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1.
Cell Stem Cell ; 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38565140

RESUMO

Neonatal spinal cord tissues exhibit remarkable regenerative capabilities as compared to adult spinal cord tissues after injury, but the role of extracellular matrix (ECM) in this process has remained elusive. Here, we found that early developmental spinal cord had higher levels of ECM proteins associated with neural development and axon growth, but fewer inhibitory proteoglycans, compared to those of adult spinal cord. Decellularized spinal cord ECM from neonatal (DNSCM) and adult (DASCM) rabbits preserved these differences. DNSCM promoted proliferation, migration, and neuronal differentiation of neural progenitor cells (NPCs) and facilitated axonal outgrowth and regeneration of spinal cord organoids more effectively than DASCM. Pleiotrophin (PTN) and Tenascin (TNC) in DNSCM were identified as contributors to these abilities. Furthermore, DNSCM demonstrated superior performance as a delivery vehicle for NPCs and organoids in spinal cord injury (SCI) models. This suggests that ECM cues from early development stages might significantly contribute to the prominent regeneration ability in spinal cord.

2.
Nutrients ; 16(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38474792

RESUMO

Colostrum basic protein (CBP) is a trace protein extracted from bovine colostrum. Previous studies have shown that CBP can promote bone cell differentiation and increase bone density. However, the mechanism by which CBP promotes bone activity remains unclear. This study investigated the mechanism of the effect of CBP on bone growth in mice following dietary supplementation of CBP at doses that included 0.015%, 0.15%, 1.5%, and 5%. Compared with mice fed a normal diet, feeding 5% CBP significantly enhanced bone rigidity and improved the microstructure of bone trabeculae. Five-percent CBP intake triggered significant positive regulation of calcium metabolism in the direction of bone calcium accumulation. The expression levels of paracellular calcium transport proteins CLDN2 and CLDN12 were upregulated nearly 1.5-fold by 5% CBP. We conclude that CBP promotes calcium absorption in mice by upregulating the expression of the calcium-transporting paracellular proteins CLND2 and CLND12, thereby increasing bone density and promoting bone growth. Overall, CBP contributes to bone growth by affecting calcium metabolism.


Assuntos
Cálcio , Colostro , Gravidez , Feminino , Animais , Camundongos , Bovinos , Cálcio/metabolismo , Colostro/metabolismo , Cálcio da Dieta/metabolismo , Osso e Ossos/metabolismo , Desenvolvimento Ósseo , Densidade Óssea , Proteínas na Dieta/farmacologia
3.
iScience ; 27(4): 109473, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38551007

RESUMO

This paper proposes a Pontryagin's minimum principle (PMP) energy management strategy (EMS) based on driving cycle recognition for fuel cell vehicle powertrains, aiming to minimize hydrogen consumption and fuel cell degradation. Firstly, the neural network-based driving cycle recognizer is optimized using the tuna swarm optimization (TSO) algorithm and trained under four typical driving cycles. Then, the optimal co-state variables for the four driving cycles are obtained by iteration. Finally, the co-state variables are dynamically updated based on real-time driving cycle recognition results. Comparative analysis demonstrates that the PMP-DCR effectively improves fuel cell lifetime and vehicle economy under short-distance driving cycles. Based on the combined driving cycle, the proposed PMP-DCR EMS exhibits similar economy performance to optimal dynamic programming (DP) EMS, reducing equivalent hydrogen consumption by 13.8% and 9.2%, and decreasing fuel cell degradation rates by 93% and 8.7% in comparison to the conventional power-following and PMP EMS, respectively.

