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1.
FASEB J ; 37(5): e22905, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37039817

RESUMO

The hepatic vascular niche plays an important role in the pathological process of liver fibrosis. Liver sinusoidal endothelial cells (LSECs) predominantly compose hepatic vascular niches. Endothelial cell (EC)-expressing sphingosine 1-phosphate receptor 2 (S1pr2) plays an essential role in the regulation of vascular functions. Nevertheless, it remains unknown whether liver LSEC-S1pr2 might modulate pathological liver fibrosis. In this study, liver fibrosis was induced by hepatotoxin carbon tetrachloride (CCl4 ). The expression of S1pr2 is significantly downregulated in liver sinusoidal endothelial cells after CCl4 treatment. The loss of S1pr2 in LSECs significantly alleviated liver fibrosis after chronic insult, whereas the overexpression of S1pr2 in LSECs accentuated liver fibrogenesis. In vivo experiments further revealed that the deficiency of S1pr2 in LSECs dampened hepatic stellate cell (HSC) activation, while overexpression of S1pr2 in LSECs enhanced HSC activation with more extracellular matrix component production. Mechanistically, LSEC-S1pr2 activates the YAP signaling pathway to potentiate the transactivation of TGF-ß, which acts on HSCs in a paracrine manner, and thus aggravated liver fibrosis. Taken together, our results uncover a novel pathological mechanism of liver fibrosis in which LSEC-S1pr2 plays an important role in modulating the development of liver fibrosis, providing a future novel therapy target against liver fibrogenesis.


Assuntos
Células Endoteliais , Cirrose Hepática , Humanos , Células Endoteliais/metabolismo , Receptores de Esfingosina-1-Fosfato/metabolismo , Cirrose Hepática/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
2.
J Appl Toxicol ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760888

RESUMO

Multidrug and toxin extrusion protein 1 (MATE1), an efflux transporter mainly expressed in renal proximal tubules, mediates the renal secretion of organic cationic drugs. The inhibition of MATE1 will impair the excretion of drugs into the tubular lumen, leading to the accumulation of nephrotoxic drugs in the kidney and consequently potentiating nephrotoxicity. Screening and identifying potent MATE1 inhibitors can predict or minimize the risk of drug-induced kidney injury. Flavonoids, a group of polyphenols commonly found in foodstuffs and herbal products, have been reported to cause transporter-mediated food/herb-drug interactions. Our objective was to investigate the inhibitory effects of flavonoids on MATE1 in vitro and in vivo and to assess the effects of flavonoids on cisplatin-induced kidney injury. Thirteen flavonoids exhibited significant transport activity inhibition (>50%) on MATE1 in MATE1-MDCK cells. Among them, the six strongest flavonoid inhibitors, including irisflorentin, silymarin, isosilybin, sinensetin, tangeretin, and nobiletin, markedly increased cisplatin cytotoxicity in these cells. In cisplatin-induced in vivo renal injury models, irisflorentin, isosilybin, and sinensetin also increased serum creatinine and blood urea nitrogen levels to different degrees, especially irisflorentin, which exhibited the most potent nephrotoxicity with cisplatin. The pharmacophore model indicated that the hydrogen bond acceptors at the 3, 5, and 7 positions may play a critical role in the inhibitory effect of flavonoids on MATE1. Our findings provide helpful information for predicting the potential risks of flavonoid-containing food/herb-drug interactions and avoiding the exacerbation of drug-induced kidney injury via MATE1 mediation.

3.
Proc Natl Acad Sci U S A ; 118(24)2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34108238

RESUMO

Galanin receptor1 (GalR1) transcript levels are elevated in the rat ventral periaqueductal gray (vPAG) after chronic mild stress (CMS) and are related to depression-like behavior. To explore the mechanisms underlying the elevated GalR1 expression, we carried out molecular biological experiments in vitro and in animal behavioral experiments in vivo. It was found that a restricted upstream region of the GalR1 gene, from -250 to -220, harbors an E-box and plays a negative role in the GalR1 promoter activity. The transcription factor Scratch2 bound to the E-box to down-regulate GalR1 promoter activity and lower expression levels of the GalR1 gene. The expression of Scratch2 was significantly decreased in the vPAG of CMS rats. Importantly, local knockdown of Scratch2 in the vPAG caused elevated expression of GalR1 in the same region, as well as depression-like behaviors. RNAscope analysis revealed that GalR1 mRNA is expressed together with Scratch2 in both GABA and glutamate neurons. Taking these data together, our study further supports the involvement of GalR1 in mood control and suggests a role for Scratch2 as a regulator of depression-like behavior by repressing the GalR1 gene in the vPAG.


