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1.
The cytotoxic host immune response toward autologous human cancer may be regulated by the immunoregulatory network. Here we show that helper T cells, cloned from peripheral blood lymphocytes that were sensitized in vitro against an autologous human malignant paraganglioma, proliferated against and made interleukin 2 when cocultured with the tumor-associated antigen in the presence of autologous accessory cells. Furthermore, the helper cell clones amplified cytotoxic immune response by peripheral blood lymphocytes against the paraganglioma cells in coculture with the blood lymphocytes and the paraganglioma cells. An autologous T cell line bearing suppressor phenotype, established from a lymph node that had been infiltrated with the paraganglioma tumor cells, in contrast to the helper cells, selectively suppressed the cytotoxic immune response by the blood lymphocytes against the paraganglioma cells in identical coculture. These results, therefore, demonstrate the existence of cell-mediated immunologic regulations of the cytotoxic immune response (concurrent amplification and suppression in the same host) against an autologous human tumor.  相似文献   
2.
The potential existence of down-regulation of cytotoxic immune response against an autologous human melanoma line was investigated as a possible explanation for cytotoxic unresponsiveness against the autologous melanoma cells. The melanoma cell line, PJ-M, was established and lymph node resident lymphocytes (LNL) were isolated from a lymph node which was partially infiltrated with the melanoma cells. Autologous peripheral blood lymphocytes (PBL) were sensitized in in vitro co-culture (IVC) against radiated PJ-M cells in the presence or absence of PJ-M-sensitized LNL and enriched suppressor (OKT8+) or inducer (OKT4+) LNL populations, and were assayed for cytotoxicity in a 4-hr 51Cr-release microcytotoxicity assay. Significant cytotoxic response against PJ-M could be generated in the PBL, but not in the LNL. The addition of sensitized, unfractionated LNL, OKT8+, or OKT4+ LNL populations abrogated cytotoxic response in the PBL against PJ-M. The suppression of cytotoxic response was induced selectively against the PJ-M targets, because IVC of PBL in the presence of the sensitized LNL did not affect the generation of polyclonal cytotoxic alloreactivities, nor did they abrogate the generation of cytotoxic response against allogeneic targets in IVC against the corresponding allogeneic targets. These results suggest the possibility that cytotoxic immune response against the autologous melanoma cells might have been suppressed by the individual's own immunoregulatory circuit.  相似文献   
3.
A clinical trial of adoptive immunotherapy was carried out with peripheral blood lymphocytes (PBL), cocultured in vitro with autologous tumor cells and interieukin-2 (IL-2), in 14 patients with advanced melanoma. PBL from these patients were cocultured with irradiated autologous tumor cells for 7 days, which was followed by expansion in IL-2-containing medium. These lymphocytes were returned to the patient along with intravenous IL-2 at doses up to 2×106 IU m–2 day–1. A dose of 300 mg/m2 cyclophosphamide was administered to each patient intravenously 4 days prior to each treatment. Following coculture, the lymphocytes were primarily CD3+ T cells and they expressed varied degrees of cytotoxicity against autologous melanoma cells. In 9 patients the activated cells were al least 80% CD4+ and in 2 cases they were mostly CD8+. Some of the activated cells exhibited suppressor or helper activity in a functional regulatory coculture assay. No major therapeutic response was observed in this study. Minor responses were observed in 2 patients. Toxicities were those expected from the IL-2 dose administered.This work has been supported by an American Cancer Society Institutional Research Grant (ACS-IRG 91-230), by the University of Connecticut Clinical Research Center (grant 0021), and by the Hartford Hospital Research Fund (grant 1017-20-018). Dr. Sporn is a recipient of American Cancer Society Clinical Oncology Career Development Award 90-230  相似文献   
4.
Helichrysum Mill. (Asteraceae) species have been used in folk medicine for thousands of years in the world. The in vitro cytogenetic effects in human lymphocytes of nine Helichrysum taxa used in Turkey folk medicine were investigated. Blood samples were obtained from healthy donors, non-smoking volunteers, which were incubated and exposed to increasing concentrations of methanol extracts of Helichrysum taxa (0.01, 0.05, 0.1, 0.5 and 1 mg/mL). The inhibitory effects of H. stoechas (L.) Moench subsp. barrelieri (Ten.) Nyman, H. armenium DC. subsp. armenium, H. armenium DC. subsp. araxinum (Kirp.) Takht., H. plicatum DC. subsp. plicatum, H. compactum Boiss. and H. artvinense P.H.Davis & Kupicha on the mitotic index and replication index indicate that these taxa can have genotoxic and mutagenic effects. They should therefore not be used freely in alternative medicine although their antiproliferative activity may suggest anticarcinogenic properties. Increase effects of H. stoechas subsp. barrelieri, H. armenium subsp. armenium, H. armenium subsp. araxinum, H. chasmolycicum P.H.Davis, H. plicatum subsp. plicatum, H. compactum and H. artvinense on the micronucleus rates showed that these taxa can have genotoxic and carcinogenic effects.  相似文献   
5.
