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1.
BMC Med Imaging ; 24(1): 124, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38802736

RESUMO

BACKGROUND: The prevalence of hypertensive heart disease (HHD) is high and there is currently no easy way to detect early HHD. Explore the application of radiomics using cardiac magnetic resonance (CMR) non-enhanced cine sequences in diagnosing HHD and latent cardiac changes caused by hypertension. METHODS: 132 patients who underwent CMR scanning were divided into groups: HHD (42), hypertension with normal cardiac structure and function (HWN) group (46), and normal control (NOR) group (44). Myocardial regions of the end-diastolic (ED) and end-systolic (ES) phases of the CMR short-axis cine sequence images were segmented into regions of interest (ROI). Three feature subsets (ED, ES, and ED combined with ES) were established after radiomic least absolute shrinkage and selection operator feature selection. Nine radiomic models were built using random forest (RF), support vector machine (SVM), and naive Bayes. Model performance was analyzed using receiver operating characteristic curves, and metrics like accuracy, area under the curve (AUC), precision, recall, and specificity. RESULTS: The feature subsets included first-order, shape, and texture features. SVM of ED combined with ES achieved the highest accuracy (0.833), with a macro-average AUC of 0.941. AUCs for HHD, HWN, and NOR identification were 0.967, 0.876, and 0.963, respectively. Precisions were 0.972, 0.740, and 0.826; recalls were 0.833, 0.804, and 0.863, respectively; and specificities were 0.989, 0.863, and 0.909, respectively. CONCLUSIONS: Radiomics technology using CMR non-enhanced cine sequences can detect early cardiac changes due to hypertension. It holds promise for future use in screening for latent cardiac damage in early HHD.


Assuntos
Diagnóstico Precoce , Hipertensão , Imagem Cinética por Ressonância Magnética , Humanos , Feminino , Masculino , Imagem Cinética por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Hipertensão/diagnóstico por imagem , Hipertensão/complicações , Máquina de Vetores de Suporte , Cardiopatias/diagnóstico por imagem , Idoso , Adulto , Teorema de Bayes , Curva ROC , Interpretação de Imagem Assistida por Computador/métodos , Radiômica
2.
Glob Chang Biol ; 27(11): 2561-2579, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33666308

RESUMO

A quantitative understanding of physiological thermal responses is vital for forecasting species distributional shifts in response to climate change. Many studies have focused on metabolic rate as a global metric for analyzing the sublethal effects of changing environments on physiology. Thermal performance curves (TPCs) have been suggested as a viable analytical framework, but standard TPCs may not fully capture physiological responses, due in part to failure to consider the process of metabolic depression. We derived a model based on the nonlinear regression of biological temperature-dependent rate processes and built a heart rate data set for 26 species of intertidal molluscs distributed from 33°S to ~40°N. We then calculated physiological thermal performance limits with continuous heating using T 1 / 2 H , the temperature at which heart rate is decreased to 50% of the maximal rate, as a more realistic measure of upper thermal limits. Results indicate that heat-induced metabolic depression of cardiac performance is a common adaptive response that allows tolerance of harsh environments. Furthermore, our model accounted for the high inter-individual variability in the shape of cardiac TPCs. We then used these TPCs to calculate physiological thermal safety margins (pTSM), the difference between the maximal operative temperature (95th percentile of field temperatures) and T 1 / 2 H of each individual. Using pTSMs, we developed a physiological species distribution model (pSDM) to forecast future geographic distributions. pSDM results indicate that climate-induced species range shifts are potentially less severe than predicted by a simple correlative SDM. Species with metabolic depression below the optimum temperature will be more thermal resistant at their warm trailing edges. High intraspecific variability further suggests that models based on species-level vulnerability to environmental change may be problematic. This multi-scale, mechanistic understanding that incorporates metabolic depression and inter-individual variability in thermal response enables better predictions about the relationship between thermal stress and species distributions.