Assuntos
Comportamento Animal , Depressão/patologia , Substância Cinzenta Periaquedutal/patologia , Receptor Tipo 1 de Galanina/metabolismo , Fatores de Transcrição/metabolismo , Animais , Elementos E-Box/genética , Neurônios GABAérgicos/metabolismo , Regulação da Expressão Gênica , Ácido Glutâmico/metabolismo , Células PC12 , Regiões Promotoras Genéticas/genética , Ligação Proteica , Ratos , Receptor Tipo 1 de Galanina/genética , Estresse Psicológico/complicações , Fatores de Transcrição/genética , Sítio de Iniciação de Transcrição
4.
Appl Environ Microbiol ; 88(7): e0006022, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35285711

RESUMO

Bacterial porin-encoding genes are often found under positive selection. Local recombination has also been identified in a few of them to facilitate bacterial rapid adaptation, although it remains unknown whether it is a common evolutionary mechanism for the porins or outer membrane proteins in Gram-negative bacteria. In this study, we investigated the beta-barrel (ß-barrel) porin-encoding genes in Escherichia coli that were reported under positive Darwinian selection. Besides fhuA that was found with ingenic local recombination previously, we identified four other genes, i.e., lamB, ompA, ompC, and ompF, all showing the similar mosaic evolution patterns. Comparative analysis of the protein sequences disclosed a list of highly variable regions in each family, which are mostly located in the convex of extracellular loops and coinciding with the binding sites of bacteriophages. For each of the porin families, mosaic recombination leads to unique combinations of the variable regions with different sequence patterns, generating diverse protein groups. Structural modeling indicated a conserved global topology among the different porins, with the extracellular surface varying a lot due to individual or combinatorial variable regions. The conservation of global tertiary structure would ensure the channel activity, while the wide diversity of variable regions may represent selection to avoid the invasion of phages, antibiotics or immune surveillance factors. Our study identified multiple bacterial porin genes with mosaic evolution. We hypothesize that this could be generalized strategy for outer membrane proteins to both maintain normal life processes and evade the attack of unfavored factors rapidly. IMPORTANCE Microevolution studies can disclose more elaborate evolutionary mechanisms of genes, appearing especially important for genes with multifaceted function such as those encoding outer membrane proteins. However, in most cases, the gene is considered as a whole unit, and the evolutionary patterns are disclosed. Here, we report that multiple bacterial porin proteins follow mosaic evolution, with local ingenic recombination combined with spontaneous mutations based on positive Darwinian selection, and conservation for most structural regions. This could represent a common mechanism for bacterial outer membrane proteins. The variable regions within each porin family showed large coincidence with the binding sites of bacteriophages, antibiotics, and immune factors and therefore would represent effective targets for the development of new antibacterial agents or vaccines.


Assuntos
Escherichia coli , Porinas , Animais , Antibacterianos/metabolismo , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Bactérias/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Humanos , Porinas/genética , Porinas/metabolismo , Ovinos
5.
J Biol Chem ; 295(33): 11669-11681, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32571873

