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51.
Antisense oligonucleotides are short pieces of synthetic, chemically modified DNA or RNA that are designed to interact by Watson-Crick base pairing with mRNA encoding a targeted protein. During the past 20 years the technology associated with the development of antisense has improved dramatically, and emerging chemistries have made antisense oligonucleotides into powerful and versatile tools to study the function of proteins in living cells. The dramatic increase in novel genomic sequence information that has recently become available has generated enormous opportunities for the development of antisense oligonucleotides capable of altering the expression level of virtually any gene. With this will come a nearly equal opportunity to determine the role of individual proteins in a vast array of cardiovascular disease. The great specificity that these compounds exhibit in vitro suggests that they may also have an exciting future for development into therapeutics useful for the treatment of human disease. This review highlights some of the advances made in the field of antisense research, placing an emphasis on uses and proper controls. 相似文献
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Honkanen JO Kostamo A Kukkonen JV 《Archives of environmental contamination and toxicology》2005,48(3):391-396
The study concerns the toxicity of a phytosterol mixture, ultrasitosterol, consisting mainly of -sitosterol 75.7% and -sitostanol 13.0%, to grayling (Thymallus thymallus) embryos. Eyed eggs were exposed to three concentrations (1 g/l, 10 g/l, and 50 g/l) of ultrasitosterol for 4 weeks. Embryos and later on hatched fry were taken for triiodothyronine (T3), thyroxine (T4), and histopathological analyses after 7, 14, 21, and 28 days of exposure. Most of the eggs (>95%) hatched during the first week of exposure, and ultrasitosterol treatment shortened hatching time significantly (p 0.0001) at all exposure concentrations in comparison to the control. Ultrasitosterol did not have any significant effect on T3 or T4 levels in the embryo extracts. However, an interesting observation was that T3 levels increased in all treatments and in the control near the time of hatching. In conclusion, ultrasitosterol showed potential to affect the development of grayling embryos and fry, but further long-term exposure experiments are needed to verify these changes in more detail. 相似文献
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Honkanen T Mustonen J Kainulainen H Myllymäki J Collin P Hurme M Rantala I 《Kidney international》2005,67(6):2187-2195
BACKGROUND: Clinical manifestation of IgA nephropathy (IgAN) strikingly occurs after respiratory tract infections. An intestinal inflammation has also been described. We hypothesized that the intestinal inflammation should manifest itself as an increase in inflammatory cells and mucosal cyclooxygenase 2 (COX-2) expression. METHODS: By using immunohistochemistry, we determined the phenotype and quantity of inflammatory cells in duodenal biopsy specimens from 17 IgAN patients. Control material comprised 18 patients undergoing gastroscopy because of dyspepsia. RESULTS: All the biopsy specimens disclosed normal villous architecture. In IgAN, CD3(+) cells and COX-2-positive cells were significantly increased and J chain-producing plasma cells were significantly decreased. CD3(+) cells coexpressed COX-2 protein and COX-2-positive cells also expressed CD45RO antigen. The number of lymphocytes correlated significantly with serum IgA and COX-2-expression with serum IgA and the degree of hematuria. COX-2-positive subepithelial fibroblasts were a conspicuous finding in IgAN. In CD68(+) and CD15(+) cells, a significant increase was seen. Many of these cells also expressed COX-2 protein. CD15(+) positivity correlated significantly with proteinuria in IgAN. CONCLUSION: Our results indicate that small bowel inflammation in IgAN shows itself as an increased number of mucosal inflammatory cells. However, polymeric IgA production is significantly decreased. An increased mucosal COX-2 expression suggests activation of the inflammatory cells and the degree of inflammation significantly correlates with serum IgA and the amount of proteinuria and hematuria. Subepithelial fibroblasts seem also to be involved in the inflammatory reaction. 相似文献
56.
WHO multinational study of three misoprostol regimens after mifepristone for early medical abortion 总被引:5,自引:0,他引:5
Honkanen H Piaggio G Hertzen H Bártfai G Erdenetungalag R Gemzell-Danielsson K Gopalan S Horga M Jerve F Mittal S Thi Nhu Ngoc N Peregoudov A Prasad RN Pretnar-Darovec A Shah RS Song S Tang OS Wu SC;WHO Research Group on Post-Ovulatory Methods for Fertility Regulation 《BJOG : an international journal of obstetrics and gynaecology》2004,111(7):715-725
57.