Assuntos
Termotolerância , Adaptação Fisiológica , Mudança Climática , Temperatura Alta , Temperatura
3.
Bioprocess Biosyst Eng ; 43(11): 2017-2026, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32572568

RESUMO

Herein, we reported a green biosynthesis method of copper nanoparticles (CuNPs) at microwave irradiation condition by using pectin as a stabilizer and ascorbic acid as a reducing agent. Under the optimum conditions, CuNPs1 and 2 were synthesized under microwave times 0 and 3 min, respectively. Transmission electron microscope and scanning electron microscope (SEM) tests showed that CuNPs1 and 2 had irregular polygon particles with average diameters of 61.9 ± 19.4 and 40.9 ± 13.6 nm, respectively. Zeta potentials of CuNPs1 and 2 were -45.2 and -48.7 mV, respectively. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and X-ray photoelectron spectroscopy techniques were used to characterize the properties of CuNPs. Furthermore, inhibition zone tests showed that CuNPs2 exhibited higher antimicrobial activities against Escherichia coli, Staphylococcus aureus, and Aspergillus japonicus than CuNPs1. The antibacterial activities were also studied by the bacterial growth kinetics in broth media, and CuNPs2 exhibited lower minimum bactericidal concentrations than CuNPs1.


Assuntos
Anti-Infecciosos/síntese química , Cobre/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Pectinas/química , Antibacterianos/farmacologia , Ácido Ascórbico , Aspergillus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Química Verde , Cinética , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Termogravimetria , Difração de Raios X
4.
Food Chem ; 286: 1-7, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-30827581

RESUMO

Surfactant and microwave assisted extraction (S-MAE) was used for pectin extraction from orange peel. First, we optimized the conditions of microwave assisted extraction (MAE), e.g., irradiation time, liquid-to-solid ratio (LSR), and pH on pectin yield (PY), galacturonic acid (GA) content, and degree of esterification (DE) using a Box-Behnken design. Under optimal conditions (pH 1.2, 7.0 min, and 21.5 v/w LSR), we obtained a PY of 28.0 ±â€¯0.5%, which was close to the predicted value (31.1%). Second, we analyzed the effect of surfactant on microwave extraction of pectin. Among the surfactants investigated, Tween-80 (8 g/L, w/v) increased PY by 17.0%. Compared with conventional solvent extraction, S-MAE is a novel and efficient method for pectin extraction, which generated a higher (p < 0.05) PY (32.8%), GA content (78.1%), DE (69.8%), and Mw (286.3 kDa).


Assuntos
Citrus sinensis/metabolismo , Micro-Ondas , Pectinas/química , Tensoativos/química , Cromatografia Líquida de Alta Pressão , Esterificação , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Pectinas/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier
5.
Ann Hematol ; 97(10): 1809-1816, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29754271

RESUMO

The standard treatment in elderly patients with diffuse large B cell lymphoma (DLBCL) has not yet been finely established. We investigated the efficacy and safety of rituximab with a reduced-dose of EPOCH chemotherapy in elderly patients who had advanced DLBCL with high IPI scores. The dose of 70% EPOCH was given to patients aged 75 to 79 years, and dose of 50% to patients aged over 80 years. Thirty-one patients with a median age of 79 years (range 75-86 years) were enrolled. Patients received a median of 6 cycle's chemotherapy. The complete response rate was 71.0%. The 3-year overall survival (OS) and progression-free survival rates were 62.8 and 60.3%, respectively. The most frequent grade 3/4 adverse effects were neutropenia (3 patients, 7 events), febrile neutropenia (3 patients, 5 events), and pulmonary infection (3 patients, 3 events). Our study showed that ECOG score 3-4, bulky disease, ß2-MG > 5.0 mg/L, and loss of any IADL are prognostic factors for OS in univariate analysis. In summary, reduced-dose EPOCH-R chemotherapy for very elderly patients is very effective with acceptable toxicities. Our preliminary study may provide an alternative approach to manage very elderly fit patients with advanced and poor risk DLBCL by first-line treatment with reduced-dose EPOCH-R.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/patologia , Rituximab/administração & dosagem , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Progressão da Doença , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Estadiamento de Neoplasias , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Prognóstico , Rituximab/efeitos adversos , Resultado do Tratamento , Vincristina/administração & dosagem , Vincristina/efeitos adversos
6.
Food Chem ; 256: 413-418, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29606468

