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41.
Identification of differentially expressed genes in aflatoxin B1- treated cultured primary rat hepatocytes and Fischer 344 rats 总被引:4,自引:1,他引:4
Harris AJ; Shaddock JG; Manjanatha MG; Lisenbey JA; Casciano DA 《Carcinogenesis》1998,19(8):1451-1458
Aflatoxin B1 (AFB1), a mutagen and hepatocarcinogen in rats and humans, is
a contaminant of the human food supply, particularly in parts of Africa and
Asia. AFB1-induced changes in gene expression may play a part in the
development of the toxic, immunosuppressive and carcinogenic properties of
this fungal metabolite. An understanding of the-role of AFB1 in modulating
gene regulation should provide insight regarding mechanisms of AFB1-induced
carcinogenesis. We used three PCR- based subtractive techniques to identify
AFB1-responsive genes in cultured primary rat hepatocyte RNA: differential
display PCR (DD-PCR), representational difference analysis (RDA) and
suppression subtractive hybridization (SSH). Each of the three techniques
identified AFB1- responsive genes, although no individual cDNA was isolated
by more than one technique. Nine cDNAs isolated using DD-PCR, RDA or SSH
were found to represent eight genes that are differentially expressed as a
result of AFB1 exposure. Genes whose mRNA levels were increased in cultured
primary rat hepatocytes after AFB1 treatment were corticosteroid binding
globulin (CBG), cytochrome P450 4F1 (CYP4F1), alpha-2 microglobulin,
C4b-binding protein (C4BP), serum amyloid A-2 and glutathione S-transferase
Yb2 (GST). Transferrin and a small CYP3A-like cDNA had reduced mRNA levels
after AFB1 exposure. Full-length CYP3A mRNA levels were increased. When
liver RNA from AFB1-treated male F344 rats was evaluated for transferrin,
CBG, GST, CYP3A and CYP4F1 expression, a decrease in transferrin mRNA and
an increase in CBG, GST, CYP3A and CYP4F1 mRNA levels was also seen.
Analysis of the potential function of these genes in maintaining cellular
homeostasis suggests that their differential expression could contribute to
the toxicity associated with AFB1 exposure.
相似文献
42.
Jordan JA Gallagher AG McGuigan J McGlade K McClure N 《American journal of surgery》2000,180(3):208-211
OBJECTIVES: To evaluate virtual reality as a laparoscopic training device in helping surgeons to automate to the "fulcrum effect" by comparing it to time-matched training programs using randomly alternating images (ie, y-axis inverted and normal laparoscopic) and normal laparoscopic viewing conditions. METHODS: Twenty-four participants (16 females and 8 males), were randomly assigned to minimally invasive surgery virtual reality (MIST VR), randomly alternating (between y-axis inverted and normal laparoscopic images), and normal laparoscopic imaging condition. Participants were requested to perform a 2-minute laparoscopic cutting task before and after training. RESULTS: In the test trial participants who trained on the MIST VR performed significantly better than those in the normal laparoscopic and randomly alternating imaging conditions. CONCLUSION: The results show that virtual reality training may provide faster skill acquisition with particular reference to automation of the fulcrum effect. MIST VR provides a new way of training laparoscopic psychomotor surgical skills. 相似文献
43.
OBJECTIVE: Community based models for injury prevention have become an accepted part of the overall injury control strategy. This systematic review of the scientific literature examines the evidence for their effectiveness in reducing all-cause injury in children 0-14 years of age. METHODS: A comprehensive search of the literature was performed using the following study selection criteria: community based intervention study; children under 14 years; outcome measure was injury rates; and either a community control or an historical control was used in the design. Quality assessment and data abstraction were guided by a standardized procedure and performed independently by two authors. Data synthesis was in tabular and text form with meta-analysis not being possible due to the discrepancy in methods and measures between the studies. RESULTS: Thorough electronic and library search techniques yielded only nine formally evaluated community based all-cause child injury prevention programs that have reported actual injury outcomes. Of these nine studies, seven provided high level evidence where contemporary control communities were used for comparison; the remaining two used a pre and post-design or time trend analysis where historical data from the community were used as the comparison. Only three of the seven studies with contemporary control communities found significant effect of the intervention; the two studies without controls noted significant reductions in injury rates after the intervention period. CONCLUSION: There is a paucity of research from which evidence regarding the effectiveness of community based childhood injury prevention programs can be obtained and hence a clear need to increase the effort on developing this evidence base. 相似文献
44.
