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《Acta histochemica》2023,125(5):152046
The close interaction between male germ cells and Sertoli cells, a type of somatic cell found in the seminiferous tubules of mammalian testis, is essential for the normal progression of spermatogenesis in mammals. Vimentin is an intermediate filament protein that primarily provides mechanical support, preserves cell shape, and maintains the nuclear position, and it is often used as a marker to identify Sertoli cells. Vimentin is known to be involved in many diseases and aging processes; however, how vimentin is related to spermatogenic dysfunction and the associated functional changes is still unclear. In a previous study, we reported that vitamin E deficiency affected the testes, epididymis, and spermatozoa of mice, accelerating the progression of senescence. In this study, we focused on the Sertoli cell marker vimentin and explored the relationship between the cytoskeletal system of Sertoli cells and spermatogenic dysfunction using testis tissue sections that caused male reproductive dysfunction with vitamin E deficiency. The immunohistochemical analysis showed that the proportion of the vimentin-positive area in seminiferous tubule cross-sections was significantly increased in testis tissue sections of the vitamin E-deficient group compared with the proportion in the control group. The histological analysis of testis tissue sections from the vitamin E-deficient group showed that vimentin-positive Sertoli cells were greatly extended from the basement membrane, along with an increased abundance of vimentin. These findings suggest that vimentin may be a potential indicator for detecting spermatogenic dysfunction.  相似文献   
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ObjectiveMost patients with localization-related epilepsy (LRE) and genetic generalized epilepsy (GGE) are classified based on semiology and video-EEG, but both features occasionally fail to provide a definitive diagnosis. Several reliable lateralizing signs have been described, although hand and finger posturing has received little attention. We sought to investigate the frequency of index-finger pointing (IFP) during generalized motor convulsions as a lateralizing semiology in LRE.MethodsWe retrospectively analyzed 98 videos of generalized convulsions in 64 consecutive patients who were admitted for diagnostic video-EEG (vEEG). Demographics were recorded, and IFP ipsilateral, contralateral, and bilateral to vEEG ictal correlate was compared between LRE, GGE, and nonepileptic attacks (NEAs). The angle of IFP was measured to quantify the mean degree of IFP in “pointers” versus “nonpointers”. Statistical analysis was completed using JMP 9.0.ResultsIndex-finger pointing was more common in epileptic GTC seizures than in convulsive NEAs (83.6% vs 12.0%; p < 0.001) and was more common in LRE compared with GGE (96% vs 56.6%; p  0.001). The frequency of contralateral, ipsilateral, or bilateral IFP did not differ between LRE and GGE. The average angle at the MCP joint in “pointers” was 35.8° (SD 22.0°) and in “nonpointers” 3.0° (SD 7.2°).SignificanceThis is the first study to examine hand and finger postures as a clinical sign to help classify epilepsy type. The presence of IFP was more common in patients with LRE than in patients with GGE and very rarely occurred in NEA. Index-finger pointing and other hand semiologies are potentially quantifiable localizing signs to aid in the characterization of patients with GTC seizures.  相似文献   
