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991.
Bhatia JK Korelitz BI Panagopoulos G Lobel E Mirsky F Sultan K DiSanti W Chun A Keenan G Mamun K 《Journal of clinical gastroenterology》2007,41(7):677-681
PURPOSE: To evaluate treatment response to intravenous (IV) infliximab (IFX) as a first-line therapy in patients hospitalized for severe Crohn's disease and compare it with our earlier data using IV hydrocortisone. METHODS: Seventeen cases received IFX (5 mg/kg) and were matched for the same goal of therapy to those who had received hydrocortisone (300 mg/d). The Crohn's and Colitis Foundation of America-International Organization of Inflammatory Bowel Disease (CCFA-IOIBD) score was obtained for the IFX-treated cases on admission and daily and the Crohn's disease activity index (CDAI) score weekly throughout the hospitalization and compared with those who received hydrocortisone. Discharge was guided by the same criteria in both groups. RESULTS: For the IFX group, the admission mean CCFA-IOIBD score was 13.5 (+/-4.4). Eight of 17 patients achieved a clinical response with a mean score of 4 (+/-1.5), representing a >or=50% reduction from baseline to discharge. The mean admission score for the hydrocortisone group was 17.75 (+/-7.1) with 13 of 16 achieving a mean score of 4.5 (+/-2.3). The mean discharge score for the 17 IFX patients was 6.9 (+/-3) and for the hydrocortisone group was 5.9 (+/-3.2). Median length of hospitalization for the IFX patients was 4 days (range 1 to 9) and 7.5 (5 to 15) days for the hydrocortisone group (P<0.001). CONCLUSIONS: IFX therapy was an effective first-line agent in patients with severe Crohn's disease who require hospitalization and therefore a primary treatment option. Most patients receiving IFX can anticipate a briefer hospitalization than with IV hydrocortisone. Failure of an early response can provide an opportunity to consider an alternate form of therapy sooner with IFX than with hydrocortisone. 相似文献
992.
Bhatia V 《International journal of cardiology》2007,116(3):e80-e81
With the availability of better hardware and refinements in catheterization techniques, perforation of cardiac structures at cardiac catheterization is a rare event. We report, a 54-year old male who developed LV rupture during a pre-aortic valve replacement catheterization with ensuing tamponade, after several attempts were made to cross a heavily calcified aortic valve. The issues regarding whether the calcific aortic valve should be crossed when reliable echo and color Doppler information is available are discussed along with recent recommendations. 相似文献
993.
994.
Recombinant human butyrylcholinesterase from milk of transgenic animals to protect against organophosphate poisoning 总被引:10,自引:0,他引:10 下载免费PDF全文
Huang YJ Huang Y Baldassarre H Wang B Lazaris A Leduc M Bilodeau AS Bellemare A Côté M Herskovits P Touati M Turcotte C Valeanu L Lemée N Wilgus H Bégin I Bhatia B Rao K Neveu N Brochu E Pierson J Hockley DK Cerasoli DM Lenz DE Karatzas CN Langermann S 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(34):13603-13608
Dangerous organophosphorus (OP) compounds have been used as insecticides in agriculture and in chemical warfare. Because exposure to OP could create a danger for humans in the future, butyrylcholinesterase (BChE) has been developed for prophylaxis to these chemicals. Because it is impractical to obtain sufficient quantities of plasma BChE to treat humans exposed to OP agents, the production of recombinant BChE (rBChE) in milk of transgenic animals was investigated. Transgenic mice and goats were generated with human BChE cDNA under control of the goat beta-casein promoter. Milk from transgenic animals contained 0.1-5 g/liter of active rBChE. The plasma half-life of PEGylated, goat-derived, purified rBChE in guinea pigs was 7-fold longer than non-PEGylated dimers. The rBChE from transgenic mice was inhibited by nerve agents at a 1:1 molar ratio. Transgenic goats produced active rBChE in milk sufficient for prophylaxis of humans at risk for exposure to OP agents. 相似文献
995.
Newsome SD Etnier MA Gifford-Gonzalez D Phillips DL van Tuinen M Hadly EA Costa DP Kennett DJ Guilderson TP Koch PL 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(23):9709-9714
Historical data provide a baseline against which to judge the significance of recent ecological shifts and guide conservation strategies, especially for species decimated by pre-20th century harvesting. Northern fur seals (NFS; Callorhinus ursinus) are a common pinniped species in archaeological sites from southern California to the Aleutian Islands, yet today they breed almost exclusively on offshore islands at high latitudes. Harvest profiles from archaeological sites contain many unweaned pups, confirming the presence of temperate-latitude breeding colonies in California, the Pacific Northwest, and the eastern Aleutian Islands. Isotopic results suggest that prehistoric NFS fed offshore across their entire range, that California populations were distinct from populations to the north, and that populations breeding at temperate latitudes in the past used a different reproductive strategy than modern populations. The extinction of temperate-latitude breeding populations was asynchronous geographically. In southern California, the Pacific Northwest, and the eastern Aleutians, NFS remained abundant in the archaeological record up to the historical period approximately 200 years B.P.; thus their regional collapse is plausibly attributed to historical hunting or some other anthropogenic ecosystem disturbance. In contrast, NFS populations in central and northern California collapsed at approximately 800 years B.P., long before European contact. The relative roles of human hunting versus climatic factors in explaining this ecological shift are unclear, as more paleoclimate information is needed from the coastal zone. 相似文献
996.
