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1.
Am Heart J ; 274: 65-74, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38701961

RESUMO

BACKGROUND: There has not been a consensus on the prothesis sizing strategy in type 0 bicuspid aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR). Modifications to standard annular sizing strategies might be required due to the distinct anatomical characteristics. We have devised a downsizing strategy for TAVR using a self-expanding valve specifically for patients with type 0 bicuspid AS. The primary aim of this study is to compare the safety and efficacy of downsizing strategy with the Standard Annulus Sizing Strategy in TAVR for patients with type 0 bicuspid AS. TRIAL DESIGN: It is a prospective, multi-center, superiority, single-blinded, randomized controlled trial comparing the Down Sizing and Standard Annulus Sizing Strategy in patients with type 0 bicuspid aortic stenosis undergoing transcatheter aortic valve replacement. Eligible participants will include patients with severe type 0 bicuspid AS, as defined by criteria such as mean gradient across aortic valve ≥40 mmHg, peak aortic jet velocity ≥4.0 m/s, aortic valve area (AVA) ≤1.0 cm², or AVA index ≤0.6 cm2/m2. These patients will be randomly assigned, in a 1:1 ratio, to either the Down Sizing Strategy group or the Standard Sizing Strategy group. In the Down Sizing Strategy group, a valve one size smaller will be implanted if the "waist sign" manifests along with less than mild regurgitation during balloon pre-dilatation. The primary end point of the study is a composite of VARC-3 defined device success, absence of both permanent pacemaker implantation due to high-degree atrioventricular block and new-onset complete left bundle branch block. CONCLUSION: This study will compare the safety and efficacy of Down Sizing Strategy with the Standard Annulus Sizing Strategy and provide valuable insights into the optimal approach for sizing in TAVR patients with type 0 bicuspid AS. We hypothesize that the Down Sizing Strategy will demonstrate superiority when compared to the Standard Annulus Sizing Strategy. (Down Sizing Strategy (HANGZHOU Solution) vs Standard Sizing Strategy TAVR in Bicuspid Aortic Stenosis (Type 0) (TAILOR-TAVR), NCT05511792).


Assuntos
Estenose da Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Próteses Valvulares Cardíacas , Desenho de Prótese , Substituição da Valva Aórtica Transcateter , Feminino , Humanos , Masculino , Valva Aórtica/cirurgia , Valva Aórtica/anormalidades , Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Doença da Válvula Aórtica Bicúspide/cirurgia , Doença da Válvula Aórtica Bicúspide/complicações , Estudos Prospectivos , Método Simples-Cego , Substituição da Valva Aórtica Transcateter/métodos
2.
Bioorg Chem ; 147: 107374, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636433

RESUMO

The incidence of idiopathic pulmonary fibrosis (IPF) has been steadily increasing each year, posing significant challenges in its treatment. In this study, we conducted the design and synthesis of 23 new inhibitors that specifically target the TGF-ß1/Smad3 pathway. Initially, we employed a cell model of TGF-ß-induced pulmonary fibrosis, using cell survival rate and HYP expression as indicators to identify the potent ingredient 5aa, which demonstrated significant anti-pulmonary fibrosis activity. Subsequently, we induced mice with bleomycin (BLM) to establish an experimental animal model of pulmonary fibrosis, and evaluated the pharmacodynamics of 5aa in vivo against pulmonary fibrosis. The alterations in HYP and collagen levels in BLM-induced pulmonary fibrosis mice were analyzed using ELISA and immunohistochemistry techniques. The results indicated that compound 5aa effectively suppressed the fibrotic response induced by TGF-ß1, inhibited the expression of the fibrotic marker α-SMA, and hindered the EMT process in NIH3T3 cells. Additionally, oral administration of 5aa demonstrated significant therapeutic effects in a mouse model of IPF, comparable to the established drug Nintedanib. Moreover, compound 5aa exhibited higher bioavailability in vivo compared to Nintedanib. These collective outcomes suggest that 5aa holds promise as a potential inhibitor of TGF-ß1/Smad3 signaling for the treatment of IPF.


