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1.
Nature ; 615(7954): 907-912, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36949194

RESUMEN

Immunoglobulin M (IgM) is the first antibody to emerge during embryonic development and the humoral immune response1. IgM can exist in several distinct forms, including monomeric, membrane-bound IgM within the B cell receptor (BCR) complex, pentameric and hexameric IgM in serum and secretory IgM on the mucosal surface. FcµR, the only IgM-specific receptor in mammals, recognizes different forms of IgM to regulate diverse immune responses2-5. However, the underlying molecular mechanisms remain unknown. Here we delineate the structural basis of the FcµR-IgM interaction by crystallography and cryo-electron microscopy. We show that two FcµR molecules interact with a Fcµ-Cµ4 dimer, suggesting that FcµR can bind to membrane-bound IgM with a 2:1 stoichiometry. Further analyses reveal that FcµR-binding sites are accessible in the context of IgM BCR. By contrast, pentameric IgM can recruit four FcµR molecules to bind on the same side and thereby facilitate the formation of an FcµR oligomer. One of these FcµR molecules occupies the binding site of the secretory component. Nevertheless, four FcµR molecules bind to the other side of secretory component-containing secretory IgM, consistent with the function of FcµR in the retrotransport of secretory IgM. These results reveal intricate mechanisms of IgM perception by FcµR.


Asunto(s)
Proteínas Reguladoras de la Apoptosis , Inmunoglobulina M , Proteínas de la Membrana , Animales , Linfocitos B/citología , Linfocitos B/metabolismo , Sitios de Unión , Membrana Celular/metabolismo , Microscopía por Crioelectrón , Cristalografía por Rayos X , Inmunoglobulina M/química , Inmunoglobulina M/metabolismo , Inmunoglobulina M/ultraestructura , Mamíferos , Unión Proteica , Multimerización de Proteína , Receptores de Antígenos de Linfocitos B/química , Receptores de Antígenos de Linfocitos B/metabolismo , Receptores de Antígenos de Linfocitos B/ultraestructura , Componente Secretorio/química , Componente Secretorio/metabolismo , Componente Secretorio/ultraestructura , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/ultraestructura , Proteínas Reguladoras de la Apoptosis/química , Proteínas Reguladoras de la Apoptosis/metabolismo , Proteínas Reguladoras de la Apoptosis/ultraestructura
2.
PLoS Biol ; 21(12): e3002433, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38091366

RESUMEN

The emerging and global spread of a novel plasmid-mediated colistin resistance gene, mcr-1, threatens human health. Expression of the MCR-1 protein affects bacterial fitness and this cost correlates with lipid A perturbation. However, the exact molecular mechanism remains unclear. Here, we identified the MCR-1 M6 variant carrying two-point mutations that conferred co-resistance to ß-lactam antibiotics. Compared to wild-type (WT) MCR-1, this variant caused severe disturbance in lipid A, resulting in up-regulation of L, D-transpeptidases (LDTs) pathway, which explains co-resistance to ß-lactams. Moreover, we show that a lipid A loading pocket is localized at the linker domain of MCR-1 where these 2 mutations are located. This pocket governs colistin resistance and bacterial membrane permeability, and the mutated pocket in M6 enhances the binding affinity towards lipid A. Based on this new information, we also designed synthetic peptides derived from M6 that exhibit broad-spectrum antimicrobial activity, exposing a potential vulnerability that could be exploited for future antimicrobial drug design.


Asunto(s)
Colistina , Proteínas de Escherichia coli , Humanos , Colistina/farmacología , Antibacterianos/farmacología , Antibióticos Betalactámicos , Lípido A , Péptidos Antimicrobianos , Monobactamas , Plásmidos , Farmacorresistencia Bacteriana/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Pruebas de Sensibilidad Microbiana
3.
Hum Genomics ; 18(1): 41, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38654324

