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1.
Ann Med Surg (Lond) ; 86(5): 3117-3122, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38694365

RESUMO

Introduction: Appendiceal signet-ring cell adenocarcinoma (ASCA) is rare and more aggressive in malignant appendiceal neoplasms. The presentation can be appendicitis, which is lack of specific symptom and makes early diagnosis difficult. There is no effective surveillance. Prognosis largely relies on timely detection. We report a case of ASCA incidentally diagnosed through pathological examination after appendectomy for appendicitis. Case presentation: The patient presented to our department with a progressive right lower quadrant abdominal pain lasting for 3 days. Physical examination revealed rigidity, tenderness, and rebound tenderness on the right lower quadrant. A computed tomography scan showed a thickened, inflamed appendix with peri-appendiceal fat stranding without noticeable appendiceal mass at initial evaluation. The diagnosis was considered acute appendicitis, and an appendectomy was performed. The appendix was inflamed, gangrenous and perforated, and no mass was found during the surgery. Surgical specimen was sent for physiological examination, which incidentally detected signet-ring cell in H&E staining. And immunohistochemistry confirmed the diagnosis of ASCA with small amount of neuroendocrine neoplasms. Conclusion: Early diagnosis of ASCA can incidentally be made on pathological specimen following appendectomy for appendicitis. A routine pathological examination should be emphasized, and appendectomy may not be the endpoint of the treatment. Hemicolectomy and adjuvant therapy might ensue upon the diagnosis of appendiceal neoplasm. The poor prognosis of ASCA makes a timely diagnosis significant. Basic research is promising to unravel the molecular mechanisms of pathogenesis, finding typical tumor markers for screening and novel effective therapies for advanced cases.

2.
Ann Med Surg (Lond) ; 86(2): 1152-1155, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38333290

RESUMO

Introduction and importance: Abdominal cocoon syndrome (ACS), as a rare cause of mechanical intestinal obstruction, can be divided into primary/idiopathic vs. secondary type. The primary ACS is often asymptomatic and only diagnosed in exploratory laparotomy. The major treatment of surgery can be challenging. Since the gut wall and peritoneum are densely adhered, gut perforation might occur during adhesiolysis. Thus, it is important to have an experienced surgeon to perform the surgery. Case presentation: The authors present a primary ACS case of a 50-year-old man. The patient demonstrated an unbearable upper abdominal pain upon admission. A computed tomography (CT) scan showed a severe bowel obstruction. An exploratory laparotomy was indicated, leading to the diagnosis of ACS, which was considered idiopathic after ruling out secondary factors. An adhesiolysis was performed successfully. Note that the entire intestine measured was only 2.1 m during the surgery. There was no post-surgical complication. The patient was recovered uneventfully. Clinical discussion: The aetiology of primary ACS is unknown. The incidence is comparatively low and considered equal between men and women. As a rare cause of gut obstruction, the suspicion of the diagnosis should be strengthened. Surgery including adhesiolysis and bowel resection remains the major treatment. If adhesiolysis fails, bowel resection will be inevitable. The knowledge and experience of surgeon will be tested. Conclusion: The aetiology of primary ACS should be further explored. And the differential diagnosis of bowel obstruction should cover ACS in order for the surgeon to be prepared before surgery.

3.
Adv Sci (Weinh) ; 11(13): e2306248, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38251411

RESUMO

Protein degradation techniques, such as proteolysis-targeting chimeras (PROTACs) and lysosome-targeting chimeras (LYTACs), have emerged as promising therapeutic strategies for the treatment of diseases. However, the efficacy of current protein degradation methods still needs to be improved to address the complex mechanisms underlying diseases. Herein, a LYTAC Plus hydrogel engineered is proposed by nucleic acid self-assembly, which integrates a gene silencing motif into a LYTAC construct to enhance its therapeutic potential. As a proof-of-concept study, vascular endothelial growth factor receptor (VEGFR)-binding peptides and mannose-6 phosphate (M6P) moieties into a self-assembled nucleic acid hydrogel are introduced, enabling its LYTAC capability. Small interference RNAs (siRNAs) is then employed that target the angiopoietin-2 (ANG-2) gene as cross-linkers for hydrogel formation, giving the final LYTAC Plus hydrogel gene silencing ability. With dual functionalities, the LYTAC Plus hydrogel demonstrated effectiveness in simultaneously reducing the levels of VEGFR-2 and ANG-2 both in vitro and in vivo, as well as in improving therapeutic outcomes in treating neovascular age-related macular degeneration in a mouse model. As a general material platform, the LYTAC Plus hydrogel may possess great potential for the treatment of various diseases and warrant further investigation.


