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1.
BMC Med Imaging ; 24(1): 18, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216885

RESUMO

BACKGROUND: To find a useful hypoxia non-invasive biomarker for evaluating early treatment response and prognosis to definitive chemoradiotherapy (dCRT) in patients with esophageal squamous cell carcinoma (ESCC), using blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI). METHODS: The R2* values were obtained pre- and 2-3 weeks post-dCRT in 28 patients with ESCC using BOLD MRI. Independent samples t-test (normality) or Mann-Whitney U test (non-normality) was used to compare the differences of R2*-related parameters between the complete response (CR) and the non-CR groups. Diagnostic performance of parameters in predicting response was tested with receiver operating characteristic (ROC) curve analysis. The 3-year overall survival (OS) was evaluated using Kaplan Meier curve, log rank test, and Cox proportional hazards regression analysis. RESULTS: The post-R2*, ∆R2*, and ∆%R2* in the CR group were significantly higher than those in the non-CR group (P = 0.002, 0.003, and 0.006, respectively). The R2*-related parameters showed good prediction of tumor response, with AUC ranging from 0.813 to 0.829. The 3-year OS rate in patients with ∆R2* >-7.54 s- 1 or CR were significantly longer than those with ∆R2* ≤ -7.54 s- 1 (72.37% vs. 0.00%; Hazard ratio, HR = 0.196; 95% confidence interval, 95% CI = 0.047-0.807; P = 0.024) or non-CR (76.47% vs. 29.27%; HR = 0.238, 95% CI = 0.059-0.963; P = 0.044). CONCLUSIONS: The preliminary results demonstrated that the R2* value might be a useful hypoxia non-invasive biomarker for assessing response and prognosis of ESCC treated with dCRT. BOLD MRI might be used as a potential tool for evaluating tumor oxygenation metabolism, which is routinely applied in clinical practice and beneficial to clinical decision-making. A large sample size was needed for further follow-up studies to confirm the findings.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/terapia , Prognóstico , Quimiorradioterapia/métodos , Biomarcadores , Imageamento por Ressonância Magnética/métodos , Hipóxia/tratamento farmacológico , Estudos Retrospectivos
2.
J Int Econ ; 143: 103766, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37192871

RESUMO

We utilize the global natural experiment created by the COVID-19 outbreak to identify sovereign borrowing capacity in time of need and its determinants. First, we demonstrate that the pandemic creates exogeneous shocks to sovereign borrowing needs-governments borrowed more when hit by more severe pandemic shocks. Second, we show that credible fiscal rules enhance sovereign borrowing capacity, while unsustainable debts in terms of high debt-to-GDP ratio, rollover risk, and sovereign default risk weaken it. Third, we find that, in response to the same pandemic shock, sovereign spreads increase more in emerging economies than advanced economies though the former borrow less during the pandemic. Finally, further analysis reveals that pegged exchange rate regimes, open capital accounts, and monetary dependence improve emerging economies' borrowing capacity.

3.
Ren Fail ; 44(1): 741-747, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35509178

RESUMO

OBJECTIVE: This is the first study to explore the risk factors for nephropathy caused by gadolinium-based contrast agents and establish a prediction model to identify high-risk patients. METHODS: A total of 1404 patients who received gadolinium-based contrast agents in our hospital were included. The participants were randomly assigned in a 7:3 ratio to the modeling and validation groups. The modeling group was divided into a contrast-induced nephropathy group and a non-contrast-induced nephropathy group. The clinical characteristics before the use of contrast agents were compared between the two groups. The risk factors for contrast-induced nephropathy were analyzed by logistic regression. A nomogram that could predict the incidence of contrast-induced nephropathy was plotted. The validation group was used to verify the predictive model. RESULTS: The incidence of contrast-induced nephropathy caused by gadolinium-based contrast agents was 3.92% (55/1404). The logistic stepwise regression analysis showed that sex, systolic pressure (SBP), absolute neutrophil count, albumin, fasting blood glucose level, and furosemide use were significant predictors of contrast-induced nephropathy caused by gadolinium-based contrast agents. The above predictors were then included in the nomogram construction. The area under the receiver operating characteristic (ROC) curve was 0.82 (p < 0.001). The specificity and sensitivity corresponding to the optimal cutoff point (0.039) based on the area under the ROC curve were 71.9% and 80.5%, respectively. CONCLUSION: Sex, SBP, absolute neutrophil count, albumin, fasting blood glucose levels, and furosemide use are significant predictors of contrast-induced nephropathy caused by gadolinium-based contrast agents. Therefore, the incidence of contrast-induced nephropathy may be estimated by the prediction model established in this study before the use of contrast agents.


