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Lewis Andrew J. M. Rayner Jennifer J. Abdesselam Ines Neubauer Stefan Rider Oliver J. 《The international journal of cardiovascular imaging》2021,37(7):2277-2281
The International Journal of Cardiovascular Imaging - Obesity is associated with the development of left ventricular (LV) hypertrophy. Whether obesity in in the absence of comorbidities can cause... 相似文献
34.
Drenjancevic-Peric I Greene AS Kunert MP Lombard JH 《Microcirculation (New York, N.Y. : 1994)》2004,11(8):669-677
OBJECTIVES: Angiotensin II suppression leads to impaired vascular relaxation in normotensive animals on a high-salt diet. The goal of this study was to determine whether normal vascular reactivity could be restored by transferring the chromosomal region carrying the Dahl salt-resistant (R) renin gene into the Dahl salt-sensitive (SS) genetic background in a strain of renin congenic rats (RGRR). METHODS: Male RGRR and SS rats were fed low-salt (0.4%) and high-salt (4%) diets for 4 weeks. The responses of cremaster muscle arterioles to acetylcholine (ACh), sodium nitroprusside (SNP), and elevated PO2 were assessed using video microscopy. RESULTS: ACh-induced dilation was significantly enhanced in RGRR on a high-salt diet compared to SS rats, while dilation to the NO donor SNP was similar in both strains. A high-salt diet significantly enhanced arteriolar constriction in response to elevated PO2, in both SS and RGRR rats. CONCLUSIONS: These data suggest that transfer of the chromosomal region containing the renin gene is crucial in the recovery of ACh-induced dilation of arterioles in RGRR rats vs. SS rats, and that factors in the SS genetic background contribute to an enhanced sensitivity to elevated PO2, independent of genes on chromosome 13. 相似文献
35.
Antibodies to ribosomal P proteins of Trypanosoma cruzi in Chagas disease possess functional autoreactivity with heart tissue and differ from anti-P autoantibodies in lupus 下载免费PDF全文
Dan Kaplan Ines Ferrari Pablo Lopez Bergami Evelina Mahler Gabriela Levitus Pablo Chiale Johan Hoebeke Marc H. V. Van Regenmortel Mariano J. Levin 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(19):10301-10306
Anti-P antibodies present in sera from patients with chronic Chagas heart disease (cChHD) recognize peptide R13, EEEDDDMGFGLFD, which encompasses the C-terminal region of the Trypanosoma cruzi ribosomal P1 and P2 proteins. This peptide shares homology with the C-terminal region (peptide H13 EESDDDMGFGLFD) of the human ribosomal P proteins, which is in turn the target of anti-P autoantibodies in systemic lupus erythematosus (SLE), and with the acidic epitope, AESDE, of the second extracellular loop of the β1-adrenergic receptor. Anti-P antibodies from chagasic patients showed a marked preference for recombinant parasite ribosomal P proteins and peptides, whereas anti-P autoantibodies from SLE reacted with human and parasite ribosomal P proteins and peptides to the same extent. A semi-quantitative estimation of the binding of cChHD anti-P antibodies to R13 and H13 using biosensor technology indicated that the average affinity constant was about 5 times higher for R13 than for H13. Competitive enzyme immunoassays demonstrated that cChHD anti-P antibodies bind to the acidic portions of peptide H13, as well as to peptide H26R, encompassing the second extracellular loop of the β1 adrenoreceptor. Anti-P antibodies isolated from cChHD patients exert a positive chronotropic effect in vitro on cardiomyocytes from neonatal rats, which resembles closely that of anti-β1 receptor antibodies isolated from the same patient. In contrast, SLE anti-P autoantibodies have no functional effect. Our results suggest that the adrenergic-stimulating activity of anti-P antibodies may be implicated in the induction of functional myocardial impairments observed in cChHD. 相似文献
36.