Assuntos
Ácidos Nucleicos , Fator A de Crescimento do Endotélio Vascular , Camundongos , Animais , Fator A de Crescimento do Endotélio Vascular/genética , Regulação para Baixo , RNA Interferente Pequeno/genética , Hidrogéis
4.
Angew Chem Int Ed Engl ; 63(4): e202315282, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38032360

RESUMO

Recently, therapeutic cancer vaccines have emerged as promising candidates for cancer immunotherapy. Nevertheless, their efficacies are frequently impeded by challenges including inadequate antigen encapsulation, insufficient immune activation, and immunosuppressive tumor microenvironment. Herein, we report a three-in-one hydrogel assembled by nucleic acids (NAs) that can serve as a vaccine to in situ trigger strong immune response against cancer. Through site-specifically grafting the chemodrug, 7-ethyl-10-hydroxycamptothecin (also known as SN38), onto three component phosphorothioate (PS) DNA strands, a Y-shaped motif (Y-motif) with sticky ends is self-assembled, at one terminus of which an unmethylated cytosine-phosphate-guanine (CpG) segment is introduced as an immune agonist. Thereafter, programmed cell death ligand-1 (PD-L1) siRNA that performs as immune checkpoint inhibitor is designed as a crosslinker to assemble with the CpG- and SN38-containing Y-motif, resulting in the formation of final NA hydrogel vaccine. With three functional agents inside, the hydrogel can remarkably induce the immunogenic cell death to enhance the antigen presentation, promoting the dendritic cell maturation and effector T lymphocyte infiltration, as well as relieving the immunosuppressive tumor environment. When inoculated twice at tumor sites, the vaccine demonstrates a substantial antitumor effect in melanoma mouse model, proving its potential as a general platform for synergistic cancer immunotherapy.


Assuntos
Melanoma , Ácidos Nucleicos , Vacinas , Animais , Camundongos , Hidrogéis/metabolismo , Ácidos Nucleicos/metabolismo , Células Dendríticas/metabolismo , Imunoterapia , Vacinação , Microambiente Tumoral , Linhagem Celular Tumoral , Antígeno B7-H1/metabolismo
5.
Am J Transl Res ; 15(8): 5276-5283, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692929

RESUMO

OBJECTIVE: To examine the efficacy of immune checkpoint inhibitors along with chemotherapy in non-small cell lung cancer (NSCLC) and the effect on adverse reactions and serum tumor markers. METHODS: Data of 112 NSCLC patients admitted to Geriatric respiratory department, Xi'an International Medical Center Hospital from February 2018 to March 2021 were analyzed retrospectively. Among them, 54 patients treated with concurrent chemotherapy were labeled as the control group (CG), and 58 patients treated with PD-1/PD-L1 inhibitors in addition to chemotherapy were the observation group (OG). The two groups were compared in terms of immune function indexes, therapeutic efficacy, incidence of adverse reactions, 1-year survival rate, serum tumor markers before and after treatment, and independent risk factors affecting patients' prognosis. RESULTS: Compared to the CG, the OG exhibited significantly better therapeutic efficacy. The levels of IgG, IgA and IgM 6 months after treatment were significantly higher in both groups than those before treatment, and the elevations in the OG were more evident than those in the CG, and the OG demonstrated markedly lower Recombinant Cytokeratin Fragment Antigen 21-1 (CYFRA21-1), Carcinoembryonic antigen (CEA) and Carbohydrate antigen 125 (CA125) levels after treatment than the CG did. Between the two groups, there was no significant difference identified in the incidence of adverse reactions, but the OG was observed to have much higher 1-year survival rate. The pathological stage, differentiation and treatment regimen were independent risk factors affecting patients' prognosis. CONCLUSION: For NSCLC patients, the adoption of PD-1/PD-L1 inhibitors following chemoradiotherapy shows potential in enhancing clinical efficacy, boosting patients' immune function, and improving long-term survival rates, with premising safety profile.

