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101.
This study aimed to compare the background echotexture (BE) between automated breast ultrasound (ABUS) and handheld breast ultrasound (HHUS) and evaluate the correlation of BE with mammographic (MG) density and background parenchymal enhancement (BPE) on magnetic resonance imaging (MRI). A total of 212 women with newly diagnosed breast cancer who had undergone preoperative ABUS, HHUS, MG, and MRI were included. Two breast radiologists blinded to the menopausal status analyzed the BE of the contralateral breasts of the patients with breast cancer in consensus. The MG density and BPE of breast MRI on the radiologic reports were compared with the BE in the ultrasound. We used the cumulative link mixed model to compare the BE and Spearman rank correlation to evaluate the association between BE with MG density and BPE. BE was more heterogeneous in ABUS than in HHUS (P < .001) and in the premenopausal group than in the postmenopausal group (P < .001). The heterogeneity of BE in the premenopausal group was higher with ABUS than with HHUS (P = .013). BE and MG density showed a moderate correlation in the postmenopausal group, but a weak correlation in the premenopausal group. BE and BPE showed moderate correlations only in the premenopausal group. ABUS showed a more heterogeneous BE, especially in the premenopausal group. Therefore, more attention is required to interpret ABUS screening in premenopausal women.  相似文献   
102.
假肌源性血管内皮瘤(pseudomyogenic hemangioendothelioma,PHE)是一种十分罕见的血管源性肿瘤,组织学上肿瘤性血管和内皮分化的形态特征皆不明显,易与上皮样肉瘤、上皮样血管内皮细胞瘤或肌源性肿瘤相混淆。PHE好发于青年男性,多见于四肢,典型表现为单个肢体多个中心侵犯,可累及皮肤及皮下组织各层,常伴有显著的疼痛。PHE组织病理特点为肿瘤呈浸润性生长,肿瘤细胞主要由疏松的呈束状或片状分布的梭形细胞组成,形态上可出现横纹肌母细胞样或上皮样细胞,可伴有炎症细胞浸润,以中性粒细胞多见,核异型及核分裂像少见。肿瘤细胞常阳性表达细胞角蛋白(cytokeratin,CK)、ETS相关基因(ETS-related gene,ERG)、Friend白血病病毒整合基因(Friend leukemia virus integration 1,FLI1)和整合酶相互作用分子1(integrase interactor 1,INI1),部分患者阳性表达CD31。1例青年女性因发现皮下肿块伴剧烈疼痛就诊,先后被误诊为带状疱疹、低度恶性纤维组织细胞瘤和上皮样血管内皮细胞瘤。本文结合相关...  相似文献   
103.
目的通过Meta分析对使用人工补片进行食管裂孔重建的效果和安全性进行评价。方法检索Pubmed和Cochrane数据库2007年4月10日以前有关使用人工补片进行食管裂孔重建的随机对照实验,使用Cochrane图书馆提供的Review Manager4.2软件对入选实验的数据进行合并分析。主要评价指标包括术后裂孔疝发生率和由补片引起的脏器磨损。结果有7项随机对照实验,其中3项实验满足纳入标准和排除标准而入选Meta分析。共有280名研究对象纳入分析,其中使用人工补片进行裂孔重建的患者(n=137)在随访期内有8例(5.83%)发生裂孔疝,对照组(n=143)有33例(23.08%)发生裂孔疝,相对危险度RR=0.30(95%CI,0.15-0.62,P=0.001),随访期内没有观察到因补片磨损引起的脏器损伤。结论使用人工补片进行裂孔重建明显降低术后近期裂孔疝的发生危险,具有良好的应用前景,但远期效果和安全性有待长期观察的结果进一步明确。  相似文献   
104.
