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1.
BMC Plant Biol ; 23(1): 311, 2023 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-37308826

RESUMO

BACKGROUND: Cytoplasmic male sterility (CMS) is the basis of heterosis exploitation. CMS has been used to hybrid production in cotton, but its molecular mechanism remains unclear. CMS is associated with advanced or delayed tapetal programmed cell death (PCD), and reactive oxygen species (ROS) may mediate this process. In this study, we obtained Jin A and Yamian A, two CMS lines with different cytoplasmic sources. RESULTS: Compared with maintainer Jin B, Jin A anthers showed advanced tapetal PCD with DNA fragmentation, producing excessive ROS which accumulated around the cell membrane, intercellular space and mitochondrial membrane. The activities of peroxidase (POD) and catalase (CAT) enzymes which can scavenge ROS were significantly decreased. However, Yamian A tapetal PCD was delayed with lower ROS content, and the activities of superoxide dismutase (SOD) and POD were higher than its maintainer. These differences in ROS scavenging enzyme activities may be caused by isoenzyme gene expressions. In addition, we found the excess ROS generated in Jin A mitochondria and ROS overflow from complex III might be the source in parallel with the reduction of ATP content. CONCLUSION: ROS accumulation or abrogation were mainly caused by the joint action of ROS generation and scavenging enzyme activities transformation, which led to the abnormal progression of tapetal PCD, affected the development of microspores, and eventually contributed to male sterility. In Jin A, tapetal PCD in advance might be caused by mitochondrial ROS overproduction, accompanied by energy deficiency. The above studies will provide new insights into the cotton CMS and guide the follow-up research ideas.


Assuntos
Gossypium , Peroxidase , Feminino , Gravidez , Humanos , Espécies Reativas de Oxigênio , Citoplasma , Citosol , Peroxidases , Apoptose
2.
Cell Commun Signal ; 20(1): 62, 2022 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-35534896

RESUMO

BACKGROUND: Recent studies have indicated that some members of the tripartite motif (TRIM) proteins function as important regulators for non-small cell lung cancer (NSCLC), However, the regulatory mechanism underpinning aberrant expression of TRIM in NSCLC remains unclear. Here we report that TRIM15 plays important roles in NSCLC progression through modulating Keap1-Nrf2 signaling pathway. METHODS: TRIM15 expression was evaluated by western blot analysis, tissue microarray-based immunohistochemistry analysis. The interactions between TRIM15 and Keap1 were analyzed by co-immunoprecipitation (Co-IP) and immunofluorescence co-localization assay. The correlation between TRIM15 and Keap1 was measured by Co-IP and ubiquitination analysis in vitro. Gain- and lost-of-function experiments were used to detect TRIM15 promotes proliferation and invasion of NSCLC cells both in vitro and vivo. RESULTS: Here, we revealed that TRIM15 was frequently upregulated in NSCLC samples and associated with poor prognosis. Functionally, TRIM15 knockdown resulted in decreased cancer cell proliferation and metastasis, whereas ectopic TRIM15 expression facilitated tumor cancer cell proliferation and metastasis in vitro and in vivo. Moreover, TRIM15 promoted cell proliferation and metastasis depends on its E3 ubiquitin ligase. Mechanistically, TRIM15 directly targeted Keap1 by ubiquitination and degradation, the principal regulator of Nrf2 degradation, leading to Nrf2 escaping from Keap1-mediated degradation, subsequently promoting antioxidant response and tumor progression. CONCLUSIONS: Therefore, our study characterizes the pivotal roles of TRIM15 promotes NSCLC progression via Nrf2 stability mediated by promoting Keap1 ubiquitination and degradation and could be a valuable prognostic biomarker and a potential therapeutic target in NSCLC. Video Abstract.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Proteínas de Ligação a DNA , Neoplasias Pulmonares , Transdução de Sinais , Ubiquitina-Proteína Ligases , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas de Ligação a DNA/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Neoplasias Pulmonares/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
3.
Ann Clin Microbiol Antimicrob ; 21(1): 12, 2022 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-35303873

