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1.
Nature ; 595(7866): 245-249, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34234333

RESUMO

Single-phase high- and medium-entropy alloys with face-centred cubic (fcc) structure can exhibit high tensile ductility1,2 and excellent toughness2,3, but their room-temperature strengths are low1-3. Dislocation obstacles such as grain boundaries4, twin boundaries5, solute atoms6 and precipitates7-9 can increase strength. However, with few exceptions8-11, such obstacles tend to decrease ductility. Interestingly, precipitates can also hinder phase transformations12,13. Here, using a model, precipitate-strengthened, Fe-Ni-Al-Ti medium-entropy alloy, we demonstrate a strategy that combines these dual functions in a single alloy. The nanoprecipitates in our alloy, in addition to providing conventional strengthening of the matrix, also modulate its transformation from fcc-austenite to body-centred cubic (bcc) martensite, constraining it to remain as metastable fcc after quenching through the transformation temperature. During subsequent tensile testing, the matrix progressively transforms to bcc-martensite, enabling substantial increases in strength, work hardening and ductility. This use of nanoprecipitates exploits synergies between precipitation strengthening and transformation-induced plasticity, resulting in simultaneous enhancement of tensile strength and uniform elongation. Our findings demonstrate how synergistic deformation mechanisms can be deliberately activated, exactly when needed, by altering precipitate characteristics (such as size, spacing, and so on), along with the chemical driving force for phase transformation, to optimize strength and ductility.

2.
J Am Chem Soc ; 146(21): 14422-14426, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38709624

RESUMO

Here we report a concise and divergent synthesis of scabrolide A and havellockate, representative members of polycyclic marine natural product furano(nor)cembranoids. The synthesis features a highly efficient exo-exo-endo radical cascade. Through the generation of two rings, three C-C bonds, and three contiguous stereocenters in one step, this remarkable transformation not only assembles the bowl-shaped, common 6-5-5 fused ring system from simple building blocks but also precisely installs the functionalities at desired positions and sets the stage for further divergent preparation of both target molecules. Further studies reveal that the robust and unusual 6-endo radical addition in the cascade is likely facilitated by the rigidity of the substrate.

3.
Hepatology ; 77(6): 1998-2015, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36815382

RESUMO

BACKGROUND AND AIMS: Liver fibrosis results from the accumulation of myofibroblasts (MFs) derived from quiescent HSCs, and yes-associated protein (YAP) controls this state transition. Although fibrosis is also influenced by HSC death and senescence, whether YAP regulates these processes and whether this could be leveraged to treat liver fibrosis are unknown. APPROACH AND RESULTS: YAP activity was manipulated in MF-HSCs to determine how YAP impacts susceptibility to pro-apoptotic senolytic agents or ferroptosis. Effects of senescence on YAP activity and susceptibility to apoptosis versus ferroptosis were also examined. CCl 4 -treated mice were treated with a ferroptosis inducer or pro-apoptotic senolytic to determine the effects on liver fibrosis. YAP was conditionally disrupted in MFs to determine how YAP activity in MF-HSC affects liver fibrosis in mouse models. Silencing YAP in cultured MF-HSCs induced HSC senescence and vulnerability to senolytics, and promoted ferroptosis resistance. Conversely, inducing HSC senescence suppressed YAP activity, increased sensitivity to senolytics, and decreased sensitivity to ferroptosis. Single-cell analysis of HSCs from fibrotic livers revealed heterogeneous sensitivity to ferroptosis, apoptosis, and senescence. In mice with chronic liver injury, neither the ferroptosis inducer nor senolytic improved fibrosis. However, selectively depleting YAP in MF-HSCs induced senescence and decreased liver injury and fibrosis. CONCLUSION: YAP determines whether MF-HSCs remain activated or become senescent. By regulating this state transition, Yap controls both HSC fibrogenic activity and susceptibility to distinct mechanisms for cell death. MF-HSC-specific YAP depletion induces senescence and protects injured livers from fibrosis. Clarifying determinants of HSC YAP activity may facilitate the development of novel anti-fibrotic therapies.


Assuntos
Cirrose Hepática , Senoterapia , Camundongos , Animais , Cirrose Hepática/patologia , Fígado/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Morte Celular , Células Estreladas do Fígado/metabolismo
4.
Hepatology ; 78(4): 1209-1222, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37036206