4.
Int J Mol Sci ; 25(6)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38542450

RESUMO

Lung aging triggers the onset of various chronic lung diseases, with alveolar repair being a key focus for alleviating pulmonary conditions. The regeneration of epithelial structures, particularly the differentiation from type II alveolar epithelial (AT2) cells to type I alveolar epithelial (AT1) cells, serves as a prominent indicator of alveolar repair. Nonetheless, the precise role of aging in impeding alveolar regeneration and its underlying mechanism remain to be fully elucidated. Our study employed histological methods to examine lung aging effects on structural integrity and pathology. Lung aging led to alveolar collapse, disrupted epithelial structures, and inflammation. Additionally, a relative quantification analysis revealed age-related decline in AT1 and AT2 cells, along with reduced proliferation and differentiation capacities of AT2 cells. To elucidate the mechanisms underlying AT2 cell functional decline, we employed transcriptomic techniques and revealed a correlation between inflammatory factors and genes regulating proliferation and differentiation. Furthermore, a D-galactose-induced senescence model in A549 cells corroborated our omics experiments and confirmed inflammation-induced cell cycle arrest and a >30% reduction in proliferation/differentiation. Physiological aging-induced chronic inflammation impairs AT2 cell functions, hindering tissue repair and promoting lung disease progression. This study offers novel insights into chronic inflammation's impact on stem cell-mediated alveolar regeneration.


Assuntos
Células Epiteliais Alveolares , Pulmão , Humanos , Células Epiteliais Alveolares/metabolismo , Células Cultivadas , Pulmão/metabolismo , Diferenciação Celular/fisiologia , Inflamação/metabolismo
5.
Sensors (Basel) ; 24(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38400297

RESUMO

To enhance the safety and reliability of fuel cell vehicles, a remote monitoring system based on 5th generation (5G) mobile networks and controller area networks (CANs) was designed, and a random forest (RF) algorithm for the fault diagnosis for eight typical malfunctions of its powertrain system was incorporated. Firstly, the information on the powertrain system was obtained through a 5G-based monitoring terminal, and the Alibaba Cloud IoT platform was utilized for data storage and remote monitoring. Secondly, a fault diagnosis model based on the RF algorithm was constructed for fault classification; its parameters were optimized with a genetic algorithm (GA), and it was applied on the Alibaba Cloud PAI platform. Finally, the performance of the proposed RF fault diagnosis model was evaluated by comparing it with three other classification models: random search conditioning, grid search conditioning, and Bayesian optimization. Results show that the model accuracy, F1 score, and kappa value of the optimized RF fault classification model are higher than the other three. The model achieves an F1 value of 97.77% in identifying multiple typical faults of the powertrain system, as validated by vehicle malfunction data. The method demonstrates the feasibility of remote monitoring and fault diagnosis for the powertrain system of fuel cell vehicles.

6.
Heliyon ; 10(1): e23352, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38163214

RESUMO

Background: Pulmonary arterial hypertension (PAH) leads to myocardial remodeling, manifesting as mechanical dyssynchrony (M-dys) and electrical dyssynchrony (E-dys), in both right (RV) and left ventricles (LV). However, the impacts of layer-specific intraventricular M-dys on biventricular functions and its association with E-dys in PAH remain unclear. Methods: Seventy-nine newly diagnosed patients with PAH undergoing cardiac magnetic resonance scanning were consecutively recruited between January 2011 and December 2017. The biventricular volumetric and layer-specific intraventricular M-dys were analyzed. The QRS duration z-scores were calculated after adjusting for age and sex. Results: 77.22 % of patients were female (mean age 30.30 ± 9.79 years; median follow-up 5.53 years). Further, 29 (36.71 %) patients succumbed to all-cause mortality by the end of the study. At the baseline, LV layer-specific intraventricular M-dys had apparent transmural gradients compared with RV in the radial and circumferential directions. However, deceased patients lost the transmural gradients. The LV longitudinal strain rate time to late diastolic peak in the myocardial region (LVmyoLSRTTLDPintra) predicted long-term survival. The Kaplan-Meier curve revealed that patients with PAH with LVmyoLSRTTLDPintra <20.01 milliseconds had a worse prognosis. Larger right ventricle (RV) intraventricular M-dys resulted in worse RV ejection fraction. However, larger LV intraventricular M-dys in the late diastolic phase indicated remarkable exercise capacity and higher LV stroke volume index. E-dys and intraventricular M-dys had no direct correlations. Conclusions: The layer-specific intraventricular M-dys had varying impacts on biventricular functions in PAH. PAH patients with LVmyoLSRTTLDPintra <20.01 milliseconds had a worse prognosis. LV intraventricular M-dys in the late diastolic phase needs more attention to precisely evaluate LV function.