RESUMO

Despite years of research investigating osteoblast differentiation, the mechanisms by which transcription factors regulate osteoblast maturation, bone formation, and bone homeostasis is still unclear. It has been reported that runt-related transcription factor 1 (Runx1) is expressed in osteoblast progenitors, pre-osteoblasts, and mature osteoblasts; yet, surprisingly, the exact function of RUNX1 in osteoblast maturation and bone formation remains unknown. Here, we generated and characterized a pre-osteoblast and differentiating chondrocyte-specific Runx1 conditional knockout mouse model to study RUNX1's function in bone formation. Runx1 ablation in osteoblast precursors and differentiating chondrocytes via osterix-Cre (Osx-Cre) resulted in an osteoporotic phenotype and decreased bone density in the long bones and skulls of Runx1f/fOsx-Cre mice compared with Runx1f/f and Osx-Cre mice. RUNX1 deficiency reduced the expression of SRY-box transcription factor 9 (SOX9), Indian hedgehog signaling molecule (IHH), Patched (PTC), and cyclin D1 in the growth plate, and also reduced the expression of osteocalcin (OCN), OSX, activating transcription factor 4 (ATF4), and RUNX2 in osteoblasts. ChIP assays and promoter activity mapping revealed that RUNX1 directly associates with the Runx2 gene promoter and up-regulates Runx2 expression. Furthermore, the ChIP data also showed that RUNX1 associates with the Ocn promoter. In conclusion, RUNX1 up-regulates the expression of Runx2 and multiple bone-specific genes, and plays an indispensable role in bone formation and homeostasis in both trabecular and cortical bone. We propose that stimulating Runx1 activity may be useful in therapeutic approaches for managing some bone diseases such as osteoporosis.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Osteoblastos/citologia , Osteogênese , Animais , Diferenciação Celular , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Feminino , Masculino , Camundongos , Camundongos Knockout , Osteoblastos/metabolismo , Osteoporose/genética , Osteoporose/metabolismo
6.
Eur J Pediatr ; 180(3): 929-936, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33011830

RESUMO

The aim of this retrospective study was to investigate the clinical characteristics and therapeutic outcomes of pulmonary arterial hypertension (PAH) secondary to congenital portosystemic shunts (CPSS). Thirty-three pediatric patients diagnosed in our institution with CPSS between 2012 and 2019 were enrolled in this study. The patients were divided into PAH and non-PAH groups. The PAH group included 15 patients who presented with unexplained PAH when CPSS was diagnosed. Two patients with microangiopathic hemolytic anemia died of right heart failure shortly after diagnosis. One patient received a liver transplant at the age of 4.3 years and showed a mild decrease in pulmonary artery pressure (PAP) 4 years after the operation. Seven patients underwent one-stage shunt closure at a median age of 2.8 years (1.4-13 years). Follow-up examinations, from 1.6 to 4.1 years after intervention, showed marked reduction of PAP in one patient and stabilization of PAH in six others. However, in one patient who underwent two-stage shunt closure, a marked increase in PAP was noted after partial ligation of the shunt. The remaining four patients received only pulmonary vasodilator therapy, and one of them died of right heart failure 12 years after the PAH diagnosis. The non-PAH group included 18 patients without evidence of PAH upon CPSS diagnosis. Shunt closure was carried out in eight of these patients, but one patient subsequently developed PAH after the resolution of hepatopulmonary syndrome.Conclusion: CPSS may be a more likely cause of unexplained PAH in pediatric patients than previously thought. Shunt closure or liver transplantation may prevent the progression of PAH, or even improve it for the majority of CPSS patients.


Assuntos
Derivação Portossistêmica Transjugular Intra-Hepática , Hipertensão Arterial Pulmonar , Malformações Vasculares , Criança , Pré-Escolar , Humanos , Estudos Retrospectivos , Resultado do Tratamento
7.
Biochem J ; 477(13): 2421-2438, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32391876

