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71.
WW Brooks OH Bing CH Conrad L O'Neill MT Crow EG Lakatta DE Dostal KM Baker MO Boluyt 《Canadian Metallurgical Quarterly》1997,30(6):1362-1368
The spontaneously hypertensive rat (SHR) exhibits a transition from stable compensated left ventricular (LV) hypertrophy to heart failure (HF) at a mean age of 21 months that is characterized by a decrease in alpha-myosin heavy chain (alpha-MHC) gene expression and increases in the expression of the atrial natriuretic factor (ANF), pro-alpha1(III) collagen, and transforming growth factor beta1 (TGF-beta1) genes. We tested the hypotheses that angiotensin-converting enzyme inhibition (ACEI) in SHR would prevent and reverse HF-associated changes in gene expression when administered prior to and after the onset of HF, respectively. We also investigated the effect of ACEI on circulating and cardiac components of the renin-angiotensin system. ACEI (captopril 2 g/L in the drinking water) was initiated at 12, 18, and 21 months of age in SHR without HF and in SHR with HF. Results were compared with those of age-matched normotensive Wistar-Kyoto (WKY) rats, and to untreated SHR with and without evidence of HF. ACEI initiated prior to failure prevented the changes in alpha-MHC, ANF, pro-alpha1(III) collagen, and TGF-beta1 gene expression that are associated with the transition to HF. ACEI initiated after the onset of HF lowered levels of TGF-beta1 mRNA by 50% (P<.05) and elevated levels of alpha-MHC mRNA two- to threefold (P<.05). Circulating levels of renin and angiotensin I were elevated four- to sixfold by ACEI, but surprisingly, plasma levels of angiotensin II were not reduced. ACEI increased LV renin mRNA levels in WKY and SHR by two- to threefold but did not influence LV levels of angiotensinogen mRNA. The results suggest that the anti-HF benefits of ACEI in SHR may be mediated, at least in part, by effects on the expression of specific genes, including those encoding alpha-MHC, ANF, TGF-beta1, pro-alpha1(III) collagen, and renin-angiotensin system components. 相似文献
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Transgene expression of bcl-xL permits anti-immunoglobulin (Ig)-induced proliferation in xid B cells
N Solvason WW Wu N Kabra F Lund-Johansen MG Roncarolo TW Behrens DA Grillot G Nunez E Lees M Howard 《Canadian Metallurgical Quarterly》1998,187(7):1081-1091
Mutations in the tyrosine kinase, Btk, result in a mild immunodeficiency in mice (xid). While B lymphocytes from xid mice do not proliferate to anti-immunoglobulin (Ig), we show here induction of the complete complement of cell cycle regulatory molecules, though the level of induction is about half that detected in normal B cells. Cell cycle analysis reveals that anti-Ig stimulated xid B cells enter S phase, but fail to complete the cell cycle, exhibiting a high rate of apoptosis. This correlated with a decreased ability to induce the anti-apoptosis regulatory protein, Bcl-xL. Ectopic expression of Bcl-xL in xid B cells permitted anti-Ig induced cell cycle progression demonstrating dual requirements for induction of anti-apoptotic proteins plus cell cycle regulatory proteins during antigen receptor mediated proliferation. Furthermore, our results link one of the immunodeficient traits caused by mutant Btk with the failure to properly regulate Bcl-xL. 相似文献
74.
HS Matloub WW Dzwierzynski S Erickson JR Sanger NJ Yousif V Muoneke 《Canadian Metallurgical Quarterly》1996,21(3):451-455
This study was undertaken to determine the usefulness of magnetic resonance imaging (MRI) in the diagnosis of flexor tendon rupture in patients who had prior surgery. Magnetic resonance imaging scans were performed on 11 digits (16 tendons) with the clinical diagnosis of flexor tendon rupture. Clinical suspicion correlated with MRI and surgical findings. Clinical examination yielded a 60% accuracy in diagnosis. MRI differentiated rupture from adhesions with a 100% accuracy rate. The MRI scan is a valuable tool in diagnosing tendon ruptures and may help reduce the incidence of unnecessary tendon explorations. 相似文献
75.
CJ Newschaffer C Laine WW Hauck T Fanning BJ Turner 《Canadian Metallurgical Quarterly》1998,75(1):153-169
The purpose of this study was to develop a substantive grounded theory of courage among middle-aged adults with long-term health concerns. Twenty-five persons from rural and non-metropolitan areas of Central Illinois were selected to participate in this study based on theoretical sampling procedures. Interviews of 1 to 2 hours using openended questions were audiotaped and transcribed verbatim. The data were analysed using grounded theory methods. Courage among middle-aged adults with long-term health concerns was determined to consist of an ongoing progressive-regressive process of becoming and being courageous. Being courageous involves being fully aware of and accepting the threat of a long-term health concern, solving problems using discernment, and developing enhanced sensitivities to personal needs and the world in general. Courageous behaviour consists of taking responsibility and being productive. Courage is not limitless, and the process of becoming and being courageous is dependent on intrapersonal and interpersonal factors. Health-care providers facilitate this process by demonstrating competence and communicating effectively. Outcomes of being courageous include personal integrity and thriving in the midst of normality. 相似文献
76.
WW Gibbs 《Canadian Metallurgical Quarterly》1998,278(6):26-27
Eight children with the cyst of choledochus, ageing from 1 month to 15 years, were treated for the period of 20 years in clinic. Cystoduodenostomy is the method of choice for the treatment. All the patients have recovered. 相似文献
77.
NJ Yousif WW Dzwierzynski JR Sanger HS Matloub 《Canadian Metallurgical Quarterly》1998,102(7):2431-2435
This case report describes the use of a single lateral arm flap sequentially transferred to two defects in a bilateral hand injury. We believe this is a novel approach in reconstructing defects in bilateral hands when a staged reconstruction is planned. 相似文献
78.
79.
The structure of the domain from simian virus 40 (SV40) large T-antigen that binds to the SV40 origin of DNA replication (T-ag-OBD131-260) has been determined by nuclear magnetic resonance spectroscopy. The overall fold, consisting of a central five-stranded antiparallel beta-sheet flanked by two alpha-helices on one side and one alpha-helix and one 3(10)-helix on the other, is a new one. Previous mutational analyses have identified two elements, termed A (approximately 152-155) and B2 (203-207), as essential for origin-specific recognition. These elements form two closely juxtaposed loops that define a continuous surface on the protein. The addition of a duplex oligonucleotide containing the origin recognition pentanucleotide GAGGC induces chemical shift changes and slows amide proton exchange in resonances from this region, indicating that this surface directly contacts the DNA. 相似文献
80.