6.
World J Emerg Med ; 14(3): 179-185, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152526

RESUMO

BACKGROUND: This study aimed to explore the changes of programmed death-ligand 1 (PD-L1) and programmed death-1 (PD-1) expression on antigen-presenting cells (APCs) and evaluate their association with organ failure and mortality during early sepsis. METHODS: In total, 40 healthy controls and 198 patients with sepsis were included in this study. Peripheral blood was collected within the first 24 h after the diagnosis of sepsis. The expression of PD-L1 and PD-1 was determined on APCs, such as B cells, monocytes, and dendritic cells (DCs), by flow cytometry. Cytokines in plasma, such as interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), interleukin-4 (IL-4), IL-6, IL-10, and IL-17A were determined by Luminex assay. RESULTS: PD-1 expression decreased significantly on B cells, monocytes, myeloid DCs (mDCs), and plasmacytoid DCs (pDCs) as the severity of sepsis increased. PD-1 expression was also markedly decreased in non-survivors compared with survivors. In contrast, PD-L1 expression was markedly higher on mDCs, pDCs, and monocytes in patients with sepsis than in healthy controls and in non-survivors than in survivors. The PD-L1 expression on APCs (monocytes and DCs) was weakly related to organ dysfunction and inflammation. The area under the receiver operating characteristic curve (AUC) of the PD-1 percentage of monocytes (monocyte PD-1%)+APACHE II model (0.823) and monocyte PD-1%+SOFA model (0.816) had higher prognostic value than other parameters alone. Monocyte PD-1% was an independent risk factor for 28-day mortality. CONCLUSION: The severity of sepsis was correlated with PD-L1 or PD-1 over-expression on APCs. PD-L1 in monocytes and DCs was weakly correlated with inflammation and organ dysfunction during early sepsis. The combination of SOFA or APACHE II scores with monocyte PD-1% could improve the prediction ability for mortality.

7.
World J Gastroenterol ; 29(16): 2502-2514, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37179587

RESUMO

BACKGROUND: Bacteremia, which is a major cause of mortality in patients with acute cholangitis, induces hyperactive immune response and mitochondrial dysfunction. Presepsin is responsible for pathogen recognition by innate immunity. Acylcarnitines are established mitochondrial biomarkers. AIM: To clarify the early predictive value of presepsin and acylcarnitines as biomarkers of severity of acute cholangitis and the need for biliary drainage. METHODS: Of 280 patients with acute cholangitis were included and the severity was stratified according to the Tokyo Guidelines 2018. Blood presepsin and plasma acylcarnitines were tested at enrollment by chemiluminescent enzyme immunoassay and ultra-high-performance liquid chromatography-mass spectrometry, respectively. RESULTS: The concentrations of presepsin, procalcitonin, short- and medium-chain acylcarnitines increased, while long-chain acylcarnitines decreased with the severity of acute cholangitis. The areas under the receiver operating characteristic curves (AUC) of presepsin for diagnosing moderate/severe and severe cholangitis (0.823 and 0.801, respectively) were greater than those of conventional markers. The combination of presepsin, direct bilirubin, alanine aminotransferase, temperature, and butyryl-L-carnitine showed good predictive ability for biliary drainage (AUC: 0.723). Presepsin, procalcitonin, acetyl-L-carnitine, hydroxydodecenoyl-L-carnitine, and temperature were independent predictors of bloodstream infection. After adjusting for severity classification, acetyl-L-carnitine was the only acylcarnitine independently associated with 28-d mortality (hazard ratio 14.396; P < 0.001) (AUC: 0.880). Presepsin concentration showed positive correlation with direct bilirubin or acetyl-L-carnitine. CONCLUSION: Presepsin could serve as a specific biomarker to predict the severity of acute cholangitis and need for biliary drainage. Acetyl-L-carnitine is a potential prognostic factor for patients with acute cholangitis. Innate immune response was associated with mitochondrial metabolic dysfunction in acute cholangitis.


Assuntos
Colangite , Sepse , Humanos , Pró-Calcitonina , Acetilcarnitina , Biomarcadores , Sepse/diagnóstico , Carnitina , Colangite/diagnóstico , Colangite/complicações , Receptores de Lipopolissacarídeos , Fragmentos de Peptídeos , Drenagem , Proteína C-Reativa/análise
8.
Nat Commun ; 13(1): 6094, 2022 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36241751

RESUMO

Promoting the formation of high-oxidation-state transition metal species in a hydroxide catalyst may improve its catalytic activity in the oxygen evolution reaction, which remains difficult to achieve with current synthetic strategies. Herein, we present a synthesis of single-layer NiFeB hydroxide nanosheets and demonstrate the efficacy of electron-deficient boron in promoting the formation of high-oxidation-state Ni for improved oxygen evolution activity. Raman spectroscopy, X-ray absorption spectroscopy, and electrochemical analyses show that incorporation of B into a NiFe hydroxide causes a cathodic shift of the Ni2+(OH)2 → Ni3+δOOH transition potential. Density functional theory calculations suggest an elevated oxidation state for Ni and decreased energy barriers for the reaction with the NiFeB hydroxide catalyst. Consequently, a current density of 100 mA cm-2 was achieved in 1 M KOH at an overpotential of 252 mV, placing it among the best Ni-based catalysts for this reaction. This work opens new opportunities in electronic engineering of metal hydroxides (or oxides) for efficient oxygen evolution in water-splitting applications.