RESUMO

One of the fundamental questions in bone biology is where osteoblasts originate and how osteoblast differentiation is regulated. The mechanism underlying which factors regulate chondrocyte to osteoblast lineage commitment remains unknown. Our data showed that Runt-related transcription factor 1 (Runx1) is expressed at different stages of both chondrocyte and osteoblast differentiation. Runx1 chondrocyte-specific knockout (Runx1f/fCol2α1-cre) mice exhibited impaired cartilage formation, decreased bone density, and an osteoporotic phenotype. The expressions of chondrocyte differentiation regulation genes, including Sox9, Ihh, CyclinD1, PTH1R, and hypertrophic chondrocyte marker genes including Col2α1, Runx2, MMP13, Col10α1 in the growth plate were significantly decreased in Runx1f/fCol2α1-cre mice chondrocytes. Importantly, the expression of osteoblast differentiation regulation genes including Osx, Runx2, ATF4, and osteoblast marker genes including osteocalcin (OCN) and osteopontin (OPN) were significantly decreased in the osteoblasts of Runx1f/fCol2α1-cre mice. Notably, our data showed that osteoblast differentiation regulation genes and marker genes are also expressed in chondrocytes and the expressions of these marker genes were significantly decreased in the chondrocytes of Runx1f/fCol2α1-cre mice. Our data showed that chromatin immunoprecipitation (ChIP) and promoter mapping analysis revealed that Runx1 directly binds to the Indian hedgehog homolog (Ihh) promoter to regulate its expression, indicating that Runx1 directly regulates the transcriptional expression of chondrocyte genes. Collectively, we revealed that Runx1 signals chondrocyte to osteoblast lineage commitment and promotes endochondral bone formation through enhancing both chondrogenesis and osteogenesis genes expressions, indicating Runx1 may be a therapeutic target to enhance endochondral bone formation and prevent osteoporosis fractures.


Assuntos
Condrócitos/citologia , Condrócitos/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Adipogenia/genética , Adipogenia/fisiologia , Animais , Western Blotting , Células Cultivadas , Condrogênese/genética , Condrogênese/fisiologia , Imunoprecipitação da Cromatina , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Imunofluorescência , Imuno-Histoquímica , Camundongos , Osteogênese/genética , Osteogênese/fisiologia , Reação em Cadeia da Polimerase em Tempo Real
8.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(2): 112-116, 2021 Feb 10.
Artigo em Zh | MEDLINE | ID: mdl-33565060

RESUMO

OBJECTIVE: To explore the genetic basis for 7 patients with Alström syndrome. METHODS: DNA was extracted from peripheral blood samples of the patients and their parents. Whole exome sequencing was carried out for the patients. Suspected variant was verified by Sanger sequencing and bioinformatic analysis. RESULTS: Genetic testing revealed 12 variants of the ALMS1 gene among the 7 patients, including 7 nonsense and 5 frameshift variants, which included c.5418delC (p.Tyr1807Thrfs*23), c.10549C>T (p.Gln3517*), c.9145dupC (p.Thr3049Asnfs*12), c.10819C>T (p.Arg3607*), c.5701_5704delGAGA (p.Glu1901Argfs*18), c.9154_9155delCT (p.Cys3053Serfs*9), c.9460delG (p.Val3154*), c.9379C>T (p.Gln3127*), c.12115C>T (p.Gln4039*), c.1468dupA (p.Thr490Asnfs*15), c.10825C>T (p.Arg3609*) and c.3902C>A (p.Ser1301*). Among these, c.9154_ 9155delCT, c.9460delG, c.9379C>T, and c.1468dupA were unreported previously. Based on the standards and guidelines of American College of Medical Genetics and Genomics, the c.9379C>T and c.12115C>T variants of the ALMS1 gene were predicted to be likely pathogenic (PVS1+PM2), whilst the other 10 variants were predicted to be pathogenic (PVS1+ PM2+ PP3+PP4). CONCLUSION: ALMS1 variants probably underlay the Alström syndrome in the 7 patients, and genetic testing can provide a basis for the clinical diagnosis of this syndrome. The discovery of four novel variants has expanded the mutational spectrum of Alström syndrome.


Assuntos
Síndrome de Alstrom , Proteínas de Ciclo Celular/genética , Síndrome de Alstrom/genética , Humanos , Mutação , Linhagem , Sequenciamento do Exoma
9.
J Cell Mol Med ; 24(2): 2013-2026, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31854513

