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1.
Circulation ; 149(9): 684-706, 2024 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-37994595

RESUMO

BACKGROUND: The majority of people with diabetes are susceptible to cardiac dysfunction and heart failure, and conventional drug therapy cannot correct diabetic cardiomyopathy progression. Herein, we assessed the potential role and therapeutic value of USP28 (ubiquitin-specific protease 28) on the metabolic vulnerability of diabetic cardiomyopathy. METHODS: The type 2 diabetes mouse model was established using db/db leptin receptor-deficient mice and high-fat diet/streptozotocin-induced mice. Cardiac-specific knockout of USP28 in the db/db background mice was generated by crossbreeding db/m and Myh6-Cre+/USP28fl/fl mice. Recombinant adeno-associated virus serotype 9 carrying USP28 under cardiac troponin T promoter was injected into db/db mice. High glucose plus palmitic acid-incubated neonatal rat ventricular myocytes and human induced pluripotent stem cell-derived cardiomyocytes were used to imitate diabetic cardiomyopathy in vitro. The molecular mechanism was explored through RNA sequencing, immunoprecipitation and mass spectrometry analysis, protein pull-down, chromatin immunoprecipitation sequencing, and chromatin immunoprecipitation assay. RESULTS: Microarray profiling of the UPS (ubiquitin-proteasome system) on the basis of db/db mouse hearts and diabetic patients' hearts demonstrated that the diabetic ventricle presented a significant reduction in USP28 expression. Diabetic Myh6-Cre+/USP28fl/fl mice exhibited more severe progressive cardiac dysfunction, lipid accumulation, and mitochondrial disarrangement, compared with their controls. On the other hand, USP28 overexpression improved systolic and diastolic dysfunction and ameliorated cardiac hypertrophy and fibrosis in the diabetic heart. Adeno-associated virus serotype 9-USP28 diabetic mice also exhibited less lipid storage, reduced reactive oxygen species formation, and mitochondrial impairment in heart tissues than adeno-associated virus serotype 9-null diabetic mice. As a result, USP28 overexpression attenuated cardiac remodeling and dysfunction, lipid accumulation, and mitochondrial impairment in high-fat diet/streptozotocin-induced type 2 diabetes mice. These results were also confirmed in neonatal rat ventricular myocytes and human induced pluripotent stem cell-derived cardiomyocytes. RNA sequencing, immunoprecipitation and mass spectrometry analysis, chromatin immunoprecipitation assays, chromatin immunoprecipitation sequencing, and protein pull-down assay mechanistically revealed that USP28 directly interacted with PPARα (peroxisome proliferator-activated receptor α), deubiquitinating and stabilizing PPARα (Lys152) to promote Mfn2 (mitofusin 2) transcription, thereby impeding mitochondrial morphofunctional defects. However, such cardioprotective benefits of USP28 were largely abrogated in db/db mice with PPARα deletion and conditional loss-of-function of Mfn2. CONCLUSIONS: Our findings provide a USP28-modulated mitochondria homeostasis mechanism that involves the PPARα-Mfn2 axis in diabetic hearts, suggesting that USP28 activation or adeno-associated virus therapy targeting USP28 represents a potential therapeutic strategy for diabetic cardiomyopathy.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Cardiomiopatias Diabéticas , Células-Tronco Pluripotentes Induzidas , Ubiquitina Tiolesterase , Animais , Humanos , Camundongos , Ratos , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Cardiomiopatias Diabéticas/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Lipídeos , Camundongos Knockout , Miócitos Cardíacos/metabolismo , PPAR alfa/metabolismo , Estreptozocina/metabolismo , Estreptozocina/uso terapêutico , Ubiquitina Tiolesterase/análise , Ubiquitina Tiolesterase/metabolismo
2.
FASEB J ; 38(13): e23785, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38949120

RESUMO

Cancer metastasis is the leading cause of death for those afflicted with cancer. In cancer metastasis, the cancer cells break off from the primary tumor, penetrate nearby blood vessels, and attach and extravasate out of the vessels to form secondary tumors at distant organs. This makes extravasation a critical step of the metastatic cascade. Herein, with a focus on triple-negative breast cancer, the role that the prospective secondary tumor microenvironment's mechanical properties play in circulating tumor cells' extravasation is reviewed. Specifically, the effects of the physically regulated vascular endothelial glycocalyx barrier element, vascular flow factors, and subendothelial extracellular matrix mechanical properties on cancer cell extravasation are examined. The ultimate goal of this review is to clarify the physical mechanisms that drive triple-negative breast cancer extravasation, as these mechanisms may be potential new targets for anti-metastasis therapy.


