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991.
Heikkilä P Teronen O Moilanen M Konttinen YT Hanemaaijer R Laitinen M Maisi P van der Pluijm G Bartlett JD Salo T Sorsa T 《Anti-cancer drugs》2002,13(3):245-254
Bisphosphonates (clodronate, alendronate, pamidronate and zoledronate) at therapeutically attainable non-cytotoxic concentrations inhibited MMP-3, -12, -13 and -20 as well as MMP-1, -2, -8 and -9, but not urokinase-type plasminogen activator (uPA), a serine proteinase and a pro-MMP activator. Dose-dependent inhibition was shown by three independent MMP assays. The inhibition was reduced in the presence of an increased concentration of Ca(2+) when compared to physiologic Ca(2+) concentration. Alendronate inhibited the in vitro invasion (Matrigel) of human HT1080 fibrosarcoma and C8161 melanoma cells, and the random migration of these malignant and endothelial cell lines capable of expressing MMPs and uPA. The concentration of alendronate required to inhibit 50% of the activity (IC(50)=40-70 microM) of MMPs corresponded to the IC(50) of down-regulation of in vitro invasion and migration. The ability of bisphosphonates to down-regulate the in vitro invasion and random migration was comparable or slightly better in relation to the selective gelatinase inhibitor CTTHWGFTLC peptide. Alendronate but not CTTHWGFTLC peptide promoted the adhesion of HT1080 fibrosarcoma and C8161 melanoma cell lines on fibronectin. Bisphosphonates are broad-spectrum MMP inhibitors and this inhibition involves cation chelation. Bisphosphonates further exert antimetastatic, anti-invasive and cell adhesion-promoting properties, which may prevent metastases not only into hard tissues but also to soft tissues. 相似文献
992.
In vivo effects of bisphenol A on the polecat (mustela putorius) 总被引:1,自引:0,他引:1
Nieminen P Lindström-Seppä P Juntunen M Asikainen J Mustonen AM Karonen SL Mussalo-Rauhamaa H Kukkonen JV 《Journal of toxicology and environmental health. Part A》2002,65(13):933-945
Bisphenol A (BPA), an environmental estrogen derived from the plastic industry, was given orally via incorporation into the food of 30 male and female polecats at 3 different doses (10, 50, or 250 mg/kg body weight/day) for 2 wk with 10 animals acting as controls. Several hormone levels in the plasma were determined as well as the activities of the phase I and II biotransformation enzymes 7-ethoxyresorufin O-deethylase (EROD), cytosolic glutathione S-transferase (GST), and UDP-glucuronosyltransferase (UDPGT). BPA did not cause any macroscopic effects on body mass or the health of the animals. UDPGT and GST activities increased significantly in direct correlation with increasing BPA exposure in females and UDPGT increased in a dose-related manner in males. There was no change in the plasma T4 and testosterone concentrations of the males with increasing BPA exposure. Discriminant analysis indicated that the group receiving 10 mg BPA/kg body weight/d was not different from the control group but the groups receiving 50 and 250 mg/kg body weight/d were different from the control group. This suggests physiological changes in the groups receiving 50 or 250 mg BPA/kg body weight/d. 相似文献
993.
Cannon TD Huttunen MO Dahlström M Larmo I Räsänen P Juriloo A 《The American journal of psychiatry》2002,159(7):1230-1232
OBJECTIVE: The safety and tolerability of short-term treatment with a low dose of risperidone was evaluated in adolescents with prodromal symptoms and a family history of schizophrenia. METHOD: Four prodromal high-risk adolescents and six first-episode patients with schizophrenia were treated with average doses of 1.0 and 1.8 mg/day of risperidone, respectively, in an 8- to 12-week open-label trial. RESULTS: No significant treatment-related adverse events were noted. Severity of thought and behavior disturbance ratings declined by about 30%; performance on a test of verbal learning improved by about 100% during treatment in both prodromal and first-episode patients, changes that achieved statistical significance despite the small group sizes. CONCLUSIONS: These findings are preliminary and should not be used to guide health care decisions at this time. Randomized controlled trials are needed to determine whether antipsychotic drug treatment of prodromal patients can delay or prevent onset or attenuate the clinical course of schizophrenia. 相似文献
994.
Stern AM 《American journal of public health》2002,92(5):742-752
In 1920, Indiana's Division of Infant and Child Hygiene inaugurated its first Better Babies Contest at the state fair. For the next 12 years, these contests were the centerpiece of a dynamic infant and maternal welfare program that took shape in Indiana during the decade of the federal Sheppard-Towner act. More than just a lively spectacle for fairgoers, these contests brought public health, "race betterment," and animal breeding together in a unique manner. This article describes one of the most popular expressions of public health and race betterment in rural America. It also raises questions about the intersections between hereditarian and medical conceptions of human improvement during the early 20th century, especially with respect to child breeding and rearing. 相似文献
995.
996.
Late traumatic dislocation of laser in situ keratomileusis flaps 总被引:1,自引:0,他引:1
Heickell AG Vesaluoma MH Tervo TM Vannas A Krootila K 《Journal of cataract and refractive surgery》2004,30(1):253-256
We present 2 patients with late traumatic laser in situ keratomileusis flap dislocation 8 months and 17 months after surgery. One patient had a sharp trauma that caused a partial laceration and the second patient had a blunt trauma that caused a dislocation of the flap. The corneas were examined with slitlamp microscopy, computed corneal topography, and confocal microscopy. One flap was repositioned surgically; the other was treated conservatively with an eye patch. The final visual outcomes were good and illustrate the benefit of immediate attention and flap repositioning. 相似文献
997.
Identification of the E1A-regulated transcription factor p120 E4F as an interacting partner of the RASSF1A candidate tumor suppressor gene 总被引:6,自引:0,他引:6
998.
Immortalization of human bronchial epithelial cells in the absence of viral oncoproteins 总被引:7,自引:0,他引:7
999.
Sathyanarayana UG Maruyama R Padar A Suzuki M Bondaruk J Sagalowsky A Minna JD Frenkel EP Grossman HB Czerniak B Gazdar AF 《Cancer research》2004,64(4):1425-1430
Laminin-5 (LN5) anchors epithelial cells to the underlying basement membrane, and it is encoded by three distinct genes: LAMA3, LAMB3, and LAMC2. To metastasize and grow, cancer cells must invade and destroy the basement membrane. Our previous work has shown that epigenetic inactivation is a major mechanism of silencing LN5 genes in lung cancers. We extended our methylation studies to resected bladder tumors (n = 128) and exfoliated cell samples (bladder washes and voided urine; n = 71) and correlated the data with clinicopathologic findings. Nonmalignant urothelium had uniform expression of LN5 genes and lacked methylation. The methylation frequencies for LN5 genes in tumors were 21-45%, and there was excellent concordance between methylation in tumors and corresponding exfoliated cells. Methylation of LAMA3 and LAMB3 and the methylation index were correlated significantly with several parameters of poor prognosis (tumor grade, growth pattern, muscle invasion, tumor stage, and ploidy pattern), whereas methylation of LAMC2 and methylation index were associated with shortened patient survival. Of particular interest, methylation frequencies of LAMA3 helped to distinguish invasive (72%) from noninvasive (12%) tumors. These results suggest that methylation of LN5 genes has potential clinical applications in bladder cancers. 相似文献
1000.