RESUMO

BACKGROUND: Legionellosis remains a public health problem. The most common diagnostic method to detect Legionella pneumophila (L. pneumophila) is culture. Polymerase chain reaction (PCR) is a fast and accurate method for this detection in environmental samples. METHODS: Four databases were searched for studies that evaluated the detection efficiency of PCR in L. pneumophila. The quality evaluation was conducted using Review Manager 5.3. We used Meta-DiSc 1.4 software and the Stata 15.0 software to create forest plots, a meta-regression, a bivariate boxplot and a Deeks' funnel plot. RESULTS: A total of 18 four-fold tables from 16 studies were analysed. The overall pooled sensitivity and specificity of PCR was 94% and 72%, respectively. The positive likelihood ratio (RLR) and negative likelihood ratio (NLR) was 2.73 and 0.12, respectively. The result of the diagnostic odds ratio (DOR) was 22.85 and the area under the curve (AUC) was 0.7884. CONCLUSION: Establishing a laboratory diagnostic tool for L. pneumophila detection is important for epidemiological studies. In this work, PCR demonstrated a promising diagnostic accuracy for L. pneumophila.


Assuntos
Legionella pneumophila , Bases de Dados Bibliográficas , Microbiologia Ambiental , Humanos , Legionella pneumophila/genética , Legionella pneumophila/isolamento & purificação , Razão de Chances , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade
4.
Altern Ther Health Med ; 28(6): 156-160, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33128536

RESUMO

A 42-year-old male was hospitalized 13.5 hours after ingestion of 50 mg (approximately 0.7 mg/kg) colchicine in a suicide attempt. The patient developed gastrointestinal dysfunction, grade IV myelosuppression, and restrictive respiratory failure without occurrences of cardiovascular collapse or fatal dysrhythmias. Emergency treatment with integrated Chinese and Western medicine was started and the patient fully recovered without long-term complications. This report describes a massive overdose of colchicine successfully treated with integrated Chinese and Western medicine. Current treatment options are reviewed.


Assuntos
Overdose de Drogas , Gastroenteropatias , Adulto , China , Colchicina , Overdose de Drogas/tratamento farmacológico , Humanos , Masculino , Tentativa de Suicídio
5.
J Acoust Soc Am ; 150(1): 29, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34340476

RESUMO

An MRI-based three-dimensional computer model of a canine larynx was used to investigate the effect of cricothyroid (CT) and thyroarytenoid (TA) muscle activity on vocal fold pre-phonatory posturing and glottic dynamics during voice production. Static vocal fold posturing in the full activation space of CT and TA muscles was first simulated using a laryngeal muscle mechanics model; dynamic flow-structure-acoustics interaction (FSAI) simulations were then performed to predict glottal flow and voice acoustics. The results revealed that TA activation decreased the length and increased the bulging, height, and contact area of the vocal fold. CT activation increased the length and contact area and decreased the height of the vocal fold. Both CT and TA activations increased the vocal fold stress, stiffness, and closure quotient; and only slightly affected the flow rate and voice intensity. Furthermore, CT and TA showed a complex control mechanism on the fundamental frequency pattern, which highly correlated with a combination of the stress, stiffness, and stretch of the vocal fold.