Zwezdaryk KJ Coffelt SB Figueroa YG Liu J Phinney DG LaMarca HL Florez L Morris CB Hoyle GW Scandurro AB 《Experimental hematology》2007,35(4):640-652
OBJECTIVE: The ability of erythropoietin (EPO) to elicit a pro-angiogenic effect on human mesenchymal stem cells (hMSC) was tested. hMSC are currently under study as therapeutic delivery agents that target tumor vessels. Hypoxia favors the differentiation of hMSC towards a pro-angiogenic program. However, the classical angiogenic factors, vascular endothelial growth factor and basic fibroblast growth factor, are not fully capable of restoring this effect. The hypoxia-regulated factor, EPO, induces angiogenesis in endothelial cells. Here, EPO's pro-angiogenic effect on hMSC was analyzed. METHODS: hMSC were tested for EPO receptor expression by western blot, immunofluorescence, and flow cytometry assays. Downstream receptor signaling components JAK and STAT were measured by standard assays. Pro-angiogenesis effects mediated by EPO treatment of hMSC were measured by proliferation, cytokine, or pro-angiogenesis factor secretion, metalloprotease activation, migration, invasion, wound healing, and tubule formation assays. RESULTS: hMSC express the cognate EPO receptor and are capable of promoting angiogenesis following EPO treatment in all the angiogenesis assays tested. EPO-treated hMSC proliferate and secrete pro-angiogenesis factors more readily than untreated hMSC. EPO leads to increased hMSC chemotaxis, migration, and activation of matrix metalloprotease-2. This treatment causes greater recruitment of vessels as measured in an in vivo angiogenesis assay. CONCLUSION: EPO is capable of eliciting a pro-angiogenesis program in hMSC that instigates secretion of angiogenic factors and the subsequent recruitment of endothelium. This study defines a novel mechanism for tumor cell recruitment of blood vessels that is important to consider in the design of stem cell-based therapies. 相似文献
997.
998.
Robia SL Campbell KS Kelly EM Hou Z Winters DL Thomas DD 《Circulation research》2007,101(11):1123-1129
Phospholamban (PLB) or the sarcoplasmic reticulum Ca2+-ATPase (SERCA) were fused to cyan fluorescent protein (CFP) and coexpressed with PLB fused to yellow fluorescent protein (YFP). The expressed fluorescently tagged proteins were imaged using epifluorescence and total internal reflection fluorescence microscopy. YFP fluorescence was selectively bleached by a focused laser beam. CFP fluorescence at the targeted site increased after YFP photobleaching, indicating fluorescence resonance energy transfer between CFP-SERCA/CFP-PLB and YFP-PLB. The increased donor fluorescence relaxed back toward baseline as a result of donor diffusion and exchange of bleached YFP-PLB for unbleached YFP-PLB, which restored fluorescence resonance energy transfer. Requenching of CFP donors, termed F?rster transfer recovery (FTR), was quantified as an index of the rate of PLB subunit exchange from the PLB:SERCA and PLB:PLB membrane complexes. PLB subunit exchange from the PLB:SERCA regulatory complex was rapid, showing diffusion-limited FTR (tau=1.4 second). Conversely, PLB:PLB oligomeric complexes were found to be stable on a much longer time scale. Despite free lateral diffusion in the membrane, they showed no FTR over 80 seconds. Mutation of PLB position 40 from isoleucine to alanine (I40A-PLB) did not abolish PLB:PLB energy transfer, but destabilization of the PLB:PLB complex was apparent from an increased FTR rate (tau=8.4 seconds). Oligomers of I40A-PLB were stabilized by oxidative crosslinking of transmembrane cysteines with diamide. We conclude that PLB exchanges rapidly from its regulatory complex with the SERCA pump, whereas subunit exchange from the PLB oligomeric complex is slow and does not occur on the time scale of the cardiac cycle. 相似文献
999.
1000.
Adherence to Antiretroviral Therapy Assessed by Unannounced Pill Counts Conducted by Telephone 下载免费PDF全文
Kalichman SC Amaral CM Stearns H White D Flanagan J Pope H Cherry C Cain D Eaton L Kalichman MO 《Journal of general internal medicine》2007,22(7):1003-1006
BACKGROUND: Unannounced pill counts conducted in patients' homes is a valid objective method for monitoring medication adherence that is unfortunately costly and often impractical. Conducting unannounced pill counts by telephone may be a viable alternative for objectively assessing medication adherence. PURPOSE: To test an unannounced pill count assessment of adherence conducted by telephone. METHODS: HIV-positive men and women (N = 77) in Atlanta GA completed an unannounced telephone-based pill count immediately followed by a pill count conducted in an unannounced home visit. RESULTS: A high degree of concordance was observed between phone and home-based number of pills counted (Intraclass correlation, ICC = .997, 95% CI .995-.998, P < .001) and percent of pills taken (ICC = .990, 95% CI .986-.992, P < .001). Concordance between adherence above/below 90% and phone/home counts was 95%, Kappa coefficient = .995. Concordance between pill counts was not influenced by participant education or health literacy and was maintained when the data were censored to remove higher levels of adherence. Analyses of discordant pill counts found the most common source of error resulted from overcounted doses in pillboxes on the telephone. CONCLUSIONS: Unannounced phone-based pill counts offer an economically and logistically feasible objective method for monitoring medication adherence. 相似文献