RESUMEN

BACKGROUND: Congenital anomalies of the kidney and urinary tract (CAKUT) are prevalent birth defects. Although pathogenic CAKUT genes are known, they are insufficient to reveal the causes for all patients. Our previous studies indicated GEN1 as a pathogenic gene of CAKUT in mice, and this study further investigated the correlation between GEN1 and human CAKUT. METHODS: In this study, DNA from 910 individuals with CAKUT was collected; 26 GEN1 rare variants were identified, and two GEN1 (missense) variants in a non-CAKUT group were found. Mainly due to the stability results of the predicted mutant on the website, in vitro, 10 variants (eight CAKUT, two non-CAKUT) were selected to verify mutant protein stability. In addition, mainly based on the division of the mutation site located in the functional region of the GEN1 protein, 8 variants (six CAKUT, two non-CAKUT) were selected to verify enzymatic hydrolysis, and the splice variant GEN1 (c.1071 + 3(IVS10) A > G) was selected to verify shear ability. Based on the results of in vitro experiments and higher frequency, three sites with the most significant functional change were selected to build mouse models. RESULTS: Protein stability changed in six variants in the CAKUT group. Based on electrophoretic mobility shift assay of eight variants (six CAKUT, two non-CAKUT), the enzymatic hydrolysis and DNA-binding abilities of mutant proteins were impaired in the CAKUT group. The most serious functional damage was observed in the Gen1 variant that produced a truncated protein. A mini-gene splicing assay showed that the variant GEN1 (c.1071 + 3(IVS10) A > G) in the CAKUT group significantly affected splicing function. An abnormal exon10 was detected in the mini-gene splicing assay. Point-mutant mouse strains were constructed (Gen1: c.1068 + 3 A > G, p.R400X, and p.T105R) based on the variant frequency in the CAKUT group and functional impairment in vitro study and CAKUT phenotypes were replicated in each. CONCLUSION: Overall, our findings indicated GEN1 as a risk factor for human CAKUT.


Asunto(s)
Anomalías Urogenitales , Reflujo Vesicoureteral , Animales , Femenino , Humanos , Masculino , Ratones , Predisposición Genética a la Enfermedad , Riñón/anomalías , Riñón/patología , Riñón/metabolismo , Mutación/genética , Estabilidad Proteica , Factores de Riesgo , Sistema Urinario/anomalías , Sistema Urinario/patología , Anomalías Urogenitales/genética , Anomalías Urogenitales/patología , Reflujo Vesicoureteral/genética , Reflujo Vesicoureteral/patología
4.
Small ; 20(1): e2304512, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37653588

RESUMEN

The development of high performance electrocatalysts for effective hydrogen production is urgently needed. Herein, three hybrid catalysts formed by WS2 and Co-based metal-organic frameworks (MOFs) derivatives are constructed, in which the small amount of W in the MOFs derivatives acts as a bridge to provide the charge transfer channel and enhance the stability. In addition, the effects of the surface charge distribution on the catalytic performance are fully investigated. Due to the optimal interfacial electron coupling and rearrangement as well as its unique porous morphology, WS2 @W-CoPx exhibits superior bifunctional performance in alkaline media with low overpotentials in hydrogen evolution reaction (HER) (62 mV at 10 mA cm-2 ) and oxygen evolution reaction (OER) (278 mV at 100 mA cm-2 ). For overall water splitting (OWS), WS2 @W-CoPx only requires a cell voltage of 1.78 V at 50 mA cm-2 and maintains good stability within 72 h. Density functional theory calculations verify that the combination of W-CoPx with WS2 can effectively enhance the activity of OER and HER with weakened OH (or O) adsorption and enhanced H atom adsorption. This work provides a feasible idea for the design and practical application of WS2 or phosphide-based catalysts in OWS.

5.
Opt Express ; 32(5): 8484-8495, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38439503

RESUMEN

In photonic systems, bilayer or multilayer systems exhibit numerous exciting phenomena induced by twisting. Thus, it is highly desired to explore the twisting effect by engineering the light-matter interactions. Optical torque, an important means in optical micromanipulation, can rotate micro-objects in various ways, enabling a wide range of promising applications. In this study, we present an interesting phenomenon called "pure optical twist" (POT), which emerges when a bilayer structure with specific symmetry is illuminated by counter-propagating lights with opposite spin and/or orbital angular momentum. Remarkably, this leads to zero net optical torque but yet possesses an interesting mechanical effect of bilayer system twisting. The crucial determinant of this phenomenon is the rotational symmetries of each layer, which govern the allowed azimuthal channels of the scattered wave. When the rotational symmetries do not allow these channels to overlap, no resultant torque is observed. Our work will encourage further exploration of the twisting effect through engineered light-matter interactions. This opens up the possibility of creating twisted bilayer systems using optical means, and constructing a stable bilayer optical motor that maintains identical rotation frequencies for both layers.