Assuntos
Fibrose Pulmonar Idiopática , Transdução de Sinais , Proteína Smad3 , Fator de Crescimento Transformador beta1 , Animais , Proteína Smad3/metabolismo , Proteína Smad3/antagonistas & inibidores , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/patologia , Fibrose Pulmonar Idiopática/induzido quimicamente , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Camundongos , Transdução de Sinais/efeitos dos fármacos , Estrutura Molecular , Humanos , Bleomicina , Relação Estrutura-Atividade , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Relação Dose-Resposta a Droga , Masculino
3.
J Invertebr Pathol ; 204: 108082, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38447863

RESUMO

A specific strain of Vibrio parahaemolyticus (VpAHPND) causes acute hepatopancreatic necrosis disease (AHPND), leading to significant losses in shrimp aquaculture. Outer membrane vesicles (OMVs) are naturally secreted by Gram-negative bacteria, and their significant roles in host-pathogen interactions and pathogenicity have been recognized. In the present study, OMVs were isolated from VpAHPND by differential-ultracentrifugation and used for proteomics analysis. In the Nano-HPLC-MS/MS analysis, totally 645 proteins were determined, including virulence factors, immunogenic proteins, outer membrane protein, bacterial secretory proteins, ribosomal proteins, protease, and iron regulation proteins. Furthermore, GO and KEGG annotations indicated that proteins identified in VpAHPND-OMVs are involved in metabolism, regulation of multiple biological processes, genetic information processes, immunity and more. Meanwhile, toxin proteins PirAvp and PirBvp, associated with VpAHPND pathogenicity, were also identified in the proteome of VpAHPND-OMVs. Our objective is to identify the protein composition of OMVs released by VpAHPND, analyzing the potential for cytotoxicity and immunomodulatory activity of these granule hosts. This study is crucial for understanding the roles played by bacterial-derived vesicles in the disease process, given that these vesicles carry relevant activities inherent to the bacteria that produce them.


Assuntos
Penaeidae , Proteoma , Vibrio parahaemolyticus , Vibrio parahaemolyticus/patogenicidade , Proteoma/análise , Animais , Penaeidae/microbiologia , Hepatopâncreas/microbiologia , Hepatopâncreas/patologia , Proteínas da Membrana Bacteriana Externa/metabolismo , Proteômica , Vibrioses/veterinária , Vibrioses/microbiologia , Vesículas Extracelulares/metabolismo
4.
J Med Internet Res ; 26: e41843, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39028996

RESUMO

BACKGROUND: There are limited data available on the development of arrhythmias in patients at risk of high-degree atrioventricular block (HAVB) or complete heart block (CHB) following transcatheter aortic valve replacement (TAVR). OBJECTIVE: This study aimed to explore the incidence and evolution of arrhythmias by monitoring patients at risk of HAVB or CHB after TAVR using smartwatches. METHODS: We analyzed 188 consecutive patients in the prospective SMART TAVR (smartwatch-facilitated early discharge in patients undergoing TAVR) trial. Patients were divided into 2 groups according to the risk of HAVB or CHB. Patients were required to trigger a single-lead electrocardiogram (ECG) recording and send it to the Heart Health App via their smartphone. Physicians in the central ECG core lab would then analyze the ECG. The incidence and timing of arrhythmias and pacemaker implantation within a 30-day follow-up were compared. All arrhythmic events were adjudicated in a central ECG core lab. RESULTS: The mean age of the patients was 73.1 (SD 7.3) years, of whom 105 (55.9%) were men. The mean discharge day after TAVR was 2.0 (SD 1.8) days. There were no statistically significant changes in the evolution of atrial fibrillation or atrial flutter, Mobitz I, Mobitz II, and third-degree atrial ventricular block over time in the first month after TAVR. The incidence of the left bundle branch block (LBBB) increased in the first week and decreased in the subsequent 3 weeks significantly (P<.001). Patients at higher risk of HAVB or CHB received more pacemaker implantation after discharge (n=8, 9.6% vs n=2, 1.9%; P=.04). The incidence of LBBB was higher in the group with higher HAVB or CHB risk (n=47, 56.6% vs n=34, 32.4%; P=.001). The independent predictors for pacemaker implantation were age, baseline atrial fibrillation, baseline right bundle branch block, Mobitz II, and third-degree atrioventricular block detected by the smartwatch. CONCLUSIONS: Except for LBBB, no change in arrhythmias was observed over time in the first month after TAVR. A higher incidence of pacemaker implantation after discharge was observed in patients at risk of HAVB or CHB. However, Mobitz II and third-degree atrioventricular block detected by the smartwatch during follow-ups were more valuable indicators to predict pacemaker implantation after discharge from the index TAVR. TRIAL REGISTRATION: ClinicalTrials.gov NCT04454177; https://clinicaltrials.gov/study/NCT04454177.


