Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 47
Filtrar
1.
Hepatology ; 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34717002

RESUMO

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is a key component of metabolic syndrome ranging from nonalcoholic fatty liver (NAFL) to nonalcoholic steatohepatitis (NASH) and is now becoming the leading cause of cirrhosis and hepatocellular carcinoma worldwide. However, due to the complex and unclear pathophysiological mechanism, there are no specific approved agents for treating NASH. Breviscapine, a natural flavonoid prescription drug isolated from the traditional Chinese herb Erigeron breviscapus, exhibits a wide range of pharmacological properties, including effects on metabolism. However, the anti-NASH efficacy and mechanisms of breviscapine have not yet been characterized. APPROACH & RESULTS: We evaluated the effects of breviscapine on the development of hepatic steatosis, inflammation and fibrosis in vivo and in vitro under metabolic stress. Breviscapine treatment significantly reduced lipid accumulation, inflammatory cell infiltration, liver injury and fibrosis in mice fed a high-fat diet (HFD), a high-fat/high-cholesterol (HFHC) diet, or a methionine- and choline-deficient (MCD) diet. In addition, breviscapine attenuated lipid accumulation, inflammation and lipotoxicity in hepatocytes undergoing metabolic stress. RNA sequencing and multiomics analyses further indicated that the key mechanism linking the anti-NASH effects of breviscapine was inhibition of TAK1 phosphorylation and the subsequent MAPK signaling cascade. Treatment with the TAK1 inhibitor 5Z-7-oxozeaenol abrogated breviscapine-mediated hepatoprotection under metabolic stress. Molecular docking illustrated that breviscapine directly bound to TAK1. CONCLUSION: Breviscapine prevents metabolic stress-induced NASH progression through direct inhibition of TAK1 signaling. Breviscapine might be a novel therapeutic candidate for the treatment of NASH.

2.
Hepatology ; 2021 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-34482560

RESUMO

BACKGROUND AND AIMS: Nonalcoholic steatohepatitis (NASH) is a complicated disease characterized by hepatocyte steatosis, inflammation infiltration, and liver fibrosis. Accumulating evidence suggests that the innate immunity plays a key role in NASH progression. Here, we aimed to reveal the role of melanoma-differentiation-associated gene 5 (MDA5, also known as Ifih1), a conventional innate immune regulator upon viral infection, in the progression of NASH and investigate its underlying mechanism. APPROACH AND RESULTS: We first examined the expression of MDA5 and found that MDA5 was markedly downregulated in the livers with NASH in human individuals and mice models. MDA5 overexpression significantly inhibited the free fatty acid (FFA) induced lipid accumulation and inflammation in hepatocyte in vitro, while MDA5 knockdown promotes hepatocyte lipotoxicity. Using hepatocyte-specific Mda5 gene knockout and transgenic mice, we found that diet induced hepatic steatosis, inflammation and liver fibrosis were markedly exacerbated by Mda5 deficiency but suppressed by Mda5 overexpression. Mechanistically, we found that the activation of ASK1-MAPK pathway was significantly inhibited by MDA5 but enhanced by MDA5 deletion. We further validated that MDA5 directly interacted with ASK1 and suppressed its N-terminal dimerization. Importantly, blockage of ASK1 with adenovirus expressing dominant negative ASK1 (dnASK1) obviously reversed the lipid accumulation and ASK1 pathway activation when Mda5 knockout. CONCLUSIONS: These data indicate that MDA5 is an essential suppressor in NASH, the findings support MDA5 as a novel regulator of ASK1 and a promising therapeutic target for NASH.

