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1.
Nature ; 621(7979): 487-492, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37385423

RESUMO

The Berry curvature and quantum metric are the imaginary part and real part, respectively, of the quantum geometric tensor, which characterizes the topology of quantum states1. The Berry curvature is known to generate a number of important transport phenomena, such as the quantum Hall effect and the anomalous Hall effect2,3; however, the consequences of the quantum metric have rarely been probed by transport measurements. Here we report the observation of quantum-metric-induced nonlinear transport, including both a nonlinear anomalous Hall effect and a diode-like non-reciprocal longitudinal response, in thin films of a topological antiferromagnet, MnBi2Te4. Our observations reveal that the transverse and longitudinal nonlinear conductivities reverse signs when reversing the antiferromagnetic order, diminish above the Néel temperature and are insensitive to disorder scattering, thus verifying their origin in the band-structure topology. They also flip signs between electron- and hole-doped regions, in agreement with theoretical calculations. Our work provides a means to probe the quantum metric through nonlinear transport and to design magnetic nonlinear devices.

2.
Circ Res ; 135(6): 651-667, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39082138

RESUMO

BACKGROUND: ß-adrenergic receptor (ß-AR) overactivation is a major pathological cue associated with cardiac injury and diseases. AMPK (AMP-activated protein kinase), a conserved energy sensor, regulates energy metabolism and is cardioprotective. However, whether AMPK exerts cardioprotective effects via regulating the signaling pathway downstream of ß-AR remains unclear. METHODS: Using immunoprecipitation, mass spectrometry, site-specific mutation, in vitro kinase assay, and in vivo animal studies, we determined whether AMPK phosphorylates ß-arrestin-1 at serine (Ser) 330. Wild-type mice and mice with site-specific mutagenesis (S330A knock-in [KI]/S330D KI) were subcutaneously injected with the ß-AR agonist isoproterenol (5 mg/kg) to evaluate the causality between ß-adrenergic insult and ß-arrestin-1 Ser330 phosphorylation. Cardiac transcriptomics was used to identify changes in gene expression from ß-arrestin-1-S330A/S330D mutation and ß-adrenergic insult. RESULTS: Metformin could decrease cAMP/PKA (protein kinase A) signaling induced by isoproterenol. AMPK bound to ß-arrestin-1 and phosphorylated Ser330 with the highest phosphorylated mass spectrometry score. AMPK activation promoted ß-arrestin-1 Ser330 phosphorylation in vitro and in vivo. Neonatal mouse cardiomyocytes overexpressing ß-arrestin-1-S330D (active form) inhibited the ß-AR/cAMP/PKA axis by increasing PDE (phosphodiesterase) 4 expression and activity. Cardiac transcriptomics revealed that the differentially expressed genes between isoproterenol-treated S330A KI and S330D KI mice were mainly involved in immune processes and inflammatory response. ß-arrestin-1 Ser330 phosphorylation inhibited isoproterenol-induced reactive oxygen species production and NLRP3 (NOD-like receptor protein 3) inflammasome activation in neonatal mouse cardiomyocytes. In S330D KI mice, the ß-AR-activated cAMP/PKA pathways were attenuated, leading to repressed inflammasome activation, reduced expression of proinflammatory cytokines, and mitigated macrophage infiltration. Compared with S330A KI mice, S330D KI mice showed diminished cardiac fibrosis and improved cardiac function upon isoproterenol exposure. However, the cardiac protection exerted by AMPK was abolished in S330A KI mice. CONCLUSIONS: AMPK phosphorylation of ß-arrestin-1 Ser330 potentiated PDE4 expression and activity, thereby inhibiting ß-AR/cAMP/PKA activation. Subsequently, ß-arrestin-1 Ser330 phosphorylation blocks ß-AR-induced cardiac inflammasome activation and remodeling.