Assuntos
Músculos Laríngeos , Voz , Acústica , Animais , Fenômenos Biomecânicos , Cães , Músculos Laríngeos/diagnóstico por imagem , Fonação , Prega Vocal/diagnóstico por imagem
6.
J Acoust Soc Am ; 150(2): 1176, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34470336

RESUMO

Using a continuum model based on magnetic resonance imaging of a canine larynx, parametric simulations of the vocal fold vibration during phonation were conducted with the cricothyroid muscle (CT) and the thyroarytenoid muscle (TA) independently activated from zero to full activation. The fundamental frequency (f0) first increased and then experienced a downward jump as TA activity gradually increased under moderate to high CT activation. Proper orthogonal decomposition analysis revealed that the vocal fold vibrations were dominated by two modes representing a lateral motion and rotational motion, respectively, and the f0 drop was associated with a switch on the order of the two modes. In another parametric set where only the vocalis was active, f0 increased monotonically with both TA and CT activity and the mode switch did not occur. The results suggested that the active stress in the TA, which causes large stress differences between the body and cover, is essential for the occurrence of the rotational mode and mode switch. Relatively greater TA activity tends to promote the rotational mode, while relatively greater CT activity tends to promote the lateral mode. The results also suggested that the vibration modes affected f0 by affecting the contribution of the TA stress to the effective stiffness. The switch in the dominant mode caused the non-monotonic change of f0.


Assuntos
Músculos Laríngeos , Laringe , Animais , Cães , Músculos Laríngeos/diagnóstico por imagem , Fonação , Vibração , Prega Vocal/diagnóstico por imagem
7.
J Acoust Soc Am ; 147(4): 2597, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32359330

RESUMO

In this work, a high-fidelity three-dimensional continuum model of the canine laryngeal framework was developed for simulating laryngeal posturing. By building each muscle and cartilage from magnetic resonance imaging (MRI), the model is highly realistic in anatomy. The muscle mechanics is modeled using the finite-element method. The model was tested by simulating vocal fold postures under systematic activations of individual as well as groups of laryngeal muscles, and it accurately predicted vocal fold posturing parameters reported from in vivo canine larynges. As a demonstration of its application, the model was then used to investigate muscle controls of arytenoid movements, medial surface morphology, and vocal fold abduction. The results show that the traditionally categorized adductor and abductor muscles can have opposite effects on vocal fold posturing, making highly complex laryngeal adjustments in speech and singing possible. These results demonstrate that a realistic comprehensive larynx model is feasible, which is a critical step toward a causal physics-based model of voice production.


Assuntos
Laringe , Prega Vocal , Animais , Fenômenos Biomecânicos , Cães , Músculos Laríngeos/diagnóstico por imagem , Laringe/diagnóstico por imagem , Imageamento por Ressonância Magnética , Prega Vocal/diagnóstico por imagem , Vocalização Animal
8.
J Sci Food Agric ; 100(5): 2136-2144, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31884697

RESUMO

BACKGROUND: Nitric oxide (NO) and abscisic acid (ABA) are important regulators of plant response to cold stress, and they interact in response to cold signals. The primary goal of this study was to determine the roles of exogenous NO and ABA on the synthesis of endogenous NO and ABA in cold-stored peach fruit. RESULTS: Exogenous NO and ABA maintained a relatively high content of NO, increased nitrate reductase (NR) activity, and inhibited the activity of NO synthase (NOS)-like and the levels of polyamine biosynthesis in peaches during cold storage. Treatments of potassium 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO), NO, N-nitro-l-Arg-methyl ester (L -NAME), and sodium tungstate did not influence ABA content. Exogenous ABA increased the content of carotenoids and the activities of aldehyde oxidase (AO), 9-cis-epoxycarotenoid dioxygenase (NCED), and zeaxanthin epoxidase (ZEP) of ABA synthesis in peaches during cold storage, and upregulated the gene expression of PpAO1, PpNCED1, PpNCED2, and PpZEP. The production of endogenous NO was differentially inhibited by NO scavengers, ABA inhibitors, and NR inhibitors, but not affected by NOS-like inhibitors during cold storage. CONCLUSION: Exogenous NO and ABA can induce endogenous NO synthesis in cold-stored peaches by the nitrate reductase pathway, and ABA can mediate endogenous ABA synthesis by the autocatalytic reaction. NO does not regulate ABA synthesis. © 2019 Society of Chemical Industry.


