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1.
BMC Cardiovasc Disord ; 23(1): 129, 2023 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-36899310

RESUMO

BACKGROUND: This study aims to investigate the value of myocardial work (MW) parameters during the isovolumic relaxation (IVR) period in patients with left ventricular diastolic dysfunction (LVDD). METHODS: This study prospectively recruited 448 patients with risks for LVDD and 95 healthy subjects. An additional 42 patients with invasive measurements of left ventricular (LV) diastolic function were prospectively included. The MW parameters during IVR were noninvasively measured using EchoPAC. RESULTS: The total myocardial work during IVR (MWIVR), myocardial constructive work during IVR (MCWIVR), myocardial wasted work during IVR (MWWIVR), and myocardial work efficiency during IVR (MWEIVR) of these patients were 122.5 ± 60.1 mmHg%, 85.7 ± 47.8 mmHg%, 36.7 ± 30.6 mmHg%, and 69.4 ± 17.8%, respectively. The MW during IVR was significantly different between patients and healthy subjects. For patients, MWEIVR and MCWIVR were significantly correlated with the LV E/e' ratio and left atrial volume index, MWEIVR exhibited a significant correlation with the maximal rate of decrease in LV pressure (dp/dt per min) and tau, and the MWEIVR corrected by IVRT also exhibited a significant correlation with tau. CONCLUSIONS: MW during IVR significantly changes in patients with risks for LVDD, and is correlated to LV conventional diastolic indices, including dp/dt min and tau. Noninvasive MW during IVR may be a promising tool to evaluate the LV diastolic function.


Assuntos
Disfunção Ventricular Esquerda , Função Ventricular Esquerda , Humanos , Diástole , Miocárdio
2.
Molecules ; 21(12)2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27941614

RESUMO

Since the maximum foaming temperature window is only about 4 °C for supercritical CO2 (scCO2) foaming of pristine polypropylene, it is important to raise the melt strength of polypropylene in order to more easily achieve scCO2 foaming. In this work, radiation cross-linked isotactic polypropylene, assisted by the addition of a polyfunctional monomer (triallylisocyanurate, TAIC), was employed in the scCO2 foaming process in order to understand the benefits of radiation cross-linking. Due to significantly enhanced melt strength and the decreased degree of crystallinity caused by cross-linking, the scCO2 foaming behavior of polypropylene was dramatically changed. The cell size distribution, cell diameter, cell density, volume expansion ratio, and foaming rate of radiation-cross-linked polypropylene under different foaming conditions were analyzed and compared. It was found that radiation cross-linking favors the foamability and formation of well-defined cell structures. The optimal absorbed dose with the addition of 2 wt % TAIC was 30 kGy. Additionally, the foaming temperature window was expanded to about 8 °C, making the handling of scCO2 foaming of isotactic polypropylene much easier.


Assuntos
Compostos Alílicos/química , Dióxido de Carbono/química , Reagentes de Ligações Cruzadas/efeitos da radiação , Polímeros/química , Polipropilenos/química , Dióxido de Carbono/efeitos da radiação , Radioisótopos de Cobalto , Raios gama , Polipropilenos/efeitos da radiação , Temperatura
3.
Plant Sci ; 346: 112162, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38901780

RESUMO

CrRLK1L subfamily members are involved in diverse growth- and development-related processes in Arabidopsis. However, the functions of their counterparts in rice are unknown. Here, OsANX expression was detected in developing inflorescences, mature pollen grains, and growing pollen tubes, and it was localized to the plasma membrane in pollen grains and tobacco epidermal cells. Homozygous osanx progeny could not be segregated from the CRISPR/Cas9-edited mutants osanx-c1+/- and osanx-c2+/-, and such progeny were segregated only occasionally from osanx-c3+/-. Further, all three alleles showed osanx male but not female gamete transmission defects, in line with premature pollen tube rupture in osanx-c3. Additionally, osanx-c3 exhibited precocious flowering, excessively branched inflorescences, and an extremely low seed setting rate of 1.4 %, while osanx-c2+/- and osanx-c3+/- had no obvious defects in inflorescence development or the seed setting rate compared to wild-type Nipponbare (Nip). Consistent with this, the complemented line pPS1:OsANX-GFP/osanx-c2 (PSC), in which the lack of OsANX expression was inflorescence-specific, showed slightly earlier flowering and overly-branched panicles. Multiple inflorescence meristem transition-related and inflorescence architecture-related genes were expressed at higher levels in osanx-c3 than in Nip; thus, they may partially account for the aforementioned mutant phenotypes. Our findings broaden our understanding of the biological functions of OsANX in rice.