Assuntos
Meios de Contraste , Nefropatias , Albuminas , Glicemia , Meios de Contraste/efeitos adversos , Feminino , Furosemida , Gadolínio/efeitos adversos , Humanos , Nefropatias/induzido quimicamente , Masculino , Curva ROC , Estudos Retrospectivos , Fatores de Risco
4.
Plant Dis ; 105(8): 2222-2230, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33048591

RESUMO

Black spot, caused by Alternaria alternata, poses a severe threat to the industry of Dendrobium officinale, a Chinese indigenous medicinal herb. Dicarboximide fungicides (DCFs) have been intensively used to control this disease for decades in China, and offer excellent efficacy. The resistance of phytopathogenic pathogens against DCFs are reportedly selected in fields; however, the DCF resistance of A. alternata from D. officinale is not well understood. The isolates of A. alternata with low procymidone resistance (ProLR) were detected in the commercial orchards of D. officinale in China in 2018 and biochemically characterized in this study. The result showed that the ProLR isolates were selected in the commercial orchards with a resistance frequency of 100%, and no significant difference in mycelial growth, sporulation, and virulence was observed among the ProLR and procymidone-sensitive (ProS) isolates. A positive cross-resistance pattern was exhibited between procymidone and iprodione. Results of amino acid sequence alignment of AaOS-1 from the tested isolates showed that all of the ProLR genotypes could be categorized into two groups, including group I (mutations at AaOs-1) and group II (no mutation). Under procymidone (5.0 µg/ml) treatment conditions, the AaOs-1 expression levels increased in the ProS isolates and ranged from approximately 2.94- to 3.69-fold higher than those under procymidone-free conditions, while the AaOs-1 expressions of the ProLR isolates were significantly lower than those in the ProS isolates under the same conditions. The data indicated that the mutations at AaOs-1 are involved in the DCF resistance of A. alternata selected in the D. officinale orchards.


Assuntos
Dendrobium , Plantas Medicinais , Alternaria/genética , Farmacorresistência Fúngica/genética
5.
Plant Dis ; 105(7): 1951-1959, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33044142

RESUMO

Garlic leaf blight caused by Stemphylium eturmiunum was first reported in Jiangsu Province in China. The dicarboximide fungicide (DCF) procymidone is reported to possess broad-spectrum action in inhibiting filamentous fungi and is widely used to control leaf disease of various plants. Of 41 Stemphylium eturmiunum isolates collected in this study from commercial garlic farms in Pizhou and Dafeng counties of Jiangsu Province, eight isolates were resistant to procymidone. The following three phenotypes were categorized according to in vitro responses to DCFs: sensitive, low resistance to iprodione and procymidone, and high resistance to all iprodione and procymidone. The fitness of all resistant isolates was decreased in accordance with data on mycelial growth, conidiation, and virulence. After treatment with 10 µg/ml of procymidone for 4 h, mycelial intracellular glycerol concentrations of resistant isolates were significantly lower than those of sensitive isolates. Positive cross-resistance was observed between dicarboximides and phenylpyrroles, but there was no cross-resistance between dicarboximides and fluazinam or difenoconazole in the two resistant phenotypes. Nucleotide sequence alignment of two-component histidine kinase genes from sensitive and resistant isolates indicated that amino acid mutations were located at the histidine kinase, adenylyl cyclase, methyl-accepting chemotaxis protein and at the phosphatase domain of the N-terminal region and the response regulator domain of the C-terminal region. To our knowledge, this is the first report of DCF resistance in Stemphylium eturmiunum, and these findings will help establish a rational strategy to manage DCF-resistant populations of Stemphylium eturmiunum in the field.


