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22.
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
23.
Dependence of cross-bridge kinetics on myosin light chain isoforms in rabbit and rat skeletal muscle fibres 总被引:4,自引:1,他引:4
Oleg Andruchov Olena Andruchova Yishu Wang Stefan Galler 《The Journal of physiology》2006,571(1):231-242
Cross-bridge kinetics underlying stretch-induced force transients was studied in fibres with different myosin light chain (MLC) isoforms from skeletal muscles of rabbit and rat. The force transients were induced by stepwise stretches (< 0.3% of fibre length) applied on maximally Ca2+ -activated skinned fibres. Fast fibre types IIB, IID (or IIX) and IIA and the slow fibre type I containing the myosin heavy chain isoforms MHC-IIb, MHC-IId (or MHC-IIx), MHC-IIa and MHC-I, respectively, were investigated. The MLC isoform content varied within fibre types. Fast fibre types contained the fast regulatory MLC isoform MLC2f and different proportions of the fast alkali MLC isoforms MLC1f and MLC3f. Type I fibres contained the slow regulatory MLC isoform MLC2s and the slow alkali MLC isoform MLC1s. Slow MLC isoforms were also present in several type IIA fibres. The kinetics of force transients differed by a factor of about 30 between fibre types (order from fastest to slowest kinetics: IIB > IID > IIA ≫ I). The kinetics of the force transients was not dependent on the relative content of MLC1f and MLC3f. Type IIA fibres containing fast and slow MLC isoforms were about 1.2 times slower than type IIA fibres containing only fast MLC isoforms. We conclude that while the cross-bridge kinetics is mainly determined by the MHC isoforms present, it is affected by fast and slow MLC isoforms but not by the relative content of MLC1f and MLC3f. Thus, the physiological role of fast and slow MLC isoforms in type IIA fibres is a fine-tuning of the cross-bridge kinetics. 相似文献
24.
Guerkov RE Targoni OS Kreher CR Boehm BO Herrera MT Tary-Lehmann M Lehmann PV Schwander SK 《Journal of immunological methods》2003,279(1-2):111-121
Single-cell resolution cytokine ELISPOT assays are increasingly used to gain insights into clonal sizes of type 1 and type 2 effector T cell populations in vivo. However, ELISPOT assays permitting monitoring of regulatory IL-10-producing T cells have so far not been established. Unlike IFN-gamma, IL-2, IL-4, and IL-5 assays performed on PBMC in which the recall antigen-induced cytokine spots are T cell-derived, we show here that in such assays IL-10 is primarily monocyte-derived. T cell-derived IL-10 spots were 80 x 10(3) microm(2) in size, seven times larger than spots produced by monocytes, and B cells produced even smaller spots. Based on spot size gating and the use of B cells as APC, we have established test conditions that permit measurement of cognate IL-10 production by low-frequency antigen-specific T cells. IL-10-producing PPD-specific CD4(+) T cells were detected in frequencies comparable to IFN-gamma-secreting CD4(+) T cells in tuberculosis patients, but not in uninfected healthy control individuals. In contrast, IL-10-secreting CD4(+) T cells specific for a panel of recall antigens could not be detected in frequencies >1/100,000 in healthy individuals whose CD4(+) cells responded to these antigens with type 1 or type 2 cytokine production in the 1:100,000-1:1000 frequency range. Therefore, the induction of IL-10-producing T cells seems to be under tighter control than that of Th1/Th2 cells, apparently confined to states of chronic immune stimulation. Access to low-frequency immune monitoring of IL-10-producing T cells will provide new insights into the role of regulatory T cells in health and disease. 相似文献
25.
Almost all surgical repair techniques for hypospadias include dissection of the glans penis, and covering the neo-urethra with the glans tissue circumferentially. Surprisingly, the presence of the “septum glandis” in the ventral midline has been overlooked for decades. A careful examination of six patients with iatrogenic hypospadias (IH) revealed direct indications of the septum glandis. All patients were treated with long-term urethral catheterisation in the paediatric intensive care unit due to neurologic and/or metabolic diseases. The glans was disrupted in all patients due to ventral midline compression of the urethral catheter, which resulted in a tear in the septum glandis. A remnant of the septum glandis was clearly observed in patients with an incomplete tear. Further injuries caused tear in the frenulum and corpus spongiosum, exposed the glanular urethra and made its vertical elliptical shape, the “fossa navicularis”, visible. Intact contours of the separated glans wings were observed in all patients. The glans wings merge ventrally in the midline, but are separated by a fine connective tissue (septum glandis) in conjunction with the frenulum, which is involved in the formation of the ventral wall of the glanular urethra. IH provides further insight into the structural anatomy of the normal human glans and glanular urethra. 相似文献
26.
Giuliante Felice Viganò Luca De Rose Agostino M. Mirza Darius F. Lapointe Réal Kaiser Gernot Barroso Eduardo Ferrero Alessandro Isoniemi Helena Lopez-Ben Santiago Popescu Irinel Ouellet Jean-Francois Hubert Catherine Regimbeau Jean-Marc Lin Jen-Kou Skipenko Oleg G. Ardito Francesco Adam René 《Annals of surgical oncology》2021,28(13):8198-8208
Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to... 相似文献
27.