RESUMO

BACKGROUND AND AIMS: Senescent hepatocytes accumulate in parallel with fibrosis progression during NASH. The mechanisms that enable progressive expansion of nonreplicating cell populations and the significance of that process in determining NASH outcomes are unclear. Senescing cells upregulate thrombomodulin-protease-activated receptor-1 (THBD-PAR1) signaling to remain viable. Vorapaxar blocks the activity of that pathway. We used vorapaxar to determine if and how THBD-PAR1 signaling promotes fibrosis progression in NASH. APPROACH AND RESULTS: We evaluated the THBD-PAR1 pathway in liver biopsies from patients with NAFLD. Chow-fed mice were treated with viral vectors to overexpress p16 in hepatocytes and induce replicative senescence. Effects on the THBD-PAR1 axis and regenerative capacity were assessed; the transcriptome of p16-overexpressing hepatocytes was characterized, and we examined how conditioned medium from senescent but viable (dubbed "undead") hepatocytes reprograms HSCs. Mouse models of NASH caused by genetic obesity or Western diet/CCl 4 were treated with vorapaxar to determine effects on hepatocyte senescence and liver damage. Inducing senescence upregulates the THBD-PAR1 signaling axis in hepatocytes and induces their expression of fibrogenic factors, including hedgehog ligands. Hepatocyte THBD-PAR1 signaling increases in NAFLD and supports sustained hepatocyte senescence that limits effective liver regeneration and promotes maladaptive repair. Inhibiting PAR1 signaling with vorapaxar interrupts this process, reduces the burden of 'undead' senescent cells, and safely improves NASH and fibrosis despite ongoing lipotoxic stress. CONCLUSION: The THBD-PAR1 signaling axis is a novel therapeutic target for NASH because blocking this pathway prevents accumulation of senescing but viable hepatocytes that generate factors that promote maladaptive liver repair.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptor PAR-1/metabolismo , Trombomodulina/metabolismo , Hepatócitos/metabolismo , Fígado/patologia , Fibrose , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
5.
Int Wound J ; 21(4): e14605, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38149500

RESUMO

The objective of this study was to investigate the risk factors associated with surgical site infection (SSI) after percutaneous endoscopic lumbar discectomy (PELD) in patients with lumbar disc herniation (LDH). A retrospective analysis was performed on a cohort of 335 patients who underwent PELD between January 2016 and January 2023. Data were derived from the Hospital Information System (HIS), and a comprehensive statistical assessment was performed using IBM SPSS Statistics version 25.0. Both univariate and multivariate logistic regression analyses assessed a range of risk determinants, such as age, body mass index (BMI), comorbidities, laboratory test parameters and surgery-related variables. The incidence of SSI after PELD was 2.7% (9/335). Univariate analysis highlighted BMI, diabetes mellitus, long-term corticosteroid consumption, surgical time and cerebrospinal fluid leakage as significant predictors of SSI. Multivariate logistic regression identified BMI, diabetes mellitus, long-term corticosteroid consumption, surgical time and cerebrospinal fluid leakage as significant risk factors for SSI after PELD. High BMI, diabetes mellitus, long-term corticosteroid consumption, long surgical time and postoperative cerebrospinal fluid leakage are predisposing factors for SSI in patients undergoing PELD. Precise interventions focused on such risk components, including careful preoperative assessment and strategic postoperative care, are essential to reduce the incidence of SSI and improve surgical efficacy.


Assuntos
Diabetes Mellitus , Discotomia Percutânea , Deslocamento do Disco Intervertebral , Humanos , Estudos Retrospectivos , Deslocamento do Disco Intervertebral/epidemiologia , Deslocamento do Disco Intervertebral/etiologia , Deslocamento do Disco Intervertebral/cirurgia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgia , Discotomia Percutânea/efeitos adversos , Vértebras Lombares/cirurgia , Fatores de Risco , Corticosteroides , Vazamento de Líquido Cefalorraquidiano/etiologia , Vazamento de Líquido Cefalorraquidiano/cirurgia , Resultado do Tratamento
6.
J Environ Sci (China) ; 142: 21-32, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38527886

RESUMO

In the context of carbon capture, utilization, and storage, the high-value utilization of carbon storage presents a significant challenge. To address this challenge, this study employed the bipolar membrane electrodialysis integrated with carbon utilization technology to prepare Na2CO3 products using simulated seawater concentrate, achieving simultaneous saline wastewater utilization, carbon storage and high-value production of Na2CO3. The effects of various factors, including concentration of simulated seawater concentrate, current density, CO2 aeration rate, and circulating flow rate of alkali chamber, on the quality of Na2CO3 product, carbon sequestration rate, and energy consumption were investigated. Under the optimal condition, the CO32- concentration in the alkaline chamber reached a maximum of 0.817 mol/L with 98 mol% purity. The resulting carbon fixation rate was 70.50%, with energy consumption for carbon sequestration and product production of 5.7 kWhr/m3 CO2 and 1237.8 kWhr/ton Na2CO3, respectively. This coupling design provides a triple-win outcome promoting waste reduction and efficient utilization of resources.


