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1.
Activated status of tumour-infiltrating lymphocytes and apoptosis in testicular seminoma. 总被引:6,自引:0,他引:6
Evgeny Yakirevich Oleg Lefel Yanina Sova Avi Stein Oded Cohen Ofer Ben Izhak Murray B Resnick 《The Journal of pathology》2002,196(1):67-75
Testicular seminoma is characterized by a prominent lymphoid infiltrate and an excellent prognosis. Cytotoxic T-lymphocytes (CTLs) infiltrating seminoma tumour nests constitute a major subset of the lymphoid infiltrate. The objective of this study was to determine whether CTLs express markers of cytotoxic potential and activity and whether the number of activated CTLs correlates with the extent of apoptosis in testicular seminomas, as opposed to non-seminomatous testicular germ cell tumours (NSTGCTs). Twenty cases of pure seminoma as well as 20 cases of NSTGCTs including 16 mixed germ cell tumours (MGCTs) were studied. Immunohistochemistry for the cytotoxic markers TIA-1 (cytotoxic potential) and granzyme B (cytotoxic activity) and the T-cell markers CD3 and CD8 was performed on formalin-fixed, paraffin-embedded sections. The apoptotic index (AI) was determined by the TUNEL method. The number of CD3(+), CD8(+), TIA-1(+), and granzyme B(+) cells in tumour cell nests was markedly increased in testicular seminomas, compared with NSTGCTs (p<0.01). Activated granzyme B(+) cells numbered 25.6+/-5.2 per high power field in seminomas and 8.9+/-3.2, 8.1+/-3.9, and 0.4+/-0.2 for embryonal carcinomas, yolk sac tumours, and immature teratomas, respectively. Double immunohistochemical staining for granzyme B and CD8 revealed that 82.6+/-8.5% of granzyme B-expressing cells were CD8(+). The tumour cell AI was significantly increased in embryonal carcinoma, compared with the seminoma, yolk sac tumour, and immature teratoma subgroups (6.7+/-1.3, 2.3+/-0.3, 3.0+/-1.1, and 2.3+/-1.1, respectively, p<0.001). TUNEL/CD3 double immunostaining revealed that a significant proportion of the apoptotic seminomatous tumour cells were in direct contact with one or more CD3(+) lymphocytes (47.2+/-6.2%). The number of activated granzyme B(+) CTLs showed a strong linear correlation with the AI in the seminoma group (r=0.71, p<0.0001) but not in other subgroups. TUNEL/granzyme B double immunolabelling revealed that a proportion of activated granzyme B(+) lymphocytes (20%) were often seen in close contact with apoptotic tumour cells. The presence of increased numbers of activated cytotoxic lymphocytes in testicular seminomas suggests that apoptotic tumour cell death in this neoplasm may be triggered by cytotoxic granule effectors. This phenomenon may be one of the key host immune mechanisms leading to the excellent prognosis in this tumour. 相似文献
2.
Antonov AS Avilov SA Kalinovsky AI Anastyuk SD Dmitrenok PS Evtushenko EV Kalinin VI Smirnov AV Taboada S Ballesteros M Avila C Stonik VA 《Journal of natural products》2008,71(10):1677-1685
Five new triterpene glycosides, liouvillosides A1 (1), A2 (2), A3 (3), B1 (4), and B2 (5), have been isolated from the Antarctic sea cucumber Staurocucumis liouviellei along with the known liouvilloside A(6), isolated earlier from the same species, and hemoiedemosides A (7) and B (8), isolated earlier from the Patagonian sea cucumber Hemioedema spectabilis. The isolation was carried out using a new chromatographic procedure including application of ion-pair reversed-phase chromatography followed by chiral chromatography on a cyclodextrin ChiraDex column. The structures of the new glycosides were elucidated using extensive NMR spectroscopy (1H and 13C NMR spectrometry, DEPT, 1H-(1)H COSY, HMBC, HMQC, and NOESY), ESI-FTMS, and CID MS/MS, and chemical transformations. Glycosides 1-3 are disulfated tetraosides and glycosides 4 and 5 are trisulfated tetraosides. Glycosides 2 and 3 contain 3-O-methylquinovose, found for the first time as a natural monosaccharide in sea cucumber glycosides. On the basis of analyses of glycoside structures a taxonomic revision is proposed. 相似文献
3.