Assuntos
Glicocálix , Neoplasias de Mama Triplo Negativas , Microambiente Tumoral , Glicocálix/metabolismo , Glicocálix/patologia , Humanos , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Feminino , Microambiente Tumoral/fisiologia , Animais , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Metástase Neoplásica , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia
3.
BMC Genomics ; 25(1): 12, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166720

RESUMO

BACKGROUND: GRAS is a family of plant-specific transcription factors (TFs) that play a vital role in plant growth and development and response to adversity stress. However, systematic studies of the GRAS TF family in kiwifruit have not been reported. RESULTS: In this study, we used a bioinformatics approach to identify eighty-six AcGRAS TFs located on twenty-six chromosomes and phylogenetic analysis classified them into ten subfamilies. It was found that the gene structure is relatively conserved for these genes and that fragmental duplication is the prime force for the evolution of AcGRAS genes. However, the promoter region of the AcGRAS genes mainly contains cis-acting elements related to hormones and environmental stresses, similar to the results of GO and KEGG enrichment analysis, suggesting that hormone signaling pathways of the AcGRAS family play a vital role in regulating plant growth and development and adversity stress. Protein interaction network analysis showed that the AcGRAS51 protein is a relational protein linking DELLA, SCR, and SHR subfamily proteins. The results demonstrated that 81 genes were expressed in kiwifruit AcGRAS under salt stress, including 17 differentially expressed genes, 13 upregulated, and four downregulated. This indicates that the upregulated AcGRAS55, AcGRAS69, AcGRAS86 and other GRAS genes can reduce the salt damage caused by kiwifruit plants by positively regulating salt stress, thus improving the salt tolerance of the plants. CONCLUSIONS: These results provide a theoretical basis for future exploration of the characteristics and functions of more AcGRAS genes. This study provides a basis for further research on kiwifruit breeding for resistance to salt stress. RT-qPCR analysis showed that the expression of 3 AcGRAS genes was elevated under salt stress, indicating that AcGRAS exhibited a specific expression pattern under salt stress conditions.


Assuntos
Genoma de Planta , Fatores de Transcrição , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Filogenia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/metabolismo , Melhoramento Vegetal , Estresse Fisiológico/genética , Tolerância ao Sal
4.
BMC Genomics ; 25(1): 468, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745142

RESUMO

BACKGROUND: Plant-specific TIFY proteins are widely found in terrestrial plants and play important roles in plant adversity responses. Although the genome of loquat at the chromosome level has been published, studies on the TIFY family in loquat are lacking. Therefore, the EjTIFY gene family was bioinformatically analyzed by constructing a phylogenetic tree, chromosomal localization, gene structure, and adversity expression profiling in this study. RESULTS: Twenty-six EjTIFY genes were identified and categorized into four subfamilies (ZML, JAZ, PPD, and TIFY) based on their structural domains. Twenty-four EjTIFY genes were irregularly distributed on 11 of the 17 chromosomes, and the remaining two genes were distributed in fragments. We identified 15 covariate TIFY gene pairs in the loquat genome, 13 of which were involved in large-scale interchromosomal segmental duplication events, and two of which were involved in tandem duplication events. Many abiotic stress cis-elements were widely present in the promoter region. Analysis of the Ka/Ks ratio showed that the paralogous homologs of the EjTIFY family were mainly subjected to purifying selection. Analysis of the RNA-seq data revealed that a total of five differentially expressed genes (DEGs) were expressed in the shoots under gibberellin treatment, whereas only one gene was significantly differentially expressed in the leaves; under both low-temperature and high-temperature stresses, there were significantly differentially expressed genes, and the EjJAZ15 gene was significantly upregulated under both low- and high-temperature stress. RNA-seq and qRT-PCR expression analysis under salt stress conditions revealed that EjJAZ2, EjJAZ4, and EjJAZ9 responded to salt stress in loquat plants, which promoted resistance to salt stress through the JA pathway. The response model of the TIFY genes in the jasmonic acid pathway under salt stress in loquat was systematically summarized. CONCLUSIONS: These results provide a theoretical basis for exploring the characteristics and functions of additional EjTIFY genes in the future. This study also provides a theoretical basis for further research on breeding for salt stress resistance in loquat. RT-qPCR analysis revealed that the expression of one of the three EjTIFY genes increased and the expression of two decreased under salt stress conditions, suggesting that EjTIFY exhibited different expression patterns under salt stress conditions.