Assuntos
Inflorescência , Oryza , Proteínas de Plantas , Tubo Polínico , Oryza/genética , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Oryza/enzimologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Inflorescência/genética , Inflorescência/crescimento & desenvolvimento , Tubo Polínico/crescimento & desenvolvimento , Tubo Polínico/genética , Flores/crescimento & desenvolvimento , Flores/genética , Regulação da Expressão Gênica de Plantas
4.
Plants (Basel) ; 13(6)2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38592851

RESUMO

Receptor kinases DRUS1 (Dwarf and Runtish Spikelet1) and DRUS2 are orthologues of the renowned Arabidopsis thaliana gene FERONIA, which play redundant roles in rice growth and development. Whether the two duplicated genes perform distinct functions in response to environmental stress is largely unknown. Here, we found that osmotic stress (OS) and ABA increased DRUS1 expression while decreasing DRUS2. When subjected to osmotic stress, the increased DRUS1 in drus2 mutants suppresses the OsIAA repressors, resulting in a robust root system with an increased number of adventitious and lateral roots as well as elongated primary, adventitious, and lateral roots, conferring OS tolerance. In contrast, the decreased DRUS2 in drus1-1 mutants are not sufficient to suppress OsIAA repressors, leading to a feeble root system with fewer adventitious and lateral roots and hindering seminal root growth, rendering OS intolerance. All these findings offer valuable insights into the biological significance of the duplication of two homologous genes in rice, wherein, if one is impaired, the other one is able to continue auxin-signaling-mediated root growth and development to favor resilience to environmental stress, such as water shortage.

5.
Am J Chin Med ; 51(2): 373-389, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36655684

RESUMO

Idiopathic Pulmonary Fibrosis (IPF) is identifiable by the excessive increase of mesenchyme paired with the loss of epithelium. Total flavonoids of Astragalus (TFA), the main biologically active ingredient of the traditional Chinese medicine, Astragalus membranaceus (Huangqi), shows outstanding effects on treating pulmonary disorders, including COVID-19-associated pulmonary dysfunctions. This study was designed to evaluate the efficacy of TFA on treating pulmonary fibrosis and the possible mechanisms behind these effects. A549 cells were treated with TGF-[Formula: see text]1 and TFA to observe the potential effects of TFA on regulating alveolar epithelial cell proliferation, TGF-[Formula: see text]1-induced EMT, and the underlying mechanisms in vitro. Then, mouse pulmonary fibrosis was induced with a single intra-tracheal injection of bleomycin, and TFA was administrated by i.p. injection. Lung fibrosis was evaluated through histological and molecular analyses, and the possible mechanisms were explored using immunological methods. The results demonstrated that TFA could promote cell proliferation but inhibit TGF-[Formula: see text]1-induced EMT on A549 cells. TFA attenuated BLM-induced pulmonary fibrosis in mice by modulating inflammatory infiltration and M2 macrophage polarization; it furthermore modulated EMT through regulating the TGF-[Formula: see text]1/Smad pathway. In addition, TFA augmented the expression of the Wnt7b protein, which plays an important role in alveolar epithelium reparation. In conclusion, TFA alleviated bleomycin-induced mouse lung fibrosis by preventing the fibrotic response and increasing epithelium regeneration.


Assuntos
COVID-19 , Fibrose Pulmonar , Camundongos , Animais , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/metabolismo , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Transição Epitelial-Mesenquimal , COVID-19/metabolismo , Fibrose , Bleomicina/efeitos adversos , Epitélio/metabolismo , Epitélio/patologia , Regeneração , Pulmão , Fator de Crescimento Transformador beta1/metabolismo
6.
Eur J Pharmacol ; 961: 176170, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37939991

RESUMO

Heart failure with preserved ejection fraction (HFpEF) represents a multifaceted syndrome related to complex pathologic mechanisms. Sacubitril/valsartan (Sac/val) has demonstrated therapeutic efficacy in HFpEF treatment. However, additional research is required to elucidate its pharmacological mechanisms. Accordingly, this study aimed to explore the potential therapeutic effects of Sac/val in HFpEF rats and the underlying molecular mechanisms. In this study, rats with HFpEF were induced by subjecting spontaneously hypertensive rats to a diet rich in fats, salts, and sugars, along with administering streptozotocin. Subsequently, they were administered Sac/val at a daily dosage of 18 mg/kg. Finally, cardiac structure and function were assessed using echocardiography; Hematoxylin and eosin staining and Masson's trichrome staining were employed to evaluate the pathological changes; Quantitative real-time polymerase chain reaction and Western blot analysis were conducted to determine the expression of pertinent mRNA and proteins. Sac/val treatment attenuated left ventricular (LV) remodeling and diastolic dysfunction in HFpEF rats, possibly related to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic efficacy. Mechanistically, Sac/val might inhibit inflammation by down-regulating cell adhesion molecule (intercellular adhesion molecule-1 (ICAM-1) and vascular endothelial cell adhesion molecule-1 (VCAM-1)) expression. Additionally, it blocked the phosphorylation of glycogen synthase kinase 3ß (GSK-3ß) to prevent cardiomyocyte hypertrophy. Furthermore, it effectively suppressed myocardial fibrosis by inhibiting the transforming growth factor-beta1 (TGF-ß1)/Smads pathway. Our findings suggest that Sac/val improved LV remodeling and diastolic dysfunction, potentially attributed to its anti-inflammatory, anti-hypertrophic, and anti-fibrotic effects. These results provide a sound theoretical rationale for the clinical application of Sac/val in patients with HFpEF.