Assuntos
Ascomicetos , Alho , Ascomicetos/genética , Compostos Bicíclicos com Pontes , Farmacorresistência Fúngica/genética
7.
Analyst ; 145(11): 3871-3877, 2020 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-32296795

RESUMO

In this work, a simple and sensitive method based on the inner filter effect (IFE) of p-nitrophenol (PNP) on the fluorescence of gold nanoclusters (AuNCs) has been developed for detecting alkaline phosphatase (ALP) activity. Bright orange fluorescent AuNCs were synthesized by one-pot synthesis and used directly as IFE fluorophores. p-Nitrophenyl phosphate (PNPP) is hydrolyzed by ALP to PNP, which quenches the fluorescence of AuNCs by the IFE. In the presence of ALP, PNPP was converted to PNP, and the absorption band shifted from 310 nm to 405 nm, which resulted in a certain degree of overlap between the absorption of PNP and the excitation of AuNCs. Due to the competitive absorption between AuNCs and PNP, the excitation of AuNCs was clearly diminished, leading to the quenching of the fluorescence of AuNCs. The IFE detection method exhibited a good linear relationship between 0.01 and 7.0 U L-1 (R2 = 0.9990) with the lowest detection limit of 0.003 U L-1 (the signal-to-noise ratio is 3). The proposed detection method was successfully applied for detecting ALP in serum samples and studying ALP inhibitors.


Assuntos
Fosfatase Alcalina/sangue , Ensaios Enzimáticos/métodos , Nanopartículas Metálicas/química , Fosfatase Alcalina/antagonistas & inibidores , Fosfatase Alcalina/química , Inibidores Enzimáticos/química , Fluorescência , Ouro/química , Humanos , Limite de Detecção , Nitrofenóis/química , Compostos Organofosforados/química , Espectrometria de Fluorescência/métodos , Vanadatos/química
8.
Ann Vasc Surg ; 63: 287-292, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31536798

RESUMO

BACKGROUND: There are no available guidelines regarding preserving or ligating an arteriovenous fistula following successful kidney transplantation. Therefore, we performed a meta-analysis to formulate a clear opinion regarding the status of arteriovenous fistula in renal allograft recipients. METHODS: We performed an electronic literature search of PubMed, EMBASE, and the Cochrane Library for eligible studies up to January 2019. We aimed to systematically evaluate cardiac systolic and diastolic function and allograft function after arteriovenous fistula closure. The primary outcome was the differences in left ventricular mass index, left ventricular end-diastolic diameter, ejection fraction, and serum creatinine levels between patients with occluded arteriovenous fistula versus patent arteriovenous fistula. RESULTS: Renal transplant recipients with occluded arteriovenous fistula had lower left ventricular mass index values and left ventricular end-diastolic diameter compared with those with patent arteriovenous fistula. The pooled mean differences were 21.67 (95% confidence interval [CI] 19.94 to 23.39, P < 0.001) and 2.75 (95% CI 1.47 to 4.04, P < 0.001), respectively. Patients with occluded arteriovenous fistula also had lower serum creatinine levels versus those with patent arteriovenous fistula. The pooled mean difference was 0.10 (95% CI 0.04 to 0.17, P = 0.003). We saw no difference regarding ejection fraction between the groups. The pooled mean difference was 0.84 (95% CI -0.85 to 2.53, P = 0.33). CONCLUSIONS: Our meta-analysis demonstrated that arteriovenous fistula closure improves cardiac morphology and has better kidney graft function. Arteriovenous fistula closure may be considered in patients with a well-functioning allograft.


Assuntos
Derivação Arteriovenosa Cirúrgica , Hipertrofia Ventricular Esquerda/fisiopatologia , Nefropatias/terapia , Transplante de Rim , Rim/cirurgia , Diálise Renal , Volume Sistólico , Função Ventricular Esquerda , Remodelação Ventricular , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Tomada de Decisão Clínica , Humanos , Hipertrofia Ventricular Esquerda/etiologia , Rim/fisiopatologia , Nefropatias/complicações , Nefropatias/fisiopatologia , Transplante de Rim/efeitos adversos , Ligadura , Seleção de Pacientes , Recuperação de Função Fisiológica , Fatores de Risco , Resultado do Tratamento
9.
J Magn Reson Imaging ; 47(1): 168-175, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28471511