Assuntos
Ácido Abscísico/metabolismo , Óxido Nítrico/metabolismo , Prunus persica/metabolismo , Adenosilmetionina Descarboxilase/metabolismo , Aldeído Oxidase , Arginina/análise , Carboxiliases/metabolismo , Dioxigenases , Armazenamento de Alimentos , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Nitratos/análise , Óxido Nítrico Sintase/metabolismo , Nitritos/análise , Oxirredutases , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Espermidina/análise , Espermina/análise
9.
J Cell Mol Med ; 23(2): 1458-1469, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30515965

RESUMO

Lung cancer (LC) is a devastating malignancy with no effective treatments, due to its complex genomic profile. Using bioinformatics analysis and immunohistochemical of lung carcinoma tissues, we show that TRIM59 as a critical oncoprotein relating to LC proliferation and metastasis. In this study, high TRIM59 expression was significantly correlated with lymph node metastasis, distant metastasis, and tumour stage. Furthermore, up-regulation of TRIM59 expression correlated with poorer outcomes in LC patients. Mechanistically, TRIM59 play a key role in promoting LC growth and metastasis through regulation of extracellular-signal regulated protein kinase (ERK) signalling pathway and epithelial-to-mesenchymal transition (EMT)-markers, as validated by loss-of-function studies. In-depth bioinformatics analysis showed that there is preliminary evidence of co-expression of TRIM59 and cyclin dependent kinase 6 (CDK6) in LC. Notably, CDK6 expression significantly decreased when TRIM59 was knocked down in the LC cells. In contrast, exogenous up-regulation of TRIM59 expression also induced significant increases in the expression of CDK6. Moreover, the expression of CDK6 was also inhibited by the ERK signalling inhibitor, U0126. The results of both loss- and gain-of-function studies showed that TRIM59 could regulate the expression of CDK6. Collectively, these data provide evidence that TRIM59 is involved in lung carcinoma growth and progression possibly through the induction of CDK6 expression and EMT process by activation of ERK pathway.


Assuntos
Carcinoma/genética , Quinase 6 Dependente de Ciclina/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Pulmonares/genética , Proteínas com Motivo Tripartido/genética , Biomarcadores Tumorais/genética , Butadienos/farmacologia , Carcinoma/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metástase Neoplásica , Nitrilas/farmacologia , Transdução de Sinais
10.
J Cell Mol Med ; 23(1): 293-305, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30394687

RESUMO

Gastric cancer (GC) is a malignancy of the lining of the stomach and is prone to distant metastasis, which involves a variety of complex molecules. The S100 proteins are a family of calcium-binding cytosolic proteins that possess a wide range of intracellular and extracellular functions and play pivotal roles in the invasion and migration of tumour cells. Among these, S100A10 is known to be overexpressed in GC. Lysine succinylation, a recently identified form of protein post-translational modification, is an important regulator of cellular processes. Here, we demonstrated that S100A10 was succinylated at lysine residue 47 (K47), and levels of succinylated S100A10 were increased in human GC. Moreover, K47 succinylation of S100A10 was stabilized by suppression of ubiquitylation and subsequent proteasomal degradation. Furthermore, carnitine palmitoyltransferase 1A (CPT1A) was found to function as a lysine succinyltransferase that interacts with S100A10. Succinylation of S100A10 is regulated by CPT1A, while desuccinylation is regulated by SIRT5. Overexpression of a succinylation mimetic mutant, K47E S100A10, increased cell invasion and migration. Taken together, this study reveals a novel mechanism of S100A10 accumulation mediated by succinylation in GC, which promotes GC progression and is regulated by the succinyltransferase CPT1A and SIRT5-mediated desuccinylation.