In this work, the method of electron beam additive manufacturing (EBAM) was used to fabricate a Cu-based alloy possessing a shape memory effect. Electron beam additive technology is especially relevant for copper and its alloys since the process is carried out in a vacuum, which makes it possible to circumvent oxidation. The main purpose of the study was to establish the influence of the printing parameters on the structure of the obtained products, their phase composition, mechanical properties, dry friction behavior, and the structure-phase gradient that formed in Cu–Al–Mn alloy samples during electron beam layer-by-layer printing. The results of the study allowed us to reveal that the structure-phase composition, the mechanical properties, and the tribological performance of the fabricated material are mainly affected by the magnitude of heat input during electron beam additive printing of Cu–Al–Mn alloy. High heat input values led to the formation of the β1′ + α decomposed structure. Low heat input values enabled the suppression of decomposition and the formation of an ordered 1 structure. The microhardness values were distributed on a gradient from 2.0 to 2.75 GPa. Fabricated samples demonstrated different behaviors in friction and wear depending on their composition and structure, with the value of the friction coefficient lying in the range between 0.1 and 0.175. 相似文献
4.
Sergei M. Pimenov Evgeny V. Zavedeev Beat Jaeggi Josef Zuercher Beat Neuenschwander 《Materials》2022,15(13)
In the paper, we study the formation of laser-induced periodic surface structures (LIPSS) on diamond-like nanocomposite (DLN) a-C:H:Si:O films during nanoscale ablation processing at low fluences—below the single-pulse graphitization and spallation thresholds—using an IR fs-laser (wavelength 1030 nm, pulse duration 320 fs, pulse repetition rate 100 kHz, scanning beam velocity 0.04–0.08 m/s). The studies are focused on microscopic analysis of the nanostructured DLN film surface at different stages of LIPSS formation and numerical modeling of surface plasmon polaritons in a thin graphitized surface layer. Important findings are concerned with (i) sub-threshold fabrication of high spatial frequency LIPSS (HSFL) and low spatial frequency LIPSS (LSFL) under negligible surface graphitization of hard DLN films, (ii) transition from the HSFL (periods of 140 ± 30 and 230 ± 40 nm) to LSFL (period of 830–900 nm) within a narrow fluence range of 0.21–0.32 J/cm2, (iii) visualization of equi-field lines by ablated nanoparticles at an initial stage of the LIPSS formation, providing proof of larger electric fields in the valleys and weaker fields at the ridges of a growing surface grating, (iv) influence of the thickness of a laser-excited glassy carbon (GC) layer on the period of surface plasmon polaritons excited in a three-layer system “air/GC layer/DLN film”. 相似文献
5.
Igor S. Batraev Vladimir Yu. Ulianitsky Alexey A. Sova Marina N. Samodurova Evgeny A. Trofimov Kirill Yu. Pashkeev Alexander G. Malikov Dina V. Dudina Arina V. Ukhina 《Materials》2022,15(13)
In this work, a new two-stage approach to the deposition of high-entropy alloy coatings is proposed. At the first stage, a composite precursor coating is formed by detonation spraying of the metal powder mixtures. At the second stage, the precursor coating is re-melted by a laser, and the formation of multi-component solid solution phases can be expected upon solidification. The feasibility of the proposed approach was validated using three different mixtures of Fe, Ni, Cu, Co and Al powders. It was shown that detonation spraying allows forming composite coatings with a uniform distribution of the lamellae of different metals. The results of the structural analysis of the laser-treated coatings suggest that complete alloying occurred in the melt and face-centered cubic solid solutions formed in the coatings upon cooling. 相似文献
6.