RESUMO

PURPOSE: To explore the role of whole-volume apparent diffusion coefficient (ADC)-based entropy parameters in the preoperative assessment of gastric cancer's aggressiveness. MATERIALS AND METHODS: In all, 64 patients with gastric cancers who underwent 3.0T magnetic resonance imaging (MRI) were retrospectively included. Regions of interest were drawn manually using in-house software, around gastric cancer lesions on each slice of the diffusion-weighted images and ADC maps. Entropy-related parameters based on ADC maps were calculated automatically: (1) first-order entropy; (2-5) second-order entropies, including entropy(H)0 , entropy(H)45 , entropy(H)90 , and entropy(H)135 ; (6) entropy(H)mean ; and (7) entropy(H)range . Correlations between entropy-related parameters and pathological characteristics were analyzed with the Spearman correlation test. The parameters were compared among different pathological characteristics with independent-samples Kruskal-Wallis or Mann-Whitney U-test. Additionally, diagnostic performances of parameters in differentiating different pathological characteristics were analyzed by receiver operating characteristic (ROC) curve analysis. RESULTS: All the entropy-related parameters significantly correlated with T, N, and overall stages, especially the first-order entropy (r = 0.588, 0.585, and 0.677, respectively, all P < 0.05). All the entropy-related parameters showed significant differences in gastric cancers at different T, N, and overall stages, as well as at different status of vascular invasion (P < 0.001-0.027). And four parameters, including entropy, entropy(H)0 , entropy(H)45 , and entropy(H)90 , showed significant differences between gastric cancers with and without perineural invasion (P 0.006-0.040). CONCLUSION: Entropy-related parameters derived from whole-volume ADC texture analysis could help assess the aggressiveness of gastric cancers via analyzing intratumoral heterogeneity quantitatively, especially the first-order entropy. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:168-175.


Assuntos
Carcinoma/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Interpretação de Imagem Assistida por Computador , Invasividade Neoplásica , Neoplasias Gástricas/diagnóstico por imagem , Adenocarcinoma , Idoso , Algoritmos , Entropia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Curva ROC , Radiologia , Estudos Retrospectivos , Software , Estatísticas não Paramétricas
10.
J Magn Reson Imaging ; 48(2): 349-358, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29297204

RESUMO

BACKGROUND: Since definitive concurrent chemoradiotherapy (CRT) is standard therapy for inoperable esophageal squamous cell carcinoma (ESCC), early evaluation of treatment response is crucial for patients and would be useful in assessing response, especially in patients with severe side effects. PURPOSE: To explore the feasibility of intravoxel incoherent motion (IVIM) MRI in the early assessment of treatment response to CRT. STUDY TYPE: Prospective. POPULATION: Twenty-three inoperable ESCC patients. SEQUENCE: IVIM 3T MRI of nine b values (0, 25, 50, 75, 100, 150, 200, 500 and 800 s/mm2 ) was performed at four timepoints: pre-CRT (within 5 days before CRT), mid-CRT (2-3 weeks after the start of CRT), end-CRT (within 5 days after the end of CRT), and post-CRT (1 month after the end of CRT). ASSESSMENT: IVIM-based parameters and ADC were analyzed independently by two radiologists and treatment response was assessed by the Response Evaluation Criteria in Solid Tumors (RECIST). STATISTICAL TESTS: Analyses of variance for repeated measurements were conducted to observe dynamic changes of IVIM-based parameters (D, f, and D*) and ADC during CRT. The parameters and their change percentages (Δ%) were compared between complete response (CR) and partial response (PR) by Mann-Whitney U-test. Diagnostic performance of parameters in predicting response was tested with receiver-operating characteristic curve analysis. RESULTS: ADC, D, and f increased significantly during CRT (P < 0.001, < 0.001, and 0.001, respectively). ADC, f, Δ%ADC, and Δ%D at mid-CRT in CR group were significantly higher than those in the PR group (P = 0.002, 0.013, 0.005, and 0.011, respectively). D combined with f and ADC had highest area under curve (0.917) in identifying CR from PR. DATA CONCLUSION: IVIM parameters proved useful in assessing response to definitive concurrent CRT for inoperable ESCC and combined with ADC at an early stage of treatment was a good predictor of response. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 4 J. MAGN. RESON. IMAGING 2018;48:349-358.