Assuntos
Insuficiência Cardíaca , Miocardite , Humanos , Animais , Ratos , Volume Sistólico , Glicogênio Sintase Quinase 3 beta , Valsartana/farmacologia , Valsartana/uso terapêutico , Aminobutiratos/farmacologia , Aminobutiratos/uso terapêutico , Compostos de Bifenilo/farmacologia , Fibrose , Hipertrofia/tratamento farmacológico , Inflamação/tratamento farmacológico , Inflamação/patologia , Combinação de Medicamentos , Anti-Inflamatórios/farmacologia
7.
Science ; 375(6587): eabj1711, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35324280

RESUMO

Jeon et al. (Reports, 29 January 2021, p. 498) reported reversible fluctuations between disordered and crystalline states during nucleation. We argue that the adoption of "magic numbers" for separation of the size range into three parts is misleading when using the sigmoid functions and that their figure 3B was wrongly illustrated. The crystal shape effect was neglected during theoretical analysis.


Assuntos
Registros , Cristalização
9.
Environ Sci Pollut Res Int ; 25(11): 11045-11053, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29411276

RESUMO

A novel quaternary ammonium polyethylene nonwoven fabric for removing chromium ions from water was prepared via radiation-induced grafting of glycidyl methacrylate and further modification with N,N'-dimethylethylenediamine. The structural and morphological characteristics of the adsorbent were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetry and differential thermogravimetry (TG/DTG), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The influences of several principal factors, including pH value, initial Cr(VI) concentration, contact time, and coexisting anions (including SO42-, CO32-, NO3-, PO43-, and Cl-), on adsorption performance were investigated via batch tests. The results showed that the optimum removal efficiency was 99.2% at pH 3 and the maximum adsorption quantity for Cr(VI) at 25 °C was 336 mg/g. The adsorption kinetic parameters were better fitted with the pseudo-second-order kinetic model, and the equilibrium data were described very well by the Freundlich isotherm model. Furthermore, the as-synthesized adsorbent exhibited excellent regeneration and recyclability while maintaining high adsorption performance after five adsorption/desorption cycles.


Assuntos
Compostos de Amônio/química , Cromo/química , Compostos de Epóxi/química , Íons/química , Metacrilatos/química , Águas Residuárias/análise , Adsorção , Cinética , Microscopia Eletrônica de Varredura , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Águas Residuárias/química
10.
Exp Ther Med ; 9(6): 2043-2046, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26136933

RESUMO

The aim of the present study was to investigate the incremental value of resting three-dimensional speckle-tracking echocardiography (3D-STE) in the detection of early-stage left ventricular dysfunction in patients with coronary artery disease (CAD). A total of 110 patients suspected of having CAD were recruited. All patients underwent 3D-STE and coronary artery angiography (CAG). They were divided to a CAD group and a normal group according to the results of CAG. Using 3D-STE software, the peak values of longitudinal strain (LS), circumferential strain (CS), radial strain (RS) and area strain (AS) and the time to peak value of these strains (T-LS, T-CS, T-RS and T-AS) were measured. A receiver operator characteristic curve (ROC) was used to analyze the sensitivity of these strains for the diagnosis of CAD. ROC analysis indicated that T-LS and composite indices combining the peak strain value and time to peak of LS, CS and AS have diagnostic value for the early detection of CAD; the area under the curve (AUC) values were 0.667, 0.692, 0.621 and 0.672 respectively (P<0.005). The composite index of longitudinal strain demonstrated the highest diagnostic value for CAD with 62% sensitivity and 76% specificity. These results indicate that 3D-STE has incremental value for the diagnosis of CAD in patients at rest.