Assuntos
Arritmias Cardíacas , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Masculino , Feminino , Idoso , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Estudos Prospectivos , Idoso de 80 Anos ou mais , Eletrocardiografia , Bloqueio Atrioventricular/etiologia , Bloqueio Atrioventricular/terapia
5.
FASEB J ; 35(2): e21183, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33184978

RESUMO

Calcific aortic valve disease (CAVD) is the most common valvular heart disease in adults. The cellular mechanisms of CAVD are still unknown, but accumulating evidence has revealed that osteogenic differentiation of human valve interstitial cells (hVICs) plays an important role in CAVD. Thus, we aimed to investigate the function of estrogen-related receptor α (ERRα) in the osteogenic differentiation of hVICs. We found that the level of ERRα was significantly increased in CAVD samples compared to normal controls. In addition, ERRα was significantly upregulated during hVIC osteogenic differentiation in vitro. Gain- and loss-of-function experiments were performed to identify the function of ERRα in hVIC calcification in vitro. Inhibition of endogenous ERRα attenuated hVIC calcification, whereas overexpression of ERRα in hVICs promoted this process. RNA sequencing results suggested that heme oxygenase-1 (Hmox1) was a downstream target of ERRα, which was further confirmed by western blotting. Additionally, we also found that downregulation of Hmox1 by shHmox1 efficiently reversed the inhibition of calcification induced by ERRα shRNA in hVICs. ChIP-qPCR and luciferase assays indicated that Hmox1 was negatively regulated by ERRα. We found that overexpression of Hmox1 or its substrates significantly inhibited hVIC calcification in vitro. In conclusion, we found that knockdown of ERRα can inhibit hVIC calcification through upregulating Hmox1 and that ERRα and Hmox1 are potential targets for the treatment of CAVD.


Assuntos
Estenose da Valva Aórtica/metabolismo , Valva Aórtica/patologia , Calcinose/metabolismo , Técnicas de Silenciamento de Genes , Heme Oxigenase-1/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Idoso , Valva Aórtica/metabolismo , Estenose da Valva Aórtica/patologia , Calcinose/patologia , Diferenciação Celular/genética , Feminino , Células HEK293 , Heme Oxigenase-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Osteogênese/genética , Transfecção , Regulação para Cima/genética , Calcificação Vascular , Receptor ERRalfa Relacionado ao Estrogênio
6.
Crit Rev Food Sci Nutr ; : 1-16, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36476145

RESUMO

Milk contaminated with trace amounts of foodborne pathogens can considerably threaten food safety and public health. Therefore, rapid and accurate detection techniques for foodborne pathogens in milk are essential. Nucleic acid amplification (NAA)-based strategies are widely used to detect foodborne pathogens in milk. This review article covers the mechanisms of the NAA-based detection of foodborne pathogens in milk, including polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), recombinase polymerase amplification (RPA), rolling circle amplification (RCA), and enzyme-free amplification, among others. Key factors affecting detection efficiency and the advantages and disadvantages of the above techniques are analyzed. Potential on-site detection tools based on NAA are outlined. We found that NAA-based strategies were effective in detecting foodborne pathogens in milk. Among them, PCR was the most reliable. LAMP showed high specificity, whereas RPA and RCA were most suitable for on-site and in-situ detection, respectively, and enzyme-free amplification was more economical. However, factors such as sample separation, nucleic acid target conversion, and signal transduction affected efficiency of NAA-based strategies. The lack of simple and effective sample separation methods to reduce the effect of milk matrices on detection efficiency was noteworthy. Further research should focus on simplifying, integrating, and miniaturizing microfluidic on-site detection platforms.

7.
Fish Shellfish Immunol ; 131: 498-504, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36280128

RESUMO

Exosomes are extracellular vesicles secreted by diverse cell under normal or abnormal physiological conditions, which could carry a range of bioactive molecules and play significant roles in biological processes, such as intercellular communication and immune response. In the current study, a preliminary study was performed to investigate the exosomal shuttle protein in Chlamys farreri (designated as CfesPro) and to predict the potential function of exosomes in scallop innate immunity. The serum derived exosomes (designated as CfEVs) were obtained from lipopolysaccharide (LPS)-stimulated C. farreri and untreated ones. After confirmation and characterization by transmission electron microscopy (TEM), nano-HPLC-MS/MS spectrometry was performed on CfEVs using a label-free quantitative method. Totally 2481 exosomal shuttle proteins were identified in CfEVs proteomic data, which included many innate immune related proteins. GO and KOG functional annotation showed that CfesPro participated in cellular processes, metabolism reactions, signaling transductions, immune responses and so on. Moreover, 1421 proteins in CfesPro were enriched to 324 pathways by KEGG analysis, including several immune-related pathways, such as autophagy, apoptosis and lysosome pathway. Meanwhile, eight autophagy-related proteins were initially identified in CfesPro, indicating that CfEVs had a potential role with autophagy. All these findings showed that CfEVs were involved in C. farreri innate immune defenses. This research would enrich the protein database of marine exosomes and provide a basis for the exploration of immune defense systems in marine invertebrates.