Rachel Wuerstlein Nadia Harbeck Eva-Maria Grischke Dirk Forstmeyer Raquel von Schumann Petra Krabisch Kerstin Lüdtke-Heckenkamp Andrea Stefek Oliver Stoetzer Andrea Grafe Gabriele Kaltenecker Helmut Forstbauer Doris Augustin Iris Schrader Joke Tio Ulrike Nitz Oleg Gluz Ronald E. Kates Monika Karla Graeser 《Breast care (Basel, Switzerland)》2021,16(1):50
BackgroundProtroca evaluated the efficacy and safety of primary and secondary prophylaxis of neutropenia with lipegfilgrastim (Lonquex®) in breast cancer patients receiving neoadjuvant or adjuvant chemotherapy (CT).Patients and MethodsOf the 255 patients enrolled, 248 patients were evaluable for the intent-to-treat (ITT) and 194 patients for the per-protocol set. Primary and secondary end points after lipegfilgrastim treatment were assessed.ResultsNine patients of the ITT set receiving lipegfilgrastim as primary prophylaxis (n = 222) had febrile neutropenia of grade 3–4 (5 patients) or infection of grade 3–4 (4 patients); 1/26 of those receiving secondary prophylaxis had an event. Dose reductions were performed in 9.5% of the patients. Postponement of cancer CT cycles for >3 days occurred in <15% of patients; 10.8% (92/851 AEs) and 8% (2/25 SAEs) of documented adverse events and serious adverse events, respectively, were related to lipegfilgrastim.ConclusionsApplication of lipegfilgrastim was effective as primary and secondary prophylaxis in the prevention of CT-induced neutropenia in breast cancer. 相似文献
28.
Anja Ulmer Oleg Schmidt-Kittler J?rg Fischer Ulf Ellwanger Gernot Rassner Gert Riethmüller Gerhard Fierlbeck Christoph A Klein 《Clinical cancer research》2004,10(2):531-537
PURPOSE: The finding of melanoma cells in the peripheral blood, thus far mainly inferred from the PCR-based demonstration of tyrosinase mRNA, has been associated with metastatic melanoma. Neither the malignant nature nor the prognostic significance of circulating cells could be established. To address this question, we analyzed immunomagnetically isolated circulating melanoma cells for chromosomal aberrations and performed a clinical follow-up study of the enrolled patients. EXPERIMENTAL DESIGN: In a prospective study, blood samples were taken from 164 melanoma patients and 50 donors without malignant disease. Circulating melanoma cells were enriched by immunomagnetic cell sorting using a murine monoclonal antibody against the melanoma-associated chondroitin sulfate proteoglycan. To prove the malignant origin of the positive cells and to define their chromosomal aberrations, we analyzed the genomes of 15 individually isolated cells from seven patients by single-cell comparative genomic hybridization (SCOMP). RESULTS: Absolute and relative frequencies of circulating melanoma cells were associated with stage and with the presence or absence of detectable tumor. The detection of two or more cells correlated significantly with a reduced survival of patients with metastatic melanoma. All of the cells that were analyzed by SCOMP displayed multiple chromosomal changes and carried aberrations typical for melanoma. CONCLUSIONS: Immunomagnetic enrichment enables isolation and genomic characterization of circulating melanoma cells. The prognostic impact on survival of metastatic patients apparently reflects the aggressiveness of an ongoing tumor spread. Direct genomic analysis of the enriched and isolated cells will help to clarify the molecular-genetic basis of the establishment of generalized melanoma. 相似文献
29.
30.
Aleksandr M. Filimonov Oleg A. Rogozin Denis G. Firsov Yulia O. Kuzminova Semen N. Sergeev Alexander P. Zhilyaev Marat I. Lerner Nikita E. Toropkov Alexey P. Simonov Ivan I. Binkov Ilya V. Okulov Iskander S. Akhatov Stanislav A. Evlashin 《Materials》2021,14(1)
The particle size distribution significantly affects the material properties of the additively manufactured parts. In this work, the influence of bimodal powder containing nano- and micro-scale particles on microstructure and materials properties is studied. Moreover, to study the effect of the protective atmosphere, the test samples were additively manufactured from 316L stainless steel powder in argon and nitrogen. The samples fabricated from the bimodal powder demonstrate a finer subgrain structure, regardless of protective atmospheres and an increase in the Vickers microhardness, which is in accordance with the Hall-Petch relation. The porosity analysis revealed the deterioration in the quality of as-built parts due to the poor powder flowability. The surface roughness of fabricated samples was the same regardless of the powder feedstock materials used and protective atmospheres. The results suggest that the improvement of mechanical properties is achieved by adding a nano-dispersed fraction, which dramatically increases the total surface area, thereby contributing to the nitrogen absorption by the material. 相似文献