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Background: Portal vein tumor thrombosis(PVTT) is regarded as a contraindication for liver transplantation(LT) in hepatocellular carcinoma(HCC). However, some of these patients may have a favorable prognosis after LT. In this study, we evaluated the biological behavior of HCC with PVTT using tumor biomarker(alpha-fetoprotein, AFP) and 18 F-FDG positron emission tomography(tumor standard uptake value) to identify a subset of patients who may be suitable for LT. Methods: Seventy-five HCC-PVTT liver recipients transplanted during February 2016 and June 2018 were analyzed. Different pre-transplant prognostic factors were identified by univariate and multivariate analyses. PVTT status was identified following Vp classification(Vp1-Vp4). Results: Three-year recurrence-free survival and overall survival rates were 40% and 65.4% in Vp2-Vp3 PVTT patients, 21.4% and 30.6% in Vp4 PVTT patients( P 0.05). Total tumor diameter 8 cm, pretransplant AFP level 10 0 0 ng/m L and intrahepatic tumor maximal standard uptake value(SUVmaxtumor 5) were independent risk factors for HCC recurrence and overall survival after LT in Vp2-3 PVTT patients. Low risk patients were defined as total tumor diameter ≤8 cm; or if total tumor diameter more than 8 cm, with both pre-transplant AFP level less than 10 0 0 ng/m L and intrahepatic tumor SUVmax less than 5, simultaneously. Twenty-two Vp2-3 PVTT HCC patients(46.8%) were identified as low risk patients, and their 3-year recurrence-free and overall survival rates were 67.6% and 95.2%, respectively. Conclusions: Patients with segmental or lobar PVTT and biologically favorable tumors defined by AFP and 18 F-FDG SUVmax might be suitable for LT.  相似文献   
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背景 阿霉素(DOX)是一种常见的强效蒽环类抗肿瘤药物,被广泛应用于各类肿瘤尤其是实体性肿瘤的治疗中。然而,DOX有较强的心脏毒性,临床表现为不可逆性心肌病和充血性心力衰竭。黄酒多酚(YWPC)是从绍兴黄酒中提取的多酚类物质,具有抗炎、抗氧化等生理活性,对DOX所致心肌损伤有一定缓解作用,但其作用机制还不明晰。 目的 通过体内外实验探讨YWPC减轻DOX心肌损伤的作用机制。 方法 动物实验:使用SD大鼠建立DOX心肌损伤模型,分为对照组、YWPC组、DOX组与DOX+YWPC组;取心脏组织进行MASSON染色、原位末端标记(TUNEL)染色及免疫组织化学染色,取血清测定乳酸脱氢酶(LDH)水平,并用动物组织蛋白、Western Blot法检测凋亡水平〔B淋巴细胞瘤-2蛋白(Bcl-2)、Bcl-2相关X蛋白(Bax)〕及沉默调节蛋白3(SIRT3)表达水平变化。体外实验:通过1 μmol/L DOX干预H9C2细胞24 h建立DOX诱导H9C2细胞损伤模型,先将一批H9C2细胞分为对照组、DOX组、DOX+YWPC(1 mg/L)组、DOX+YWPC(10 mg/L)与DOX+YWPC(100 mg/L)5组,采用CCK-8法检测H9C2细胞活力,通过Western Blot法检测凋亡水平及SIRT3表达水平变化;之后将另一批H9C2细胞分为对照组、DOX组、DOX+YWPC组、DOX+SIRT3抑制剂(3-TYP)组及DOX+YWPC+3-TYP组,通过3-TYP抑制SIRT3蛋白活性,通过Western Blot法检测凋亡水平及SIRT3表达水平变化,进一步明确SIRT3在YWPC减轻DOX心肌损伤中的作用。 结果 动物实验中,大鼠心肌切片通过MASSON染色后可见:DOX组大鼠心肌纤维排列紊乱,大量蓝色胶原纤维贯穿心肌纤维;DOX+YWPC组大鼠心肌切片纹理部分恢复,蓝色胶原纤维减少。DOX组胶原纤维占比、血清LDH水平高于对照组、DOX+YWPC组(P<0.05)。DOX组Bcl-2/Bax比值、SIRT3表达水平低于对照组、DOX+YWPC组(P<0.05);DOX组大鼠心肌切片中代表凋亡的绿色亮点明显增多,呈片状分布,而经YWPC治疗后凋亡亮点减少。体外实验中,DOX组吸光度值、Bcl-2/Bax比值、SIRT3表达水平低于对照组、DOX+YWPC(1 mg/L)组、DOX+YWPC(10 mg/L)组、DOX+YWPC(100 mg/L)组(P<0.05),DOX组、DOX+3-TYP组Bcl-2/Bax比值、SIRT3表达水平低于对照组(P<0.05);DOX+YWPC+3-TYP组Bcl-2/Bax比值低于DOX+YWPC组(P<0.05),DOX+YWPC组与DOX+YWPC+3-TYP组SIRT3表达水平比较,差异无统计学意义(P>0.05)。 结论 YWPC可以通过调节SIRT3表达水平减轻DOX心肌损伤,抑制SIRT3会降低YWPC的作用。  相似文献   
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《Foot and Ankle Surgery》2020,26(3):289-294
BackgroundThe purpose of the study is to investigatethe prevalence of posterior malleolus intercalary fragment (ICF) in adult ankle fractures; to analyze the morphological characteristics of ICF; and its mechanism.MethodsRetrospectively, 247 cases of posterior malleolus fractures (PMF) were included in 369 cases of adult ankle fractures. The prevalence of ICF, relationship between type of ankle fracture, posterior malleolar fracture and the ICF was studied.ResultsAmong 369 cases, the ICF was found in 43% of the PMF and 29% of the hospitalized unstable ankle fractures. Position of ICF is posterolateral in 68 (64%), mid posterior in 20 (19%) and posteromedial in 18 (17%) cases. The prevalence of ICF was 70% in Bartoníček classification type III fractures, which was significantly higher than type I, II and IV.ConclusionsThe highest incidence occurs in Bartoníček III type fracture. The study helps in further understanding and treatment of the PMF.Level of evidenceLevel IV, case series.  相似文献   
