Abelson tyrosine-protein kinase 2 Regulates Myoblast Proliferation and Controls Muscle Fiber Length

OpenAIRE

Burden, Steven; Lee, Jennifer

2017-01-01

Muscle fiber length is nearly uniform within a muscle but widely different among muscles. Here, we show that Abelson tyrosine-protein kinase 2 (Abl2) has a key role in regulating myofiber length, as a loss of Abl2 leads to excessively long myofibers in the diaphragm and other muscles. Increased myofiber length is caused by enhanced myoblast proliferation, expanding the pool of available myoblasts and leading to increased myoblast fusion. Abl2 acts in myoblasts, but expansion of the diaphragm ...

FSHD myoblasts fail to downregulate intermediate filament protein vimentin during myogenic differentiation.

Directory of Open Access Journals (Sweden)

Lipinski M.

2011-10-01

Full Text Available Facioscapulohumeral muscular dystrophy (FSHD is an autosomal dominant hereditary neuromuscular disorder. The clinical features of FSHD include weakness of the facial and shoulder girdle muscles followed by wasting of skeletal muscles of the pelvic girdle and lower extremities. Although FSHD myoblasts grown in vitro can be induced to differentiate into myotubes by serum starvation, the resulting FSHD myotubes have been shown previously to be morphologically abnormal. Aim. In order to find the cause of morphological anomalies of FSHD myotubes we compared in vitro myogenic differentiation of normal and FSHD myoblasts at the protein level. Methods. We induced myogenic differentiation of normal and FSHD myoblasts by serum starvation. We then compared protein extracts from proliferating myoblasts and differentiated myotubes using SDS-PAGE followed by mass spectrometry identification of differentially expressed proteins. Results. We demonstrated that the expression of vimentin was elevated at the protein and mRNA levels in FSHD myotubes as compared to normal myotubes. Conclusions. We demonstrate for the first time that in contrast to normal myoblasts, FSHD myoblasts fail to downregulate vimentin after induction of in vitro myogenic differentiation. We suggest that vimentin could be an easily detectable marker of FSHD myotubes

One-Step Purification of Human Skeletal Muscle Myoblasts and Subsequent Expansion Using Laminin-Coated Surface.

Science.gov (United States)

Chowdhury, Shiplu Roy; binti Ismail, Annis; Chee, Sia Chye; bin Laupa, Mohd Suffian; binti Jaffri, Fadhlun; Saberi, Salfarina Ezrina Mohmad; Idrus, Ruszymah Bt Hj

2015-11-01

Skeletal myoblasts have been extensively used to study muscle growth and differentiation, and were recently tested for their application as cell therapy and as a gene delivery system to treat muscle and nonmuscle diseases. However, contamination of fibroblasts in isolated cells from skeletal muscle is one of the long-standing problems for routine expansion. This study aimed to establish a simple one-step process to purify myoblasts and maintain their purity during expansion. Mixed cells were preplated serially on laminin- and collagen type I-coated surfaces in a different array for 5, 10, and 15 min. Immunocytochemical staining with antibodies specific to myoblasts was performed to evaluate myoblast attachment efficiency, purity, and yield. It was found that laminin-coated surface favors the attachment of myoblasts. Highest myoblast purity of 78.9% ± 6.8% was achieved by 5 min of preplating only on the laminin-coated surface with a yield of 56.9% ± 3.3%. Primary cells, isolated from skeletal muscle (n = 4), confirm the enhancement of purity through preplating on laminin-coated surface for 5 min. Subsequent expansion after preplating enhanced myoblast purity due to an increase in myoblast growth than fibroblasts. Myoblast purity of ∼ 98% was achieved when another preplating was performed during passaging. In conclusion, myoblasts can be purified and efficiently expanded in one step by preplating on laminin-coated surface, which is a simple and robust technique.

The critical role of myostatin in differentiation of sheep myoblasts

Energy Technology Data Exchange (ETDEWEB)

Liu, Chenxi [College of Life Science and Technology, Xinjiang University, Urumqi (China); Xinjiang Laboratory of Animal Biotechnology, Urumqi (China); Li, Wenrong; Zhang, Xuemei; Zhang, Ning; He, Sangang; Huang, Juncheng [Xinjiang Laboratory of Animal Biotechnology, Urumqi (China); Laboratory of Grass-fed Animal Genetics, Breeding and Reproduction of Ministry of Agriculture, Urumqi (China); Animal Biotechnological Research Center, Xinjiang Academy of Animal Science, Urumqi (China); Ge, Yubin [The State Engineering Laboratory of AIDS Vaccine, College of Life Science, Jilin University, Changchun (China); Liu, Mingjun, E-mail: xjlmj2004@yahoo.com.cn [Xinjiang Laboratory of Animal Biotechnology, Urumqi (China); Laboratory of Grass-fed Animal Genetics, Breeding and Reproduction of Ministry of Agriculture, Urumqi (China); Animal Biotechnological Research Center, Xinjiang Academy of Animal Science, Urumqi (China)

2012-06-08

Highlights: Black-Right-Pointing-Pointer Identification of the effective and specific shRNA to knockdown MSTN. Black-Right-Pointing-Pointer Overexpression of MSTN reversibly suppressed myogenic differentiation. Black-Right-Pointing-Pointer shRNA knockdown of endogenous MSTN promoted ovine myoblast differentiation. Black-Right-Pointing-Pointer MSTN inhibits myogenic differentiation through down-regulation of MyoD and Myogenin and up-regulation of Smad3. Black-Right-Pointing-Pointer Provides a promise for the generation of transgenic sheep to improve meat productivity. -- Abstract: Myostatin [MSTN, also known as growth differentiation factor 8 (GDF8)], is an inhibitor of skeletal muscle growth. Blockade of MSTN function has been reported to result in increased muscle mass in mice. However, its role in myoblast differentiation in farm animals has not been determined. In the present study, we sought to determine the role of MSTN in the differentiation of primary sheep myoblasts. We found that ectopic overexpression of MSTN resulted in lower fusion index in sheep myoblasts, which indicated the repression of myoblast differentiation. This phenotypic change was reversed by shRNA knockdown of the ectopically expressed MSTN in the cells. In contrast, shRNA knockdown of the endogenous MSTN resulted in induction of myogenic differentiation. Additional studies revealed that the induction of differentiation by knocking down the ectopically or endogenously expressed MSTN was accompanied by up-regulation of MyoD and myogenin, and down-regulation of Smad3. Our results demonstrate that MSTN plays critical role in myoblast differentiation in sheep, analogous to that in mice. This study also suggests that shRNA knockdown of MSTN could be a potentially promising approach to improve sheep muscle growth, so as to increase meat productivity.

The critical role of myostatin in differentiation of sheep myoblasts

International Nuclear Information System (INIS)

Liu, Chenxi; Li, Wenrong; Zhang, Xuemei; Zhang, Ning; He, Sangang; Huang, Juncheng; Ge, Yubin; Liu, Mingjun

2012-01-01

Highlights: ► Identification of the effective and specific shRNA to knockdown MSTN. ► Overexpression of MSTN reversibly suppressed myogenic differentiation. ► shRNA knockdown of endogenous MSTN promoted ovine myoblast differentiation. ► MSTN inhibits myogenic differentiation through down-regulation of MyoD and Myogenin and up-regulation of Smad3. ► Provides a promise for the generation of transgenic sheep to improve meat productivity. -- Abstract: Myostatin [MSTN, also known as growth differentiation factor 8 (GDF8)], is an inhibitor of skeletal muscle growth. Blockade of MSTN function has been reported to result in increased muscle mass in mice. However, its role in myoblast differentiation in farm animals has not been determined. In the present study, we sought to determine the role of MSTN in the differentiation of primary sheep myoblasts. We found that ectopic overexpression of MSTN resulted in lower fusion index in sheep myoblasts, which indicated the repression of myoblast differentiation. This phenotypic change was reversed by shRNA knockdown of the ectopically expressed MSTN in the cells. In contrast, shRNA knockdown of the endogenous MSTN resulted in induction of myogenic differentiation. Additional studies revealed that the induction of differentiation by knocking down the ectopically or endogenously expressed MSTN was accompanied by up-regulation of MyoD and myogenin, and down-regulation of Smad3. Our results demonstrate that MSTN plays critical role in myoblast differentiation in sheep, analogous to that in mice. This study also suggests that shRNA knockdown of MSTN could be a potentially promising approach to improve sheep muscle growth, so as to increase meat productivity.

Identification of gene expression modifications in myostatin-stimulated myoblasts

International Nuclear Information System (INIS)

Yang Wei; Zhang Yong; Ma Guoda; Zhao Xinyi; Chen Yan; Zhu Dahai

2005-01-01

Myostatin belongs to the transforming growth factor beta superfamily and has been shown to function as an inhibitor of skeletal muscle proliferation and differentiation. To gain insight into the molecular mechanisms of myostatin function during myogenesis, differential display reverse transcription PCR was employed to identify altered gene expressions associated with myostatin inhibitory function in chicken fetal myoblasts (CFMs). In this work, we have identified seven up-regulated and 12 down-regulated genes in myostatin stimulated CFMs. Those genes are involved in myogenic differentiation, cell architecture, energy metabolism, signal transduction, and apoptosis. The down-regulation of muscle creatine kinase B, troponin C, and myosin regulatory light chain is in agreement with the myostatin negative role in myocyte differentiation. In addition, the expression alteration of skeletal muscle-specific cardiac ankyrin repeat protein and the bcl-2 related anti-apoptotic protein Nr-13 suggests possible unique roles for myostatin in regulating myogenesis by controlling cofactors participated transcriptional regulation and apoptosis

Skeletal muscle myoblasts possess a stretch-responsive local angiotensin signalling system.

Science.gov (United States)

Johnston, Adam P W; Baker, Jeff; De Lisio, Michael; Parise, Gianni

2011-06-01

A paucity of information exists regarding the presence of local renin-angiotensin systems (RASs) in skeletal muscle and associated muscle stem cells. Skeletal muscle and muscle stem cells were isolated from C57BL/6 mice and examined for the presence of a local RAS using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR), immunohistochemistry (IHC), Western blotting and liquid chromatography-mass spectrometry (LC-MS). Furthermore, the effect of mechanical stimulation on RAS member gene expression was analysed. Whole skeletal muscle, primary myoblasts and C2C12 derived myoblasts and myotubes differentially expressed members of the RAS including angiotensinogen, angiotensin-converting enzyme (ACE), angiotensin II (Ang II) type 1 (AT(1)) and type 2 (AT(2)). Renin transcripts were never detected, however, mRNA for the 'renin-like' enzyme cathepsin D was observed and Ang I and Ang II were identified in cell culture supernatants from proliferating myoblasts. AT(1) appeared to co-localise with polymerised actin filaments in proliferating myoblasts and was primarily found in the nucleus of terminally differentiated myotubes. Furthermore, mechanical stretch of proliferating and differentiating C2C12 cells differentially induced mRNA expression of angiotensinogen, AT(1) and AT(2). Proliferating and differentiated muscle stem cells possess a local stress-responsive RAS in vitro. The precise function of a local RAS in myoblasts remains unknown. However, evidence presented here suggests that Ang II may be a regulator of skeletal muscle myoblasts.

Myomaker, Regulated by MYOD, MYOG and miR-140-3p, Promotes Chicken Myoblast Fusion

Directory of Open Access Journals (Sweden)

Wen Luo

2015-11-01

Full Text Available The fusion of myoblasts is an important step during skeletal muscle differentiation. A recent study in mice found that a transmembrane protein called Myomaker, which is specifically expressed in muscle, is critical for myoblast fusion. However, the cellular mechanism of its roles and the regulatory mechanism of its expression remain unclear. Chicken not only plays an important role in meat production but is also an ideal model organism for muscle development research. Here, we report that Myomaker is also essential for chicken myoblast fusion. Forced expression of Myomaker in chicken primary myoblasts promotes myoblast fusion, whereas knockdown of Myomaker by siRNA inhibits myoblast fusion. MYOD and MYOG, which belong to the family of myogenic regulatory factors, can bind to a conserved E-box located proximal to the Myomaker transcription start site and induce Myomaker transcription. Additionally, miR-140-3p can inhibit Myomaker expression and myoblast fusion, at least in part, by binding to the 3ʹ UTR of Myomaker in vitro. These findings confirm the essential roles of Myomaker in avian myoblast fusion and show that MYOD, MYOG and miR-140-3p can regulate Myomaker expression.

Analysis of differential lipofection efficiency in primary and established myoblasts.

Science.gov (United States)

Pampinella, Francesca; Lechardeur, Delphine; Zanetti, Elena; MacLachlan, Ian; Benharouga, Mohammed; Lukacs, Gergely L; Vitiello, Libero

2002-02-01

In this study we have compared the process of lipid-mediated transfection in primary and established myoblasts, in an attempt to elucidate the mechanisms responsible for the scarce transfectability of the former. We determined the metabolic stability of cytoplasmically injected and lipofected DNA in primary and established myoblasts and carried out a comparative time course analysis of luciferase reporter-gene expression and DNA stability. The efficiency of the transcription-translation machinery of the two cell types was compared by intranuclear injection of naked plasmid DNA encoding luciferase. Subcellular colocalization of fluorescein-labeled lipopolyplexes with specific endosomal and lysosomal markers was performed by confocal microscopy to monitor the intracellular trafficking of plasmid DNA during transfection. The metabolic stability of plasmid DNA was similar in primary and established myoblasts after both lipofection and cytoplasmic injection. In both cell types, lipofection had no detectable effect on the rate of cell proliferation. Confocal analysis showed that nuclear translocation of transfected DNA coincided with localization in a compartment devoid of endosome- or lysosome-specific marker proteins. The residency time of plasmid DNA in this compartment differed for primary and established myoblasts. Our findings suggest that the lower transfectability of primary myoblasts is mostly due to a difference in the intracellular delivery pathway that correlates with more rapid delivery of internalized complex to the lysosomal compartment.

Protection by 6-aminonicotinamide against oxidative stress in cardiac cells

DEFF Research Database (Denmark)

Hofgaard, Johannes P; Sigurdardottir, Kristin Sigridur; Treiman, Marek

2006-01-01

necrosis following global ischemia in an isolated rat heart, apparently by limiting the oxidative injury component. We therefore explored the antioxidative potential of 6AN in a model using H9C2(2-1) rat cardiac myoblasts exposed to H2O2 stress. Dependent on the specific protocol, 6AN pretreatment for 6...

[Human myoblast culture as muscle stem cells in medical and biological studies].

Science.gov (United States)

Terekhov, S M; Krokhina, T B; Shishkin, S S; Krakhmaleva, I N; Zakharov, S F; Ershova, E S

2001-01-01

The method for obtaining human myoblast culture has been modified to consider the specific histological localization of the satellite cells as well as their growth properties; the cultivation conditions have been selected to grow up to 150000 cells/cm2. At high densities, the cells remain mononuclear and preserve their typical myoblast morphology as well as the capacity for fusion and the formation of myotubes. By contrast to fibroblasts, up to 80% of the cells in the myoblast culture were positive in the acid phosphatase test, which indicates their stem nature. The obtained myoblast cultures were used in the clinical tests of cell-mediated gene therapy of Duchenne's muscular dystrophy as well as in the bioassay for the effects of biologically active compounds.

Elastic hydrogel substrate supports robust expansion of murine myoblasts and enhances their engraftment

International Nuclear Information System (INIS)

Ding, Ke; Yang, Zhong; Xu, Jian-zhong; Liu, Wen-ying; Zeng, Qiang; Hou, Fang; Lin, Sen

2015-01-01

The application of satellite cell-derived myoblasts in regenerative medicine has been restricted by the rapid loss of stemness during in vitro cell expansion using traditional culture systems. However, studies published in the past decade have highlighted the influence of substrate elasticity on stem cell fate and revealed that culture on a soft hydrogel substrate can promote self-renewal and prolong the regenerative potential of muscle stem cells. Whether hydrogel substrates have similar effects after long-term robust expansion remains to be determined. Herein we prepared an elastic chitosan/beta-glycerophosphate/collagen hydrogel mimicking the soft microenvironment of muscle tissues for use as the substrate for satellite cell culture and investigated its influence on long-term cell expansion. After 20 passages in culture, satellite cell-derived myoblasts cultured on our hydrogel substrate exhibited significant improvements in proliferation capability, cell viability, colony forming frequency, and potential for myogenic differentiation compared to those cultured on a routine rigid culture surface. Immunochemical staining and western blot analysis both confirmed that myoblasts cultured on the hydrogel substrate expressed higher levels of several differentiation-related markers, including Pax7, Pax3, and SSEA-1, and a lower level of MyoD compared to myoblasts cultured on rigid culture plates (all p<0.05). After transplantation into the tibialis anterior of nude mice, myoblasts that had been cultured on the hydrogel substrate demonstrated a significantly greater engraftment efficacy than those cultured on the traditional surface. Collectively, these results indicate that the elastic hydrogel substrate supported robust expansion of murine myoblasts and enhanced their engraftment in vivo. - Highlights: • An elastic hydrogel was designed to mimic the pliable muscle tissue microenvironment. • Myoblasts retained their stemness in long-term culture on the elastic

Elastic hydrogel substrate supports robust expansion of murine myoblasts and enhances their engraftment

Energy Technology Data Exchange (ETDEWEB)

Ding, Ke, E-mail: dk1118@yeah.net [Department of Pediatric Surgery, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, Chengdu 610072 (China); Yang, Zhong [Department of Clinical Hematology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Xu, Jian-zhong, E-mail: xjzspine@163.com [Department of Orthopaedics, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Liu, Wen-ying; Zeng, Qiang; Hou, Fang [Department of Pediatric Surgery, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, Chengdu 610072 (China); Lin, Sen [Department of Anatomy and Histology & Embryology, Chengdu Medical College, Chengdu 610500 (China)

2015-09-10

The application of satellite cell-derived myoblasts in regenerative medicine has been restricted by the rapid loss of stemness during in vitro cell expansion using traditional culture systems. However, studies published in the past decade have highlighted the influence of substrate elasticity on stem cell fate and revealed that culture on a soft hydrogel substrate can promote self-renewal and prolong the regenerative potential of muscle stem cells. Whether hydrogel substrates have similar effects after long-term robust expansion remains to be determined. Herein we prepared an elastic chitosan/beta-glycerophosphate/collagen hydrogel mimicking the soft microenvironment of muscle tissues for use as the substrate for satellite cell culture and investigated its influence on long-term cell expansion. After 20 passages in culture, satellite cell-derived myoblasts cultured on our hydrogel substrate exhibited significant improvements in proliferation capability, cell viability, colony forming frequency, and potential for myogenic differentiation compared to those cultured on a routine rigid culture surface. Immunochemical staining and western blot analysis both confirmed that myoblasts cultured on the hydrogel substrate expressed higher levels of several differentiation-related markers, including Pax7, Pax3, and SSEA-1, and a lower level of MyoD compared to myoblasts cultured on rigid culture plates (all p<0.05). After transplantation into the tibialis anterior of nude mice, myoblasts that had been cultured on the hydrogel substrate demonstrated a significantly greater engraftment efficacy than those cultured on the traditional surface. Collectively, these results indicate that the elastic hydrogel substrate supported robust expansion of murine myoblasts and enhanced their engraftment in vivo. - Highlights: • An elastic hydrogel was designed to mimic the pliable muscle tissue microenvironment. • Myoblasts retained their stemness in long-term culture on the elastic

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) activates promyogenic signaling pathways, thereby promoting myoblast differentiation

Energy Technology Data Exchange (ETDEWEB)

Lee, Sang-Jin; Go, Ga-Yeon; Yoo, Miran; Kim, Yong Kee [Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of); Seo, Dong-Wan [College of Pharmacy, Dankook University, Cheonan 330-714 (Korea, Republic of); Kang, Jong-Sun [Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Samsung Biomedical Research Institute, Suwon 440-746 (Korea, Republic of); Bae, Gyu-Un, E-mail: gbae@sookmyung.ac.kr [Research Center for Cell Fate Control, College of Pharmacy, Sookmyung Women' s University, Seoul 140-742 (Korea, Republic of)

2016-01-29

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) regulates postnatal myogenesis by alleviating myostatin activity, but the molecular mechanisms by which it regulates myogenesis are not fully understood. In this study, we investigate molecular mechanisms of PPARβ/δ in myoblast differentiation. C2C12 myoblasts treated with a PPARβ/δ agonist, GW0742 exhibit enhanced myotube formation and muscle-specific gene expression. GW0742 treatment dramatically activates promyogenic kinases, p38MAPK and Akt, in a dose-dependent manner. GW0742-stimulated myoblast differentiation is mediated by p38MAPK and Akt, since it failed to restore myoblast differentiation repressed by inhibition of p38MAPK and Akt. In addition, GW0742 treatment enhances MyoD-reporter activities. Consistently, overexpression of PPARβ/δ enhances myoblast differentiation accompanied by elevated activation of p38MAPK and Akt. Collectively, these results suggest that PPARβ/δ enhances myoblast differentiation through activation of promyogenic signaling pathways. - Highlights: • A PPARβ/δ agonist, GW0742 promotes myoblast differentiation. • GW0742 activates both p38MAPK and Akt activation in myogenic differentiation. • GW0742 enhances MyoD activity for myogenic differentiation. • Overexpression of PPARβ/δ enhances myoblast differentiation via activating promyogenic signaling pathways. • This is the first finding for agonistic mechanism of PPARβ/δ in myogenesis.

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) activates promyogenic signaling pathways, thereby promoting myoblast differentiation

International Nuclear Information System (INIS)

Lee, Sang-Jin; Go, Ga-Yeon; Yoo, Miran; Kim, Yong Kee; Seo, Dong-Wan; Kang, Jong-Sun; Bae, Gyu-Un

2016-01-01

Peroxisome proliferator-activated receptor β/δ (PPARβ/δ) regulates postnatal myogenesis by alleviating myostatin activity, but the molecular mechanisms by which it regulates myogenesis are not fully understood. In this study, we investigate molecular mechanisms of PPARβ/δ in myoblast differentiation. C2C12 myoblasts treated with a PPARβ/δ agonist, GW0742 exhibit enhanced myotube formation and muscle-specific gene expression. GW0742 treatment dramatically activates promyogenic kinases, p38MAPK and Akt, in a dose-dependent manner. GW0742-stimulated myoblast differentiation is mediated by p38MAPK and Akt, since it failed to restore myoblast differentiation repressed by inhibition of p38MAPK and Akt. In addition, GW0742 treatment enhances MyoD-reporter activities. Consistently, overexpression of PPARβ/δ enhances myoblast differentiation accompanied by elevated activation of p38MAPK and Akt. Collectively, these results suggest that PPARβ/δ enhances myoblast differentiation through activation of promyogenic signaling pathways. - Highlights: • A PPARβ/δ agonist, GW0742 promotes myoblast differentiation. • GW0742 activates both p38MAPK and Akt activation in myogenic differentiation. • GW0742 enhances MyoD activity for myogenic differentiation. • Overexpression of PPARβ/δ enhances myoblast differentiation via activating promyogenic signaling pathways. • This is the first finding for agonistic mechanism of PPARβ/δ in myogenesis.

Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells

Energy Technology Data Exchange (ETDEWEB)

Gao, Fei; Kishida, Tsunao; Ejima, Akika [Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto (Japan); Gojo, Satoshi [Department of Cardiac Support, Kyoto Prefectural University of Medicine, Kyoto (Japan); Mazda, Osam, E-mail: mazda@koto.kpu-m.ac.jp [Department of Immunology, Kyoto Prefectural University of Medicine, Kyoto (Japan)

2013-02-08

Highlights: ► iPS-derived cells express myostatin and its receptor upon myoblast differentiation. ► Myostatin inhibits myoblast differentiation by inhibiting MyoD and Myo5a induction. ► Silencing of myostatin promotes differentiation of human iPS cells into myoblasts. -- Abstract: Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases.

Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells

International Nuclear Information System (INIS)

Gao, Fei; Kishida, Tsunao; Ejima, Akika; Gojo, Satoshi; Mazda, Osam

2013-01-01

Highlights: ► iPS-derived cells express myostatin and its receptor upon myoblast differentiation. ► Myostatin inhibits myoblast differentiation by inhibiting MyoD and Myo5a induction. ► Silencing of myostatin promotes differentiation of human iPS cells into myoblasts. -- Abstract: Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases

Abelson tyrosine-protein kinase 2 regulates myoblast proliferation and controls muscle fiber length

OpenAIRE

Lee, Jennifer K; Hallock, Peter T; Burden, Steven J

2017-01-01

Muscle fiber length is nearly uniform within a muscle but widely different among different muscles. We show that Abelson tyrosine-protein kinase 2 (Abl2) has a key role in regulating myofiber length, as a loss of Abl2 leads to excessively long myofibers in the diaphragm, intercostal and levator auris muscles but not limb muscles. Increased myofiber length is caused by enhanced myoblast proliferation, expanding the pool of myoblasts and leading to increased myoblast fusion. Abl2 acts in myobla...

Group I Paks Promote Skeletal Myoblast Differentiation In Vivo and In Vitro

DEFF Research Database (Denmark)

Joseph, Giselle A; Lu, Min; Radu, Maria

2017-01-01

fusion in Drosophila We report that both Pak1 and Pak2 are activated during mammalian myoblast differentiation. One pathway of activation is initiated by N-cadherin ligation and involves the cadherin coreceptor Cdo with its downstream effector, Cdc42. Individual genetic deletion of Pak1 and Pak2 in mice....... Furthermore, primary myoblasts lacking Pak1 and Pak2 display delayed expression of myogenic differentiation markers and myotube formation. These results identify Pak1 and Pak2 as redundant regulators of myoblast differentiation in vitro and in vivo and as components of the promyogenic Ncad/Cdo/Cdc42 signaling...

Interactions between Skeletal Muscle Myoblasts and their Extracellular Matrix Revealed by a Serum Free Culture System.

Science.gov (United States)

Chaturvedi, Vishal; Dye, Danielle E; Kinnear, Beverley F; van Kuppevelt, Toin H; Grounds, Miranda D; Coombe, Deirdre R

2015-01-01

Decellularisation of skeletal muscle provides a system to study the interactions of myoblasts with muscle extracellular matrix (ECM). This study describes the efficient decellularisation of quadriceps muscle with the retention of matrix components and the use of this matrix for myoblast proliferation and differentiation under serum free culture conditions. Three decellularisation approaches were examined; the most effective was phospholipase A2 treatment, which removed cellular material while maximizing the retention of ECM components. Decellularised muscle matrices were then solubilized and used as substrates for C2C12 mouse myoblast serum free cultures. The muscle matrix supported myoblast proliferation and differentiation equally as well as collagen and fibronectin. Immunofluorescence analyses revealed that myoblasts seeded on muscle matrix and fibronectin differentiated to form long, well-aligned myotubes, while myoblasts seeded on collagen were less organized. qPCR analyses showed a time dependent increase in genes involved in skeletal muscle differentiation and suggested that muscle-derived matrix may stimulate an increased rate of differentiation compared to collagen and fibronectin. Decellularized whole muscle three-dimensional scaffolds also supported cell adhesion and spreading, with myoblasts aligning along specific tracts of matrix proteins within the scaffolds. Thus, under serum free conditions, intact acellular muscle matrices provided cues to direct myoblast adhesion and migration. In addition, myoblasts were shown to rapidly secrete and organise their own matrix glycoproteins to create a localized ECM microenvironment. This serum free culture system has revealed that the correct muscle ECM facilitates more rapid cell organisation and differentiation than single matrix glycoprotein substrates.