Assuntos
Proteínas Quinases Ativadas por AMP , Isoproterenol , Miócitos Cardíacos , beta-Arrestina 1 , Animais , Fosforilação , beta-Arrestina 1/metabolismo , beta-Arrestina 1/genética , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Isoproterenol/toxicidade , Isoproterenol/farmacologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Camundongos Endogâmicos C57BL , Masculino , Receptores Adrenérgicos beta/metabolismo , Serina/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Agonistas Adrenérgicos beta/toxicidade , Células Cultivadas , Transdução de Sinais , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/genética , Humanos
3.
BMC Plant Biol ; 24(1): 507, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844853

RESUMO

BACKGROUND: Powdery mildew, caused by Eeysiphe heraclei, seriously threatens Heracleum moellendorffii Hance. Plant secondary metabolites are essential to many activities and are necessary for defense against biotic stress. In order to clarify the functions of these metabolites in response to the pathogen, our work concentrated on the variations in the accumulation of secondary metabolites in H. moellendorffii during E. heraclei infection. RESULTS: Following E. heraclei infection, a significant upregulation of coumarin metabolites-particularly simple coumarins and associated genes was detected by RNA-seq and UPLC-MS/MS association analysis. Identifying HmF6'H1, a Feruloyl CoA 6'-hydroxylase pivotal in the biosynthesis of the coumarin basic skeleton through ortho-hydroxylation, was a significant outcome. The cytoplasmic HmF6'H1 protein was shown to be able to catalyze the ortho-hydroxylation of p-coumaroyl-CoA and caffeoyl-CoA, resulting in the formation of umbelliferone and esculetin, respectively. Over-expression of the HmF6'H1 gene resulted in increased levels of simple coumarins, inhibiting the biosynthesis of furanocoumarins and pyranocoumarins by suppressing PT gene expression, enhancing H. moellendorffii resistance to powdery mildew. CONCLUSIONS: These results established HmF6'H1 as a resistance gene aiding H. moellendorffii in combatting E. heraclei infection, offering additional evidence of feruloyl-CoA 6'-hydroxylase role in catalyzing various types of simple coumarins. Therefore, this work contributes to our understanding of the function of simple coumarins in plants' defense against powdery mildew infection.


Assuntos
Ascomicetos , Cumarínicos , Metaboloma , Doenças das Plantas , Transcriptoma , Apiaceae/genética , Apiaceae/metabolismo , Apiaceae/microbiologia , Ascomicetos/fisiologia , Cumarínicos/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Heracleum/genética , Heracleum/metabolismo , Heracleum/microbiologia
4.
Opt Express ; 32(7): 11573-11582, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571001

RESUMO

Self-powered deep ultraviolet photodetectors (DUV PDs) are essential in environmental monitoring, flame detection, missile guidance, aerospace, and other fields. A heterojunction photodetector based on p-CuI/n-ZnGa2O4 has been fabricated by pulsed laser deposition combined with vacuum thermal evaporation. Under 260 nm DUV light irradiation, the photodetector exhibits apparent self-powered performance with a maximum responsivity and specific detectivity of 2.75 mA/W and 1.10 × 1011 Jones at 0 V. The photodetector exhibits high repeatability and stability under 260 nm periodic illumination. The response and recovery time are 205 ms and 133 ms, respectively. This work provides an effective strategy for fabricating high-performance self-powered DUV photodetectors.

5.
Opt Express ; 32(6): 9227-9236, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571161

RESUMO

Ultraviolet (UV) photodetector plays an important role in military, civilian and people's daily life, and is an indispensable part of spectral detection. However, photodetectors target at the UVB region (280-320 nm) are rarely reported, and the devices detected by medium-wave UV light generally have problems such as low detection rate, low sensitivity, and poor stability, which are difficult to meet the market application needs. Herein, Cs-Cu-I films with mixed-phase have been prepared by vacuum thermal evaporation. By adjusting the proportion of evaporation sources (CsI and CuI), the optical bandgaps of mixed-phase Cs-Cu-I films can be tuned between 3.7 eV and 4.1 eV. This absorption cut-off edge is exactly at both ends of the UVB band, which indicating its potential application in the field of UVB detection. Finally, the photodetectors based on Cs-Cu-I/n-Si heterojunction are fabricated. The photodetector shows good spectral selectivity for UVB band, and has a photoresponsivity of 22 mA/W, a specific detectivity of 1.83*1011 Jones, an EQE over 8.7% and an on/off ratio above 20.