7.
Food Funct ; 15(2): 866-880, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38165790

RESUMO

The immune system of infants is partly weak and immature, and supplementation of infant formula can be of vital importance to boost the development of the immune system. Lactoferrin (LF) and osteopontin (OPN) are essential proteins in human milk with immunoregulation function. An increasing number of studies indicate that proteins have interactions with each other in milk, and our previous study found that a ratio of LF : OPN at 1 : 5 (w/w, denoted as LOP) had a synergistic effect on intestinal barrier protection. It remains unknown whether LOP can also exert a stronger effect on immunoregulation. Hence, we used an in vitro model of LPS-induced macrophage inflammation and in vivo models of LPS-induced intestinal inflammation and early life development. We showed that LOP increased the secretion of the granulocyte-macrophage colony-stimulating factor (132%), stem cell factor (167%) and interleukin-3 (176%) in bone marrow cells, as well as thymosin (155%) and interleukin-10 (161%) in the thymus, more than LF or OPN alone during development, and inhibited changes in immune cells and cytokines during the LPS challenge. In addition, analysis of the components of digested proteins in vitro revealed that differentially expressed peptides may provide immunoregulation. Lastly, LOP increased the abundance of Rikenellaceae, Muribaculum, Faecalibaculum, and Elisenbergiella in the cecum content. These results imply that LOP is a potential immunomodifier for infants and offers a new theoretical basis for infant formula innovation.


Assuntos
Lactoferrina , Osteopontina , Lactente , Humanos , Lactoferrina/química , Osteopontina/genética , Osteopontina/metabolismo , Lipopolissacarídeos/metabolismo , Leite Humano/química , Inflamação/metabolismo , Sistema Imunitário/metabolismo
8.
Nat Ecol Evol ; 8(2): 251-266, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38182682

RESUMO

The biodiversity impacts of agricultural deforestation vary widely across regions. Previous efforts to explain this variation have focused exclusively on the landscape features and management regimes of agricultural systems, neglecting the potentially critical role of ecological filtering in shaping deforestation tolerance of extant species assemblages at large geographical scales via selection for functional traits. Here we provide a large-scale test of this role using a global database of species abundance ratios between matched agricultural and native forest sites that comprises 71 avian assemblages reported in 44 primary studies, and a companion database of 10 functional traits for all 2,647 species involved. Using meta-analytic, phylogenetic and multivariate methods, we show that beyond agricultural features, filtering by the extent of natural environmental variability and the severity of historical anthropogenic deforestation shapes the varying deforestation impacts across species assemblages. For assemblages under greater environmental variability-proxied by drier and more seasonal climates under a greater disturbance regime-and longer deforestation histories, filtering has attenuated the negative impacts of current deforestation by selecting for functional traits linked to stronger deforestation tolerance. Our study provides a previously largely missing piece of knowledge in understanding and managing the biodiversity consequences of deforestation by agricultural deforestation.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Filogenia , Florestas , Agricultura
9.
Eur J Radiol ; 170: 111206, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37995514

RESUMO

PURPOSE: To investigate the imaging characteristics and prognostic factors for the long-term survival of Behcet's disease (BD) with arterial involvement. METHODS: In this retrospective study, BD patients with arterial involvement were identified from January 2003 to January 2020. Arterial lesions were detected by ultrasonography, traditional arteriography, and/or computed tomography angiography (CTA). Cox proportional hazards regression analyses were performed to identify the prognostic factors. RESULTS: Totally, 84 BD patients with arterial involvement were identified (73.8 % males). The mean age at BD diagnosis was 39.1 ± 13.1 years. Arterial involvement was the initial manifestation in 33.3 % of the patients, and the median time from BD diagnosis to arterial involvement was 6 (IQR 1-15.5) years for the rest of patients. Systemic artery involvement and pulmonary artery involvement (PAI) were found in 64 and 27 patients, respectively. Approximately 94.0 % (79/84) of the patients had more than one artery involved concurrently or successively during the course of BD. Aneurysm/dilation was the most prevalent lesion in the aorta (76.0 %), while stenosis/occlusion was the main lesion of the coronary artery (90.9 %) and other aortic branches (74.5 %). Pulmonary hypertension was found in 70.4 % (19/27) of patients with PAI. The 5- and 10-year survival rates of BD patients with arterial involvement were 87.4 % and 84.1 %, respectively. Cardiac involvement (HR: 4.34) and pulmonary artery aneurysm/dilation (HR: 4.89) were independently associated with mortality. CONCLUSIONS: Arterial lesions associated with BD usually involve multiple arteries and manifest differently in different types of arteries. Cardiac involvement and pulmonary artery aneurysm/dilation are independent prognostic factors of BD patients with arterial involvement.