Live cell imaging reveals marked variability in myoblast proliferation and fate

Science.gov (United States)

2013-01-01

Background During the process of muscle regeneration, activated stem cells termed satellite cells proliferate, and then differentiate to form new myofibers that restore the injured area. Yet not all satellite cells contribute to muscle repair. Some continue to proliferate, others die, and others become quiescent and are available for regeneration following subsequent injury. The mechanisms that regulate the adoption of different cell fates in a muscle cell precursor population remain unclear. Methods We have used live cell imaging and lineage tracing to study cell fate in the C2 myoblast line. Results Analyzing the behavior of individual myoblasts revealed marked variability in both cell cycle duration and viability, but similarities between cells derived from the same parental lineage. As a consequence, lineage sizes and outcomes differed dramatically, and individual lineages made uneven contributions toward the terminally differentiated population. Thus, the cohort of myoblasts undergoing differentiation at the end of an experiment differed dramatically from the lineages present at the beginning. Treatment with IGF-I increased myoblast number by maintaining viability and by stimulating a fraction of cells to complete one additional cell cycle in differentiation medium, and as a consequence reduced the variability of the terminal population compared with controls. Conclusion Our results reveal that heterogeneity of responses to external cues is an intrinsic property of cultured myoblasts that may be explained in part by parental lineage, and demonstrate the power of live cell imaging for understanding how muscle differentiation is regulated. PMID:23638706

Role of an inward rectifier K+ current and of hyperpolarization in human myoblast fusion

Science.gov (United States)

Liu, J-H; Bijlenga, P; Fischer-Lougheed, J; Occhiodoro, T; Kaelin, A; Bader, C R; Bernheim, L

1998-01-01

The role of K+ channels and membrane potential in myoblast fusion was evaluated by examining resting membrane potential and timing of expression of K+ currents at three stages of differentiation of human myogenic cells: undifferentiated myoblasts, fusion-competent myoblasts (FCMBs), and freshly formed myotubes. Two K+ currents contribute to a hyperpolarization of myoblasts prior to fusion: IK(NI), a non-inactivating delayed rectifier, and IK(IR), an inward rectifier. IK(NI) density is low in undifferentiated myoblasts, increases in FCMBs and declines in myotubes. On the other hand, IK(IR) is expressed in 28 % of the FCMBs and in all myotubes. IK(IR) is reversibly blocked by Ba2+ or Cs+. Cells expressing IK(IR) have resting membrane potentials of −65 mV. A block by Ba2+ or Cs+ induces a depolarization to a voltage determined by IK(NI) (−32 mV). Cs+ and Ba2+ ions reduce myoblast fusion. It is hypothesized that the IK(IR)-mediated hyperpolarization allows FCMBs to recruit Na+, K+ and T-type Ca2+ channels which are present in these cells and would otherwise be inactivated. FCMBs, rendered thereby capable of firing action potentials, could amplify depolarizing signals and may accelerate fusion. PMID:9705997

Myoblast replication is reduced in the IUGR fetus despite maintained proliferative capacity in vitro.

Science.gov (United States)

Soto, Susan M; Blake, Amy C; Wesolowski, Stephanie R; Rozance, Paul J; Barthel, Kristen B; Gao, Bifeng; Hetrick, Byron; McCurdy, Carrie E; Garza, Natalia G; Hay, William W; Leinwand, Leslie A; Friedman, Jacob E; Brown, Laura D

2017-03-01

Adults who were affected by intrauterine growth restriction (IUGR) suffer from reductions in muscle mass and insulin resistance, suggesting muscle growth may be restricted by molecular events that occur during fetal development. To explore the basis of restricted fetal muscle growth, we used a sheep model of progressive placental insufficiency-induced IUGR to assess myoblast proliferation within intact skeletal muscle in vivo and isolated myoblasts stimulated with insulin in vitro Gastrocnemius and soleus muscle weights were reduced by 25% in IUGR fetuses compared to those in controls (CON). The ratio of PAX7+ nuclei (a marker of myoblasts) to total nuclei was maintained in IUGR muscle compared to CON, but the fraction of PAX7+ myoblasts that also expressed Ki-67 (a marker of cellular proliferation) was reduced by 23%. Despite reduced proliferation in vivo, fetal myoblasts isolated from IUGR biceps femoris and cultured in enriched media in vitro responded robustly to insulin in a dose- and time-dependent manner to increase proliferation. Similarly, insulin stimulation of IUGR myoblasts upregulated key cell cycle genes and DNA replication. There were no differences in the expression of myogenic regulatory transcription factors that drive commitment to muscle differentiation between CON and IUGR groups. These results demonstrate that the molecular machinery necessary for transcriptional control of proliferation remains intact in IUGR fetal myoblasts, indicating that in vivo factors such as reduced insulin and IGF1, hypoxia and/or elevated counter-regulatory hormones may be inhibiting muscle growth in IUGR fetuses. © 2017 Society for Endocrinology.

Construction and Development of a Cardiac Tissue-Specific and Hypoxia-Inducible Expression Vector

Directory of Open Access Journals (Sweden)

Shahrooz Ghaderi

2018-03-01

Full Text Available Purpose: Cardiovascular gene therapy is a sophisticated approach, thanks to the safety of vectors, stable transgene expression, delivery method, and different layers of the heart. To date, numerous expression vectors have been introduced in biotechnology and biopharmacy industries in relation to genetic manipulation. Despite the rapid growth of these modalities, they must be intelligently designed, addressing the cardiac-specific transgene expression and less side effects. Herein, we conducted a pilot project aiming to design a cardiac-specific hypoxia-inducible expression cassette. Methods: We explored a new approach to design an expression cassette containing cardiac specific enhancer, hypoxia response elements (HRE, cardiac specific promoter, internal ribosome entry site (IRES, and beta globin poly A sequence to elicit specific and inducible expression of the gene of interest. Enhanced green fluorescent protein (eGFP was sub-cloned by BglII and NotI into the cassette. The specificity and inducible expression of the cassette was determined in both mouse myoblast C2C12 and mammary glandular tumor 4T1 as ‘twin’ cells. eGFP expression was evaluated by immunofluorescence microscope and flow cytometry at 520 nm emission peak. Results: Our data revealed that the designed expression cassette provided tissue specific and hypoxia inducible (O2<1% transgene expression. Conclusion: It is suggested that cardiac-specific enhancer combined with cardiac-specific promoter are efficient for myoblast specific gene expression. As well, this is for the first time that HRE are derived from three well known hypoxia-regulated promoters. Therefore, there is no longer need to overlap PCR process for one repeated sequence just in one promoter.

Molecular and immunohistochemical analyses of cardiac troponin T during cardiac development in the Mexican axolotl, Ambystoma mexicanum.

Science.gov (United States)

Zhang, C; Pietras, K M; Sferrazza, G F; Jia, P; Athauda, G; Rueda-de-Leon, E; Rveda-de-Leon, E; Maier, J A; Dube, D K; Lemanski, S L; Lemanski, L F

2007-01-01

The Mexican axolotl, Ambystoma mexicanum, is an excellent animal model for studying heart development because it carries a naturally occurring recessive genetic mutation, designated gene c, for cardiac nonfunction. The double recessive mutants (c/c) fail to form organized myofibrils in the cardiac myoblasts resulting in hearts that fail to beat. Tropomyosin expression patterns have been studied in detail and show dramatically decreased expression in the hearts of homozygous mutant embryos. Because of the direct interaction between tropomyosin and troponin T (TnT), and the crucial functions of TnT in the regulation of striated muscle contraction, we have expanded our studies on this animal model to characterize the expression of the TnT gene in cardiac muscle throughout normal axolotl development as well as in mutant axolotls. In addition, we have succeeded in cloning the full-length cardiac troponin T (cTnT) cDNA from axolotl hearts. Confocal microscopy has shown a substantial, but reduced, expression of TnT protein in the mutant hearts when compared to normal during embryonic development. 2006 Wiley-Liss, Inc.

HGF potentiates extracellular matrix-driven migration of human myoblasts: involvement of matrix metalloproteinases and MAPK/ERK pathway.

Science.gov (United States)

González, Mariela Natacha; de Mello, Wallace; Butler-Browne, Gillian S; Silva-Barbosa, Suse Dayse; Mouly, Vincent; Savino, Wilson; Riederer, Ingo

2017-10-10

The hepatocyte growth factor (HGF) is required for the activation of muscle progenitor cells called satellite cells (SC), plays a role in the migration of proliferating SC (myoblasts), and is present as a soluble factor during muscle regeneration, along with extracellular matrix (ECM) molecules. In this study, we aimed at determining whether HGF is able to interact with ECM proteins, particularly laminin 111 and fibronectin, and to modulate human myoblast migration. We evaluated the expression of the HGF-receptor c-Met, laminin, and fibronectin receptors by immunoblotting, flow cytometry, or immunofluorescence and used Transwell assays to analyze myoblast migration on laminin 111 and fibronectin in the absence or presence of HGF. Zymography was used to check whether HGF could modulate the production of matrix metalloproteinases by human myoblasts, and the activation of MAPK/ERK pathways was evaluated by immunoblotting. We demonstrated that human myoblasts express c-Met, together with laminin and fibronectin receptors. We observed that human laminin 111 and fibronectin have a chemotactic effect on myoblast migration, and this was synergistically increased when low doses of HGF were added. We detected an increase in MMP-2 activity in myoblasts treated with HGF. Conversely, MMP-2 inhibition decreased the HGF-associated stimulation of cell migration triggered by laminin or fibronectin. HGF treatment also induced in human myoblasts activation of MAPK/ERK pathways, whose specific inhibition decreased the HGF-associated stimulus of cell migration triggered by laminin 111 or fibronectin. We demonstrate that HGF induces ERK phosphorylation and MMP production, thus stimulating human myoblast migration on ECM molecules. Conceptually, these data state that the mechanisms involved in the migration of human myoblasts comprise both soluble and insoluble moieties. This should be taken into account to optimize the design of therapeutic cell transplantation strategies by improving

The Satellite Cell Niche Regulates the Balance between Myoblast Differentiation and Self-Renewal via p53.

Science.gov (United States)

Flamini, Valentina; Ghadiali, Rachel S; Antczak, Philipp; Rothwell, Amy; Turnbull, Jeremy E; Pisconti, Addolorata

2018-03-13

Satellite cells are adult muscle stem cells residing in a specialized niche that regulates their homeostasis. How niche-generated signals integrate to regulate gene expression in satellite cell-derived myoblasts is poorly understood. We undertook an unbiased approach to study the effect of the satellite cell niche on satellite cell-derived myoblast transcriptional regulation and identified the tumor suppressor p53 as a key player in the regulation of myoblast quiescence. After activation and proliferation, a subpopulation of myoblasts cultured in the presence of the niche upregulates p53 and fails to differentiate. When satellite cell self-renewal is modeled ex vivo in a reserve cell assay, myoblasts treated with Nutlin-3, which increases p53 levels in the cell, fail to differentiate and instead become quiescent. Since both these Nutlin-3 effects are rescued by small interfering RNA-mediated p53 knockdown, we conclude that a tight control of p53 levels in myoblasts regulates the balance between differentiation and return to quiescence. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

Short-hairpin Mediated Myostatin Knockdown Resulted in Altered Expression of Myogenic Regulatory Factors with Enhanced Myoblast Proliferation in Fetal Myoblast Cells of Goats.

Science.gov (United States)

Kumar, Rohit; Singh, Satyendra Pal; Mitra, Abhijit

2018-01-02

Myostatin (MSTN) is a well-known negative regulator of skeletal muscle development. Reduced expression due to natural mutations in the coding region and knockout as well as knockdown of MSTN results in an increase in the muscle mass. In the present study, we demonstrated as high as 60 and 52% downregulation (p < 0.01) of MSTN mRNA and protein in the primary fetal myoblast cells of goats using synthetic shRNAs (n = 3), without any interferon response. We, for the first time, evaluated the effect of MSTN knockdown on the expression of MRFs (namely, MyoD, Myf5), follistatin (FST), and IGFs (IGF-1 & IGF-2) in goat myoblast cells. MSTN knockdown caused an upregulation (p < 0.05) of MyoD and downregulation (p < 0.01) of MYf5 and FST expression. Moreover, we report up to ∼four fold (p < 0.001) enhanced proliferation in myoblasts after four days of culture. The anti-MSTN shRNA demonstrated in the present study could be used for the production of transgenic goats to increase the muscle mass.

Absence of muscle regeneration after implantation of a collagen matrix seeded with myoblasts

NARCIS (Netherlands)

van Wachem, PB; Brouwer, LA; van Luyn, MJA

Collagens are widely used as biomaterials for e.g. soft tissue reconstruction. The present study was aimed at reconstruction of abdominal wall muscle using processed dermal sheep collagen (DSC) and myoblast seeding. Myoblasts were harvested from foetal quadriceps muscle of an inbred rat strain,

Abelson tyrosine-protein kinase 2 regulates myoblast proliferation and controls muscle fiber length

Science.gov (United States)

Lee, Jennifer K; Hallock, Peter T

2017-01-01

Muscle fiber length is nearly uniform within a muscle but widely different among different muscles. We show that Abelson tyrosine-protein kinase 2 (Abl2) has a key role in regulating myofiber length, as a loss of Abl2 leads to excessively long myofibers in the diaphragm, intercostal and levator auris muscles but not limb muscles. Increased myofiber length is caused by enhanced myoblast proliferation, expanding the pool of myoblasts and leading to increased myoblast fusion. Abl2 acts in myoblasts, but as a consequence of expansion of the diaphragm muscle, the diaphragm central tendon is reduced in size, likely contributing to reduced stamina of Abl2 mutant mice. Ectopic muscle islands, each composed of myofibers of uniform length and orientation, form within the central tendon of Abl2+/− mice. Specialized tendon cells, resembling tendon cells at myotendinous junctions, form at the ends of these muscle islands, suggesting that myofibers induce differentiation of tendon cells, which reciprocally regulate myofiber length and orientation. PMID:29231808

Abelson tyrosine-protein kinase 2 regulates myoblast proliferation and controls muscle fiber length.

Science.gov (United States)

Lee, Jennifer K; Hallock, Peter T; Burden, Steven J

2017-12-12

Muscle fiber length is nearly uniform within a muscle but widely different among different muscles. We show that Abelson tyrosine-protein kinase 2 (Abl2) has a key role in regulating myofiber length, as a loss of Abl2 leads to excessively long myofibers in the diaphragm, intercostal and levator auris muscles but not limb muscles. Increased myofiber length is caused by enhanced myoblast proliferation, expanding the pool of myoblasts and leading to increased myoblast fusion. Abl2 acts in myoblasts, but as a consequence of expansion of the diaphragm muscle, the diaphragm central tendon is reduced in size, likely contributing to reduced stamina of Abl2 mutant mice. Ectopic muscle islands, each composed of myofibers of uniform length and orientation, form within the central tendon of Abl2 +/- mice. Specialized tendon cells, resembling tendon cells at myotendinous junctions, form at the ends of these muscle islands, suggesting that myofibers induce differentiation of tendon cells, which reciprocally regulate myofiber length and orientation.

Perspectives on stem cell therapy for cardiac regeneration. Advances and challenges.

Science.gov (United States)

Choi, Sung Hyun; Jung, Seok Yun; Kwon, Sang-Mo; Baek, Sang Hong

2012-01-01

Ischemic heart disease (IHD) accelerates cardiomyocyte loss, but the developing stem cell research could be useful for regenerating a variety of tissue cells, including cardiomyocytes. Diverse sources of stem cells for IHD have been reported, including embryonic stem cells, induced pluripotent stem cells, skeletal myoblasts, bone marrow-derived stem cells, mesenchymal stem cells, and cardiac stem cells. However, stem cells have unique advantages and disadvantages for cardiac tissue regeneration, which are important considerations in determining the specific cells for improving cell survival and long-term engraftment after transplantation. Additionally, the dosage and administration method of stem cells need to be standardized to increase stability and efficacy for clinical applications. Accordingly, this review presents a summary of the stem cell therapies that have been studied for cardiac regeneration thus far, and discusses the direction of future cardiac regeneration research for stem cells.

The small G-proteins Rac1 and Cdc42 are essential for myoblast fusion in the mouse

DEFF Research Database (Denmark)

Vasyutina, Elena; Martarelli, Benedetta; Brakebusch, Cord

2009-01-01

Rac1 and Cdc42 are small G-proteins that regulate actin dynamics and affect plasma membrane protrusion and vesicle traffic. We used conditional mutagenesis in mice to demonstrate that Rac1 and Cdc42 are essential for myoblast fusion in vivo and in vitro. The deficit in fusion of Rac1 or Cdc42 mut...... genetic analysis demonstrates thus that the function of Rac in myoblast fusion is evolutionarily conserved from insects to mammals and that Cdc42, a molecule hitherto not implicated in myoblast fusion, is essential for the fusion of murine myoblasts....

Marked heterogeneity in growth characteristics of myoblast clonal cultures and myoblast mixed cultures obtained from the same individual

NARCIS (Netherlands)

Maier, Andrea B.; Cohen, Ron; Blom, Joke; Van Heemst, Diana; Westendorp, Rudi G.J.

Background: Sarcopenia is defined as an age-related decrease in skeletal muscle mass and function while adjacent satellite cells are unable to compensate for this loss. However, myoblast cultures can be established even in the presence of sarcopenia. Objective: It is yet unknown whether satellite

Myostatin acts as an autocrine/paracrine negative regulator in myoblast differentiation from human induced pluripotent stem cells.

Science.gov (United States)

Gao, Fei; Kishida, Tsunao; Ejima, Akika; Gojo, Satoshi; Mazda, Osam

2013-02-08

Myostatin, also known as growth differentiation factor (GDF-8), regulates proliferation of muscle satellite cells, and suppresses differentiation of myoblasts into myotubes via down-regulation of key myogenic differentiation factors including MyoD. Recent advances in stem cell biology have enabled generation of myoblasts from pluripotent stem cells, but it remains to be clarified whether myostatin is also involved in regulation of artificial differentiation of myoblasts from pluripotent stem cells. Here we show that the human induced pluripotent stem (iPS) cell-derived cells that were induced to differentiate into myoblasts expressed myostatin and its receptor during the differentiation. An addition of recombinant human myostatin (rhMyostatin) suppressed induction of MyoD and Myo5a, resulting in significant suppression of myoblast differentiation. The rhMyostatin treatment also inhibited proliferation of the cells at a later phase of differentiation. RNAi-mediated silencing of myostatin promoted differentiation of human iPS-derived embryoid body (EB) cells into myoblasts. These results strongly suggest that myostatin plays an important role in regulation of myoblast differentiation from iPS cells of human origin. The present findings also have significant implications for potential regenerative medicine for muscular diseases. Copyright © 2013 Elsevier Inc. All rights reserved.

The MARVEL domain protein, Singles Bar, is required for progression past the pre-fusion complex stage of myoblast fusion.

Science.gov (United States)

Estrada, Beatriz; Maeland, Anne D; Gisselbrecht, Stephen S; Bloor, James W; Brown, Nicholas H; Michelson, Alan M

2007-07-15

Multinucleated myotubes develop by the sequential fusion of individual myoblasts. Using a convergence of genomic and classical genetic approaches, we have discovered a novel gene, singles bar (sing), that is essential for myoblast fusion. sing encodes a small multipass transmembrane protein containing a MARVEL domain, which is found in vertebrate proteins involved in processes such as tight junction formation and vesicle trafficking where--as in myoblast fusion--membrane apposition occurs. sing is expressed in both founder cells and fusion competent myoblasts preceding and during myoblast fusion. Examination of embryos injected with double-stranded sing RNA or embryos homozygous for ethane methyl sulfonate-induced sing alleles revealed an identical phenotype: replacement of multinucleated myofibers by groups of single, myosin-expressing myoblasts at a stage when formation of the mature muscle pattern is complete in wild-type embryos. Unfused sing mutant myoblasts form clusters, suggesting that early recognition and adhesion of these cells are unimpaired. To further investigate this phenotype, we undertook electron microscopic ultrastructural studies of fusing myoblasts in both sing and wild-type embryos. These experiments revealed that more sing mutant myoblasts than wild-type contain pre-fusion complexes, which are characterized by electron-dense vesicles paired on either side of the fusing plasma membranes. In contrast, embryos mutant for another muscle fusion gene, blown fuse (blow), have a normal number of such complexes. Together, these results lead to the hypothesis that sing acts at a step distinct from that of blow, and that sing is required on both founder cell and fusion-competent myoblast membranes to allow progression past the pre-fusion complex stage of myoblast fusion, possibly by mediating fusion of the electron-dense vesicles to the plasma membrane.

Spatial and functional restriction of regulatory molecules during mammalian myoblast fusion

International Nuclear Information System (INIS)

Pavlath, Grace K.

2010-01-01

Myoblast fusion is a highly regulated process that is key for forming skeletal muscle during development and regeneration in mammals. Much remains to be understood about the molecular regulation of myoblast fusion. Some molecules that influence mammalian muscle fusion display specific cellular localization during myogenesis. Such molecules can be localized to the contact region between two fusing cells either in both cells or only in one of the cells. How distinct localization of molecules contributes to fusion is not clear. Further complexity exists as other molecules are functionally restricted to myoblasts at later stages of myogenesis to regulate their fusion with multinucleated myotubes. This review examines these three categories of molecules and discusses how spatial and functional restriction may contribute to the formation of a multinucleated cell. Understanding how and why molecules become restricted in location or function is likely to provide further insights into the mechanisms regulating mammalian muscle fusion.

Novel lncRNAs in myogenesis: a miR-31 overlapping transcript controls myoblast differentiation.

KAUST Repository

Ballarino, Monica; Cazzella, Valentina; D'Andrea, Daniel; Grassi, Luigi; Bisceglie, Lavinia; Cipriano, Andrea; Santini, Tiziana; Pinnarò , Chiara; Morlando, Mariangela; Tramontano, Anna; Bozzoni, Irene

2014-01-01

Transcriptome analysis allowed the identification of new long noncoding RNAs differentially expressed during murine myoblast differentiation. These transcripts were classified on the basis of their expression under proliferating versus differentiated conditions, muscle-restricted activation, and subcellular localization. Several species displayed preferential expression in dystrophic (mdx) versus wild-type muscles, indicating their possible link with regenerative processes. One of the identified transcripts, lnc-31, even if originating from the same nuclear precursor of miR-31, is produced by a pathway mutually exclusive. We show that lnc-31 and its human homologue hsa-lnc-31 are expressed in proliferating myoblasts, where they counteract differentiation. In line with this, both species are more abundant in mdx muscles and in human Duchenne muscular dystrophy (DMD) myoblasts, than in their normal counterparts. Altogether, these data suggest a crucial role for lnc-31 in controlling the differentiation commitment of precursor myoblasts and indicate that its function is maintained in evolution despite the poor sequence conservation with the human counterpart.

Novel lncRNAs in myogenesis: a miR-31 overlapping transcript controls myoblast differentiation.

KAUST Repository

Ballarino, Monica

2014-12-15

Transcriptome analysis allowed the identification of new long noncoding RNAs differentially expressed during murine myoblast differentiation. These transcripts were classified on the basis of their expression under proliferating versus differentiated conditions, muscle-restricted activation, and subcellular localization. Several species displayed preferential expression in dystrophic (mdx) versus wild-type muscles, indicating their possible link with regenerative processes. One of the identified transcripts, lnc-31, even if originating from the same nuclear precursor of miR-31, is produced by a pathway mutually exclusive. We show that lnc-31 and its human homologue hsa-lnc-31 are expressed in proliferating myoblasts, where they counteract differentiation. In line with this, both species are more abundant in mdx muscles and in human Duchenne muscular dystrophy (DMD) myoblasts, than in their normal counterparts. Altogether, these data suggest a crucial role for lnc-31 in controlling the differentiation commitment of precursor myoblasts and indicate that its function is maintained in evolution despite the poor sequence conservation with the human counterpart.

TIPS to manipulate myogenesis: retention of myoblast differentiation capacity using microsphere culture

Directory of Open Access Journals (Sweden)

N Parmar

2015-07-01

Full Text Available Cell therapy is an emerging option for regenerating skeletal muscle. Improved delivery methods for anchorage-dependent myoblasts are likely to improve integration and function of transplanted muscle cells. Highly porous microspheres, produced using thermally induced phase separation (TIPS, have features ideally suited for minimally invasive cell delivery. The purpose of this study was to investigate, for the first time, the use of TIPS microspheres as highly porous microcarriers for manipulation of human skeletal muscle myoblasts (HSMM under defined culture conditions. HSMM cells readily attached to the surface of poly (DL-lactide-co-glycolide (PLGA TIPS microcarriers, where they were induced to continue proliferating or to be driven towards differentiation whilst under static-dynamic culture conditions for 7 days. Switching from proliferation medium to differentiation medium for 7 days, resulted in increased protein expression of skeletal muscle cell contractile apparatus components, MyoD and skeletal muscle myosin heavy chain, compared with cells cultured on conventional culture plasticware for the same duration (p < 0.001. Growth of myoblasts on the surface of the microcarriers and their migration following simulated delivery, caused no change to the proliferative capacity of cells over 7 days. Results from this study demonstrate that TIPS microspheres provide an ideal vehicle for the expansion and delivery of myoblasts for therapeutic applications. Transplantation of myoblasts anchored to a substrate, rather than in suspension, will reduce the amount of ex vivo manipulation required during preparation of the product and allows cells to be delivered in a more natural state. This will improve the ability to control cell dosage and increase the likelihood of efficacy.

Function of skeletal muscle tissue formed after myoblast transplantation into irradiated mouse muscles.

Science.gov (United States)

Wernig, A; Zweyer, M; Irintchev, A

2000-01-15

1. Pretreatment of muscles with ionising radiation enhances tissue formation by transplanted myoblasts but little is known about the effects on muscle function. We implanted myoblasts from an expanded, male-donor-derived, culture (i28) into X-ray irradiated (16 Gy) or irradiated and damaged soleus muscles of female syngeneic mice (Balb/c). Three to 6 months later the isometric contractile properties of the muscles were studied in vitro, and donor nuclei were visualised in muscle sections with a Y chromosome-specific DNA probe. 2. Irradiated sham-injected muscles had smaller masses than untreated solei and produced less twitch and tetanic force (all by about 18 %). Injection of 106 myoblasts abolished these deficiencies and innervation appeared normal. 3. Cryodamage of irradiated solei produced muscle remnants with few (1-50) or no fibres. Additional myoblast implantation led to formation of large muscles (25 % above normal) containing numerous small-diameter fibres. Upon direct electrical stimulation, these muscles produced considerable twitch (53 % of normal) and tetanic forces (35 % of normal) but innervation was insufficient as indicated by weak nerve-evoked contractions and elevated ACh sensitivity. 4. In control experiments on irradiated muscles, reinnervation was found to be less complete after botulinum toxin paralysis than after nerve crush indicating that proliferative arrest of irradiated Schwann cells may account for the observed innervation deficits. 5. Irradiation appears to be an effective pretreatment for improving myoblast transplantation. The injected cells can even produce organised contractile tissue replacing whole muscle. However, impaired nerve regeneration limits the functional performance of the new muscle.