Assuntos
Eriobotrya , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Eriobotrya/genética , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Genoma de Planta , Cromossomos de Plantas/genética
5.
Biochem Cell Biol ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39116458

RESUMO

Diabetic nephropathy (DN) is one of the most common complications of diabetes. Our previous study showed that CD38 knockout (CD38KO) mice had protective effects on many diseases. However, the roles and mechanisms of CD38 in DN remain unknown. Here, DN mice were generated by HFD feeding plus streptozotocin (STZ) injection in male CD38KO and CD38flox mice. Mesangial cells (SV40 MES 13 cells) were used to mimic the injury of DN with palmitic acid (PA) treatment in vitro. Our results showed that CD38 expression was significantly increased in kidney of diabetic CD38flox mice and SV40 MES 13 cells treated with PA. CD38KO mice were significantly resistant to diabetes-induced renal injury. Moreover, CD38 deficiency markedly decreased HFD/STZ-induced lipid accumulation, fibrosis and oxidative stress in kidney tissue. In contrast, overexpression of CD38 aggravated PA-induced lipid accumulation and oxidative stress. CD38 deficiency increased expression of SIRT3, while overexpression of CD38 decreased its expression. More importantly, 3-TYP, an inhibitor of SIRT3, significantly enhanced PA-induced lipid accumulation and oxidative stress in CD38 overexpressing cell lines. In conclusion, our results demonstrated that CD38 deficiency prevented DN by inhibiting lipid accumulation and oxidative stress through activation of the SIRT3 pathway.

6.
BMC Plant Biol ; 24(1): 833, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243055

RESUMO

BACKGROUND: 'Hongyang' kiwifruit (Actinidia chinensis cv 'Hongyang') is a high-quality variety of A. chinensis with the advantages of high yield, early ripening, and high stress tolerance. Studies have confirmed that the Shaker K+ genes family is involved in plant uptake and distribution of potassium (K+). RESULTS: Twenty-eight Shaker genes were identified and analyzed from the 'Hongyang' kiwifruit (A. chinensis cv 'Hongyang') genome. Subcellular localization results showed that more than one-third of the AcShaker genes were on the cell membrane. Phylogenetic analysis indicated that the AcShaker genes were divided into six subfamilies (I-VI). Conservative model, gene structure, and structural domain analyses showed that AcShaker genes of the same subfamily have similar sequence features and structure. The promoter cis-elements of the AcShaker genes were classified into hormone-associated cis-elements and environmentally stress-associated cis-elements. The results of chromosomal localization and duplicated gene analysis demonstrated that AcShaker genes were distributed on 18 chromosomes, and segmental duplication was the prime mode of gene duplication in the AcShaker family. GO enrichment analysis manifested that the ion-conducting pathway of the AcShaker family plays a crucial role in regulating plant growth and development and adversity stress. Compared with the transcriptome data of the control group, all AcShaker genes were expressed under low-K+stress, and the expression differences of three genes (AcShaker15, AcShaker17, and AcShaker22) were highly significant. The qRT-PCR results showed a high correlation with the transcriptome data, which indicated that these three differentially expressed genes could regulate low-K+ stress and reduce K+ damage in kiwifruit plants, thus improving the resistance to low-K+ stress. Comparison between the salt stress and control transcriptomic data revealed that the expression of AcShaker11 and AcShaker18 genes was significantly different and lower under salt stress, indicating that both genes could be involved in salt stress resistance in kiwifruit. CONCLUSION: The results showed that 28 AcShaker genes were identified and all expressed under low K+ stress, among which AcShaker22 was differentially and significantly upregulated. The AcShaker22 gene can be used as a candidate gene to cultivate new varieties of kiwifruit resistant to low K+ and provide a reference for exploring more properties and functions of the AcShaker genes.


Assuntos
Actinidia , Potássio , Superfamília Shaker de Canais de Potássio , Actinidia/genética , Frutas/genética , Frutas/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Potássio/metabolismo , Superfamília Shaker de Canais de Potássio/genética , Superfamília Shaker de Canais de Potássio/metabolismo , Estresse Fisiológico/genética
7.
Small ; 20(10): e2305678, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875729

RESUMO

Small-scale and flexible acoustic probes are more desirable for exquisite objects like human bodies and complex-shaped components than conventional rigid ones. Herein, a thin-film flexible acoustic sensor (FA-TES) that can detect ultra-broadband acoustic signals in multiple applications is proposed. The device consists of two thin copper-coated polyvinyl chloride films, which are stimulated by acoustic waves and contact each other to generate the triboelectric signal. Interlocking nanocolumn arrays fabricated on the friction surfaces are regarded as a highly adaptive spacer enabling this device to respond to ultra-broadband acoustic signals (100 Hz-4 MHz) and enhance sensor sensitivity for film weak vibration. Benefiting from the characteristics of high shape adaptability and ultrawide response range, the FA-TES can precisely sense human physiological sounds and voice (≤10 kHz) for laryngeal health monitoring and interaction in real-time. Moreover, the FA-TES flexibly arranged on a 3D-printed vertebra model can effectively and accurately diagnose the inner defect by ultrasonic testing (≥1 MHz). It envisions that this work can provide new ideas for flexible acoustic sensor designs and optimize real-time acoustic detections of human bodies and complex components.