6.
Opt Lett ; 49(9): 2309-2312, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691706

RESUMO

Zinc gallium oxide (ZnGa2O4) has attracted considerable interest in deep-ultraviolet photodetectors, due to the ultrawide bandgap, high transmittance in the ultraviolet (UV) region, and excellent environmental stability. In this study, ZnGa2O4 thin films were deposited on p-GaN epi-layers using pulsed laser deposition, resulting in improved crystalline quality. The ZnGa2O4 film exhibited a bandgap of 4.93 eV, calculated through absorption spectra. A heterojunction photodetector (PD) was constructed, demonstrating a rectification effect, an on/off ratio of 12,697 at -5.87 V, a peak responsivity of 14.5 mA/W, and a peak detectivity of 1.14 × 1012 Jones (262 nm, -6 V). The PD exhibited a fast response time (39 ms) and recovery time (30 ms) under 262 nm illumination. The band diagram based on the Anderson model elucidates the photoresponse and carrier transport mechanism. This work paves the way for advancing next-generation optoelectronics.

7.
Environ Sci Technol ; 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39402705

RESUMO

Urban landscapes are high phosphorus (P) consumption areas and consequently generate substantial P-containing urban solid waste (domestic kitchen wastes, animal bones, and municipal sludge), due to large population. However, urbanization can also trap P through cultivated land loss and urban solid waste disposal. Trapped urban P is an overlooked and inaccessible P stock. Here, we studied how urbanization contributes to trapped urban P and how it affects the P cycle. We take China as a case study. Our results showed that China generated a total of 13 (±0.9) Tg urban trapped P between 1992-2019. This amounts to 6 (±0.5) % of the total consumed P and 9 (±0.6) % of the chemical fertilizer P used in China over that period. The loss of cultivated land accounted for 15% of the trapped urban P, and half of this was concentrated in three provinces: Shandong, Henan, and Hebei. This is primarily since nearly one-third of the newly expanded urban areas are located within these provinces. The remaining 85% of trapped urban P was associated with urban solid waste disposal. Our findings call for more actions to preserve fertile cultivated land and promote P recovery from urban solid waste through sound waste classification and recycling systems to minimize P trapped in urban areas.

8.
Bioorg Chem ; 143: 107097, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38190797

RESUMO

To discover new photosensitizers with long wavelength UV-visible absorption, high efficiency, and low side effects for photodynamic therapy, here, a series of novel thieno[3,2-b]thiophene-fused BODIPY derivatives were designed, synthesized and characterized. These compounds had a distinct absorption band at 640-680 nm, fluorescence emission at 650-760 nm, and good solubility with anti-aggregation effects. These new compounds possessed obvious singlet oxygen generation ability and photodynamic anti-Eca-109 cancer cells activities in vitro. Among them, compound II4 could be well uptaked by Eca-109 cells, and result in the apoptosis after laser irradiation, and have outstanding photodynamic efficiency both in vitro and in vivo. Therefore, II4 could be considered as a potential photosensitizer drug candidate for PDT and photo-imaging.


Assuntos
Compostos de Boro , Fotoquimioterapia , Fotoquimioterapia/métodos , Solubilidade , Tiofenos/farmacologia , Fármacos Fotossensibilizantes/farmacologia
9.
Nature ; 555(7696): 363-366, 2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29513654