9.
Anal Chem ; 94(38): 13043-13051, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36112636

RESUMO

Accurate and reliable detection of exosomal miRNA can serve as a promising method for early diagnosis of disease and evaluation of therapeutic effects. However, current exosomal miRNA detection methods commonly involve exosome enrichment, containing RNA extraction, and qRT-PCR based quantification, which are expensive and time-consuming. Herein, we develop a DNA zipper-mediated membrane fusion approach for rapid exosomal miRNA detection and cancer diagnosis. First, a lipid vesicle probe containing miR21-targeting molecular beacons (MBs) is constructed and further loaded with zipper DNA constructs (ZDCs) on its surface. Meanwhile, complementary zipper DNA constructs (cZDCs) are introduced on the exosome of interest. Upon mixing them together, zipping between ZDC and cZDC induces the membrane fusion of exosomes and vesicle probes, triggering the recognition of exosomal miR21 by contained MBs and fluorescence emission that can be conveniently detected within 30 min. Importantly, with the assistance of flow cytometry, miR21-overexpressed tumor exosomes derived from either cell culture medium or clinical patient serums can be distinguished from exosomes secreted from normal cells. This approach provides a convenient way to accurately detect the exosomal miRNA, which may hold great potential in liquid biopsy for early cancer diagnosis and monitoring the therapeutic effects during the treatments.


Assuntos
Exossomos , MicroRNAs , Neoplasias , DNA , Exossomos/química , Exossomos/genética , Humanos , Lipídeos , Fusão de Membrana , MicroRNAs/análise , MicroRNAs/genética
10.
World J Emerg Med ; 13(3): 208-214, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35646211

RESUMO

BACKGROUND: Acute pulmonary embolism (APE) with cardiac arrest (CA) is characterized by high mortality in emergency due to pulmonary arterial hypertension (PAH). This study aims to determine whether early pulmonary artery remodeling occurs in PAH caused by massive APE with CA and the protective effects of increasing angiotensin-converting enzyme (ACE) 2-angiotensin (Ang) (1-7)-Mas receptor axis and ACE-Ang II-Ang II type 1 receptor (AT1) axis (ACE2/ACE axes) ratio on pulmonary artery lesion after return of spontaneous circulation (ROSC). METHODS: To establish a porcine massive APE with CA model, autologous thrombus was injected into the external jugular vein until mean arterial pressure dropped below 30 mmHg (1 mmHg=0.133 kPa). Cardiopulmonary resuscitation and thrombolysis were delivered to regain spontaneous circulation. Pigs were divided into four groups of five pigs each: control group, APE-CA group, ROSC-saline group, and ROSC-captopril group, to examine the endothelial pathological changes and expression of ACE2/ACE axes in pulmonary artery with or without captopril. RESULTS: Histological analysis of samples from the APE-CA and ROSC-saline groups showed that pulmonary arterioles were almost completely occluded by accumulated endothelial cells. Western blotting analysis revealed a decrease in the pulmonary arterial ACE2/ACE axes ratio and increases in angiopoietin-2/angiopoietin-1 ratio and expression of vascular endothelial growth factor (VEGF) in the APE-CA group compared with the control group. Captopril significantly suppressed the activation of angiopoietin-2/angiopoietin-1 and VEGF in plexiform lesions formed by proliferative endothelial cells after ROSC. Captopril also alleviated endothelial cell apoptosis by increasing the B-cell lymphoma-2 (Bcl-2)/Bcl-2-associated X (Bax) ratio and decreasing cleaved caspase-3 expression. CONCLUSION: Increasing the ACE2/ACE axes ratio may ameliorate pulmonary arterial remodeling by inhibiting the apoptosis and proliferation of endothelial cells after ROSC induced by APE.

