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31.
32.
In many organisms completion of the first meiotic cell division depends on the correct assembly and disassembly of the synaptonemal
complex (SC). This is a structure discovered a little over 50 years ago, which is formed by the close association of axes
of homologous sister chromatid pairs. Its structure varies between organisms, although it retains a common tripartite organization
in species as evolutionarily distant as budding yeast and humans. In mammals it is essential for crossover formation and completion
of meiosis. Components of the mammalian SC have been identified only in the last 15 years, and mouse genetic approaches have
started revealing the importance for this structure only in the past 5 years. Here we discuss the progress that has been made
in the field of the mammalian SC and what approaches could be considered for its further study. 相似文献
33.
Stephen F Stanziale Henrik Petrowsky Prasad S Adusumilli Leah Ben-Porat Mithat Gonen Yuman Fong 《Clinical cancer research》2004,10(9):3225-3232
PURPOSE: The antitumor efficacy of a herpes simplex virus (HSV)-1 oncolytic virus depends on the cytotoxic effect of the virus, but also on viral replication and spread within the tumor. Apoptosis is considered a defense mechanism of infected cells that minimizes the spread of viral progeny by limiting cellular production of virus. We sought to determine whether oncolytic HSV-1 infection induces apoptosis in neighboring, uninfected cells and whether manipulation of apoptosis can increase viral replication and cytotoxicity. EXPERIMENTAL DESIGN: NV1066 is an oncolytic HSV-1 mutant that contains the marker gene for enhanced green fluorescent protein. OCUM human gastric cancer cells were infected with NV1066 in vitro and inspected for apoptosis by Hoechst and terminal deoxynucleotidyltransferase-mediated nick end labeling staining and for infection by expression of green fluorescence. RESULTS: A significant increase in apoptosis was seen in cells infected by NV1066. More interestingly, a significant percentage (10%) of uninfected cells also proceeded to apoptosis. After NV1066 infection, cells were also treated with N-acetylcysteine (NAC), an inhibitor of apoptosis. By day 4 after infection, 2.7x more NV1066 was produced in cells exposed to NAC than in those not exposed to NV1066 (P = 0.04). NAC also increased tumor kill when administered with virus. CONCLUSIONS: These data suggest that NV1066 induces apoptosis in uninfected cocultured cells, potentially hindering propagation of viral progeny and concomitant tumor kill. Inhibition of apoptosis may improve the efficacy of oncolytic HSV-1 therapy. 相似文献
34.
35.
Whole body 18FDG-PET and the response of esophageal cancer to induction therapy: results of a prospective trial. 总被引:13,自引:0,他引:13
Robert J Downey Tim Akhurst David Ilson Robert Ginsberg Manjit S Bains Mithat Gonen Heng Koong Marc Gollub Bruce D Minsky Maureen Zakowski Alan Turnbull Steven M Larson Valerie Rusch 《Journal of clinical oncology》2003,21(3):428-432
PURPOSE: Whole-body 18F-fluorodeoxyglucose ([18F]FDG) positron emission tomography (PET) imaging before and after induction therapy was prospectively evaluated in patients with esophageal cancer to determine whether changes in PET images could measure response to therapy. PATIENTS AND METHODS: Between April 1997 and April 1999, 39 patients (34 men and five women; median age, 59 years; range, 36 to 76 years) with esophageal cancer were prospectively enrolled in a single-institution clinical trial of staging, including PET, induction therapy, restaging including PET, and esophagectomy. All patients undergoing esophagectomy after induction therapy (n = 17) were followed either to recurrence, to death, or through a disease-free interval of at least 24 months. RESULTS: PET after standard staging studies and before therapy imaged undetected sites of metastatic disease in six patients (15%). Restaging (including PET) after induction therapy did not identify any patients with disease progression or any patients with loco-regionally unresectable disease at exploration. The median decrease in the standardized uptake value (SUV) during induction therapy was 59%. After R0 esophagectomy, the 2-year disease-free and overall survival was 38% and 63%, respectively, among patients who had a less than 60% decrease in SUV, and 67% and 89%, respectively, among patients who had a greater than 60% decrease in SUV (P =.055 and P =.088, respectively). CONCLUSION: Compared with conventional imaging, PET detects additional sites of metastatic disease at initial evaluation. After induction therapy, PET did not add to the estimation of loco-regional resectability and did not detect new distant metastases. However, changes in [18F]FDG PET may predict disease-free and overall survival after induction therapy and resection in patients with esophageal cancer. Further evaluation in larger trials is warranted. 相似文献
36.