RESUMO

Sustainably feeding a growing population is a grand challenge, and one that is particularly difficult in regions that are dominated by smallholder farming. Despite local successes, mobilizing vast smallholder communities with science- and evidence-based management practices to simultaneously address production and pollution problems has been infeasible. Here we report the outcome of concerted efforts in engaging millions of Chinese smallholder farmers to adopt enhanced management practices for greater yield and environmental performance. First, we conducted field trials across China's major agroecological zones to develop locally applicable recommendations using a comprehensive decision-support program. Engaging farmers to adopt those recommendations involved the collaboration of a core network of 1,152 researchers with numerous extension agents and agribusiness personnel. From 2005 to 2015, about 20.9 million farmers in 452 counties adopted enhanced management practices in fields with a total of 37.7 million cumulative hectares over the years. Average yields (maize, rice and wheat) increased by 10.8-11.5%, generating a net grain output of 33 million tonnes (Mt). At the same time, application of nitrogen decreased by 14.7-18.1%, saving 1.2 Mt of nitrogen fertilizers. The increased grain output and decreased nitrogen fertilizer use were equivalent to US$12.2 billion. Estimated reactive nitrogen losses averaged 4.5-4.7 kg nitrogen per Megagram (Mg) with the intervention compared to 6.0-6.4 kg nitrogen per Mg without. Greenhouse gas emissions were 328 kg, 812 kg and 434 kg CO2 equivalent per Mg of maize, rice and wheat produced, respectively, compared to 422 kg, 941 kg and 549 kg CO2 equivalent per Mg without the intervention. On the basis of a large-scale survey (8.6 million farmer participants) and scenario analyses, we further demonstrate the potential impacts of implementing the enhanced management practices on China's food security and sustainability outlook.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais , Produtos Agrícolas/crescimento & desenvolvimento , Eficiência Organizacional , Fazendeiros , China , Técnicas de Apoio para a Decisão , Grão Comestível/crescimento & desenvolvimento , Política Ambiental , Fertilizantes/estatística & dados numéricos , Abastecimento de Alimentos/métodos , Efeito Estufa , Nitrogênio/metabolismo , Oryza/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento
10.
Clin Exp Nephrol ; 28(7): 683-691, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38457031

RESUMO

BACKGROUND: Cardiovascular death is the main cause of death in patients with end-stage kidney disease (ESKD). Left ventricular hypertrophy (LVH) and left atrial diameter (LAD) enlargement are frequent cardiac alterations in patients with ESKD and are major risk factors for cardiovascular events. However, it remains unclear whether there is an association between combined LAD or LVH and all-cause or cardiovascular mortality in this population. METHODS: A single-centre, retrospective cohort study including 576 haemodialysis (HD) patients was conducted. Patients were evaluated by cardiac ultrasound, and the study cohort was divided into four groups according to LAD and LVH status: low LAD and non-LVH; low LAD and LVH; high LAD and non-LVH; and high LAD and LVH. We used Kaplan-Meier analysis and Cox proportional hazard regression to analyse all-cause and cardiovascular mortality after multivariate adjustment. RESULTS: LAD was associated with an increased risk of all-cause mortality (HR 2.371, 1.602-3.509; p < 0.001). No significant differences were found between LVH and the risk of all-cause mortality. Patients with high LAD and LVH had significantly greater all-cause and cardiovascular mortality than did those with low LAD and non-LVH after adjustments for numerous potential confounders (HR 3.080, 1.608-5.899; p = 0.001) (HR 4.059, 1.753-9.397; p = 0.001). CONCLUSION: Among maintenance haemodialysis (MHD) patients, LAD was more strongly associated with mortality than was LVH. A high LAD and LVH are associated with a greater risk of mortality. Our results emphasize that the occurrence of LAD and LVH in combination provides information that may be helpful in stratifying the risk of MHD patients.


Assuntos
Átrios do Coração , Hipertrofia Ventricular Esquerda , Falência Renal Crônica , Diálise Renal , Humanos , Estudos Retrospectivos , Hipertrofia Ventricular Esquerda/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/mortalidade , Diálise Renal/efeitos adversos , Diálise Renal/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Átrios do Coração/diagnóstico por imagem , Átrios do Coração/patologia , Falência Renal Crônica/terapia , Falência Renal Crônica/mortalidade , Falência Renal Crônica/complicações , Estimativa de Kaplan-Meier , Fatores de Risco , Modelos de Riscos Proporcionais , Causas de Morte , Medição de Risco , Ecocardiografia
11.
Ren Fail ; 46(1): 2338217, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38584147