Assuntos
Dióxido de Carbono , Carbono , Carbonatos , Água do Mar , Sódio
7.
BMC Med ; 21(1): 227, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37365601

RESUMO

BACKGROUND: Pneumonia is a common disease worldwide in preschool children. Despite its large population size, China has had no comprehensive study of the national prevalence, risk factors, and management of pneumonia among preschool children. We therefore investigated the prevalence of pneumonia among preschool children in Chinese seven representative cities, and explore the possible risk factors of pneumonia on children, with a view to calling the world's attention to childhood pneumonia to reduce the prevalence of childhood pneumonia. METHODS: Two group samples of 63,663 and 52,812 preschool children were recruited from 2011 and 2019 surveys, respectively. Which were derived from the cross-sectional China, Children, Homes, Health (CCHH) study using a multi-stage stratified sampling method. This survey was conducted in kindergartens in seven representative cities. Exclusion criteria were younger than 2 years old or older than 8 years old, non-permanent population, basic information such as gender, date of birth and breast feeding is incomplete. Pneumonia was determined on the basis of parents reported history of clearly diagnosed by the physician. All participants were assessed with a standard questionnaire. Risk factors for pneumonia, and association between pneumonia and other respiratory diseases were examined by multivariable-adjusted analyses done in all participants for whom data on the variables of interest were available. Disease management was evaluated by the parents' reported history of physician diagnosis, longitudinal comparison of risk factors in 2011 and 2019. RESULTS: In 2011 and 2019, 31,277 (16,152 boys and 15,125 girls) and 32,016 (16,621 boys and 15,395 girls) preschool children aged at 2-8 of permanent population completed the questionnaire, respectively, and were thus included in the final analysis. The findings showed that the age-adjusted prevalence of pneumonia in children was 32.7% in 2011 and 26.4% in 2019. In 2011, girls (odds ratio [OR] 0.91, 95%CI [confidence interval]0.87-0.96; p = 0.0002), rural (0.85, 0.73-0.99; p = 0.0387), duration of breastfeeding ≥ 6 months(0.83, 0.79-0.88; p < 0.0001), birth weight (g) ≥ 4000 (0.88, 0.80-0.97; p = 0.0125), frequency of putting bedding to sunshine (Often) (0.82, 0.71-0.94; p = 0.0049), cooking fuel type (electricity) (0.87, 0.80-0.94; p = 0.0005), indoor use air-conditioning (0.85, 0.80-0.90; p < 0.0001) were associated with a reduced risk of childhood pneumonia. Age (4-6) (1.11, 1.03-1.20; p = 0.0052), parental smoking (one) (1.12, 1.07-1.18; p < 0.0001), used antibiotics (2.71, 2.52-2.90; p < 0.0001), history of parental allergy (one and two) (1.21, 1.12-1.32; p < 0.0001 and 1.33, 1.04-1.69; p = 0.0203), indoor dampness (1.24, 1.15-1.33; p < 0.0001), home interior decoration (1.11, 1.04-1.19; p = 0.0013), Wall painting materials (Paint) (1.16, 1.04-1.29; p = 0.0084), flooring materials (Laminate / Composite wood) (1.08, 1.02-1.16; p = 0.0126), indoor heating mode(Central heating)(1.18, 1.07-1.30, p = 0.0090), asthma (2.38, 2.17-2.61; p < 0.0001), allergic rhinitis (1.36, 1.25-1.47; p < 0.0001), wheezing (1.64, 1.55-1.74; p < 0.0001) were associated with an elevated risk of childhood pneumonia; pneumonia was associated with an elevated risk of childhood asthma (2.53, 2.31-2.78; p < 0.0001), allergic rhinitis (1.41, 1.29-1.53; p < 0.0001) and wheezing (1.64, 1.55-1.74; p < 0.0001). In 2019, girls (0.92, 0.87-0.97; p = 0.0019), duration of breastfeeding ≥ 6 months (0.92, 0.87-0.97; p = 0.0031), used antibiotics (0.22, 0.21-0.24; p < 0.0001), cooking fuel type (Other) (0.40, 0.23-0.63; p = 0.0003), indoor use air-conditioning (0.89, 0.83-0.95; p = 0.0009) were associated with a reduced risk of childhood pneumonia. Urbanisation (Suburb) (1.10, 1.02-1.18; p = 0.0093), premature birth (1.29, 1.08-1.55; p = 0.0051), birth weight (g) < 2500 (1.17, 1.02-1.35; p = 0.0284), parental smoking (1.30, 1.23-1.38; p < 0.0001), history of parental asthma (One) (1.23, 1.03-1.46; p = 0.0202), history of parental allergy (one and two) (1.20, 1.13-1.27; p < 0.0001 and 1.22, 1.08-1.37; p = 0.0014), cooking fuel type (Coal) (1.58, 1.02-2.52; p = 0.0356), indoor dampness (1.16, 1.08-1.24; p < 0.0001), asthma (1.88, 1.64-2.15; p < 0.0001), allergic rhinitis (1.57, 1.45-1.69; p < 0.0001), wheezing (2.43, 2.20-2.68; p < 0.0001) were associated with an elevated risk of childhood pneumonia; pneumonia was associated with an elevated risk of childhood asthma (1.96, 1.72-2.25; p < 0.0001), allergic rhinitis (1.60, 1.48-1.73; p < 0.0001) and wheezing (2.49, 2.25-2.75; p < 0.0001). CONCLUSIONS: Pneumonia is prevalent among preschool children in China, and it affects other childhood respiratory diseases. Although the prevalence of pneumonia in Chinese children shows a decreasing trend in 2019 compared to 2011, a well-established management system is still needed to further reduce the prevalence of pneumonia and reduce the burden of disease in children.