Assuntos
Acústica , Ultrassom , Humanos , Ultrassonografia , Som , Fricção
8.
J Transl Med ; 22(1): 743, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107765

RESUMO

BACKGROUND: Severe heart failure (HF) has a higher mortality during vulnerable period while targeted predictive tools, especially based on drug exposures, to accurately assess its prognoses remain largely unexplored. Therefore, this study aimed to utilize drug information as the main predictor to develop and validate survival models for severe HF patients during this period. METHODS: We extracted severe HF patients from the MIMIC-IV database (as training and internal validation cohorts) as well as from the MIMIC-III database and local hospital (as external validation cohorts). Three algorithms, including Cox proportional hazards model (CoxPH), random survival forest (RSF), and deep learning survival prediction (DeepSurv), were applied to incorporate the parameters (partial hospitalization information and exposure durations of drugs) for constructing survival prediction models. The model performance was assessed mainly using area under the receiver operator characteristic curve (AUC), brier score (BS), and decision curve analysis (DCA). The model interpretability was determined by the permutation importance and Shapley additive explanations values. RESULTS: A total of 11,590 patients were included in this study. Among the 3 models, the CoxPH model ultimately included 10 variables, while RSF and DeepSurv models incorporated 24 variables, respectively. All of the 3 models achieved respectable performance metrics while the DeepSurv model exhibited the highest AUC values and relatively lower BS among these models. The DCA also verified that the DeepSurv model had the best clinical practicality. CONCLUSIONS: The survival prediction tools established in this study can be applied to severe HF patients during vulnerable period by mainly inputting drug treatment duration, thus contributing to optimal clinical decisions prospectively.


Assuntos
Insuficiência Cardíaca , Modelos de Riscos Proporcionais , Humanos , Insuficiência Cardíaca/mortalidade , Insuficiência Cardíaca/tratamento farmacológico , Feminino , Masculino , Idoso , Reprodutibilidade dos Testes , Prognóstico , Análise de Sobrevida , Pessoa de Meia-Idade , Curva ROC , Algoritmos , Área Sob a Curva , Bases de Dados Factuais , Aprendizado Profundo , Índice de Gravidade de Doença
9.
Magn Reson Med ; 91(6): 2403-2416, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38263908

RESUMO

PURPOSE: The study aims to assess the potential of referenceless methods of EPI ghost correction to accelerate the acquisition of in vivo diffusion tensor cardiovascular magnetic resonance (DT-CMR) data using both computational simulations and data from in vivo experiments. METHODS: Three referenceless EPI ghost correction methods were evaluated on mid-ventricular short axis DT-CMR spin echo and STEAM datasets from 20 healthy subjects at 3T. The reduced field of view excitation technique was used to automatically quantify the Nyquist ghosts, and DT-CMR images were fit to a linear ghost model for correction. RESULTS: Numerical simulation showed the singular value decomposition (SVD) method is the least sensitive to noise, followed by Ghost/Object method and entropy-based method. In vivo experiments showed significant ghost reduction for all correction methods, with referenceless methods outperforming navigator methods for both spin echo and STEAM sequences at b = 32, 150, 450, and 600 smm - 2 $$ {\mathrm{smm}}^{-2} $$ . It is worth noting that as the strength of the diffusion encoding increases, the performance gap between the referenceless method and the navigator-based method diminishes. CONCLUSION: Referenceless ghost correction effectively reduces Nyquist ghost in DT-CMR data, showing promise for enhancing the accuracy and efficiency of measurements in clinical practice without the need for any additional reference scans.


Assuntos
Imagem Ecoplanar , Processamento de Imagem Assistida por Computador , Humanos , Imagem Ecoplanar/métodos , Processamento de Imagem Assistida por Computador/métodos , Razão Sinal-Ruído , Imagens de Fantasmas , Espectroscopia de Ressonância Magnética , Artefatos , Encéfalo , Algoritmos
10.
J Cardiovasc Magn Reson ; 26(2): 101052, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38936803

