotype. These findings raise the interesting possibility of developing therapeutic, MR-based diets that produce the beneficial effects of FGF21 by nutritionally modulating its transcription and release.


Asunto(s)
Resistencia a la Insulina , Metionina , Animales , Dieta , Ingestión de Energía , Metabolismo Energético , Factores de Crecimiento de Fibroblastos/genética , Factores de Crecimiento de Fibroblastos/metabolismo , Humanos , Hígado/metabolismo , Metionina/metabolismo , Ratas
9.
Cardiovasc Diabetol ; 22(1): 178, 2023 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-37443014

RESUMEN

OBJECTIVE: Type 2 diabetes mellitus (T2DM) and anemia are related to some cardiovascular diseases and can predict poor outcomes. Both of them can damage the heart in their own ways, but their combined effects have not been well explored. This study aimed to explore the combined effects of T2DM and anemia and the interaction between left atrial (LA) and left ventricular (LV) function by cardiac magnetic resonance (CMR). MATERIALS AND METHODS: A total of 177 T2DM patients without anemia, 68 T2DM patients with anemia and 73 sex-matched controls were retrospectively enrolled in this study from June 2015 to September 2022. Their LA phasic function and LV function parameters were compared to explore the combined effects of T2DM and anemia and the interaction between LA and LV function. Univariate and multivariate linear regression were done to explore the independent factors influencing LA phasic function and LV function. RESULTS: Compared with controls and T2DM patients without anemia, T2DM patients with anemia were older and had higher heart rate, higher creatinine, lower estimated glomerular filtration rate (eGFR) and lower hemoglobin (Hb) (all p < 0.05). LV global longitudinal peak strain (GLPS) significantly declined from T2DM patients with anemia to T2DM patients without anemia to controls (p < 0.001). LA volumetric function and strain were significantly impaired in T2DM patients with anemia compared with the other groups (all p < 0.05). In addition to age, eGFR, Hb and HbA1c, the LV GLPS was independently associated with all LA phasic strains (LA reservoir strain, ß =0.465; LA conduit strain, ß = 0.450; LA pump strain, ß = 0.360, all p < 0.05). LA global conduit strain, total LA ejection fraction (LAEF) and active LAEF were independently associated with LV GLPS and LVEF. CONCLUSION: Both LA and LV function were severely impaired in T2DM patients with anemia, and T2DM and anemia were independently associated with LA phasic function. Deleterious interaction between LA function and LV function would happen in T2DM patients with or without anemia. Timely and effective monitoring and management of both LA and LV function will benefit T2DM patients.


Asunto(s)
Anemia , Fibrilación Atrial , Diabetes Mellitus Tipo 2 , Disfunción Ventricular Izquierda , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Estudios Retrospectivos , Función Ventricular Izquierda , Atrios Cardíacos/diagnóstico por imagen , Espectroscopía de Resonancia Magnética , Anemia/complicaciones , Anemia/diagnóstico , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología
10.
Cardiovasc Diabetol ; 22(1): 154, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37381007

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) frequently coexists with obstructive coronary artery disease (OCAD), which are at increased risk for cardiovascular morbidity and mortality. This study aimed to investigate the impact of coronary obstruction on myocardial microcirculation function in T2DM patients, and explore independent predictors of reduced coronary microvascular perfusion. METHODS: Cardiac magnetic resonance (CMR) scanning was performed on 297 T2DM patients {188 patients without OCAD [T2DM(OCAD -)] and 109 with [T2DM(OCAD +)]} and 89 control subjects. CMR-derived perfusion parameters, including upslope, max signal intensity (MaxSI), and time to maximum signal intensity (TTM) in global and segmental (basal, mid-ventricular, and apical slices) were measured and compared among observed groups. According to the median of Gensini score (64), T2DM(OCAD +) patients were subdivided into two groups. Univariable and multivariable linear regression analyses were performed to identify independent predictors of microcirculation dysfunction. RESULTS: T2DM(OCAD -) patients, when compared to control subjects, had reduced upslope and prolonged TTM in global and all of three slices (all P < 0.05). T2DM(OCAD +) patients showed a significantly more severe impairment of microvascular perfusion than T2DM(OCAD -) patients and control subjects with a more marked decline upslope and prolongation TTM in global and three slices (all P < 0.05). From control subjects, through T2DM(OCAD +) patients with Gensini score ≤ 64, to those patients with Gensini score > 64 group, the upslope declined and TTM prolonged progressively in global and mid-ventricular slice (all P < 0.05). The presence of OCAD was independently correlated with reduced global upslope (ß = - 0.104, P < 0.05) and global TTM (ß = 0.105, P < 0.05) in patients with T2DM. Among T2DM(OCAD +) patients, Gensini score was associated with prolonged global TTM (r = 0.34, P < 0.001). CONCLUSIONS: Coronary artery obstruction in the context of T2DM exacerbated myocardial microcirculation damage. The presence of OCAD and Gensini score were independent predictors of decreased microvascular function. TRIAL REGISTRATION: Retrospectively registered.