Assuntos
Asma , Pneumonia , Rinite Alérgica , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Asma/epidemiologia , Peso ao Nascer , China/epidemiologia , Cidades , Estudos Transversais , População do Leste Asiático , Análise de Séries Temporais Interrompida , Pneumonia/epidemiologia , Prevalência , Sons Respiratórios/etiologia , Rinite Alérgica/complicações , Fatores de Risco , Inquéritos e Questionários
8.
Allergy ; 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37458141

RESUMO

BACKGROUND: The urban ambient air quality has been largely improved in the past decade. It is unknown whether childhood asthma prevalence is still increasing in ever top-ranking city of Shanghai, whether the improved air quality is beneficial for children's asthma and what time window of exposure plays critical roles. METHODS: Using a repeat cross-sectional design, we analyzed the association between early life exposure to particles and wheezing/asthma in each individual and combined surveys in 2011 and 2019, respectively, in 11,825 preschool children in Shanghai. RESULTS: A significantly lower prevalence of doctor-diagnosed asthma (DDA) (6.6% vs. 10.5%, p < 0.001) and wheezing (10.5% vs. 23.2%, p < 0.001) was observed in 2019 compared to 2011. Exposure to fine particulate matter (PM2.5 ), coarse particles (PM2.5-10 ) and inhalable particles (PM10 ) was decreased in 2019 by 6.3%, 35.4%, and 44.7% in uterus and 24.3%, 20.2%, and 31.8% in infancy, respectively. Multilevel log-binomial regression analysis showed exposure in infancy had independent association with wheezing/DDA adjusting for exposure in uterus. For each interquartile range (IQR) increase of infancy PM2.5 , PM2.5-10 and PM10 exposure, the odds ratios were 1.39 (95% confidence interval (CI): 1.24-1.56), 1.51 (95% CI:1.15-1.98) and 1.53 (95% CI:1.27-1.85) for DDA, respectively. The distributed lag non-linear model showed the sensitive exposure window (SEW) was 5.5-11 months after birth. Stratified analysis showed the SEWs were at or shortly after weaning, but only in those with <6 months of exclusive breastfeeding. CONCLUSIONS: Improved ambient PM benefits in decreasing childhood asthma prevalence. We firstly reported the finding of SEW to PM at or closely after weaning on childhood asthma.

9.
Pestic Biochem Physiol ; 194: 105526, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532338

RESUMO

Methidathion is a highly effective organophosphorus pesticide and is extensively utilized for the control of insects in agricultural production. However, there is little information on the adverse effects and underlying mechanisms of methidathion on aquatic organisms. In this work, embryonic zebrafish were exposed to methidathion at concentrations of 4, 10, and 25 mg/L for 96 h, and morphological changes and activities of antioxidant indicators alterations were detected. In addition, the locomotor behavioral abilities of zebrafish exposed to methidathion were also measured. To further explore the mechanism of the toxic effects of methidathion, gene expression levels associated with cardiac development, cell apoptosis, and the immune system were tested through qPCR assays. The findings revealed that methidathion exposure could induce a decrease in survival rate, hatchability, length of body, and increase in abnormality of zebrafish, as well as cardiac developmental toxicity. The LC50 value of methidathion in zebrafish embryos was determined to be about 30.72 mg/L at 96 hpf. Additionally, methidathion exposure triggered oxidative stress in zebrafish by increasing SOD activity, ROS, and MDA content. Acridine orange (AO) staining indicated that methidathion exposure led to apoptosis, which was mainly distributed in the pericardial region. Furthermore, significant impairments of locomotor activity in zebrafish larvae were induced by methidathion exposure. Lastly, the expression of pro-inflammatory factors including IFN-γ, IL-6, IL-8, CXCL-clc, TLR4, and MYD88 significantly up-regulated in exposed zebrafish. Taken together, the results in this work illustrated that methidathion caused developmental toxicity, cardiotoxicity, and immunotoxicity in embryogenetic zebrafish.