Assuntos
Pectinidae , Proteômica , Animais , Espectrometria de Massas em Tandem , Proteínas/metabolismo , Imunidade Inata
8.
J Phys Chem A ; 126(3): 453-461, 2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35023742

RESUMO

A joint experimental and theoretical investigation of the valence shell excitations of carbon tetrachloride has been performed by fast electron scattering and time dependent density functional theory calculations. At a collision energy of 1.5 keV and an energy resolution of about 70 meV, the dipole-forbidden transition of a1σ* ← 2t1 has been clearly observed at large momentum transfers, and its excitation energy of 6.15 eV and line width of 0.72 eV have been determined. Two new features are also recognized at 9.97 and 10.26 eV. The generalized oscillator strengths of the excited states at 5-11.3 eV have been determined from the measured spectra. The calculated generalized oscillator strength of the a1σ* ← 2t1 transition with the vibronic effect shows better agreement with the experiment, and the vibronic effect also accounts for its nonzero intensity at zero squared momentum transfer. The optical oscillator strengths of the valence shell excitations have also been obtained by extrapolating the generalized oscillator strengths to the limit of zero squared momentum transfer. The integral cross sections have been systematically determined from the threshold to 5000 eV by means of the BE-scaling method. The present oscillator strengths and cross sections provide the fundamental data of carbon tetrachloride and have important applications in photochemical modeling for atmospheric physics.

9.
BMC Cardiovasc Disord ; 22(1): 164, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35413789

RESUMO

BACKGROUND: Unlike N-terminal pro-B-type natriuretic peptide (NT-proBNP), which have been extensively studied, little is known about the role of N-terminal pro-C-type natriuretic peptide (NT-proCNP) for predicting survival post transcatheter aortic valve replacement (TAVR). METHODS: A total of 309 patients were included in the analysis. Patients were grouped into quartiles (Q1-4) according to the baseline NT-proCNP value. Blood for NT-proCNP analysis was obtained prior to TAVR procedure. The primary endpoint was mortality after a median follow-up of 32 months. Multivariable Cox proportional hazards regression models analyzed prognostic factors. The predictive capability was compared between NT-proBNP and NT-proCNP using receiver operator curve (ROC) analysis. RESULTS: A total of 309 subjects with the mean age of 76.8 ± 6.3 years, among whom 58.6% were male, were included in the analysis. A total of 58 (18.8%) patients died during follow-up. Cox multivariable analyses indicated society of thoracic surgeons (STS)-score was a strong independent predictor for mortality (hazard ratio (HR) 1.08, 95% confidential interval (CI) 1.05-1.12, P < 0.001). Elevated NT-proCNP was associated with a higher risk of cardiovascular mortality (HR 1.02, 95% CI 1.00-1.03, P = 0.025) and All-cause mortality (HR 1.01, 95% CI 1.00-1.03, P = 0.027), whereas NT-proBNP showed a small effect size on mortality. ROC analysis indicated that NT-proCNP was superior to NT-proBNP for TAVR risk evaluation in patients with left ventricular ejection fraction (LVEF) < 50% [(Area under the curve (AUC)-values of 0.79 (0.69; 0.87) vs. 0.59 (0.48; 0.69), P = 0.0453]. CONCLUSIONS: NT-proCNP and STS-Score were the independent prognostic factors of mortality among TAVR patients. Furthermore, NT-proCNP was superior to NT-proBNP for TAVR risk evaluation in patients with LVEF < 50%. Trial registration NCT02803294, 16/06/2016.