6.
Analyst ; 149(2): 304-349, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38051130

RESUMEN

With the rapid development of fluorescent nanoparticles (FNPs), such as CDs, QDs, and MOFs, the construction of FNP-based probes has played a key role in improving chemical sensors. Ratiometric fluorescent probes exhibit distinct advantages, such as resistance to environmental interference and achieving visualization. Thus, FNP-based dual-emission ratiometric fluorescent probes (DRFPs) have rapidly developed in the field of metal ion and small molecule detection in the past few years. In this review, firstly we introduce the fluorescence sensing mechanisms; then, we focus on the strategies for the fabrication of DRFPs, including hybrid FNPs, single FNPs with intrinsic dual emission and target-induced new emission, and DRFPs based on auxiliary nanoparticles. In the section on hybrid FNPs, methods to assemble two types of FNPs, such as chemical bonding, electrostatic interaction, core satellite or core-shell structures, coordination, and encapsulation, are introduced. In the section on single FNPs with intrinsic dual emission, methods for the design of dual-emission CDs, QDs, and MOFs are discussed. Regarding target-induced new emission, sensitization, coordination, hydrogen bonding, and chemical reaction induced new emissions are discussed. Furthermore, in the section on DRFPs based on auxiliary nanoparticles, auxiliary nanomaterials with the inner filter effect and enzyme mimicking activity are discussed. Finally, the existing challenges and an outlook on the future of DRFP are presented. We sincerely hope that this review will contribute to the quick understanding and exploration of DRFPs by researchers.

7.
Inorg Chem ; 63(8): 3637-3641, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38341868

RESUMEN

Two unique 22-core sandwich {[Mn6Mo6O37]Ln3[MnMo6O24]} (Ln = La or Pr) units have been assembled, featuring an undisclosed {Mn6Mo6} cluster. This assembly is subsequently integrated into two three-dimensional polyoxometalate organic frameworks, which exhibit one-dimensional hydrophilic hexagonal channels formed by six intertwined 63 helical chains, leading to effective proton conduction primarily facilitated by an abundance of water molecules within the channels.

8.
Surg Endosc ; 38(6): 3405-3415, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38724646

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) is a common co-morbidity in patients who receive esophagectomy and has unfavorable effects on glucose and lipid metabolism in patients. This study examines how weight and glycolipid metabolism change in patients with T2DM following esophagectomy. METHODS: This retrospective, one-center, observational analysis with a propensity score matching analysis (PSM) included 114 patients who underwent esophageal surgery in the Department of Cardiothoracic Surgery, the 900th Hospital of Joint Logistic Support Force from 2017 to 2020, which were separated into T2DM group and Non-T2DM group. Weight, body mass index (BMI), fasting plasma glucose (FPG), triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL), and low-density lipoprotein (LDL) were measured and analyzed before and after the operation. RESULTS: Two groups showed similar reductions in weight and BMI after surgery. In the T2DM group, weight decreased from 63.10(10.31) before surgery to 55.10(11.60) kg at 6 months (P < 0.001) with BMI decreasing from 22.67 (2.90) to 19.77 (3.48); While in the Non-T2DM group, weight decreased from 61.42 (8.46) to 53.19 (9.26) kg at 6 months after surgery with BMI decline from 22.49 (2.77) before operation to 19.45 (3.08) at 6 months after surgery. Fasting plasma glucose levels showed a significant decrease (P = 0.035) in the T2DM group at a six-month point of 7.00 (2.21) mmol/L compared to preoperative levels of 7.67 (2.32) mmol/L. HDL levels increased significantly in the Non-T2DM group at six months postoperatively at 1.52 (0.05) with P < 0.001 compared to preoperative levels of 1.22(0.04) mmol/L. TG, LDL, and TC levels decreased significantly in both groups from the preoperative to the 6-month point. CONCLUSIONS: Esophagectomy induces weight loss in T2DM and Non-T2DM groups, improves long-term glucose metabolism in the T2DM group, and enhances lipid metabolism in both groups. Further research is needed to understand their mechanisms.