Assuntos
Praguicidas , Poluentes Químicos da Água , Animais , Peixe-Zebra , Cardiotoxicidade/metabolismo , Compostos Organofosforados/metabolismo , Praguicidas/farmacologia , Estresse Oxidativo , Embrião não Mamífero , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
10.
Int J Mol Sci ; 24(4)2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36834564

RESUMO

Papillary Thyroid Carcinoma (PTC) is characterized by unique tumor morphology, treatment response, and patient outcomes according to subtype and gender. While previous studies have implicated the intratumor bacterial microbiome in the incidence and progression of PTC, few studies have investigated the potential role of fungal and archaeal species in oncogenesis. In this study, we aimed to characterize the intratumor mycobiome and archaeometry in PTC with respect to its three primary subtypes: Classical (CPTC), Follicular Variant (FVPTC), and Tall Cell (TCPTC), and also with respect to gender. RNA-sequencing data were downloaded from The Cancer Genome Atlas (TCGA), including 453 primary tumor tissue samples and 54 adjacent solid tissue normal samples. The PathoScope 2.0 framework was used to extract fungal and archaeal microbial read counts from raw RNA-sequencing data. Overall, we found that the intratumor mycobiome and archaeometry share significant similarities in CPTC, FVPTC, and TCPTC, although most dysregulated species in CPTC are underabundant compared to normal. Furthermore, differences between the mycobiome and archaeometry were more significant between males and females, with a disproportionate number of fungal species overabundant in female tumor samples. Additionally, the expression of oncogenic PTC pathways was distinct across CPTC, FVPTC, and TCPTC, indicating that these microbes may uniquely contribute to PTC pathogenesis in each subtype. Furthermore, differences in the expression of these pathways were observed between males and females. Finally, we found a specific panel of fungi to be dysregulated in BRAF V600E-positive tumors. This study demonstrates the potential importance of microbial species to PTC incidence and oncogenesis.


Assuntos
Carcinoma Papilar , Micobioma , Neoplasias da Glândula Tireoide , Masculino , Humanos , Feminino , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/patologia , Carcinoma Papilar/patologia , Transcriptoma , RNA , Carcinogênese , Proteínas Proto-Oncogênicas B-raf/genética
11.
Int J Mol Sci ; 24(7)2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37047745

RESUMO

P2ry12 is a microglial marker gene. Recently, increasing evidence has demonstrated that its expression levels can vary in response to different CNS disorders and can affect microglial functions, such as polarization, plasticity, and migration. However, the expression and function of P2ry12 in microglia during ischemia-reperfusion injury (IRI) remain unclear. Here, we developed a computational method to obtain microglia-specific P2ry12 genes (MSPGs) using sequencing data associated with IRI. We evaluated the change in comprehensive expression levels of MSPGs during IRI and compared it to the expression of P2ry12 to determine similarity. Subsequently, the MSPGs were used to explore the P2ry12 functions in microglia through bioinformatics. Moreover, several animal experiments were also conducted to confirm the reliability of the results. The expression of P2ry12 was observed to decrease gradually within 24 h post injury. In response, microglia with reduced P2ry12 expression showed an increase in the expression of one receptor-encoding gene (Flt1) and three ligand-encoding genes (Nampt, Igf1, and Cxcl2). Furthermore, double-labeling immunofluorescence staining revealed that inhibition of P2ry12 blocked microglial migration towards vessels during IRI. Overall, we employ a combined computational and experimental approach to successfully explore P2ry12 expression and function in microglia during IRI.


Assuntos
Microglia , Traumatismo por Reperfusão , Animais , Microglia/metabolismo , Reprodutibilidade dos Testes , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo
12.
Appl Environ Microbiol ; 88(7): e0221521, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35311507

RESUMO

Rhodotorula mucilaginosa shows adaption to a broad range of Pb2+ stress. In this study, three key pathways, i.e., glycolysis (EMP), the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OXPHOS), were investigated under 0-2,500 mg · L-1 Pb stress, primarily based on biochemical analysis and RNA sequencing. R. mucilaginosa cells showed similar metabolic response to low/medium (500/1000 mg · L-1) Pb2+ stress. High (2,500 mg · L-1) Pb2+ stress exerted severe cytotoxicity to R. mucilaginosa. The downregulation of HK under low-medium Pb2+ suggested a correlation with the low hexokinase enzymatic activity in vivo. However, IDH3, regulating a key step of circulation in TCA, was upregulated to promote ATP feedstock for downstream OXPHOS. Then, through activation of complex I & IV in the electron transport chain (ETC) and ATP synthase, ATP production was finally enhanced. This mechanism enabled fungal cells to compensate for ATP consumption under low-medium Pb2+ toxicity. Hence, R. mucilaginosa tolerance to such a broad range of Pb2+ concentrations can be attributed to energy adaption. In contrast, high Pb2+ stress caused ATP deficiency. Then, the subsequent degradation of intracellular defense systems further intensified Pb toxicity. This study correlated responses of EMP, TCA, and OXPHOS pathways in R. mucilaginosa under Pb stress, hence providing new insights into the fungal resistance to heavy metal stress. IMPORTANCE Glycolysis (EMP), the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation (OXPHOS) are critical metabolism pathways for microorganisms to obtain energy during the resistance to heavy metal (HM) stress. However, these pathways at the genetic level have not been elucidated to evaluate their cytoprotective functions for Rhodotorula mucilaginosa under Pb stress. In this study, we investigated these three pathways based on biochemical analysis and RNA sequencing. Under low-medium (500-1,000 mg · L-1) Pb2+ stress, ATP production was stimulated mainly due to the upregulation of genes associated with the TCA cycle and the electron transport chain (ETC). Such an energy compensatory mechanism could allow R. mucilaginosa acclimation to a broad range of Pb2+ concentrations (up to 1000 mg · L-1). In contrast, high (2500 mg · L-1) Pb2+ stress exerted its excessive toxicity by provoking ATP deficiency and damage to intracellular resistance systems. This study provided new insights into R. mucilaginosa resistance to HM stress from the perspective of metabolism.