Asunto(s)
Enfermedad de la Arteria Coronaria , Oclusión Coronaria , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Corazón , Perfusión , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/etiología
11.
Cardiovasc Diabetol ; 22(1): 15, 2023 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-36694151

RESUMEN

OBJECTIVE: To explore the additive effects of anemia on left ventricular (LV) global strains in patients with type 2 diabetes mellitus (T2DM) with or without anemia via cardiac magnetic resonance (CMR) feature tracking technology. MATERIALS AND METHODS: 236 T2DM patients with or without anemia and 67 controls who underwent CMR examination were retrospectively enrolled. LV function parameters, LV global radial peak strain (GRPS), longitudinal peak strain (GLPS), and circumferential peak strain (GCPS) were used to analyze the function and global strain of the heart. One-way analysis of variance and the chi-square test were used for intergroup analysis. Multivariable linear regression analysis was performed for the two T2DM groups to explore factors associated with LV global strains. RESULTS: The T2DM group with anemia was oldest and had a lowest hemoglobin (Hb) concentration, lowest estimated glomerular filtration rate, highest LV end-systolic volume index, highest end-diastolic volume index and highest LV mass index than the control group and T2DM without anemia group (all P ≤ 0.001). Besides, The LV global peak strains in all three directions worsened successively from the control group to the T2DM without anemia group to the T2DM with anemia group (all p < 0.001). Among all clinical indices, the decrease in Hb was independently associated with the worsening in GRPS (ß = 0.237, p = 0.001), GCPS (ß = 0.326, p < 0.001), and GLPS (ß = 0.265, p < 0.001). CONCLUSION: Anemia has additive deleterious effects on LV function and LV global strains in patients with T2DM. Regular detection and early intervention of anemia might be beneficial for T2DM patients.


Asunto(s)
Anemia , Diabetes Mellitus Tipo 2 , Disfunción Ventricular Izquierda , Humanos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/diagnóstico , Corazón/diagnóstico por imagen , Corazón/fisiopatología , Estudios Retrospectivos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Disfunción Ventricular Izquierda/etiología , Función Ventricular Izquierda , Anemia/complicaciones , Imagen por Resonancia Magnética
12.
J Magn Reson Imaging ; 2023 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-37873997

RESUMEN

BACKGROUND: Patients with repaired tetralogy of Fallot (rTOF) continue to face a heightened risk of deteriorating cardiac function, and quantitative techniques of cardiac MRI-derived cardiac structure and function provide an opportunity to explore the causes and mechanisms of cardiac deterioration. PURPOSE: To explore right-left ventricular interdependence in rTOF patients before and after the onset of right ventricular (RV) heart failure. STUDY TYPE: Retrospective. POPULATION: One hundred eighteen rTOF patients (21.85 [16.74, 29.20] years, 58 females) and 34 controls (23.5 [21, 26.5] years, 17 females) that underwent cardiac MRI were analyzed, with rTOF patients being further subdivided into those with preserved RV function (N = 54) and those that experienced RV heart failure (N = 64). FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession sequence. ASSESSMENT: RV, left ventricular (LV), and septal strain; RV and LV volume. STATISTICAL TESTS: Chi-squared tests or Fisher's exact test, One-way ANOVAs with Bonferroni's post hoc test, Pearson/Spearman correlation, and multivariate backward linear regression analysis. A two-tailed P < 0.05 was deemed as the significance threshold. RESULTS: The MRI-derived RV, LV, and septal strain decreased sequentially in controls, patients with preserved RV function, and patients with RV heart failure, with a good intra-observer (0.909-0.964) and inter-observer (0.879-0.937) agreement. Correlations between LV and RV strain were found to change sequentially with RV function and were the closest in rTOF patients with RV heart failure (r = -0.270 to 0.506). Correlations between RV volume and septal strain was variable in controls (r = 0.483 to -0.604), patients with preserved RV function (r = -0.034 to -0.295), and patients with RV heart failure (r = -0.026 to 0.500). Multivariate analyses revealed that the RV longitudinal strain was independently correlated with LV strain in three directions in rTOF patients with RV heart failure (Radial -0.70 [-1.33, -0.06]; Circumferential 0.44 [0.17, 0.72]; Longitudinal 0.54 [0.26, 0.81]). DATA CONCLUSION: In rTOF patients, the coupling between RV volume and septal strain was broken during RV function compensation, and the adverse effect of RV on LV deformation was highest in patients with RV heart failure. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: Stage 5.