IL‐27 is an anti‐inflammatory cytokine that triggers enhanced antitumor immunity, particularly cytotoxic T lymphocyte responses. In the present study, we sought to develop IL‐27 into a therapeutic adjutant for adoptive T cell therapy using our well‐established models. We have found that IL‐27 directly improved the survival status and cytotoxicity of adoptive OT‐1 CD8+ T cells in vitro and in vivo. Meanwhile, IL‐27 treatment programs memory T cell differentiation in CD8+ T cells, characterized by upregulation of genes associated with T cell memory differentiation (T‐bet, Eomes, Blimp1, and Ly6C). Additionally, we engineered the adoptive OT‐1 CD8+ T cells to deliver IL‐27. In mice, the established tumors treated with OT‐1 CD8+ T‐IL‐27 were completely rejected, which demonstrated that IL‐27 delivered via tumor antigen–specific T cells enhances adoptive T cells’ cancer immunity. To our knowledge, this is the first application of CD8+ T cells as a vehicle to deliver IL‐27 to treat tumors. Thus, this study demonstrates IL‐27 is a feasible approach for enhancing CD8+ T cells’ antitumor immunity and can be used as a therapeutic adjutant for T cell adoptive transfer to treat cancer.  相似文献   
105.
This study was conducted to evaluate the predictive value of spleen stiffness-spleen size-to-platelet ratio risk score (SSPS) as a noninvasive predictor of esophageal varices (EVs) and to compare it with others.In this retrospective study, from April 2017 to October 2018, a total of 65 patients with hepatitis B virus-related cirrhosis who underwent the liver and spleen stiffness (LS, and SS) measurements by 2 dimensional-shear wave elastography and endoscopic evaluation for EVs were enrolled. Liver stiffness-spleen size-to-platelet ratio risk score (LSPS) and SSPS were calculated. The prognostic values were assessed by the area under the receiver operating characteristic curve (AUC).Twenty-six patients had no EV on endoscopy. Among 39 patients who had EVs, 12 patients had high risk EVs. The AUCs of the LS value, SS value, LSPS, and SSPS for predicting EVs were 0.72, 0.77, 0.80, and 0.85, respectively. The AUCs of the LS value, SS value, LSPS, and SSPS for predicting high-risk EVs were 0.55, 0.78, 0.67, and 0.80, respectively. SSPS had the highest specificity, at 96.15%, for predicting EVs.SSPS may be beneficial to exclude from having EVs and it is expected that the frequency of performing endoscopies for screening EVs can be reduced.  相似文献   
106.
107.
BackgroundAs the coronavirus disease 2019 (COVID-19) pandemic continues, there are concerns regarding waning immunity and the emergence of viral variants. The immunogenicity of Ad26.COV2.S against wild-type (WT) and variants of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) needs to be evaluated.MethodThis prospective cohort study was conducted between June 2021 and January 2022 at two university hospitals in South Korea. Healthy adults who were scheduled to be vaccinated with Ad26.COV2.S were enrolled in this study. The main outcomes included anti-spike (S) IgG antibody and neutralizing antibody responses, S-specific T-cell responses (interferon-γ enzyme-linked immunospot assay), solicited adverse events (AEs), and serious AEs.ResultsFifty participants aged ≥ 19 years were included in the study. Geometric mean titers (GMTs) of anti-S IgG were 0.4 U/mL at baseline, 5.2 ± 3.0 U/mL at 3–4 weeks, 55.7 ± 2.4 U/mL at 5–8 weeks, and 81.3 ± 2.5 U/mL at 10–12 weeks after vaccination. GMTs of 50% neutralizing dilution (ND50) against WT SARS-CoV-2 were 164.6 ± 4.6 at 3-4 weeks, 313.9 ± 3.6 at 5–8 weeks, and 124.4 ± 2.6 at 10–12 weeks after vaccination. As for the S-specific T-cell responses, the median number of spot-forming units/106 peripheral blood mononuclear cell was 25.0 (5.0–29.2) at baseline, 60.0 (23.3–178.3) at 5-8 weeks, and 35.0 (13.3–71.7) at 10–12 weeks after vaccination. Compared to WT SARS-CoV-2, ND50 against Delta and Omicron variants was attenuated by 3.6-fold and 8.2-fold, respectively. The most frequent AE was injection site pain (82%), followed by myalgia (80%), fatigue (70%), and fever (50%). Most AEs were grade 1–2, and resolved within two days.ConclusionSingle-dose Ad26.COV2.S was safe and immunogenic. NAb titer and S-specific T-cell immunity peak at 5–8 weeks and rather decrease at 10–12 weeks after vaccination. Cross-reactive neutralizing activity against the Omicron variant was negligible.  相似文献   
108.