Transdifferentiation of myoblasts into osteoblasts - possible use for bone therapy.

Science.gov (United States)

Lin, Daphne P L; Carnagarin, Revathy; Dharmarajan, Arun; Dass, Crispin R

2017-12-01

Transdifferentiation is defined as the conversion of one cell type to another and is an ever-expanding field with a growing number of cells found to be capable of such a process. To date, the fact remains that there are limited treatment options for fracture healing, osteoporosis and bone repair post-destruction by bone tumours. Hence, this review focuses on the transdifferentiation of myoblast to osteoblast as a means to further understand the transdifferentiation process and to investigate a potential therapeutic option if successful. The potent osteoinductive effects of the bone morphogenetic protein-2 are largely implicated in the transdifferentiation of myoblast to osteoblast. Bone morphogenetic protein-2-induced activation of the Smad1 protein ultimately results in JunB synthesis, the first transcriptional step in myoblast dedifferentiation. The upregulation of the activating protein-1 binding activity triggers the transcription of the runt-related transcription factor 2 gene, a transcription factor that plays a major role in osteoblast differentiation. This potential transdifferentiation treatment may be utilised for dental implants, fracture healing, osteoporosis and bone repair post-destruction by bone tumours. © 2017 Royal Pharmaceutical Society.

CD36 is required for myoblast fusion during myogenic differentiation

International Nuclear Information System (INIS)

Park, Seung-Yoon; Yun, Youngeun; Kim, In-San

2012-01-01

Highlights: ► CD36 expression was induced during myogenic differentiation. ► CD36 expression was localized in multinucleated myotubes. ► The expression of myogenic markers is attenuated in CD36 knockdown C2C12 cells. ► Knockdown of CD36 significantly inhibited myotube formation during differentiation. -- Abstract: Recently, CD36 has been found to be involved in the cytokine-induced fusion of macrophage. Myoblast fusion to form multinucleated myotubes is required for myogenesis and muscle regeneration. Because a search of gene expression database revealed the attenuation of CD36 expression in the muscles of muscular dystrophy patients, the possibility that CD36 could be required for myoblast fusion was investigated. CD36 expression was markedly up-regulated during myoblast differentiation and localized in multinucleated myotubes. Knockdown of endogenous CD36 significantly decreased the expression of myogenic markers as well as myotube formation. These results support the notion that CD36 plays an important role in cell fusion during myogenic differentiation. Our finding will aid the elucidation of the common mechanism governing cell-to-cell fusion in various fusion models.

CD36 is required for myoblast fusion during myogenic differentiation

Energy Technology Data Exchange (ETDEWEB)

Park, Seung-Yoon [Department of Biochemistry, College of Medicine, Dongguk University and Medical Institute of Dongguk University, Gyeongju 780-714 (Korea, Republic of); Yun, Youngeun [Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Kim, In-San, E-mail: iskim@knu.ac.kr [Department of Biochemistry and Cell Biology, Cell and Matrix Research Institute, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Biomedical Research Institute, Korea Institute Science and Technology, Seoul (Korea, Republic of)

2012-11-02

Highlights: Black-Right-Pointing-Pointer CD36 expression was induced during myogenic differentiation. Black-Right-Pointing-Pointer CD36 expression was localized in multinucleated myotubes. Black-Right-Pointing-Pointer The expression of myogenic markers is attenuated in CD36 knockdown C2C12 cells. Black-Right-Pointing-Pointer Knockdown of CD36 significantly inhibited myotube formation during differentiation. -- Abstract: Recently, CD36 has been found to be involved in the cytokine-induced fusion of macrophage. Myoblast fusion to form multinucleated myotubes is required for myogenesis and muscle regeneration. Because a search of gene expression database revealed the attenuation of CD36 expression in the muscles of muscular dystrophy patients, the possibility that CD36 could be required for myoblast fusion was investigated. CD36 expression was markedly up-regulated during myoblast differentiation and localized in multinucleated myotubes. Knockdown of endogenous CD36 significantly decreased the expression of myogenic markers as well as myotube formation. These results support the notion that CD36 plays an important role in cell fusion during myogenic differentiation. Our finding will aid the elucidation of the common mechanism governing cell-to-cell fusion in various fusion models.

Ductile electroactive biodegradable hyperbranched polylactide copolymers enhancing myoblast differentiation.

Science.gov (United States)

Xie, Meihua; Wang, Ling; Guo, Baolin; Wang, Zhong; Chen, Y Eugene; Ma, Peter X

2015-12-01

Myotube formation is crucial to restoring muscular functions, and biomaterials that enhance the myoblast differentiation into myotubes are highly desirable for muscular repair. Here, we report the synthesis of electroactive, ductile, and degradable copolymers and their application in enhancing the differentiation of myoblasts to myotubes. A hyperbranched ductile polylactide (HPLA) was synthesized and then copolymerized with aniline tetramer (AT) to produce a series of electroactive, ductile and degradable copolymers (HPLAAT). The HPLA and HPLAAT showed excellent ductility with strain to failure from 158.9% to 42.7% and modulus from 265.2 to 758.2 MPa. The high electroactivity of the HPLAAT was confirmed by UV spectrometer and cyclic voltammogram measurements. These HPLAAT polymers also showed improved thermal stability and controlled biodegradation rate compared to HPLA. Importantly, when applying these polymers for myotube formation, the HPLAAT significantly improved the proliferation of C2C12 myoblasts in vitro compared to HPLA. Furthermore, these polymers greatly promoted myogenic differentiation of C2C12 cells as measured by quantitative analysis of myotube number, length, diameter, maturation index, and gene expression of MyoD and TNNT. Together, our study shows that these electroactive, ductile and degradable HPLAAT copolymers represent significantly improved biomaterials for muscle tissue engineering compared to HPLA. Copyright © 2015 Elsevier Ltd. All rights reserved.

Estrogens enhance myoblast differentiation in facioscapulohumeral muscular dystrophy by antagonizing DUX4 activity

OpenAIRE

Teveroni, Emanuela; Pellegrino, Marsha; Sacconi, Sabrina; Calandra, Patrizia; Cascino, Isabella; Farioli-Vecchioli, Stefano; Puma, Angela; Garibaldi, Matteo; Morosetti, Roberta; Tasca, Giorgio; Ricci, Enzo; Trevisan, Carlo Pietro; Galluzzi, Giuliana; Pontecorvi, Alfredo; Crescenzi, Marco

2017-01-01

Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant neuromuscular disorder that is characterized by extreme variability in symptoms, with females being less severely affected than males and presenting a higher proportion of asymptomatic carriers. The sex-related factors involved in the disease are not known. Here, we have utilized myoblasts isolated from FSHD patients (FSHD myoblasts) to investigate the effect of estrogens on muscle properties. Our results demonstrated that...

Myoblast transplantation for heart repair: A review of the state of the field

Institute of Scientific and Technical Information of China (English)

Howard J. Leonhardt; Michael Brown

2006-01-01

Over 200 humans have been treated with myoblast transplantation for heart muscle repair since June 2000. Bioheart sponsored percutaneous delivery studies began in May 2001 in Europe. Approximately one third of the patients have exhibited substantial improvement in left ventricular ejection fraction (LVEF) of over 30% and two heart failure class improvements. Over 80% of the patients have exhibited one heart failure class improvement with moderate improvement of LVEF. Clinical trials seem to demonstrate a marked reduction in emergency hospitalizations in myoblast treated patients. Many years of careful studies have lead to randomized controlled studies that are enrolling patients now at numerous centers worldwide. A firm conclusion on the safety and efficacy of myoblast transplantation cannot be determined until these randomized studies are completed. Final results from randomized controlled studies should be available soon. (J Geriatr Cardiol 2006;3:165-7.)

Laminin-Coated Poly(Methyl Methacrylate) (PMMA) Nanofiber Scaffold Facilitates the Enrichment of Skeletal Muscle Myoblast Population.

Science.gov (United States)

Zahari, Nor Kamalia; Idrus, Ruszymah Binti Haji; Chowdhury, Shiplu Roy

2017-10-30

Myoblasts, the contractile cells of skeletal muscle, have been invaluable for fundamental studies of muscle development and clinical applications for muscle loss. A major limitation to the myoblast-based therapeutic approach is contamination with non-contractile fibroblasts, which overgrow during cell expansion. To overcome these limitations, this study was carried out to establish a 3D culture environment using nanofiber scaffolds to enrich the myoblast population during construct formation. Poly(methyl methacrylate) (PMMA) nanofiber (PM) scaffolds were fabricated using electrospinning techniques and coated with extracellular matrix (ECM) proteins, such as collagen or laminin, in the presence or absence of genipin. A mixed population of myoblasts and fibroblasts was isolated from human skeletal muscle tissues and cultured on plain surfaces, as well as coated and non-coated PM scaffolds. PMMA can produce smooth fibers with an average diameter of 360 ± 50 nm. Adsorption of collagen and laminin on PM scaffolds is significantly enhanced in the presence of genipin, which introduces roughness to the nanofiber surface without affecting fiber diameter and mechanical properties. It was also demonstrated that laminin-coated PM scaffolds significantly enhance myoblast proliferation (0.0081 ± 0.0007 h -1 ) and migration (0.26 ± 0.04 μm/min), while collagen-coated PM scaffolds favors fibroblasts proliferation (0.0097 ± 0.0009 h -1 ) and migration (0.23 ± 0.03 μm/min). Consequently, the myoblast population was enriched on laminin-coated PM scaffolds throughout the culture process. Therefore, laminin coating of nanofiber scaffolds could be a potential scaffold for the development of a tissue-engineered muscle substitute.

Bone Marrow Mesenchymal Stromal Cells Stimulate Skeletal Myoblast Proliferation through the Paracrine Release of VEGF

Science.gov (United States)

Chellini, Flaminia; Mazzanti, Benedetta; Nistri, Silvia; Nosi, Daniele; Saccardi, Riccardo; Quercioli, Franco; Zecchi-Orlandini, Sandra; Formigli, Lucia

2012-01-01

Mesenchymal stromal cells (MSCs) are the leading cell candidates in the field of regenerative medicine. These cells have also been successfully used to improve skeletal muscle repair/regeneration; however, the mechanisms responsible for their beneficial effects remain to be clarified. On this basis, in the present study, we evaluated in a co-culture system, the ability of bone-marrow MSCs to influence C2C12 myoblast behavior and analyzed the cross-talk between the two cell types at the cellular and molecular level. We found that myoblast proliferation was greatly enhanced in the co-culture as judged by time lapse videomicroscopy, cyclin A expression and EdU incorporation. Moreover, myoblasts immunomagnetically separated from MSCs after co-culture expressed higher mRNA and protein levels of Notch-1, a key determinant of myoblast activation and proliferation, as compared with the single culture. Notch-1 intracellular domain and nuclear localization of Hes-1, a Notch-1 target gene, were also increased in the co-culture. Interestingly, the myoblastic response was mainly dependent on the paracrine release of vascular endothelial growth factor (VEGF) by MSCs. Indeed, the addition of MSC-derived conditioned medium (CM) to C2C12 cells yielded similar results as those observed in the co-culture and increased the phosphorylation and expression levels of VEGFR. The treatment with the selective pharmacological VEGFR inhibitor, KRN633, resulted in a marked attenuation of the receptor activation and concomitantly inhibited the effects of MSC-CM on C2C12 cell growth and Notch-1 signaling. In conclusion, this study provides novel evidence for a role of MSCs in stimulating myoblast cell proliferation and suggests that the functional interaction between the two cell types may be exploited for the development of new and more efficient cell-based skeletal muscle repair strategies. PMID:22815682

Phosphoinositide 3-kinase/Akt signalling is responsible for the differential susceptibility of myoblasts and myotubes to menadione-induced oxidative stress.

Science.gov (United States)

Lim, Jeong A; Woo, Joo Hong; Kim, Hye Sun

2008-09-01

In this study, it was found that undifferentiated myoblasts were more vulnerable to menadione-induced oxidative stress than differentiated myotubes. Cell death occurred with a relatively low concentration of menadione in myoblasts compared to myotubes. With the same concentration of menadione, the Bcl-2/Bax ratio decreased and nuclei containing condensed chromatin were observed in myoblasts to a greater extent than in myotubes. However, myotubes became increasingly susceptible to menadione when phosphoinositide 3-kinase (PI3-K) was blocked by pre-incubation with LY294002, a PI3-K inhibitor. Actually, PI3-K activity was reduced by menadione in myoblasts but not in myotubes. In addition, the phosphorylation of Akt, a downstream effector of PI3-K, was inhibited in myoblasts by menadione but increased in myotubes. Both LY294002 and API-2, an Akt inhibitor, decreased the Bcl-2/Bax ratio in menadione-exposed myotubes. These results suggest that the differential activity of PI3-K/Akt signalling is responsible for the differential susceptibility of myoblasts and myotubes to menadione-induced oxidative stress.

An integrated strategy for analyzing the unique developmental programs of different myoblast subtypes.

Directory of Open Access Journals (Sweden)

2006-02-01

Full Text Available An important but largely unmet challenge in understanding the mechanisms that govern the formation of specific organs is to decipher the complex and dynamic genetic programs exhibited by the diversity of cell types within the tissue of interest. Here, we use an integrated genetic, genomic, and computational strategy to comprehensively determine the molecular identities of distinct myoblast subpopulations within the Drosophila embryonic mesoderm at the time that cell fates are initially specified. A compendium of gene expression profiles was generated for primary mesodermal cells purified by flow cytometry from appropriately staged wild-type embryos and from 12 genotypes in which myogenesis was selectively and predictably perturbed. A statistical meta-analysis of these pooled datasets--based on expected trends in gene expression and on the relative contribution of each genotype to the detection of known muscle genes--provisionally assigned hundreds of differentially expressed genes to particular myoblast subtypes. Whole embryo in situ hybridizations were then used to validate the majority of these predictions, thereby enabling true-positive detection rates to be estimated for the microarray data. This combined analysis reveals that myoblasts exhibit much greater gene expression heterogeneity and overall complexity than was previously appreciated. Moreover, it implicates the involvement of large numbers of uncharacterized, differentially expressed genes in myogenic specification and subsequent morphogenesis. These findings also underscore a requirement for considerable regulatory specificity for generating diverse myoblast identities. Finally, to illustrate how the developmental functions of newly identified myoblast genes can be efficiently surveyed, a rapid RNA interference assay that can be scored in living embryos was developed and applied to selected genes. This integrated strategy for examining embryonic gene expression and function provides

Laminin-Coated Poly(Methyl Methacrylate (PMMA Nanofiber Scaffold Facilitates the Enrichment of Skeletal Muscle Myoblast Population

Directory of Open Access Journals (Sweden)

Nor Kamalia Zahari

2017-10-01

Full Text Available Myoblasts, the contractile cells of skeletal muscle, have been invaluable for fundamental studies of muscle development and clinical applications for muscle loss. A major limitation to the myoblast-based therapeutic approach is contamination with non-contractile fibroblasts, which overgrow during cell expansion. To overcome these limitations, this study was carried out to establish a 3D culture environment using nanofiber scaffolds to enrich the myoblast population during construct formation. Poly(methyl methacrylate (PMMA nanofiber (PM scaffolds were fabricated using electrospinning techniques and coated with extracellular matrix (ECM proteins, such as collagen or laminin, in the presence or absence of genipin. A mixed population of myoblasts and fibroblasts was isolated from human skeletal muscle tissues and cultured on plain surfaces, as well as coated and non-coated PM scaffolds. PMMA can produce smooth fibers with an average diameter of 360 ± 50 nm. Adsorption of collagen and laminin on PM scaffolds is significantly enhanced in the presence of genipin, which introduces roughness to the nanofiber surface without affecting fiber diameter and mechanical properties. It was also demonstrated that laminin-coated PM scaffolds significantly enhance myoblast proliferation (0.0081 ± 0.0007 h−1 and migration (0.26 ± 0.04 μm/min, while collagen-coated PM scaffolds favors fibroblasts proliferation (0.0097 ± 0.0009 h−1 and migration (0.23 ± 0.03 μm/min. Consequently, the myoblast population was enriched on laminin-coated PM scaffolds throughout the culture process. Therefore, laminin coating of nanofiber scaffolds could be a potential scaffold for the development of a tissue-engineered muscle substitute.

Biomarker-free dielectrophoretic sorting of differentiating myoblast multipotent progenitor cells and their membrane analysis by Raman spectroscopy.

Science.gov (United States)

Muratore, Massimo; Srsen, Vlastimil; Waterfall, Martin; Downes, Andrew; Pethig, Ronald

2012-09-01

Myoblasts are muscle derived mesenchymal stem cell progenitors that have great potential for use in regenerative medicine, especially for cardiomyogenesis grafts and intracardiac cell transplantation. To utilise such cells for pre-clinical and clinical applications, and especially for personalized medicine, it is essential to generate a synchronised, homogenous, population of cells that display phenotypic and genotypic homogeneity within a population of cells. We demonstrate that the biomarker-free technique of dielectrophoresis (DEP) can be used to discriminate cells between stages of differentiation in the C2C12 myoblast multipotent mouse model. Terminally differentiated myotubes were separated from C2C12 myoblasts to better than 96% purity, a result validated by flow cytometry and Western blotting. To determine the extent to which cell membrane capacitance, rather than cell size, determined the DEP response of a cell, C2C12 myoblasts were co-cultured with GFP-expressing MRC-5 fibroblasts of comparable size distributions (mean diameter ∼10 μm). A DEP sorting efficiency greater than 98% was achieved for these two cell types, a result concluded to arise from the fibroblasts possessing a larger membrane capacitance than the myoblasts. It is currently assumed that differences in membrane capacitance primarily reflect differences in the extent of folding or surface features of the membrane. However, our finding by Raman spectroscopy that the fibroblast membranes contained a smaller proportion of saturated lipids than those of the myoblasts suggests that the membrane chemistry should also be taken into account.

DRAGON, a GPI-anchored membrane protein, inhibits BMP signaling in C2C12 myoblasts.

Science.gov (United States)

Kanomata, Kazuhiro; Kokabu, Shoichiro; Nojima, Junya; Fukuda, Toru; Katagiri, Takenobu

2009-06-01

Bone morphogenetic proteins (BMPs) induce osteoblastic differentiation of myoblasts via binding to cell surface receptors. Repulsive guidance molecules (RGMs) have been identified as BMP co-receptors. We report here that DRAGON/RGMb, a member of the RGM family, suppressed BMP signaling in C2C12 myoblasts via a novel mechanism. All RGMs were expressed in C2C12 cells that were differentiated into myocytes and osteoblastic cells, but RGMc was not detected in immature cells. In C2C12 cells, only DRAGON suppressed ALP and Id1 promoter activities induced by BMP-4 or by constitutively activated BMP type I receptors. This inhibition by DRAGON was dependent on the secretory form of the von Willbrand factor type D domain. DRAGON even suppressed BMP signaling induced by constitutively activated Smad1. Over-expression of neogenin did not alter the inhibitory capacity of DRAGON. Taken together, these findings indicate that DRAGON may be an inhibitor of BMP signaling in C2C12 myoblasts. We also suggest that a novel molecule(s) expressed on the cell membrane may mediate the signal transduction of DRAGON in order to suppress BMP signaling in C2C12 myoblasts.

The Tocotrienol-Rich Fraction Is Superior to Tocopherol in Promoting Myogenic Differentiation in the Prevention of Replicative Senescence of Myoblasts.

Directory of Open Access Journals (Sweden)

Shy Cian Khor

Full Text Available Aging results in a loss of muscle mass and strength. Myoblasts play an important role in maintaining muscle mass through regenerative processes, which are impaired during aging. Vitamin E potentially ameliorates age-related phenotypes. Hence, this study aimed to determine the effects of the tocotrienol-rich fraction (TRF and α-tocopherol (ATF in protecting myoblasts from replicative senescence and promoting myogenic differentiation. Primary human myoblasts were cultured into young and senescent stages and were then treated with TRF or ATF for 24 h, followed by an analysis of cell proliferation, senescence biomarkers, cellular morphology and differentiation. Our data showed that replicative senescence impaired the normal regenerative processes of myoblasts, resulting in changes in cellular morphology, cell proliferation, senescence-associated β-galactosidase (SA-β-gal expression, myogenic differentiation and myogenic regulatory factors (MRFs expression. Treatment with both TRF and ATF was beneficial to senescent myoblasts in reclaiming the morphology of young cells, improved cell viability and decreased SA-β-gal expression. However, only TRF treatment increased BrdU incorporation in senescent myoblasts, as well as promoted myogenic differentiation through the modulation of MRFs at the mRNA and protein levels. MYOD1 and MYOG gene expression and myogenin protein expression were modulated in the early phases of myogenic differentiation. In conclusion, the tocotrienol-rich fraction is superior to α-tocopherol in ameliorating replicative senescence-related aberration and promoting differentiation via modulation of MRFs expression, indicating vitamin E potential in modulating replicative senescence of myoblasts.

Hypomorphic Smn knockdown C2C12 myoblasts reveal intrinsic defects in myoblast fusion and myotube morphology

International Nuclear Information System (INIS)

Shafey, Dina; Cote, Patrice D.; Kothary, Rashmi

2005-01-01

Dosage of the survival motor neuron (SMN) protein has been directly correlated with the severity of disease in patients diagnosed with spinal muscular atrophy (SMA). It is also clear that SMA is a neurodegenerative disorder characterized by the degeneration of the α-motor neurons in the anterior horn of the spinal cord and atrophy of the associated skeletal muscle. What is more controversial is whether it is neuronal and/or muscle-cell-autonomous defects that are responsible for the disease per se. Although motor neuron degeneration is generally accepted as the primary event in SMA, intrinsic muscle defects in this disease have not been ruled out. To gain a better understanding of the influence of SMN protein dosage in muscle, we have generated a hypomorphic series of myoblast (C2C12) stable cell lines with variable Smn knockdown. We show that depletion of Smn in these cells resulted in a decrease in the number of nuclear 'gems' (gemini of coiled bodies), reduced proliferation with no increase in cell death, defects in myoblast fusion, and malformed myotubes. Importantly, the severity of these abnormalities is directly correlated with the decrease in Smn dosage. Taken together, our work supports the view that there is an intrinsic defect in skeletal muscle cells of SMA patients and that this defect contributes to the overall pathogenesis in this devastating disease

Skeletal Myoblast Cell Sheet Implantation Ameliorates Both Systolic and Diastolic Cardiac Performance in Canine Dilated Cardiomyopathy Model.

Science.gov (United States)

Shirasaka, Tomonori; Miyagawa, Shigeru; Fukushima, Satsuki; Kawaguchi, Naomasa; Nakatani, Satoshi; Daimon, Takashi; Okita, Yutaka; Sawa, Yoshiki

2016-02-01

Improving both systolic and diastolic function may be the most important factor in treating heart failure. In this study, we hypothesized that cell-sheet transplantation could improve these function in the damaged heart. We generated a dilated cardiomyopathy model in beagles by continuous ventricle pacing at 240 beats per minute. After 4 weeks, the beagles underwent skeletal myoblast cell sheet transplantation (SMCST) or a sham operation, and rapid ventricle pacing continued for an additional 4 weeks. Six of the e8 beagles treated by SMCST were still alive 4 weeks after the procedure. We evaluated SMCST's cardiotherapeutic effects by comparing beagles treated by SMCST with beagles that underwent a sham operation (control, n = 5). Diastolic function, as well as systolic function improved significantly in the SMCST group as compared with the sham group (control vs SMCST group, median [interquartile range]: E/E', 16 [0.9] vs 11 [1.0]; P dilated cardiomyopathy heart.

Developmental Programming in Response to Intrauterine Growth Restriction Impairs Myoblast Function and Skeletal Muscle Metabolism

Science.gov (United States)

Yates, D. T.; Macko, A. R.; Nearing, M.; Chen, X.; Rhoads, R. P.; Limesand, S. W.

2012-01-01

Fetal adaptations to placental insufficiency alter postnatal metabolic homeostasis in skeletal muscle by reducing glucose oxidation rates, impairing insulin action, and lowering the proportion of oxidative fibers. In animal models of intrauterine growth restriction (IUGR), skeletal muscle fibers have less myonuclei at birth. This means that myoblasts, the sole source for myonuclei accumulation in fibers, are compromised. Fetal hypoglycemia and hypoxemia are complications that result from placental insufficiency. Hypoxemia elevates circulating catecholamines, and chronic hypercatecholaminemia has been shown to reduce fetal muscle development and growth. We have found evidence for adaptations in adrenergic receptor expression profiles in myoblasts and skeletal muscle of IUGR sheep fetuses with placental insufficiency. The relationship of β-adrenergic receptors shifts in IUGR fetuses because Adrβ2 expression levels decline and Adrβ1 expression levels are unaffected in myofibers and increased in myoblasts. This adaptive response would suppress insulin signaling, myoblast incorporation, fiber hypertrophy, and glucose oxidation. Furthermore, this β-adrenergic receptor expression profile persists for at least the first month in IUGR lambs and lowers their fatty acid mobilization. Developmental programming of skeletal muscle adrenergic receptors partially explains metabolic and endocrine differences in IUGR offspring, and the impact on metabolism may result in differential nutrient utilization. PMID:22900186

Biodistribution studies of 99mTc-labeled myoblasts in a murine model of muscular dystrophy

International Nuclear Information System (INIS)

Colombo, F.R.; Torrente, Y.; Casati, R.; Benti, R.; Corti, S.; Salani, S.; D'Angelo, M.G.; DeLiso, A.; Scarlato, G.; Bresolin, N.; Gerundini, P.

2001-01-01

The purpose of this study was twofold: first, to evaluate the myoblast labeling of various 99m Tc complexes and to select the complex that best accomplishes this labeling, and second to evaluate the biodistribution of myoblasts labeled with this complex using mice with MDX muscular dystrophy (the murine homologue of Duchenne's muscular dystrophy). The following ligands were used to prepare the corresponding 99m Tc complexes: hexakis-methoxy-isobutyl-isonitrile (MIBI), bis(2-ethoxyethyl)diphosphinoethane (Tf), (RR,SS)-4,8-diaza-3,6,6,9-tetramethyl-undecane-2,10-dione-bisoxime (HM-PAO), bis(N-ethyl)dithiocarbamate (NEt), and bis(N-ethoxy, N-ethyl)dithiocarbamate (NOEt). One million murine myoblasts were incubated for 30-60 minutes with 5 mCi of each of the 99mTc complexes prepared from the above ligands. Viability was assessed by microscopic counting after trypan blue staining, and the radioactivity absorbed in the cells was measured after centrifugation. The compound with the highest uptake in cellular pellets was [ 99m Tc]N-NOEt. The biodistribution of myoblasts labeled with this complex was evaluated after intraaortic injection in dystrophic mice. Such an approach has the potential of effecting widespread gene transfer through the bloodstream to muscles lacking dystrophin

Developmental Programming in Response to Intrauterine Growth Restriction Impairs Myoblast Function and Skeletal Muscle Metabolism

Directory of Open Access Journals (Sweden)

D. T. Yates

2012-01-01

Full Text Available Fetal adaptations to placental insufficiency alter postnatal metabolic homeostasis in skeletal muscle by reducing glucose oxidation rates, impairing insulin action, and lowering the proportion of oxidative fibers. In animal models of intrauterine growth restriction (IUGR, skeletal muscle fibers have less myonuclei at birth. This means that myoblasts, the sole source for myonuclei accumulation in fibers, are compromised. Fetal hypoglycemia and hypoxemia are complications that result from placental insufficiency. Hypoxemia elevates circulating catecholamines, and chronic hypercatecholaminemia has been shown to reduce fetal muscle development and growth. We have found evidence for adaptations in adrenergic receptor expression profiles in myoblasts and skeletal muscle of IUGR sheep fetuses with placental insufficiency. The relationship of β-adrenergic receptors shifts in IUGR fetuses because Adrβ2 expression levels decline and Adrβ1 expression levels are unaffected in myofibers and increased in myoblasts. This adaptive response would suppress insulin signaling, myoblast incorporation, fiber hypertrophy, and glucose oxidation. Furthermore, this β-adrenergic receptor expression profile persists for at least the first month in IUGR lambs and lowers their fatty acid mobilization. Developmental programming of skeletal muscle adrenergic receptors partially explains metabolic and endocrine differences in IUGR offspring, and the impact on metabolism may result in differential nutrient utilization.

