GLORIA

GEOMAR Library Ocean Research Information Access

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Online Resource
    Online Resource
    Ovid Technologies (Wolters Kluwer Health) ; 2004
    In:  Circulation Vol. 110, No. 22 ( 2004-11-30), p. 3435-3443
    In: Circulation, Ovid Technologies (Wolters Kluwer Health), Vol. 110, No. 22 ( 2004-11-30), p. 3435-3443
    Abstract: Background— Prolongation of the action potential duration (APD) and decreased transient outward K + current ( I to ) have been consistently observed in cardiac hypertrophy. The relation between electrical remodeling and cardiac hypertrophy in vivo is unknown. Methods and Results— We studied rat hearts subjected to pressure overload by surgical ascending aortic stenosis (AS) and simultaneously infected these hearts with an adenovirus carrying either the Kv4.3 gene ( Ad.Kv4.3 ) or the β-galactosidase gene ( Ad.β-gal ). I to density was reduced and APD 50 was prolonged ( P 〈 0.05) in AS rats compared with sham rats. Kv4.2 and Kv4.3 expressions were decreased by 58% and 51%, respectively ( P 〈 0.05). AS rats infected with Ad.β-gal developed cardiac hypertrophy compared with sham rats, as assessed by cellular capacitance and heart weight–body weight ratio. Associated with the development of cardiac hypertrophy, the expression of calcineurin and its downstream transcription factor nuclear factor of activated T cells (NFAT) c1 was persistently increased by 47% and 36%, respectively ( P 〈 0.05) in AS myocytes infected with Ad.β-gal compared with sham myocytes. In vivo gene transfer of Kv4.3 in AS rats was shown to increase Kv4.3 expression, increase I to density, and shorten APD 50 by 1.6-fold, 5.3-fold, and 3.6-fold, respectively ( P 〈 0.05). Furthermore, AS rats infected with Ad.Kv4.3 showed significant reductions in calcineurin and NFAT expression. ( P 〈 0.05). Conclusions— Downregulation of I to , APD prolongation, and cardiac hypertrophy occur early after AS, and in vivo gene transfer of Kv4.3 can restore these electrical parameters and abrogate the hypertrophic response via the calcineurin pathway.
    Type of Medium: Online Resource
    ISSN: 0009-7322 , 1524-4539
    Language: English
    Publisher: Ovid Technologies (Wolters Kluwer Health)
    Publication Date: 2004
    detail.hit.zdb_id: 1466401-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    Online Resource
    Online Resource
    Elsevier BV ; 2006
    In:  Journal of Molecular and Cellular Cardiology Vol. 40, No. 5 ( 2006-05), p. 725-735
    In: Journal of Molecular and Cellular Cardiology, Elsevier BV, Vol. 40, No. 5 ( 2006-05), p. 725-735
    Type of Medium: Online Resource
    ISSN: 0022-2828
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2006
    detail.hit.zdb_id: 1469767-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    In: Journal of Molecular and Cellular Cardiology, Elsevier BV, Vol. 48, No. 6 ( 2010-06), p. 1169-1179
    Type of Medium: Online Resource
    ISSN: 0022-2828
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2010
    detail.hit.zdb_id: 1469767-1
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 4
    Online Resource
    Online Resource
    Springer Science and Business Media LLC ; 2002
    In:  Basic Research in Cardiology Vol. 97, No. S1 ( 2002-05), p. I136-I145
    In: Basic Research in Cardiology, Springer Science and Business Media LLC, Vol. 97, No. S1 ( 2002-05), p. I136-I145
    Type of Medium: Online Resource
    ISSN: 0300-8428 , 1435-1803
    RVK:
    RVK:
    Language: English
    Publisher: Springer Science and Business Media LLC
    Publication Date: 2002
    detail.hit.zdb_id: 1458470-0
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 5
    Online Resource
    Online Resource
    Elsevier BV ; 2006
    In:  Heart Rhythm Vol. 3, No. 5 ( 2006-5), p. S109-
    In: Heart Rhythm, Elsevier BV, Vol. 3, No. 5 ( 2006-5), p. S109-
    Type of Medium: Online Resource
    ISSN: 1547-5271
    Language: English
    Publisher: Elsevier BV
    Publication Date: 2006
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 6
    Online Resource
    Online Resource
    Springer Science and Business Media LLC ; 1998
    In:  European Journal of Applied Physiology Vol. 78, No. 2 ( 1998-6-1), p. 141-147
    In: European Journal of Applied Physiology, Springer Science and Business Media LLC, Vol. 78, No. 2 ( 1998-6-1), p. 141-147
    Type of Medium: Online Resource
    ISSN: 1439-6319 , 1439-6327
    Language: Unknown
    Publisher: Springer Science and Business Media LLC
    Publication Date: 1998
    detail.hit.zdb_id: 1459054-2
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 7
    Online Resource
    Online Resource
    American Physiological Society ; 2002
    In:  American Journal of Physiology-Heart and Circulatory Physiology Vol. 283, No. 3 ( 2002-09-01), p. H1157-H1168
    In: American Journal of Physiology-Heart and Circulatory Physiology, American Physiological Society, Vol. 283, No. 3 ( 2002-09-01), p. H1157-H1168