Asunto(s)
Glucemia , Diabetes Mellitus Tipo 2 , Esofagectomía , Puntaje de Propensión , Pérdida de Peso , Humanos , Diabetes Mellitus Tipo 2/cirugía , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/metabolismo , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Glucemia/metabolismo , Anciano , Glucolípidos/metabolismo , Índice de Masa Corporal , Neoplasias Esofágicas/cirugía
9.
BMC Vet Res ; 20(1): 43, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38308297

RESUMEN

BACKGROUND: Bovine viral diarrhea (BVD) is an acute febrile infectious disease caused by the bovine viral diarrhea virus (BVDV), which has brought huge economic losses to the world's cattle industry. At present, commercial inactivated BVDV vaccines may cause some adverse reactions during use. This study aims to develop a safer and more efficient inactivated BVDV vaccine. METHODS: Here, we described the generation and preclinical efficacy of a hydrogen peroxide (H2O2) inactivated BVDV type 1 vaccine in mice, and administered it separately with commercial vaccine (formaldehyde inactivated) in mice to study its efficacy. RESULTS: The BVDV type 1 IgG, IFN- γ, IL-4 and neutralizing antibody in the serum of the H2O2 inactivated vaccine group can be maintained in mice for 70 days. The IgG level reached its maximum value of 0.67 on the 42nd day, significantly higher than the commercial formaldehyde inactivated BVDV type 1 vaccine. IFN- γ and IL-4 reached their maximum values on the 28th day after immunization, at 123.16 pg/ml and 143.80 pg/ml, respectively, slightly higher than commercial vaccines, but the effect was not significant. At the same time the BVDV-1 neutralizing antibody titer reached a maximum of 12 Nu on the 42nd day post vaccination. CONCLUSIONS: The H2O2 inactivated BVDV vaccine has good safety and immunogenicity, which provides a potential solution for the further development of an efficient and safe BVDV vaccine.


Asunto(s)
Diarrea Mucosa Bovina Viral , Enfermedades de los Bovinos , Virus de la Diarrea Viral Bovina Tipo 1 , Virus de la Diarrea Viral Bovina , Vacunas Virales , Animales , Bovinos , Ratones , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Diarrea/veterinaria , Formaldehído , Peróxido de Hidrógeno , Inmunoglobulina G , Interleucina-4 , Vacunas de Productos Inactivados
10.
Lipids Health Dis ; 23(1): 108, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622571

RESUMEN

BACKGROUND: Surgery is widely regarded as a pivotal therapeutic approach for treating oesophageal cancer, and clinical observations have revealed that many oesophageal cancer patients also present with concomitant hyperlipidaemia. It is surprising that few studies have been performed to determine how blood lipid levels are affected by oesophageal cancer resection. This research was designed to assess the influence of oesophageal cancer resection on lipid profiles among individuals diagnosed with both oesophageal cancer and hyperlipidaemia. METHODS: A retrospective analysis was carried out on 110 patients with hyperlipidaemia and oesophageal cancer who had undergone oesophagectomy at the 900th Hospital of the Joint Logistics Support Force of the Chinese People's Liberation Army. Preoperative and postoperative serological data were collected at seven-, thirty-, sixty-day-, and one-year-long intervals. Changes in lipid levels were compared, the remission of various types of hyperlipidaemia was statistically assessed, and Pearson correlation was used to analyse the association between lipid changes and preoperative body weight. The research sought to assess the reduction in body weight and the proportion of body weight lost one year following surgery. RESULTS: Noteworthy decreases were observed in total cholesterol (TC), triglyceride (TG), and low-density lipoprotein (LDL) levels, with TC decreasing from 6.20 mmol/L to 5.20 mmol/L, TG decreasing from 1.40 mmol/L to 1.20 mmol/L, and LDL decreasing from 4.50 mmol/L to 3.30 mmol/L. Conversely, there was a notable increase in high-density lipoprotein (HDL) levels, which increased from 1.20 mmol/L to 1.40 mmol/L (P < 0.05) compared to the preoperative levels. Notably, the remission rates for mixed hyperlipidaemia (60.9%) and high cholesterol (60.0%) were considerably greater than those for high triglycerides (16.2%). Alterations in TC at one year postoperatively correlated with preoperative weight and weight loss (r = 0.315, -0.216); changes in TG correlated with preoperative weight, percentage of total weight loss (TWL%), and weight reduction (r = -0.295, -0.246, 0.320); and changes in LDL correlated with preoperative weight, TWL%, and weight loss (r = 0.251, 0.186, and -0.207). Changes in non-high-density lipoprotein(non-HDL) were linked to preoperative weight (r = 0.300), and changes in TG/HDL were correlated with preoperative weight and TWL% (r = -0.424, -0.251). CONCLUSIONS: Oesophagectomy significantly improved lipid profiles in oesophageal cancer patients, potentially leading to a reduction in overall cardiovascular risk.