Assuntos
Chumbo , Metais Pesados , Trifosfato de Adenosina , Ciclo do Ácido Cítrico , Perfilação da Expressão Gênica , Chumbo/toxicidade , Rhodotorula , Ácidos Tricarboxílicos
13.
Eur J Nutr ; 61(8): 4077-4089, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35809101

RESUMO

PURPOSE: Chronic low-grade systemic inflammation affects muscle protein metabolism. The dietary inflammatory index (DII®) is a tool designed to assess the inflammatory potential of the diet. The available data on the association between DII and sarcopenia are limited. We aimed to investigate the association of the DII with components of sarcopenia in individuals over 50 years of age. METHODS: This cross-sectional study used the National Health and Nutrition Examination Survey (NHANES) 1999-2002 dataset. Body composition was measured, and isokinetic strength of the knee extensors (peak force) was evaluated. Low muscle mass and strength were defined using sex-specific thresholds. Energy-adjusted DII (E-DII™) scores were calculated using 24-h dietary recall data. Regression models were fit to evaluate the association between E-DII scores and low muscle mass and low muscle strength, alone and combined. RESULTS: Mean age of study participants was 62.1 ± 9.5 years, and 138 participants (7.4%) belonged to the combination group of low muscle mass and low muscle strength. In multivariable-adjusted regression models, higher E-DII score was associated with lower appendicular skeletal muscle index (ASMI) (ß = - 0.03, P  < 0.001, P trend <0.001), and lower peak force (ß = -2.15, P  = 0.04, P trend = 0.01) and higher likelihood for these components combined (OR = 1.12, 95% CI 1.01-1.25, P = 0.03). CONCLUSION: Higher E-DII score is associated with lower muscle mass and muscle strength, and increased likelihood for the combination of low muscle mass and low muscle strength in older adults. This has important implications for healthy aging.


Assuntos
Sarcopenia , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Inquéritos Nutricionais , Estudos Transversais , Sarcopenia/epidemiologia , Dieta , Inflamação/metabolismo , Músculos/metabolismo , Proteínas Musculares
14.
J Appl Toxicol ; 42(6): 1067-1077, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34967033

RESUMO

Anisodamine is one of the major components of the tropine alkaloid family and is widely used in the treatment of pain, motion sickness, pupil dilatation, and detoxification of organophosphorus poisoning. As a muscarinic receptor antagonist, the low toxicity and moderate drug effect of anisodamine often result in high doses for clinical use, making it important to fully investigate its toxicity. In this study, zebrafish embryos were exposed to 1.3-, 2.6-, and 5.2-mM anisodamine for 7 days to study the toxic effects of drug exposure on pigmentation, mineral density, craniofacial area, and eye development. The results showed that exposure to anisodamine at 1.3 mM resulted in cranial malformations and abnormal pigmentation in zebrafish embryos; 2.6- and 5.2-mM anisodamine resulted in significant eye development defects and reduced bone density in zebrafish embryos. The associated toxicities were correlated with functional development of neural crest cells through gene expression (col1a2, ddb1, dicer1, mab21l1, mab21l2, sox10, tyrp1b, and mitfa) in the dose of 5.2-mM exposed group. In conclusion, this study provides new evidence of the developmental toxicity of high doses of anisodamine in aqueous solutions to organisms and provides a warning for the safe use of this drug.


Assuntos
Alcaloides de Solanáceas , Peixe-Zebra , Animais , Embrião não Mamífero , Minerais/metabolismo , Minerais/farmacologia , Pigmentação , Alcaloides de Solanáceas/metabolismo , Alcaloides de Solanáceas/farmacologia , Alcaloides de Solanáceas/uso terapêutico , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
15.
Chemistry ; 27(47): 12041-12046, 2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34159657

RESUMO

It has only recently been established that doping light elements (lithium, boron, and carbon) into supported transition metals can fill interstitial sites, which can be observed by the expanded unit cell. As an example, interstitial lithium (int Li) can block H filling octahedral interstices of palladium metal lattice, which improves partial hydrogenation of alkynes to alkenes under hydrogen. In contrast, herein, we report int Li is not found in the case of Pt/C. Instead, we observe for the first time a direct 'substitution' of Pt with substitutional lithium (sub Li) in alternating atomic columns using scanning transmission electron microscopy-annular dark field (STEM-ADF). This ordered substitutional doping results in a contraction of the unit cell as shown by high-quality synchrotron X-ray diffraction (SXRD). The electron donation of d-band of Pt without higher orbital hybridizations by sub Li offers an alternative way for ultra-selectivity in catalytic hydrogenation of carbonyl compounds by suppressing the facile CO bond breakage that would form alcohols.