    Abstract: Transient outward K + current density ( I to ) has been shown to vary between different regions of the normal myocardium and to be reduced in heart disease. In this study, we measured regional changes in action potential duration (APD), I to , and intracellular Ca 2+ concentration ([Ca 2+ ] i ) transients of ventricular myocytes derived from the right ventricular free wall (RVW) and interventricular septum (SEP) 8 wk after myocardial infarction (MI). At +40 mV, I to density in sham-operated hearts was significantly higher ( P 〈 0.01) in the RVW (15.0 ± 0.8 pA/pF, n = 47) compared with the SEP (7.0 ± 1.1 pA/pF, n = 18). After MI, I to density was not reduced in SEP myocytes but was reduced ( P 〈 0.01) in RVW myocytes (8.7 ± 1.0 pA/pF, n = 26) to levels indistinguishable from post-MI SEP myocytes. These changes in I to density correlated with Kv4.2 (but not Kv4.3) protein expression. By contrast, Kv1.4 expression was significantly higher in the RVW compared with the SEP and increased significantly after MI in RVW. APD measured at 50% or 90% repolarization was prolonged, whereas peak [Ca 2+ ] i transients amplitude was higher in the SEP compared with the RVW in sham myocytes. These regional differences in APD and [Ca 2+ ] i transients were eliminated by MI. Our results demonstrate that the significant regional differences in I to density, APD, and [Ca 2+ ] i between RVW and SEP are linked to a variation in Kv4.2 expression, which largely disappears after MI.
    Type of Medium: Online Resource
    ISSN: 0363-6135 , 1522-1539
    RVK:
    Language: English
    Publisher: American Physiological Society
    Publication Date: 2002
    detail.hit.zdb_id: 1477308-9
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 8
    In: Canadian Journal of Kidney Health and Disease, SAGE Publications, Vol. 7 ( 2020-01), p. 205435811989722-
    Abstract: Atypical hemolytic uremic syndrome (aHUS) is an extremely rare, heterogeneous disease of uncontrolled activation of the alternative complement pathway that is difficult to diagnose. We have evaluated the Canadian patients enrolled in the Global aHUS Registry to provide a Canadian perspective regarding the diagnosis and management of aHUS and the specific challenges faced. Objective: To evaluate Canadian patients enrolled in the Global aHUS Registry to provide a Canadian perspective regarding the diagnosis and management of aHUS and the specific challenges faced. Methods: The Global aHUS Registry is an observational, noninterventional, multicenter study that has prospectively and retrospectively collected data from patients of all ages with an investigator-made clinical diagnosis of aHUS, irrespective of treatment. Patients of all ages with a clinical diagnosis of aHUS were eligible and invited for enrollment, and those with evidence of Shiga toxin–producing Escherichia coli infection, or with ADAMTS13 activity ≤10%, or a subsequent diagnosis of thrombotic thrombocytopenic purpura were excluded. Data were collected at enrollment and every 6 months thereafter and were analyzed descriptively for categorical and continuous variables. End-stage renal disease (ESRD)-free survival was evaluated using Kaplan-Meier estimates, and ESRD-associated risk factors of interest were assessed using Cox proportional hazards regression models. Patients were censored at start of eculizumab for any outcome measures. Results: A total of 37 Canadian patients were enrolled (15 pediatric and 22 adult patients) between February 2014 and May 2017; the median age at initial aHUS presentation was 25.9 (interquartile range = 6.7-51.7) years; 62.2% were female and 94.6% had no family history of aHUS. Over three-quarters of patients (78.4%) had no conclusive genetic or anti-complement factor H (CFH) antibody information available, and most patients (94%) had no reported precipitating factors prior to aHUS diagnosis. Nine patients (8 adults and 1 child) experienced ESRD prior to the study. After initial presentation, there appears to be a trend that children are less likely to experience ESRD than adults, with 5-year ESRD-free survival of 93 and 56% ( P = .05) in children and adults, respectively. Enrolling physicians reported renal manifestations in all patients at initial presentation, and 68.4% of patients during the chronic phase (study entry ≥6 months after initial presentation). Likewise, extrarenal manifestations also occurred in more patients during the initial presenting phase than the chronic phase, particularly for gastrointestinal (61.1% vs 15.8%) and central nervous system sites (38.9% vs 5.3%). Fewer children than adults experienced gastrointestinal manifestations (50.0% vs 70.0%), but more children than adults experienced pulmonary manifestations (37.5% vs 10.0%). Conclusions: This evaluation provides insight into the diagnosis and management of aHUS in Canadian patients and the challenges faced. More genetic or anti-CFH antibody testing is needed to improve the diagnosis of aHUS, and the management of children and adults needs to consider several factors such as the risk of progression to ESRD is based on age (more likely in adults), and that the location of extrarenal manifestations differs in children and adults.