Shear stress-induced up-regulation of the intermediate-conductance Ca(2+)-activated K(+) channel in human endothelium 总被引:3,自引:0,他引:3
Brakemeier S Kersten A Eichler I Grgic I Zakrzewicz A Hopp H Köhler R Hoyer J 《Cardiovascular research》2003,60(3):488-496
OBJECTIVE: Wall shear stress associated with blood flow is a major stimuli for generation of endothelial vasodilating and antithrombotic factors and it also regulates endothelial gene expression. Activation of endothelial intermediate-conductance Ca(2+)-activated K(+) channels (IK(Ca)) is important for the control of endothelial function by inducing cell hyperpolarization and thus generation of the endothelium-derived hyperpolarizing factor. In the present study we tested whether the IK(Ca) encoding IKCa1 gene is regulated by laminar shear stress (LSS). METHODS: Human umbilical vein endothelial cells (HUVEC) were subjected to LSS with a magnitude of 0.5-15 dyn/cm(2) and time intervals of 2-24 h in a flow cone apparatus. Expression of the IKCa1 gene and IK(Ca)-functions were determined by using real time RT-PCR and patch-clamp techniques. RESULTS: A short 2-4 h-or long 24 h-exposure to a LSS with a low (venous) magnitude of 0.5 dyn/cm(2) had no effect on IKCa1 expression levels. An exposure for 2 and 4 h to LSS with an intermediate magnitude of 5 dyn/cm(2) was also ineffective, whereas an exposure for 24 h induced a significant threefold up-regulation of IKCa1 expression levels. An exposure to LSS with a higher (arterial) magnitude of 15 dyn/cm(2), resulted in an eightfold up-regulation of IKCa1 expression levels after a 4 h-exposure and a fourfold increase of IKCa1 expression levels at 24 h. The increased IKCa1 expression levels following exposure to high levels of LSS resulted in enhanced IK(Ca) whole-cell currents and in an increased hyperpolarization of the endothelium in response to ATP and the IK(Ca) opener 1-EBIO. Inhibition of the mitogen-activated protein kinase/extracellular-signal-regulated kinase (ERK) kinase 1/2 (MEK/ERK) pathway by PD98059 prevented the LSS-induced up-regulation of IKCa1 expression levels and IK(Ca) whole-cell currents indicating that augmentation of IKCa1 expression levels is mediated by the LSS-induced activation of the MEK/ERK pathway. CONCLUSION: Long term exposure to LSS up-regulates expression and function of endothelial IK(Ca). This increase might represent a new important mechanism in endothelial adaptation to altered hemodynamics. 相似文献
37.
Alessandro Desideri Lauro Cortigiani Alejandra Ines Christen Sebastian Coscarelli Dario Gregori Pierluigi Zanco Roman Komorovsky Jeroen J Bax 《Journal of the American College of Cardiology》2005,46(7):1264-1269
OBJECTIVES: The purpose of this study was to assess the determinants of mortality in a large group of patients with ischemic cardiomyopathy who are treated medically and the impact of the extent of viable tissue on prognosis. BACKGROUND: Whether the presence of viability drives mortality in patients with ischemic cardiomyopathy who are treated medically and whether the extent of viability is important are issues that are currently unclear. METHODS: Two hundred sixty-one patients with ischemic cardiomyopathy underwent positron emission tomography (PET) for assessment of viability. Prospective follow-up was obtained. RESULTS: Ninety-four patients were revascularized and 167 were not. The cardiac death rate was significantly less in the revascularized patients as compared with medically treated patients (13% vs. 24%, p < 0.05). In the revascularized patients, there was a trend toward better survival in patients with viable myocardium as compared with nonviable myocardium (3.5-year survival, 85% and 75% respectively, p = NS). In the medically treated group, age (hazard ratio [HR] 2.1, 95% confidence interval [CI] 1.2 to 3.7), presence of left bundle branch block (HR 3.4, 95% CI 1.6 to 7.2) and extent of perfusion-metabolism mismatch on PET (HR 1.36, 95% CI 1.1 to 1.6) predicted cardiac death during a median follow-up period of 2.1 years. The risk of cardiac death was not significantly increased when the extent of mismatch was < or =20% (HR 0.97, 95% CI 0.46 to 2.05) but was significantly increased when the extent of mismatch was >20% (HR 3.21, 95% CI 1.38 to 7.49). CONCLUSIONS: Medically treated patients with ischemic cardiomyopathy and large areas of viable myocardium on PET are at high risk for cardiac death. 相似文献
38.