Proliferation of Human Primary Myoblasts Is Associated with Altered Energy Metabolism in Dependence on Ageing In Vivo and In Vitro

Directory of Open Access Journals (Sweden)

Reedik Pääsuke

2016-01-01

Full Text Available Background. Ageing is associated with suppressed regenerative potential of muscle precursor cells due to decrease of satellite cells and suppressive intramuscular milieu on their activation, associated with ageing-related low-grade inflammation. The aim of the study was to characterize the function of oxidative phosphorylation (OXPHOS, glycolysis, adenylate kinase (AK, and creatine kinase (CK mediated systems in young and older individuals. Materials and Methods. Myoblasts were cultivated from biopsies taken by transcutaneous conchotomy from vastus lateralis muscle in young (20–29 yrs, n=7 and older (70–79 yrs, n=7 subjects. Energy metabolism was assessed in passages 2 to 6 by oxygraphy and enzyme analysis. Results. In myoblasts of young and older subjects the rate of OXPHOS decreased during proliferation from passages 2 to 6. The total activities of CK and AK decreased. Myoblasts of passage 2 cultivated from young muscle showed higher rate of OXPHOS and activities of CK and AK compared to myoblasts from older subjects while hexokinase and pyruvate kinase were not affected by ageing. Conclusions. Proliferation of myoblasts in vitro is associated with downregulation of OXPHOS and energy storage and transfer systems. Ageing in vivo exerts an impact on satellite cells which results in altered metabolic profile in favour of the prevalence of glycolytic pathways over mitochondrial OXPHOS of myoblasts.

Inhibition of Na+ channel currents in rat myoblasts by 4-aminopyridine

International Nuclear Information System (INIS)

Lu Boxun; Liu Linyun; Liao Lei; Zhang Zhihong; Mei Yanai

2005-01-01

Our previous study revealed that 4-aminopyridine (4-AP), a specific blocker of A-type current, could also inhibit inward Na + currents (I Na ) with a state-independent mechanism in rat cerebellar granule cells. In the present study, we report an inhibitory effect of 4-AP on voltage-gated and tetrodotoxin (TTX)-sensitive I Na recorded from cultured rat myoblasts. 4-AP inhibited I Na amplitude in a dose-dependent manner between the concentrations of 0.5 and 10 mM without significant alteration in the activation or inactivation kinetics of the channel. By comparison to the 4-AP-induced inhibitory effect on cerebellum neurons, the inhibitory effect on myoblasts was enhanced through repetitive pulse and inflected by changing frequency. Specifically, the lower the frequency of pulse, the higher the inhibition observed, suggesting that block manner is inversely use-dependent. Moreover, experiments adding 4-AP to the intracellular solution indicate that the inhibitory effects are localized inside the cell. Additionally, 4-AP significantly modifies the properties of steady-state activation and inactivation kinetics of the channel. Our data suggest that the K + channel blocker 4-AP inhibits both neuron and myoblast Na + channels via different mechanisms. These findings may also provide information regarding 4-AP-induced pharmacological and toxicological effects in clinical use and experimental research

Cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser.

Science.gov (United States)

Alexsandra da Silva Neto Trajano, Larissa; da Silva, Camila Luna; de Carvalho, Simone Nunes; Cortez, Erika; Mencalha, André Luiz; de Souza da Fonseca, Adenilson; Stumbo, Ana Carolina

2016-07-01

Low-level infrared laser is considered safe and effective for treatment of muscle injuries. However, the mechanism involved on beneficial effects of laser therapy are not understood. The aim was to evaluate cell viability, reactive oxygen species, apoptosis, and necrosis in myoblast cultures exposed to low-level infrared laser at therapeutic fluences. C2C12 myoblast cultures at different (2 and 10 %) fetal bovine serum (FBS) concentrations were exposed to low-level infrared laser (808 nm, 100 mW) at different fluences (10, 35, and 70 J/cm(2)) and evaluated after 24, 48, and 72 h. Cell viability was evaluated by WST-1 assay; reactive oxygen species (ROS), apoptosis, and necrosis were evaluated by flow cytometry. Cell viability was decreased atthe lowest FBS concentration. Laser exposure increased the cell viability in myoblast cultures at 2 % FBS after 48 and 72 h, but no significant increase in ROS was observed. Apoptosis was decreased at the higher fluence and necrosis was increased at lower fluence in myoblast cultures after 24 h of laser exposure at 2 % FBS. No laser-induced alterations were obtained at 10 % FBS. Results show that level of reactive oxygen species is not altered, at least to those evaluated in this study, but low-level infrared laser exposure affects cell viability, apoptosis, and necrosis in myoblast cultures depending on laser fluence and physiologic conditions of cells.

Biodistribution studies of {sup 99m}Tc-labeled myoblasts in a murine model of muscular dystrophy

Energy Technology Data Exchange (ETDEWEB)

Colombo, F.R. E-mail: colombof@policlinico.mi.it; Torrente, Y.; Casati, R.; Benti, R.; Corti, S.; Salani, S.; D' Angelo, M.G.; DeLiso, A.; Scarlato, G.; Bresolin, N.; Gerundini, P

2001-11-01

The purpose of this study was twofold: first, to evaluate the myoblast labeling of various {sup 99m}Tc complexes and to select the complex that best accomplishes this labeling, and second to evaluate the biodistribution of myoblasts labeled with this complex using mice with MDX muscular dystrophy (the murine homologue of Duchenne's muscular dystrophy). The following ligands were used to prepare the corresponding {sup 99m}Tc complexes: hexakis-methoxy-isobutyl-isonitrile (MIBI), bis(2-ethoxyethyl)diphosphinoethane (Tf), (RR,SS)-4,8-diaza-3,6,6,9-tetramethyl-undecane-2,10-dione-bisoxime (HM-PAO), bis(N-ethyl)dithiocarbamate (NEt), and bis(N-ethoxy, N-ethyl)dithiocarbamate (NOEt). One million murine myoblasts were incubated for 30-60 minutes with 5 mCi of each of the 99mTc complexes prepared from the above ligands. Viability was assessed by microscopic counting after trypan blue staining, and the radioactivity absorbed in the cells was measured after centrifugation. The compound with the highest uptake in cellular pellets was [{sup 99m}Tc]N-NOEt. The biodistribution of myoblasts labeled with this complex was evaluated after intraaortic injection in dystrophic mice. Such an approach has the potential of effecting widespread gene transfer through the bloodstream to muscles lacking dystrophin.

Adipose Tissue-Derived Stem Cell Secreted IGF-1 Protects Myoblasts from the Negative Effect of Myostatin

Directory of Open Access Journals (Sweden)

Sebastian Gehmert

2014-01-01

Full Text Available Myostatin, a TGF-β family member, is associated with inhibition of muscle growth and differentiation and might interact with the IGF-1 signaling pathway. Since IGF-1 is secreted at a bioactive level by adipose tissue-derived mesenchymal stem cells (ASCs, these cells (ASCs provide a therapeutic option for Duchenne Muscular Dystrophy (DMD. But the protective effect of stem cell secreted IGF-1 on myoblast under high level of myostatin remains unclear. In the present study murine myoblasts were exposed to myostatin under presence of ASCs conditioned medium and investigated for proliferation and apoptosis. The protective effect of IGF-1 was further examined by using IGF-1 neutralizing and receptor antibodies as well as gene silencing RNAi technology. MyoD expression was detected to identify impact of IGF-1 on myoblasts differentiation when exposed to myostatin. IGF-1 was accountable for 43.6% of the antiapoptotic impact and 48.8% for the proliferative effect of ASCs conditioned medium. Furthermore, IGF-1 restored mRNA and protein MyoD expression of myoblasts under risk. Beside fusion and transdifferentiation the beneficial effect of ASCs is mediated by paracrine secreted cytokines, particularly IGF-1. The present study underlines the potential of ASCs as a therapeutic option for Duchenne muscular dystrophy and other dystrophic muscle diseases.

Hes6 is required for actin cytoskeletal organization in differentiating C2C12 myoblasts

Energy Technology Data Exchange (ETDEWEB)

Malone, Caroline M.P.; Domaschenz, Renae; Amagase, Yoko [MRC Cancer Cell Unit, Hutchison-MRC Research Centre, Addenbrooke' s Hospital, Cambridge CB2 0XZ (United Kingdom); Dunham, Ian [EMBL-European Bioinformatics Institute (EBI), Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SD (United Kingdom); Murai, Kasumi [MRC Cancer Cell Unit, Hutchison-MRC Research Centre, Addenbrooke' s Hospital, Cambridge CB2 0XZ (United Kingdom); Jones, Philip H., E-mail: phj20@cam.ac.uk [MRC Cancer Cell Unit, Hutchison-MRC Research Centre, Addenbrooke' s Hospital, Cambridge CB2 0XZ (United Kingdom)

2011-07-01

Hes6 is a member of the hairy-enhancer-of-split family of transcription factors that regulate proliferating cell fate in development and is known to be expressed in developing muscle. Here we investigate its function in myogenesis in vitro. We show that Hes6 is a direct transcriptional target of the myogenic transcription factors MyoD and Myf5, indicating that it is integral to the myogenic transcriptional program. The localization of Hes6 protein changes during differentiation, becoming predominantly nuclear. Knockdown of Hes6 mRNA levels by siRNA has no effect on cell cycle exit or induction of myosin heavy chain expression in differentiating C2C12 myoblasts, but F-actin filament formation is disrupted and both cell motility and myoblast fusion are reduced. The knockdown phenotype is rescued by expression of Hes6 cDNA resistant to siRNA. These results define a novel role for Hes6 in actin cytoskeletal dynamics in post mitotic myoblasts.

Hes6 is required for actin cytoskeletal organization in differentiating C2C12 myoblasts

International Nuclear Information System (INIS)

Malone, Caroline M.P.; Domaschenz, Renae; Amagase, Yoko; Dunham, Ian; Murai, Kasumi; Jones, Philip H.

2011-01-01

Hes6 is a member of the hairy-enhancer-of-split family of transcription factors that regulate proliferating cell fate in development and is known to be expressed in developing muscle. Here we investigate its function in myogenesis in vitro. We show that Hes6 is a direct transcriptional target of the myogenic transcription factors MyoD and Myf5, indicating that it is integral to the myogenic transcriptional program. The localization of Hes6 protein changes during differentiation, becoming predominantly nuclear. Knockdown of Hes6 mRNA levels by siRNA has no effect on cell cycle exit or induction of myosin heavy chain expression in differentiating C2C12 myoblasts, but F-actin filament formation is disrupted and both cell motility and myoblast fusion are reduced. The knockdown phenotype is rescued by expression of Hes6 cDNA resistant to siRNA. These results define a novel role for Hes6 in actin cytoskeletal dynamics in post mitotic myoblasts.

New perspectives in the treatment of damaged myocardium using autologous skeletal myoblasts

International Nuclear Information System (INIS)

Rigatelli, Gianluca; Rossini, Katia; Vindigni, Vincenzo; Mazzoleni, Francesco; Rigatelli, Giorgio; Carraro, Ugo

2004-01-01

Autologous skeletal myoblast transplantation may be used to ameliorate the healing process following myocardium infarct and, hopefully, cardiomyopathies. Despite successful animal experimentation, several issues need to be addressed in clinical settings, i.e., the impact of the delivery route, the extent of short- and long-term survival, and differentiation of the injected skeletal myoblasts. The authors offer some new hypotheses resulting from basic research, i.e., where and when to inject the myogenic cells, whatever their source, how to decrease new myofiber atrophy and improve their regeneration. Although these new hypotheses still need to be tested in humans, they may be decisive for future experimental studies and will lead to making endovascular cell implantation a more effective way to treat ischemic heart disease and failure

β‐Taxilin participates in differentiation of C2C12 myoblasts into myotubes

Energy Technology Data Exchange (ETDEWEB)

Sakane, Hiroshi; Makiyama, Tomohiko; Nogami, Satoru; Horii, Yukimi [Department of Molecular and Cell Biology, Graduate school of Medicine, Dokkyo Medical University, 880 Kitakobayashi, Mibu-town, Tochigi 321-0293 (Japan); Akasaki, Kenji [Faculty of Pharmacy and Pharmaceutical Sciences, Fukuyama University, Fukuyama, Hiroshima 729-0292 (Japan); Shirataki, Hiromichi, E-mail: hiro-sh@dokkyomed.ac.jp [Department of Molecular and Cell Biology, Graduate school of Medicine, Dokkyo Medical University, 880 Kitakobayashi, Mibu-town, Tochigi 321-0293 (Japan)

2016-07-15

Myogenesis is required for the development of skeletal muscle. Accumulating evidence indicates that the expression of several genes are upregulated during myogenesis and these genes play pivotal roles in myogenesis. However, the molecular mechanism underlying myogenesis is not fully understood. In this study, we found that β-taxilin, which is specifically expressed in the skeletal muscle and heart tissues, was progressively expressed during differentiation of C2C12 myoblasts into myotubes, prompting us to investigate the role of β-taxilin in myogenesis. In C2C12 cells, knockdown of β-taxilin impaired the fusion of myoblasts into myotubes, and decreased the diameter of myotubes. We also found that β-taxilin interacted with dysbindin, a coiled-coil-containing protein. Knockdown of dysbindin conversely promoted the fusion of myoblasts into myotubes and increased the diameter of myotubes in C2C12 cells. Furthermore, knockdown of dysbindin attenuated the inhibitory effect of β-taxilin depletion on myotube formation of C2C12 cells. These results demonstrate that β-taxilin participates in myogenesis through suppressing the function of dysbindin to inhibit the differentiation of C2C12 myoblasts into myotubes. - Highlights: • β‐Taxilin is progressively expressed during differentiation of C2C12 cell. • Knockdown of β-taxilin impaired C2C12 myotube formation. • β‐Taxilin interacted with dysbindin. • Knockdown of dysbindin promoted C2C12 myotube formation. • The function of β-taxilin in C2C12 myotube formation depends on dysbindin.

Electrotransfection and lipofection show comparable efficiency for in vitro gene delivery of primary human myoblasts.

Science.gov (United States)

Mars, Tomaz; Strazisar, Marusa; Mis, Katarina; Kotnik, Nejc; Pegan, Katarina; Lojk, Jasna; Grubic, Zoran; Pavlin, Mojca

2015-04-01

Transfection of primary human myoblasts offers the possibility to study mechanisms that are important for muscle regeneration and gene therapy of muscle disease. Cultured human myoblasts were selected here because muscle cells still proliferate at this developmental stage, which might have several advantages in gene therapy. Gene therapy is one of the most sought-after tools in modern medicine. Its progress is, however, limited due to the lack of suitable gene transfer techniques. To obtain better insight into the transfection potential of the presently used techniques, two non-viral transfection methods--lipofection and electroporation--were compared. The parameters that can influence transfection efficiency and cell viability were systematically approached and compared. Cultured myoblasts were transfected with the pEGFP-N1 plasmid either using Lipofectamine 2000 or with electroporation. Various combinations for the preparation of the lipoplexes and the electroporation media, and for the pulsing protocols, were tested and compared. Transfection efficiency and cell viability were inversely proportional for both approaches. The appropriate ratio of Lipofectamine and plasmid DNA provides optimal conditions for lipofection, while for electroporation, RPMI medium and a pulsing protocol using eight pulses of 2 ms at E = 0.8 kV/cm proved to be the optimal combination. The transfection efficiencies for the optimal lipofection and optimal electrotransfection protocols were similar (32 vs. 32.5%, respectively). Both of these methods are effective for transfection of primary human myoblasts; however, electroporation might be advantageous for in vivo application to skeletal muscle.

Distinct transcriptional networks in quiescent myoblasts: a role for Wnt signaling in reversible vs. irreversible arrest.

Directory of Open Access Journals (Sweden)

Sindhu Subramaniam

Full Text Available Most cells in adult mammals are non-dividing: differentiated cells exit the cell cycle permanently, but stem cells exist in a state of reversible arrest called quiescence. In damaged skeletal muscle, quiescent satellite stem cells re-enter the cell cycle, proliferate and subsequently execute divergent programs to regenerate both post-mitotic myofibers and quiescent stem cells. The molecular basis for these alternative programs of arrest is poorly understood. In this study, we used an established myogenic culture model (C2C12 myoblasts to generate cells in alternative states of arrest and investigate their global transcriptional profiles. Using cDNA microarrays, we compared G0 myoblasts with post-mitotic myotubes. Our findings define the transcriptional program of quiescent myoblasts in culture and establish that distinct gene expression profiles, especially of tumour suppressor genes and inhibitors of differentiation characterize reversible arrest, distinguishing this state from irreversibly arrested myotubes. We also reveal the existence of a tissue-specific quiescence program by comparing G0 C2C12 myoblasts to isogenic G0 fibroblasts (10T1/2. Intriguingly, in myoblasts but not fibroblasts, quiescence is associated with a signature of Wnt pathway genes. We provide evidence that different levels of signaling via the canonical Wnt pathway characterize distinct cellular states (proliferation vs. quiescence vs. differentiation. Moderate induction of Wnt signaling in quiescence is associated with critical properties such as clonogenic self-renewal. Exogenous Wnt treatment subverts the quiescence program and negatively affects clonogenicity. Finally, we identify two new quiescence-induced regulators of canonical Wnt signaling, Rgs2 and Dkk3, whose induction in G0 is required for clonogenic self-renewal. These results support the concept that active signal-mediated regulation of quiescence contributes to stem cell properties, and have implications for

Distinct transcriptional networks in quiescent myoblasts: a role for Wnt signaling in reversible vs. irreversible arrest.

Science.gov (United States)

Subramaniam, Sindhu; Sreenivas, Prethish; Cheedipudi, Sirisha; Reddy, Vatrapu Rami; Shashidhara, Lingadahalli Subrahmanya; Chilukoti, Ravi Kumar; Mylavarapu, Madhavi; Dhawan, Jyotsna

2014-01-01

Most cells in adult mammals are non-dividing: differentiated cells exit the cell cycle permanently, but stem cells exist in a state of reversible arrest called quiescence. In damaged skeletal muscle, quiescent satellite stem cells re-enter the cell cycle, proliferate and subsequently execute divergent programs to regenerate both post-mitotic myofibers and quiescent stem cells. The molecular basis for these alternative programs of arrest is poorly understood. In this study, we used an established myogenic culture model (C2C12 myoblasts) to generate cells in alternative states of arrest and investigate their global transcriptional profiles. Using cDNA microarrays, we compared G0 myoblasts with post-mitotic myotubes. Our findings define the transcriptional program of quiescent myoblasts in culture and establish that distinct gene expression profiles, especially of tumour suppressor genes and inhibitors of differentiation characterize reversible arrest, distinguishing this state from irreversibly arrested myotubes. We also reveal the existence of a tissue-specific quiescence program by comparing G0 C2C12 myoblasts to isogenic G0 fibroblasts (10T1/2). Intriguingly, in myoblasts but not fibroblasts, quiescence is associated with a signature of Wnt pathway genes. We provide evidence that different levels of signaling via the canonical Wnt pathway characterize distinct cellular states (proliferation vs. quiescence vs. differentiation). Moderate induction of Wnt signaling in quiescence is associated with critical properties such as clonogenic self-renewal. Exogenous Wnt treatment subverts the quiescence program and negatively affects clonogenicity. Finally, we identify two new quiescence-induced regulators of canonical Wnt signaling, Rgs2 and Dkk3, whose induction in G0 is required for clonogenic self-renewal. These results support the concept that active signal-mediated regulation of quiescence contributes to stem cell properties, and have implications for pathological

Gene trapping in differentiating cell lines: regulation of the lysosomal protease cathepsin B in skeletal myoblast growth and fusion.

Science.gov (United States)

Gogos, J A; Thompson, R; Lowry, W; Sloane, B F; Weintraub, H; Horwitz, M

1996-08-01

To identify genes regulated during skeletal muscle differentiation, we have infected mouse C2C12 myoblasts with retroviral gene trap vectors, containing a promoterless marker gene with a 5' splice acceptor signal. Integration of the vector adjacent to an actively transcribed gene places the marker under the transcriptional control of the endogenous gene, while the adjacent vector sequences facilitate cloning. The vector insertionally mutates the trapped locus and may also form fusion proteins with the endogenous gene product. We have screened several hundred clones, each containing a trapping vector integrated into a different endogenous gene. In agreement with previous estimates based on hybridization kinetics, we find that a large proportion of all genes expressed in myoblasts are regulated during differentiation. Many of these genes undergo unique temporal patterns of activation or repression during cell growth and myotube formation, and some show specific patterns of subcellular localization. The first gene we have identified with this strategy is the lysosomal cysteine protease cathepsin B. Expression from the trapped allele is upregulated during early myoblast fusion and downregulated in myotubes. A direct role for cathepsin B in myoblast growth and fusion is suggested by the observation that the trapped cells deficient in cathepsin B activity have an unusual morphology and reduced survival in low-serum media and undergo differentiation with impaired cellular fusion. The phenotype is reproduced by antisense cathepsin B expression in parental C2C12 myoblasts. The cellular phenotype is similar to that observed in cultured myoblasts from patients with I cell disease, in which there is diminished accumulation of lysosomal enzymes. This suggests that a specific deficiency of cathepsin B could contribute to the myopathic component of this illness.

Concordant but Varied Phenotypes among Duchenne Muscular Dystrophy Patient-Specific Myoblasts Derived using a Human iPSC-Based Model

Directory of Open Access Journals (Sweden)

In Young Choi

2016-06-01

Full Text Available Duchenne muscular dystrophy (DMD remains an intractable genetic disease. Althogh there are several animal models of DMD, there is no human cell model that carries patient-specific DYSTROPHIN mutations. Here, we present a human DMD model using human induced pluripotent stem cells (hiPSCs. Our model reveals concordant disease-related phenotypes with patient-dependent variation, which are partially reversed by genetic and pharmacological approaches. Our “chemical-compound-based” strategy successfully directs hiPSCs into expandable myoblasts, which exhibit a myogenic transcriptional program, forming striated contractile myofibers and participating in muscle regeneration in vivo. DMD-hiPSC-derived myoblasts show disease-related phenotypes with patient-to-patient variability, including aberrant expression of inflammation or immune-response genes and collagens, increased BMP/TGFβ signaling, and reduced fusion competence. Furthermore, by genetic correction and pharmacological “dual-SMAD” inhibition, the DMD-hiPSC-derived myoblasts and genetically corrected isogenic myoblasts form “rescued” multi-nucleated myotubes. In conclusion, our findings demonstrate the feasibility of establishing a human “DMD-in-a-dish” model using hiPSC-based disease modeling.

PKC-Mediated ZYG1 Phosphorylation Induces Fusion of Myoblasts as well as of Dictyostelium Cells

Directory of Open Access Journals (Sweden)

Aiko Amagai

2012-01-01

Full Text Available We have previously demonstrated that a novel protein ZYG1 induces sexual cell fusion (zygote formation of Dictyostelium cells. In the process of cell fusion, involvements of signal transduction pathways via Ca2+ and PKC (protein kinase C have been suggested because zygote formation is greatly enhanced by PKC activators. In fact, there are several deduced sites phosphorylated by PKC in ZYG1 protein. Thereupon, we designed the present work to examine whether or not ZYG1 is actually phosphorylated by PKC and localized at the regions of cell-cell contacts where cell fusion occurs. These were ascertained, suggesting that ZYG1 might be the target protein for PKC. A humanized version of zyg1 cDNA (mzyg1 was introduced into myoblasts to know if ZYG1 is also effective in cell fusion of myoblasts. Quite interestingly, enforced expression of ZYG1 in myoblasts was found to induce markedly their cell fusion, thus strongly suggesting the existence of a common signaling pathway for cell fusion beyond the difference of species.

Hypoxia induces adipogenic differentitation of myoblastic cell lines

Energy Technology Data Exchange (ETDEWEB)

Itoigawa, Yoshiaki [Tohoku University School of Medicine, Sendai (Japan); Juntendo University School of Medicine, Tokyo (Japan); Kishimoto, Koshi N., E-mail: kishimoto@med.tohoku.ac.jp [Tohoku University School of Medicine, Sendai (Japan); Okuno, Hiroshi; Sano, Hirotaka [Tohoku University School of Medicine, Sendai (Japan); Kaneko, Kazuo [Juntendo University School of Medicine, Tokyo (Japan); Itoi, Eiji [Tohoku University School of Medicine, Sendai (Japan)

2010-09-03

Research highlights: {yields} C2C12 and G8 myogenic cell lines treated by hypoxia differentiate into adipocytes. {yields} The expression of C/EBP{beta}, {alpha} and PPAR{gamma} were increased under hypoxia. {yields} Myogenic differentiation of C2C12 was inhibited under hypoxia. -- Abstract: Muscle atrophy usually accompanies fat accumulation in the muscle. In such atrophic conditions as back muscles of kyphotic spine and the rotator cuff muscles with torn tendons, blood flow might be diminished. It is known that hypoxia causes trans-differentiation of mesenchymal stem cells derived from bone marrow into adipocytes. However, it has not been elucidated yet if hypoxia turned myoblasts into adipocytes. We investigated adipogenesis in C2C12 and G8 murine myogenic cell line treated by hypoxia. Cells were also treated with the cocktail of insulin, dexamethasone and IBMX (MDI), which has been known to inhibit Wnt signaling and promote adipogenesis. Adipogenic differentiation was seen in both hypoxia and MDI. Adipogenic marker gene expression was assessed in C2C12. CCAAT/enhancer-binding protein (C/EBP) {beta}, {alpha} and peroxisome proliferator activating receptor (PPAR) {gamma} were increased by both hypoxia and MDI. The expression profile of Wnt10b was different between hypoxia and MDI. The mechanism for adipogenesis of myoblasts in hypoxia might be regulated by different mechanism than the modification of Wnt signaling.

Concordant but Varied Phenotypes among Duchenne Muscular Dystrophy Patient-Specific Myoblasts Derived using a Human iPSC-Based Model.