RESUMO

BACKGROUND: Elderly hemodialysis (HD) patients have a high risk of death. The effect of different types of HD membranes on survival is still controversial. The purpose of this study was to determine the relationship between the use of low-flux or high-flux membranes and all-cause and cardiovascular mortality in elderly hemodialysis patients. METHODS: This was a retrospective clinical study involving maintenance hemodialysis patients which were categorized into low-flux and high-flux groups according to the dialyzer they were using. Propensity score matching was used to balance the baseline data of the two groups. Survival rates were compared between the two groups, and the risk factors for death were analyzed by multivariate Cox regression. RESULTS: Kaplan-Meier survival analysis revealed no significant difference in all-cause mortality between the low-flux group and the high-flux group (log-rank test, p = 0.559). Cardiovascular mortality was significantly greater in the low-flux group than in the high-flux group (log-rank test, p = 0.049). After adjustment through three different multivariate models, we detected no significant difference in all-cause mortality. Patients in the high-flux group had a lower risk of cardiovascular death than did those in the low-flux group (HR = 0.79, 95% CI, 0.54-1.16, p = 0.222; HR = 0.58, 95% CI, 0.37-0.91, p = 0.019). CONCLUSIONS: High-flux hemodialysis was associated with a lower relative risk of cardiovascular mortality in elderly MHD patients. High-flux hemodialysis did not improve all-cause mortality rate. Differences in urea distribution volume, blood flow, and systemic differences in solute clearance by dialyzers were not further analyzed, which are the limitations of this study.


Assuntos
Doenças Cardiovasculares , Falência Renal Crônica , Humanos , Idoso , Falência Renal Crônica/complicações , Estudos Retrospectivos , Membranas Artificiais , Diálise Renal/efeitos adversos
12.
Heart Lung Circ ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39394030

RESUMO

AIM: To report the safety and effectiveness of a modified Warden procedure. METHOD: Twenty-six (26) patients underwent modified Warden surgery at our centre from September 2017 to September 2021. In all patients, the superior vena cava (SVC) was reconstructed by turning the atrial wall in the main body of the right atrium upwards and applying fresh autologous pericardial patches. There were 13 male patients and 13 female patients, and the median age of the patients was 7.0 (range, 0.3-47.0) years. The median follow-up time after surgery was 47.0 (range, 32.0-80.0) months. RESULTS: The aortic cross-clamp time was 108.50±34.72 minutes, the cardiopulmonary bypass time was 154.81±41.65 minutes, the median postoperative mechanical ventilation time was 8.5 (range, 0.0-91.0) hours, the median intensive care unit stay was 43.5 (range, 15.0-352.0) hours, and the median length of postoperative hospital stay was 7.0 (range, 6.0-19.0) days. All patients were safely and successfully discharged from the hospital. No deaths or sinus node dysfunction occurred during the follow-up period. The mean gradient of the reconstructed SVC and/or the right pulmonary vein (PV) increased in eight patients and decreased to less than 1 mmHg in six patients. One (1) adult patient had already undergone two vascular interventions, and one child had persistent stenosis but did not undergo reoperation at the time of the study. In addition, two patients were subjected to pericardial windowing. CONCLUSIONS: A modified Warden technique using a right atrial flap and autologous pericardium effectively corrected the high-plane connection between the PVs and SVC. This technique effectively avoids sinus node dysfunction; however, a short-term increase in the differential pressure of the re-established SVC or PV after the procedure is acceptable, and reintervention is required only in rare cases.

13.
Angew Chem Int Ed Engl ; 63(24): e202402684, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38597346

RESUMO

Electrocatalytic urea synthesis under ambient conditions offers a promising alternative strategy to the traditional energy-intensive urea industry protocol. Limited by the electrostatic interaction, the reduction reaction of anions at the cathode in the electrocatalytic system is not easily achievable. Here, we propose a novel strategy to overcome electrostatic interaction via pulsed electroreduction. We found that the reconstruction-resistant CuSiOx nanotube, with abundant atomic Cu-O-Si interfacial sites, exhibits ultrastability in the electrosynthesis of urea from nitrate and CO2. Under a pulsed potential approach with optimal operating conditions, the Cu-O-Si interfaces achieve a superior urea production rate (1606.1 µg h-1 mgcat. -1) with high selectivity (79.01 %) and stability (the Faradaic efficiency is retained at 80 % even after 80 h of testing), outperforming most reported electrocatalytic synthesis urea catalysts. We believe our strategy will incite further investigation into pulsed electroreduction increasing substrate transport, which may guide the design of ambient urea electrosynthesis and other energy conversion systems.