13.
J Magn Reson Imaging ; 2023 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-37864419

RESUMEN

BACKGROUND: Pulmonary hypertension (PH) results in right ventricular (RV) dysfunction, subsequently leading to left ventricular (LV) impairment. The mechanism underlying ventricular interdependence is largely uninvestigated. PURPOSE: To explore the biventricular dysfunction and the ventricular interdependence in PH patients. STUDY TYPE: Retrospective. POPULATION: One hundred and seven PH patients (mean pulmonary artery pressure >20 mmHg) and 72 age- and sex-matched controls with cardiac magnetic resonance imaging (MRI) studies. FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession sequence. ASSESSMENT: LV and RV ejection fractions (EF) and RV and LV radial, circumferential, and longitudinal strains were assessed using commercial software. Strains were compared between controls, PH patients with preserved RVEF (RVEF ≥40%, N = 48), and PH patients with reduced RVEF (RVEF <40%, N = 59). STATISTICAL TESTS: Chi-squared tests or Fisher's exact test, t tests or Mann-Whitney U test, one-way ANOVA with Bonferroni's post hoc correction or Kruskal-Wallis test, Pearson or Spearman correlation, and multivariable linear regression analysis. A two-tailed P < 0.05 was deemed statistically significant. RESULTS: RV strain decreased sequentially from controls, through PH with preserved RVEF, to PH with reduced RVEF. PH patients with reduced RVEF had significantly lower LV strain, especially septal strain, and LV peak diastolic strain rate compared with both controls and PH patients with preserved RVEF. Multivariable analyses showed that RVEF was independently correlated with LV strain; furthermore, independent of RVEF, RV strain was significantly correlated with LV strain (LVGRS: ß = 0.416; LVGCS: ß = -0.371; LVGLS: ß = 0.283). DATA CONCLUSION: Subclinical impairment of RV function was found in PH with preserved RVEF. LV strain was impaired when RV was dysfunctional, which was associated with worsening RV strain. Therefore, while focusing on improving RV function, LV dysfunction in PH patients should also be monitored and treated early in order to slow the progression of the disease. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 3.

14.
Pharmacol Res ; 196: 106933, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37729957

RESUMEN

Both environmental and genetic factors contribute to the etiology of autoimmune thyroid disease (AITD) including Graves' disease (GD) and Hashimoto's thyroiditis (HT). However, the exact pathogenesis and interactions that occur between environmental factors and genes remain unclear, and therapeutic targets require further investigation due to limited therapeutic options. To solve such problems, this study utilized single-cell transcriptome, whole transcriptome, full-length transcriptome (Oxford nanopore technology), and metabolome sequencing to examine thyroid lesion tissues from 2 HT patients and 2 GD patients as well as healthy thyroid tissue from 1 control subject. HT patients had increased ATF4-positive thyroid follicular epithelial (ThyFoEp) cells, which significantly increased endoplasmic reticulum stress. The enhanced sustained stress resulted in cell death mainly including apoptosis and necroptosis. The ATF4-based global gene regulatory network and experimental validation revealed that N6-methyladenosine (m6A) reader hnRNPC promoted the transcriptional activity, synthesis, and translation of ATF4 through mediating m6A modification of ATF4. Increased ATF4 expression initiated endoplasmic reticulum stress signaling, which when sustained, caused apoptosis and necroptosis in ThyFoEp cells, and mediated HT development. Targeting hnRNPC and ATF4 notably decreased ThyFoEp cell death, thus ameliorating disease progression. Collectively, this study reveals the mechanisms by which microenvironmental cells in HT and GD patients trigger and amplify the thyroid autoimmune cascade response. Furthermore, we identify new therapeutic targets for the treatment of autoimmune thyroid disease, hoping to provide a potential way for targeted therapy.