Assuntos
Anexina A2/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Proteínas S100/metabolismo , Neoplasias Gástricas/patologia , Animais , Anexina A2/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Lisina/metabolismo , Masculino , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Processamento de Proteína Pós-Traducional , Proteínas S100/genética , Sirtuínas/metabolismo , Neoplasias Gástricas/metabolismo , Succinatos/metabolismo
11.
Hepatology ; 67(5): 1943-1955, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29220536

RESUMO

The scavenger receptor CD36 recognizes a diverse set of ligands and has been implicated in a wide variety of normal and pathological processes, including lipid metabolism, angiogenesis, atherosclerosis, and phagocytosis. In particular, recent findings have demonstrated its crucial functions in sterile inflammation and tumor metastasis. However, the role of CD36 in immune-mediated hepatitis remains unclear. Concanavalin A (ConA)-induced liver injury is a well-established experimental T cell-mediated hepatitis. To understand the role of CD36 in hepatitis, we tested the susceptibility of CD36-deficient (CD36-/- ) mice to this model, evaluated by a liver enzyme test, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay, histological analysis, mononuclear cell (MNC) infiltration, and hepatic proinflammatory factor production. CD36-/- mice were less sensitive to ConA-induced hepatitis and had a significantly lower number of liver MNCs (LMNCs), including CD4+ cells, CD8+ T cells, natural killer cells, natural killer T cells, infiltrating macrophages, and neutrophils, as well as reduced expression of inflammatory mediators (tumor necrosis factor α, CXC chemokine ligand (CXCL) 10, interleukin (IL)-1α, monocyte chemotactic protein 1, and IL-6) compared with controls. Notably, we used bone marrow chimeric mice to demonstrate that CD36 expression on nonhematopoietic cells was required to drive ConA-induced liver injury. Furthermore, our data show that the CD36 receptor was essential for CXCL10-induced hepatocyte apoptosis and activation of IκB kinase, Akt, and Jun N-terminal kinase. Moreover, treatment of wild-type mice with genistein, a tyrosine kinase inhibitor that blocks CD36-Lyn signaling, attenuated ConA-induced liver injury and reduced the number of MNCs. CONCLUSIONS: Our findings suggest that CD36 plays an important proinflammatory role in ConA-induced liver injury by promoting hepatic inflammation and mediating the proapoptotic effect of chemokine CXCL10, and therefore, may be a potential therapeutic target for immune-mediated hepatitis. (Hepatology 2018;67:1943-1955).


Assuntos
Transtornos Plaquetários/patologia , Antígenos CD36/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Quimiocina CXCL10/metabolismo , Doenças Genéticas Inatas/patologia , Hepatite/metabolismo , Animais , Apoptose/efeitos dos fármacos , Transtornos Plaquetários/imunologia , Doença Hepática Induzida por Substâncias e Drogas/patologia , Concanavalina A/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Citometria de Fluxo , Doenças Genéticas Inatas/imunologia , Genisteína/farmacologia , Hepatite/imunologia , Hepatite/patologia , Hepatócitos/metabolismo , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Transdução de Sinais
12.
J Sci Food Agric ; 99(7): 3367-3380, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30584803

RESUMO

BACKGROUND: Cold conditions can accelerate the production of reactive oxygen species (ROS), and excessive ROS may attack biological macromolecules, disrupt related signal pathways, induce oxidative stress and influence plant metabolism. The cross-talk between nitric oxide (NO) and abscisic acid (ABA) and the inhibitions by NO or ABA on oxidative damage have been reported in fruits. However, there are few reports about the roles of NO-ABA interactions in chilling stress and antioxidant defense in fruits during cold storage. This study was conducted to investigate the roles of NO, ABA and interactions between NO and ABA in response to chilling stress on peach fruit (Prunus persica (L.) Batsch, cv. 'Xintaihong'). RESULTS: Treatments with 15 µmol L-1 NO, 100 µmol L-1 ABA and 15 µmol L-1 NO + 5 mmol L-1 sodium tungstate solution could reduce ROS content, alleviate lipid peroxidation and enhance antioxidant enzyme activities and antioxidant capacities. However, treatments with 5 µmol L-1 potassium 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO), 5 mmol L-1 sodium tungstate and 100 µmol L-1 ABA + 5 µmol L-1 c-PTIO differentially blocked these protective effects and significantly increased ROS content and lipid peroxidation of peaches under low-temperature conditions. CONCLUSIONS: Application of exogenous ABA could increase the resistance to cold-induced oxidative stress by enhancing the efficiency of enzymatic and non-enzymatic systems, which were partially mediated by NO. © 2018 Society of Chemical Industry.