3.
Hepatology ; 74(6): 3018-3036, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34272738

RESUMO

BACKGROUND AND AIMS: NAFLD is the most prevalent chronic liver disease worldwide, but no effective pharmacological therapeutics are available for clinical use. NASH is the more severe stage of NAFLD. During this progress, dysregulation of endoplasmic reticulum (ER)-related pathways and proteins is one of the predominant hallmarks. We aimed to reveal the role of ring finger protein 5 (RNF5), an ER-localized E3 ubiquitin-protein ligase, in NASH and to explore its underlying mechanism. APPROACH AND RESULTS: We first inspected the expression level of RNF5 and found that it was markedly decreased in livers with NASH in multiple species including humans. We then introduced adenoviruses for Rnf5 overexpression or knockdown into primary mouse hepatocytes and found that palmitic acid/oleic acid (PAOA)-induced lipid accumulation and inflammation in hepatocytes were markedly attenuated by Rnf5 overexpression but exacerbated by Rnf5 gene silencing. Hepatocyte-specific Rnf5 knockout significantly exacerbated hepatic steatosis, inflammatory response, and fibrosis in mice challenged with diet-induced NASH. Mechanistically, we identified 3-hydroxy-3-methylglutaryl CoA reductase degradation protein 1 (HRD1) as a binding partner of RNF5 by systematic interactomics analysis. RNF5 directly bound to HRD1 and promoted its lysine 48 (K48)-linked and K33-linked ubiquitination and subsequent proteasomal degradation. Furthermore, Hrd1 overexpression significantly exacerbated PAOA-induced lipid accumulation and inflammation, and short hairpin RNA-mediated Hrd1 knockdown exerted the opposite effects. Notably, Hrd1 knockdown significantly diminished PAOA-induced lipid deposition, and up-regulation of related genes resulted from Rnf5 ablation in hepatocytes. CONCLUSIONS: These data indicate that RNF5 inhibits NASH progression by targeting HRD1 in the ubiquitin-mediated proteasomal pathway. Targeting the RNF5-HRD1 axis may provide insights into the pathogenesis of NASH and pave the way for developing strategies for NASH prevention and treatment.

4.
Hepatology ; 74(6): 3074-3090, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34297426

RESUMO

BACKGROUND AND AIMS: NASH is currently one of the most common causes of liver transplantation and hepatocellular carcinoma. Thus far, there is still no effective pharmacological therapy for this disease. Recently, Gastrodin has demonstrated hepatoprotective effects in a variety of liver diseases. The aim of this study is to investigate the function of Gastrodin in NASH. APPROACH AND RESULTS: In our study, Gastrodin showed potent therapeutic effects on NASH both in vivo and in vitro. In high-fat diet or high-fat and high-cholesterol diet-fed mice, the liver weight, hepatic and serum triglyceride and cholesterol contents, and serum alanine aminotransferase and aspartate aminotransferase activity levels were markedly reduced by Gastrodin treatment as compared with the corresponding vehicle groups. Notably, Gastrodin showed minimal effects on the function and histological characteristics of other major organs in mice. We further examined the effects of Gastrodin on lipid accumulation in primary mouse hepatocytes and human hepatocyte cell line and observed that Gastrodin showed a significant decrease in lipid accumulation and inflammatory response in hepatocytes under metabolic stress. Furthermore, RNA-sequencing analysis systemically indicated that Gastrodin suppressed the pathway and key regulators related to lipid accumulation, inflammation, and fibrosis in the pathogenesis of NASH. Mechanistically, we found that Gastrodin protected against NASH by activating the adenosine monophosphate-activated protein kinase (AMPK) pathway, which was supported by the result that the AMPK inhibitor Compound C or AMPK knockdown blocked the Gastrodin-mediated hepatoprotective effect. CONCLUSIONS: Gastrodin attenuates steatohepatitis by activating the AMPK pathway and represents a therapeutic for the treatment of NASH.