Asunto(s)
Pueblos del Este de Asia , Neoplasias Esofágicas , Hiperlipidemias , Humanos , Estudios Retrospectivos , Colesterol , Esofagectomía , LDL-Colesterol , HDL-Colesterol , Triglicéridos , Lípidos , Neoplasias Esofágicas/complicaciones , Neoplasias Esofágicas/cirugía , Pérdida de Peso , Peso Corporal
11.
Sleep Breath ; 28(3): 1381-1391, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38514588

RESUMEN

PURPOSE: The relationships of sleep factors separately and jointly with metabolic associated fatty liver disease (MAFLD) and significant fibrosis remain unclear. We intended to explore the relationships in the United States. METHODS: This cross-sectional study included 4477 individuals from the National Health and Nutrition Examination Survey from 2017 to 2018. Information regarding each sleep factor (sleep duration, trouble sleeping, snoring, excessive daytime sleep, and sleep apnea symptoms) was obtained through questionnaires. MAFLD was diagnosed by transient elastography according to the consensus definitions. Multivariable logistic regression models were employed to explore relationships of sleep factors separately and jointly with MAFLD and significant fibrosis. RESULTS: Participants having a poor sleep pattern was associated with higher MAFLD and significant fibrosis risk, and poor sleep pattern was related to about threefold (OR, 3.67; 95% CI, 1.82-7.37) increased risk of MAFLD remarkably. When examining specific factors of sleep patterns individually, trouble sleeping (OR, 1.53; 95% CI, 1.10-2.12), snoring (OR, 2.11; 95% CI, 1.40-3.19), excessive daytime sleep (OR, 1.57; 95% CI, 0.93-2.62), and sleep apnea symptoms (OR, 1.87; 95% CI, 1.13-3.10) were positively associated with the odds of MAFLD (all P < 0.05). However, sleep duration was not independently correlated with MAFLD or significant fibrosis. Sleep patterns showed similar relationships with MAFLD, regardless of all age, sex, physical activity, and shift work groups. CONCLUSIONS: Poor sleep pattern was linked with a considerably higher risk of MAFLD and significant fibrosis.


Asunto(s)
Cirrosis Hepática , Humanos , Masculino , Femenino , Estudios Transversales , Persona de Mediana Edad , Adulto , Cirrosis Hepática/epidemiología , Estados Unidos/epidemiología , Factores de Riesgo , Encuestas Nutricionales , Trastornos del Sueño-Vigilia/epidemiología , Ronquido/epidemiología , Síndromes de la Apnea del Sueño/epidemiología , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/complicaciones , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Anciano
12.
J Exp Child Psychol ; 241: 105843, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38271850

RESUMEN

This research, comprising three preregistered studies, investigated the link between self-efficacy and cheating on an academic test in 5- and 6-year-old children. Study 1 assessed children's general self-efficacy and found it to be unrelated to their cheating behavior. Study 2 assessed task-specific self-efficacy, which was not found to be associated with cheating. In Study 3, children were randomly assigned to either an experimental group, which received brief positive feedback on task-specific self-efficacy, or a control group, which received no feedback. The experimental group demonstrated significantly less cheating. These findings, for the first time, identify a specific connection between young children's self-efficacy and academic dishonesty and suggest that positive feedback on task-specific efficacy could be a simple effective strategy for fostering academic integrity early on.