RESUMO

BACKGROUND: In-vivo diffusion tensor cardiovascular magnetic resonance (DT-CMR) is an emerging technique for microstructural tissue characterization in the myocardium. Most studies are performed at 3T, where higher signal-to-noise ratio (SNR) should benefit this signal-starved method. However, a few studies have suggested that DT-CMR is possible at 1.5T, where echo planar imaging artifacts may be less severe and 1.5T hardware is more widely available. METHODS: We recruited 20 healthy volunteers and performed mid-ventricular short-axis DT-CMR at 1.5T and 3T. Acquisitions were performed at peak systole and end-diastole using both stimulated echo acquisition mode (STEAM) and motion-compensated spin-echo (MCSE) sequences at matched spatial resolutions. DT-CMR parameters were averaged over the left ventricle and compared between 1.5T and 3T sequences using both datasets with and without the blow reference data included. RESULTS: Eleven (1.5T) and 12 (3T) diastolic MCSE acquisitions were rejected as the helix angle (HA) demonstrated <50% normal appearance circumferentially or the acquisition was abandoned due to poor image quality; a maximum of one acquisition was rejected for other datasets. Subjective HA map quality was significantly better at 3T than 1.5T for STEAM (p < 0.05), but not for MCSE and other DT-CMR quality measures were consistent with improvements in STEAM at 3T over 1.5T. When blow data were excluded, no significant differences in mean diffusivity were observed between field strengths, but fractional anisotropy was significantly higher at 1.5T than 3T for STEAM systole (p < 0.05). Absolute second eigenvector orientation (E2A, sheetlet angle) was significantly higher at 1.5T than 3T for MCSE systole and STEAM diastole, but significantly lower for STEAM systole (all p < 0.05). Transmural HA distribution was less steep at 1.5T than 3T for STEAM diastole data (p < 0.05). SNR was higher at 3T than 1.5T for all acquisitions (p < 0.05). CONCLUSION: While 3T provides benefits in terms of SNR, both STEAM and MCSE can be performed at 1.5T. However, MCSE is unreliable in diastole at both field strengths and STEAM benefits from the improved SNR at 3T over 1.5T. Future clinical research studies may be able to leverage the wider availability of 1.5T CMR hardware where MCSE acquisitions are desirable.

11.
Infection ; 52(3): 1063-1072, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38265608

RESUMO

BACKGROUND AND PURPOSE: The need for dose adjustment of caspofungin in patients with hepatic impairment is controversial, especially for those with Child-Pugh B or C cirrhosis. The purpose of this study was to investigate the safety and efficacy of standard-dose caspofungin administration in Child-Pugh B and C cirrhotic patients in a real-world clinical setting. PATIENTS AND METHODS: The electronic medical records of 258 cirrhotic patients, including 67 Child-Pugh B patients and 191 Child-Pugh C patients, who were treated with standard-dose of caspofungin at the Second Affiliated Hospital of Chongqing Medical University, China, from March 2018 to June 2023 were reviewed retrospectively. The white blood cells (WBC), hepatic, renal and coagulation function results before administration and post administration on days 7, 14 and 21 were collected, and the efficacy was assessed in all patients at the end of caspofungin therapy. RESULTS: Favorable responses were achieved in 137 (53.1%) patients while 34 (13.2%) patients died. We observed that some patients experienced an increase of prothrombin time (PT) or international normalized ratio (INR), or a decrease of WBC, but no exacerbation of hepatic or renal dysfunction were identified and no patient required dose interruption or adjustment because of an adverse drug reaction during treatment with caspofungin. CONCLUSIONS: Standard-dose of caspofungin can be safely and effectively used in patients with Child-Pugh B or C cirrhosis, and we appealed to re-assess the most suitable dosing regimen in this population to avoid a potential subtherapeutic exposure.


Assuntos
Antifúngicos , Caspofungina , Cirrose Hepática , Humanos , Caspofungina/uso terapêutico , Masculino , Feminino , Pessoa de Meia-Idade , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/complicações , Estudos Retrospectivos , Idoso , Antifúngicos/uso terapêutico , Antifúngicos/efeitos adversos , Antifúngicos/administração & dosagem , Resultado do Tratamento , Adulto , China
12.
Environ Sci Technol ; 58(5): 2313-2322, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38266164