Ines Mahmoud Aicha Ben Tekaya Mariem Sahli Maha Mahmoud Olfa Saidane Hana Sahli Rawdha Tekaya Leila Abdelmoula 《The Egyptian Rheumatologist》2018,40(2):145-147
Background
Septic arthritis of the costovertebral thoracic joint is a rare site infection. We report an isolated case of septic arthritis of the 10th costo-vertebral right joint with osteitis due to Staphylococcus aureus.Case presentation
A 59 year old Tunisian man presented with a 2 months history of dorsal spinal pain with fever, associated with asthenia, anorexia and loss of weight. There was a raised C-reactive protein (176 mg/L) and erythrocyte sedimentation rate (100 mm/1st h). Tests for tuberculosis and brucellosis were negative. In the present patient, the clinical symptoms were unspecific with lack of obvious predisposing factors. He had neither history of taking immunosuppressors nor of any disease indicative of immunodeficiency. Thoraco-abdominal computed tomography (CT) showed a lytic lesion centered on the 10th costo-vertebral right joint and histo-pathologic exam of the costo-vertebral puncture confirmed chronic active osteitis and bacteriologic culture allowed identifying methicillin-sensitive Staphylococcus aureus. The patient was treated with ciprofloxacin 1500 mg/day, associated with daily rifampin (20 mg/kg) for total treatment duration of 12 weeks after consulting infectious disease specialists. After a follow-up of 6 months, the patient remained asymptomatic and the markers of inflammation negative.Conclusion
Septic arthritis of costovertebral joints should be considered when a patient presents with back pain, fever and elevated inflammatory markers. The diagnosis of septic arthritis of costovertebral joints remain a challenge to clinicians. CT is important to confirm a diagnosis and guide costovertebral biopsy and culture. Early and appropriate antibiotic therapy is important for a required outcome. 相似文献39.
Detection of central venous catheter‐related bloodstream infections in haematooncological patients 下载免费PDF全文
40.
Carmen M. Martín-Navarro Atteneri López-Arencibia Ines Sifaoui María Reyes-Batlle Basilio Valladares Enrique Martínez-Carretero José E. Pi?ero Sutherland K. Maciver Jacob Lorenzo-Morales 《Antimicrobial agents and chemotherapy》2015,59(5):2817-2824
Members of the genus Acanthamoeba are facultative pathogens of humans, causing a sight-threatening keratitis and a life-threatening encephalitis. In order to treat those infections properly, it is necessary to target the treatment not only to the trophozoite but also to the cyst. Furthermore, it may be advantageous to avoid parasite killing by necrosis, which may induce local inflammation. We must also avoid toxicity of host tissue. Many drugs which target eukaryotes are known to induce programmed cell death (PCD), but this process is poorly characterized in Acanthamoeba. Here, we study the processes of programmed cell death in Acanthamoeba, induced by several drugs, such as statins and voriconazole. We tested atorvastatin, fluvastatin, simvastatin, and voriconazole at the 50% inhibitory concentrations (IC50s) and IC90s that we have previously established. In order to evaluate this phenomenon, we investigated the DNA fragmentation, one of the main characteristics of PCD, with quantitative and qualitative techniques. Also, the changes related to phosphatidylserine exposure on the external cell membrane and cell permeability were studied. Finally, because caspases are key to PCD pathways, caspase activity was evaluated in Acanthamoeba. All the drugs assayed in this study induced PCD in Acanthamoeba. To the best of our knowledge, this is the first study where PCD induced by drugs is described quantitatively and qualitatively in Acanthamoeba. 相似文献