5.
Hepatology ; 74(6): 3091-3109, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34320238

RESUMO

BACKGROUND AND AIMS: NAFLD has become a tremendous burden for public health; however, there is no drug for NAFLD therapy at present. Impaired endo-lysosome-mediated protein degradation is observed in a variety of metabolic disorders, such as atherosclerosis, type 2 diabetes mellitus, and NAFLD. Small integral membrane protein of lysosome/late endosome (SIMPLE) is a regulator of endosome-to-lysosome trafficking and cell signaling, but the role that SIMPLE plays in NAFLD progression remains unknown. Here we investigated SIMPLE function in NAFLD development and sophisticated mechanism therein. APPROACH AND RESULTS: This study found that in vitro knockdown of SIMPLE significantly aggravated lipid accumulation and inflammation in hepatocytes treated with metabolic stimulation. Consistently, in vivo experiments showed that liver-specific Simple-knockout (Simple-HKO) mice exhibited more severe high-fat diet (HFD)-induced, high-fat-high-cholesterol diet (HFHC)-induced, and methionine-choline-deficient diet (MCD)-induced steatosis, glucose intolerance, inflammation, and fibrosis than those fed with normal chow (NC) diet. Meanwhile, RNA-sequencing demonstrated the up-regulated signaling pathways and signature genes involved in lipid metabolism, inflammation, and fibrosis in Simple-HKO mice compared with control mice under metabolic stress. Mechanically, we found SIMPLE directly interact with epidermal growth factor receptor (EGFR). SIMPLE deficiency results in dysregulated degradation of EGFR, subsequently hyperactivated EGFR phosphorylation, thus exaggerating NAFLD development. Moreover, we demonstrated that using EGFR inhibitor or silencing EGFR expression could ameliorate lipid accumulation induced by the knockdown of SIMPLE. CONCLUSIONS: SIMPLE ameliorated NASH by prompting EGFR degradation and can be a potential therapeutic candidate for NASH.

6.
J Org Chem ; 86(11): 7625-7635, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33993694

RESUMO

We have developed a methodology for the greatly efficient construction of significant 2,3-dihydrobenzofuran scaffolds bearing a quaternary carbon center at the C2 position by means of [4 + 1] annulation reactions between p-quinone methides and α-aryl diazoacetates as C1 synthons through organocatalysis by readily accessible TfOH catalyst under mild and transition metal-free conditions. This metal-free protocol furnishes an operationally simple and swift process for the free assembly of diverse highly functionalized 2,3-dihydrobenzofurans and also features broad substrate scope, excellent functional group compatibility, and environmental friendliness. Mechanistic investigation suggested that the reaction undergoes a rapid cascade protonation/intermolecular Michael addition/intramolecular substitution process.


Assuntos
Benzofuranos , Indolquinonas , Catálise
7.
Zhongguo Zhen Jiu ; 41(4): 435-8, 2021 Apr 12.
Artigo em Chinês | MEDLINE | ID: mdl-33909367

RESUMO

To explore the problems and countermeasures existing in acupuncture and moxibustion clinical studies, in the perspective of the key steps of Guideline for Clinical Practice of Acupuncture and Moxibustion: Insomnia. The problems include: confusion of disease names and disunity of diagnostic criteria, inadequate refined clinical problems that need to be addressed, lack of targeted analysis of efficacy evaluation index, lack of adequate research on common acupuncture, difficulty to balance innovation and universality, lack of emphasis on the importance of timing for acupuncture, lack of attention to healthy lifestyles and self-care. We suggests that the disease name and diagnostic criteria should refer to the authoritative standards; the clinical study design should based on the realistic clinical problems; the efficacy evaluation index should based on the clinical needs and be analyzed targetedly; further research on common acupuncture or therapy should be carried out.


Assuntos
Terapia por Acupuntura , Acupuntura , Moxibustão , Distúrbios do Início e da Manutenção do Sono , Humanos , Padrões de Referência , Distúrbios do Início e da Manutenção do Sono/terapia
8.
ACS Med Chem Lett ; 12(3): 397-403, 2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33738067