Cancer-testis genes are coordinately expressed and are markers of poor outcome in non-small cell lung cancer. 总被引:5,自引:0,他引:5
Ali O Gure Ramon Chua Barbara Williamson Mithat Gonen Cathy A Ferrera Sacha Gnjatic Gerd Ritter Andrew J G Simpson Yao-T Chen Lloyd J Old Nasser K Altorki 《Clinical cancer research》2005,11(22):8055-8062
PURPOSE: Cancer-testis genes mapping to the X chromosome have common expression patterns and show similar responses to modulators of epigenetic mechanisms. We asked whether cancer-testis gene expression occurred coordinately, and whether it correlated with variables of disease and clinical outcome of non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: Tumors from 523 NSCLC patients undergoing surgery were evaluated for the expression of nine cancer-testis genes (NY-ESO-1, LAGE-1, MAGE-A1, MAGE-A3, MAGE-A4, MAGE-A10, CT7/MAGE-C1, SSX2, and SSX4) by semiquantitative PCR. Clinical data available for 447 patients were used to correlate cancer-testis expression to variables of disease and clinical outcome. RESULTS: At least one cancer-testis gene was expressed by 90% of squamous carcinoma, 62% of bronchioloalveolar cancer, and 67% of adenocarcinoma samples. Statistically significant coexpression was observed for 34 of the 36 possible cancer-testis combinations. Cancer-testis gene expression, either cumulatively or individually, showed significant associations with male sex, smoking history, advanced tumor, nodal and pathologic stages, pleural invasion, and the absence of ground glass opacity. Cox regression analysis revealed the expression of NY-ESO-1 and MAGE-A3 as markers of poor prognosis, independent of confounding variables for adenocarcinoma of the lung. CONCLUSIONS: Cancer-testis genes are coordinately expressed in NSCLC, and their expression is associated with advanced disease and poor outcome. 相似文献
37.
Quercetin alters the DNA damage response in human hematopoietic stem and progenitor cells via TopoII‐ and PI3K‐dependent mechanisms synergizing in leukemogenic rearrangements
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Melanie Rall Nasma Aqaqe Muhammad Yassin Adi Zipin‐Roitman Luba Trakhtenbrot Leonid Olender Yael Raz Ariel J. Jaffa Dan Grisaru Lisa Wiesmuller David Elad Michael Milyavsky 《International journal of cancer. Journal international du cancer》2017,140(4):864-876
Quercetin (Que) is an abundant flavonoid in the human diet and high‐concentration food supplement with reported pro‐ and anti‐carcinogenic activities. Topoisomerase II (TopoII) inhibition and subsequent DNA damage induction by Que was implicated in the mixed lineage leukemia gene (MLL) rearrangements that can induce infant and adult leukemias. This notion raised concerns regarding possible genotoxicities of Que in hematopoietic stem and progenitor cells (HSPCs). However, molecular targets mediating Que effects on DNA repair relevant to MLL translocations have not been defined. In this study we describe novel and potentially genotoxic Que activities in suppressing non‐homologous end joining and homologous recombination pathways downstream of MLL cleavage. Using pharmacological dissection of DNA‐PK, ATM and PI3K signalling we defined PI3K inhibition by Que with a concomitant decrease in the abundance of key DNA repair genes to be responsible for DNA repair inhibition. Evidence for the downstream TopoII‐independent mutagenic potential of Que was obtained by documenting further increased frequencies of MLL rearrangements in human HSPCs concomitantly treated with Etoposide and Que versus single treatments. Importantly, by engaging a tissue engineered placental barrier, we have established the extent of Que transplacental transfer and hence provided the evidence for Que reaching fetal HSPCs. Thus, Que exhibits genotoxic effects in human HSPCs via different mechanisms when applied continuously and at high concentrations. In light of the demonstrated Que transfer to the fetal compartment our findings are key to understanding the mechanisms underlying infant leukemia and provide molecular markers for the development of safety values. 相似文献
38.