RESUMO

Cardiac vascular microenvironment is crucial for cardiac remodelling during the process of heart failure. Sphingosine 1-phosphate (S1P) tightly regulates vascular homeostasis via its receptor, S1pr1. We therefore hypothesize that endothelial S1pr1 might be involved in pathological cardiac remodelling. In this study, heart failure was induced by transverse aortic constriction (TAC) operation. S1pr1 expression is significantly increased in microvascular endothelial cells (ECs) of post-TAC hearts. Endothelial-specific deletion of S1pr1 significantly aggravated cardiac dysfunction and deteriorated cardiac hypertrophy and fibrosis in myocardium. In vitro experiments demonstrated that S1P/S1pr1 praxis activated AKT/eNOS signalling pathway, leading to more production of nitric oxide (NO), which is an essential cardiac protective factor. Inhibition of AKT/eNOS pathway reversed the inhibitory effect of EC-S1pr1-overexpression on angiotensin II (AngII)-induced cardiomyocyte (CM) hypertrophy, as well as on TGF-ß-mediated cardiac fibroblast proliferation and transformation towards myofibroblasts. Finally, pharmacological activation of S1pr1 ameliorated TAC-induced cardiac hypertrophy and fibrosis, leading to an improvement in cardiac function. Together, our results suggest that EC-S1pr1 might prevent the development of pressure overload-induced heart failure via AKT/eNOS pathway, and thus pharmacological activation of S1pr1 or EC-targeting S1pr1-AKT-eNOS pathway could provide a future novel therapy to improve cardiac function during heart failure development.


Assuntos
Células Endoteliais/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Pressão , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Receptores de Esfingosina-1-Fosfato/metabolismo , Remodelação Ventricular , Animais , Aorta/patologia , Aorta/fisiopatologia , Apoptose , Capilares/patologia , Cardiomegalia/complicações , Cardiomegalia/patologia , Cardiomegalia/fisiopatologia , Movimento Celular , Proliferação de Células , Constrição Patológica , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Camundongos Knockout , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Tamanho do Órgão , Ratos , Receptores de Esfingosina-1-Fosfato/genética , Regulação para Cima/genética
10.
Pacing Clin Electrophysiol ; 43(1): 37-46, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31701534

RESUMO

BACKGROUND: Ventricular tachycardia (VT) with or without structural heart disease is uncommon but well-recognized clinically in children. With this retrospective study, we collected the data from the in-hospital pediatric patients of VT with catheter ablation therapy. The purpose of this study is to assess the acute results and the long-term outcome of catheter ablation in pediatric patients of VT in our single pediatric center. METHODS: This study included 53 consecutive children (male/female = 33/20, mean age = 8.2 ± 3.4 years, mean bodyweight = 32.6 ± 13.7 kg). All patients underwent electrophysiological study with an attempt of catheter ablation for clinical monomorphic VT. Acute and long-term success rate of catheter ablation for the treatment of VT were compared between right and left VT as well as fascicular VT (FVT) and nonfascicular VT. RESULTS: There were 53 idiopathic VT forms found in the children, including FVT (n = 32), outflow tract VT (n = 15), papillary muscle VT (n = 5), and bundle branch reentry VT (n = 1). Acute success of catheter ablations for VT was achieved in 57 of all the 59 ablation procedures (97%) with VT recurrence occurred in six of 53 patients (11%). During a mean follow-up period of 29.2 ± 21.7 months (range 1-76 months) after hospital discharge, ablations in nonfascicular VT were as successful as FVT. There was no significant difference in the success rate between the right and left VT. CONCLUSION: Catheter ablation is an effective treatment for idiopathic VT in children. The acute and long-term success rates of catheter ablation for idiopathic VT in pediatric patients with normal heart structure are satisfying.


Assuntos
Ablação por Cateter/métodos , Taquicardia Ventricular/cirurgia , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos , Taquicardia Ventricular/fisiopatologia
11.
Heart Vessels ; 35(5): 731-741, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31912231