Assuntos
Aneurisma , Síndrome de Behçet , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Feminino , Síndrome de Behçet/diagnóstico por imagem , Seguimentos , Estudos Retrospectivos , Prognóstico , Artéria Pulmonar/diagnóstico por imagem
10.
FEBS J ; 291(5): 986-1007, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38037211

RESUMO

Photoreceptor apoptosis is the main pathological feature of retinal degenerative diseases; however, the underlying molecular mechanism has not been elucidated. Recent studies have shown that N-myc downstream regulated gene 2 (NDRG2) exerts a neuroprotective effect on the brain and spinal cord. In addition, our previous studies have confirmed that NDRG2 is expressed in mouse retinal photoreceptors and counteracts N-methyl-N-nitrosourea (MNU)-induced apoptosis. However, the underlying molecular mechanism remains unclear. In this study, we observed that the expression of NDRG2 was not only significantly inhibited in photoreceptors after MNU treatment but also after hydrogen peroxide treatment, and photoreceptor apoptosis was alleviated or aggravated after overexpression or knockdown of NDRG2 in the 661W photoreceptor cell line, respectively. The apoptosis inhibitor Z-VAD-FMK rescued photoreceptor apoptosis induced by MNU after NDRG2 knockdown. Next, we screened and identified tissue inhibitor of metalloproteinases 3 (TIMP3) as the downstream molecule of NDRG2 in 661W cells by using quantitative real-time polymerase chain reaction. TIMP3 exerts a neuroprotective effect by inhibiting the expression of matrix metalloproteinases (MMPs). Subsequently, we found that signal transducer and activator of transcription 3 (STAT3) mediated the NDRG2-associated regulation of TIMP3. Finally, we overexpressed NDRG2 in mouse retinal tissues by intravitreally injecting an adeno-associated virus with mouse NDRG2 in vivo. Results showed that NDRG2 upregulated the expression of phospho-STAT3 (p-STAT3) and TIMP3, while suppressing MNU-induced photoreceptor apoptosis and MMP expression. Our findings revealed how NDRG2 regulates the STAT3/TIMP3/MMP pathway and uncovered the molecular mechanism underlying its neuroprotective effect on mouse retinal photoreceptors.


Assuntos
Fármacos Neuroprotetores , Degeneração Retiniana , Animais , Camundongos , Apoptose , Fármacos Neuroprotetores/farmacologia , Células Fotorreceptoras , Degeneração Retiniana/induzido quimicamente , Degeneração Retiniana/genética , Fator de Transcrição STAT3/genética
11.
Naunyn Schmiedebergs Arch Pharmacol ; 397(3): 1421-1431, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37728622