Asunto(s)
Decepción , Autoeficacia , Niño , Humanos , Preescolar
13.
BMC Geriatr ; 24(1): 468, 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811863

RESUMEN

BACKGROUND: Oral frailty is reported to increase the risk of new onset of mild cognitive impairment. Whereas, the association of oral frailty with cognition among older adults in both physical frail and non-physical frail status has not been sufficiently explored, and whether there are sex differences in the association is unclear. This study investigated the association of oral frailty and physical frailty with global cognitive function and executive function among older adults, as well as the sex differences in such association. METHODS: This cross-sectional study included 307 participants aged ≥ 60 years old from communities between June 2023 and August 2023, in Nanjing, China. Global cognitive function and executive function were assessed by using the Montreal Cognitive Assessment (MoCA) and Trail Making Tests A (TMT-A), respectively. Oral frailty was identified by the combination of natural tooth, Oral Frailty Index-8 (OFI-8), and oral diadochokinesis. Physical frailty was measured by using Fried phenotype model which contained 5 criteria: unintentional weight loss, weakness, exhaustion, slowness, and low physical activity. Multiple linear regression analyses for overall participants and stratified by sex and presence or absence of physical frailty were performed, respectively, to examine the association between oral frailty and cognitive functions. RESULTS: The median age of participants was 70 years old. The study included 158 (51.5%) females, 53 (17.3%) individuals with physical frailty, and 65 (21.2%) participants with oral frailty. After adjustment, the association between oral frailty and global cognitive function was observed in the physical frailty group (B = -2.67, 95% Confidence Interval [CI]: -5.27 to -0.07, p = 0.045) and the females with physical frailty (B = -4, 95% CI: -7.41 to -0.58, p = 0.024). Oral frailty was associated with executive function in overall participants (B = 0.12, 95% CI: 0.01 to 0.22, p = 0.037), physical frailty group (B = 23.68, 95% CI: 1.37 to 45.99, p = 0.038). In the adjusted models, oral frailty was significantly associated with executive function in all females (B = 0.21, 95% CI: 0.05 to 0.36, p = 0.009), in females without physical frailty (B = 0.19, 95% CI: 0.02 to 0.36, p = 0.027), and in females with physical frailty (B = 48.69, 95% CI: 7.17 to 90.21, p = 0.024). CONCLUSIONS: Physical frailty intensifies the positive association of oral frailty with poor global cognitive function and executive function among older adults, particularly among females. It is ponderable to consider sex differences and facilitate the management of physical frailty when it comes to promoting cognitive health based on the perspective of oral health among older adults.


Asunto(s)
Disfunción Cognitiva , Función Ejecutiva , Anciano Frágil , Fragilidad , Humanos , Femenino , Anciano , Estudios Transversales , Masculino , Fragilidad/epidemiología , Fragilidad/psicología , Fragilidad/diagnóstico , Función Ejecutiva/fisiología , Anciano Frágil/psicología , Disfunción Cognitiva/epidemiología , Disfunción Cognitiva/psicología , Disfunción Cognitiva/diagnóstico , Anciano de 80 o más Años , Persona de Mediana Edad , Factores Sexuales , China/epidemiología , Evaluación Geriátrica/métodos , Cognición/fisiología
14.
Molecules ; 29(12)2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38931007

RESUMEN

A novel coordination polymer [Zn(atyha)2]n (1) (Hatyha = 2-(2-aminothiazole-4-yl)-2- hydroxyiminoacetic acid) was constructed by hydrothermal reaction of Zn2+ with Hatyha ligand. CP 1 exhibits a 2D (4,4)-connected topological framework with Schläfli symbol of {44·62}, where atyha- anions serve as tridentate ligands, bridging with Zn2+ through carboxylate, thiazole and oxime groups. CP 1 displays a strong ligand-based photoluminescence at 390 nm in the solid state, and remains significantly structurally stable in water. Interestingly, it can be utilized as a fluorescent probe for selective and sensitive sensing of Fe3+, Cr2O72- and MnO4- through the fluorescent turn-off effect with limit of detection (LOD) of 3.66 × 10-6, 2.38 × 10-5 and 2.94 × 10-6 M, respectively. Moreover, the efficient recyclability for detection of Fe3+ and Cr2O72- is better than that for MnO4-. The mechanisms of fluorescent quenching involve reversible overlap of UV-Vis absorption bands of the analytes (Fe3+, Cr2O72- and MnO4-) with fluorescence excitation and emission bands for CP 1, respectively.

