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91.
The aim of this study was to survey the present status and patterns of reirradiation (Re-RT) practice using external beam radiotherapy in Japan. We distributed an e-mail questionnaire to the Japanese Society for Radiation Oncology partner institutions, which consisted of part 1 (number of Re-RT cases in 2008–2012 and 2013–2018) and part 2 (indications and treatment planning for Re-RT and eight case scenarios). Of the 85 institutions that replied to part 1, 75 (88%) performed Re-RTs. However, 59 of these 75 institutions (79%) reported difficulty in obtaining Re-RT case information from their databases. The responses from 37 institutions included the number of Re-RT cases, which totaled 508 in the period from 2009 to 2013 (institution median 3; 0–235), and an increase to 762 cases in the period from 2014 to 2018 (12.5; 0–295). A total of 47 physicians responded to part 2 of the survey. Important indications for Re-RT that were considered were age, performance status, life expectancy, absence of distant metastases and time interval since previous radiotherapy. In addition to clinical decision-making factors, previous total radiation dose, volume of irradiated tissue and the biologically equivalent dose were considered during Re-RT planning. From the eight site-specific scenarios presented to the respondents, >60% of radiation oncologists agreed to perform Re-RT. Re-RT cases have increased in number, and interest in Re-RT among radiation oncologists has increased recently due to advances in technology. However, several problems exist that emphasize the need for consensus building and the establishment of guidelines for practice and prospective evaluation.  相似文献   
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The evolutionally conserved Cdc7 kinase plays crucial roles in initiation of DNA replication as well as in other chromosomal events. To examine the roles of Cdc7 in brain development, we have generated mice carrying Cdc7 knockout in neural stem cells by using Nestin-Cre. The Cdc7Fl/Fl NestinCre mice were born, but exhibited severe growth retardation and impaired postnatal brain development. These mice exhibited motor dysfunction within 9 days after birth and did not survive for more than 19 days. The cerebral cortical layer formation was impaired, although the cortical cell numbers were not altered in the mutant. In the cerebellum undergoing hypoplasia, granule cells (CGC) decreased in number in Cdc7Fl/F lNestinCre mice compared to the control at E15-18, suggesting that Cdc7 is required for DNA replication and cell proliferation of CGC at mid embryonic stage (before embryonic day 15). On the other hand, the Purkinje cell numbers were not altered but its layer formation was impaired in the mutant. These results indicate differential roles of Cdc7 in DNA replication/cell proliferation in brain. Furthermore, the defects of layer formation suggest a possibility that Cdc7 may play an additional role in cell migration during neural development.  相似文献   
95.
Background. Polymorphonuclear neutrophil elastase might contribute to postperfusion lung injury, so we evaluated the protective effect of ONO-5046·Na, a specific inhibitor of polymorphonuclear neutrophil elastase, against such an injury.

Methods. The study was done using 8 mongrel dogs that received ONO-5046·Na (15 mg/kg per hour) (group O) and 8 control dogs (group C), all of which had 1 hour of partial bypass and 5 hours of observation.

Results. The respiratory index showed no significant changes in group O, but increased significant in group C (1.4 ± 2.0 versus 5.1 ± 4.7, p = 0.0047). Pulmonary extravascular water volume increased markedly in group C but only slightly in group O (group C 20.6 ± 8.7, group O 11.2 ± 2.7 mL/kg; p = 0.0005). Blood concentrations of polymorphonuclear neutrophil elastase and interleukin-6 showed more than a tenfold increase in group C (PMN elastase, group C 12.9 ± 12.8, group O 2.4 ± 1.3 ng/mL; IL-b, group C 11.0 ± 9.3, group O 2.9 ± 3.8 pg/mL; p < 0.05) but were only slightly higher in group O. Histologic examination revealed interstitial and intraalveolar edema in group C, but group O was virtually normal.

Conclusions. ONO-5046·Na inhibits polymorphonuclear neutrophil elastase and maintains better pulmonary function, so it should reduce postperfusion lung injury.  相似文献   