BackgroundThe rapid urease test (RUT) is a major diagnostic tool for detecting Helicobacter pylori infection. This study aimed to establish an objective method for measuring the color changes in the RUT kit to improve the test’s diagnostic accuracy.MethodsA UV-visible spectrophotometer was selected as the colorimeter; experiments were conducted in three stages to objectively identify the color changes in the RUT kit.ResultsFirst, the urea broth solution showed an identifiable color change from yellow to red as the pH increased by 0.2. The largest transmittance difference detected using the UV-visible spectrophotometer was observed at a 590-nm wavelength. Second, the commercialized RUT kit also showed a gradual color change according to the pH change detected using the UV-visible spectrophotometer. Third, 13 cases of negative RUT results with a biopsy specimen and 16 of positive RUT results were collected. The transmittance detected using the UV-visible spectrophotometer showed a clear division between the positive and negative RUT groups; the largest difference was observed at a 559-nm wavelength. The lowest transmittance in the negative RUT group was 64, while the highest in the positive RUT group was 56, at the 559-nm wavelength. The UV-visible spectrophotometry reading showed a consistency of 92.7% compared with that of manual reading.ConclusionA transmittance of 60 at a 559-nm wavelength detected using UV-visible spectrophotometer can be used as a cutoff value for interpreting RUT results; this will help develop an automatic RUT kit reader with a high accuracy.  相似文献   
109.
Sarcopenia refers to a decline in muscle mass and strength with age, causing significant impairment in the ability to carry out normal daily functions and increased risk of falls and fractures, eventually leading to loss of independence. Maintaining protein homeostasis is an important factor in preventing muscle loss, and the decrease in muscle mass is caused by an imbalance between anabolism and catabolism of muscle proteins. Although β-sitosterol has various effects such as anti-inflammatory, protective effect against nonalcoholic fatty liver disease (NAFLD), antioxidant, and antidiabetic activity, the mechanism of β-sitosterol effect on the catabolic pathway was not well known. β-sitosterol was assessed in vitro and in vivo using a dexamethasone-induced muscle atrophy mice model and C2C12 myoblasts. β-sitosterol protected mice from dexamethasone-induced muscle mass loss. The thickness of gastrocnemius muscle myofibers was increased in dexamethasone with the β-sitosterol treatment group (DS). Grip strength and creatine kinase (CK) activity were also recovered when β-sitosterol was treated. The muscle loss inhibitory efficacy of β-sitosterol in dexamethasone-induced muscle atrophy in C2C12 myotube was also verified in C2C12 myoblast. β-sitosterol also recovered the width of myotubes. The protein expression of muscle atrophy F-box (MAFbx) was increased in dexamethasone-treated animal models and C2C12 myoblast, but it was reduced when β-sitosterol was treated. MuRF1 also showed similar results to MAFbx in the mRNA level of C2C12 myotubes. In addition, in the gastrocnemius and tibialis anterior muscles of mouse models, Forkhead Box O1 (FoxO1) protein was increased in the dexamethasone-treated group (Dexa) compared with the control group and reduced in the DS group. Therefore, β-sitosterol would be a potential treatment agent for aging sarcopenia.  相似文献   
110.
Cardiovascular disease (CVD) is a group of diseases affecting the heart and blood vessels and is the leading cause of morbidity and mortality worldwide. Increasingly more evidence has shown that the senescence of vascular endothelial cells is the key to endothelial dysfunction and cardiovascular diseases. Anthocyanin is a type of water-soluble polyphenol pigment and secondary metabolite of plant-based food widely existing in fruits and vegetables. The gut microbiome is involved in the metabolism of anthocyanins and mediates the biological activities of anthocyanins and their metabolites, while anthocyanins also regulate the growth of specific bacteria in the microbiota and promote the proliferation of healthy anaerobic flora. Accumulating studies have shown that anthocyanins have antioxidant, anti-inflammatory, and anti-aging effects. Many animal and in vitro experiments have also proven that anthocyanins have protective effects on cardiovascular-disease-related dysfunction. However, the molecular mechanism of anthocyanin in eliminating aging endothelial cells and preventing cardiovascular diseases is very complex and is not fully understood. In this systematic review, we summarize the metabolism and activities of anthocyanins, as well as their effects on scavenging senescent cells and cardioprotection.  相似文献   
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