Science.gov (United States)

Choi, In Young; Lim, HoTae; Estrellas, Kenneth; Mula, Jyothi; Cohen, Tatiana V; Zhang, Yuanfan; Donnelly, Christopher J; Richard, Jean-Philippe; Kim, Yong Jun; Kim, Hyesoo; Kazuki, Yasuhiro; Oshimura, Mitsuo; Li, Hongmei Lisa; Hotta, Akitsu; Rothstein, Jeffrey; Maragakis, Nicholas; Wagner, Kathryn R; Lee, Gabsang

2016-06-07

Duchenne muscular dystrophy (DMD) remains an intractable genetic disease. Althogh there are several animal models of DMD, there is no human cell model that carries patient-specific DYSTROPHIN mutations. Here, we present a human DMD model using human induced pluripotent stem cells (hiPSCs). Our model reveals concordant disease-related phenotypes with patient-dependent variation, which are partially reversed by genetic and pharmacological approaches. Our "chemical-compound-based" strategy successfully directs hiPSCs into expandable myoblasts, which exhibit a myogenic transcriptional program, forming striated contractile myofibers and participating in muscle regeneration in vivo. DMD-hiPSC-derived myoblasts show disease-related phenotypes with patient-to-patient variability, including aberrant expression of inflammation or immune-response genes and collagens, increased BMP/TGFβ signaling, and reduced fusion competence. Furthermore, by genetic correction and pharmacological "dual-SMAD" inhibition, the DMD-hiPSC-derived myoblasts and genetically corrected isogenic myoblasts form "rescued" multi-nucleated myotubes. In conclusion, our findings demonstrate the feasibility of establishing a human "DMD-in-a-dish" model using hiPSC-based disease modeling. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Injectable scaffold materials differ in their cell instructive effects on primary human myoblasts

DEFF Research Database (Denmark)

Hejbøl, Eva Kildall; Sellathurai, Jeeva; Nair, Prabha Damodaran

2017-01-01

Scaffolds are materials used for delivery of cells for regeneration of tissues. They support three-dimensional organization and improve cell survival. For the repair of small skeletal muscles, injections of small volumes of cells are attractive, and injectable scaffolds for delivery of cells offer...... a minimally invasive technique. In this study, we examined in vitro the cell instructive effects of three types of injectable scaffolds, fibrin, alginate, and poly(lactic-co-glycolic acid)-based microparticles on primary human myoblasts. The myoblast morphology and progression in the myogenic program differed......, depending on the type of scaffold material. In alginate gel, the cells obtained a round morphology, they ceased to proliferate, and entered quiescence. In the fibrin gels, differentiation was promoted, and myotubes were observed within a few days in culture, while poly(lactic-co-glycolic acid...

Black ginseng activates Akt signaling, thereby enhancing myoblast differentiation and myotube growth

Directory of Open Access Journals (Sweden)

Soo-Yeon Lee

2018-01-01

Conclusion: BG enhances myoblast differentiation and myotube hypertrophy by activating Akt/mTOR/p70S6k axis. Thus, our study demonstrates that BG has promising potential to treat or prevent muscle loss related to aging or other pathological conditions, such as diabetes.

Six1 induces protein synthesis signaling expression in duck myoblasts mainly via up-regulation of mTOR

Directory of Open Access Journals (Sweden)

Haohan Wang

2016-03-01

Full Text Available Abstract As a critical transcription factor, Six1 plays an important role in the regulation of myogenesis and muscle development. However, little is known about its regulatory mechanism associated with muscular protein synthesis. The objective of this study was to investigate the effects of overexpression ofSix1 on the expression of key protein metabolism-related genes in duck myoblasts. Through an experimental model where duck myoblasts were transfected with a pEGFP-duSix1 construct, we found that overexpression of duckSix1 could enhance cell proliferation activity and increase mRNA expression levels of key genes involved in the PI3K/Akt/mTOR signaling pathway, while the expression of FOXO1, MuRF1and MAFbx was not significantly altered, indicating thatSix1 could promote protein synthesis in myoblasts through up-regulating the expression of several related genes. Additionally, in duck myoblasts treated with LY294002 and rapamycin, the specific inhibitors ofPI3K and mTOR, respectively, the overexpression of Six1 could significantly ameliorate inhibitive effects of these inhibitors on protein synthesis. Especially, the mRNA expression levels of mTOR and S6K1 were observed to undergo a visible change, and a significant increase in protein expression of S6K1 was seen. These data suggested that Six1plays an important role in protein synthesis, which may be mainly due to activation of the mTOR signaling pathway.

Mesenchymal Stromal Cell Secreted Sphingosine 1-Phosphate (S1P) Exerts a Stimulatory Effect on Skeletal Myoblast Proliferation

Science.gov (United States)

Tani, Alessia; Anderloni, Giulia; Pierucci, Federica; Matteini, Francesca; Chellini, Flaminia; Zecchi Orlandini, Sandra; Meacci, Elisabetta

2014-01-01

Bone-marrow-derived mesenchymal stromal cells (MSCs) have the potential to significantly contribute to skeletal muscle healing through the secretion of paracrine factors that support proliferation and enhance participation of the endogenous muscle stem cells in the process of repair/regeneration. However, MSC-derived trophic molecules have been poorly characterized. The aim of this study was to investigate paracrine signaling effects of MSCs on skeletal myoblasts. It was found, using a biochemical and morphological approach that sphingosine 1-phosphate (S1P), a natural bioactive lipid exerting a broad range of muscle cell responses, is secreted by MSCs and represents an important factor by which these cells exert their stimulatory effects on C2C12 myoblast and satellite cell proliferation. Indeed, exposure to conditioned medium obtained from MSCs cultured in the presence of the selective sphingosine kinase inhibitor (iSK), blocked increased cell proliferation caused by the conditioned medium from untreated MSCs, and the addition of exogenous S1P in the conditioned medium from MSCs pre-treated with iSK further increased myoblast proliferation. Finally, we also demonstrated that the myoblast response to MSC-secreted vascular endothelial growth factor (VEGF) involves the release of S1P from C2C12 cells. Our data may have important implications in the optimization of cell-based strategies to promote skeletal muscle regeneration. PMID:25264785

Actin-associated protein palladin is required for migration behavior and differentiation potential of C2C12 myoblast cells

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Ngoc Uyen Nhi; Liang, Vincent Roderick; Wang, Hao-Ven, E-mail: hvwang@mail.ncku.edu.tw

2014-09-26

Highlights: • Palladin is involved in myogenesis in vitro. • Palladin knockdown by siRNA increases myoblast proliferation, viability and differentiation. • Palladin knockdown decreases C2C12 myoblast migration ability. - Abstract: The actin-associated protein palladin has been shown to be involved in differentiation processes in non-muscle tissues. However, but its function in skeletal muscle has rarely been studied. Palladin plays important roles in the regulation of diverse actin-related signaling in a number of cell types. Since intact actin-cytoskeletal remodeling is necessary for myogenesis, in the present study, we pursue to investigate the role of actin-associated palladin in skeletal muscle differentiation. Palladin in C2C12 myoblasts is knocked-down using specific small interfering RNA (siRNA). The results show that down-regulation of palladin decreased migratory activity of mouse skeletal muscle C2C12 myoblasts. Furthermore, the depletion of palladin enhances C2C12 vitality and proliferation. Of note, the loss of palladin promotes C2C12 to express the myosin heavy chain, suggesting that palladin has a role in the modulation of C2C12 differentiation. It is thus proposed that palladin is required for normal C2C12 myogenesis in vitro.

Actin-associated protein palladin is required for migration behavior and differentiation potential of C2C12 myoblast cells

International Nuclear Information System (INIS)

Nguyen, Ngoc Uyen Nhi; Liang, Vincent Roderick; Wang, Hao-Ven

2014-01-01

Highlights: • Palladin is involved in myogenesis in vitro. • Palladin knockdown by siRNA increases myoblast proliferation, viability and differentiation. • Palladin knockdown decreases C2C12 myoblast migration ability. - Abstract: The actin-associated protein palladin has been shown to be involved in differentiation processes in non-muscle tissues. However, but its function in skeletal muscle has rarely been studied. Palladin plays important roles in the regulation of diverse actin-related signaling in a number of cell types. Since intact actin-cytoskeletal remodeling is necessary for myogenesis, in the present study, we pursue to investigate the role of actin-associated palladin in skeletal muscle differentiation. Palladin in C2C12 myoblasts is knocked-down using specific small interfering RNA (siRNA). The results show that down-regulation of palladin decreased migratory activity of mouse skeletal muscle C2C12 myoblasts. Furthermore, the depletion of palladin enhances C2C12 vitality and proliferation. Of note, the loss of palladin promotes C2C12 to express the myosin heavy chain, suggesting that palladin has a role in the modulation of C2C12 differentiation. It is thus proposed that palladin is required for normal C2C12 myogenesis in vitro

Mast cell tryptase stimulates myoblast proliferation; a mechanism relying on protease-activated receptor-2 and cyclooxygenase-2

Directory of Open Access Journals (Sweden)

Côté Claude H

2011-10-01

Full Text Available Abstract Background Mast cells contribute to tissue repair in fibrous tissues by stimulating proliferation of fibroblasts through the release of tryptase which activates protease-activated receptor-2 (PAR-2. The possibility that a tryptase/PAR-2 signaling pathway exists in skeletal muscle cell has never been investigated. The aim of this study was to evaluate whether tryptase can stimulate myoblast proliferation and determine the downstream cascade. Methods Proliferation of L6 rat skeletal myoblasts stimulated with PAR-2 agonists (tryptase, trypsin and SLIGKV was assessed. The specificity of the tryptase effect was evaluated with a specific inhibitor, APC-366. Western blot analyses were used to evaluate the expression and functionality of PAR-2 receptor and to assess the expression of COX-2. COX-2 activity was evaluated with a commercial activity assay kit and by measurement of PGF2α production. Proliferation assays were also performed in presence of different prostaglandins (PGs. Results Tryptase increased L6 myoblast proliferation by 35% above control group and this effect was completely inhibited by APC-366. We confirmed the expression of PAR-2 receptor in vivo in skeletal muscle cells and in satellite cells and in vitro in L6 cells, where PAR-2 was found to be functional. Trypsin and SLIGKV increased L6 cells proliferation by 76% and 26% above control, respectively. COX-2 activity was increased following stimulation with PAR-2 agonist but its expression remained unchanged. Inhibition of COX-2 activity by NS-398 abolished the stimulation of cell proliferation induced by tryptase and trypsin. Finally, 15-deoxy-Δ-12,14-prostaglandin J2 (15Δ-PGJ2, a product of COX-2-derived prostaglandin D2, stimulated myoblast proliferation, but not PGE2 and PGF2α. Conclusions Taken together, our data show that tryptase can stimulate myoblast proliferation and this effect is part of a signaling cascade dependent on PAR-2 activation and on the downstream

Mitophagy is required for mitochondrial biogenesis and myogenic differentiation of C2C12 myoblasts.

Science.gov (United States)

Sin, Jon; Andres, Allen M; Taylor, David J R; Weston, Thomas; Hiraumi, Yoshimi; Stotland, Aleksandr; Kim, Brandon J; Huang, Chengqun; Doran, Kelly S; Gottlieb, Roberta A

2016-01-01

Myogenesis is a crucial process governing skeletal muscle development and homeostasis. Differentiation of primitive myoblasts into mature myotubes requires a metabolic switch to support the increased energetic demand of contractile muscle. Skeletal myoblasts specifically shift from a highly glycolytic state to relying predominantly on oxidative phosphorylation (OXPHOS) upon differentiation. We have found that this phenomenon requires dramatic remodeling of the mitochondrial network involving both mitochondrial clearance and biogenesis. During early myogenic differentiation, autophagy is robustly upregulated and this coincides with DNM1L/DRP1 (dynamin 1-like)-mediated fragmentation and subsequent removal of mitochondria via SQSTM1 (sequestosome 1)-mediated mitophagy. Mitochondria are then repopulated via PPARGC1A/PGC-1α (peroxisome proliferator-activated receptor gamma, coactivator 1 alpha)-mediated biogenesis. Mitochondrial fusion protein OPA1 (optic atrophy 1 [autosomal dominant]) is then briskly upregulated, resulting in the reformation of mitochondrial networks. The final product is a myotube replete with new mitochondria. Respirometry reveals that the constituents of these newly established mitochondrial networks are better primed for OXPHOS and are more tightly coupled than those in myoblasts. Additionally, we have found that suppressing autophagy with various inhibitors during differentiation interferes with myogenic differentiation. Together these data highlight the integral role of autophagy and mitophagy in myogenic differentiation.

Effects of creatine and its analog, β-guanidinopropionic acid, on the differentiation of and nucleoli in myoblasts.

Science.gov (United States)

Ohira, Yoshinobu; Matsuoka, Yoshikazu; Kawano, Fuminori; Ogura, Akihiko; Higo, Yoko; Ohira, Takashi; Terada, Masahiro; Oke, Yoshihiko; Nakai, Naoya

2011-01-01

The effects of supplementation with creatine (Cr) and its analog, β-guanidinopropionic acid (β-GPA), on the differentiation of myoblasts and the numbers of nucleoli were studied in C2C12 cells. The cells were cultured in differentiation medium for 4 d. Then Cr (1 mM) or β-GPA (1 mM) was added to the cells, and the mixture was cultured for an additional 2 d. Although the number of myotubes was not different among the groups, myotube diameters and nuclear numbers in myotubes were increased by Cr and β-GPA treatment respectively. The expression of differentiation marker proteins, myogenin, and the myosine heavy chain, was increased in the β-GPA group. Supplementation with β-GPA also increased the percentage of p21 (inhibitor for cell cycle progression)-positive myoblasts. Supplementation with Cr inhibited the decrease in nucleoli numbers, whereas β-GPA increased nucleolar sizes in the myotubes. These results suggest that β-GPA supplementation stimulated the differentiation of myoblasts into multi-nucleated myotubes through induction of p21 expression.

Biphasic regulation of intracellular calcium by gemfibrozil contributes to inhibiting L6 myoblast differentiation: implications for clinical myotoxicity.

Science.gov (United States)

Liu, Aiming; Yang, Julin; Gonzalez, Frank J; Cheng, Gary Q; Dai, Renke

2011-02-18

Gemfibrozil is the most myotoxic fibrate drug commonly used for dyslipidemia, but the mechanism is poorly understood. The current study revealed that gemfibrozil inhibits myoblast differentiation through the regulation of intracellular calcium ([Ca(2+)]i) as revealed in L6 myoblasts by use of laser scan confocal microscopy and flow cytometry using Fluo-4 AM as a probe. Gemfibrozil at 20-400 μM, could regulate [Ca(2+)]i in L6 cells in a biphasic manner, and sustained reduction was observed when the concentration reached 200 μM. Inhibition of L6 differentiation by gemfibrozil was concentration-dependent with maximal effect noted between 200 and 400 μM, as indicated by creatine kinase activities and the differentiation index, respectively. In differentiating L6 myoblasts, gemfibrozil at concentrations below 400 μM led to no significant signs of apoptosis or cytotoxicity, whereas differentiation, inhibited by 200 μM gemfibrozil, was only partially recovered. A good correlation was noted between gemfibrozil concentrations that regulate [Ca(2+)]i and inhibit L6 myoblasts differentiation, and both are within the range of total serum concentrations found in the clinic. These data suggest a potential pharmacodynamic effect of gemfibrozil on myogenesis as a warning sign, in addition to the complex pharmacokinetic interactions. It is also noteworthy that mobilization of [Ca(2+)]i by gemfibrozil may trigger complex biological responses besides myocyte differentiation. Information revealed in this study explores the mechanism of gemfibrozil-induced myotoxicity through the regulation of intracellular calcium.

MiRNA-199a-3p Regulates C2C12 Myoblast Differentiation through IGF-1/AKT/mTOR Signal Pathway

Directory of Open Access Journals (Sweden)

Long Jia

2013-12-01

Full Text Available MicroRNAs constitute a class of ~22-nucleotide non-coding RNAs. They modulate gene expression by associating with the 3' untranslated regions (3' UTRs of messenger RNAs (mRNAs. Although multiple miRNAs are known to be regulated during myoblast differentiation, their individual roles in muscle development are still not fully understood. In this study, we showed that miR-199a-3p was highly expressed in skeletal muscle and was induced during C2C12 myoblasts differentiation. We also identified and confirmed several genes of the IGF-1/AKT/mTOR signal pathway, including IGF-1, mTOR, and RPS6KA6, as important cellular targets of miR-199a-3p in myoblasts. Overexpression of miR-199a-3p partially blocked C2C12 myoblast differentiation and the activation of AKT/mTOR signal pathway, while interference of miR-199a-3p by antisense oligonucleotides promoted C2C12 differentiation and myotube hypertrophy. Thus, our studies have established miR-199a-3p as a potential regulator of myogenesis through the suppression of IGF-1/AKT/mTOR signal pathway.

Isolation and Characterization of Human Myoblast Culture In Vitro for Technologies of Cell and Gene Therapy of Skeletal Muscle Pathologies.

Science.gov (United States)

Tabakov, V Yu; Zinov'eva, O E; Voskresenskaya, O N; Skoblov, M Yu

2018-03-01

We analyzed cultures of 5 independent myoblast lines from human skeletal muscles. It was shown that the content of desmin-positive cells in cultures at early passages exceeds 90%. Typical morphofunctional signs of myogenic differentiation disturbances were identified and their dynamics was studied. Signs of alternative adipogenic and chondrogenic differentiation of cells were revealed. Based on these data, limitations for the use of myoblast cultures of certain passages for biomedical research and cell therapy were evaluated.

Gallic acid prevents isoproterenol-induced cardiac hypertrophy and fibrosis through regulation of JNK2 signaling and Smad3 binding activity

Science.gov (United States)

Ryu, Yuhee; Jin, Li; Kee, Hae Jin; Piao, Zhe Hao; Cho, Jae Yeong; Kim, Gwi Ran; Choi, Sin Young; Lin, Ming Quan; Jeong, Myung Ho

2016-01-01

Gallic acid, a type of phenolic acid, has been shown to have beneficial effects in inflammation, vascular calcification, and metabolic diseases. The present study was aimed at determining the effect and regulatory mechanism of gallic acid in cardiac hypertrophy and fibrosis. Cardiac hypertrophy was induced by isoproterenol (ISP) in mice and primary neonatal cardiomyocytes. Gallic acid pretreatment attenuated concentric cardiac hypertrophy. It downregulated the expression of atrial natriuretic peptide, brain natriuretic peptide, and beta-myosin heavy chain in vivo and in vitro. Moreover, it prevented interstitial collagen deposition and expression of fibrosis-associated genes. Upregulation of collagen type I by Smad3 overexpression was observed in cardiac myoblast H9c2 cells but not in cardiac fibroblasts. Gallic acid reduced the DNA binding activity of phosphorylated Smad3 in Smad binding sites of collagen type I promoter in rat cardiac fibroblasts. Furthermore, it decreased the ISP-induced phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal regulated kinase (ERK) protein in mice. JNK2 overexpression reduced collagen type I and Smad3 expression as well as GATA4 expression in H9c2 cells and cardiac fibroblasts. Gallic acid might be a novel therapeutic agent for the prevention of cardiac hypertrophy and fibrosis by regulating the JNK2 and Smad3 signaling pathway. PMID:27703224

Textile-templated electrospun anisotropic scaffolds for regenerative cardiac tissue engineering.

Science.gov (United States)

Şenel Ayaz, H Gözde; Perets, Anat; Ayaz, Hasan; Gilroy, Kyle D; Govindaraj, Muthu; Brookstein, David; Lelkes, Peter I

2014-10-01

For patients with end-stage heart disease, the access to heart transplantation is limited due to the shortage of donor organs and to the potential for rejection of the donated organ. Therefore, current studies focus on bioengineering approaches for creating biomimetic cardiac patches that will assist in restoring cardiac function, by repairing and/or regenerating the intrinsically anisotropic myocardium. In this paper we present a simplified, straightforward approach for creating bioactive anisotropic cardiac patches, based on a combination of bioengineering and textile-manufacturing techniques in concert with nano-biotechnology based tissue-engineering stratagems. Using knitted conventional textiles, made of cotton or polyester yarns as template targets, we successfully electrospun anisotropic three-dimensional scaffolds from poly(lactic-co-glycolic) acid (PLGA), and thermoplastic polycarbonate-urethane (PCU, Bionate(®)). The surface topography and mechanical properties of textile-templated anisotropic scaffolds significantly differed from those of scaffolds electrospun from the same materials onto conventional 2-D flat-target electrospun scaffolds. Anisotropic textile-templated scaffolds electrospun from both PLGA and PCU, supported the adhesion and proliferation of H9C2 cardiac myoblasts cell line, and guided the cardiac tissue-like anisotropic organization of these cells in vitro. All cell-seeded PCU scaffolds exhibited mechanical properties comparable to those of a human heart, but only the cells on the polyester-templated scaffolds exhibited prolonged spontaneous synchronous contractility on the entire engineered construct for 10 days in vitro at a near physiologic frequency of ∼120 bpm. Taken together, the methods described here take advantage of straightforward established textile manufacturing strategies as an efficient and cost-effective approach to engineering 3D anisotropic, elastomeric PCU scaffolds that can serve as a cardiac patch. Copyright �

Patterning Muscles Using Organizers: Larval Muscle Templates and Adult Myoblasts Actively Interact to Pattern the Dorsal Longitudinal Flight Muscles of Drosophila

Science.gov (United States)

Roy, Sudipto; VijayRaghavan, K.

1998-01-01

Pattern formation in muscle development is often mediated by special cells called muscle organizers. During metamorphosis in Drosophila, a set of larval muscles function as organizers and provide scaffolding for the development of the dorsal longitudinal flight muscles. These organizers undergo defined morphological changes and dramatically split into templates as adult fibers differentiate during pupation. We have investigated the cellular mechanisms involved in the use of larval fibers as templates. Using molecular markers that label myoblasts and the larval muscles themselves, we show that splitting of the larval muscles is concomitant with invasion by imaginal myoblasts and the onset of differentiation. We show that the Erect wing protein, an early marker of muscle differentiation, is not only expressed in myoblasts just before and after fusion, but also in remnant larval nuclei during muscle differentiation. We also show that interaction between imaginal myoblasts and larval muscles is necessary for transformation of the larval fibers. In the absence of imaginal myoblasts, the earliest steps in metamorphosis, such as the escape of larval muscles from histolysis and changes in their innervation, are normal. However, subsequent events, such as the splitting of these muscles, fail to progress. Finally, we show that in a mutant combination, null for Erect wing function in the mesoderm, the splitting of the larval muscles is aborted. These studies provide a genetic and molecular handle for the understanding of mechanisms underlying the use of muscle organizers in muscle patterning. Since the use of such organizers is a common theme in myogenesis in several organisms, it is likely that many of the processes that we describe are conserved. PMID:9606206

Analysis of Mitochondrial Network Morphology in Cultured Myoblasts from Patients with Mitochondrial Disorders

Czech Academy of Sciences Publication Activity Database

Sládková, J.; Spáčilová, J.; Čapek, Martin; Tesařová, M.; Hansíková, H.; Honzík, T.; Martínek, J.; Zámečník, J.; Kostková, O.; Zeman, J.

2015-01-01

Roč. 39, č. 5 (2015), s. 340-350 ISSN 0191-3123 R&D Projects: GA ČR(CZ) GB14-36804G; GA MŠk(CZ) LH13028 Institutional support: RVO:67985823 Keywords : cristae * Fiji * image analysis * mitochondrial disorders * myoblasts * ultrastructure Subject RIV: EA - Cell Biology Impact factor: 0.828, year: 2015

Sphingosine kinase/sphingosine 1-phosphate axis: a new player for insulin-like growth factor-1-induced myoblast differentiation

Directory of Open Access Journals (Sweden)

Bernacchioni Caterina

2012-07-01

Full Text Available Abstract Background Insulin-like growth factor-1 (IGF-1 is the most important physiological regulator of skeletal muscle progenitor cells, which are responsible for adult skeletal muscle regeneration. The ability of IGF-1 to affect multiple aspects of skeletal muscle cell biology such as proliferation, differentiation, survival and motility is well recognized, although the molecular mechanisms implicated in its complex biological action are not fully defined. Since sphingosine 1-phosphate (S1P has recently emerged as a key player in skeletal muscle regeneration, we investigated the possible involvement of the sphingosine kinase (SK/S1P receptor axis on the biological effects of IGF-1 in murine myoblasts. Methods RNA interference, chemical inhibition and immunofluorescence approaches were used to assess the role of the SK/S1P axis on the myogenic and mitogenic effects of IGF-1 in C2C12 myoblasts. Results We show that IGF-1 increases SK activity in mouse myoblasts. The effect of the growth factor does not involve transcriptional regulation of SK1 or SK2, since the protein content of both isoforms is not affected; rather, IGF-1 enhances the fraction of the active form of SK. Moreover, transactivation of the S1P2 receptor induced by IGF-1 via SK activation appears to be involved in the myogenic effect of the growth factor. Indeed, the pro-differentiating effect of IGF-1 in myoblasts is impaired when SK activity is pharmacologically inhibited, or SK1 or SK2 are specifically silenced, or the S1P2 receptor is downregulated. Furthermore, in this study we show that IGF-1 transactivates S1P1/S1P3 receptors via SK activation and that this molecular event negatively regulates the mitogenic effect elicited by the growth factor, since the specific silencing of S1P1 or S1P3 receptors increases cell proliferation induced by IGF-1. Conclusions We demonstrate a dual role of the SK/S1P axis in response to myoblast challenge with IGF-1, that likely is important to

Signals of Ezh2, Src, and Akt Involve in Myostatin-Pax7 Pathways Regulating the Myogenic Fate Determination during the Sheep Myoblast Proliferation and Differentiation

Science.gov (United States)

Li, Li; Liu, Ruizao; Zhang, Li; Zhao, Fuping; Lu, Jian; Zhang, Xiaoning; Du, Lixin

2015-01-01

Myostatin and Pax7 have been well documented individually, however, the mechanism by which Myostatin regulates Pax7 is seldom reported. Here, based on muscle transcriptome analysis in Texel (Myostatin mutant) and Ujumqin (wild type) sheep across the five fetal stages, we constructed and examined the Myostatin-Pax7 pathways in muscle. Then we validated the signals by RNAi in the proliferating and differentiating sheep myoblasts in vitro at mRNA, protein, and cell morphological levels. We reveal that Myostatin signals to Pax7 at least through Ezh2, Src, and Akt during the sheep myoblast proliferation and differentiation. Other signals such as p38MAPK, mTOR, Erk1/2, Wnt, Bmp2, Smad, Tgfb1, and p21 are most probably involved in the Myostatin-affected myogenic events. Myostatin knockdown significantly reduces the counts of nucleus and myotube, but not the fusion index of myoblasts during cell differentiation. In addition, findings also indicate that Myostatin is required for normal myogenic differentiation of the sheep myoblasts, which is different from the C2C12 myoblasts. We expand the regulatory network of Myostatin-Pax7 pathways and first illustrate that Myostatin as a global regulator participates in the epigenetic events involved in myogenesis, which contributes to understand the molecular mechanism of Myostatin in regulation of myogenesis. PMID:25811841

Possible role of TIEG1 as a feedback regulator of myostatin and TGF-{beta} in myoblasts

Energy Technology Data Exchange (ETDEWEB)

Miyake, Masato; Hayashi, Shinichiro; Iwasaki, Shunsuke; Chao, Guozheng; Takahashi, Hideyuki; Watanabe, Kouichi; Ohwada, Shyuichi; Aso, Hisashi [Laboratory of Functional Morphology, Department of Animal Biology, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-Ku, Sendai 981-8555 (Japan); Yamaguchi, Takahiro, E-mail: ty1010@bios.tohoku.ac.jp [Laboratory of Functional Morphology, Department of Animal Biology, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-Ku, Sendai 981-8555 (Japan)

2010-03-19

Myostatin and TGF-{beta} negatively regulate skeletal muscle development and growth. Both factors signal through the Smad2/3 pathway. However, the regulatory mechanism of myostatin and TGF-{beta} signaling remains unclear. TGF-{beta} inducible early gene (TIEG) 1 is highly expressed in skeletal muscle and has been implicated in the modulation of TGF-{beta} signaling. These findings prompted us to investigate the effect of TIEG1 on myostatin and TGF-{beta} signaling using C2C12 myoblasts. Myostatin and TGF-{beta} induced the expression of TIEG1 and Smad7 mRNAs, but not TIEG2 mRNA, in proliferating C2C12 cells. When differentiating C2C12 myoblasts were stimulated by myostatin, TIEG1 mRNA was up-regulated at a late stage of differentiation. In contrast, TGF-{beta} enhanced TIEG1 expression at an early stage. Overexpression of TIEG1 prevented the transcriptional activation of Smad by myostatin and TGF-{beta} in both proliferating or differentiating C2C12 cells, but the expression of Smad2 and Smad7 mRNAs was not affected. Forced expression of TIEG1 inhibited myogenic differentiation but did not cause more inhibition than the empty vector in the presence of myostatin or TGF-{beta}. These results demonstrate that TIEG1 is one possible feedback regulator of myostatin and TGF-{beta} that prevents excess action in myoblasts.