RESUMO

SIRT1, a member of the sirtuin family, catalyzes the deacetylation of proteins with the transformation of NAD+ into nicotinamide and 2'-O-acetyl-ADP-ribose. Selective SIRT1/2 inhibitors have potential application in the chemotherapy of colorectal carcinoma, prostate cancer, and myelogenous leukemia. Here we identified novel SIRT1 inhibitors with the scaffold of 5-benzylidene-2-phenyl-1,3-dioxane-4,6-dione. The most potent inhibitor 12n displayed an IC50 of 460 nM and a selectivity for SIRT1 over SIRT2, SIRT3, and SIRT5 of 113.5-, 254.3-, and 10.83-fold, respectively. It did not affect the activity of SIRT6. To elucidate the inhibitory mechanism, we determined the inhibition type of the inhibitor by enzyme kinetic analysis, showing that the inhibitor was competitive to the acetyl peptide and noncompetitive to NAD+. Further, the interaction of the inhibitor in SIRT1 was studied by using molecular docking, which was validated by the structure-activity relationship analysis of the inhibitors and the site-directed mutagenesis of SIRT1. Consistent with the in vitro assays, the inhibitors increased the acetylation level of p53 in a concentration-dependent manner in cells.

9.
World J Clin Cases ; 9(4): 864-870, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33585633

RESUMO

BACKGROUND: Treatment for neck lymph node metastases after adequate initial surgery in medullary thyroid carcinoma (MTC) has been controversial. Ultrasound (US)-guided radiofrequency ablation (RFA) has been widely used in recurrent well-differentiated thyroid carcinoma. Here, we report for the first time the use of RFA in a patient with recurrent MTC. CASE SUMMARY: We report the case of a 56-year-old woman with cervical lymph node metastases of MTC. Four years previously, she had undergone a total thyroidectomy and neck lymph node dissection. A neck US revealed many enlarged nodes during the follow-up period. Moreover, the serum calcitonin jumped to 198.17 pg/mL, which strongly indicated the recurrence of MTC. Subsequently, two metastatic lymph nodes were confirmed by US-guided fine-needle aspiration-cytology and fine-needle aspiration-calcitonin, and then the patient was treated with RFA. Four months later, the neck US and a contrast-enhanced US showed obvious shrinkage in the ablation zones, and the serum calcitonin dropped to 11.80 pg/mL. CONCLUSION: This case suggests that RFA may be an effective and safe treatment for local recurrent MTC.

10.
Nano Lett ; 21(4): 1792-1799, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33570422

RESUMO

Recently, multidimensional metasurfaces, which can modulate multiple optical parameters of input and output lights simultaneously, have aroused intensive interest. Here, we demonstrate multidimensional switchable images and 3D integrated beam splitters based on hyperbolic metamaterials (HMMs). On one hand, a switchable image controlled by output helicity and input wavelengths is achieved by arranging HMMs with different polarization conversion performance. On the other hand, polarization-multiplexed broadband beam splitter is generated by spatially engineering the subunit with broadband half-plate performance. By integrating the multiplexed beam splitter with a filter metamaterial, this multidimensional beam splitter can further realize the separation of output light by space and wavelength. This cascaded multilayer metamaterial achieves a brand new optical functionality and offers more inspiring possibilities for the design of multifunctional optical devices in the future.

11.
Hepatology ; 74(2): 686-703, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33576035

RESUMO

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease, especially nonalcoholic steatohepatitis (NASH), has become a major cause of liver transplantation and liver-associated death. NASH is the hepatic manifestation of metabolic syndrome and is characterized by hepatic steatosis, inflammation, hepatocellular injury, and different degrees of fibrosis. However, there is no US Food and Drug Administration-approved medication to treat this devastating disease. Therapeutic activators of the AMP-activated protein kinase (AMPK) have been proposed as a potential treatment for metabolic diseases such as NASH. Cordycepin, a natural product isolated from the traditional Chinese medicine Cordyceps militaris, has recently emerged as a promising drug candidate for metabolic diseases. APPROACH AND RESULTS: We evaluated the effects of cordycepin on lipid storage in hepatocytes, inflammation, and fibrosis development in mice with NASH. Cordycepin attenuated lipid accumulation, inflammation, and lipotoxicity in hepatocytes subjected to metabolic stress. In addition, cordycepin treatment significantly and dose-dependently decreased the elevated levels of serum aminotransferases in mice with diet-induced NASH. Furthermore, cordycepin treatment significantly reduced hepatic triglyceride accumulation, inflammatory cell infiltration, and hepatic fibrosis in mice. In vitro and in vivo mechanistic studies revealed that a key mechanism linking the protective effects of cordycepin were AMPK phosphorylation-dependent, as indicated by the finding that treatment with the AMPK inhibitor Compound C abrogated cordycepin-induced hepatoprotection in hepatocytes and mice with NASH. CONCLUSION: Cordycepin exerts significant protective effects against hepatic steatosis, inflammation, liver injury, and fibrosis in mice under metabolic stress through activation of the AMPK signaling pathway. Cordycepin might be an AMPK activator that can be used for the treatment of NASH.