14.
Small ; 19(14): e2207581, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36651007

RESUMO

Overall photocatalytic conversion of CO2 and pure H2 O driven by solar irradiation into methanol provides a sustainable approach for extraterrestrial synthesis. However, few photocatalysts exhibit efficient production of CH3 OH. Here, BiOBr nanosheets supporting atomic Cu catalysts for CO2 reduction are reported. The investigation of charge dynamics demonstrates a strong built-in electric field established by isolated Cu sites as electron traps to facilitate charge transfer and stabilize charge carriers. As result, the catalysts exhibit a substantially high catalytic performance with methanol productivity of 627.66 µmol gcatal -1 h-1 and selectivity of ≈90% with an apparent quantum efficiency of 12.23%. Mechanism studies reveal that the high selectivity of methanol can be ascribed to energy-favorable hydrogenation of *CO intermediate giving rise to *CHO. The unfavorable adsorption on Cu1 @BiOBr prevents methanol from being oxidized by photogenerated holes. This work highlights the great potential of single-atom photocatalysts in chemical transformation and energy storage reactions.

15.
BMC Microbiol ; 23(1): 102, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-37060052

RESUMO

BACKGROUND: Many studies reported the association between gut microbiota and type 2 diabetes mellitus (T2D), but it is still unclear which bacterial genus plays a key role and how the metabolic function of gut microbiota changes in the occurrence and development of T2D. Besides, there is a high diabetic prevalence in Mongolian population, which may be partly affected by their high calorie diet. This study identified the main bacterial genus influencing T2D in Mongolian population, and analyzed the changes of metabolic function of gut microbiome. The association between dietary factors and the relative abundance of main bacterial genus and its metabolic function was also studied. METHODS: Dietary surveys and gut microbiota test were performed on 24 Mongolian volunteers that were divided into T2D (6 cases), PRET2D (6 cases) and Control group (12 cases) according to fasting plasma glucose (FPG) values. The relative abundance and metabolic function of gut microbiome from their fecal samples were measured by metagenomic analysis. Statistic method was used to evaluate the association between dietary factors and the relative abundance of the main bacterial genus or its metabolic function. RESULTS: This study found that the Clostridium genus may be one of the key bacterial genera affecting the process of T2D. First, the relative abundance of Clostridium genus was significantly different among the three groups. Second, there was a higher relative abundance of metabolic enzymes of gut bacteria in PRET2D and T2D group than that in Control group. Third, a strong correlation between Clostridium genus and many metabolic enzymes was uncovered, many of which may be produced by the Clostridium. Last, carotene intake daily was negatively correlated with the Clostridium but positively correlated with tagaturonate reductase catalyzing interconversions of pentose and glucuronate. CONCLUSIONS: The gut Clostridium genus may play an important role in the development of T2D and it could be a potential biomarker for T2D in Mongolian population. Meanwhile, the metabolic function of gut bacteria has changed during the early stage of T2D and the changes in carbohydrate, amino acid, lipid or energy metabolism of Clostridium genus may play a critical role. In addition, the carotene intake may affect reproduction and metabolic function of Clostridium genus.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Humanos , Glicemia , Dieta , Bactérias/genética , Jejum
16.
Cardiovasc Diabetol ; 22(1): 63, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36944934