RESUMO

Atrial arrhythmia is an important cause of late death in patients after the Fontan-Style operation. However, the detailed electrophysiological characteristics of the post-Fontan atrium and its underlying mechanisms are largely unknown. In this study, we investigated electrophysiological characteristics and the ionic remodeling in the right atrium (RA) of a canine model after the Fontan operation. We performed the operation of RA to pulmonary artery connection to mimic the Fontan operation. We undertook hemodynamic measurements, cardiac electrophysiological studies, and ion current measurements. The expression of ionic channels was analyzed by PCR and western-blotting. Our Fontan model induced RA hypertension, enlarged the size of RA, and increased atrial fibrosis, representing the classic characteristic of Fontan patients. In the Fontan group, the atrial effective refractory period and the active potential duration were reduced, and the atrial tachycardia has been more often to be induced. The electrical conduction mapping showed that the Fontan group reduced the conduction velocity. The Fontan operation significantly down-regulated the expression of KCND3/Kv4.3, CACNA1C/Cav1.2 and SCN5A, but up-regulated the expression of KCNJ2/Kir2.1. Correspondingly, The Fontan operation reduced transient-outward (Ito) and L-type Ca2 (ICa,L) and INa currents, while increasing the inward-rectifier current (IK1). Thus, the net shortening of the action potential in the post-Fontan atrium is associated with the altered expression of ionic channels which disturbed the balance between inward and outward currents. Taken together, the Fontan operation induces the ionic remodeling, and thus altered electrophysiological characteristics of the right atrium, improving our understanding on the pathophysiology of atrial arrhythmias in Fontan patients.


Assuntos
Arritmias Cardíacas/etiologia , Remodelamento Atrial , Técnica de Fontan/efeitos adversos , Átrios do Coração/metabolismo , Canais Iônicos/metabolismo , Potenciais de Ação , Animais , Arritmias Cardíacas/metabolismo , Arritmias Cardíacas/fisiopatologia , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Modelos Animais de Doenças , Cães , Fibrose , Átrios do Coração/fisiopatologia , Frequência Cardíaca , Canais Iônicos/genética , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Shal/genética , Canais de Potássio Shal/metabolismo , Transdução de Sinais
12.
Curr Genet ; 65(4): 981-994, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30852625

RESUMO

The target of rapamycin (TOR) signaling pathway plays critical roles in regulating vegetative development and virulence in Fusarium graminearum. Previously, we have demonstrated that the putative type 2A phosphatase FgPpg1, a downstream component of the pathway, is important for hyphal growth, sporulation, DON biosynthesis and virulence. Here, we report the identification of FgHLTF1 putatively encoding a histone-like transcription factor by the transcriptome analysis of an ΔFgppg1 mutant. The FgHLTF1 expression was significantly down-regulated by the deletion of FgPPG1 or treatment with rapamycin. Analysis of an F. graminearum strain expressing green fluorescent protein (GFP) revealed that FgHltf1-GFP fusion protein mainly localized to the nucleus. Targeted gene deletion mutants of FgHLTF1 exhibited a significant reduction in vegetative growth, sexual reproduction and virulence. Moreover, the growth of the ΔFghltf1 mutants was restricted by hyperosmotic stresses. Unlike the wild-type strain, the mutants showed anomalous subcellular translocation of FgHog1-GFP under hyperosmotic conditions, suggesting that FgHLTF1 is associated with the high osmolarity glycerol response pathway. Taken together, we conclude that FgHLTF1 is transcriptionally regulated by the TOR signaling pathway and plays important roles in regulating vegetative growth, sexual reproduction, virulence and hyperosmotic stresses in F. graminearum.


Assuntos
Fusarium/genética , Histonas/genética , Reprodução/genética , Fatores de Transcrição/genética , Parede Celular/genética , Fusarium/patogenicidade , Regulação Fúngica da Expressão Gênica , Hifas/genética , Hifas/crescimento & desenvolvimento , Proteínas Mutantes/genética , Pressão Osmótica/fisiologia , Transdução de Sinais/genética , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Serina-Treonina Quinases TOR/genética , Transcriptoma/genética , Virulência/genética
13.
Small ; 15(1): e1804332, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30488562