Assuntos
Quimiorradioterapia , Neoplasias Esofágicas/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Esofágicas/terapia , Carcinoma de Células Escamosas do Esôfago/terapia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Variações Dependentes do Observador , Projetos Piloto , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade
11.
Opt Express ; 25(10): 11606-11621, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28788724

RESUMO

For orthogonal frequency division multiplexing (OFDM) based indoor visible light communication (VLC) systems, partial non-ideal transmission conditions such as insufficient guard intervals and a dispersive channel can result in severe inter-symbol crosstalk (ISC). By deriving from the inverse Fourier transform, we present a novel time domain reshuffling (TDR) concept for both DC-biased optical (DCO-) and asymmetrically clipped optical (ACO-) OFDM VLC systems. By using only simple operations in the frequency domain, potential high peaks can be relocated within each OFDM symbol to alleviate ISC. To simplify the system, we also propose an effective unified design of the TDR schemes for both DCO- and ACO-OFDM. Based on Monte-Carlo simulations, we demonstrate the statistical distribution of the signal high peak values and the complementary cumulative distribution function of the peak-to-average power ratio under different cases for comparison. Simulation results indicate improved bit error rate (BER) performance by adopting TDR to counteract ISC deterioration. For example, for binary phase shift keying at a BER of 10-3, the signal to noise ratio gains are ~1.6 dB and ~6.6 dB for DCO- and ACO-OFDM, respectively, with ISC of 1/64. We also show a reliable transmission by adopting TDR for rectangle 8-quadrature amplitude modulation with ISC of < 1/64.

13.
J Magn Reson Imaging ; 45(2): 440-449, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27367863

RESUMO

PURPOSE: To investigate the efficacy of histogram analysis of the entire tumor volume in apparent diffusion coefficient (ADC) maps for differentiating between histological grades in gastric cancer. MATERIALS AND METHODS: Seventy-eight patients with gastric cancer were enrolled in a retrospective 3.0T magnetic resonance imaging (MRI) study. ADC maps were obtained at two different b values (0 and 1000 sec/mm2 ) for each patient. Tumors were delineated on each slice of the ADC maps, and a histogram for the entire tumor volume was subsequently generated. A series of histogram parameters (eg, skew and kurtosis) were calculated and correlated with the histological grade of the surgical specimen. The diagnostic performance of each parameter for distinguishing poorly from moderately well-differentiated gastric cancers was assessed by using the area under the receiver operating characteristic curve (AUC). RESULTS: There were significant differences in the 5th , 10th , 25th , and 50th percentiles, skew, and kurtosis between poorly and well-differentiated gastric cancers (P < 0.05). There were correlations between the degrees of differentiation and histogram parameters, including the 10th percentile, skew, kurtosis, and max frequency; the correlation coefficients were 0.273, -0.361, -0.339, and -0.370, respectively. Among all the histogram parameters, the max frequency had the largest AUC value, which was 0.675. CONCLUSION: Histogram analysis of the ADC maps on the basis of the entire tumor volume can be useful in differentiating between histological grades for gastric cancer. LEVEL OF EVIDENCE: 4 J. Magn. Reson. Imaging 2017;45:440-449.


Assuntos
Biópsia/métodos , Interpretação Estatística de Dados , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Carga Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Aumento da Imagem/métodos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Eur Radiol ; 27(12): 4951-4959, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28643092

RESUMO

OBJECTIVES: To explore the application of computed tomography (CT) texture analysis in predicting histopathological features of gastric cancers. METHODS: Preoperative contrast-enhanced CT images and postoperative histopathological features of 107 patients (82 men, 25 women) with gastric cancers were retrospectively reviewed. CT texture analysis generated: (1) mean attenuation, (2) standard deviation, (3) max frequency, (4) mode, (5) minimum attenuation, (6) maximum attenuation, (7) the fifth, 10th, 25th, 50th, 75th and 90th percentiles, and (8) entropy. Correlations between CT texture parameters and histopathological features were analysed. RESULTS: Mean attenuation, maximum attenuation, all percentiles and mode derived from portal venous CT images correlated significantly with differentiation degree and Lauren classification of gastric cancers (r, -0.231 ~ -0.324, 0.228 ~ 0.321, respectively). Standard deviation and entropy derived from arterial CT images also correlated significantly with Lauren classification of gastric cancers (r = -0.265, -0.222, respectively). In arterial phase analysis, standard deviation and entropy were significantly lower in gastric cancers with than those without vascular invasion; however, minimum attenuation was significantly higher in gastric cancers with than those without vascular invasion. CONCLUSION: CT texture analysis held great potential in predicting differentiation degree, Lauren classification and vascular invasion status of gastric cancers. KEY POINTS: • CT texture analysis is noninvasive and effective for gastric cancer. • Portal venous CT images correlated significantly with differentiation degree and Lauren classification. • Standard deviation, entropy and minimum attenuation in arterial phase reflect vascular invasion.