Measurement of the abdominal circumference for the detection of intra-abdominal hemorrhage has no diagnostic value 总被引:1,自引:0,他引:1
Castrén M Liukko K Nurmi J Honkanen E Lindgren L 《Acta anaesthesiologica Scandinavica》2004,48(5):592-594
BACKGROUND: Measuring the circumference of the abdomen is still commonly used when treating a patient with suspicion of intra-abdominal bleeding. In the present study the usefulness of this method for a diagnostic purpose is questioned because of the assumed method-related interindividual variation. METHODS: The study group consisted of 34 end-stage renal failure (ERSF) patients treated with peritoneal dialysis. Each patient was measured by the same nurse at the level of the umbilicus and the level of the iliac crest both before and after an infusion of 2000 ml of peritoneal dialysis fluid into the peritoneal cavity. One healthy female served as a control. Her abdominal circumference was measured at the level of the umbilicus by 10 different emergency medical technicians (EMTs), each of whom performed the measurement three times. The measuring tape was blank and the place of the first measurement was marked as performed in clinical practice. RESULTS: The mean abdominal circumference at the level of the umbilicus before an infusion of peritoneal fluid was 93.2 +/- 9.5 cm (SD), and after filling the peritoneal cavity 96.3 +/- 9.5 cm (difference 3.1 +/- 1.7 cm). These figures at the level of the iliac crest were 96 +/- 8.3 and 97.2 +/- 8.4 cm (difference 1.2 +/- 1.4 cm) (P < 0.0001), respectively. The mean value between the smallest and largest values when measuring the circumference of a healthy control person was 1.85 +/- 1.11 (P < 0.0005). The mean difference in circumference in the peritoneal dialysis patients was smaller than the largest difference among the three measurements taken by the same EMT. CONCLUSION: Measuring the abdominal circumference should not be used as a diagnostic tool when intra-abdominal bleeding is suspected. 相似文献
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OBJECTIVES: Coating an implant with albumin prevents adhesion of proteins, bacteria, and platelets and thus may lead to its improved and prolonged function. Previously, we have demonstrated the inhibition of binding of fibronectin, one of the most adhesive glycoproteins, on human serum albumin (HSA)-coated tympanostomy tubes and the durability of this binding inhibition in a 8-month trial. We have also demonstrated that the HSA coating inhibits the binding of Staphylococcus aureus and Pseudomonas aeruginosa to titanium plates. This prospective study evaluated the effect of albumin coating on tympanostomy tube sequelae and on the outcome of tympanostomized patients. STUDY DESIGN: Double-blind, prospective, randomized clinical trial. METHODS: Two otolaryngological centers in southern Finland enrolled 179 pediatric patients. Number of tube occlusions and otorrhea and tube ventilation time in the ears with HSA-coated titanium tympanostomy tubes were compared with the contralateral ear with its uncoated, otherwise identical titanium tube during a 9-month follow-up period. RESULTS: In HSA-coated tubes, average ventilation time was slightly longer and the number of early tube occlusions significantly less (P < .05). Moreover, in patients with perioperative bleeding, the coating prolonged average ventilation time of tympanostomy tubes significantly (P < .05). CONCLUSIONS: HSA coating reduces early tube occlusions by preventing adherence of blood and secretion. 相似文献
59.
Koivumaa-Honkanen H Kaprio J Honkanen R Viinamäki H Koskenvuo M 《Social psychiatry and psychiatric epidemiology》2004,39(12):994-999
OBJECTIVE: The aim of this study was to investigate the cross-sectional and longitudinal relationship between life satisfaction and depressive symptoms in healthy adults. METHOD: This is a 15-year prospective cohort study with a nationwide sample of healthy Finnish adults (N = 9679), aged 18-45, who responded to postal questionnaires in 1975, 1981 and 1990 including a 4-item life satisfaction (LS) scale (range 4-20) and, in 1990, the 21-item Beck Depression Inventory (BDI). RESULTS: A strong linear association was found between concurrent LS and BDI scales (r = 0.6). With an LS cut-off point of 11/12, moderate/severe depression (BDI > or = 19) was detected with 87% sensitivity, 88 % specificity and a 94% area under the ROC curve. Longitudinally, a strongly increased risk of moderate/severe depression in 1990 was observed among the dissatisfied (LS 12-20) compared with the satisfied (LS 4-6) in 1975 (OR = 6.7; 95 %CI 4.2-10.9) and in 1981 (OR = 10.4; 6.1-17.6). CONCLUSION: The 4-item LS scale can identify a group of healthy people from the general population with a high risk of having or developing depressive symptoms. Since low life satisfaction also indicates an elevated risk of other adverse health outcomes, the assessment of subjective well-being should be encouraged both in surveys and in clinical practice. 相似文献
60.
Koivisto M Virjonen T Heikkilä T Lehto VP 《Journal of pharmaceutical and biomedical analysis》2004,36(3):559-564
The crystallographic texture, i.e. the preferred orientation of crystallites of delta-mannitol samples, has been experimentally determined by pole figure analysis. The pole figures were measured with an X-ray diffraction texture goniometer. It was found that already the uncompressed delta-mannitol powder sample was slightly texturized so that the (0 2 0) plane was parallel to the upper surface of the sample. The degree of preferred orientation was found to significantly increase when the powder was compressed to a tablet with the minimum (74MPa) compression pressure. Nevertheless, the direction of the texture remained parallel to the tablet surface. Maximum compression (740MPa) did not increase the degree of preferred orientation further. The compression time (0 or 60s) was not found to noticeably affect the strength or direction of the texture. The extent of the texture inside the tablet was determined with a tablet surface grinding experiment. The degree of preferred orientation was found to decrease under the surface while the orientation remained the same. The results were confirmed with orientation distribution function (ODF) calculations. 相似文献