15.
Inorg Chem ; 62(44): 18014-18019, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37862124

RESUMEN

Due to their intrinsic structural features, the design and synthesis of a new type of zeolite-like metal-organic frameworks (ZMOFs) is highly desirable but challenging. Herein, solvothermal reactions between an angular dicarboxylate linker and rare-earth (RE) ions afforded two RE-MOFs, namely, Tb-ZMOF-2 and Tb-ZMOF-3, respectively. Structural analyses reveal that Tb-ZMOF-2 encompasses a novel [446482] cage, while Tb-ZMOF-3 contains nonanuclear (i.e., D6R) and hexanuclear (i.e., D4R) RE clusters simultaneously, subsequently resulting in two new zeolitic topologies. Thanks to its high surface area and pore volume, Tb-ZMOF-2 demonstrates considerably high gravimetric and volumetric methane storage working capacities.

16.
Inorg Chem ; 62(49): 20513-20519, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38008909

RESUMEN

With the development of crystalline porous materials toward methane storage, the stability issue of metal-organic framework (MOF) materials has caused great concern despite high working capacity. Considering the high stability of zirconium-based MOFs and effective functions of amide groups toward gas adsorption, herein, a series of UiO-66 type of Zr-MOFs, namely, Zr-fcu-H/F/CH3/OH, were successfully designed and synthesized by virtue of amide-functionalized dicarboxylate ligands bearing distinct side groups (i.e., -H, -F, -CH3, and -OH) and ZrCl4 in the presence of trifluoroacetic acid as the modulator. Single-crystal X-ray diffraction and topology analyses reveal that these compounds are archetypal fcu MOFs encompassing octahedral and tetrahedral cages, respectively. The N2 sorption isotherms and acid-base stability tests demonstrate that the materials possess not only relatively high surface areas, pore volumes, and appropriate pore sizes but also great hydrolytic stabilities ranging pH = 3-11. Furthermore, the volumetric methane storage working capacities of Zr-fcu-H, Zr-fcu-F, Zr-fcu-CH3, and Zr-fcu-OH at 298/273 K and 80 bar are 187/217, 175/193, 167/187, and 154/171 cm3 (STP) cm-3, respectively, which indicate that the zirconium-based crystalline porous materials are capable of storing relatively high amounts of methane.

17.
Inorg Chem ; 62(17): 6751-6758, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37083265

RESUMEN

Metal-organic frameworks (MOFs) have been recognized as a potential platform for the development of tunable luminophores owing to their highly modulable structures and components. Herein, two MOF luminophores based on Cd(II) ions, 1,3,5-tri(4-pyridinyl)benzene (TPB), and 1,4-dicarboxybenzene (H2BDC) were constructed. The directed assembly of the metal ions and organic linkers results in [Cd2(BDC)2(TPB)(H2O)]·x(solvent) (MOF-1) featuring TPB-based blue fluorescence centered at 425 nm. By introducing anthracene as the structure directing agent (SDA) for assembly regulation, [Cd2(BDC)(TPB)2(NO3)2]·x(solvent) (MOF-2) was obtained, which reveals anthracene feeding-dependent high tunable emission in the 517-650 nm range. Detailed components, photophysical properties, and structural characteristics investigations of MOF-2 indicate the TPB and NO3- interactions as the origin of its redshifted emission compared with that of MOF-1. Furthermore, the fluorescence of MOF-2 was found to be regulatable by the anthracene feeding based on the SDA-determined crystallinity of the crystalline sample. All these results provided a unique example of the structural and fluorescence regulation of MOF luminophores.