RESUMO

Nanotechnology employs multifunctional engineered materials in the nanoscale range that provides many opportunities for translational stem cell research and therapy. Here, a cell-penetrating peptide (virus-1 transactivator of transcription)-conjugated, porous silicon nanoparticle (TPSi NP) loaded with the Wnt3a protein to increase both the cell survival rate and the delivery precision of stem cell transplantation via a combinational theranostic strategy is presented. The TPSi NP with a pore size of 10.7 nm and inorganic framework enables high-efficiency loading of Wnt3a, prolongs Wnt3a release, and increases antioxidative stress activity in the labeled mesenchymal stem cells (MSCs), which are highly beneficial properties for cell protection in stem cell therapy for myocardial infarction. It is confirmed that the intracellular aggregation of TPSi NPs can highly amplify the acoustic scattering of the labeled MSCs, resulting in a 2.3-fold increase in the ultrasound (US) signal compared with that of unlabeled MSCs. The translational potential of the designed nanoagent for real-time US imaging-guided stem cell transplantation is confirmed via intramyocardial injection of labeled MSCs in a nude mouse model. It is proposed that the intracellular aggregation of protein drug-loaded TPSi NPs could be a simple but robust strategy for improving the therapeutic effect of stem cell therapy.


Assuntos
Citoproteção , Endocitose , Imageamento Tridimensional , Células-Tronco Mesenquimais/citologia , Nanopartículas/química , Silício/química , Ultrassom , Proteínas Virais/metabolismo , Animais , Antioxidantes/farmacologia , Diferenciação Celular , Sobrevivência Celular , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Camundongos Nus , Miocárdio/metabolismo , Nanopartículas/ultraestrutura , Porosidade , Proteína Wnt3A/metabolismo
14.
Cell Tissue Res ; 375(3): 723-731, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30392145

RESUMO

Cultured skin has been used extensively for testing therapeutic drugs because it replicates the physical and biochemical properties of whole skin. However, traditional static culture cannot fully maintain cell viability and skin morphology because of the limitations involved with nutrient transmission. Here, we develop a new dynamic perfusion platform for skin culture and compare it with a static culture device. Rat skins were cultured in either static or dynamic condition for 0, 3, 6, 9 and 12 days. H&E, periodic acid-Schiff (PAS) and picrosirius red (PSR) staining were used for skin morphology detection, immunostaining against cytokeratin 10 (CK10) for differentiation detection, immunostaining against proliferating cell nuclear antigen (PCNA) for cell proliferation detection and TUNEL staining for apoptosis detection. After culturing for 12 days, the epidermis, basement membrane, hair follicles and connective tissue were disrupted in the static group, whereas these features were preserved in the dynamic group. Moreover, compared to the static group, proliferation in the epidermis and hair follicles was significantly improved and apoptosis in dermis was significantly decreased in the dynamic group. These findings suggest that our device is effective for extending the culture period of rat skin to maintain its characteristics and viability in vitro.


Assuntos
Pele/crescimento & desenvolvimento , Técnicas de Cultura de Tecidos/instrumentação , Técnicas de Cultura de Tecidos/métodos , Animais , Apoptose , Proliferação de Células , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos Sprague-Dawley , Pele/anatomia & histologia , Pele/citologia , Coloração e Rotulagem
16.
Implant Dent ; 28(6): 564-570, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31517651

RESUMO

PURPOSE: The aim of this study is to investigate the biological activity and antibacterial property of cerium oxide-incorporated calcium silicate coatings (CeO2-CS) in dental implants. MATERIALS AND METHODS: In this study, MC3T3-E1 cells cultured on the plastic, Ti-6Al-4V, and the cerium oxide-incorporated calcium silicate coatings (CeO2-CS) coating served as the blank, control, and CeO2-CS groups, respectively. A cell counting kit-8 (CCK-8) and flow cytometry were used to evaluate the biocompatibility. The osteoblastic differentiation of the MC3T3-E1 cells was also analyzed by quantitative real-time polymerase chain reaction analysis. The CCK-8 and counts of colony-forming units (CFUs) were used to detect the antibacterial activity of the coating on Enterococcus faecalis. The study showed that the cerium oxide-incorporated calcium silicate coating (CeO2-CS) has better biocompatibility. Meanwhile, the ALP, OCN, and BSP mRNA expression levels in the CeO2-CS group were significantly upregulated (P < 0.05). The number of viable bacteria and the CFU results were significantly reduced in the CeO2-CS group (P < 0.05). CONCLUSION: The cerium oxide-incorporated calcium silicate coatings (CeO2-CS) may promote the osteoblastic differentiation of osteoblasts. Meanwhile, the cerium oxide-incorporated calcium silicate coating (CeO2-CS) showed strong antimicrobial activity on E. faecalis, with good biocompatibility.