16.
Cell Biol Int ; 45(5): 976-988, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33377585

RESUMO

Articular cartilage damage and chondrocyte apoptosis are common features of rheumatoid arthritis and osteoarthritis. Recently, curcumin has been reported to exhibit protective effects on degeneration in articular cartilage diseases. However, the effects and mechanisms of curcumin on articular chondrocyte injury remain to be elucidated. The aim of the present study is to investigate the chondroprotective mechanisms of curcumin on interleukin-1ß (IL-1ß)-induced chondrocyte apoptosis in vitro. The results revealed that IL-1ß decreased cell viability and induced apoptosis in primary articular chondrocytes. Curcumin pretreatment reduced IL-1ß-induced articular chondrocyte apoptosis. In addition, treatment with curcumin increased autophagy in articular chondrocytes and protected against IL-1ß-induced apoptosis. The curcumin-mediated protection against IL-1ß induced apoptosis was abolished when cells were treated with the autophagy inhibitor 3-methyladenine or transfected with Beclin-1 small interfering RNA. Furthermore, IL-1ß stimulation significantly increased the phosphorylation levels of nuclear factor (NF)-κB p65 and glycogen synthase kinase-3ß, and decreased the phosphorylation levels of ß-catenin in articular chondrocytes, and these alterations to the phosphorylation levels were partly reversed by treatment with curcumin. Dual-luciferase and electrophoretic mobility shift assays demonstrated that IL-1ß increased NF-κB p65 promoter activity in chondrocytes, and this was also reversed by curcumin. Pretreatment with the NF-κB inhibitor pyrrolidine dithiocarbamate enhanced the protective effects of curcumin on chondrocyte apoptosis, but Wnt/ß-catenin inhibitor, XAV-939, did not exhibit this effect. Molecular docking and dynamic simulation studies results showed that curcumin could bound to RelA (p65) protein. These results indicate that curcumin may suppress IL-1ß-induced chondrocyte apoptosis through activating autophagy and restraining NF-κB signaling pathway.


Assuntos
Autofagia/efeitos dos fármacos , Condrócitos/metabolismo , Curcumina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Autofagia/fisiologia , Cartilagem Articular/efeitos dos fármacos , Cartilagem Articular/metabolismo , Células Cultivadas , Condrócitos/efeitos dos fármacos , Curcumina/metabolismo , Interleucina-1beta/efeitos dos fármacos , Interleucina-1beta/metabolismo , Masculino , Simulação de Acoplamento Molecular , NF-kappa B/efeitos dos fármacos , NF-kappa B/metabolismo , Osteoartrite/metabolismo , Fosforilação/efeitos dos fármacos , Cultura Primária de Células , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos
17.
Angew Chem Int Ed Engl ; 60(39): 21449-21456, 2021 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-34314545

RESUMO

We successfully synthesized {BiW8 }, a 10-nuclear heteroatom cluster modified {BiW8 O30 }. At 24 h post-incubation, the IC50 values of {BiW8 } against HUVEC, MG63, RD, Hep3B, HepG2, and MCF7 cells were 895.8, 127.3, 344.3, 455.0, 781.3, and 206.3 µM, respectively. The IC50 value of {BiW8 } on the MG63 cells was more than 2-fold lower than that of the other raw materials. Through morphological and functional features, we demonstrated pyroptosis as a newly identified mechanism of cell death induced by {BiW8 }. {BiW8 } increased 2-fold reactive oxygen species (ROS) levels in MG63 cells at 24 h post-incubation. Compared with 0 h, the glutathione (GSH) content decreased by 59, 65, 75, 94, and 97 % at 6, 12, 24, 36 and 48 h post-incubation, respectively. Furthermore, multiple antitumor mechanisms of {BiW8 } were identified via transcriptome analysis and chemical simulation, including activation of pyroptosis, suppression of GSH generation, depletion of GSH, and inhibition of DNA repair.