RESUMO

Direct-acting antivirals (DAA) have become the treatment of choice for hepatitis C. Nevertheless, efficacy of DAA in preventing hepatitis C complications remains uncertain. We evaluated the impact of DAA on hepatocellular carcinoma (HCC) occurrence and recurrence, all-cause mortality, liver decompensation and liver transplantation as compared to non-DAA treated hepatitis C and the association to baseline liver status. A systematic search for articles from March 1993 to March 2022 was conducted using three electronic databases. Randomized, case-control and cohort studies with comparison to non-DAA treatment and reporting at least one outcome were included. Meta-analysis and sub-group meta-analysis based on baseline liver status were performed. Of 1497 articles retrieved, 19 studies were included, comprising of 266,310 patients (56.07% male). DAA reduced HCC occurrence significantly in non-cirrhosis (RR 0.80, 95% CI 0.69-0.92) and cirrhosis (RR 0.39, 95% CI 0.24-0.64) but not in decompensated cirrhosis. DAA treatment lowered HCC recurrence (RR 0.71, 95% CI 0.55-0.92) especially in patients with baseline HCC and waiting for liver transplant. DAA also reduced all-cause mortality (RR 0.43, 95% CI 0.23-0.78) and liver decompensation (RR 0.52, 95% CI 0.33-0.83) significantly. However, DAA did not prevent liver transplantation. The study highlighted the importance of early DAA initiation in hepatitis C treatment for benefits beyond sustained virological response. DAA therapy prevented HCC particularly in non-cirrhosis and compensated cirrhosis groups indicating benefits in preventing further worsening of liver status. Starting DAA early also reduced HCC recurrence, liver decompensation, and all-cause mortality.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Humanos , Masculino , Feminino , Carcinoma Hepatocelular/tratamento farmacológico , Antivirais/uso terapêutico , Neoplasias Hepáticas/tratamento farmacológico , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepacivirus , Cirrose Hepática/tratamento farmacológico
12.
ACS Nano ; 17(24): 25591-25613, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38078771

RESUMO

Spinal cord injury (SCI) causes tissue structure damage and composition changes of the neural parenchyma, resulting in severe consequences for spinal cord function. Mimicking the components and microstructure of spinal cord tissues holds promise for restoring the regenerative microenvironment after SCI. Here, we have utilized electrospinning technology to develop aligned decellularized spinal cord fibers (A-DSCF) without requiring synthetic polymers or organic solvents. A-DSCF preserves multiple types of spinal cord extracellular matrix proteins and forms a parallel-oriented structure. Compared to aligned collagen fibers (A-CF), A-DSCF exhibits stronger mechanical properties, improved enzymatic stability, and superior functionality in the adhesion, proliferation, axonal extension, and myelination of differentiated neural progenitor cells (NPCs). Notably, axon extension or myelination has been primarily linked to Agrin (AGRN), Laminin (LN), or Collagen type IV (COL IV) proteins in A-DSCF. When transplanted into rats with complete SCI, A-DSCF loaded with NPCs improves the survival, maturation, axon regeneration, and motor function of the SCI rats. These findings highlight the potential of structurally and compositionally biomimetic scaffolds to promote axonal extension and remyelination after SCI.


Assuntos
Remielinização , Traumatismos da Medula Espinal , Ratos , Animais , Axônios , Regeneração Nervosa , Medula Espinal , Traumatismos da Medula Espinal/terapia
13.
Conserv Biol ; : e14221, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37937455

RESUMO

Reliable maps of species distributions are fundamental for biodiversity research and conservation. The International Union for Conservation of Nature (IUCN) range maps are widely recognized as authoritative representations of species' geographic limits, yet they might not always align with actual occurrence data. In recent area of habitat (AOH) maps, areas that are not habitat have been removed from IUCN ranges to reduce commission errors, but their concordance with actual species occurrence also remains untested. We tested concordance between occurrences recorded in camera trap surveys and predicted occurrences from the IUCN and AOH maps for 510 medium- to large-bodied mammalian species in 80 camera trap sampling areas. Across all areas, cameras detected only 39% of species expected to occur based on IUCN ranges and AOH maps; 85% of the IUCN only mismatches occurred within 200 km of range edges. Only 4% of species occurrences were detected by cameras outside IUCN ranges. The probability of mismatches between cameras and the IUCN range was significantly higher for smaller-bodied mammals and habitat specialists in the Neotropics and Indomalaya and in areas with shorter canopy forests. Our findings suggest that range and AOH maps rarely underrepresent areas where species occur, but they may more often overrepresent ranges by including areas where a species may be absent, particularly at range edges. We suggest that combining range maps with data from ground-based biodiversity sensors, such as camera traps, provides a richer knowledge base for conservation mapping and planning.