MicroRNA-128 targets myostatin at coding domain sequence to regulate myoblasts in skeletal muscle development.

Science.gov (United States)

Shi, Lei; Zhou, Bo; Li, Pinghua; Schinckel, Allan P; Liang, Tingting; Wang, Han; Li, Huizhi; Fu, Lingling; Chu, Qingpo; Huang, Ruihua

2015-09-01

MicroRNAs (miRNAs or miRs) play a critical role in skeletal muscle development. In a previous study we observed that miR-128 was highly expressed in skeletal muscle. However, its function in regulating skeletal muscle development is not clear. Our hypothesis was that miR-128 is involved in the regulation of the proliferation and differentiation of skeletal myoblasts. In this study, through bioinformatics analyses, we demonstrate that miR-128 specifically targeted mRNA of myostatin (MSTN), a critical inhibitor of skeletal myogenesis, at coding domain sequence (CDS) region, resulting in down-regulating of myostatin post-transcription. Overexpression of miR-128 inhibited proliferation of mouse C2C12 myoblast cells but promoted myotube formation; whereas knockdown of miR-128 had completely opposite effects. In addition, ectopic miR-128 regulated the expression of myogenic factor 5 (Myf5), myogenin (MyoG), paired box (Pax) 3 and 7. Furthermore, an inverse relationship was found between the expression of miR-128 and MSTN protein expression in vivo and in vitro. Taken together, these results reveal that there is a novel pathway in skeletal muscle development in which miR-128 regulates myostatin at CDS region to inhibit proliferation but promote differentiation of myoblast cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Possible role of TIEG1 as a feedback regulator of myostatin and TGF-β in myoblasts

International Nuclear Information System (INIS)

Miyake, Masato; Hayashi, Shinichiro; Iwasaki, Shunsuke; Chao, Guozheng; Takahashi, Hideyuki; Watanabe, Kouichi; Ohwada, Shyuichi; Aso, Hisashi; Yamaguchi, Takahiro

2010-01-01

Myostatin and TGF-β negatively regulate skeletal muscle development and growth. Both factors signal through the Smad2/3 pathway. However, the regulatory mechanism of myostatin and TGF-β signaling remains unclear. TGF-β inducible early gene (TIEG) 1 is highly expressed in skeletal muscle and has been implicated in the modulation of TGF-β signaling. These findings prompted us to investigate the effect of TIEG1 on myostatin and TGF-β signaling using C2C12 myoblasts. Myostatin and TGF-β induced the expression of TIEG1 and Smad7 mRNAs, but not TIEG2 mRNA, in proliferating C2C12 cells. When differentiating C2C12 myoblasts were stimulated by myostatin, TIEG1 mRNA was up-regulated at a late stage of differentiation. In contrast, TGF-β enhanced TIEG1 expression at an early stage. Overexpression of TIEG1 prevented the transcriptional activation of Smad by myostatin and TGF-β in both proliferating or differentiating C2C12 cells, but the expression of Smad2 and Smad7 mRNAs was not affected. Forced expression of TIEG1 inhibited myogenic differentiation but did not cause more inhibition than the empty vector in the presence of myostatin or TGF-β. These results demonstrate that TIEG1 is one possible feedback regulator of myostatin and TGF-β that prevents excess action in myoblasts.

Improvement of maternal vitamin D status with 25-hydroxycholecalciferol positively impacts porcine fetal skeletal muscle development and myoblast activity.

Science.gov (United States)

Hines, E A; Coffey, J D; Starkey, C W; Chung, T K; Starkey, J D

2013-09-01

There is little information available regarding the influence of maternal vitamin D status on fetal skeletal muscle development. Therefore, we investigated the effect of improved vitamin D status resulting from 25-hydroxycholecalciferol (25OHD3) supplementation of dams on fetal skeletal muscle developmental characteristics and myoblast activity using Camborough 22 gilts (n = 40) randomly assigned to 1 of 2 corn-soybean meal-based diets. The control diet (CTL) contained 2,500 IU cholecalciferol (D3)/kg diet, whereas the experimental diet contained 500 IU D3/kg diet plus 50 µg 25OHD3/kg diet. Gilts were fed 2.7 kg of their assigned diet once daily beginning 43 d before breeding through d 90 of gestation. On gestational d 90 (± 1), fetal LM and semitendinosus muscle samples were collected for analysis of developmental characteristics and myoblast activity, respectively. No treatment difference was observed in fetal LM cross-sectional area (P = 0.25). Fetuses from 25OHD3-supplemented gilts had more LM fibers (P = 0.04) that tended to be smaller in cross-sectional area compared with CTL fetuses (P = 0.11). A numerical increase in the total number of Pax7+ myoblasts was also observed in fetuses from 25OHD3-supplemented gilts (P = 0.12). Myoblasts derived from the muscles of fetuses from 25OHD3-fed dams displayed an extended proliferative phase in culture compared with those from fetuses of dams fed only D3 (P importance of maternal vitamin D status on the development of fetal skeletal muscle.

Ionizing radiation increases primary cilia incidence and induces multiciliation in C2C12 myoblasts

Czech Academy of Sciences Publication Activity Database

Filipová, A.; Diaz-Garcia, D.; Bezrouk, A.; Čížková, D.; Havelek, R.; Vávrová, J.; Dayanithi, Govindan; Řezáčová, M.

2015-01-01

Roč. 39, č. 8 (2015), s. 943-953 ISSN 1065-6995 Institutional support: RVO:68378041 Keywords : cell line * ionizing radiation * multiple cilia * myoblast * primary cilium * serum starvation stress Subject RIV: FP - Other Medical Disciplines Impact factor: 1.663, year: 2015

Differentiation-Associated Downregulation of Poly(ADP-Ribose Polymerase-1 Expression in Myoblasts Serves to Increase Their Resistance to Oxidative Stress.

Directory of Open Access Journals (Sweden)

Gábor Oláh

Full Text Available Poly(ADP-ribose polymerase 1 (PARP-1, the major isoform of the poly (ADP-ribose polymerase family, is a constitutive nuclear and mitochondrial protein with well-recognized roles in various essential cellular functions such as DNA repair, signal transduction, apoptosis, as well as in a variety of pathophysiological conditions including sepsis, diabetes and cancer. Activation of PARP-1 in response to oxidative stress catalyzes the covalent attachment of the poly (ADP-ribose (PAR groups on itself and other acceptor proteins, utilizing NAD+ as a substrate. Overactivation of PARP-1 depletes intracellular NAD+ influencing mitochondrial electron transport, cellular ATP generation and, if persistent, can result in necrotic cell death. Due to their high metabolic activity, skeletal muscle cells are particularly exposed to constant oxidative stress insults. In this study, we investigated the role of PARP-1 in a well-defined model of murine skeletal muscle differentiation (C2C12 and compare the responses to oxidative stress of undifferentiated myoblasts and differentiated myotubes. We observed a marked reduction of PARP-1 expression as myoblasts differentiated into myotubes. This alteration correlated with an increased resistance to oxidative stress of the myotubes, as measured by MTT and LDH assays. Mitochondrial function, assessed by measuring mitochondrial membrane potential, was preserved under oxidative stress in myotubes compared to myoblasts. Moreover, basal respiration, ATP synthesis, and the maximal respiratory capacity of mitochondria were higher in myotubes than in myoblasts. Inhibition of the catalytic activity of PARP-1 by PJ34 (a phenanthridinone PARP inhibitor exerted greater protective effects in undifferentiated myoblasts than in differentiated myotubes. The above observations in C2C12 cells were also confirmed in a rat-derived skeletal muscle cell line (L6. Forced overexpression of PARP1 in C2C12 myotubes sensitized the cells to oxidant

The Use of Platelet-Rich and Platelet-Poor Plasma to Enhance Differentiation of Skeletal Myoblasts: Implications for the Use of Autologous Blood Products for Muscle Regeneration.

Science.gov (United States)

Miroshnychenko, Olga; Chang, Wen-Teh; Dragoo, Jason L

2017-03-01

Platelet-rich plasma (PRP) has been used to augment tissue repair and regeneration after musculoskeletal injury. However, there is increasing clinical evidence that PRP does not show a consistent clinical effect. Purpose/Hypothesis: This study aimed to compare the effects of the following non-neutrophil-containing (leukocyte-poor) plasma fractions on human skeletal muscle myoblast (HSMM) differentiation: (1) PRP, (2) modified PRP (Mod-PRP), in which transforming growth factor β1 (TGF-β1) and myostatin (MSTN) were depleted, and (3) platelet-poor plasma (PPP). The hypothesis was that leukocyte-poor PRP would lead to myoblast proliferation (not differentiation), whereas certain modifications of PRP preparations would increase myoblast differentiation, which is necessary for skeletal muscle regeneration. Controlled laboratory study. Blood from 7 human donors was individually processed to simultaneously create leukocyte-poor fractions: PRP, Mod-PRP, PPP, and secondarily spun PRP and Mod-PRP (PRP ss and Mod-PRP ss , respectively). Mod-PRP was produced by removing TGF-β1 and MSTN from PRP using antibodies attached to sterile beads, while a second-stage centrifugal spin of PRP was performed to remove platelets. The biologics were individually added to cell culture groups. Analysis for induction into myoblast differentiation pathways included Western blot analysis, reverse-transcription polymerase chain reaction, and immunohistochemistry, as well as confocal microscopy to assess polynucleated myotubule formation. HSMMs cultured with PRP showed an increase in proliferation but no evidence of differentiation. Western blot analysis confirmed that MSTN and TGF-β1 could be decreased in Mod-PRP using antibody-coated beads, but this modification mildly improved myoblast differentiation. However, cell culture with PPP, PRP ss , and Mod-PRP ss led to a decreased proliferation rate but a significant induction of myoblast differentiation verified by increased multinucleated

pPKCδ activates SC35 splicing factor during H9c2 myoblastic differentiation.

Science.gov (United States)

Zara, Susi; Falconi, Mirella; Rapino, Monica; Zago, Michela; Orsini, Giovanna; Mazzotti, Giovanni; Cataldi, Amelia; Teti, Gabriella

2011-01-01

Although Protein Kinase C (PKC) isoforms' role in the neonatal and adult cardiac tissue development and ageing has been widely described "in vivo", the interaction of such enzymes with specific nuclear substrates needs to be investigated. The aim of our research has been the study of the expression, localization and interaction with the splicing factor SC35 of PKC isoforms (α, δ, ε, ζ) and their potential role in modulating the transcription machinery. H9c2 cells induced to myoblast differentiation in the presence of 1% Horse Serum (HS) have represented our experimental model. The expression of PKC isoforms, their distribution and interaction with SC35 have been evaluated by western blotting, co-immunoprecipitation and double gold immunolabeling for transmission and scanning electron microscopy. Our results show PKCδ as the most expressed isoform in differentiated cells. Surprisingly, the distribution of PKCδ and SC35 does not show any significant modification between 10%FBS and 1%HS treated samples and no co-localization is observed. Moreover the interaction between the phosphorylated form of PKCδ (pPKCδ) and SC35 increases, is distributed and co-localizes within the nucleus of differentiated H9c2. These data represent reasonable evidence of pPKCδ mediated SC35 splicing factor activation, suggesting its direct effect on transcription via interaction with the transcription machinery. Furthermore, this co-localization represents a crucial event resulting in downstream changes in transcription of components which determine the morphological modifications related to cardiomyoblast differentiated phenotype.

L6E9 Myoblasts Are Deficient of Myostatin and Additional TGF- Members Are Candidates to Developmentally Control Their Fiber Formation

Directory of Open Access Journals (Sweden)

Stefania Rossi

2010-01-01

Full Text Available This work provides evidence that the robust myoblast differentiation observed in L6E9 cells is causally linked to deficiency of myostatin, which, conversely, has been found to be expressed in C2C12 cells. However, despite the absence of endogenous myostatin, L6E9 myoblasts expressed functional Activin receptors type II (ActRIIs and follistatin as well as the highly related TGF- members Activins and GDF11, suggesting that in this cell line the regulation of fiber size might be under the control of multiple regulators regardless of myostatin. In line with this hypothesis, delivery of a dominant-negative ActRIIb form or the increase of follistatin, as obtained via Trichostatin treatment or stable transfection of a short human follistatin form, enhanced the L6E9 cell differentiation and further increased the size of myotubes, suggesting that L6E9 myoblasts provide a spontaneous myostatin knock-out in vitro model to study TGF- ligands involved in developmental regulation of fiber size.

Myoblast sensitivity and fibroblast insensitivity to osteogenic conversion by BMP-2 correlates with the expression of Bmpr-1a

Directory of Open Access Journals (Sweden)

North Kathryn N

2009-05-01

Full Text Available Abstract Background Osteoblasts are considered to primarily arise from osseous progenitors within the periosteum or bone marrow. We have speculated that cells from local soft tissues may also take on an osteogenic phenotype. Myoblasts are known to adopt a bone gene program upon treatment with the osteogenic bone morphogenetic proteins (BMP-2,-4,-6,-7,-9, but their osteogenic capacity relative to other progenitor types is unclear. We further hypothesized that the sensitivity of cells to BMP-2 would correlate with BMP receptor expression. Methods We directly compared the BMP-2 sensitivity of myoblastic murine cell lines and primary cells with osteoprogenitors from osseous tissues and fibroblasts. Fibroblasts forced to undergo myogenic conversion by transduction with a MyoD-expressing lentiviral vector (LV-MyoD were also examined. Outcome measures included alkaline phosphatase expression, matrix mineralization, and expression of osteogenic genes (alkaline phosphatase, osteocalcin and bone morphogenetic protein receptor-1A as measured by quantitative PCR. Results BMP-2 induced a rapid and robust osteogenic response in myoblasts and osteoprogenitors, but not in fibroblasts. Myoblasts and osteoprogenitors grown in osteogenic media rapidly upregulated Bmpr-1a expression. Chronic BMP-2 treatment resulted in peak Bmpr-1a expression at day 6 before declining, suggestive of a negative feedback mechanism. In contrast, fibroblasts expressed low levels of Bmpr-1a that was only weakly up-regulated by BMP-2 treatment. Bioinformatics analysis confirmed the presence of myogenic responsive elements in the proximal promoter region of human and murine BMPR-1A/Bmpr-1a. Forced myogenic gene expression in fibroblasts was associated with a significant increase in Bmpr-1a expression and a synergistic increase in the osteogenic response to BMP-2. Conclusion These data demonstrate the osteogenic sensitivity of muscle progenitors and provide a mechanistic insight into the

Heavy ion irradiation induces autophagy in irradiated C2C12 myoblasts and their bystander cells

International Nuclear Information System (INIS)

Hino, Mizuki; Tajika, Yuki; Hamada, Nobuyuki

2010-01-01

Autophagy is one of the major processes involved in the degradation of intracellular materials. Here, we examined the potential impact of heavy ion irradiation on the induction of autophagy in irradiated C2C12 mouse myoblasts and their non-targeted bystander cells. In irradiated cells, ultrastructural analysis revealed the accumulation of autophagic structures at various stages of autophagy (id est (i.e.) phagophores, autophagosomes and autolysosomes) within 20 min after irradiation. Multivesicular bodies (MVBs) and autolysosomes containing MVBs (amphisomes) were also observed. Heavy ion irradiation increased the staining of microtubule-associated protein 1 light chain 3 and LysoTracker Red (LTR). Such enhanced staining was suppressed by an autophagy inhibitor 3-methyladenine. In addition to irradiated cells, bystander cells were also positive with LTR staining. Altogether, these results suggest that heavy ion irradiation induces autophagy not only in irradiated myoblasts but also in their bystander cells. (author)

Complex interactions between human myoblasts and the surrounding 3D fibrin-based matrix.

Directory of Open Access Journals (Sweden)

Stéphane Chiron

Full Text Available Anchorage of muscle cells to the extracellular matrix is crucial for a range of fundamental biological processes including migration, survival and differentiation. Three-dimensional (3D culture has been proposed to provide a more physiological in vitro model of muscle growth and differentiation than routine 2D cultures. However, muscle cell adhesion and cell-matrix interplay of engineered muscle tissue remain to be determined. We have characterized cell-matrix interactions in 3D muscle culture and analyzed their consequences on cell differentiation. Human myoblasts were embedded in a fibrin matrix cast between two posts, cultured until confluence, and then induced to differentiate. Myoblasts in 3D aligned along the longitudinal axis of the gel. They displayed actin stress fibers evenly distributed around the nucleus and a cortical mesh of thin actin filaments. Adhesion sites in 3D were smaller in size than in rigid 2D culture but expression of adhesion site proteins, including α5 integrin and vinculin, was higher in 3D compared with 2D (p<0.05. Myoblasts and myotubes in 3D exhibited thicker and ellipsoid nuclei instead of the thin disk-like shape of the nuclei in 2D (p<0.001. Differentiation kinetics were faster in 3D as demonstrated by higher mRNA concentrations of α-actinin and myosin. More important, the elastic modulus of engineered muscle tissues increased significantly from 3.5 ± 0.8 to 7.4 ± 4.7 kPa during proliferation (p<0.05 and reached 12.2 ± 6.0 kPa during differentiation (p<0.05, thus attesting the increase of matrix stiffness during proliferation and differentiation of the myocytes. In conclusion, we reported modulations of the adhesion complexes, the actin cytoskeleton and nuclear shape in 3D compared with routine 2D muscle culture. These findings point to complex interactions between muscle cells and the surrounding matrix with dynamic regulation of the cell-matrix stiffness.

Let-7b Regulates Myoblast Proliferation by Inhibiting IGF2BP3 Expression in Dwarf and Normal Chicken

Science.gov (United States)

Lin, Shumao; Luo, Wen; Ye, Yaqiong; Bekele, Endashaw J.; Nie, Qinghua; Li, Yugu; Zhang, Xiquan

2017-01-01

The sex-linked dwarf chicken is caused by the mutation of growth hormone receptor (GHR) gene and characterized by shorter shanks, lower body weight, smaller muscle fiber diameter and fewer muscle fiber number. However, the precise regulatory pathways that lead to the inhibition of skeletal muscle growth in dwarf chickens still remain unclear. Here we found a let-7b mediated pathway might play important role in the regulation of dwarf chicken skeletal muscle growth. Let-7b has higher expression in the skeletal muscle of dwarf chicken than in normal chicken, and the expression of insulin-like growth factor 2 mRNA binding protein 3 (IGF2BP3), which is a translational activator of IGF2, showed opposite expression trend to let-7b. In vitro cellular assays validated that let-7b directly inhibits IGF2BP3 expression through binding to its 3′UTR region, and the protein level but not mRNA level of IGF2 would be reduced in let-7b overexpressed chicken myoblast. Let-7b can inhibit cell proliferation and induce cell cycle arrest in chicken myoblast through let-7b-IGF2BP3-IGF2 signaling pathway. Additionally, let-7b can also regulate skeletal muscle growth through let-7b-GHR-GHR downstream genes pathway, but this pathway is non-existent in dwarf chicken because of the deletion mutation of GHR 3′UTR. Notably, as the loss binding site of GHR for let-7b, let-7b has enhanced its binding and inhibition on IGF2BP3 in dwarf myoblast, suggesting that the miRNA can balance its inhibiting effect through dynamic regulate its binding to target genes. Collectively, these results not only indicate that let-7b can inhibit skeletal muscle growth through let-7b-IGF2BP3-IGF2 signaling pathway, but also show that let-7b regulates myoblast proliferation by inhibiting IGF2BP3 expression in dwarf and normal chickens. PMID:28736533

The cAMP Response Element Binding protein (CREB) is activated by Insulin-like Growth Factor-1 (IGF-1) and regulates myostatin gene expression in skeletal myoblast

International Nuclear Information System (INIS)

Zuloaga, R.; Fuentes, E.N.; Molina, A.; Valdés, J.A.

2013-01-01

Highlights: •IGF-1 induces the activation of CREB via IGF-1R/PI3K/PLC signaling pathway. •Calcium dependent signaling pathways regulate myostatin gene expression. •IGF-1 regulates myostatin gene expression via CREB transcription in skeletal myoblast. -- Abstract: Myostatin, a member of the Transforming Growth Factor beta (TGF-β) superfamily, plays an important role as a negative regulator of skeletal muscle growth and differentiation. We have previously reported that IGF-1 induces a transient myostatin mRNA expression, through the activation of the Nuclear Factor of Activated T cells (NFAT) in an IP 3 /calcium-dependent manner. Here we examined the activation of CREB transcription factor as downstream targets of IGF-1 during myoblast differentiation and its role as a regulator of myostatin gene expression. In cultured skeletal myoblast, IGF-1 induced the phosphorylation and transcriptional activation of CREB via IGF-1 Receptor/Phosphatidylinositol 3-Kinase (PI3K)/Phospholipase C gamma (PLC γ), signaling pathways. Also, IGF-1 induced calcium-dependent molecules such as Calmodulin Kinase II (CaMK II), Extracellular signal-regulated Kinases (ERK), Protein Kinase C (PKC). Additionally, we examined myostatin mRNA levels and myostatin promoter activity in differentiated myoblasts stimulated with IGF-1. We found a significant increase in mRNA contents of myostatin and its reporter activity after treatment with IGF-1. The expression of myostatin in differentiated myoblast was downregulated by the transfection of siRNA–CREB and by pharmacological inhibitors of the signaling pathways involved in CREB activation. By using pharmacological and genetic approaches together these data demonstrate that IGF-1 regulates the myostatin gene expression via CREB transcription factor during muscle cell differentiation

The cAMP Response Element Binding protein (CREB) is activated by Insulin-like Growth Factor-1 (IGF-1) and regulates myostatin gene expression in skeletal myoblast

Energy Technology Data Exchange (ETDEWEB)

Zuloaga, R. [Facultad de Ciencias Biológicas, Universidad Andres Bello, Santiago (Chile); Fuentes, E.N.; Molina, A. [Facultad de Ciencias Biológicas, Universidad Andres Bello, Santiago (Chile); Interdisciplinary Center for Aquaculture Research (INCAR), Víctor Lamas 1290, PO Box 160-C, Concepción (Chile); Valdés, J.A., E-mail: jvaldes@unab.cl [Facultad de Ciencias Biológicas, Universidad Andres Bello, Santiago (Chile); Interdisciplinary Center for Aquaculture Research (INCAR), Víctor Lamas 1290, PO Box 160-C, Concepción (Chile)

2013-10-18

Highlights: •IGF-1 induces the activation of CREB via IGF-1R/PI3K/PLC signaling pathway. •Calcium dependent signaling pathways regulate myostatin gene expression. •IGF-1 regulates myostatin gene expression via CREB transcription in skeletal myoblast. -- Abstract: Myostatin, a member of the Transforming Growth Factor beta (TGF-β) superfamily, plays an important role as a negative regulator of skeletal muscle growth and differentiation. We have previously reported that IGF-1 induces a transient myostatin mRNA expression, through the activation of the Nuclear Factor of Activated T cells (NFAT) in an IP{sub 3}/calcium-dependent manner. Here we examined the activation of CREB transcription factor as downstream targets of IGF-1 during myoblast differentiation and its role as a regulator of myostatin gene expression. In cultured skeletal myoblast, IGF-1 induced the phosphorylation and transcriptional activation of CREB via IGF-1 Receptor/Phosphatidylinositol 3-Kinase (PI3K)/Phospholipase C gamma (PLC γ), signaling pathways. Also, IGF-1 induced calcium-dependent molecules such as Calmodulin Kinase II (CaMK II), Extracellular signal-regulated Kinases (ERK), Protein Kinase C (PKC). Additionally, we examined myostatin mRNA levels and myostatin promoter activity in differentiated myoblasts stimulated with IGF-1. We found a significant increase in mRNA contents of myostatin and its reporter activity after treatment with IGF-1. The expression of myostatin in differentiated myoblast was downregulated by the transfection of siRNA–CREB and by pharmacological inhibitors of the signaling pathways involved in CREB activation. By using pharmacological and genetic approaches together these data demonstrate that IGF-1 regulates the myostatin gene expression via CREB transcription factor during muscle cell differentiation.

Inhibition of galectin-3 ameliorates the consequences of cardiac lipotoxicity in a rat model of diet-induced obesity

Directory of Open Access Journals (Sweden)

Gema Marín-Royo

2018-02-01

Full Text Available Obesity is accompanied by metabolic alterations characterized by insulin resistance and cardiac lipotoxicity. Galectin-3 (Gal-3 induces cardiac inflammation and fibrosis in the context of obesity; however, its role in the metabolic consequences of obesity is not totally established. We have investigated the potential role of Gal-3 in the cardiac metabolic disturbances associated with obesity. In addition, we have explored whether this participation is, at least partially, acting on mitochondrial damage. Gal-3 inhibition in rats that were fed a high-fat diet (HFD for 6 weeks with modified citrus pectin (MCP; 100 mg/kg/day attenuated the increase in cardiac levels of total triglyceride (TG. MCP treatment also prevented the increase in cardiac protein levels of carnitine palmitoyl transferase IA, mitofusin 1, and mitochondrial complexes I and II, reactive oxygen species accumulation and decrease in those of complex V but did not affect the reduction in 18F-fluorodeoxyglucose uptake observed in HFD rats. The exposure of cardiac myoblasts (H9c2 to palmitic acid increased the rate of respiration, mainly due to an increase in the proton leak, glycolysis, oxidative stress, β-oxidation and reduced mitochondrial membrane potential. Inhibition of Gal-3 activity was unable to affect these changes. Our findings indicate that Gal-3 inhibition attenuates some of the consequences of cardiac lipotoxicity induced by a HFD since it reduced TG and lysophosphatidyl choline (LPC levels. These reductions were accompanied by amelioration of the mitochondrial damage observed in HFD rats, although no improvement was observed regarding insulin resistance. These findings increase the interest for Gal-3 as a potential new target for therapeutic intervention to prevent obesity-associated cardiac lipotoxicity and subsequent mitochondrial dysfunction.