Karyotypic characters, mitotic metaphase chromosomes, monoploid idiograms and karyograms of Minuartia anatolica (Boiss.) Woronow var. phrygia (Bornm.) McNeill, Minuartia anatolica (Boiss.) Woronow var. scleranthoides (Boiss. & Noe) McNeill, Minuartia corymbulosa (Boiss. & Balansa) McNeill var. gypsophilloides McNeill and Minuartia aksoyi M.Koç & Hamzao?lu were investigated for the first time. Analysis of somatic metaphases showed that the chromosome numbers and the formulas of these taxa were 2n = 24 = 14m + 6sm + 4st for Minuartia anatolica var. phrygia, 2n = 14 = 6m + 8sm for Minuartia anatolica var. scleranthoides, 2n = 14 = 6m + 4sm + 4st for Minuartia corymbulosa var. gypsophilloides and 2n = 30 = 14m + 10sm + 6st for Minuartia aksoyi. No satellites were observed in the karyotypes of these taxa. Karyotype asymmetry was estimated by many different methods, namely the Stebbins classification, the karyotype asymmetry index (As K %), the total form percent (TF %), the Rec and Syi indices, the intrachromosomal asymmetry index (A1) and interchromosomal asymmetry index (A2), the dispersion index (DI), the degree of asymmetry of karyotype (A index) and the asymmetry index (AI).  相似文献   
6.
Galatella anatolica Hamzao?lu & Budak sp. nov. (Asteraceae), collected from Osmaniye (Turkey) is here described as a new species. It is similar to G. angustissima (Tausch) Novopokr. in general habit. Both have stems with few branches and 1‐veined middle leaves, but are distinguished by involucral features, series of phyllaries, and lengths of disc florets, achenes and pappus.  相似文献   
7.
This paper summarizes results from two large lung cancer studies comprising over 700 samples that demonstrate the ability of spectral histopathology (SHP) to distinguish cancerous tissue regions from normal tissue, to differentiate benign lesions from normal tissue and cancerous lesions, and to classify lung cancer types. Furthermore, malignancy‐associated changes can be identified in cancer‐adjacent normal tissue. The ability to differentiate a multitude of normal cells and tissue types allow SHP to identify tumor margins and immune cell infiltration. Finally, SHP easily distinguishes small cell lung cancer (SCLC) from non‐SCLC (NSCLC) and provides a further differentiation of NSCLC into adenocarcinomas and squamous cell carcinomas with an accuracy comparable of classical histopathology combined with immunohistochemistry. Case studies are presented that demonstrates that SHP can resolve interobserver discrepancies in standard histopathology.  相似文献   
8.
In Vitro Cellular & Developmental Biology - Plant - A rapid and efficient in vitro micropropagation system was developed to conserve Tripleurospermum fissurale (Sosn.) E.Hossain (Asteraceae), a...  相似文献   
9.
Most nonsyndromic hearing losses are caused by mutations in the GJB2 gene, and studies have revealed that the forms and frequencies of these mutations are largely dependent on ethnic origin. In the present study, we aimed to characterize the mutation profiles of 151 patients with hearing loss in Turkey. The entire coding region of the GJB2 was directly sequenced in all patients. We found 35 (23.2%) individuals carrying GJB2 mutations. Seven different mutations were identified, five of which were previously known (35delG, delE120, R184P, M163V, L90P), the remaining two being novel variants (M34V, L205V). The most common mutation was 35delG followed by delE120. The 35delG mutation was homozygous in 22 cases (14.5%) and heterozygous in 4 cases (2.6%). Compound heterozygosity for 35delG was also observed. The delE120 mutation was found in three patients in homozygous form. A homozygous L90P and heterozygous mutations M163V and M34V were found in single cases.  相似文献   
10.
Coenzyme Q10 is an important component of mitochondrial electron transport chain and antioxidant. Hyperthyroidism manifests hyperdynamic circulation with increased cardiac output, increased heart rate and decreased peripheral resistance. The heart is also under the oxidative stress in the hyperthyroidism. The aim of this study was to examine both how the coenzyme Q10 can affect heart ultrastructure in the hyperthyroidism and how the relationship between nitric oxide synthase (NOS) and heart damage and coenzyme Q10. Swiss Black C57 mice received 5 mg/kg L-thyroxine. Coenzyme Q10 (1.5 mg/kg) and L-thyroxine together was given to second group mice. Coenzyme Q10 and serum physiologic were applied to another two groups, respectively. All treatments were performed daily for 15 days by gavage. Free triiodothyronine and thyroxine were increased in two groups given L-thyroxine; thyroid-stimulating hormone level did not change. Hyperthyroid heart showed an increased endothelial NOS (eNOS) and inducible NOS (iNOS) immunoreactivity in the tissue. Coenzyme Q10 administration decreased these NOS immunoreactivities in the hyperthyroid animals. Cardiomyocytes of the hyperthyroid animals was characterized by abnormal shape and invaginated nuclei, and degenerative giant mitochondria. Desmosome plaques reduced in density. In hyperthyroid mice given coenzyme Q10, the structural disorganization and mitochondrial damage regressed. However, hearts of healthy mice given coenzyme Q10 displayed normal ultrastructure, except for increased mitochondria and some of them were partially damaged. Coenzyme Q10 increased the glycogen in the cardiomyocytes. In conclusion, coenzyme Q10 administration can prevent the ultrastructural disorganization and decrease the iNOS and eNOS increment in the hyperthyroid heart.  相似文献   
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