Assuntos
Substituição da Valva Aórtica Transcateter , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Diuréticos , Humanos , Masculino , Peptídeo Natriurético Encefálico , Peptídeo Natriurético Tipo C , Fragmentos de Peptídeos , Prognóstico , Volume Sistólico , Substituição da Valva Aórtica Transcateter/efeitos adversos , Vasodilatadores , Função Ventricular Esquerda
10.
J Integr Plant Biol ; 64(5): 1116-1130, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35293133

RESUMO

Rice OsLIC encoding a CCCH zinc finger transcription factor plays an important role in immunity. However, the immune signaling pathways that OsLIC-involved and the underlying mechanisms that OsLIC-conferred resistance against pathogens are largely unclear. Here, we show that OsLIC, as a substrate for OsMAPK6, negatively regulates resistance to Xanthomonas oryzae pv. oryzae (Xoo) and X. oryzae pv. oryzicola (Xoc) by directly suppressing OsWRKY30 transcription. Biochemical assays showed that OsLIC bound to OsWRKY30 promoter and suppressed its transcription. Genetic assays confirmed that the osilc knockout mutants and OsWRKY30-overexpressing plants exhibited enhanced resistance to Xoo and Xoc, knocking out OsWRKY30 in the oslic mutants attenuated the resistance against bacterial pathogens. OsMAPK6 physically interacted with and phosphorylated OsLIC leading to decreased OsLIC DNA-binding activity, therefore, overexpression of OsLIC partially suppressed OsMAPK6-mediated rice resistance. In addition, both OsMAPK6-phosphorylated activation of OsLIC and phosphorylation-mimic OsLIC5D had reduced DNA-binding activity towards OsWRKY30 promoter, thereby promoting OsWRKY30 transcription. Collectively, these results reveal that OsMAPK6-mediated phosphorylation of OsLIC positively regulates rice resistance to Xoo and Xoc by modulating OsWRKY30 transcription, suggesting that OsMAPK6-OsLIC-OsWRKY30 module is an immune signaling pathway in response to the bacterial pathogens.


Assuntos
Oryza , Xanthomonas , DNA/metabolismo , Oryza/microbiologia , Doenças das Plantas/microbiologia , Dedos de Zinco
11.
BMC Dev Biol ; 21(1): 9, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33879064

RESUMO

BACKGROUND: Yaks have a strong adaptability to the plateau environment, which can be attributed to the effective oxygen utilization rate of their lung tissue. Elastic fibre confers an important adaptive structure to the alveolar tissues in yaks. However, little research has been focused on the structural development of lung tissues and the expression levels of elastic fibres in yaks after birth. Therefore, this study aimed to investigate the morphological changes of elastic fibers and expression profiles of fibre-formation genes in yak lungs at different growth stages and the relationship between these changes and plateau adaptation. RESULTS: Histological staining was employed to observe the morphological changes in the lung tissue structure of yaks at four different ages: 1 day old, 30 days old, 180 days old and adult. There was no significant difference in the area of a single alveolus between the 1-day-old and 30-day-old groups (P-value > 0.05). However, the single alveolar area was gradually increased with an increase in age (P-value < 0.05). Elastic fibre staining revealed that the amount of elastic fibres in alveolar tissue was increased significantly from the ages of 30 days to 180 days (P-value < 0.05) and stabilized during the adult stage. Transcriptome analysis indicated that the highest levels of differentially expressed genes were found between 30 days of age and 180 days of age. KEGG analysis showed that PI3K-Akt signalling pathway and MAPK pathway, which are involved in fibre formation, accounted for the largest proportion of differentially expressed genes between 30 days of age and 180 days of age. The expression levels of 36 genes related to elastic fibre formation and collagen fibre formation were also analysed, and most of these genes were highly expressed in 30-day-old and 180-day-old yaks. CONCLUSIONS: The content of elastic fibres in the alveolar tissue of yaks increases significantly after birth, but this change occurs only from 30 days of age to 180 days of age. Our study indicates that elastic fibres can improve the efficiency of oxygen utilization in yaks under harsh environmental conditions.


Assuntos
Tecido Elástico , Pulmão/crescimento & desenvolvimento , Animais , Bovinos , Perfilação da Expressão Gênica , Morfogênese
12.
Opt Lett ; 46(2): 186-189, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33448984

RESUMO

Time-domain analysis (TDA) is useful for measuring optical devices along with a link and for diagnosing a long device. In this Letter, an optical vector analyzer with TDA capability is proposed and experimentally demonstrated. The key to realizing TDA is a low-coherence optical carrier, which is achieved by modulating an electrical broadband signal on a continuous-wave light via acousto-optic modulation. Then, optical single-sideband modulation and vector balanced detection are used to measure the total frequency response of multiple devices under test (DUTs). Through an inverse Fourier transform, the obtained DUT impulses are distinguished in the time domain. Finally, time-domain gating and Fourier transform are applied to extract the frequency response of each DUT. An experiment is performed in which a fiber link comprising three DUTs and an H 13 C 14 N gas cell with a breakpoint inserted is characterized. The frequency setting resolution is 5 MHz, and a time-domain resolution of 30.84 ns is proved, which can reach 14.881 ns in theory.