11.
Cancer Chemother Pharmacol ; 67(1): 49-56, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20204365

RESUMO

BACKGROUND: Fluoropyrimidine drugs are widely used in head and neck cancer (HNC). DPD deficiency is a pharmacogenetics syndrome associated with severe/lethal toxicities upon 5-FU or capecitabine intake. We have developed a simple, rapid, and inexpensive functional testing for DPD activity, as a means to identify deficient patients and to anticipate subsequent 5-FU-related toxicities. We present here the impact of fluoropyrimidine dose tailoring based on DPD functional screening in a prospective, open, non-controlled study, both in term of reduction in severe toxicities and of treatment efficacy. METHODS: About 65 patients with HNC (59 ± 9 years, 52M/13F, Prospective Group) were entered into the study. Screening for DPD deficiency was performed prior to the beginning of the chemotherapy or radiochemotherapy. DPD status was evaluated by monitoring U/UH2 ratio levels in plasma as a surrogate marker for enzymatic functionality. 5-FU doses were reduced according to the extent of the detected DPD impairment, and adjusted on the basis of age, general condition, and other clinical/paraclinical covariates, if required. Treatment-related toxicities and subsequent impact on treatment delay were carefully monitored next for comparison with a retrospective, Reference subset of 74 other patients with HNC (mean age: 59 ± 10, 58M/16F, Reference Group), previously treated in the same institute with similar schedule but using standard 5-FU dosage. RESULTS: Thirty-one out of 65 patients (48%) were identified as mildly (28%) to markedly (20%) DPD deficient. Subsequently, dose reductions ranging from 10 to 100% with 5-FU were applied in those patients. In this group, six patients (9%) experienced severe toxicities, none of them being life threatening, and no toxic death was encountered. In comparison, 16 out of 74 patients (22%) of the Reference Group displayed severe side effects after standard 5-FU administration, 13% being life-threatening toxicities (e.g., G4 neutropenia + sepsis). Moreover, one toxic death was observed in this Reference Group. No postponement or cancelation of forthcoming chemoradiotherapy courses occurred in the Prospective Group, whereas treatment had to be disrupted in six patients (8%) from the Reference Group. No difference in first-line therapy efficacy was evidenced between the two subsets (78 vs. 79% response, P = 0.790). CONCLUSIONS: Although non-randomized, this study strongly suggests that prospective determination of DPD status has an immediate clinical benefit by reducing the drug-induced toxicities incidence in patients treated with 5-FU, allowing an optimal administration of several courses in a row, while maintaining efficacy. Our preliminary results thus advocate for systematic DPD screening in patients eligible for treatment with fluoropyrimidine drugs in HNC.


Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Deficiência da Di-Hidropirimidina Desidrogenase/genética , Fluoruracila/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Di-Hidrouracila Desidrogenase (NADP)/genética , Relação Dose-Resposta a Droga , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Neoplasias de Cabeça e Pescoço/enzimologia , Humanos , Masculino , Pessoa de Meia-Idade , Farmacogenética , Estudos Prospectivos , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento
12.
Cancer Chemother Pharmacol ; 63(6): 1177-80, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19107485

RESUMO

We report here the case of a 19-year-old female patient who suffered from extremely severe toxicities (G4 mucitis, fever, diarrhea, alteration of general state) while undergoing low-dose capecitabine treatment for her metastatic corticosurrenaloma. The severe toxicities stopped as soon as treatment was suspended. Interestingly, this patient was not deficient in DPD, a pharmacogenetic syndrome usually associated with increased risk of developing severe/lethal toxicities in patients undergoing fluoropyrimidine therapy, and she had been treated previously with 5-FU with a good tolerance. We then hypothesized that cytidine deaminase (CDA) extensive phenotype could be responsible for the severe toxicities observed with capecitabine. CDA is affected by genetic polymorphism, with subsequent acquisition of either deficient or extensive metabolizer profile. Phenotypic investigations confirmed that CDA activity in this patient was +180% higher than the ones usually recorded in the general population. This strongly suggests that the extensive activation of triple-prodrug capecitabine could have occurred in this patient, resulting in overexposure to 5-FU and its cytotoxic metabolites eventually. This case report suggest for the first time that severe toxicities with a capecitabine-containing protocol could be, at least in part, linked with an extensive-CDA syndrome. The case reported here suggests therefore that besides DPD, screening for CDA activity could be of interest to ensure a better safety in the handling of oral capecitabine at the bedside.


Assuntos
Antimetabólitos Antineoplásicos/efeitos adversos , Citidina Desaminase/metabolismo , Desoxicitidina/análogos & derivados , Fluoruracila/análogos & derivados , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/enzimologia , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacocinética , Antimetabólitos Antineoplásicos/uso terapêutico , Capecitabina , Citidina Desaminase/genética , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Desoxicitidina/farmacocinética , Desoxicitidina/uso terapêutico , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/farmacocinética , Fluoruracila/uso terapêutico , Humanos , Taxa de Depuração Metabólica , Polimorfismo Genético , Adulto Jovem
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