Assuntos
Antineoplásicos/farmacologia , Piroptose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Compostos de Tungstênio/farmacologia , Regulação para Cima/efeitos dos fármacos , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Compostos de Tungstênio/química
18.
Biochem Biophys Res Commun ; 523(2): 315-321, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-31864712

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disease for which specific biomarkers and pathological mechanisms have yet to be identified. Methylphenidate (MPH) is commonly used to treat ADHD, but its therapeutic mechanisms and its impact on brain metabolites remain unclear. Metabolomics can help to discover biomarkers and identify pathophysiological mechanisms. We adopted an untargeted metabolomics approach based on gas chromatography-mass spectrometry to investigate the potential biomarkers and pathogenesis of ADHD. Ten Wistar-Kyoto (WKY) rats were chosen as healthy controls (vehicle, i.g.). Twenty young spontaneously hypertensive rats (SHR) were randomly allocated to the SHR group (vehicle, i.g.) and MPH group (2 mg/kg/day, i.g.). We identified 103 metabolites from the prefrontal cortex (PFC). Orthogonal partial least square-discriminate analysis showed the differential expression of these metabolites between the groups. Multivariate and univariate statistical analyses isolated 12 metabolites that differed significantly between the WKY and SHR groups: 3-hydroxymethylglutaric acid, 3-phosphoglyceric acid, adenosine monophosphate, cholesterol, lanosterol, and o-phosphoethanolamine; 3-hydroxymethylglutaric acid and cholesterol were reversed with MPH treatment. Pathway and enrichment analyses revealed that the altered metabolites belonged to the cholesterol metabolism pathways. ELISA and western blotting showed that the activity of 3-hydroxy-3-methyl-glutaryl-CoA reductase and the expression of sterol regulatory element-binding protein-2 and ATP-binding cassette transporter A1 were reduced in the PFC of the SHR; the latter two proteins were upregulated by MPH. In conclusion, metabolomics analysis identified potential biomarkers that influence cholesterol metabolism and may be implicated in the development of ADHD-like behavior. MPH can regulate cholesterol metabolism in the PFC of ADHD models. This study uncovered potential biomarkers and pathways involved in ADHD, providing new insight into its pathogenesis.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Colesterol/metabolismo , Córtex Pré-Frontal/metabolismo , Animais , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Biomarcadores/metabolismo , Estimulantes do Sistema Nervoso Central/uso terapêutico , Modelos Animais de Doenças , Masculino , Redes e Vias Metabólicas , Metabolômica , Metilfenidato/uso terapêutico , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
19.
Aust N Z J Psychiatry ; 54(5): 519-527, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31958975

RESUMO

OBJECTIVE: Previous studies showed alterations of brain function in the ventromedial prefrontal cortex of schizophrenia patients. Also, neurochemical changes, especially GABA level alteration, have been found in the medial prefrontal cortex of schizophrenia patients. However, the relationship between GABA level in the ventromedial prefrontal cortex and brain functional activity in schizophrenia patients remains unexplored. METHODS: In total, 23 drug-naïve, first-episode psychosis patients and 26 matched healthy controls completed the study. The single voxel proton magnetic resonance spectroscopy data were acquired in ventromedial prefrontal cortex region, which was used as the seed region for resting-state functional connectivity analysis. The proton magnetic resonance spectroscopy data were processed to quantify the concentrations of GABA+, glutamine and glutamate, and N-acetylaspartate in ventromedial prefrontal cortex. Spearman correlation analysis was used to examine the relationship between metabolite concentration, functional connectivity and clinical variables. Pearson correlation analysis was used to examine the relationship between GABA+ concentration and functional connectivity value. RESULTS: In first-episode psychosis patients, GABA+ level in ventromedial prefrontal cortex was higher and was positively correlated with ventromedial prefrontal cortex-left middle orbital frontal cortex functional connectivity. N-acetylaspartate level was positively correlated with positive symptoms, and the functional connectivity between ventromedial prefrontal cortex and left precuneus was negatively associated with negative symptoms of first-episode psychosis patients. CONCLUSION: Our results indicated that ventromedial prefrontal cortex functional connectivity changes were positively correlated with higher local GABA+ level in first-episode psychosis patients. The altered neurochemical concentration and functional connectivity provide insights into the pathology of schizophrenia.


Assuntos
Córtex Pré-Frontal , Transtornos Psicóticos , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Espectroscopia de Prótons por Ressonância Magnética , Transtornos Psicóticos/diagnóstico por imagem
20.
Angew Chem Int Ed Engl ; 59(37): 16039-16046, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32458500

RESUMO

There is increasing interest in capturing H2 generated from renewables with CO2 to produce methanol. However, renewable hydrogen production is expensive and in limited quantity compared to CO2 . Excess CO2 and limited H2 in the feedstock gas is not favorable for CO2 hydrogenation to methanol, causing low activity and poor methanol selectivity. Now, a class of Rh-In catalysts with optimal adsorption properties to the intermediates of methanol production is presented. The Rh-In catalyst can effectively catalyze methanol synthesis but inhibit the reverse water-gas shift reaction under H2 -deficient gas flow and shows the best competitive methanol productivity under industrially applicable conditions in comparison with reported values. This work demonstrates a strong potential of Rh-In bimetallic composition, from which a convenient methanol synthesis based on flexible feedstock compositions (such as H2 /CO2 from biomass derivatives) with lower energy cost can be established.

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