12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(1): 149-152, 2021 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-33474905

RESUMO

Objective: This study investigated the clinicopathological traits and ultrasound features of female reproductive system extraosseous Ewing's sarcoma (EES) and explored the diagnostic value of ultrasonography for this condition. Methods: Cases of female pelvic EES diagnosed and treated at our hospital between June 2009 and June 2019 were included in this study. Pathology data and ultrasound manifestations were assessed retrospectively to summarize the clinical traits and ultrasound features of female reproductive system EES. Based on the results, recommendations for the ultrasonography-based diagnosis of this disease were proposed. Results: During the 10-year study period, 13 female patients were diagnosed with EES in the pelvic cavity based on the results of postoperative pathology tests. The age of the patients ranged from 8 mouth to 40 years, and no patients demonstrated specific clinical symptoms. However, an examination of tumor biomarkers revealed that certain patients had elevated levels of CA125. In the 13 patients, 19 lesions were identified, including 16 that involved the reproductive system. The primary ultrasound manifestation was uneven, low-echo solidity or cystic solidity, exhibiting large size, irregular shape, and unclear boundary. A few patients had concurrent ascites. Although some lesions lacked blood supply, the blood supply of most lesions was medium to abundant, and the blood flow was mostly characterized by low resistant. Almost none of the lesions were definitively diagnosed preoperatively. Conclusions: Preoperative definitive diagnosis of EES in the female reproductive system remains a great clinical challenge. Although certain clinical traits and ultrasound features are associated with this disease, and color Doppler ultrasonography might provide vital information indicating the presence of EES, the final diagnosis still depends on the pathological test results of the patients.


Assuntos
Sarcoma de Ewing , Criança , Feminino , Genitália Feminina , Humanos , Estudos Retrospectivos , Sarcoma de Ewing/diagnóstico por imagem , Ultrassonografia , Ultrassonografia Doppler em Cores
13.
J Psychiatr Res ; 135: 28-36, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33445058

RESUMO

The relationship between maternal infection exposure and the risk of psychosis in the offspring is inconsistent. We systematically assessed this relationship. Unrestricted searches of the PubMed and Embase databases were conducted, with an end date of February 1, 2020, to identify relevant studies that met predetermined inclusion criteria. Random-effects models were adopted to estimate the overall relative risk. Twenty-three observational studies were included in the analysis. The results showed that mothers who had a history of infection during pregnancy experienced a significantly increased risk of developing psychosis in offspring (OR = 1.25, 95% confidence interval (CI): 1.1-1.41; P = 0.001). Sensitivity and subgroup analyses yielded consistent results. For specific pathogens, the risk of developing psychosis in offspring was increased among mothers with herpes simplex virus 2 (HSV-2) exposure (OR, 1.32; 95% CI, 1.09-1.6; P = 0.004). However, other maternal-specific pathogen exposures were not significantly associated with the risk of psychosis in offspring. No evidence of publication bias was observed. Although evidence of heterogeneity should be carefully evaluated, our findings suggest that maternal infection exposure may be associated with a greater risk of psychosis in the offspring.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Transtornos Psicóticos , Feminino , Humanos , Exposição Materna/efeitos adversos , Mães , Gravidez , Efeitos Tardios da Exposição Pré-Natal/epidemiologia , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/etiologia , Fatores de Risco
14.
J Org Chem ; 86(4): 3223-3231, 2021 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-33378204

RESUMO

A time-economical TfOH-catalyzed N-H insertion between anilines and α-alkyl and α-aryl-α-diazoacetates provides a straightforward approach to access unnatural α-amino esters, which readily undergo various transformations and can thus be used for the synthesis of pharmaceutically relevant molecules. The α-amino esters were obtained in moderate to excellent yields.