Assuntos
Ácido Abscísico/farmacologia , Frutas/efeitos dos fármacos , Óxido Nítrico/farmacologia , Prunus persica/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Antioxidantes/metabolismo , Temperatura Baixa , Armazenamento de Alimentos , Frutas/química , Frutas/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Prunus persica/química , Prunus persica/efeitos dos fármacos
13.
J Cell Mol Med ; 22(11): 5708-5719, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30160350

RESUMO

Helicobacter pylori (H. pylori) infection triggers chronic inflammation that has been associated with gastric cancer (GC). Exosomes are small extracellular vesicles that have become the key mediators of intercellular communication. In this study, we investigated exosome-mediated communication between H. pylori-infected GC cells and macrophages, focusing on the transfer of activated mesenchymal-epithelial transition factor (MET). We observed a significant decrease in MET protein expression in GC cells after infection with H. pylori, whereas MET mRNA levels remained unchanged. Intriguingly, MET expression, specifically the phosphorylated active form, was increased in exosomes released from H. pylori-infected GC cells. Confocal microscopy and Western blotting analyses showed that these exosomes containing MET were delivered to and internalized by macrophages. Indeed, in human GC tissues positive for H. pylori, we also observed that activated MET was highly expressed in tumour-infiltrating macrophages. After internalization, exosomal MET then appeared to educate the macrophages towards a pro-tumorigenesis phenotype. This included exosomal MET-mediated stimulation of proinflammatory cytokine secretion IL-1ß, which subsequently promoted tumour growth and progression in vitro and in vivo. Taken together, these data were the first to demonstrate H. pylori infection-induced upregulation of activated MET in exosomes and the pro-tumorigenic effect on tumour-associated macrophages.


Assuntos
Infecções por Helicobacter/genética , Inflamação/genética , Proteínas Proto-Oncogênicas c-met/genética , Neoplasias Gástricas/genética , Animais , Linhagem Celular Tumoral , Progressão da Doença , Transição Epitelial-Mesenquimal/genética , Exossomos/genética , Exossomos/microbiologia , Mucosa Gástrica/microbiologia , Mucosa Gástrica/patologia , Regulação Neoplásica da Expressão Gênica , Infecções por Helicobacter/complicações , Infecções por Helicobacter/microbiologia , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Xenoenxertos , Humanos , Inflamação/microbiologia , Inflamação/patologia , Interleucina-1beta/genética , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Neoplasias Gástricas/complicações , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
14.
J Acoust Soc Am ; 141(4): EL351, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28464635

RESUMO

A finite element method based numerical indentation technique was used to quantify the effect of the material stiffness variation and the subglottal convergence angle of the vocal fold on the vertical stiffness difference of the medial surface. It was found that the vertical stiffness difference increased with the increasing subglottal angle, and it tended to saturate beyond a subglottal angle of about 50°. The material stiffness variation could be as important as the subglottal angle depending on the actual material properties.