13.
Opt Lett ; 46(8): 1856-1859, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33857086

RESUMO

High-performance electro-optical (E-O), opto-electronic (O-E), and optical (O-O) devices are widely used in optical communications, microwave photonics, fiber sensors, and so on. Measurement of the amplitude and phase responses are essential for the development and fabrication of these devices. However, the previous methods can hardly characterize the E-O, O-E, and O-O devices with arbitrary responses. Here we propose a comprehensive vector analyzer based on optical asymmetrical double-sideband (ADSB) modulation to overcome this difficulty. The ADSB solves the problem of frequency aliasing and can extract information from both the +1st- and -1st-order sidebands. Thus, most devices in photonic applications, including phase modulators, can be characterized. In the experiment, a commercial photodetector, a phase modulator, and a sampled FBG are used as the O-E, E-O, and O-O devices under test, respectively. A frequency resolution of 2 MHz, an electrical sweeping range of 40 GHz, and an optical sweeping range of 80 GHz are achieved.

14.
J Dairy Sci ; 104(6): 6577-6587, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33741157

RESUMO

Bacillus cereus is one of the most important spoilage microorganisms in milk. The heat-resistant protease produced is the main factor that causes rotten, bitter off-flavors and age gelation during the shelf-life of milk. In this study, 55 strains of B. cereus were evaluated, of which 25 strains with protease production ability were used to investigate proteolytic activity and protease heat resistance. The results showed that B. cereus C58 had strong protease activity, and its protease also had the highest thermal stability after heat treatment of 70°C (30 min) and 100°C (10 min). The protease was identified as protease HhoA, with a molecular mass of 43.907 kDa. The protease activity of B. cereus C58 in UHT-sterilized whole milk (UHT milk) showed an increase with the growth of bacteria, especially during the logarithmic growth phase. In addition, the UHT milk incubated with protease from B. cereus C58 at 28°C (24 h) and 10°C (6 d) were used to evaluate the effects of protease on the quality of UHT milk, including protein hydrolysis and physical stability. The results showed that the hydrolysis of casein was κ-CN, ß-CN, and αS-CN successively, whereas whey protein was not hydrolyzed. The degree of protein hydrolysis, viscosity, and particle size of the UHT milk increased. The changes in protein and fat contents indicated that fat globules floated at 28°C and settled at 10°C, respectively. Meanwhile, confocal laser scanning microscopy images revealed that the protease caused the stability of UHT milk to decrease, thus forming age gelation.


Assuntos
Bacillus cereus , Leite , Animais , Temperatura Alta , Peptídeo Hidrolases , Temperatura
15.
J Dairy Sci ; 104(11): 11348-11367, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34364644

RESUMO

Members of the Cronobacter genus include food-borne pathogens that can cause infections in infants, with a mortality rate as high as 40 to 80%. The high fatality rate of Cronobacter and its isolation from numerous types of food, especially from powdered infant formula, demonstrate the serious nature of this organism. The source tracking of Cronobacter spp. and the analysis of high-frequency species from different sources are helpful for a more targeted control. Furthermore, the persistence during food processing and storage may be attributed to strong resistance of Cronobacter spp. to environment stresses such as heat, pH, and desiccation. There are many factors that support the survival of Cronobacter spp. in harsh environments, such as some genes, regulatory systems, and biofilms. Advanced detection technology is helpful for the strict monitoring of Cronobacter spp. In addition to the traditional heat treatment, many new control techniques have been developed, and the ability to control Cronobacter spp. has been demonstrated. The control of this bacteria is required not only during manufacture, but also through the selection of packaging methods to reduce postprocessing contamination. At the same time, the effect of inactivation methods on product quality and safety must be considered. This review considers the advances in our understanding of environmental stress response in Cronobacter spp. with special emphasis on its implications in food processing.