11.
Nat Commun ; 13(1): 63, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039509

RESUMO

Direct implementation of metal-organic frameworks as the catalyst for CO2 electroreduction has been challenging due to issues such as poor conductivity, stability, and limited > 2e- products. In this study, Au nanoneedles are impregnated into a cupric porphyrin-based metal-organic framework by exploiting ligand carboxylates as the Au3+ -reducing agent, simultaneously cleaving the ligand-node linkage. Surprisingly, despite the lack of a coherent structure, the Au-inserted framework affords a superb ethylene selectivity up to 52.5% in Faradaic efficiency, ranking among the best for metal-organic frameworks reported in the literature. Through operando X-ray, infrared spectroscopies and density functional theory calculations, the enhanced ethylene selectivity is attributed to Au-activated nitrogen motifs in coordination with the Cu centers for C-C coupling at the metalloporphyrin sites. Furthermore, the Au-inserted catalyst demonstrates both improved structural and catalytic stability, ascribed to the altered charge conduction path that bypasses the incoherent framework. This study underlines the modulation of reticular metalloporphyrin structure by metal impregnation for steering the CO2 reduction reaction pathway.

12.
Am J Trop Med Hyg ; 106(2): 710-713, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34844206

RESUMO

A 20-year-old female resident of Beijing intended to consume the eggs of the parasitic worm, Taenia saginata, for weight loss; however, she apparently inadvertently ingested Taenia solium (pork tapeworm) eggs, which resulted in disseminated cysticercosis. Cysticerci developed in the brain, tongue, muscles, liver, peritoneum, and subcutaneous tissues. She was administered oral albendazole and praziquantel. After four 10-day courses of treatment, most of the cysts disappeared and she recovered. After 3 years, the patient remains in good health.


Assuntos
Anti-Helmínticos/uso terapêutico , Encéfalo/patologia , Cisticercose/patologia , Taenia solium/patogenicidade , Língua/patologia , Albendazol/uso terapêutico , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/parasitologia , Cisticercose/diagnóstico por imagem , Cisticercose/tratamento farmacológico , Cisticercose/parasitologia , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/parasitologia , Fígado/patologia , Músculos/diagnóstico por imagem , Músculos/parasitologia , Músculos/patologia , Peritônio/diagnóstico por imagem , Peritônio/parasitologia , Peritônio/patologia , Praziquantel/uso terapêutico , Tela Subcutânea/diagnóstico por imagem , Tela Subcutânea/parasitologia , Tela Subcutânea/patologia , Taenia saginata , Taenia solium/crescimento & desenvolvimento , Língua/diagnóstico por imagem , Língua/parasitologia , Resultado do Tratamento , Redução de Peso , Adulto Jovem , Zigoto/crescimento & desenvolvimento , Zigoto/patologia
13.
World J Surg Oncol ; 19(1): 268, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479589

RESUMO

BACKGROUND: Circular RNA 0029803 (circ_0029803) was found to be upregulated in colorectal cancer (CRC) tissues, but its function and underlying molecular mechanism are not studied in CRC. METHODS: The expression levels of circ_0029803, microRNA-216b-5p (miR-216b-5p), and ski-oncogene-like (SKIL) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). RNase R treatment was used to affirm the existence of circ_0029803. Cell proliferation, apoptosis, migration, and invasion were assessed by colony formation, flow cytometry, and Transwell assays, respectively. A glucose and lactate assay kit was used to detect glucose consumption and lactate production. Western blot was applied to analyze the levels of all proteins. Dual-luciferase reporter assay was performed to assess the relationship between miR-216b-5p and circ_0029803 or SKIL. Tumor xenograft models were established to elucidate the effect of circ_0029803 in vivo. RESULTS: Circ_0029803 expression was enhanced in CRC tissues and cells, and the 5-year overall survival rate of patients with high circ_0029803 expression was substantially reduced. Circ_0029803 depletion retarded proliferation, migration, invasion, EMT and glycolysis of CRC cells in vitro as well as the tumor growth in vivo. Mechanically, circ_0029803 could serve as miR-216b-5p sponge to regulate its expression, and miR-216b-5p knockdown reversed the inhibition of si-circ_0029803 on the malignant behaviors of CRC cells. Additionally, as the target mRNA of miR-216b-5p, SKIL could counteract the inhibitory effect of miR-216b-5p on the development of CRC cells. Importantly, silencing circ_0029803 reduced SKIL expression via sponging miR-216b-5p. CONCLUSION: Circ_0029803 knockdown hindered proliferation, migration, invasion, EMT, and glycolysis and promoted apoptosis in CRC cells by modulating the miR-216b-5p/SKIL axis.