15.
Angew Chem Int Ed Engl ; : e202410397, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38896110

RESUMEN

The valorization of native lignin to functionalized aromatic compounds under visible light is appealing yet challenging. In this communication, colloidal mercaptoalkanoic acid capped ultrathin ZnIn2S4 (ZIS) microbelts was successfully fabricated, which was used as a superior catalyst for depolymerization of native lignin in birch woodmeal under visible light, with an optimum yield of 28.8 wt% to functionalized aromatic monomers achieved in 8 h. The capped mercaptoalkanoic acid not only enables a solvent modulated reversible interchange of ZIS between the colloidal state for efficient reaction and the aggregated state for facile separation, but also serves as a precursor for light initiated generation of reactive thiyl radical for highly selective cleavage of ß-O-4 bond in native lignin. This work provides a green and efficient strategy for the depolymerization of native lignin to functionalized aromatic monomers under mild conditions, which involves a new mechanism for the cleavage of ß-O-4 bonds in native lignin. The capability of cleavage of ß-O-4 bonds in native lignin by photogenerated thiyl radicals also demonstrates the great potential of using photogenerated thiyl radicals in organics transformations.

16.
Angew Chem Int Ed Engl ; 63(23): e202403156, 2024 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-38566540

RESUMEN

Among the intriguing bicontinuous self-assembled structures, the gyroid cubic is the most ubiquitous. It is found in block and star polymers, surfactants with or without solvent, in thermotropic liquid crystals with end- or side-chains, and in biosystems providing structural color and modelling cell mitosis. It contains two interpenetrating networks of opposite chirality and is thus achiral if, as usual, the content of the two nets is the same. However, we now find that this is not the case for strongly chiral compounds. While achiral molecules follow the opposite twists of nets 1 and 2, molecules with a chiral center in their rod-like core fail to follow the 70° twist between junctions in net 2 and instead wind against it by -110° to still match the junction orientation. The metastable chiral gyroid is a high-entropy high-heat-capacity mesophase. The homochirality of its nets makes the CD signal of the thienofluorenone compounds close to that in the stable I23 phase with 3 isochiral nets.

17.
J Am Chem Soc ; 145(31): 17443-17460, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37523689

RESUMEN

The recently discovered orthorhombic liquid crystal (LC) phase of symmetry Fddd is proving to be widespread. In this work, a chiral hydroxybutyrate linkage is inserted into the molecular core of hexacatenar rodlike compounds, containing a thienylfluorenone fluorophore. In addition to more usual tools, the methods used include grazing-incidence X-ray scattering, modulated differential scanning calorimetry (DSC), flash DSC with rates up to 6000 K/s, and chiro-optical spectroscopies using Mueller matrix method, plus conformational mapping. Although pure R and S enantiomers form only a strongly chiral hexagonal columnar LC phase (Colh*), the racemic mixture forms a highly ordered Fddd phase with 4 right- and 4 left-handed twisted ribbon-like columns traversing its large unit cell. In that structure, the two enantiomers locally deracemize and self-sort into the columns of their preferred chirality. The twisted ribbons in Fddd, with a 7.54 nm pitch, consist of stacked rafts, each containing ∼2 side-by-side molecules, the successive rafts rotated by 17°. In contrast, an analogous achiral compound forms only the columnar phase. The multiple methods used gave a comprehensive picture and helped in-depth understanding not only of the Fddd phase but also of the "parachiral" Colh* in pure enantiomers with irregular helicity, whose chirality is compared to the magnetization of a paramagnet in a field. Unusual short-range ordering effects are also described. An explanation of these phenomena is proposed based on conformational analysis. Surprisingly, the isotropic-columnar transition is extremely fast, completing within ∼20 ms. A clear effect of phase on UV-vis absorption and emission is observed.