Assuntos
Cronobacter sakazakii , Cronobacter , Animais , Cronobacter/genética , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Fórmulas Infantis , Pós
16.
Int J Mol Sci ; 22(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562367

RESUMO

The mitogen-activated protein kinase (MAPK) cascades have been validated playing critical roles in diverse aspects of plant biology, from growth and developmental regulation, biotic and abiotic stress responses, to phytohormone signal transduction or responses. A classical MAPK cascade consists of a MAPK kinase kinase (MAPKKK), a MAPK kinase (MAPKK), and a MAPK. From the 75 MAPKKKs, eight MAPKKs, and 15 MAPKs of rice, a number of them have been functionally deciphered. Here, we update recent advances in knowledge of the roles of rice MAPK cascades, including their components and complicated action modes, their diversified functions controlling rice growth and developmental responses, coordinating resistance to biotic and abiotic stress, and conducting phytohormone signal transduction. Moreover, we summarize several complete MAPK cascades that harbor OsMAPKKK-OsMAPKK-OsMAPK, their interaction with different upstream components and their phosphorylation of diverse downstream substrates to fulfill their multiple roles. Furthermore, we state a comparison of networks of rice MAPK cascades from signal transduction crosstalk to the precise selection of downstream substrates. Additionally, we discuss putative concerns for elucidating the underlying molecular mechanisms and molecular functions of rice MAPK cascades in the future.


Assuntos
Regulação da Expressão Gênica de Plantas , Sistema de Sinalização das MAP Quinases , Oryza/metabolismo , Proteínas de Plantas/metabolismo , Oryza/genética , Oryza/crescimento & desenvolvimento , Proteínas de Plantas/genética , Transdução de Sinais
17.
J Integr Plant Biol ; 63(10): 1815-1842, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34270159

RESUMO

Mitogen-activated protein kinase kinase kinase (MAPKKK) are the first components of MAPK cascades, which play pivotal roles in signaling during plant development and physiological processes. The genome of rice encodes 75 MAPKKKs, of which 43 are Raf-like MAPKKKs. The functions and action modes of most of the Raf-like MAPKKKs, whether they function as bona fide MAPKKKs and which are their downstream MAPKKs, are largely unknown. Here, we identified the osmapkkk43 mutant, which conferred broad-spectrum resistance to Xanthomonas oryzae pv. oryzae (Xoo), the destructive bacterial pathogen of rice. Oryza sativa (Os)MAPKKK43 encoding a Raf-like MAPKKK was previously known as Increased Leaf Angle 1 (OsILA1). Genetic analysis indicated that OsILA1 functioned as a negative regulator and acted upstream of the OsMAPKK4-OsMAPK6 cascade in rice-Xoo interactions. Unlike classical MAPKKKs, OsILA1 mainly phosphorylated the threonine 34 site at the N-terminal domain of OsMAPKK4, which possibly influenced the stability of OsMAPKK4. The N-terminal domain of OsILA1 is required for its homodimer formation and its full phosphorylation capacity. Taken together, our findings reveal that OsILA1 acts as a negative regulator of the OsMAPKK4-OsMAPK6 cascade and is involved in rice-Xoo interactions.


Assuntos
Resistência à Doença , MAP Quinase Quinase Quinases/metabolismo , Sistema de Sinalização das MAP Quinases , Oryza/enzimologia , Xanthomonas , Interações Hospedeiro-Patógeno , MAP Quinase Quinase 4/metabolismo , Proteína Quinase 6 Ativada por Mitógeno/metabolismo
18.
J Phys Chem A ; 124(52): 10997-11005, 2020 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-33347306

RESUMO

The valence-shell excitations of hydrogen sulfide have been studied by fast electron impact at a collision energy of 1.5 keV and an energy resolution of about 70 meV. By analyzing the variations of intensity and shape of the feature in the range of 5.0-7.5 eV at different scattering angles, the excitation energy of 5.85 ± 0.01 eV and the line width of 0.80 ± 0.01 eV of the 3b21A2 state have been determined. The generalized oscillator strengths of the valence-shell excitations in the energy range of 5.0-9.2 eV of hydrogen sulfide have been determined from the measured spectra. The corresponding optical oscillator strengths have been obtained by extrapolating the generalized oscillator strengths to the limit of zero squared momentum transfer. The integral cross sections have also been systematically determined from the threshold to 5000 eV by means of the BE-scaling method. The presently obtained oscillator strengths and integral cross sections have significant applications in the studies of planetary atmospheres and interstellar gases.