Assuntos
Compostos de Anilina , Ésteres , Catálise , Estereoisomerismo
15.
J Org Chem ; 85(23): 14916-14925, 2020 12 04.
Artigo em Inglês | MEDLINE | ID: mdl-32957783

RESUMO

Aryl benzofuranones are privileged structural units present in natural products and pharmaceutically relevant compounds with high bioactivity and therapeutic value; synthetic access to these scaffolds remains an area of intensive interest. A new and efficient TfOH-catalyzed cascade ortho C-H activation/lactonization of phenols with α-aryl-α-diazoacetates is reported. This metal-free protocol provides an operationally simple and rapid method for the one-pot assembly of diverse α-aryl benzofuranones in high yields with broad substrate scope, a readily starting material, good chemo-regioselectivity, and excellent functional group compatibility.

16.
Int J Infect Dis ; 100: 34-41, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32798659

RESUMO

BACKGROUND: The incidence of venous thromboembolic events (VTE) in patients with COVID-19 is generally high but varies markedly. However, the relationship between anticoagulation and mortality in patients with COVID-19 is still unclear. METHODS: We performed a systematic review and meta-analysis to determine the incidence of VTE and evaluate the role of anticoagulation in patients with COVID-19. Random effects models were used to determine overall pooled estimates and 95% confidence intervals (CIs). RESULTS: After a database search, 25 observational studies (20 on VTE incidence and 5 on the relationship between anticoagulation and mortality) were included. The pooled incidence rates of VTE, pulmonary embolism (PE), and deep vein thrombosis (DVT) in hospitalised COVID-19 patients were 21% (95% CI 15-27%), 15% (95% CI 10-20%), and 27% (95% CI 19-36%), respectively. A meta-analysis of five studies found that anticoagulation was not associated with an increased risk of mortality in hospitalised COVID-19 patients (RR = 0.86, 95% CI, 0.69-1.09, P = 0.218; I2 = 47.4%). CONCLUSIONS: In conclusion, the incidence of VTE among hospitalised COVID-19 patients was high. Clinical trials are urgently needed to evaluate the roles of prophylactic and therapeutic anticoagulation in COVID-19.


Assuntos
Anticoagulantes/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/complicações , Pneumonia Viral/complicações , Tromboembolia Venosa/epidemiologia , COVID-19 , Infecções por Coronavirus/mortalidade , Humanos , Incidência , Pandemias , Pneumonia Viral/mortalidade , SARS-CoV-2 , Tromboembolia Venosa/prevenção & controle
17.
Medicine (Baltimore) ; 99(34): e21341, 2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32846755

RESUMO

This study investigated the clinicopathological traits and ultrasound features (including 2-dimensional and color Doppler ultrasound) of female genital system malignant lymphomas and explored the diagnostic performance of ultrasonography in this disease.Cases of female pelvic lymphoma diagnosed and treated at our hospital between July 2009 and July 2019 were included in this study. Pathological data and ultrasonic manifestations were assessed retrospectively to summarize the clinical traits and ultrasonic features of female genital system lymphoma (FGSL). Based on the results, recommendations for ultrasonography-based diagnosis of this disease are proposed.During the 10-year study period, 20 female patients were diagnosed with malignant lymphomas in the pelvic cavity based on postoperative pathology tests. The age of the patients ranged from 11 to 83 years, and no patients demonstrated specific clinical traits; however, examination of tumor biomarkers revealed that certain patients had elevated levels of CA125. Twenty-eight lesions were identified in the 20 patients, including 24 involving the reproductive system. The primary ultrasonic manifestations were hypoechoic or extremely hypoechoic solid lesions that were relatively large in size, had a relatively regular shape, and had clear boundaries. Certain patients had concurrent ascites, and although some lesions lacked blood supply, most lesions had medium to abundant blood flow, which was largely characterized by low resistance. Almost none of the lesions were definitively diagnosed preoperatively.Diagnosing malignant lymphomas in the female genital tract remains a considerable clinical challenge. Although certain clinical traits and ultrasonic features are associated with this disease and color Doppler ultrasonography might provide vital information indicating the presence of lymphoma, the final diagnosis depends on the clinical and pathological test results of the patients.


