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21.
Butyrate infusions in the ovine fetus delay the biologic clock for globin gene switching. 总被引:4,自引:0,他引:4 下载免费PDF全文
S P Perrine A Rudolph D V Faller C Roman R A Cohen S J Chen Y W Kan 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(22):8540-8542
The switch from fetal to adult hemoglobin expression is regulated in many mammalian species by a developmental clock-like mechanism and determined by the gestational age of the fetus. Prolonging fetal globin gene expression is of considerable interest for therapeutic potential in diseases caused by abnormal beta-globin genes. Butyric acid, which is found in increased plasma concentrations in infants of diabetic mothers who have delayed globin gene switching, was infused into catheterized fetal lambs in utero during the time of the normal globin gene switch period. The globin gene switch was significantly delayed in three of four butyrate-treated fetuses compared with controls and was entirely prevented in one fetus in whom the infusion was begun before the globin switch was under way. These data provide a model for investigating and arresting the biologic clock of hemoglobin switching. 相似文献
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BALB/c mice were bilaterally implanted with bipolar electrodes either in anterodorsal (ADH) or posteroventral hippocampus (PVH) in order to compare the effects of postsession electrical stimulation on memory processes. For each experiment, 30 s after the end of the first session, the animals were stimulated during 80 s. For both hippocampal regions, the stimulation intensity was half of the afterdischarge threshold value. Control groups were naive, ADH and PVH implanted non-stimulated animals. Different appetitive and aversive tasks were used. Subseizure stimulation never created a deficit. Depending on the region of the hippocampus stimulated and on the learning task, a retention enhancement was eventually observed. These data are in agreement with the involvement of hippocampus in initial stages of memory consolidation. Further, the subseizure stimulation permitted a functional dissociation between the two hippocampal regions. Both regions seemed involved in the integration of information, but the anterodorsal part would be rather related to behavioral inhibition, while the posteroventral part would have the capacity to induce an arousal state allowing behavioral flexibility. 相似文献
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J S Sawyer R F Baldwin L E Rinkema C R Roman J H Fleisch 《Journal of medicinal chemistry》1992,35(7):1200-1209
This report describes the development of a series of highly potent quinoline-based leukotriene D4 (LTD4) receptor antagonists containing an N-benzyl-substituted phenyltetrazole moiety. They were designed to provide both the correct positioning of the acidic function and secondary lipophilic domain required for strong receptor binding. Members of this series possess high activity in blocking LTD4-induced contractions of isolated guinea pig ileum. Compound 32, LY287192 (2-[[5-[3-[2-(7-chloroquinolin-2- yl)ethenyl]phenyl]-2H-tetrazol-2-yl]methyl]-5-fluorobenzoic acid sodium salt), blocked contraction with a pKB value of 9.1 +/- 0.3. Qualitative structure-activity studies have demonstrated specific requirements for the best activity. In particular, ortho substitution of the benzyl group with an acidic function was crucial for maximum potency. In cases similar to 32, where the benzyl group possesses an ortho carboxylate, the N-2-substituted tetrazole isomer showed 100-fold greater activity relative to the corresponding N-1 isomer. This pattern was reversed when the acid was substituted at the para position. The quinoline unit may be replaced by other nitrogen-containing heterocycles. 相似文献
24.
J E Azevedo M A Fernandez D San Roman E Torrecilla R Esturau J Hernandez T Echeverria A Burgueno J L Delcan 《Revista portuguesa de cardiologia》1992,11(6):531-537
AIM OF STUDY: Evaluation by transesophageal echocardiography of the effect on the characteristics of physiological regurgitant jets (JF) resulting from prosthetic disfunction due to pathologic regurgitation (JF). PATIENTS AND METHODS: We studied 69 consecutive patients with the diagnosis of prosthesis in mitral position using transesophageal echocardiography and color doppler codification. The patients were divided in two groups (N and D groups) according to the presence of prosthesis disfunction by pathologic regurgitation. In each patient we determined planimetric areas and atrial peak depth of each JF and also the sum of JF planimetric areas of each mitral prosthesis. When pathological regurgitation was present we calculated the highest planimetric area, severity degree and atrial peak depth in each JP. RESULTS: The planimetric area in each JF of group N was 330 +/- 167 mm2 and in group D 117 +/- 116 mm2 (p less than 0.001). The sum of the areas of JF in group N was 474 +/- 204 mm2 and in group D 254 +/- 176 mm2 (p less than 0.01). The atrial depth of JF in group was 32 +/- 15 mm and in group D 26 +/- 18 mm (p less than 0.01). In group D 29% of the patients had mild pathological regurgitation, 10% moderate and 61% severe. The maximum planimetric area of JP in group D was 1078 +/- 1007 mm2 with atrial depth of 37 +/- 28 mm. CONCLUSION: The pathological regurgitation in disfunction prosthesis in mitral position has a significant reduction effect in the dimension of prosthesis physiologic regurgitation jets. This transesophageal echocardiographic observation makes it possible to characterize and clarify more precisely the different types of mitral prosthesis jets. 相似文献
25.