Ali Eray Günay Ibrahim Karaman Ahmet Guney Zehra Filiz Karaman Eren Demirpolat Zeynep Burcin Gonen Serap Dogan Mukerrem Betul Yerer 《Medicine》2022,101(37)
The aim of the present study was to perform clinical, biochemical, and radiological evaluation of the efficacy of mesenchymal stem cells derived from Wharton jelly (WJ) present within the human umbilical cord in the treatment of knee osteoarthritis. Between 2018 and 2019, 10 patients with knee osteoarthritis for whom the conservative treatment was not beneficial were included in the study. Patients were clinically, radiologically, and biochemically evaluated before treatment initiation. Thereafter, the patients were intra-articularly injected using a solution containing 1 × 108 WJ-derived MSCs. Evaluations were performed on day 21 (V1) and 42 (V2) and month 3 (V3), 6 (V4), and 12 (V5) after the procedure. At 1-year post-injection, visual analogue scale, Western Ontario and McMaster Universities Osteoarthritis Index, and Lequesne scores of patients were lower than those observed during the initial evaluation, whereas the mean 36-Item Short Form Health Survey score was higher. Cartilage thicknesses were found to be increased in all regions except in the medial femur, medial posterior femur, lateral posterior femur, and lateral posterior tibia regions in magnetic resonance imaging. A significant increase was observed in tumor necrosis factor-alpha, interleukin-1β, adiponectin, resistin, and interleukin-6 levels compared with pre-injection values. The leptin levels at 6-month and 1-year controls were lower than the pre-injection levels, and the decrease observed at 6 months was significant. In patients with knee osteoarthritis, intra-articular WJ-derived MSC injection causes significant pain reduction, satisfactory functional improvement, and increased patient satisfaction following a 1-year follow-up. These clinical improvements were supported by magnetic resonance images, along with changes in adiponectin and leptin levels in synovial fluid.Level of evidence: IV. 相似文献
39.
Noam Barda Michal Canetti Mayan Gilboa Victoria Indenboim Keren Asraf Yael Weiss-Ottolenghi Sharon Amit Daniel Zibly Ram Doolman Ella Mendelson Dror Harats Laurence S. Freedman Yitshak Kreiss Yaniv Lustig Gili Regev-Yochay 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(39)
We assess the immunogenicity and efficacy of Spikevax and Comirnaty as fourth dose COVID-19 vaccines. Six months post-fourth-dose, IgG levels were higher than pre-fourth dose at 1.58-fold (95% CI: 1.27–1.97) in Spikevax and 1.16-fold (95% CI: 0.98–1.37) in Comirnaty vaccinees. Nearly 60% (159/274) of vaccinees contracted SARS-CoV-2. Infection hazard ratios (HRs) for Spikevax (0.82; 95% CI: 0.62–1.09) and Comirnaty (0.86; 95% CI: 0.65–1.13) vaccinees were similar, as were substantial-disease HRs, i.e. 0.28 (95% CI: 0.13–0.62) and 0.51 (95% CI: 0.27–0.96), respectively. 相似文献
40.
Gokcen Gonen MD Semra Ulusoy Kaymak MD Eylem Sahin Cankurtaran MD Ersin Hatice Karslioglu MD Elvan Ozalp MD Haldun Soygur MD PhD 《Journal of psychosocial oncology》2013,31(3):347-358
Suffering comes in many ways for patients confronting cancer. One of these is an unspecifiable fear about death, which is an existential issue. The aim of this study was to investigate the relationship between death anxiety and its correlates in cancer patients. Seventy cancer patients were assessed using SCID-I, Templer's Death Anxiety Scale, the Hospital Anxiety (A) and Depression (D) Scale, the Distress Thermometer, the Visual Analogue Scale for pain (VAS), the Global Assessment of Functioning, and Glock and Stark's Dimensions of Religious Commitment scales, and these assessments were compared between cancer patients with and without death anxiety. Multiple regression analysis was conducted after correlation analysis between death anxiety and sociodemographic and clinical variables. Axis I psychiatric diagnosis, pain scores, and negative believes about what will happen after death were found to be higher in patients having death anxiety than patients not having death anxiety. Also life expectancy was perceived as shortened in patients with death anxiety. Death anxiety was associated with anxiety, depressive symptoms, and beliefs about what will happen after death. In conclusion, death anxiety could not be regarded as a natural consequence of having cancer; it is associated with the unresolved psychological and physical distress. 相似文献