    Type of Medium: Online Resource
    ISSN: 2054-3581 , 2054-3581
    Language: English
    Publisher: SAGE Publications
    Publication Date: 2020
    detail.hit.zdb_id: 2765462-X
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 9
    Online Resource
    Online Resource
    American Physiological Society ; 2000
    In:  American Journal of Physiology-Heart and Circulatory Physiology Vol. 278, No. 4 ( 2000-04-01), p. H1105-H1116
    In: American Journal of Physiology-Heart and Circulatory Physiology, American Physiological Society, Vol. 278, No. 4 ( 2000-04-01), p. H1105-H1116
    Abstract: Previous studies have established that reductions in repolarizing currents occur in heart disease and can contribute to life-threatening arrhythmias in myocardium. In this study, we investigated whether the thyroid hormone analog 3,5-diiodothyropropionic acid (DITPA) could restore repolarizing transient outward K + current ( I to ) density and gene expression in rat myocardium after myocardial infarction (MI). Our findings show that I to density was reduced after MI (14.0 ± 1.0 vs. 10.2 ± 0.9 pA/pF, sham vs. post-MI at +40 mV). mRNA levels of Kv4.2 and Kv4.3genes were decreased but Kv1.4 mRNA levels were increased post-MI. Corresponding changes in Kv4.2 and Kv1.4 protein were also observed. Chronic treatment of post-MI rats with 10 mg/kg DITPA restored I to density (to 15.2 ± 1.1 pA/pF at +40 mV) as well as Kv4.2 and Kv1.4 expression to levels observed in sham-operated controls. Other membrane currents (Na + , L-type Ca 2+ , sustained, and inward rectifier K + currents) were unaffected by DITPA treatment. Associated with the changes in I to expression, action potential durations (current-clamp recordings in isolated single right ventricular myocytes and monophasic action potential recordings from the right free wall in situ) were prolonged after MI and restored with DITPA treatment. Our results demonstrate that DITPA restores I to density in the setting of MI, which may be useful in preventing complications associated with I to downregulation.
    Type of Medium: Online Resource
    ISSN: 0363-6135 , 1522-1539
    RVK:
    Language: English
    Publisher: American Physiological Society
    Publication Date: 2000
    detail.hit.zdb_id: 1477308-9
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 10
    Online Resource
    Online Resource
    Wiley ; 2001
    In:  The Journal of Physiology Vol. 533, No. 1 ( 2001-05), p. 201-214
    In: The Journal of Physiology, Wiley, Vol. 533, No. 1 ( 2001-05), p. 201-214
    Abstract: Action potential (AP) prolongation typically occurs in heart disease due to reductions in transient outward potassium currents ( I to ), and is associated with increased Ca 2+ transients. We investigated the underlying mechanisms responsible for enhanced Ca 2+ transients in normal isolated rat ventricular myocytes in response to the AP changes that occur following myocardial infarction. Normal myocytes stimulated with a train of long post‐myocardial infarction (MI) APs showed a 2.2‐fold elevation of the peak Ca 2+ transient and a 2.7‐fold augmentation of fractional cell shortening, relative to myocytes stimulated with a short control AP. The steady‐state Ca 2+ load of the sarcoplasmic reticulum (SR) was increased 2.0‐fold when myocytes were stimulated with trains of long post‐MI APs (111 ± 21.6 μmol l −1 ) compared with short control APs (56 ± 7.2 μmol l −1 ). Under conditions of equal SR Ca 2+ load, long post‐MI APs still resulted in a 1.7‐fold increase in peak [Ca 2+ ] i and a 3.8‐fold increase in fractional cell shortening relative to short control APs, establishing that changes in the triggering of SR Ca 2+ release are largely responsible for elevated Ca 2+ transients following AP prolongation. Fractional SR Ca 2+ release calculated from the measured SR Ca 2+ load and the integrated SR Ca 2+ fluxes was 24 ± 3 and 11 ± 2 % following post‐MI and control APs, respectively. The fractional release (FR) of Ca 2+ from the SR divided by the integrated L‐type Ca 2+ flux (FR/∫ F Ca,L ) was increased 1.2‐fold by post‐MI APs compared with control APs. Similar increases in excitation‐contraction (E‐C) coupling gains were observed establishing enhanced E‐C coupling efficiency. Our findings demonstrate that AP prolongation alone can markedly enhance E‐C coupling in normal myocytes through increases in the L‐type Ca 2+ current ( I Ca,L ) trigger combined with modest enhancements in Ca 2+ release efficiency. We propose that such changes in AP profile in diseased myocardium may contribute significantly to alterations in E‐C coupling independent of other biochemical or genetic changes.
    Type of Medium: Online Resource
    ISSN: 0022-3751 , 1469-7793
    URL: Issue
    RVK:
    Language: English
    Publisher: Wiley
    Publication Date: 2001
    detail.hit.zdb_id: 1475290-6
    SSG: 12
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...