RESUMO

Mineral adsorption-induced molecular fractionation of dissolved organic matter (DOM) affects the composition of both DOM and OM adsorbed and thus stabilized by minerals. However, it remains unclear what mineral properties control the magnitude of DOM fractionation. Using a combined technique approach that leverages the molecular composition identified by ultrahigh resolution 21 T Fourier transform ion cyclotron resonance mass spectrometry and adsorption isotherms, we catalogue the compositional differences that occur at the molecular level that results in fractionation due to adsorption of Suwannee River fulvic acid on aluminum (Al) and iron (Fe) oxides and a phyllosilicate (allophane) species of contrasting properties. The minerals of high solubility (i.e., amorphous Al oxide, boehmite, and allophane) exhibited much stronger DOM fractionation capabilities than the minerals of low solubility (i.e., gibbsite and Fe oxides). Specifically, the former released Al3+ to solution (0.05-0.35 mM) that formed complexes with OM and likely reduced the surface hydrophobicity of the mineral-OM assemblage, thus increasing the preference for adsorbing polar DOM molecules. The impacts of mineral solubility are exacerbated by the fact that interactions with DOM also enhance metal release from minerals. For sparsely soluble minerals, the mineral surface hydrophobicity, instead of solubility, appeared to be the primary control of their DOM fractionation power. Other chemical properties seemed less directly relevant than surface hydrophobicity and solubility in fractionating DOM.


Assuntos
Matéria Orgânica Dissolvida , Minerais , Adsorção , Solubilidade , Minerais/química , Alumínio , Óxidos
13.
Environ Toxicol ; 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39082229

RESUMO

Acrylamide (AAM), a compound extensively utilized in various industrial applications, has been reported to induce toxic effects across multiple tissues in living organisms. Despite its widespread use, the impact of AAM on ovarian function and the mechanisms underlying these effects remain poorly understood. Here, we established an AAM-exposed mouse toxicological model using 21 days of intragastric AAM administration. AAM exposure decreased ovarian coefficient and impaired follicle development. Further investigations revealed AAM would trigger apoptosis and disturb tricarboxylic acid cycle in ovarian tissue, thus affecting mitochondrial electron transport function. Moreover, AAM exposure decreased oocyte and embryo development potential, mechanically associated with pericentrin and phosphorylated Aurora A cluster failure, leading to meiotic spindle assembly defects. Collectively, these results suggest that AAM exposure may lead to apoptosis, glucose metabolic disorders, and mitochondrial dysfunction in ovary tissue, ultimately compromising oocyte quality.

14.
Am J Physiol Cell Physiol ; 324(2): C488-C504, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36440856

RESUMO

Endothelium health is essential to the regulation of physiological vascular functions. Because of the critical capability of endothelial cells (ECs) to sense and transduce chemical and mechanical signals in the local vascular environment, their dysfunction is associated with a vast variety of vascular diseases and injuries, especially atherosclerosis and subsequent cardiovascular diseases. This review describes the mechanotransduction events that are mediated through ECs, the EC subcellular components involved, and the pathways reported to be potentially involved. Up-to-date research efforts involving in vivo animal models and in vitro biomimetic models are also discussed, including their advantages and drawbacks, with recommendations on future modeling approaches to aid the development of novel therapies targeting atherosclerosis and related cardiovascular diseases.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Animais , Células Endoteliais/metabolismo , Mecanotransdução Celular/fisiologia , Doenças Cardiovasculares/metabolismo , Endotélio Vascular/metabolismo , Aterosclerose/metabolismo , Estresse Mecânico
15.
AJR Am J Roentgenol ; 220(6): 817-825, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36752371

RESUMO

BACKGROUND. Abbreviated protocols could allow wider adoption of MRI in patients undergoing breast cancer neoadjuvant chemotherapy (NAC). However, abbreviated MRI has been explored primarily in screening settings. OBJECTIVE. The purpose of this article was to compare diagnostic performance of abbreviated MRI and full-protocol MRI for evaluation of breast cancer NAC response, stratifying by radiologists' breast imaging expertise. METHODS. This retrospective study included 203 patients with breast cancer (mean age, 52.1 ± 11.2 [SD] years) from two hospitals who underwent MRI before NAC initiation and after NAC completion before surgical resection from March 2017 to April 2021. Abbreviated MRI was extracted from full-protocol MRI and included the axial T2-weighted sequence and precontrast and single early postcontrast T1-weighted sequences. Three general radiologists and three breast radiologists independently interpreted abbreviated and full-protocol MRI in separate sessions, identifying enhancing lesions to indicate residual tumor and measuring lesion size. The reference standard was presence and size of residual tumor on pathologic assessment of post-NAC surgical specimens. RESULTS. A total of 50 of 203 patients had pathologic complete response (pCR). Intraobserver and interobserver agreement for abbreviated and full-protocol MRI for general and breast radiologists ranged from substantial to nearly perfect (κ = 0.70-0.81). Abbreviated MRI compared with full-protocol MRI showed no significant difference for general radiologists in sensitivity (54.7% vs 57.3%, p > .99), specificity (92.8% vs 95.6%, p = .29), or accuracy (83.4% vs 86.2%, p = .30), nor for breast radiologists in sensitivity (60.0% vs 61.3%, p > .99), specificity (94.6% vs 97.4%, p = .22), or accuracy (86.0% vs 88.5%, p = .30). Sensitivity, specificity, and accuracy were not significantly different between protocols for any reader individually (p > .05). Mean difference in residual tumor size on MRI relative to pathology for abbreviated protocol ranged for general radiologists from -0.19 to 0.03 mm and for breast radiologists from -0.15 to -0.05 mm, and for full protocol ranged for general radiologists from 0.57 to 0.65 mm and for breast radiologists from 0.66 to 0.79 mm. CONCLUSION. Abbreviated compared with full-protocol MRI showed similar intraobserver and interobserver agreement and no significant difference in diagnostic performance. Full-protocol MRI but not abbreviated MRI slightly overestimated pathologic tumor sizes. CLINICAL IMPACT. Abbreviated protocols may facilitate use of MRI for post-NAC response assessment by general and breast radiologists.