Assuntos
Anti-Infecciosos , Implantes Dentários , Compostos de Cálcio , Cério , Materiais Revestidos Biocompatíveis , Silicatos
17.
Org Biomol Chem ; 16(36): 6675-6679, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-30175349

RESUMO

A cost-effective system is revealed here to construct polyfunctionalized 2H-pyran cores containing phosphinyl groups with an organobase as a catalyst. Good to excellent yields were obtained under the optimized reaction conditions, with a broad substrate scope tolerated.

18.
Sensors (Basel) ; 18(1)2018 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-29342850

RESUMO

Articulated wheel loaders used in the construction industry are heavy vehicles and have poor stability and a high rate of accidents because of the unpredictable changes of their body posture, mass and centroid position in complex operation environments. This paper presents a novel distributed multi-sensor system for real-time attitude estimation and stability measurement of articulated wheel loaders to improve their safety and stability. Four attitude and heading reference systems (AHRS) are constructed using micro-electro-mechanical system (MEMS) sensors, and installed on the front body, rear body, rear axis and boom of an articulated wheel loader to detect its attitude. A complementary filtering algorithm is deployed for sensor data fusion in the system so that steady state margin angle (SSMA) can be measured in real time and used as the judge index of rollover stability. Experiments are conducted on a prototype wheel loader, and results show that the proposed multi-sensor system is able to detect potential unstable states of an articulated wheel loader in real-time and with high accuracy.

19.
Phys Chem Chem Phys ; 19(16): 10695-10697, 2017 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-27352959

RESUMO

Correction for 'Enhanced room temperature NO2 response of NiO-SnO2 nanocomposites induced by interface bonds at the p-n heterojunction' by Jian Zhang et al., Phys. Chem. Chem. Phys., 2016, 18, 5386-5396.

20.
Chin J Traumatol ; 20(4): 194-197, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28689800

RESUMO

PURPOSE: Skin ulcer is a common type of disease affecting patients' health and quality of life, and bacterial infection increases the difficulty of its management. METHODS: The present study collected the results of bacterial culture sampled from the surface of 110 cases of skin ulcers at our hospital from January 2011 to December 2012. We analyzed the constituent ratios of ulcer surface bacteria, the change in the main infectious bacteria and the results of drug-sensitivity testing for common bacteria. In addition, the characteristics of bacterial infection of skin ulcers were summarized. RESULT: Of the 110 samples, 90 isolated bacteria were cultured. Sixty-one were Gram-negative bacteria, mainly comprising Pseudomonas aeruginosa, Klebsiella pneumoniae, Enterobacter cloacae and Escherichia coli. In addition, 23 isolates were Gram-positive bacteria, mainly comprising Staphylococcus aureus and Enterococcus faecalis. The probability of a negative bacterial culture in 2012 was significantly lower than that in 2011 (16.7% vs. 40.0%, p < 0.01). Moreover, the probability of P. aeruginosa infection in 2012 was significantly higher than that in 2011 (31.7% vs. 14.0%, p < 0.01). P. aeruginosa was resistant to seven commonly used antibiotics. Both K. pneumoniae and E. coli had higher resistance to ampicillin. E. cloacae were not sensitive to piperacillin/tazobactam. Acinetobacter baumannii was resistant to all the tested drugs. S. aureus, E. faecalis and Staphylococcus epidermidis had high resistance to clindamycin. There was other drug resistance to reflect the higher rate of skin bacterial resistance. CONCLUSION: Skin bacterial resistance rate is high. Gram-negative bacteria gradually account for the majority, and P. aeruginosa becomes the most important skin infection pathogen. These characteristics of bacterial infections of skin ulcers provide a significant reference for guiding the selection of antibiotics, better controlling infections of skin ulcers and accelerating the healing of skin ulcers.


Assuntos
Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Úlcera Cutânea/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Úlcera Cutânea/microbiologia , Adulto Jovem
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