19.
Cell Physiol Biochem ; 49(5): 1999-2011, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30235443

RESUMO

BACKGROUND/AIMS: Histone deacetylases (HDACs) play a critical role in the regulation of gene transcription, cardiac development, and diseases. The aim of this study was to investigate whether the inhibition of HDACs improves cardiac remodeling and its underlying mechanisms in a mouse myocardial infarction (MI) model. METHODS: The HDAC inhibitor trichostatin A (TSA, 0.1 mg/kg/day) was administered via daily intraperitoneal injections for 8 consecutive weeks after MI in C57/BL mice. Echocardiography and tissue histopathology were used to assess cardiac function. Cultured neonatal rat cardiac fibroblasts (NRCFs) were subjected to simulated hypoxia in vitro. Autophagic flux was measured using the tandem fluorescent mCherry-GFP-LC3 assay. Western blot was used to detect autophagic biomarkers. RESULTS: After 8 weeks, the inhibition of HDACs in vivo resulted in improved cardiac remodeling and hence better ventricular function. MI was associated with increased LC3-II expression and the accumulation of autophagy adaptor protein p62, indicating impaired autophagic flux, which was reversed by TSA treatment. Cultured NRCFs exhibited increased cell death after simulated hypoxia in vitro. Increased cell death was associated with markedly increased numbers of autophagosomes but not autolysosomes, as assessed by punctate dual fluorescent mCherry-green fluorescent protein tandem-tagged light chain-3 expression, indicating that hypoxia resulted in impaired autophagic flux. Importantly, TSA treatment reversed hypoxia-induced impaired autophagic flux and led to a 40% decrease in cell death. This was accompanied by improved mitochondrial membrane potential. The beneficial effects of TSA therapy were abolished by RNAi intervention targeting LAMP2; likewise, in vivo delivery of chloroquine abolished the TSA-mediated cardioprotective effects. CONCLUSION: Our results provide evidence that the HDAC inhibitor TSA prevents cardiac remodeling after MI and is dependent on restoring autophagosome processing of cardiac fibroblasts.


Assuntos
Autofagossomos/metabolismo , Autofagia/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/metabolismo , Remodelação Ventricular/efeitos dos fármacos , Animais , Apoptose/efeitos dos fármacos , Hipóxia Celular , Fibroblastos/citologia , Fibroblastos/metabolismo , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/química , Ácidos Hidroxâmicos/farmacologia , Ácidos Hidroxâmicos/uso terapêutico , Proteína 2 de Membrana Associada ao Lisossomo/antagonistas & inibidores , Proteína 2 de Membrana Associada ao Lisossomo/genética , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Associadas aos Microtúbulos/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Miócitos Cardíacos/citologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos
20.
Cardiology ; 141(3): 132-140, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30517917

RESUMO

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is a recent and an effective treatment option for high- or extreme-surgical-risk patients with symptomatic severe aortic stenosis. However, pure severe native aortic valve regurgitation (NAVR) without aortic stenosis remains a contraindication to TAVR. The aim of our systemic review analysis was to evaluate TAVR in patients with pure NAVR. METHODS: We searched the published articles in the PubMed and Web of Science databases (2002-2017) using the Boolean operators for studies of NAVR patients undergoing TAVR. Reference lists of all returned articles were searched recursively for other relevant citations. Pooled estimates were calculated using a random-effects meta-analysis. RESULTS: Finally, a total of 10 studies were included in this analysis. The CoreValve was more frequently used with a lower rate of device success and a higher rate of residual aortic regurgitation. The new-generation transcatheter heart valves (THVs) performed a significantly higher rate with less residual aortic regurgitation and a success rate close to 100%. The 30-day all-cause mortality rates ranged from 0 to 30% with an estimate summary rate of 9% (95% CI: 5-15%; I2 = 33%). Cerebrovascular events, major or life-threatening bleeding, major vascular complications, acute kidney disease, and new permanent pacemaker implantation occurred similarly in both the new- and old-generation THV devices. CONCLUSIONS: Aortic regurgitation remains a challenging pathology for TAVR. TAVR is a feasible and reasonable option for carefully selected patients with pure aortic regurgitation.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Próteses Valvulares Cardíacas , Falha de Prótese , Substituição da Valva Aórtica Transcateter/instrumentação , Valva Aórtica/fisiopatologia , Insuficiência da Valva Aórtica/mortalidade , Humanos , Fatores de Risco , Fatores de Tempo , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/mortalidade , Resultado do Tratamento
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