Assuntos
Neoplasias da Mama , Humanos , Adulto , Pessoa de Meia-Idade , Feminino , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Estudos Retrospectivos , Terapia Neoadjuvante , Neoplasia Residual , Imageamento por Ressonância Magnética/métodos
16.
Nanotechnology ; 34(15)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36626828

RESUMO

2D layered photocatalysts with proper electronic structure have sparked much attention in the field of visible-light photocatalysis for H2production. Herein, by simply calcining the mixture of ultrathin g-C3N4(CNN) and NaBH4, heteroatom B and N defect were simultaneously introduced into g-C3N4. The obtained modified g-C3N4(BDCNN) was further coupled with 2D flower-like CdS nanosheet. The optimal 2D/2D BDCNN/CdS-15% heterojunction behaved ideal photocatalytic activity for H2revolution by water splitting, and the highest H2revolution rate was as high as 1013.8µmol g-1h-1, which was 6.7 times, 2 times, and 5.8 times of the corresponding values of pristine CNN, BDCNN and CdS respectively. It was evidenced that the band structure of 2D/2D BDCNN/CdS-15% was well tuned for better visible-light adsorption and higher separation efficiency of photo-induced carriers for enhancing H2revolution performance. The achievement in this study provided informative principles for exploring g-C3N4based heterojunctions with higher H2-production performance.

17.
Environ Sci Technol ; 57(1): 730-740, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36538415

RESUMO

Manganese (Mn) exists as Mn(II), Mn(III), or Mn(IV) in soils, and the Mn oxidation state controls the roles of Mn in numerous environmental processes. However, the variations of Mn oxidation states with climate remain unknown. We determined the Mn oxidation states in highly weathered bulk volcanic soils (primary minerals free) across two rainfall gradients covering mean annual precipitation (MAP) of 0.25-5 m in the Hawaiian Islands. With increasing MAP, the soil redox conditions generally shifted from oxic to suboxic and to anoxic despite fluctuating at each site; concurrently, the proportions of Mn(IV) and Mn(II) decreased and increased, respectively. Mn(III) was low at both low and high MAP, but accumulated substantially, up to 80% of total Mn, in soils with prevalent suboxic conditions at intermediate MAP. Mn(III) was likely hosted in Mn(III,IV) and iron(III) oxides or complexed with organic matter, and its distribution among these hosts varied with soil redox potentials and soil pH. Soil redox conditions and rainfall-driven leaching jointly controlled exchangeable Mn(II) in soils, with its concentration peaking at intermediate MAP. The Mn redox chemistry was at disequilibrium, with the oxidation states correlating with long-term average soil redox potentials better than with soil pH. The soil redox conditions likely fluctuated between oxic and anoxic conditions more frequently at intermediate than at low and high MAP, creating biogeochemical hot spots where Mn, Fe, and other redox-sensitive elements may be actively cycled.


Assuntos
Compostos Férricos , Manganês , Manganês/análise , Solo , Ferro , Oxirredução
18.
Kidney Blood Press Res ; 48(1): 338-346, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37040725