RESUMO

BACKGROUND: It is now understood that stress hyperglycemia is associated with adverse outcomes in hospitalized patients. Herein, we aimed to investigate the association between stress hyperglycemia and mortality risk in acute coronary syndrome (ACS) patients who underwent percutaneous coronary intervention (PCI). METHODS: This cohort study comprised 5190 ACS patients who underwent PCI from the Cardiovascular Center Beijing Friendship Hospital Database Bank (CBDBANK) from January 2013 to January 2021. Stress hyperglycemia was defined by the glucose/glycated albumin (GA) ratio, calculated as admission fasting plasma glucose divided by GA. The patients were divided into four groups according to glucose/GA ratio quartiles (Q1-Q4). Cox proportional hazards regression and restricted cubic spline were used to evaluate the association between glucose/GA ratio and all-cause and cardiovascular mortality. RESULTS: During a median follow-up of 4.0 years, the number of all-cause deaths was 313 (6.0%) and cardiovascular-associated deaths was 177 (3.4%). After adjustment for potential confounders, the risk of all-cause mortality increased in the lowest (HR, 1.43; 95% CI, 1.01-2.03) and highest (HR, 1.51; 95% CI, 1.03-2.21) glucose/GA ratio quartiles compared to Q2. The restricted cubic splines showed that the association between glucose/GA ratio and all-cause mortality was U-shaped after full adjustment (P nonlinear = 0.008). Similar results were observed for cardiovascular mortality. In subgroup analyses according to diabetes status, the U-shaped relationship was only significant in patients with diabetes mellitus. CONCLUSION: In ACS patients undergoing PCI, low and high glucose/GA ratio values were associated with an increased all-cause and cardiovascular mortality, especially in those with diabetes mellitus.


Assuntos
Síndrome Coronariana Aguda , Diabetes Mellitus , Hiperglicemia , Intervenção Coronária Percutânea , Humanos , Prognóstico , Síndrome Coronariana Aguda/diagnóstico , Síndrome Coronariana Aguda/terapia , Intervenção Coronária Percutânea/efeitos adversos , Estudos de Coortes , Fatores de Risco , Albumina Sérica , Glucose
17.
Sex Transm Dis ; 50(4): 236-240, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36729091

RESUMO

BACKGROUND: Actively screening for Chlamydia trachomatis (CT) is important for young people because of a high prevalence of asymptomatic infection in this population. This study aimed to investigate knowledge on CT and preference to the screening services for CT among young students in China. METHODS: From June to July 2022, a web-based questionnaire survey was conducted to collect information on sociodemographic characteristics, sexual behaviors, knowledge of CT, previous testing for CT, and preference to platform of testing for CT among Chinese young students. An online home-based self-sampling test (HBSST) service was offered free of charge if the participant was willing to be tested for CT. Statistical analyses included descriptive analysis, χ 2 test, and multivariable logistic regression. RESULTS: Of 520 participants, 419 (80.6%) were aged between 16 and 24 years, 235 (45.2%) reported having sexual experience in the past, and 27 (5.2%) being tested before for CT. Slightly higher than 10% (57/520) of students were knowledgeable about CT. About one-third (36.9%) expressed their willingness to have a testing for CT but majority of them (63.1%) preferred to a free testing. Having sexual experience was significantly associated with the willingness to take the HBSST service (adjusted odds ratio, 2.96; 95% confidence interval, 1.92-4.58). A total of 139 (26.7%) participants requested the HBSST service online and 43.2% (60/139) returned the specimen for testing, in which 2 positives (3.3%) were found. CONCLUSIONS: The knowledge on CT and the previous uptake or current willingness to have a testing for CT was low among Chinese young students.


Assuntos
Infecções por Chlamydia , Chlamydia trachomatis , Humanos , Adolescente , Adulto Jovem , Adulto , Infecções por Chlamydia/diagnóstico , Infecções por Chlamydia/epidemiologia , Comportamento Sexual , Inquéritos e Questionários , Estudantes , China/epidemiologia , Programas de Rastreamento
18.
Theor Appl Genet ; 136(4): 77, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36952041