Three-Dimensional Elastomeric Scaffolds Designed with Cardiac-Mimetic Structural and Mechanical Features

Science.gov (United States)

Neal, Rebekah A.; Jean, Aurélie; Park, Hyoungshin; Wu, Patrick B.; Hsiao, James; Engelmayr, George C.; Langer, Robert

2013-01-01

Tissue-engineered constructs, at the interface of material science, biology, engineering, and medicine, have the capacity to improve outcomes for cardiac patients by providing living cells and degradable biomaterials that can regenerate the native myocardium. With an ultimate goal of both delivering cells and providing mechanical support to the healing heart, we designed three-dimensional (3D) elastomeric scaffolds with (1) stiffnesses and anisotropy mimicking explanted myocardial specimens as predicted by finite-element (FE) modeling, (2) systematically varied combinations of rectangular pore pattern, pore aspect ratio, and strut width, and (3) structural features approaching tissue scale. Based on predicted mechanical properties, three scaffold designs were selected from eight candidates for fabrication from poly(glycerol sebacate) by micromolding from silicon wafers. Large 20×20 mm scaffolds with high aspect ratio features (5:1 strut height:strut width) were reproducibly cast, cured, and demolded at a relatively high throughput. Empirically measured mechanical properties demonstrated that scaffolds were cardiac mimetic and validated FE model predictions. Two-layered scaffolds providing fully interconnected pore networks were fabricated by layer-by-layer assembly. C2C12 myoblasts cultured on one-layered scaffolds exhibited specific patterns of cell elongation and interconnectivity that appeared to be guided by the scaffold pore pattern. Neonatal rat heart cells cultured on two-layered scaffolds for 1 week were contractile, both spontaneously and in response to electrical stimulation, and expressed sarcomeric α-actinin, a cardiac biomarker. This work not only demonstrated several scaffold designs that promoted functional assembly of rat heart cells, but also provided the foundation for further computational and empirical investigations of 3D elastomeric scaffolds for cardiac tissue engineering. PMID:23190320

Myosin heavy chain-like localizes at cell contact sites during Drosophila myoblast fusion and interacts in vitro with Rolling pebbles 7

Energy Technology Data Exchange (ETDEWEB)

Bonn, Bettina R.; Rudolf, Anja; Hornbruch-Freitag, Christina; Daum, Gabor; Kuckwa, Jessica; Kastl, Lena; Buttgereit, Detlev [Developmental Biology, Department of Biology, Philipps-Universität Marburg, Karl-von-Frisch-Strasse 8, 35037 Marburg (Germany); Renkawitz-Pohl, Renate, E-mail: renkawit@biologie.uni-marburg.de [Developmental Biology, Department of Biology, Philipps-Universität Marburg, Karl-von-Frisch-Strasse 8, 35037 Marburg (Germany)

2013-02-15

Besides representing the sarcomeric thick filaments, myosins are involved in many cellular transport and motility processes. Myosin heavy chains are grouped into 18 classes. Here we show that in Drosophila, the unconventional group XVIII myosin heavy chain-like (Mhcl) is transcribed in the mesoderm of embryos, most prominently in founder cells (FCs). An ectopically expressed GFP-tagged Mhcl localizes in the growing muscle at cell–cell contacts towards the attached fusion competent myoblast (FCM). We further show that Mhcl interacts in vitro with the essential fusion protein Rolling pebbles 7 (Rols7), which is part of a protein complex established at cell contact sites (Fusion-restricted Myogenic-Adhesive Structure or FuRMAS). Here, branched F-actin is likely needed to widen the fusion pore and to integrate the myoblast into the growing muscle. We show that the localization of Mhcl is dependent on the presence of Rols7, and we postulate that Mhcl acts at the FuRMAS as an actin motor protein. We further show that Mhcl deficient embryos develop a wild-type musculature. We thus propose that Mhcl functions redundantly to other myosin heavy chains in myoblasts. Lastly, we found that the protein is detectable adjacent to the sarcomeric Z-discs, suggesting an additional function in mature muscles. - Highlights: ► The class XVIII myosin encoding gene Mhcl is transcribed in the mesoderm. ► Mhcl localization at contact sites of fusing myoblasts depends on Rols7. ► Mhcl interacts in vitro with Rols7 which is essential for myogenesis. ► Functional redundancy with other myosins is likely as mutants show no muscle defects. ► Mhcl localizes adjacent to Z-discs of sarcomeres and might support muscle integrity.

Myosin heavy chain-like localizes at cell contact sites during Drosophila myoblast fusion and interacts in vitro with Rolling pebbles 7

International Nuclear Information System (INIS)

Bonn, Bettina R.; Rudolf, Anja; Hornbruch-Freitag, Christina; Daum, Gabor; Kuckwa, Jessica; Kastl, Lena; Buttgereit, Detlev; Renkawitz-Pohl, Renate

2013-01-01

Besides representing the sarcomeric thick filaments, myosins are involved in many cellular transport and motility processes. Myosin heavy chains are grouped into 18 classes. Here we show that in Drosophila, the unconventional group XVIII myosin heavy chain-like (Mhcl) is transcribed in the mesoderm of embryos, most prominently in founder cells (FCs). An ectopically expressed GFP-tagged Mhcl localizes in the growing muscle at cell–cell contacts towards the attached fusion competent myoblast (FCM). We further show that Mhcl interacts in vitro with the essential fusion protein Rolling pebbles 7 (Rols7), which is part of a protein complex established at cell contact sites (Fusion-restricted Myogenic-Adhesive Structure or FuRMAS). Here, branched F-actin is likely needed to widen the fusion pore and to integrate the myoblast into the growing muscle. We show that the localization of Mhcl is dependent on the presence of Rols7, and we postulate that Mhcl acts at the FuRMAS as an actin motor protein. We further show that Mhcl deficient embryos develop a wild-type musculature. We thus propose that Mhcl functions redundantly to other myosin heavy chains in myoblasts. Lastly, we found that the protein is detectable adjacent to the sarcomeric Z-discs, suggesting an additional function in mature muscles. - Highlights: ► The class XVIII myosin encoding gene Mhcl is transcribed in the mesoderm. ► Mhcl localization at contact sites of fusing myoblasts depends on Rols7. ► Mhcl interacts in vitro with Rols7 which is essential for myogenesis. ► Functional redundancy with other myosins is likely as mutants show no muscle defects. ► Mhcl localizes adjacent to Z-discs of sarcomeres and might support muscle integrity

The CDM Superfamily Protein MBC Directs Myoblast Fusion through a Mechanism That Requires Phosphatidylinositol 3,4,5-Triphosphate Binding but Is Independent of Direct Interaction with DCrk▿§

Science.gov (United States)

Balagopalan, Lakshmi; Chen, Mei-Hui; Geisbrecht, Erika R.; Abmayr, Susan M.

2006-01-01

myoblast city (mbc), a member of the CDM superfamily, is essential in the Drosophila melanogaster embryo for fusion of myoblasts into multinucleate fibers. Using germ line clones in which both maternal and zygotic contributions were eliminated and rescue of the zygotic loss-of-function phenotype, we established that mbc is required in the fusion-competent subset of myoblasts. Along with its close orthologs Dock180 and CED-5, MBC has an SH3 domain at its N terminus, conserved internal domains termed DHR1 and DHR2 (or “Docker”), and C-terminal proline-rich domains that associate with the adapter protein DCrk. The importance of these domains has been evaluated by the ability of MBC mutations and deletions to rescue the mbc loss-of-function muscle phenotype. We demonstrate that the SH3 and Docker domains are essential. Moreover, ethyl methanesulfonate-induced mutations that change amino acids within the MBC Docker domain to residues that are conserved in other CDM family members nevertheless eliminate MBC function in the embryo, which suggests that these sites may mediate interactions specific to Drosophila MBC. A functional requirement for the conserved DHR1 domain, which binds to phosphatidylinositol 3,4,5-triphosphate, implicates phosphoinositide signaling in myoblast fusion. Finally, the proline-rich C-terminal sites mediate strong interactions with DCrk, as expected. These sites are not required for MBC to rescue the muscle loss-of-function phenotype, however, which suggests that MBC's role in myoblast fusion can be carried out independently of direct DCrk binding. PMID:17030600

DNA replication timing is maintained genome-wide in primary human myoblasts independent of D4Z4 contraction in FSH muscular dystrophy.

Directory of Open Access Journals (Sweden)

Benjamin D Pope

Full Text Available Facioscapulohumeral muscular dystrophy (FSHD is linked to contraction of an array of tandem 3.3-kb repeats (D4Z4 at 4q35.2 from 11-100 copies to 1-10 copies. The extent to which D4Z4 contraction at 4q35.2 affects overall 4q35.2 chromatin organization remains unclear. Because DNA replication timing is highly predictive of long-range chromatin interactions, we generated genome-wide replication-timing profiles for FSHD and control myogenic precursor cells. We compared non-immortalized myoblasts from four FSHD patients and three control individuals to each other and to a variety of other human cell types. This study also represents the first genome-wide comparison of replication timing profiles in non-immortalized human cell cultures. Myoblasts from both control and FSHD individuals all shared a myoblast-specific replication profile. In contrast, male and female individuals were readily distinguished by monoallelic differences in replication timing at DXZ4 and other regions across the X chromosome affected by X inactivation. We conclude that replication timing is a robust cell-type specific feature that is unaffected by FSHD-related D4Z4 contraction.

Low Oxygen Tension Enhances Expression of Myogenic Genes When Human Myoblasts Are Activated from G0 Arrest

DEFF Research Database (Denmark)

Sellathurai, Jeeva; Nielsen, Joachim; Hejbøl, Eva Kildall

2016-01-01

-PCR, immunocytochemistry and western blot. RESULTS AND CONCLUSIONS: We found an increase in proliferation rate of myoblasts when activated at a low oxygen tension (1% O2) compared to 21% O2. In addition, the gene expression studies showed up regulation of the myogenesis related genes PAX3, PAX7, MYOD, MYOG (myogenin), MET......, NCAM, DES (desmin), MEF2A, MEF2C and CDH15 (M-cadherin), however, the fraction of DES and MYOD positive cells was not increased by low oxygen tension, indicating that 1% O2 may not have a functional effect on the myogenic response. Furthermore, the expression of genes involved in the TGFβ, Notch...... and Wnt signaling pathways were also up regulated in low oxygen tension. The differences in gene expression were most pronounced at day one after activation from G0-arrest, thus the initial activation of myoblasts seemed most sensitive to changes in oxygen tension. Protein expression of HES1 and β...

A novel whole-cell lysate kinase assay identifies substrates of the p38 MAPK in differentiating myoblasts

Directory of Open Access Journals (Sweden)

Knight James DR

2012-03-01

Full Text Available Abstract Background The p38α mitogen-activated protein kinase (MAPK is a critical mediator of myoblast differentiation, and does so in part through the phosphorylation and regulation of several transcription factors and chromatin remodelling proteins. However, whether p38α is involved in processes other than gene regulation during myogenesis is currently unknown, and why other p38 isoforms cannot compensate for its loss is unclear. Methods To further characterise the involvement of p38α during myoblast differentiation, we developed and applied a simple technique for identifying relevant in vivo kinase substrates and their phosphorylation sites. In addition to identifying substrates for one kinase, the technique can be used in vitro to compare multiple kinases in the same experiment, and we made use of this to study the substrate specificities of the p38α and β isoforms. Results Applying the technique to p38α resulted in the identification of seven in vivo phosphorylation sites on six proteins, four of which are cytoplasmic, in lysate derived from differentiating myoblasts. An in vitro comparison with p38β revealed that substrate specificity does not discriminate these two isoforms, but rather that their distinguishing characteristic appears to be cellular localisation. Conclusion Our results suggest p38α has a novel cytoplasmic role during myogenesis and that its unique cellular localisation may be why p38β and other isoforms cannot compensate for its absence. The substrate-finding approach presented here also provides a necessary tool for studying the hundreds of protein kinases that exist and for uncovering the deeper mechanisms of phosphorylation-dependent cell signalling.

α-Syntrophin stabilizes catalase to reduce endogenous reactive oxygen species levels during myoblast differentiation.

Science.gov (United States)

Moon, Jae Yun; Choi, Su Jin; Heo, Cheol Ho; Kim, Hwan Myung; Kim, Hye Sun

2017-07-01

α-Syntrophin is a component of the dystrophin-glycoprotein complex that interacts with various intracellular signaling proteins in muscle cells. The α-syntrophin knock-down C2 cell line (SNKD), established by infecting lentivirus particles with α-syntrophin shRNA, is characterized by a defect in terminal differentiation and increase in cell death. Since myoblast differentiation is accompanied by intensive mitochondrial biogenesis, the generation of intracellular reactive oxygen species (ROS) is also increased during myogenesis. Two-photon microscopy imaging showed that excessive intracellular ROS accumulated during the differentiation of SNKD cells as compared with control cells. The formation of 4-hydroxynonenal adduct, a byproduct of lipid peroxidation during oxidative stress, significantly increased in differentiated SNKD myotubes and was dramatically reduced by epigallocatechin-3-gallate, a well-known ROS scavenger. Among antioxidant enzymes, catalase was significantly decreased during differentiation of SNKD cells without changes at the mRNA level. Of interest was the finding that the degradation of catalase was rescued by MG132, a proteasome inhibitor, in the SNKD cells. This study demonstrates a novel function of α-syntrophin. This protein plays an important role in the regulation of oxidative stress from endogenously generated ROS during myoblast differentiation by modulating the protein stability of catalase. © 2017 Federation of European Biochemical Societies.

Electroactive polyurethane/siloxane derived from castor oil as a versatile cardiac patch, part I: Synthesis, characterization, and myoblast proliferation and differentiation.

Science.gov (United States)

Baheiraei, Nafiseh; Gharibi, Reza; Yeganeh, Hamid; Miragoli, Michele; Salvarani, Nicolò; Di Pasquale, Elisa; Condorelli, Gianluigi

2016-03-01

Tissue-engineered cardiac patch aims at regenerating an infarcted heart by improving cardiac function and providing mechanical support to the diseased myocardium. In order to take advantages of electroactivity, a new synthetic method was developed for the introduction of an electroactive oligoaniline into the backbone of prepared patches. For this purpose, a series of electroactive polyurethane/siloxane films containing aniline tetramer (AT) was prepared through sol-gel reaction of trimethoxysilane functional intermediate polyurethane prepolymers made from castor oil and poly(ethylene glycol). Physicochemical, mechanical, and electrical conductivity of samples were evaluated and the recorded results were correlated to their structural characteristics. The optimized films were proved to be biodegradable and have tensile properties suitable for cardiac patch application. The embedded AT moieties in the backbone of the prepared samples preserved their electroactivity with the electrical conductivity in the range of 10 -4 S/cm. The prepared films were compatible with proliferation of C2C12 and had potential for enhancing myotube formation even without external electrical stimulation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 775-787, 2016. © 2015 Wiley Periodicals, Inc.

Use of 5-Bromodeoxyuridine and irradiation for the estimation of the myoblast and myocyte content of primary rat heart cell cultures

International Nuclear Information System (INIS)

Masse, M.J.O.; Harary, I.

1980-01-01

A method for killing dividing cells was adapted for the elimination of dividing heart muscle cells (myoblasts) in cultures. We have used this method to demonstrate their presence and to estimate their number as well as the number of nondividing heart muscle cells (myocytes) in the neo-natal rat heart. Cells were cultivated in BUdR (5-bromodeoxyuridine) 10 -4 M for 3 days and then irradiated with long uv light. The selective elimination of dividing cells led to a loss of myosin Ca 2+ -activated ATPase in the cultures. The percent of ATPase left after irradiation was 32% of the control in cultures derived from 1-day postnatal rats and 48% in cultures from 4-day postnatal rats. This reflects an in vivo shift of myoblasts to myocytes in the muscle cell population as the rat ages

Myogenesis in the sea urchin embryo: the molecular fingerprint of the myoblast precursors

Science.gov (United States)

2013-01-01

Background In sea urchin larvae the circumesophageal fibers form a prominent muscle system of mesodermal origin. Although the morphology and later development of this muscle system has been well-described, little is known about the molecular signature of these cells or their precise origin in the early embryo. As an invertebrate deuterostome that is more closely related to the vertebrates than other commonly used model systems in myogenesis, the sea urchin fills an important phylogenetic gap and provides a unique perspective on the evolution of muscle cell development. Results Here, we present a comprehensive description of the development of the sea urchin larval circumesophageal muscle lineage beginning with its mesodermal origin using high-resolution localization of the expression of several myogenic transcriptional regulators and differentiation genes. A few myoblasts are bilaterally distributed at the oral vegetal side of the tip of the archenteron and first appear at the late gastrula stage. The expression of the differentiation genes Myosin Heavy Chain, Tropomyosin I and II, as well as the regulatory genes MyoD2, FoxF, FoxC, FoxL1, Myocardin, Twist, and Tbx6 uniquely identify these cells. Interestingly, evolutionarily conserved myogenic factors such as Mef2, MyoR and Six1/2 are not expressed in sea urchin myoblasts but are found in other mesodermal domains of the tip of the archenteron. The regulatory states of these domains were characterized in detail. Moreover, using a combinatorial analysis of gene expression we followed the development of the FoxF/FoxC positive cells from the onset of expression to the end of gastrulation. Our data allowed us to build a complete map of the Non-Skeletogenic Mesoderm at the very early gastrula stage, in which specific molecular signatures identify the precursors of different cell types. Among them, a small group of cells within the FoxY domain, which also express FoxC and SoxE, have been identified as plausible myoblast

The MSX1 homeoprotein recruits G9a methyltransferase to repressed target genes in myoblast cells.

Directory of Open Access Journals (Sweden)

Jingqiang Wang

Full Text Available Although the significance of lysine modifications of core histones for regulating gene expression is widely appreciated, the mechanisms by which these modifications are incorporated at specific regulatory elements during cellular differentiation remains largely unknown. In our previous studies, we have shown that in developing myoblasts the Msx1 homeoprotein represses gene expression by influencing the modification status of chromatin at its target genes. We now show that genomic binding by Msx1 promotes enrichment of the H3K9me2 mark on repressed target genes via recruitment of G9a histone methyltransferase, the enzyme responsible for catalyzing this histone mark. Interaction of Msx1 with G9a is mediated via the homeodomain and is required for transcriptional repression and regulation of cellular differentiation, as well as enrichment of the H3K9me2 mark in proximity to Msx1 binding sites on repressed target genes in myoblast cells as well as the developing limb. We propose that regulation of chromatin status by Msx1 recruitment of G9a and other histone modifying enzymes to regulatory regions of target genes represents an important means of regulating the gene expression during development.

Skeletal muscle Kv7 (KCNQ) channels in myoblast differentiation and proliferation

International Nuclear Information System (INIS)

Roura-Ferrer, Meritxell; Sole, Laura; Martinez-Marmol, Ramon; Villalonga, Nuria; Felipe, Antonio

2008-01-01

Voltage-dependent K + channels (Kv) are involved in myocyte proliferation and differentiation by triggering changes in membrane potential and regulating cell volume. Since Kv7 channels may participate in these events, the purpose of this study was to investigate whether skeletal muscle Kv7.1 and Kv7.5 were involved during proliferation and myogenesis. Here we report that, while myotube formation did not regulate Kv7 channels, Kv7.5 was up-regulated during cell cycle progression. Although, Kv7.1 mRNA also increased during the G 1 -phase, pharmacological evidence mainly involves Kv7.5 in myoblast growth. Our results indicate that the cell cycle-dependent expression of Kv7.5 is involved in skeletal muscle cell proliferation

Mechanical stimuli activation of calpain is required for myoblast differentiation and occurs via an ERK/MAP kinase signaling pathway

DEFF Research Database (Denmark)

Grossi, Alberto; Karlsson, Anders H; Lawson, Moira Ann

2006-01-01

a magnetic bead stimulation assay and C2C12 mouse myoblasts cell population, we have shown that mechanical signals transmitted through the C2C12 cells interaction with laminin cause an increase in cellular differentiation. This signaling results in an increase in the number of myotubes formed in the cultures...

Anticancer activity of biologically synthesized silver and gold nanoparticles on mouse myoblast cancer cells and their toxicity against embryonic zebrafish

International Nuclear Information System (INIS)

Ramachandran, Rajan; Krishnaraj, Chandran; Sivakumar, Allur Subramaniyan; Prasannakumar, Palaniappan; Abhay Kumar, V.K.; Shim, Kwan Seob; Song, Chul-Gyu; Yun, Soon-Il

2017-01-01

The aim of this study was to evaluate the anticancer activity of bioinspired silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) against mouse myoblast cancer cells (C 2 C 12 ). Both AgNPs and AuNPs were biologically synthesized using Spinacia oleracea Linn., aqueous leaves extract. UV–Vis. spectrophotometer, high resolution-transmission electron microscopy (HR-TEM), field emission-scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) studies supported the successful synthesis of AgNPs and AuNPs. Both these NPs have shown cytotoxicity against C 2 C 12 cells even at very low concentration (5 μg/mL). Acridine orange/Ethidium bromide (AO/EB) dual staining confirmed the apoptotic morphological features. The levels of caspase enzymes (caspase-3 and caspase-7) were significantly up-regulated in NPs treated myoblast cells than the plant extract. Furthermore, in zebrafish embryo toxicity study, AgNPs showed 100% mortality at 3 μg/mL concentration while AuNPs exhibited the same at much higher concentration (300 mg/mL). Taken together, these results provide a preliminary guidance for the development of biomaterials based drugs to fight against the fatal diseases for example cancer. - Highlights: • Anticancer activity was done for the first time against mouse myoblast cells. • AgNPs showed 100% growth inhibition against C 2 C 12 cells at 20 μg/mL concentration. • AO/EB dual staining and caspase assays confirmed the apoptotic features. • Nanoparticles treated embryos showed yolk sac edema and tail malformation. • AgNPs were found to be more toxic to embryonic zebrafishes than the AuNPs.

Anticancer activity of biologically synthesized silver and gold nanoparticles on mouse myoblast cancer cells and their toxicity against embryonic zebrafish

Energy Technology Data Exchange (ETDEWEB)

Ramachandran, Rajan [Centre for Advanced Studies in Botany, School of Life Sciences, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu (India); Krishnaraj, Chandran [Department of Food Science & Technology, College of Agriculture & Life Sciences, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); M/s. Eureka Forbes Ltd, R & D Centre, Kudlu, Bangalore (India); Sivakumar, Allur Subramaniyan [Department of Animal Biotechnology, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Prasannakumar, Palaniappan [Advanced Biomedical Imaging Center, Department of Electronic Engineering, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Abhay Kumar, V.K. [M/s. Eureka Forbes Ltd, R & D Centre, Kudlu, Bangalore (India); Shim, Kwan Seob [Department of Animal Biotechnology, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Song, Chul-Gyu [Advanced Biomedical Imaging Center, Department of Electronic Engineering, Chonbuk National University, Jeonju 54896 (Korea, Republic of); Yun, Soon-Il, E-mail: siyun@jbnu.ac.kr [Department of Food Science & Technology, College of Agriculture & Life Sciences, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

2017-04-01

The aim of this study was to evaluate the anticancer activity of bioinspired silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs) against mouse myoblast cancer cells (C{sub 2}C{sub 12}). Both AgNPs and AuNPs were biologically synthesized using Spinacia oleracea Linn., aqueous leaves extract. UV–Vis. spectrophotometer, high resolution-transmission electron microscopy (HR-TEM), field emission-scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) studies supported the successful synthesis of AgNPs and AuNPs. Both these NPs have shown cytotoxicity against C{sub 2}C{sub 12} cells even at very low concentration (5 μg/mL). Acridine orange/Ethidium bromide (AO/EB) dual staining confirmed the apoptotic morphological features. The levels of caspase enzymes (caspase-3 and caspase-7) were significantly up-regulated in NPs treated myoblast cells than the plant extract. Furthermore, in zebrafish embryo toxicity study, AgNPs showed 100% mortality at 3 μg/mL concentration while AuNPs exhibited the same at much higher concentration (300 mg/mL). Taken together, these results provide a preliminary guidance for the development of biomaterials based drugs to fight against the fatal diseases for example cancer. - Highlights: • Anticancer activity was done for the first time against mouse myoblast cells. • AgNPs showed 100% growth inhibition against C{sub 2}C{sub 12} cells at 20 μg/mL concentration. • AO/EB dual staining and caspase assays confirmed the apoptotic features. • Nanoparticles treated embryos showed yolk sac edema and tail malformation. • AgNPs were found to be more toxic to embryonic zebrafishes than the AuNPs.

Creation of Dystrophin Expressing Chimeric Cells of Myoblast Origin as a Novel Stem Cell Based Therapy for Duchenne Muscular Dystrophy.

Science.gov (United States)

Siemionow, M; Cwykiel, J; Heydemann, A; Garcia-Martinez, J; Siemionow, K; Szilagyi, E

2018-04-01

Over the past decade different stem cell (SC) based approaches were tested to treat Duchenne Muscular Dystrophy (DMD), a lethal X-linked disorder caused by mutations in dystrophin gene. Despite research efforts, there is no curative therapy for DMD. Allogeneic SC therapies aim to restore dystrophin in the affected muscles; however, they are challenged by rejection and limited engraftment. Thus, there is a need to develop new more efficacious SC therapies. Chimeric Cells (CC), created via ex vivo fusion of donor and recipient cells, represent a promising therapeutic option for tissue regeneration and Vascularized Composite Allotransplantation (VCA) due to tolerogenic properties that eliminate the need for lifelong immunosuppression. This proof of concept study tested feasibility of myoblast fusion for Dystrophin Expressing. Chimeric Cell (DEC) therapy through in vitro characterization and in vivo assessment of engraftment, survival, and efficacy in the mdx mouse model of DMD. Murine DEC were created via ex vivo fusion of normal (snj) and dystrophin-deficient (mdx) myoblasts using polyethylene glycol. Efficacy of myoblast fusion was confirmed by flow cytometry and dystrophin immunostaining, while proliferative and myogenic differentiation capacity of DEC were assessed in vitro. Therapeutic effect after DEC transplant (0.5 × 10 6 ) into the gastrocnemius muscle (GM) of mdx mice was assessed by muscle functional tests. At 30 days post-transplant dystrophin expression in GM of injected mdx mice increased to 37.27 ± 12.1% and correlated with improvement of muscle strength and function. Our study confirmed feasibility and efficacy of DEC therapy and represents a novel SC based approach for treatment of muscular dystrophies.

A novel in vitro model for studying quiescence and activation of primary isolated human myoblasts

DEFF Research Database (Denmark)

Sellathurai, Jeeva; Cheedipudi, Sirisha; Dhawan, Jyotsna

2013-01-01

term exponentially proliferating cultures normally used for in vitro studies. Human myoblasts cultured through many passages inevitably consist of a mixture of proliferating and non-proliferating cells, while cells activated from G0 are in a synchronously proliferating phase, and therefore may...... be a better model for in vivo proliferating satellite cells. Furthermore, the temporal propagation of proliferation in these synchronized cultures resembles the pattern seen in vivo during regeneration. We therefore present this culture model as a useful and novel condition for molecular analysis...

High glucose-induced Ca2+ overload and oxidative stress contribute to apoptosis of cardiac cells through mitochondrial dependent and independent pathways.