Assuntos
Neoplasias Colorretais , Peptídeos e Proteínas de Sinalização Intracelular/genética , MicroRNAs , RNA Circular , Animais , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Prognóstico , Proteínas Proto-Oncogênicas , RNA Circular/genética
14.
Ann Transl Med ; 9(22): 1662, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34988171

RESUMO

BACKGROUND: Artificial intelligence (AI) is used to solve the problem of missed diagnosis of polyps in colonoscopy, which has been proved to improve the detection rate of adenomas. The aim of this review was to evaluate the diagnostic performance of AI-assisted detection and classification of polyps in colonoscopy. METHODS: The literature search was undertaken on 4 electronic databases (PubMed, Web of Science, Embase, and Cochrane Library). The inclusion criteria were as follows: studies reporting AI-assisted detection and classification of polyps; studies containing patients, images, or videos receiving AI-assisted diagnosis; studies which included AI-assisted diagnosis and reported classification based on histopathology; and studies providing accurate diagnostic data. Non-English language studies, case-reports, reviews, meeting abstracts and so on were excluded. The Quality Assessment of Diagnostic Accuracy Studies-2 scale was used to evaluate the quality of literature and the Stata 13.0 software was used to perform meta-analysis. RESULTS: Twenty-six articles were included with all of medium quality. Meta-analysis showed none of literature had any obvious publication bias. The application of AI in detection of colorectal polyps achieved a sensitivity of 0.95 [95% confidence interval (CI): 0.89-0.98] and an area under the curve (AUC) of 0.79 (95% CI: 0.79-0.82). In the AI-assisted classification, the sensitivity was 0.92 (95% CI: 0.88-0.95) with a specificity of 0.82 (95% CI: 0.71-0.89) and an AUC of 0.94 (95% CI: 0.92-0.96). For the classification of diminutive polyps, the AI-assisted technique yielded a sensitivity of 0.95 (95% CI: 0.94-0.97), a specificity of 0.88 (95% CI: 0.74-0.95), and an AUC of 0.97 (95% CI: 0.95-0.98). For AI-assisted classification under magnifying endoscopy, the sensitivity was 0.954 (95% CI: 0.92-0.96) with a specificity of 0.95 (95% CI: 0.80-0.99) and an AUC of 0.97 (95% CI: 0.95-0.98). DISCUSSION: The AI-assisted technique demonstrates impressive accuracy for the detection and characterization of colorectal polyps and can be expected to be a novel auxiliary diagnosis method. Our study has inevitable limitations including heterogeneity due to different AI systems and the inability to further analyze the specificity and sensitivity of AI for different types of endoscopes.

15.
Sci Bull (Beijing) ; 66(1): 62-68, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36654315

RESUMO

Among all CO2 electroreduction products, methane (CH4) and ethylene (C2H4) are two typical and valuable hydrocarbon products which are formed in two different pathways: hydrogenation and dimerization reactions of the same CO intermediate. Theoretical studies show that the adsorption configurations of CO intermediate determine the reaction pathways towards CH4/C2H4. However, it is challenging to experimentally control the CO adsorption configurations at the catalyst surface, and thus the hydrocarbon selectivity is still limited. Herein, we seek to synthesize two well-defined copper nanocatalysts with controllable surface structures. The two model catalysts exhibit a high hydrocarbon selectivity toward either CH4 (83%) or C2H4 (93%) under identical reduction conditions. Scanning transmission electron microscopy and X-ray absorption spectroscopy characterizations reveal the low-coordination Cu0 sites and local Cu0/Cu+ sites of the two catalysts, respectively. CO-temperature programed desorption, in-situ attenuated total reflection Fourier transform infrared spectroscopy and density functional theory studies unveil that the bridge-adsorbed CO (COB) on the low-coordination Cu0 sites is apt to be hydrogenated to CH4, whereas the bridge-adsorbed CO plus linear-adsorbed CO (COB + COL) on the local Cu0/Cu+ sites are apt to be coupled to C2H4. Our findings pave a new way to design catalysts with controllable CO adsorption configurations for high hydrocarbon product selectivity.