RESUMO

In order to increase the degree of substitution (DS), a combination of heat-moisture treatment (HMT) and octenyl succinylation (OSA) was used to modify sweet potato starch (SPS). The content of OSA had significant influence on the DS of starch, and DS of HMT OSA-modified SPS (HOSA-SPS) was higher than that of OSA-modified SPS (OSA-SPS), indicating that prior HMT could enhance the reaction. HOSA-SPS showed higher contents of SDS and RS in comparison with OSA-SPS as OSA concentration was beyond 6%. HMT decreased swelling power of starch while OSA modification had a contrary role (p < 0.05). Scanning electron microscopy (SEM) showed starch was destroyed by OSA modification while HMT had slight effect on the structure. X-ray diffraction (XRD) indicated that crystal type of starch was transformed from C- to A-type resulted from HMT, and remained unchanged by OSA modification. The onset, peak, and conclusion gelatinization temperatures of starch increased by HMT and decreased by OSA modification (p < 0.05).


Assuntos
Manipulação de Alimentos/métodos , Ipomoea batatas/química , Extratos Vegetais/química , Amido/química , Digestão , Temperatura Alta , Ipomoea batatas/metabolismo , Extratos Vegetais/metabolismo , Amido/metabolismo , Succinatos/química , Difração de Raios X
7.
Medicine (Baltimore) ; 96(52): e9114, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29384901

RESUMO

BACKGROUND: Patients with idiopathic pulmonary fibrosis (IPF) often suffer from progressive worsening of dyspnea and lung function. Although 2 drugs are now available for IPF treatment, many gaps are still to be filled. Evidences suggest that there may be some beneficial effect of acupuncture on pulmonary diseases. This review aims to systematically determine the efficacy and safety of acupuncture for treating IPF. METHODS: The following 8 databases will be searched from their inception to March 20, 2017: PubMed, Embase, Cochrane Central Register of Controlled Trials, Web of Science, Chinese Biomedical Literature Database, China National Knowledge Infrastructure, Chongqing VIP, and Wanfang Data. Randomized controlled trials (RCTs) of acupuncture for IPF without restriction of publication status will be included. Two review authors will independently undertake study selection, extraction of data, and assessment of study quality. Meta-analysis will be conducted after screening of studies if possible. Dichotomous data will be analyzed using odds ratio (OR), and continuous data mean difference (MD). Statistical analysis will be conducted using Review Manager (RevMan) software. RESULTS: This systematic review will provide a detailed summary of the current evidences related to the efficacy and safety of acupuncture in improving breathlessness, exercise limitation, health status impairment of patients with IPF. CONCLUSION: This evidence may be useful to clinicians, patients, and health policy-makers with regard to the use of acupuncture in IPF treatment. ETHICS AND DISSEMINATION: This systematic review will provide up-to-date information on acupuncture for IPF. This review does not require ethical approval and will be disseminated electronically through a peer-reviewed publication or conference presentations. TRIAL REGISTRATION NUMBER: PROSPERO 2017:CRD42017059848.


Assuntos
Terapia por Acupuntura , Fibrose Pulmonar Idiopática/terapia , Humanos , Fibrose Pulmonar Idiopática/complicações , Revisões Sistemáticas como Assunto , Resultado do Tratamento
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(9): 2471-4, 2009 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-19950655

RESUMO

Near-infrared spectroscopy (NIRS) combined with least squares support vector machines (LS-SVM) was used to establish a new method for the determination of the hesperidin content in guogongjiu medicinal wine. Firstly, training set was partitioned by Kernard-Stone (KS) algorithm. Secondly, spectral pretreatment methods were discussed in detail, comparing smoothing, rangescaling, autoscaling, first derivative, second derivative, along with those methods combined. Smoothing, first derivative and rangescaling were used for the pretreatment of the NIR spectra of guogongjiu medicinal wine. Thirdly, the effective interval was selected for 8211-8312 and 9712-9808 cm(-1) by synergy interval partial least squares (siPLS). Finally, the model was established by LS-SVM, the root mean square error of cross validation (RMSECV) is 0.001, root mean square error of prediction (RMSEP) is 0.004, and relative deviation of predicting set is less than 5%. It was compared with siPLS, radial basis function neural network (RBF-NN), and SVM, The result shows that the method is rapid, non-destructive, and credible. It is an effective measurement for determining the hesperidin content in guogongjiu medicinal wine.


Assuntos
Hesperidina/análise , Máquina de Vetores de Suporte , Vinho/análise , Algoritmos , Análise dos Mínimos Quadrados , Redes Neurais de Computação , Espectroscopia de Luz Próxima ao Infravermelho
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