Assuntos
Neoplasias Gástricas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Veia Porta/patologia , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Adulto Jovem
16.
Planta Med ; 80(2-3): 201-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24356906

RESUMO

Two new xanthones, 1,8-dihydroxy-3-methoxyxanthone 7-O-[α-L-rhamnopyranosyl(1 → 2)-ß-D-glucopyranoside] (1) and 1,8- dihydroxy-3-methoxyxanthone 7-O-[α-L-rhamnopyranosyl(1 → 3)-α-L-rhamno-pyranosyl (1 → 2)-ß-D-xylopyranoside] (2), together with 26 known xanthones (3-28), were isolated from the aqueous ethanol extract of the traditional Chinese herb Swertia mussotii. Their structures were elucidated via spectroscopic analyses including 2D NMR. The inhibition of α-glucosidase by the isolated xanthones was evaluated by an in vitro high-throughput screening assay. Our results indicated that 1,3,5,8-tetrahydroxyxanthone is the best inhibitor with an IC50 value of 5.33 ± 0.09 µM, while the O-glycosylated xanthones were poor α-glycosidase inhibitors.


Assuntos
Glicosídeo Hidrolases/antagonistas & inibidores , Extratos Vegetais/farmacologia , Swertia/química , Xantonas/farmacologia , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Software , Xantonas/química , Xantonas/isolamento & purificação
17.
Artigo em Inglês | MEDLINE | ID: mdl-38804627

RESUMO

At the end of 2019, the novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became prevalent worldwide, which brought a heavy medical burden and tremendous economic losses to the world population. In addition to the common clinical respiratory symptoms such as fever, cough and headache, patients with COVID-19 often have hematological diseases, especially platelet dysfunction. Platelet dysfunction usually leads to multiple organ dysfunction, which is closely related to patient severity or mortality. In addition, studies have confirmed significant changes in the gene expression profile of circulating platelets under SARS-CoV-2 infection, which will further lead to changes in platelet function. At the same time, studies have shown that platelets may absorb SARS-COV-2 mRNA independently of ACE2, which further emphasizes the importance of the stability of platelet function in defense against SARS-CoV-2 infection. This study reviewed the relationship between COVID-19 and platelet and SARS-CoV-2 damage to the circulatory system, and further analyzed the significantly differentially expressed mRNA in platelets after infection with SARS-CoV-2 on the basis of previous studies. The top eight hub genes were identified as NLRP3, MT-CO1, CD86, ICAM1, MT-CYB, CASP8, CXCL8 and CXCR4. Subsequently, the effects of SARS-CoV-2 infection on platelet transcript abnormalities and platelet dysfunction were further explored on the basis of 8 hub genes. Finally, the treatment measures of complications caused by platelet dysfunction in patients with COVID-19 were discussed in detail, so as to provide reference for the prevention, diagnosis and treatment of COVID-19.