18.
Biochem Biophys Res Commun ; 653: 153-160, 2023 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-36870240

RESUMEN

Congenital anomalies of the kidney and urinary tract (CAKUT) have been attributed to genetic and environmental factors. However, monogenic and copy number variations cannot sufficiently explain the cause of the majority of CAKUT cases. Multiple genes through various modes of inheritance may lead to CAKUT pathogenesis. We previously showed that Robo2 and Gen1 coregulated the germination of ureteral buds (UB), significantly increasing CAKUT incidence. Furthermore, MAPK/ERK pathway activation is the central mechanism of these two genes. Thus, we explored the effect of the MAPK/ERK inhibitor U0126 in the CAKUT phenotype in Robo2PB/+Gen1PB/+ mice. Intraperitoneal injection of U0126 during pregnancy prevented the development of the CAKUT phenotype in Robo2PB/+Gen1PB/+ mice. Additionally, a single dose of 30 mg/kg U0126 on day 10.5 embryos (E10.5) was most effective for reducing CAKUT incidence and ectopic UB outgrowth in Robo2PB/+Gen1PB/+ mice. Furthermore, embryonic kidney mesenchymal levels of p-ERK were significantly decreased on day E11.5 after U0126 treatment, along with decreased cell proliferation index PHH3 and ETV5 expression. Collectively, Gen1 and Robo2 exacerbated the CAKUT phenotype in Robo2PB/+Gen1PB/+ mice through the MAPK/ERK pathway, increasing proliferation and ectopic UB outgrowth.


Asunto(s)
Obstrucción Ureteral , Sistema Urinario , Ratones , Animales , Sistema de Señalización de MAP Quinasas , Variaciones en el Número de Copia de ADN , Riñón/metabolismo , Sistema Urinario/anomalías , Obstrucción Ureteral/metabolismo , Receptores Inmunológicos/genética , Receptores Inmunológicos/metabolismo , Resolvasas de Unión Holliday/metabolismo
19.
Small ; 19(36): e2206919, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37183293

RESUMEN

The regeneration of diabetic bone defects remains challenging. Hyperglycemia causes inflammation state and excessive reactive oxygen species (ROS) during bone regeneration period. These two effects reinforce one another and create an endless loop that is also accompanied by mitochondrial dysfunction. However, there is still no effective and inclusive method targeting at the two aspects and breaking the vicious cycle. Herein, nanoparticles-Met@ZIF-8(metformin loaded zeolitic imidazolate frameworks) modified hydrogel that is capable of releasing metformin and Zn elements are constructed. This hydrogel treats hyperglycemia while also controlling mitochondrial function, reducing inflammation, and restoring homeostasis. In addition, the synergetic effect from metformin and Zn ions inhibits ROS-inflammation cascade generation and destroys the continuous progress by taking effects in both ROS and inflammation and further keeping organelles' homeostasis. Furthermore, with the recovery of mitochondria and breakdown of the ROS-inflammation cascade cycle, osteogenesis under a diabetic microenvironment is enhanced in vivo and in vitro. In conclusion, the study provides critical insight into the biological mechanism and potential therapy for diabetic bone regeneration.


Asunto(s)
Diabetes Mellitus , Hiperglucemia , Estructuras Metalorgánicas , Humanos , Especies Reactivas de Oxígeno/metabolismo , Hidrogeles
20.
Small ; 19(44): e2301721, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37386796

RESUMEN

Heterogenous catalysis is important for future clean and sustainable energy systems. However, an urgent need to promote the development of efficient and stable hydrogen evolution catalysts still exists. In this study, ruthenium nanoparticles (Ru NPs) are in situ grown on Fe5 Ni4 S8 support (Ru/FNS) by replacement growth strategy. An efficient Ru/FNS electrocatalyst with enhanced interfacial effect is then developed and successfully applied for pH-universal hydrogen evolution reaction (HER). The Fe vacancies formed by FNS during the electrochemical process are found to be conducive to the introduction and firm anchoring of Ru atoms. Compared to Pt atoms, Ru atoms get easily aggregated and then grow rapidly to form NPs. This induces more bonding between Ru NPs and FNS, preventing the fall-off of Ru NPs and maintaining the structural stability of FNS. Moreover, the interaction between FNS and Ru NPs can adjust the d-band center of Ru NPs, as well as balance the hydrolytic dissociation energy and hydrogen binding energy. Consequently, the as-prepared Ru/FNS electrocatalyst exhibits excellent HER activity and improved cycle stability under pH-universal conditions. The developed pentlandite-based electrocatalysts with low cost, high activity, and good stability are promising candidates for future applications in water electrolysis.

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