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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.
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
3.
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
4.
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
5.
Karim Ravilevich Muratov Timur Rizovich Ablyaz Evgeny Anatolevich Gashev Irina Georgievna Goryacheva 《Materials》2022,15(9)
The regularities of the formation of the resulting raster tool trajectories based on Lissajous figures for the lapping process of planes are established. This makes it possible to maximize the cutting ability of the tool, which contributes to its more uniform wear and increased productivity and processing quality. Optimal parameters of productivity and roughness of the treated surface during lapping of zirconium ceramics are achieved through the use of ASM paste 28/20 µm. Based on Preston’s hypothesis, an exponential dependence of the change in the contact area during the lapping of planes of different initial shape of the macrorelief is obtained. The obtained theoretical and practical results of the study of the process of flat lapping with constant and variable clamping force of the treated surface to the surface of the tool. The influence of the force factor on the formation of the surface in the process of abrasive lapping has been established. Studies have been carried out and the main technological recommendations of precision surface treatment of workpieces based on hard, brittle ceramic material and bronze samples on equipment with a raster trajectory of the tool movement are presented. The optimal pressure value when processing ceramics should be considered 203–270 kPa (2.1–2.8 kg/cm2). 相似文献
6.
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
7.
8.
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.
9.
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
10.
E Dillwyn Williams Alexander Abrosimov Tatiana Bogdanova Evgeny P Demidchik Masahiro Ito Virginia LiVolsi Evgeny Lushnikov Juan Rosai Mikola D Tronko Anatoly F Tsyb Sarah L Vowler Geraldine A Thomas 《Thyroid》2008,18(8):847-852
BACKGROUND: The Chernobyl accident caused an unprecedented increase in papillary thyroid carcinoma (PTC) incidence with a surprisingly short latency and unusual morphology. We have investigated whether unexpected features of the PTC incidence after Chernobyl were radiation specific or influenced by iodine deficiency. METHODS: PTCs from children from Belarus, Ukraine, and the Russian Federation exposed to fallout from Chernobyl were compared with PTCs from children not exposed to radiation from the same countries, from England and Wales (E&W) and from Japan. The degree and type of differentiation, fibrosis, and invasion were quantified. RESULTS: There were no significant differences between PTCs from radiation-exposed children from Belarus, Ukraine, and the Russian Federation and PTCs from children from the same countries who were not exposed to radiation. Childhood PTCs from Japan were much more highly differentiated (p < 0.001), showed more papillary differentiation (p < 0.001) and were less invasive (p < 0.01) than "Chernobyl" tumors, while tumors from E&W generally showed intermediate levels of degree and type of differentiation and invasion. There was a marked difference between the sex ratios of children with PTCs who were radiation exposed and those who were not exposed (F:M exposed vs. unexposed 1.5:1 vs. 4.2:1; chi(2) = 7.90, p < or = 0.01005). CONCLUSIONS: The aggressiveness and morphological features of Chernobyl childhood PTCs are not associated with radiation exposure. The differences found between tumors from the Chernobyl area, E&W, and Japan could be influenced by many factors. We speculate that dietary iodine levels may have wide implications in radiation-induced thyroid carcinogenesis, and that iodine deficiency could increase incidence, reduce latency, and influence tumor morphology and aggressiveness. 相似文献