Evgeny Pavlushkov Nagarajan Muthialu Helen Spencer Clair Ellis Ben Davies Sarah Claydon Marius Berman 《Pediatric transplantation》2019,23(4)
A clinical case of successful procurement and transplantation of bilateral lungs from 6‐week‐old infant with sepsis secondary to bacterial meningitis is reported. Forty‐one‐day‐old male infant (height 60 cm, weight 4 kg) died of cerebral edema secondary to Escherichia coli meningitis and bacteremia. Preretrieval assessment included the following: arterial gases; pO2 50.4 kPa (378 mm Hg), pCO2 4.9 kPa (37 mm Hg), on FiO2 100%, PEEP 5 cm H2O. Fiberoptic bronchoscopy showed no secretions nor mucosal inflammation; CXR revealed clear lung fields and pleural spaces. Inspection revealed dense adhesions in pericardial cavity and purulent left hemithorax effusion (urgent Gram‐stain came back as negative) but there was no consolidation in the lung. Good compliance of the lungs on inflation/deflation test was observed. The lungs were retrieved using the technique described. The recipient was a 4‐month‐old infant with alveolar capillary dysplasia and malaligned pulmonary veins. Implantation of the lungs was performed via bilateral thoracosternotomy on cardiopulmonary bypass, cooling to 30°C. Elective support with nitric oxide was used postoperatively. Two years after the transplantation, the recipient doing well with normal lung function. Lung procurement from a 6‐week donor with infectious complications and prolonged ventilation is a challenging undertaking but can be successful and should be attempted whenever possible given the paucity of organs available for pediatric recipients. 相似文献
7.
Tetiana Kiriazova Karsten Lunze Anita Raj Natalia Bushara Elena Blokhina Evgeny Krupitsky 《AIDS care》2017,29(5):559-563
Many HIV-positive people who inject drugs (PWID) globally are not receiving HIV care. This represents a major challenge among key populations to end the global HIV epidemic. This qualitative study explored the process and associated barriers of linking HIV-positive PWID who are in addiction treatment to HIV care in St. Petersburg, Russia. We conducted three focus groups and seven semi-structured interviews with participants in the LINC (“Linking Infectious and Narcology Care”) project at addiction and HIV hospitals in St. Petersburg. The sample consisted of 25 HIV-infected patients with opioid dependence and seven health-care providers, including addiction and infectious disease physicians and case managers. A variety of intertwining factors influence effective engagement of PWID with HIV treatment. Stigma, problematic patient–provider relationships, and fragmented health care were the main challenges for HIV care initiation by PWID, which were further exacerbated by injection drug use. Effective linkage of PWID to HIV care requires acknowledging and addressing stigma’s role and different perspectives of patients and providers. 相似文献
8.
9.
Reorganization of Lamellar Diblock Copolymer Poly(ε‐caprolactone)‐block‐poly(4‐vinylpyridine) in the Melting Temperature Range 下载免费PDF全文
Lanlan Chen Jing Jiang Evgeny Zhuravlev Lai Wei Christoph Schick Gi Xue Dongshan Zhou 《Macromolecular chemistry and physics.》2015,216(22):2211-2220
The reorganization kinetics of the “original” lamellar diblock copolymer poly(ε‐caprolactone)‐block‐poly(4‐vinylpyridine) crystals formed at 260 K is studied in the melting region from 270 K (10 K below the onset of the melting peak of original crystals) to 310 K (the melting peak temperature) on the time scale starting from 10?4 to 102 s by ultrafast differential scanning calorimetry. Different reorganization pathways are observed in this temperature range. Annealing at temperatures below 295 K leads to further stabilization of original crystals by secondary crystallization. At annealing temperatures higher than 295 K, crystals partially melt and the reorganization occurs via the melting–recrystallization. For even higher temperature, such as 310 K, the melting is completed within a few milliseconds and recrystallization starts from the nuclei formation. The sigmoidal recrystallization kinetics is analyzed by the Avrami equation. It is found that the copolymer experiences about one order of magnitude slower recrystallization rate and has higher melting peak temperatures of crystals formed after recrystallization than the homopolymer. The slower recrystallization kinetics in the copolymer is discussed from the viewpoint of the nanoscale spatial constraint and the intermediate state prior to the recrystallization.