Combinación de censos con fototrampas y mapas de extensión de la UICN para incrementar el conocimiento sobre la distribución de las especies Resumen Los mapas confiables de la distribución de las especies son fundamentales para la investigación y conservación de la biodiversidad. Los mapas de distribución de la Unión Internacional para la Conservación de la Naturaleza (UICN) están reconocidos como representaciones de autoridad de los límites geográficos de las especies, aunque no siempre se alinean con los datos actuales de su presencia. En los mapas recientes de área de hábitat (ADH), las áreas que no son hábitat han sido eliminadas de la distribución de la UICN para reducir los errores de comisión, pero su concordancia con la presencia actual de las especies tampoco ha sido analizada. Analizamos la concordancia entre la presencia registrada por los censos de fototrampas y pronosticamos la presencia a partir de los mapas de la UICN y de ADH de 510 especies de mamíferos de talla mediana a grande en 80 áreas de muestreo de fototrampas. Las cámaras detectaron sólo el 39% de las especies esperadas con base en la distribución de la UICN y los mapas de ADH en todas las áreas; el 85% de las disparidades con la UICN ocurrieron dentro de los 200 km a partir del borde de la distribución. Sólo el 4% de la presencia de las especies fue detectada por las cámaras ubicadas fuera de la distribución de la UICN. La probabilidad de disparidad entre las cámaras y la UICN fue significativamente mayor para los mamíferos de talla pequeña y para los especialistas de hábitat en las regiones Neotropical e Indomalaya y en áreas con doseles forestales más bajos. Nuestros hallazgos sugieren que los mapas de distribución y ADH pocas veces subrepresentan las áreas con presencia de las especies, pero con frecuencia pueden sobrerrepresentar la distribución al incluir áreas en donde las especies pueden estar ausentes, en particular los bordes de la distribución. Sugerimos que la combinación de los mapas de distribución con los sensores de biodiversidad en tierra, como las fototrampas, proporciona una base más rica de conocimiento para el mapeo y la planeación de la conservación.

14.
Pulm Circ ; 13(3): e12291, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37744669

RESUMO

Right heart thrombus (RHT) is a rare but life-threatening condition in acute pulmonary embolism (APE) without clear management guidelines. This study aimed to address the clinical characteristics and outcomes of RHT-APE in Chinese patients. In this study, 17 RHT-APE and 329 non-RHT-APE patients, who were diagnosed between September 2015 and August 2019, were retrospectively recruited with the median follow-up was 360 days. The overall prevalence of RHT was 4.91% in APE. Its prevalence increased along the increase of APE risk stratifications. Comparisons showed that with higher proportion of male gender and younger age, RHT-APE patients also had worse hemodynamic instability and heart function, and higher risk stratification levels than non-RHT-APE patients. After adjusting by age and gender, multivariate logistic regression analysis found high/intermediate-high risk stratification, decreased right ventricular (RV) motion, NT-proBNP >600 pg/mL, and RV dysfunction were risk factors for RHT. Kaplan-Meier analysis showed non-RHT had better prognosis than RHT patients (30-day survival: log-rank: p < 0.001; 90-day survival: log-rank: p = 0.002). The multivariate logistic regression analysis showed RHT was an independent risk factor for 30-day mortality in APE. The subgroup analysis showed RHT would result in worse outcomes in patients who already had higher APE early mortality risk. RHT would increase the risk of 30- and 90-day mortality in APE. More attention should be paid to young male APE patients with decreased RV motion, NT-proBNP >600 pg/mL, RV dysfunction, or high level of risk stratification, to exclude the coexistence of RHT.

15.
Front Microbiol ; 14: 1206603, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37448575

RESUMO

Introduction: The chestnut blight fungus, Cryphonectria parasitica, and hypovirus have been used as a model to probe the mechanism of virulence and regulation of traits important to the host fungus. Previous studies have indicated that mitochondria could be the primary target of the hypovirus. Methods: In this study, we report a comprehensive and comparative study comprising mitochondrion quantification, reactive oxygen species (ROS) and respiratory efficiency, and quantitative mitochondrial proteomics of the wild-type and virus-infected strains of the chestnut blight fungus. Results and discussion: Our data show that hypovirus infection increases the total number of mitochondria, lowers the general ROS level, and increases mitochondrial respiratory efficiency. Quantification of mitochondrial proteomes revealed that a set of proteins functioning in energy metabolism and mitochondrial morphogenesis, as well as virulence, were regulated by the virus. In addition, two viral proteins, p29 and p48, were found to co-fractionate with the mitochondrial membrane and matrix. These results suggest that hypovirus perturbs the host mitochondrial functions to result in hypovirulence.