Assuntos
Neoplasias dos Genitais Femininos/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia Doppler em Cores
18.
Nanoscale ; 12(18): 10065-10071, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32347878

RESUMO

The realization of tunable metasurfaces is of fundamental importance for boosting the electromagnetic field control ability. Especially, it is important to put forward new modulation methods to further understand their underlying modulation mechanism and expand their application range. In this paper, tunable electromagnetically induced transparency (EIT) metasurfaces based on the phase change material Ge2Sb2Te5 (GST) are proposed and experimentally demonstrated. Different from previous modulation methods of directly introducing the GST film below the metasurfaces, here a two-step lithography method is introduced to combine independent GST strips with bright and dark meta-atoms in the EIT structures, respectively, achieving the independent modulation of the EIT-like spectra. In addition, by applying temporal coupled-mode theory (TCMT), the EIT-like spectra with different GST crystallization levels were analysed and the corresponding characteristic parameters were determined simultaneously. These fitting results reveal that GST strips can modulate the resonances of the bright and dark meta-atoms independently by shifting the resonant frequency and increasing the decay rate, which in turn result in the different modulation features of the EIT-like spectra. This method improves the degree of freedom of active modulation and provides a new route for tunable slow light devices.

19.
Nat Prod Res ; 34(12): 1728-1734, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30450968

RESUMO

A novel lactone-type norcucurbitacin, designated as neocucurbitacin D (1), together with five known cucurbitane triterpenes were isolated from traditional Tibetan medicine "Se Ji Mei Duo", which is the seed of Herpetospermum pedunculosum (Ser.) C.B. Clarke. The structure of neocucurbitacin D was elucidated by spectroscopic analysis, including 2D NMR and X-ray techniques. Compounds 1-6 were screened for their xanthine oxidase (XOD) inhibitory activity. Compound 1, 2 and 4 exhibited significant XOD inhibition with IC50 values ranging from 10.16 to 18.41 µM. The absolute stereochemistry and XOD inhibitiory activity of lactone-type norcucurbitacins was reported firstly.


Assuntos
Cucurbitaceae/química , Inibidores Enzimáticos/isolamento & purificação , Triterpenos/farmacologia , Xantina Oxidase/antagonistas & inibidores , Cucurbitacinas , Inibidores Enzimáticos/farmacologia , Glicosídeos , Humanos , Concentração Inibidora 50 , Lactonas/química , Lactonas/isolamento & purificação , Lactonas/farmacologia , Conformação Molecular , Sementes/química , Triterpenos/isolamento & purificação
20.
J Org Chem ; 85(6): 4011-4018, 2020 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-31829579

RESUMO

An organocatalytic asymmetric enantioselective domino oxa-Michael-Mannich-[1,3]-amino rearrangement reaction of N-tosylsalicylimines with a wide range of α,ß-unsaturated aldehydes utilizing diarylprolinol silyl ether catalysis is described. The catalytic reactions proceed with excellent enantioselectivity (up to 99% ee) to produce the corresponding chair N-tosylimines-chromenes with a yield of up to 99%, tolerating a range of functional groups. This methodology offers a new method with great potential to further extend the synthetic power and versatility of chiral aminocatalysis.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...