18.
Clin Oral Investig ; 27(12): 7871-7880, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37987822

RESUMEN

OBJETIVES: To investigate the positional changes in the temporomandibular joint (TMJ) disc-condyle-fossa complex of patients with anterior disc displacement without reduction (ADDWoR) and to evaluate the effect of disc repositioning (DR) surgery. MATERIAL AND METHODS: Fifteen patients with unilateral ADDWoR (30 joints) were included. MRI of the TMJ was performed at T0 (1 week before surgery), T1 (1 month after surgery), and T2 (9-12 months after surgery). The glenoid fossa, disc, and condyle were reconstructed and analyzed using Mimics software. RESULTS: In the patients with unilateral ADDWoR, the disc on the ADD side showed a tendency to downward shift in the coronal direction and forward shift in the sagittal direction; the condyle of ADD side showed a tendency to backward shift in the sagittal direction and upward shift in the coronal direction. When comparing the same ADDwoR TMJ at T0, T1, and T2, the disc was found to move upward and backward after DR surgery at T1 and T2, and the condyle was found to move upward and backward after DR surgery at T1 but returned to the original position at T2. CONCLUSIONS: ADDWoR leads to forward and downward displacement of the disc relative to the condyle and upward displacement of the condyle relative to the tuberosity. DR surgery improved upon the structural abnormalities of the TMJ complex, for which stability was maintained as determined in the 9 to 12 month postoperative follow-up. CLINIC RELEVANCE: DR surgery effectively and constantly improves the positional abnormalities of the TMJ complex.


Asunto(s)
Luxaciones Articulares , Trastornos de la Articulación Temporomandibular , Humanos , Cóndilo Mandibular/cirugía , Trastornos de la Articulación Temporomandibular/cirugía , Luxaciones Articulares/cirugía , Disco de la Articulación Temporomandibular/cirugía , Imagen por Resonancia Magnética , Articulación Temporomandibular/cirugía
19.
Sensors (Basel) ; 23(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37631557

RESUMEN

The autonomous driving technology based on deep reinforcement learning (DRL) has been confirmed as one of the most cutting-edge research fields worldwide. The agent is enabled to achieve the goal of making independent decisions by interacting with the environment and learning driving strategies based on the feedback from the environment. This technology has been widely used in end-to-end driving tasks. However, this field faces several challenges. First, developing real vehicles is expensive, time-consuming, and risky. To further expedite the testing, verification, and iteration of end-to-end deep reinforcement learning algorithms, a joint simulation development and validation platform was designed and implemented in this study based on VTD-CarSim and the Tensorflow deep learning framework, and research work was conducted based on this platform. Second, sparse reward signals can cause problems (e.g., a low-sample learning rate). It is imperative for the agent to be capable of navigating in an unfamiliar environment and driving safely under a wide variety of weather or lighting conditions. To address the problem of poor generalization ability of the agent to unknown scenarios, a deep deterministic policy gradient (DDPG) decision-making and planning method was proposed in this study in accordance with a multi-task fusion strategy. The main task based on DRL decision-making planning and the auxiliary task based on image semantic segmentation were cross-fused, and part of the network was shared with the main task to reduce the possibility of model overfitting and improve the generalization ability. As indicated by the experimental results, first, the joint simulation development and validation platform built in this study exhibited prominent versatility. Users were enabled to easily substitute any default module with customized algorithms and verify the effectiveness of new functions in enhancing overall performance using other default modules of the platform. Second, the deep reinforcement learning strategy based on multi-task fusion proposed in this study was competitive. Its performance was better than other DRL algorithms in certain tasks, which improved the generalization ability of the vehicle decision-making planning algorithm.

20.
J Exp Bot ; 73(1): 168-181, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34467995

RESUMEN

Pollen grains transport the sperm cells through the style tissue via a fast-growing pollen tube to the ovaries where fertilization takes place. Pollen tube growth requires a precisely regulated network of cellular as well as molecular events including the activity of the plasma membrane H+ ATPase, which is known to be regulated by reversible protein phosphorylation and subsequent binding of 14-3-3 isoforms. Immunodetection of the phosphorylated penultimate threonine residue of the pollen plasma membrane H+ ATPase (LilHA1) of Lilium longiflorum pollen revealed a sudden increase in phosphorylation with the start of pollen tube growth. In addition to phosphorylation, pH modulated the binding of 14-3-3 isoforms to the regulatory domain of the H+ ATPase, whereas metabolic components had only small effects on 14-3-3 binding, as tested with in vitro assays using recombinant 14-3-3 isoforms and phosphomimicking substitutions of the threonine residue. Consequently, local H+ influxes and effluxes as well as pH gradients in the pollen tube tip are generated by localized regulation of the H+ ATPase activity rather than by heterogeneous localized distribution in the plasma membrane.


Asunto(s)
Proteínas 14-3-3 , ATPasas de Translocación de Protón , Proteínas 14-3-3/metabolismo , Membrana Celular/metabolismo , Concentración de Iones de Hidrógeno , Fosforilación , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polen/metabolismo , Tubo Polínico/metabolismo , ATPasas de Translocación de Protón/metabolismo
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