17.
Angew Chem Int Ed Engl ; 62(18): e202217954, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-36869401

RESUMO

An unprecedent asymmetric catalytic benzilic amide rearrangement for the synthesis of α,α-disubstituted piperazinones is reported. The reaction proceeds via a domino [4+1] imidazolidination/formal 1,2-nitrogen shift/1,2-aryl or alkyl migration sequence, employing readily available vicinal tricarbonyl compounds and 1,2-diamines as starting materials. This approach provides an efficient access to chiral C3-disubsituted piperazin-2-ones with high enantiocontrol, which are exceedingly difficult to access from the existing synthetic methodologies. The observed enantioselectivity was proposed to be controlled by dynamic kinetic resolution in the 1,2-aryl/alkyl migration step. The resulting densely functionalized products are versatile building blocks to bioactive natural products, drug molecules and their analogues.

18.
Sci Adv ; 9(6): eade8829, 2023 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-36753555

RESUMO

Noncovalent interactions between cells and environmental cues have been recognized as fundamental physiological interactions that regulate cell behavior. However, the effects of the covalent interactions between cells and biomaterials on cell behavior have not been examined. Here, we demonstrate a combined strategy based on covalent conjugation between biomaterials (collagen fibers/lipid nanoparticles) and various cells (exogenous neural progenitor cells/astrocytes/endogenous tissue-resident cells) to promote neural regeneration after spinal cord injury (SCI). We found that metabolic azido-labeled human neural progenitor cells conjugated on dibenzocyclooctyne-modified collagen fibers significantly promoted cell adhesion, spreading, and differentiation compared with noncovalent adhesion. In addition, dibenzocyclooctyne-modified lipid nanoparticles containing edaravone, a well-known ROS scavenger, could target azide-labeled spinal cord tissues or transplanted azide-modified astrocytes to improve the SCI microenvironment. The combined application of these covalent conjugation strategies in a rat SCI model boosted neural regeneration, suggesting that the covalent interactions between cells and biomaterials have great potential for tissue regeneration.


Assuntos
Materiais Biocompatíveis , Traumatismos da Medula Espinal , Ratos , Animais , Humanos , Materiais Biocompatíveis/farmacologia , Engenharia Tecidual , Tecidos Suporte , Azidas , Medula Espinal , Traumatismos da Medula Espinal/terapia , Colágeno
19.
Front Cell Infect Microbiol ; 12: 1035364, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36339346

RESUMO

Vibrio parahaemolyticus is a common pathogen usually controlled by antibiotics in mariculture. Notably, traditional antibiotic therapy is becoming less effective because of the emergence of bacterial resistance, hence new strategies need to be found to overcome this challenge. Bacteriophages, a class of viruses that lyse bacteria, can help us control drug-resistant bacteria. In this study, a novel Vibrio parahaemolyticus phage phiTY18 isolated from the coastal water of Xiamen was explored. Transmission electron microscopy showed that phiTY18 had an icosahedral head of 130.0 ± 1.2 nm diameter and a contractile tail of length of 66.7 ± 0.6 nm. The phage titer could reach 7.2×1010 PFU/mL at the optimal MOI (0.01). The phage phiTY18 had a degree of tolerance to heat and acid and base. At the temperature of 50°C (pH7.0, 1h) the survival phages reached 1.28×106 PFU/mL, and at pH 5-9 (30°C, 1h), the survival phages was greater than 6.37×107 PFU/mL Analysis of the phage one-step growth curve revealed that it had a latent period of 10min, a rise period of 10min, and an average burst size of the phage was 48 PFU/cell. Genome sequencing and analysis drew that phage phiTY18 had double-stranded DNA (191,500 bp) with 34.90% G+C content and contained 117 open reading frames (ORFs) and 24 tRNAs. Phylogenetic tree based on major capsid protein (MCP) revealed that phage phiTY18 (MW451250) was highly related to two Vibrio phages phiKT1024 (OM249648) and Va1 (MK387337). The NCBI alignment results showed that the nucleotide sequence identity was 97% and 93%, respectively. In addition, proteomic tree analysis indicated that phage phiTY18, phiKT1024, and Va1 were belong to the same virus sub-cluster within Myoviridae. This study provides a theoretical basis for understanding the genomic characteristics and the interaction between Vibrio parahaemolyticus phages and their host.