Mitchel A Kling Salvatore Alesci Gyorgy Csako Rene Costello David A Luckenbaugh Omer Bonne Roman Duncko Wayne C Drevets Husseini K Manji Dennis S Charney Philip W Gold Alexander Neumeister 《Neuropsychopharmacology》2007,62(4):309-313
BACKGROUND: Major depressive disorder (MDD) shows increased coronary artery disease (CAD) risk of unknown mechanism(s). MDD is more common in women than men; CAD diagnosis can be difficult in women. Elevations of the inflammatory markers C-reactive protein (CRP) and serum amyloid A (SAA) predict increased CAD risk in populations; few data on these markers exist in MDD, particularly in remitted patients. METHODS: We measured fasting am serum CRP (high sensitivity, CRP(hs)) and SAA in 18 unmedicated, remitted women with MDD (mean age 41 +/- (SD)12, body mass index (BMI) 25.2 +/- 4.1 kg/m(2)) and 18 BMI-matched healthy control subjects (age 36 +/- 10, BMI 25.3 +/- 3.8 kg/m(2)) on 2 separate occasions, > or = 6 days apart. RESULTS: Repeat SAA and CRP(hs) measurements strongly correlated across study days (SAA: r = .83, p < .001; CRP(hs): r = .94, p < .001). Both SAA (5.30 +/- 3.39 vs. 2.84 +/- 1.87 mg/L, p < .005) and CRP(hs) (3.23 +/- 3.17 vs. 1.12 +/- 1.45 mg/L; p < .01) were significantly elevated in MDD women versus controls. CONCLUSIONS: Elevated SAA and CRP(hs) in remitted, unmedicated women with MDD indicate a pro-inflammatory state unrelated to current depressive symptoms or pharmacotherapy. These findings suggest that inflammatory mechanisms may in part underlie findings of increased CAD risk in MDD. 相似文献
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Jacek Semenowicz Bogdan Koczy Przemys?aw Czuma Bart?omiej Pijet Tomasz Olszewski Roman Walo 《Chirurgia narzadów ruchu i ortopedia polska》2007,72(1):33-36
The Avantage double mobility press-fit cup was devised by Dr. Bousquet in the 70's to bring reasonable response to a problem of recurrent dislocation after total hip arthroplasty. The cup is attached to the femoral head by a bipolar polyethylene liner. The polyethylene liner moves freely inside a shiny--polished metal cup. The angular range of motion before impingement is increased by the mobility of the liner. The double connection (cup-liner, liner-head) reduces the stress on the metal cup and improve the stability of the prosthesis. The solution has proved to be efficient in reducing dislocation risk and maintains at the same time the appropriate range of motion. Between January 2004 and November 2005, 113 hip arthroplasties in 108 women with use of the double mobility cup were performed. The cemented version of the Avantage cup was inserted in 15 patients (mean age--76.9 years). Uncemented, HA coated implant was used in 98 patients (with mean age of 55 years). The mean follow-up was 20.4 months. No one patient was lost to follow-up. No postoperative dislocation was observed during follow-up. There was no unwanted leg lengthening greater than 1 cm. The Avantage cup may be indicated in any primary total hip arthroplasty especially in those with increased risk of postoperative dislocations. This cup enables a correct balance of the hip without a need of the unwanted lengthening of the leg. 相似文献
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