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Suramin, a highly sulfonated drug, has been reported to be effective against several human malignancies in vitro and in vivo, and currently is undergoing clinical trials against prostate tumors. The biochemical and molecular mechanisms for suramin's antiproliferative activity are not clear. In order to define the biochemical basis for its antitumor activity and to enhance suramin's chemotherapeutic potential while decreasing its toxicity, we have examined interactions of suramin with topoisomerase I and 11 and several clinically active anticancer drugs against the human prostate (PC3 and LNCaP) cancer cell line. While etoposide, m-AMSA, camptothecin, and SN-38 (the active metabolite of CPT-11) were active in killing prostate cells as single agents, combinations of suramin and these agents were antagonistic against these cells. We found that suramin inhibited activities of purified topoisomerase I and II in vitro as measured by relaxation and cleavage assays. Further studies indicated that suramin also inhibited the drug-induced DNA damage in vitro and in isolated nuclei. These findings indicate that combinations of suramin with topoisomerase inhibitors, for example, VP-16, m-AMSA, or CPT, may not be beneficial to patients receiving suramin-containing chemotherapy. © 1993 Wiley-Liss, Inc.
  • 1 This article is a US Government work and, as such, is in the public domain in the United States of America
  • .  相似文献   
    98.
    The valvo-pump, an axial nonpulsatile blood pump implanted at the heart valve position, has been developed. The valvo-pump consists of an impeller and a motor, which are encased in a housing. An impeller with 5 vanes (22.0 mm in diameter) is used. The impeller is connected to a samarium-cobalt-rare earth magnet direct current (DC) brushless motor measuring 21.3 mm in diameter and 18.5 mm in length. Sealing is achieved by means of a ferrofluidic seal. A pump flow of 10.5 L/min was obtained at a pump differential pressure of 3.3 kPa (25 mm Hg), and a flow of 4.9 L/min was obtained at 7.0 kPa (53 mm Hg). Sealing was kept perfect against a pressure of 29.3 kPa (220 mm Hg) at 9,000 rpm.  相似文献   
    99.
    Continuous hyperthermic peritoneal perfusion (CHPP) with anticancer agents (mitomycin C and cisplatin) in warm saline was performed in patients with peritoneal dissemination of gastric cancer following resection of the primary lesion. The effect of CHPP was examined by a second-look operation. This study includes 41 cases of gastric cancer with peritoneal dissemination but without liver metastasis treated during the past 6 years. The overall median survival was 14.6 months to 64.2 months from CHPP to death and the 3-year survival rate was 28.5%. Second look surgery revealed a remarkable diminution in the degree of peritoneal dissemination in 7 (50%) of 14 patients with disappearance of ascites after only one course of CHPP in 7 (77.8%) of 9 patients. Long-term 3 year-survival was noted in 4 (9.8%) patients on CHPP. Side effects were renal insufficiency in 2 (5%) patients, leukopenia in 2 (5%) patients, and perforation of the small intestine in 1 (2%) patient. These results suggest the effectiveness of CHPP in the treatment of gastric cancer with peritoneal dissemination.
    Resumen La perfusión hipertérmica continua (PHTC) con agentes anticancerosos (mitocina G y cisplatino) y solutión salina fue realizada en pacientes con cáncer gástrico con diseminación peritoneal después de resección de la lesión primaria, y el efecto de PHTC fue determinado mediante reexploración (operación de second look, OSL). La población de pacientes está constituída por 41 casos de cáncer gástrico con diseminación peritoneal pero sin metástasis hepáticas, tratdos en el curso de los últimos 6 años. La sobrevida media global fue de 437 dias (rango 28 a 1925 días) desde la PHTC hasta la muerte y la tasa de sobrevida a 3 años fue 28.5%. La OSL reveló una notoria disminución de la diseminación peritoneal en 7 (50%) de 14 casos y desaparición de la ascites después de sólo un ciclo de PHTC en 7 de 9 casos con ascitis. Sobrevida de 3 años ocurrió en 4 casos. Los efectos colaterales fueron insuficiencia renal en 2 casos (5%), leucopenia en 2 casos (5%) y perforación del intestino delgado en 1 caso (2%). Los anteriores resultados sugieren que la PHTC es eficaz en el tratamiento del cáncer gástrico con diseminación peritoneal.

    Résumé La perfusion péritonéale continue hyperthermique (PPCH) avec des agents anticancéreux comme le mitomycine C et la cis-platine avec sérum physiologique chauffé a été instaurée lorsqu'une carcinose d'origine gastrique a été trouvée. Les effets de la PCH ont été évalués chez 16 patients lors d'un second-look (SL). Cette étude concerne 41 patients avec carcinose péritonéale sans métastase hépatique observés au cours des 6 dernières années. La survie globale médiane était de 437 jours (extrêmes 28 à 1925 jours): le taux de survie a 3 ans était de 28.5%. Les lésions avaient diminué de façon notable chez 7 (50%) de 14 patients. L'ascite a disparu dans 7 des 9 cas. Une survie à long terme (3 ans) a été notée dans 4 cas. Les effets secondaires ont été une insuffisance rénale dans 2 cas (5%), une leucopénie dans 2 cas (5%) et une perforation de l'intestin grêle dans un cas (2%). Les résultats suggèrent que la PPCH est efficace dans le traitement du cancer gastrique avec dissémination péritonéale.
      相似文献   
    100.
    We investigated by immunohistochemistry the deposition of alpha-synuclein in the brains of deceased patients with the parkinsonism-dementia complex (PDC) of Guam. Five of 13 PDC brains showed numerous alpha-synuclein positive neuronal inclusions and abnormal neurites, chiefly in the amygdala. Similar alpha-synuclein positive lesions were observed, although to a lesser extent, in the entorhinal cortex and the dorsal vagal nucleus. No alpha-synuclein positive inclusions were observed in motor cortex or locus coeruleus, and only a small number of positive inclusions were found in the Sommer's sector, temporal cortex, or substantia nigra. Some of the alpha-synuclein positive inclusions were reminiscent of cortical Lewy bodies (LB), but many of those in the amygdala coexisted with tau-positive pretangles and/or neurofibrillary tangles (NFT) within the same neurons. In these neurons, tau-positive shells encapsulated alpha-synuclein positive central cores or irregularly shaped alpha-synuclein-positive deposition intermingled with pretangles/NFT. Thus, the present study suggests that a common mechanism may govern aggregation of alpha-synuclein and tau in the amygdala, and that aggregation of alpha-synuclein may play some role in the neurodegenerative process of a tauopathy (i.e. PDC) in which Abeta deposition is virtually absent.  相似文献   
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