RESUMO

KEY MESSAGE: Seventy-three QTL related to grain color and tannin content were identified in Chinese sorghum accessions, and a new recessive allelic variant of TAN2 gene was discovered. Sorghum is mainly used for brewing distilled liquors in China. Since grain tannins play an important role in liquor brewing, accurately understanding the relationship between grain color and tannin content can provide basis for selection standards of tannin sorghum. We resequenced a panel of 242 Chinese sorghum accessions and performed population structure and genome-wide association study (GWAS) to identify quantitative trait locus (QTL) affecting pericarp color, testa pigment, and tannin content. Phylogenetic analysis, principal component analysis (PCA), and admixture model were used to infer population structure. Two distinct genetic sub-populations were identified according to their corresponding northern and southern geographic origin. To investigate the genetic basis of natural variation in sorghum grain color, GWAS with 2,760,264 SNPs was conducted in four environments using multiple models (Blink, FarmCPU, GLM, and MLM). Seventy-three QTL were identified to be associated for the color of exocarp, mesocarp, testa, and tannin content on all chromosomes except chromosome 5, of which 47 might be novel QTL. Some important QTL were found to colocalize with orthologous genes in the flavonoid biosynthetic pathway from other plants, including orthologous of Arabidopsis (Arabidopsis thaliana) TT2, TT7, TT12, TT16 and AT5G41220 (GST), as well as orthologous of rice (Oryza sativa) MYB61 and OsbHLH025. Our investigation of the variation in grain color and tannin content in Chinese sorghum germplasm may help guide future sorghum breeding for liquor brewing.


Assuntos
Estudo de Associação Genômica Ampla , Sorghum , Grão Comestível/genética , Filogenia , Melhoramento Vegetal , Sorghum/genética , Taninos/análise
19.
J Chem Phys ; 158(12): 124305, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-37003722

RESUMO

Quantum interference effects in conjugated molecules have been well-explored, with benzene frequently invoked as a pedagogical example. These interference effects have been understood through a quantum interference map in which the electronic transmission is separated into interfering and non-interfering terms, with a focus on the π-orbitals for conjugated molecules. Recently, saturated molecules have also been reported to exhibit destructive quantum interference effects; however, the very different σ-orbital character in these molecules means that it is not clear how orbital contributions manifest. Herein, we demonstrate that the quantum interference effects in conjugated molecules are quite different from those observed in saturated molecules, as demonstrated by the quantum interference map. While destructive interference at the Fermi energy in the π-system of benzene arises from interference terms between paired occupied and virtual orbitals, this is not the case at the Fermi energy in saturated systems. Instead, destructive interference is evident when contributions from a larger number of non-paired orbitals cancel, leading to more subtle and varied manifestations of destructive interference in saturated systems.

20.
Ren Fail ; 45(1): 2158869, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36637006

RESUMO

Purpose: Abdominal aortic calcification (AAC) assessed by using standard lateral lumbar radiographs can be graded, and composite summary scores (range, 0-24) have been shown to be highly predictive of subsequent cardiovascular morbidity and mortality in hemodialysis (HD) patients. However, few studies have sought to determine the optimal AAC score cutoff values for the prediction of mortality among HD patients.Methods: This retrospective cohort study included 408 hemodialysis patients. AAC severity was quantified by the AAC score, which was measured by lateral lumbar radiography with complete follow-up data from January 2015 to December 2021. We used receiver operating characteristic (ROC) analysis to find the cutoff AAC value for the prediction of mortality. The Kaplan-Meier method was used to analyze all-cause and cardiovascular mortality.Results: The cutoff calcification score for the prediction of mortality was 4.5 (sensitivity, 67.3%; specificity, 70.4%). The patients with AAC scores above 4.5 had significantly higher all-cause (log-rank p < 0.001) and cardiovascular (log-rank p < 0.001) mortality rates than those with AAC scores below 4.5. In the multivariate regression analyses, an AAC score above 4.5 was a significant factor associated with all-cause mortality (HR: 2.079, p = 0.002) and cardiovascular mortality (HR: 2.610, p < 0.001).Conclusions: AAC is a reliable aortic calcification marker. HD patients with an AAC score > 4.5 have significantly elevated all-cause and cardiovascular mortality compared with those with an AAC score ≤ 4.5. AAC was a better predictor than cardiac valve calcification for mortality in HD patients.


Assuntos
Doenças da Aorta , Calcificação Vascular , Humanos , Estudos Retrospectivos , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/etiologia , Fatores de Risco , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/complicações , Diálise Renal/efeitos adversos
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