10.
Maria Nadinskaia Marina Maevskaya Vladimir Ivashkin Khava Kodzoeva Irina Pirogova Evgeny Chesnokov Alexander Nersesov Jamilya Kaibullayeva Akzhan Konysbekova Aigul Raissova Feruza Khamrabaeva Elena Zueva 《World journal of gastroenterology : WJG》2021,27(10):959-975
BACKGROUNDAtherosclerotic cardiovascular disease (ASCVD) is the leading cause of mortality in patients with nonalcoholic fatty liver disease (NAFLD). Weight loss is a key factor for successful NAFLD and CVD therapy. Ursodeoxycholic acid (UDCA), which is one of the first-line therapeutic agents for treatment of NAFLD, is reported to have a beneficial effect on dyslipidemia and ASCVD risk because of antioxidant properties.AIMTo evaluate the effects of 6 mo of UDCA treatment on hepatic function tests, lipid profile, hepatic steatosis and fibrosis, atherogenesis, and ASCVD risk in men and women with NAFLD, as well as to assess the impact of > 5% weight reduction on these parameters.METHODSAn open-label, multicenter, international noncomparative trial was carried out at primary health care settings and included 174 patients with ultrasound-diagnosed NAFLD who received 15 mg/kg/d UDCA for 6 mo and were prescribed lifestyle modification with diet and exercise. The efficacy criteria were liver enzymes, lipid profile, fatty liver index (FLI), noninvasive liver fibrosis tests (nonalcoholic fatty liver disease fibrosis score and liver fibrosis index), carotid intima-media thickness (CIMT), and ASCVD risk score. To test statistical hypotheses, the Wilcoxon test, paired t-test, Fisher’s exact test, and Pearson''s chi-squared test were used. RESULTSThe alanine aminotransferase (ALT) level changed by -14.1 U/L (-31.0; -5.3) from baseline to 3 mo and by -6.5 U/L (-14.0; 0.1) from 3 to 6 mo. The magnitude of ALT, aspartate transaminase, and glutamyltransferase decrease was greater during the first 3 mo of treatment compared to the subsequent 3 mo (P < 0.001, P < 0.01, P < 0.001, respectively). At 6 mo, in the total sample, we observed a statistically significant decrease in body weight and levels of FLI: 84.9 ± 10.4 vs 72.3 ± 17.6, P < 0.001, total cholesterol: 6.03 ± 1.36 vs 5.76 ± 1.21, Р < 0.001, low-density lipoprotein: 3.86 ± 1.01 vs 3.66 ± 0.91, Р < 0.001, and triglyceride: 3.18 (2.00; 4.29) vs 2.04 (1.40; 3.16), Р < 0.001. No effect on nonalcoholic fatty liver disease fibrosis score or liver fibrosis index was found. The CIMT decreased significantly in the total sample (0.985 ± 0.243 vs 0.968 ± 0.237, P = 0.013), whereas the high-density lipoprotein (Р = 0.036) and 10-year ASCVD risk (Р = 0.003) improved significantly only in women. Fifty-four patients (31%) achieved > 5% weight loss. At the end of the study, the FLI decreased significantly in patients with (88.3 ± 10.2 vs 71.4 ± 19.6, P < 0.001) and without > 5% weight loss (83.5 ± 10.3 vs 72.8 ± 16.7, P < 0.001). The changes in ALT, aspartate transaminase, glutamyltransferase, total cholesterol, and low-density lipoprotein levels were similar between the subgroups.CONCLUSIONUDCA normalizes liver enzymes greatly within the first 3 mo of treatment, improves lipid profile and hepatic steatosis independent of weight loss, and has a positive effect on CIMT in the total sample and 10-year ASCVD risk in women after 6 mo of treatment. 相似文献