Assuntos
Simulação por Computador , Modelos Teóricos , Fonação , Prega Vocal/fisiologia , Fenômenos Biomecânicos , Elasticidade , Análise de Elementos Finitos , Humanos , Movimento , Análise Numérica Assistida por Computador , Vibração , Prega Vocal/anatomia & histologia
15.
J Acoust Soc Am ; 140(4): 2856, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27794296

RESUMO

A parametric study was conducted using the numerical technique that coupled a three-dimensional continuum vocal fold model with a one-dimensional Bernoulli flow model to investigate the effect of vocal fold vertical stiffness variation on voice production. Vertical stiffness gradient was defined as the ratio of the inferior-superior stiffness difference to the mean stiffness and was introduced in the cover layer. The results showed that increasing the vertical stiffness gradient would increase the peak flow rate and sound intensity and decrease the open quotient and threshold pressure. The effect was found to be more prominent at low subglottal pressures. The underlying mechanism might be that the reduced stiffness at the superior aspect of the vocal fold would allow a larger lateral displacement and result in a larger vibration. Increasing the vertical stiffness gradient was also found to increase the vertical phase difference and glottal divergent angle during the vocal fold vibration. Meanwhile, increasing the vertical stiffness variation only slightly increased the mean flow rate, which is important to maintaining the speech time between breaths.


Assuntos
Prega Vocal , Glote , Humanos , Masculino , Fonação , Vibração , Voz
16.
Biochem Biophys Res Commun ; 444(3): 346-53, 2014 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-24462865

RESUMO

Salvianolic acid B (SalB), one of the major bioactive components in Salviamiltiorrhiza, has plenty of cardioprotective effects. The present study was designed to investigate the effect of SalB on angiotensin II (AngII)-induced hypertrophy in neonatal rat cardiomyocytes, and to find out whether or not this effect is attributed to inhibition of poly (ADP-ribose) polymerase-1 (PARP-1), which plays a key role in cardiac hypertrophy. Our results showed that SalB prevented the cardiomyocytes from AngII-induced hypertrophy, associated with attenuation of the mRNA expressions of atrial natriuretic factor and brain natriuretic peptide, and reduction in the cell surface area. SalB inhibited the activity of PARP-1. The inhibitory effect was comparable to that of the PARP-1 inhibitor 3-Aminobenzamide (3-AB). In addition, SalB reversed the depletion of cellular NAD(+) induced by AngII. Moreover, overexpression of PARP-1 attenuated the anti-hypertrophic effect of SalB. These observations suggested that SalB prevented the cardiomyocytes from AngII-induced hypertrophy, at least partially through inhibition of PARP-1. Moreover, SalB attenuated the generation of oxidative stress via suppression of NADPH oxidase 2 and 4, which might probably contribute to the inhibition of PARP-1. These present findings may shed new light on the understanding of the cardioprotective effect of SalB.


Assuntos
Angiotensina II/farmacologia , Benzofuranos/farmacologia , Cardiomegalia/prevenção & controle , Miócitos Cardíacos/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases , Animais , Cardiomegalia/induzido quimicamente , Células Cultivadas , NAD/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
17.
Biochem Biophys Res Commun ; 430(3): 944-50, 2013 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-23261455

RESUMO

Poly(ADP-ribosyl)ation catalyzed by the poly(ADP-ribose) polymerases (PARPs) is an immediate post-translational modification of proteins with a homopolymeric chain of repeating ADP-ribose units. It is involved in various cellular processes, such as cell survival and death, transcription, DNA repair and cell division. Inhibitors of PARPs have been documented to be useful in different pathological conditions. Recently, activation of PARP-1, the founding member of PARP family, has been revealed to participate in the development and progression of cardiac hypertrophy and heart failure. However, the roles of other PARPs in cardiovascular system remain to be clarified. PARP-2 shares 69% similarity with PARP-1 in catalytic domains, but their functions do not fully overlap. In this study, we show the first evidence that PARP-2 is involved in cardiac hypertrophy. The mRNA and protein levels of PARP-2 were significantly increased in AngII-stimulated rat cardiomyocytes as well as in hearts of rats submitted to pressure overload. PARP-2 knockdown protected cardiomyocytes from hypertrophy, which may be attributed to activation of SIRT1. These findings shed new light on the understanding of PARP-2-related cardiomyopathy, and suggest the potential application of PARP-2 inhibitors in cardiac hypertrophy.