Danny Rischin Lester Peters Richard Fisher Andrew Macann Jim Denham Michael Poulsen Michael Jackson Lizbeth Kenny Michael Penniment June Corry David Lamb Bev McClure 《Journal of clinical oncology》2005,23(1):79-87
PURPOSE: To select one of two chemoradiotherapy regimens for locally advanced squamous cell carcinoma (SCC) of the head and neck as the experimental arm for the next Trans-Tasman Radiation Oncology Group phase III trial. PATIENTS AND METHODS: One hundred twenty-two previously untreated patients with stage III/IV SCC of the head and neck were randomized to receive definitive radiotherapy (70 Gy in 7 weeks) concurrently with either cisplatin (75 mg/m(2)) plus tirapazamine (290 mg/m(2)/d) on day 2 of weeks 1, 4, and 7, and tirapazamine alone (160 mg/m(2)/d) on days 1, 3, and 5 of weeks 2 and 3 (TPZ/CIS), or cisplatin (50 mg/m(2)) on day 1 and infusional fluorouracil (360 mg/m(2)/d) on days 1 through 5 of weeks 6 and 7 (chemoboost). RESULTS: Three-year failure-free survival rates were 55% with TPZ/CIS (95% CI, 39% to 70%) and 44% with chemoboost (95% CI, 30% to 60%; log-rank P = .16). Three-year locoregional failure-free rates were 84% in the TPZ/CIS arm (95% CI, 71% to 92%) and 66% in the chemoboost arm (95% CI, 51% to 79%; P = .069). More febrile neutropenia and grade 3 or 4 late mucous membrane toxicity were observed with TPZ/CIS, while acute skin radiation reaction was more severe and prolonged with chemoboost. Compliance with protocol treatment was satisfactory on both arms. CONCLUSION: Both regimens are feasible and are associated with significant but acceptable toxicity profiles in the cooperative group setting. Based on the promising efficacy seen in this trial, TPZ/CIS is being evaluated in a large phase III trial. 相似文献
45.
目的:探讨输尿管硬镜在尿路疾病治疗中的应用效果。方法:对1000例尿路结石、输尿管及尿道狭窄、输尿管息肉、梗阻、异物存留等患者,均以输尿管硬镜配合其他设备进行治疗。结果:肾内结石34例治愈率76.5%,输尿管结石、膀胱及尿道结石治愈率为94.5%~99.8%;泌尿道狭窄治愈率66.7%~75%;33例泌尿道异物取出率97%。结论:基层医院在尿路疾病治疗中,根据病变的不同部位,将输尿管硬镜灵活配合现有并不高档的设备,同样可以取得较好的微创手术效果。 相似文献
46.
Jerome L. Belinson M.D. R.G. Pretorius M.D. Maura McClure R.N. Takamaru Ashikaga Ph.D. 《Gynecologic oncology》1986,23(3):304-309
Thirty-three patients were treated with HexAF after previous treatment with cyclophosphamide (C), Adriamycin (A), and cisplatin (P). The patients had either progressed on CAP, had persistent disease after CAP, or recurred after a negative second look. Treatment schedule was hexamethylmelamine (Hex) 150 mg po qd days 1-14, methotrexate (A) 40 mg/m2 IV days 1 and 8, and 5-fluorouracil (F) 600 mg/m2 IV days 1 and 8. Courses were repeated every 4 weeks. Thirty-one of 33 patients were evaluable for response. Three of 31 patients had partial responses, 7 of 31 had stable disease, and 21 of 31 progressed. Median survival of the responders (n = 3) was 23 months and the nonresponders (n = 28) was 6 months (p = 0.027). Patients with less than 1 cm disease (n = 12) had a median survival of 20 months, and those with greater than 1 cm (n = 21) had a median survival of 6 months (p = 0.004). Toxicity was mild. Even with a statistically significant survival advantage for HexAF responders, we consider a response rate of less than 10% unacceptable. 相似文献
47.
A 34-year-old female presented with a right ovarian Krukenberg tumor, which initially was thought to be a granulosa cell tumor. Eight months later, necropsy revealed a primary signet-ring cell carcinoma (SRCC) of the urinary bladder. When occurring in females, this rare bladder tumor often exhibits ovarian metastases. This case appears to be the first reported example of a signet-ring cell carcinoma of the bladder presenting as a Krukenberg tumor. 相似文献
48.
49.
Two year follow-up of 80 surviving preterm babies from a controlled trial of surfactant replacement is reported. There were no statistically significant differences in rates of hospital admission, respiratory infections or antibiotic treatment. Wheezing, skin rashes and food intolerance were reported by parents with similar frequency in each group. Weight, length and occipito-frontal circumference were similar at all ages up to and including 2 years. Median developmental quotient (Griffiths scales) was 100 in the treated group and 95 in the control group (P = 0.053). Rates of cerebral palsy were similar in each group although milder forms predominated in the treated group. It is concluded that artificial surfactant (dipalmitoylphosphatidylcholine and high-density lipoprotein) replacement at birth is not associated with adverse long term effects on preterm babies. 相似文献
50.
In the 50 years since the first edition of this journal, operative paediatric surgery has undergone radical change. Many of the most common instruments are unchanged, both as a testament to their utility and in recognition of past surgeons remembered eponymously. Surrounding that basic core of instruments, theatre has changed radically as new tools and techniques have arisen. Surgeons have come down from their pedestals, recognising surgery as a team sport rather than a solo performance. More than half of the current paediatric surgical trainees are women, a higher proportion than in any other craft group of the Royal Australasian College of Surgeons. The appearance, and rapid development, of laparoscopy is to many observers the most notable change in surgery over the last 50 years. Placed in its context though, it is simply the most prominent example of a frameshift in surgical thinking. The patient as a whole is now the focus, rather than just the disease. Recent developments are as much about minimising harm to normal tissues as they are about extirpating pathology. As a surgical maxim, ‘Primum non nocere’ is even more in evidence in 2015 than it was in 1965. 相似文献