16.
Neurochem Res ; 45(8): 1953-1961, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32623664

RESUMO

Oxidative stress-mediated neuron damage is considered an important contributor to the pathogenesis and development of neurodegenerative diseases. Although ß-asarone is widely known for its neuroprotective pharmacological properties, the exact mechanism of ß-asarone against oxidative stress has not been fully elucidated. The aim of the present study was to investigate underlying mechanisms of ß-asarone against oxidative damage in PC12 cells. Our results demonstrated that the treatment of ß-asarone significantly alleviated the reduction in cell viability and the excessive accumulation of lactate dehydrogenase (LDH), malondialdehyde (MDA) and reactive oxygen species (ROS) by increasing the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH). Moreover, ß-asarone pretreatment also activated nuclear factor 2 erythroid-related factor 2 (Nrf2) and its downstream target heme oxygenase-1 (HO-1), which was involved in quenching reactive oxygen to inhibit oxidative stress. Furthermore, when silenced by Nrf2 siRNA, the protective effect of ß-asarone was reduced and the oxidative stress induced by H2O2 was enhanced. In conclusion, our findings revealed that ß-asarone could reduce oxidative stress via activating Nrf2/HO-1 pathway in PC12 cells, highlighting the potential therapeutic role of ß-asarone in neurodegenerative diseases.


Assuntos
Derivados de Alilbenzenos , Anisóis , Antioxidantes , Peróxido de Hidrogênio , Transdução de Sinais , Animais , Ratos , Derivados de Alilbenzenos/farmacologia , Anisóis/farmacologia , Antioxidantes/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Heme Oxigenase (Desciclizante)/metabolismo , Peróxido de Hidrogênio/farmacologia , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Células PC12 , Espécies Reativas de Oxigênio/metabolismo , RNA Interferente Pequeno/genética , Transdução de Sinais/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo
17.
Biomaterials ; 245: 119976, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32213362

RESUMO

Photothermal therapy (PTT) normally requires to maintain the temperature of tumor lesions above 50 °C, which potentially induces local inflammation and tumor metastasis. To avoid these side effects, it is vital to achieve effective antitumor efficacy at relatively low temperature (42-45 °C) during the PTT treatment. Herein, we design a polydopamine (PDA)-coated nucleic acid nanogel as a therapeutic complex for siRNA-mediated low-temperature PTT. First, siRNAs that target the heat-shock-protein 70 (Hsp70) serve as crosslinkers to guide the DNA-grafted polycaprolactone (DNA-g-PCL) assemble into nanosized hydrogel particles through nucleic acid hybridization. Thereafter, the obtained siRNA-embedded nanogels are further coated with a thin layer of polydopamine, which not only protects the nanogels against enzymatic degradation but also endows the nanogels with excellent photothermal conversion capacity under near infrared (NIR) light irradiation. After surface PEGylation, this triple shield siRNA delivery complex shows the capability of effective ablating the tumor under relatively mild condition.


Assuntos
Hipertermia Induzida , Ácidos Nucleicos , Indóis , Nanogéis , Fototerapia , Terapia Fototérmica , Polietilenoglicóis , Polietilenoimina , Polímeros , RNA Interferente Pequeno , Temperatura
18.
Int J Mol Med ; 43(4): 1575-1584, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30816437

RESUMO

Acute pulmonary embolism (APE) with cardiac arrest (CA) is associated with a high mortality rate. Even upon return of the spontaneous circulation (ROSC), APE­CA survivors are prone to myocardial cell apoptosis, a key cellular mechanism that induces heart failure. A recent study by our group discovered a post­resuscitation imbalance in the serum angiotensin­converting enzyme (ACE)2/ACE axis of the renin­angiotensin system (RAS), as well as regressive cardiac function in a porcine model of APE­CA. However, it has remained elusive how this imbalance in the ACE2/ACE axis affects myocardial cell apoptosis. In the present study, western blot and immunohistochemical analyses demonstrated that the RAS was only activated in the left myocardium, as evidenced by a decreased ACE2/ACE ratio following APE­CA and ROSC, but not the right myocardium. Ultrastructural analysis confirmed myocardial apoptosis in the left and right myocardium. Furthermore, B­cell lymphoma 2 (Bcl­2)­associated X protein (Bax) and caspase­3 levels were elevated and Bcl­2 levels were decreased in the left myocardium following APE­CA and ROSC. Treatment with the ACE inhibitor captopril for 30 min after initiation of ROSC prevented the increase in Bax and the decrease in Bcl­2 in the left myocardium compared with that in saline­treated pigs. Captopril also inhibited the activation of extracellular signal­regulated kinase (ERK)1/2 in the left myocardium. The results of the present study suggest that an imbalance in the ACE2/ACE axis has an important role in myocardial apoptosis following APE­CA, which may be attributed to decreased ERK1/2 activation. In addition, it was indicated that captopril prevents apoptosis in the left myocardium after ROSC.