Assuntos
Cardiomegalia/enzimologia , Miócitos Cardíacos/enzimologia , Inibidores de Poli(ADP-Ribose) Polimerases , Sirtuína 1/biossíntese , Angiotensina II/farmacologia , Animais , Cardiomegalia/genética , Cardiomegalia/patologia , Células Cultivadas , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , Poli(ADP-Ribose) Polimerases/genética , RNA Interferente Pequeno/genética , Ratos , Ratos Sprague-Dawley , Sirtuína 1/genética , Transfecção
18.
Heliyon ; 9(12): e22686, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38213600

RESUMO

In this present age, innovation has become inextricably tied to both long-term economic growth and environmentally sound development. In this context, the impact that environmentally focused technological advancements or innovations have on environmental quality is of the utmost importance. Therefore, the main goal of the present study is to determine how Green innovation (GI) affects environmental degradation in the BRICS countries from 1992 to 2021. The ecological footprint (EFT) is an indicator used in the study to measure environmental degradation. The study divides the components that contribute to the explanation into two categories: the GI threshold variable and the independent variables RE, GDP, and population (POP). Additionally, this study investigates the indirect impact of RE, GDP, and POP through the threshold effect of GI. The stochastic impacts of the explanatory factors are explored using sophisticated panel data estimation methods and a panel threshold model. According to the findings of the study, an improvement in environmental quality occurs when the threshold level of GI is achieved, which indicates that innovation in the form of a lower EFT is responsible for the improvement. In light of the findings, recommendations for policymakers and stakeholders in BRICS countries are to promote RE and drive GI.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37459263

RESUMO

Broad learning system (BLS), which emerges as a lightweight network paradigm, has recently attracted great attention for recognition problems due to its good balance between efficiency and accuracy. However, the supervision mechanism in BLS and its variants generally relies on the strict binary label matrix, which imposes limitations on approximation and fails to adequately align with the data distribution. To address this issue, in this article, two novel flexible label-induced BLS models with the manifold manner are proposed, whose notable characteristics are as follows. First, two proposed label relaxation strategies can both enlarge the margins between different categories and simultaneously enhance the diversity within labels. Second, the integration of manifold geometrical criterion enables the models to capture local feature structures, ensuring the obtained flexible labels align better with the similarity between samples. Third, the proposed models can be optimized efficiently with the alternating direction method of multipliers. Each iteration benefits from a closed-form solution, facilitating the optimization process. Extensive experiments and thorough theoretical analysis are intended to show the advantages of our proposed models compared to other state-of-the-art recognition algorithms.

20.
Commun Biol ; 6(1): 541, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-37208428

RESUMO

Tissue dynamics play critical roles in many physiological functions and provide important metrics for clinical diagnosis. Capturing real-time high-resolution 3D images of tissue dynamics, however, remains a challenge. This study presents a hybrid physics-informed neural network algorithm that infers 3D flow-induced tissue dynamics and other physical quantities from sparse 2D images. The algorithm combines a recurrent neural network model of soft tissue with a differentiable fluid solver, leveraging prior knowledge in solid mechanics to project the governing equation on a discrete eigen space. The algorithm uses a Long-short-term memory-based recurrent encoder-decoder connected with a fully connected neural network to capture the temporal dependence of flow-structure-interaction. The effectiveness and merit of the proposed algorithm is demonstrated on synthetic data from a canine vocal fold model and experimental data from excised pigeon syringes. The results showed that the algorithm accurately reconstructs 3D vocal dynamics, aerodynamics, and acoustics from sparse 2D vibration profiles.


Assuntos
Redes Neurais de Computação , Prega Vocal , Animais , Cães , Prega Vocal/fisiologia , Imageamento Tridimensional , Algoritmos , Física
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