Assuntos
Bacteriófagos , Vibrio parahaemolyticus , Bacteriófagos/genética , Vibrio parahaemolyticus/genética , Filogenia , Proteômica , Genoma Viral , Genômica , Fases de Leitura Aberta , Água
20.
ESC Heart Fail ; 9(5): 3407-3417, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35841124

RESUMO

AIMS: Orchestrating the transition from reversible medial hypertrophy to irreversible plexiform lesions is crucial for pulmonary arterial hypertension related to congenital heart disease (CHD-PAH). Transgelin is an actin-binding protein that modulates pulmonary arterial smooth muscle cell (PASMC) dysfunction. In this study, we aimed to probe the molecular mechanism and biological function of transgelin in the pathogenesis of CHD-PAH. METHODS AND RESULTS: Transgelin expression was detected in lung tissues from both CHD-PAH patients and monocrotaline (MCT)-plus aortocaval (AV)-induced PAH rats by immunohistochemistry. In vitro, the effects of transgelin on the proliferation, migration, and apoptosis of human PASMCs (HPASMCs) were evaluated by the cell count and EdU assays, transwell migration assay, and TUNEL assay, respectively. And the effect of transgelin on the expression of HPASMC phenotype markers was assessed by the immunoblotting assay. (i) Compared with the normal control group (n = 12), transgelin expression was significantly overexpressed in the pulmonary arterioles of the reversible (n = 15) and irreversible CHD-PAH group (n = 4) (reversible group vs. control group: 18.2 ± 5.1 vs. 13.6 ± 2.6%, P < 0.05; irreversible group vs. control group: 29.9 ± 4.7 vs. 13.6 ± 2.6%, P < 0.001; irreversible group vs. reversible group: 29.9 ± 4.7 vs. 18.2 ± 5.1, P < 0.001). This result was further confirmed in MCT-AV-induced PAH rats. Besides, the transgelin expression level was positively correlated with the pathological grading of pulmonary arteries in CHD-PAH patients (r = 0.48, P = 0.03, n = 19). (ii) Compared with the normal control group (n = 12), TGF-ß1 expression was notably overexpressed in the pulmonary arterioles of the reversible (n = 15) and irreversible CHD-PAH group (n = 4) (reversible group vs. control group: 14.8 ± 4.4 vs. 6.0 ± 2.5%, P < 0.001; irreversible group vs. control group: 20.1 ± 4.4 vs. 6.0 ± 2.5%, P < 0.001; irreversible group vs. reversible group: 20.1 ± 4.4 vs. 14.8 ± 4.4, P < 0.01). The progression-dependent correlation between TGF-ß1 and transgelin was demonstrated in CHD-PAH patients (r = 0.48, P = 0.04, n = 19) and MCT-AV-induced PAH rats, which was further confirmed at sub-cellular levels. (iii) Knockdown of transgelin diminished proliferation, migration, apoptosis resistance, and phenotypic transformation of HPASMCs through repressing the TGF-ß1 signalling pathway. On the contrary, transgelin overexpression resulted in the opposite effects. CONCLUSIONS: These results indicate that transgelin may be an indicator of CHD-PAH development via boosting HPASMC dysfunction through positive regulation of the TGF-ß1 signalling pathway, as well as a potential therapeutic target for the treatment of CHD-PAH.


Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Animais , Humanos , Ratos , Proliferação de Células/genética , Hipertensão Pulmonar/etiologia , Proteínas dos Microfilamentos/metabolismo , Monocrotalina/metabolismo , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , Hipertensão Arterial Pulmonar/etiologia , Artéria Pulmonar , Fator de Crescimento Transformador beta1/metabolismo
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