Assuntos
Apoptose , Parada Cardíaca/enzimologia , Parada Cardíaca/etiologia , Miocárdio/enzimologia , Miocárdio/patologia , Peptidil Dipeptidase A/metabolismo , Embolia Pulmonar/complicações , Doença Aguda , Enzima de Conversão de Angiotensina 2 , Animais , Apoptose/efeitos dos fármacos , Captopril/farmacologia , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Miocárdio/ultraestrutura , Sistema Renina-Angiotensina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Suínos
19.
J Cell Biochem ; 120(6): 9409-9420, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30548678

RESUMO

We investigated that microRNA (miRNA)-141 protects against epilepsy-induced apoptosis and its reaction mechanism. The serum expression of miRNA-141 in epilepsy model mice and control volunteer was measured by quantitative reverse-transcription polymerase chain reaction. We found that miRNA-141 serum expression was upregulated in patients with epilepsy. Overexpression of miRNA-141 induced nerve cell apoptosis, suppressed proliferation, promoted caspase-3/9, Bax and p53 protein expression, and reduced silent information regulator 1 (SIRT1) protein expression in vitro model. In addition, the downexpression miRNA-141 using si-miRNA-141 reduced nerve cell apoptosis and increased proliferation, suppressed caspase-3/9, Bax and p53 protein expression, induced SIRT1 protein expression. SIRT1 inhibitor (nicotinamide) decreased SIRT1, reduced the effects of miRNA-141 on nerve cell apoptosis in vitro model of epilepsy through SIRT1/p53. SIRT1 agonist also reduced the effects of miRNA-141 overexpression on nerve cell apoptosis in vitro model of epilepsy through SIRT1/p53. Our preliminary findings indicate that anti-miRNA-141 protects against epilepsy-induced apoptosis via SIRT1/p53 expression.


Assuntos
Epilepsia/genética , MicroRNAs/genética , Sirtuína 1/genética , Proteína Supressora de Tumor p53/genética , Animais , Apoptose/genética , Modelos Animais de Doenças , Epilepsia/sangue , Epilepsia/patologia , Epilepsia/terapia , Regulação da Expressão Gênica/genética , Humanos , Camundongos , MicroRNAs/antagonistas & inibidores , MicroRNAs/sangue , Neurônios/metabolismo , Neurônios/patologia , Substâncias Protetoras/farmacologia , Transdução de Sinais/genética , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/sangue , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/sangue
20.
Mol Med Rep ; 17(3): 4221-4228, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29328448

RESUMO

Acute pulmonary embolism (APE) is frequently reported in patients with cardiac arrest (CA) in emergency care. Pneumocyte apoptosis is commonly observed in the lungs following an APE. An important pathological mechanism evoking apoptosis during a lipopolysaccharide­induced acute lung injury is the angiotensin­converting enzyme 2 (ACE2)/ACE imbalance. The present study uses a porcine model to examine the anti­apoptotic effects of captopril on APE­CA and the return of spontaneous circulation (ROSC). Pigs were randomly assigned into four groups: Control, APE­CA, ROSC­saline, and ROSC­captopril. Surviving pigs were euthanized at 6 h and lungs were isolated for analysis using several biochemical assays. Compared with the control group, the ACE2/ACE ratio was lower in the APE­CA and ROSC pigs. In addition, APE­CA pigs had higher Bcl­2­associated X protein (Bax) and cleaved caspase­3 levels, and lower B­cell lymphoma­2 (Bcl­2) level compared to control pigs. Captopril treatment reduced lung apoptosis, as demonstrated by lower TUNEL­positive cells, higher Bcl­2, and lower cleaved caspase­3 protein levels in the lung. Notably, the ACE2/ACE ratio was positively correlated with Bcl­2 protein levels and Bcl­2/Bax ratio. In conclusion, captopril has a protective effect against lung apoptosis following ROSC and that maintaining the balance of the ACE2/ACE axis is important for inhibiting pulmonary apoptosis during APE.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Captopril/farmacologia , Parada Cardíaca/tratamento farmacológico , Peptidil Dipeptidase A/genética , Embolia Pulmonar/tratamento farmacológico , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/patologia , Células Epiteliais Alveolares/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/patologia , Enzima de Conversão de Angiotensina 2 , Animais , Apoptose/efeitos dos fármacos , Caspase 3/genética , Caspase 3/metabolismo , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Parada Cardíaca/induzido quimicamente , Parada Cardíaca/genética , Parada Cardíaca/patologia , Lipopolissacarídeos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Pulmão/patologia , Masculino , Peptidil Dipeptidase A/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Embolia Pulmonar/induzido quimicamente , Embolia Pulmonar/genética , Embolia Pulmonar/patologia , Transdução de Sinais , Suínos
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