18.
Front Cardiovasc Med ; 11: 1383567, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38720919

RESUMO

Background: Patients with obstructive sleep apnea hypopnea syndrome (OSAHS) combined with resistant hypertension (RH) have a high risk of developing primary aldosteronism (PA). This study investigated the aldosterone-renin ratio (ARR), plasma aldosterone concentration (PAC), and plasma renin activity (PRA) to determine the optimal cutoff values for PA diagnosis in patients with OSAHS combined with RH. Methods: Patients diagnosed with moderate and severe OSAHS combined with RH were recruited from the inpatient clinic of the Department of Endocrinology at Ji'an Central Hospital between October 2020 and April 2023. The included patients were divided into PA and no-PA groups. Diagnostic accuracy measures were calculated for each group, and receiver operating characteristic (ROC) curves were generated. Results: A total of 241 patients were included, of which 103 had positive ARR screening results in the diagnostic accuracy analysis and 66 were diagnosed with PA. PAC and ARR showed moderate predictive capacity for PA, with area under the curve (AUC) values of 0.66 [95% confidence interval (CI): 0.55-0.77] and 0.72 (95% CI: 0.63-0.82), respectively, while PRA exhibited a limited predictive capacity (AUC = 0.51, 95% CI: 0.40-0.63). Using 45 as the optimal cutoff value for ARR, the sensitivity was 86% and the specificity was 52%. The optimal cutoff value for PAC was 17, with a sensitivity of 78% and a specificity of 55%. Notably, in patients with severe OSAHS, ARR at screening demonstrated significant predictive value for PA, with an AUC of 0.84 (95% CI: 0.72-0.96), a sensitivity of 85%, and a specificity of 76%. Conversely, in patients with moderate OSAHS, only ARR demonstrated significant predictive value for PA diagnosis, while PAC did not demonstrate notable diagnostic value. Conclusion: ARR and PAC are initial screening tools for PA, facilitating early detection, particularly in low-resource settings. In patients with OSAHS and RH, the ARR and PAC thresholds for PA diagnosis may require more stringent adjustment.

19.
Medicine (Baltimore) ; 102(40): e35424, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37800831

RESUMO

Compared with young patients, elderly patients with gastric cancer usually have lower muscle mass, poorer nutritional status, lower immunity, and worse cardiopulmonary function. Therefore, how to improve the prognosis of elderly gastric cancer patients after laparoscopic-assisted radical gastrectomy is the focus and difficulty of clinician. The aim of our study was to investigate the risk factors for postoperative complications of these patients. The data of gastric cancer patients aged ≥ 60 years who underwent laparoscopic-assisted radical gastrectomy were analyzed. Univariate was used to determine the potential risk factors and then multivariate analyses was used to determine the independent risk factors for postoperative complications. Univariate analysis showed that age, preoperative red blood cell (RBC), preoperative albumin (ALB), preoperative C-reactive protein (CRP), preoperative hemoglobin (Hb), preoperative blood transfusion, preoperative lymphocytes, total cholesterol, CRP-to-ALB ratio, controlling nutritional status (CONUT) score, TNM stage were all the potential risk factors for postoperative complications. Binary logistic regression showed that CONUT, age and preoperative RBC were correlated with postoperative complications. For elderly gastric cancer patients after laparoscopic-assisted radical gastrectomy, CONUT, age and preoperative RBC were all the independent risk factors for overall postoperative complications and could be used as reliable indicators for judging the short-term prognosis.


Assuntos
Laparoscopia , Neoplasias Gástricas , Idoso , Humanos , Neoplasias Gástricas/complicações , Prognóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Albuminas , Gastrectomia/efeitos adversos , Laparoscopia/efeitos adversos , Proteína C-Reativa , Estudos Retrospectivos
20.
Comput Biol Med ; 165: 107410, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37672928

RESUMO

COVID-19 has a high rate of infection in dialysis patients and poses a serious risk to human health. Currently, there are no dialysis centers in China that have analyzed the prevalence of COVID-19 infection in dialysis patients and the mortality rate. Although machine learning-based disease prediction methods have proven to be effective, redundant attributes in the data and the interpretability of the predictive models are still worth investigating. Therefore, this paper proposed a wrapper feature selection classification model to achieve the prediction of the risk of COVID-19 infection in dialysis patients. The method was used to optimize the feature set of the sample through an enhanced JAYA optimization algorithm based on the dispersed foraging strategy and the greedy levy mutation strategy. Then, the proposed method combines fuzzy K-nearest neighbor for classification prediction. IEEE CEC2014 benchmark function experiments as well as prediction experiments on the uremia dataset are used to validate the proposed model. The experimental results showed that the proposed method has a high prediction accuracy of 95.61% for the prevalence risk of COVID-19 infection in dialysis patients. Furthermore, it was shown that proalbumin, CRP, direct bilirubin, hemoglobin, albumin, and phosphorus are of great value for clinical diagnosis. Therefore, the proposed method can be considered as a promising method.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , Diálise Renal , Algoritmos , Hospitalização , Aprendizado de Máquina
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