RESUMO

INTRODUCTION: Chronic kidney diseases (CKDs) are prevalent in older people, and renal pathological manifestations are important for diagnosis, treatment, and prognosis. However, the long-term survival outcome and risk factors for older CKD patients with different pathological types are not fully understood and need to be further investigated. METHODS: Medical data were recorded and all-cause mortality was followed up in patients who underwent renal biopsy diagnosed in Guangdong Provincial People's Hospital from 2005 to 2015. Kaplan-Meier analysis was used to identify the incidence of survival outcomes. Multivariate Cox regression models and nomograms were applied to analyze pathological types and other factors for overall survival outcomes. RESULTS: 368 cases were included and the median follow-up was 85 (46.5, 111) months. Overall mortality was 35.6%. The highest mortality was in the mesangioproliferative glomerulonephritis (MPGN) group (88.9%), followed by amyloidosis (AMY) group (84.6%), and the lowest mortality was in the minimal change disease (MCD) group (21.9%). Moreover, multivariate Cox regression model showed that survival times of MPGN {hazard ratio (HR) = 8.215 (95% confidence interval [CI]: 2.735-24.674), p < 0.001} and AMY (HR = 6.130 [95% CI: 2.219-16.94], p < 0.001) were significantly shorter than MCD. In addition, age, lower baseline estimated glomerular filtration rate (eGFR), history of chronic obstructive pulmonary disease (COPD) and cerebrovascular accidents (CVA)/transient ischemic attack (TIA), MPGN, and AMY were independent risk factors for the mortality of older patients with CKD. CONCLUSION: The long-term survival outcome of older CKD patients showed differences among different pathological types, and MPGN, AMY, age, baseline eGFR, CVA/TIA, and COPD were independent predictors for mortality.


Assuntos
Glomerulonefrite , Ataque Isquêmico Transitório , Doença Pulmonar Obstrutiva Crônica , Insuficiência Renal Crônica , Acidente Vascular Cerebral , Humanos , Idoso , Ataque Isquêmico Transitório/epidemiologia , Rim , Prognóstico , Acidente Vascular Cerebral/complicações , Fatores de Risco , Doença Pulmonar Obstrutiva Crônica/complicações , Taxa de Filtração Glomerular , Estudos Retrospectivos
19.
Bioorg Chem ; 131: 106329, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36565674

RESUMO

A series of lathyrane-type Euphorbia diterpene derivatives featured 3R configuration (H-3ß) were synthesized from natural rich Euphorbia factor L3via modified Mitsunobu reaction based on configuration inversion strategy. The antiproliferation activity and MDR reversal ability of the lathyrane derivatives were evaluated, and the most synthesized compounds showed moderate or strong potencies. Among them, diterpenes 21 (IC50 values of 2.6, 5.2 and 13.1 µM, respectively) and 25 (IC50 values of 5.5, 8.6 and 1.3 µM, respectively) presented the strong cytotoxicity against MCF-7, 4 T1 and HepG2 cells. Meanwhile, derivative 25 exhibited excellent MDR reversal ability with the reversal fold of 16.1 higher than that of verapamil. The cellular thermal shift assay and molecular docking proved direct engagement of diterpene 25 to ABCB1, suggesting 25 could be a promising MDR modulator. Furthermore, the preliminary SARs of these diterpenes were also discussed.


Assuntos
Antineoplásicos , Diterpenos , Euphorbia , Humanos , Linhagem Celular Tumoral , Diterpenos/síntese química , Diterpenos/farmacologia , Euphorbia/química , Células Hep G2 , Simulação de Acoplamento Molecular , Estrutura Molecular , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia
20.
Can J Physiol Pharmacol ; 101(7): 369-381, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37192549

RESUMO

Obesity is a metabolic syndrome characterized by abnormal lipid deposition and energy imbalance. CD38 is a single-chain transmembrane glycoprotein widely expressed in a variety of cell types. The roles of skeletal muscle and brown fat in CD38 deficiency under HFD-induced obesity remain unknown. In this study, we established obesity model with HFD and examined the changes in metabolites with metabonomics. Our results showed that CD38 expression was increased in muscle and brown fat after HFD treatment. Moreover, the results of metabonomics showed that CD38 deficiency significantly altered the metabolites in energy metabolism, cofactor generation, and redox homeostasis. Furthermore, CD38 deficiency reduced the expressions of NADPH oxidase 2 and FASN in mRNA level. We found that the expressions of Sirt1, Sirt3, and PGC1α were upregulated in CD38-deficient muscle tissue. In brown fat, the Sirt1-3, cell death inducing DFFA-like effector A, ELOVL3, and Dio2 expressions were increased in CD38-deficient mice. Our results showed the uncoupling protein 1 expression was upregulated. And NAD+ supplementation increased the expression of Sirt1 and PGC1α after palmitic acid treatment. Taken together, our results demonstrated that the protection of CD38 deficiency on HFD-induced obesity was related to the inhibition of oxidative stress and increasing energy expenditure via activating NAD+/Sirtuins signaling pathways in muscle and brown fat.


Assuntos
Tecido Adiposo Marrom , NAD , Animais , Camundongos , Tecido Adiposo Marrom/metabolismo , Dieta Hiperlipídica , Metabolismo Energético , Camundongos Endogâmicos C57BL , Músculo Esquelético/metabolismo , NAD/metabolismo , Obesidade/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo
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