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《Foot and Ankle Surgery》2020,26(3):308-313
BackgroundAlthough the lateral compartment of the leg is characterized by a high degree of morphological variation, very little information exists on the morphological variability of the fibularis brevis muscle (FBM) and fibularis digiti quinti (FDQ). The main aim of the study was to characterize the morphology of the FBM tendon and its accessory bands, to classify them and to determine the incidence of FDQ. The work attempts to determine the relationship between the types of the insertion of the FBM tendon and the occurrence of FDQ.MethodsClassical anatomical dissection was performed on 102 lower limbs fixed in 10% formalin solution. The morphology of the insertion of the FBM and of the FDQ was evaluated.ResultsThe FBM was present in all specimens. Two types of insertion were observed, the most common being Type I (70.6%): a single distal attachment in which the tendon inserts into the tuberosity at the base of the fifth metatarsal bone. The second most common was Type II (29.4%); this group was divided into three subtypes (A–C). The FDQ was present in 17.7% of specimens and always with Type I FBM.ConclusionBoth the FBM tendon and FDQ present significant morphological variation. Two main types of the FBM tendon determine the presence of the FDQ.Level of evidenceII Basic Science Research.  相似文献   
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《Foot and Ankle Surgery》2020,26(3):328-333
BackgroundDespite the promising results of ankle joint arthroplasty, the tibiotalocalcaneal (TTC) arthrodesis remains an established procedure in treatment of combined pathology of the ankle and subtalar joint. Despite the promising results in biomechanical investigations, nonunion rates of up to 24% are described in recent studies. The objective of this work was a comparative study of the biomechanical properties of the posterolateral plate fixation with retrograde intramedullary nail fixation.MethodsTwenty four fresh-frozen human lower leg specimens (12 pairs) were used for the comparative biomechanical testing. Every specimen was preconditioned with 100 N over 200 cycles. After every 250 cycles the force was increased by 50 N from 200 to 600 N. This was followed by cyclic loading in dorsi-/plantiflexion with 800 N for 3000 cycles. All specimens were subjected to bone densitometry (DXA) and computed tomography.ResultsSignificantly higher number of spacimens with nails (4) failed during the cycling testing in dorsi-/plantarflexion and futher two during the cyclic testing with 800 N. Two specimens with plates failed during the cyclic testing with 800 N. Statistical analysis showed that the specimens with the plate were significantly more stable in each test direction. The Pearson correlation demonstrated for the specimens with plate a linear relationship between the stiffness and the determined bone density.ConclusionsThe results demonstrate a significantly superior stiffness of the Pantalarlock®-plate in all testing directions compared with the HAN nail. Probably the position of the plate on the tension side of the joint and the combination of locking and lag screws provide the higher stiffness of the plate system. The correlation of the stiffness with bone density leads to more predictable results of the plate arthrodesis. We hope for a reduction of the pseudarthrosis rate and shorten the postoperative treatment phase. The authors expect advantages in the treatment of high risk patients with severe deformity of the ankle, bone defects, neuropathic deformity, poor bone quality and osteoporosis.  相似文献   
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