Science.gov (United States)

Kumar, Sandeep; Kain, Vasundhara; Sitasawad, Sandhya L

2012-07-01

Cardiac cell apoptosis is the initiating factor of cardiac complications especially diabetic cardiomyopathy. Mitochondria are susceptible to the damaging effects of elevated glucose condition. Calcium overload and oxidative insult are the two mutually non-exclusive phenomena suggested to cause cardiac dysfunction. Here, we examined the effect of high-glucose induced calcium overload in calpain-1 mediated cardiac apoptosis in an in vitro setting. H9c2, rat ventricular myoblast cell line was treated with elevated glucose condition and the cellular consequences were studied. Intracellular calcium trafficking, ROS generation, calpain-1 activation and caspase-12 and caspase-9 pathway were studied using flow cytometry, confocal microscopy and Western blot analysis. High-glucose treatment resulted in increased intracellular calcium ([Ca2+]i) which was mobilized to the mitochondria. Concomitant intra-mitochondrial calcium ([Ca2+]m) increase resulted in enhanced reactive oxygen and nitrogen species generation. These events led to mitochondrial dysfunction and apoptosis. Cardiomyocyte death exhibited several classical markers of apoptosis, including activation of caspases, appearance of annexin V on the outer plasma membrane, increased population of cells with sub-G0/G1 DNA content and nuclear condensation. Key findings include elucidation of cell signaling mechanism of high-glucose induced calcium-dependent cysteine protease calpain-1 activation, which triggers non-conventional caspases as alternate mode of cell death. This information increases the understanding of cardiac cell death under hyperglycemic condition and can possibly be extended for designing new therapeutic strategies for diabetic cardiomyopathy. The novel findings of the study reveal that high glucose induces apoptosis by both mitochondria-dependent and independent pathways via concomitant rise in intracellular calcium. Copyright © 2012 Elsevier B.V. All rights reserved.

α-Syntrophin is involved in the survival signaling pathway in myoblasts under menadione-induced oxidative stress.

Science.gov (United States)

Lim, Jeong-A; Choi, Su Jin; Moon, Jae Yun; Kim, Hye Sun

2016-05-15

Dystrophin-deficient muscle is known to be more vulnerable to oxidative stress, but not much is known about the signaling pathway(s) responsible for this phenomenon. α-Syntrophin, a component of the dystrophin-glycoprotein complex, can function as a scaffold protein because of its multiple protein interaction domains. In this study, we investigated the role of α-syntrophin in C2 myoblasts under menadione-induced oxidative stress. We found that the protein level of α-syntrophin was elevated when cells were exposed to menadione. To investigate the function of α-syntrophin during oxidative stress, we established α-syntrophin-overexpressing and knockdown cell lines. The α-syntrophin-overexpressing cells were resistant to the menadione-induced oxidative stress. In addition, survival signalings such as protein kinase B (Akt) phosphorylation and the Bcl-2/BAX ratio were increased in these cells. On the other hand, apoptotic signals such as cleavage of caspase-3 and poly ADP ribose polymerase (PARP) were increased in the α-syntrophin knockdown cells. Furthermore, Ca(2+)influx, which is known to increase when cells are exposed to oxidative stress, decreased in the α-syntrophin-overexpressing cells, but increased in the knockdown cells. These results suggest that α-syntrophin plays a pivotal role in the survival pathway triggered by menadione-induced oxidative stress in cultured myoblasts. Copyright © 2016 Elsevier Inc. All rights reserved.

Action of lovastatin, simvastatin, and pravastatin on sterol synthesis and their antiproliferative effect in cultured myoblasts from human striated muscle

NARCIS (Netherlands)

Vliet, A.K. van; Nègre-Arrariou, P.; Thiel, G.C.F. van; Bolhuis, P.A.; Cohen, L.H.

1996-01-01

Lovastatin, simvastatin, and pravastatin are fairly strong inhibitors of sterol synthesis in human myoblasts in culture. Lovastatin and simvastatin have IC50 values of 19 ± 6 nM and 4.0 ± 2.3 nM, respectively. Pravastatin is a weaker inhibitor of sterol synthesis (IC50 value of 110 ± 38 nM). Through

NEU3 sialidase strictly modulates GM3 levels in skeletal myoblasts C2C12 thus favoring their differentiation and protecting them from apoptosis.

Science.gov (United States)

Anastasia, Luigi; Papini, Nadia; Colazzo, Francesca; Palazzolo, Giacomo; Tringali, Cristina; Dileo, Loredana; Piccoli, Marco; Conforti, Erika; Sitzia, Clementina; Monti, Eugenio; Sampaolesi, Maurilio; Tettamanti, Guido; Venerando, Bruno

2008-12-26

Membrane-bound sialidase NEU3, often referred to as the "ganglioside sialidase," has a critical regulatory function on the sialoglycosphingolipid pattern of the cell membrane, with an anti-apoptotic function, especially in cancer cells. Although other sialidases have been shown to be involved in skeletal muscle differentiation, the role of NEU3 had yet to be disclosed. Herein we report that NEU3 plays a key role in skeletal muscle differentiation by strictly modulating the ganglioside content of adjacent cells, with special regard to GM3. Induced down-regulation of NEU3 in murine C2C12 myoblasts, even when partial, totally inhibits their capability to differentiate by increasing the GM3 level above a critical point, which causes epidermal growth factor receptor inhibition (and ultimately its down-regulation) and an higher responsiveness of myoblasts to the apoptotic stimuli.

Modulation of Protein Quality Control and Proteasome to Autophagy Switch in Immortalized Myoblasts from Duchenne Muscular Dystrophy Patients

Directory of Open Access Journals (Sweden)

Marion Wattin

2018-01-01

Full Text Available The maintenance of proteome integrity is of primary importance in post-mitotic tissues such as muscle cells; thus, protein quality control mechanisms must be carefully regulated to ensure their optimal efficiency, a failure of these processes being associated with various muscular disorders. Duchenne muscular dystrophy (DMD is one of the most common and severe forms of muscular dystrophies and is caused by mutations in the dystrophin gene. Protein quality control modulations have been diversely observed in degenerating muscles of patients suffering from DMD or in animal models of the disease. In this study, we investigated whether modulations of protein quality control mechanisms already pre-exist in undifferentiated myoblasts originating from DMD patients. We report for the first time that the absence of dystrophin in human myoblasts is associated with protein aggregation stress characterized by an increase of protein aggregates. This stress is combined with BAG1 to BAG3 switch, NFκB activation and up-regulation of BAG3/HSPB8 complexes that ensure preferential routing of misfolded/aggregated proteins to autophagy rather than to deficient 26S proteasome. In this context, restoration of pre-existing alterations of protein quality control processes might represent an alternative strategy for DMD therapies.

Effects of Ghrelin on Triglyceride Accumulation and Glucose Uptake in Primary Cultured Rat Myoblasts under Palmitic Acid-Induced High Fat Conditions

Directory of Open Access Journals (Sweden)

Lingling Han

2015-01-01

Full Text Available This study aimed to study the effects of acylated ghrelin on glucose and triglyceride metabolism in rat myoblasts under palmitic acid- (PA- induced high fat conditions. Rat myoblasts were treated with 0, 10−11, 10−9, or 10−7 M acylated ghrelin and 0.3 mM PA for 12 h. Triglyceride accumulation was determined by Oil-Red-O staining and the glycerol phosphate dehydrogenase-peroxidase enzymatic method, and glucose uptake was determined by isotope tracer. The glucose transporter 4 (GLUT4, AMP-activated protein kinase (AMPK, acetyl-CoA carboxylase (ACC, and uncoupling protein 3 (UCP3 were assessed by RT-PCR and western blot. Compared to 0.3 mM PA, ghrelin at 10−9 and 10−7 M reduced triglyceride content (5.855 ± 0.352 versus 5.030 ± 0.129 and 4.158 ± 0.254 mM, P<0.05 and prevented PA-induced reduction of glucose uptake (1.717 ± 0.264 versus 2.233 ± 0.333 and 2.333 ± 0.273 10−2 pmol/g/min, P<0.05. The relative protein expression of p-AMPKα/AMPKα, UCP3, and p-ACC under 0.3 mM PA was significantly reduced compared to controls (all P<0.05, but those in the 10−9 and 10−7 M ghrelin groups were significantly protected from 0.3 mM PA (all P<0.05. In conclusion, acylated ghrelin reduced PA-induced triglyceride accumulation and prevented the PA-induced decrease in glucose uptake in rat myoblasts. These effects may involve fatty acid oxidation.

Lipopolysaccharide inhibits myogenic differentiation of C2C12 myoblasts through the Toll-like receptor 4-nuclear factor-κB signaling pathway and myoblast-derived tumor necrosis factor-α.

Directory of Open Access Journals (Sweden)

Yuko Ono

Full Text Available Circulating lipopolysaccharide (LPS concentrations are often elevated in patients with sepsis or with various endogenous diseases that are associated with metabolic endotoxemia. Involuntary loss of skeletal muscle, termed muscle wasting, is commonly observed in these conditions, suggesting that circulating LPS might play an essential role in its development. Although impairment of muscle regeneration is an important determinant of skeletal muscle wasting, it is unclear whether LPS affects this process and, if so, by what mechanism. Here, we used the C2C12 myoblast cell line to investigate the effects of LPS on myogenesis.C2C12 myoblasts were grown to 80% confluence and induced to differentiate in the absence or presence of LPS (0.1 or 1 μg/mL; TAK-242 (1 μM, a specific inhibitor of Toll-like receptor 4 (TLR4 signaling; and a tumor necrosis factor (TNF-α neutralizing antibody (5 μg/mL. Expression of a skeletal muscle differentiation marker (myosin heavy chain II, two essential myogenic regulatory factors (myogenin and MyoD, and a muscle negative regulatory factor (myostatin was analyzed by western blotting. Nuclear factor-κB (NF-κB DNA-binding activity was measured using an enzyme-linked immunosorbent assay.LPS dose-dependently and significantly decreased the formation of multinucleated myotubes and the expression of myosin heavy chain II, myogenin, and MyoD, and increased NF-κB DNA-binding activity and myostatin expression. The inhibitory effect of LPS on myogenic differentiation was reversible, suggesting that it was not caused by nonspecific toxicity. Both TAK-242 and anti-TNF-α reduced the LPS-induced increase in NF-κB DNA-binding activity, downregulation of myogenic regulatory factors, and upregulation of myostatin, thereby partially rescuing the impairment of myogenesis.Our data suggest that LPS inhibits myogenic differentiation via a TLR4-NF-κB-dependent pathway and an autocrine/paracrine TNF-α-induced pathway. These pathways

Feasibility of dual reporter gene in rat myoblast cell line using human sodium iodide symporter (hNIS) and enhanced green fluorescent protein (EGFP) gene

Energy Technology Data Exchange (ETDEWEB)

Lee, Yong Jin; Lee, You La; Ahn, Sohn Joo; Choi, Chang Ik; Lee, Sang Woo; Ahn, Byeong Cheol; Lee, Jae Tae [School of Medicine, Kyungpook National University, Daegu (Korea, Republic of)

2007-07-01

To develop a non-invasive combined imaging method of gamma camera and optical imaging to assess rat myoblast cell line, H9c2, we constructed retrovirus containing hNIS and EGFP gene, and transfected to rat myoblast cell and monitored hNIS and EGFP expression. Rat myoblast cell line, H9C2, was transfected with hNIS and EGFP gene using retrovirus (H9C2-NG). The expression of hNIS and EGFP gene was determined by RT-PCR and fluorescence microscopy, respectively. The uptake and efflux of I-125 were measured in the transfected and wild type cell lines. Each cell line was injected to 4 flank sites (H9c2: 1X107 or 2X107, H9C2-NG: 1X107 or 2X107) in nude mouse. Scintigraphic image was performed at 3h, 1 day after H9C2 and H9C2-NG cell inoculation. We performed gamma camera and animal PET imaging to evaluate NIS expression. Also, GFP image obtained using optical imaging system. The expression of hNIS and EGFP gene was confirmed by RT-PCR. In iodide uptake, H9C2-NG cells accumulated 274.52.2 pmol/ mg protein at 30 min. But wild type cell line did not uptake iodide. In fluorescent microscopy, H9C2-NG cells were highly fluorescent than that of H9C2 cells. In iodide efflux study, 50% of radioactivity flowed out during the first 10min. Scintigraphy showed increased uptake of Tc-99m in H9c2-NG than in H9C2 for 1 day. Also, H9C2-NG cells showed high signal-to-background fluorescent spots in animal body. In this study, NIS and EGFP reporter gene were successfully transfected by a retrovirus in myoblast cell line, and the transfected cell can be easily visualized in vivo. These results suggest that NIS and EGFP gene has an excellent feasibility as a reporter gene, and it can be used to monitor cell trafficking for monitoring.

Wnt/β-catenin signaling changes C2C12 myoblast proliferation and differentiation by inducing Id3 expression

International Nuclear Information System (INIS)

Zhang, Long; Shi, Songting; Zhang, Juan; Zhou, Fangfang; Dijke, Peter ten

2012-01-01

Highlights: ► Expression of Id3 but not Id1 is induced by Wnt3a stimulation in C2C12 cells. ► Wnt3a induces Id3 expression via canonical Wnt/β-catenin pathway. ► Wnt3a-induced Id3 expression does not depend on BMP signaling activation. ► Induction of Id3 expression is critical determinant in Wnt3a-induced cell proliferation and differentiation. -- Abstract: Canonical Wnt signaling plays important roles in regulating cell proliferation and differentiation. In this study, we report that inhibitor of differentiation (Id)3 is a Wnt-inducible gene in mouse C2C12 myoblasts. Wnt3a induced Id3 expression in a β-catenin-dependent manner. Bone morphogenetic protein (BMP) also potently induced Id3 expression. However, Wnt-induced Id3 expression occurred independent of the BMP/Smad pathway. Functional studies showed that Id3 depletion in C2C12 cells impaired Wnt3a-induced cell proliferation and alkaline phosphatase activity, an early marker of osteoblast cells. Id3 depletion elevated myogenin induction during myogenic differentiation and partially impaired Wnt3a suppressed myogenin expression in C2C12 cells. These results suggest that Id3 is an important Wnt/β-catenin induced gene in myoblast cell fate determination.

The effect of low intensity shockwave treatment (Li-SWT) on human myoblasts and mouse skeletal muscle

DEFF Research Database (Denmark)

Hansen, Lise K; Schrøder, Henrik D; Lund, Lars

2017-01-01

, proliferation and differentiation were tested. Cardiotoxin induced injury was created in tibialis anterior muscles of 28 mice, and two days later, the lesions were treated with 500 impulses of Li-SWT on one of the legs. The treatment was repeated every third day of the period and ended on day 14 after...... incremental effect on expression of pro-angiogenic genes. However, we found no changes in the number of PAX7 positive cells or blood vessel density in Li-SWT treated and control muscle. Furthermore, Li-SWT in the selected doses did not decrease survival, proliferation or differentiation of myoblasts in vitro....

Combined use of bone marrow-derived mesenchymal stromal cells (BM-MSCs) and platelet rich plasma (PRP) stimulates proliferation and differentiation of myoblasts in vitro: new therapeutic perspectives for skeletal muscle repair/regeneration.

Science.gov (United States)

Sassoli, Chiara; Vallone, Larissa; Tani, Alessia; Chellini, Flaminia; Nosi, Daniele; Zecchi-Orlandini, Sandra

2018-02-05

Satellite cell-mediated skeletal muscle repair/regeneration is compromised in cases of extended damage. Bone marrow mesenchymal stromal cells (BM-MSCs) hold promise for muscle healing but some criticisms hamper their clinical application, including the need to avoid animal serum contamination for expansion and the scarce survival after transplant. In this context, platelet-rich plasma (PRP) could offer advantages. Here, we compare the effects of PRP or standard culture media on C2C12 myoblast, satellite cell and BM-MSC viability, survival, proliferation and myogenic differentiation and evaluate PRP/BM-MSC combination effects in promoting myogenic differentiation. PRP induced an increase of mitochondrial activity and Ki67 expression comparable or even greater than that elicited by standard media and promoted AKT signaling activation in myoblasts and BM-MSCs and Notch-1 pathway activation in BM-MSCs. It stimulated MyoD, myogenin, α-sarcomeric actin and MMP-2 expression in myoblasts and satellite cell activation. Notably, PRP/BM-MSC combination was more effective than PRP alone. We found that BM-MSCs influenced myoblast responses through a paracrine activation of AKT signaling, contributing to shed light on BM-MSC action mechanisms. Our results suggest that PRP represents a good serum substitute for BM-MSC manipulation in vitro and could be beneficial towards transplanted cells in vivo. Moreover, it might influence muscle resident progenitors' fate, thus favoring the endogenous repair/regeneration mechanisms. Finally, within the limitations of an in vitro experimentation, this study provides an experimental background for considering the PRP/BM-MSC combination as a potential therapeutic tool for skeletal muscle damage, combining the beneficial effects of BM-MSCs and PRP on muscle tissue, while potentiating BM-MSC functionality.

Long-Term Endurance Exercise in Humans Stimulates Cell Fusion of Myoblasts along with Fusogenic Endogenous Retroviral Genes In Vivo.

Directory of Open Access Journals (Sweden)

Sebastian Frese

Full Text Available Myogenesis is defined as growth, differentiation and repair of muscles where cell fusion of myoblasts to multinucleated myofibers is one major characteristic. Other cell fusion events in humans are found with bone resorbing osteoclasts and placental syncytiotrophoblasts. No unifying gene regulation for natural cell fusions has been found. We analyzed skeletal muscle biopsies of competitive cyclists for muscle-specific attributes and expression of human endogenous retrovirus (ERV envelope genes due to their involvement in cell fusion of osteoclasts and syncytiotrophoblasts. Comparing muscle biopsies from post- with the pre-competitive seasons a significant 2.25-fold increase of myonuclei/mm fiber, a 2.38-fold decrease of fiber area/nucleus and a 3.1-fold decrease of satellite cells (SCs occurred. We propose that during the pre-competitive season SC proliferation occurred following with increased cell fusion during the competitive season. Expression of twenty-two envelope genes of muscle biopsies demonstrated a significant increase of putative muscle-cell fusogenic genes Syncytin-1 and Syncytin-3, but also for the non-fusogenic erv3. Immunohistochemistry analyses showed that Syncytin-1 mainly localized to the sarcolemma of myofibers positive for myosin heavy-chain isotypes. Cellular receptors SLC1A4 and SLC1A5 of Syncytin-1 showed significant decrease of expression in post-competitive muscles compared with the pre-competitive season, but only SLC1A4 protein expression localized throughout the myofiber. Erv3 protein was strongly expressed throughout the myofiber, whereas envK1-7 localized to SC nuclei and myonuclei. Syncytin-1 transcription factors, PPARγ and RXRα, showed no protein expression in the myofiber, whereas the pCREB-Ser133 activator of Syncytin-1 was enriched to SC nuclei and myonuclei. Syncytin-1, Syncytin-3, SLC1A4 and PAX7 gene regulations along with MyoD1 and myogenin were verified during proliferating or actively-fusing human

α-linolenic acid reduces TNF-induced apoptosis in C2C12 myoblasts by regulating expression of apoptotic proteins

Directory of Open Access Journals (Sweden)

Felicia Carotenuto

2016-11-01

Full Text Available Impaired regeneration and consequent muscle wasting is a major feature of muscle degenerative diseases. Nutritional interventions as adjuvant strategy for preventing such conditions are recently gaining increasing attention. Ingestion of n3-polyunsaturated fatty acids has been suggested to have a positive impact on muscle diseases. We recently demonstrated that the dietary n3-fatty acid, alpha-linolenic acid (ALA, exerts potent beneficial effects in preserving skeletal muscle regeneration in models of muscle dystrophy. To better elucidate the underlying mechanism we investigate here on the expression level of the anti- and pro-apototic proteins, as well as caspase-3 activity, in C2C12 myoblasts challenged with pathological levels of TNF. The results demonstrated that ALA protective effect on C2C12 myoblasts was associated to an increased Bcl-2/Bax ratio. Indeed, the effect of ALA was directed to rescue Bcl-2 expression and decrease Bax expression both affected in an opposite way by TNF treatment. This effect was associated with a decrease in caspase-3 activity by ALA. TNF is a major pro-inflammatory cytokine that is expressed in damaged skeletal muscle, therefore, counteract inflammatory signals in the muscle microenvironment represents a critical strategy to ameliorate skeletal muscle pathologies

Effect of oxygen tension on bioenergetics and proteostasis in young and old myoblast precursor cells.

Science.gov (United States)

Konigsberg, M; Pérez, V I; Ríos, C; Liu, Y; Lee, S; Shi, Y; Van Remmen, H

2013-01-01

In the majority of studies using primary cultures of myoblasts, the cells are maintained at ambient oxygen tension (21% O2), despite the fact that physiological O2 at the tissue level in vivo is much lower (~1-5% O2). We hypothesized that the cellular response in presence of high oxygen concentration might be particularly important in studies comparing energetic function or oxidative stress in cells isolated from young versus old animals. To test this, we asked whether oxygen tension plays a role in mitochondrial bioenergetics (oxygen consumption, glycolysis and fatty acid oxidation) or oxidative damage to proteins (protein disulfides, carbonyls and aggregates) in myoblast precursor cells (MPCs) isolated from young (3-4 m) and old (29-30 m) C57BL/6 mice. MPCs were grown under physiological (3%) or ambient (21%) O2 for two weeks prior to exposure to an acute oxidative insult (H2O2). Our results show significantly higher basal mitochondrial respiration in young versus old MPCs, an increase in basal respiration in young MPCs maintained at 3% O2 compared to cells maintained at 21% O2, and a shift toward glycolytic metabolism in old MPCs grown at 21% O2. H2O2 treatment significantly reduced respiration in old MPCs grown at 3% O2 but did not further repress respiration at 21% O2 in old MPCs. Oxidative damage to protein was higher in cells maintained at 21% O2 and increased in response to H2O2 in old MPCs. These data underscore the importance of understanding the effect of ambient oxygen tension in cell culture studies, in particular studies measuring oxidative damage and mitochondrial function.

Degree of Suppression of Mouse Myoblast Cell Line C₂C12 Differentiation Varies According to Chondroitin Sulfate Subtype.

Science.gov (United States)

Warita, Katsuhiko; Oshima, Nana; Takeda-Okuda, Naoko; Tamura, Jun-Ichi; Hosaka, Yoshinao Z

2016-10-21

Chondroitin sulfate (CS), a type of glycosaminoglycan (GAG), is a factor involved in the suppression of myogenic differentiation. CS comprises two repeating sugars and has different subtypes depending on the position and number of bonded sulfate groups. However, the effect of each subtype on myogenic differentiation remains unclear. In this study, we spiked cultures of C₂C 12 myoblasts, cells which are capable of undergoing skeletal muscle differentiation, with one of five types of CS (CS-A, -B, -C, -D, or -E) and induced differentiation over a fixed time. After immunostaining of the formed myotubes with an anti-MHC antibody, we counted the number of nuclei in the myotubes and then calculated the fusion index (FI) as a measure of myotube differentiation. The FI values of all the CS-treated groups were lower than the FI value of the control group, especially the group treated with CS-E, which displayed notable suppression of myotube formation. To confirm that the sugar chain in CS-E is important in the suppression of differentiation, chondroitinase ABC (ChABC), which catabolizes CS, was added to the media. The addition of ChABC led to the degradation of CS-E, and neutralized the suppression of myotube formation by CS-E. Collectively, it can be concluded that the degree of suppression of differentiation depends on the subtype of CS and that CS-E strongly suppresses myogenic differentiation. We conclude that the CS sugar chain has inhibitory action against myoblast cell fusion.

Detection of Pancreatic Cancer-Induced Cachexia Using a Fluorescent Myoblast Reporter System and Analysis of Metabolite Abundance.

Science.gov (United States)

Winnard, Paul T; Bharti, Santosh K; Penet, Marie-France; Marik, Radharani; Mironchik, Yelena; Wildes, Flonne; Maitra, Anirban; Bhujwalla, Zaver M

2016-03-15

The dire effects of cancer-induced cachexia undermine treatment and contribute to decreased survival rates. Therapeutic options for this syndrome are limited, and therefore efforts to identify signs of precachexia in cancer patients are necessary for early intervention. The applications of molecular and functional imaging that would enable a whole-body "holistic" approach to this problem may lead to new insights and advances for diagnosis and treatment of this syndrome. Here we have developed a myoblast optical reporter system with the purpose of identifying early cachectic events. We generated a myoblast cell line expressing a dual tdTomato:GFP construct that was grafted onto the muscle of mice-bearing human pancreatic cancer xenografts to provide noninvasive live imaging of events associated with cancer-induced cachexia (i.e., weight loss). Real-time optical imaging detected a strong tdTomato fluorescent signal from skeletal muscle grafts in mice with weight losses of only 1.2% to 2.7% and tumor burdens of only approximately 79 to 170 mm(3). Weight loss in cachectic animals was also associated with a depletion of lipid, cholesterol, valine, and alanine levels, which may provide informative biomarkers of cachexia. Taken together, our findings demonstrate the utility of a reporter system that is capable of tracking tumor-induced weight loss, an early marker of cachexia. Future studies incorporating resected tissue from human pancreatic ductal adenocarcinoma into a reporter-carrying mouse may be able to provide a risk assessment of cachexia, with possible implications for therapeutic development. ©2015 American Association for Cancer Research.

Culture Conditions Affect Expression of DUX4 in FSHD Myoblasts

Directory of Open Access Journals (Sweden)

Sachchida Nand Pandey

2015-05-01

Full Text Available Facioscapulohumeral muscular dystrophy (FSHD is believed to be caused by aberrant expression of double homeobox 4 (DUX4 due to epigenetic changes of the D4Z4 region at chromosome 4q35. Detecting DUX4 is challenging due to its stochastic expression pattern and low transcription level. In this study, we examined different cDNA synthesis strategies and the sensitivity for DUX4 detection. In addition, we investigated the effects of dexamethasone and knockout serum replacement (KOSR on DUX4 expression in culture. Our data showed that DUX4 was consistently detected in cDNA samples synthesized using Superscript III. The sensitivity of DUX4 detection was higher in the samples synthesized using oligo(dT primers compared to random hexamers. Adding dexamethasone to the culture media significantly suppressed DUX4 expression in immortalized (1.3 fold, p < 0.01 and primary (4.7 fold, p < 0.01 FSHD myoblasts, respectively. Culture medium with KOSR increased DUX4 expression and the response is concentration dependent. The findings suggest that detection strategies and culture conditions should be carefully considered when studying DUX4 in cultured cells.

Thimerosal-induced apoptosis in mouse C2C12 myoblast cells occurs through suppression of the PI3K/Akt/survivin pathway.

Directory of Open Access Journals (Sweden)

Wen-Xue Li

Full Text Available BACKGROUND: Thimerosal, a mercury-containing preservative, is one of the most widely used preservatives and found in a variety of biological products. Concerns over its possible toxicity have reemerged recently due to its use in vaccines. Thimerosal has also been reported to be markedly cytotoxic to neural tissue. However, little is known regarding thimerosal-induced toxicity in muscle tissue. Therefore, we investigated the cytotoxic effect of thimerosal and its possible mechanisms on mouse C2C12 myoblast cells. METHODOLOGY/PRINCIPAL FINDINGS: The study showed that C2C12 myoblast cells underwent inhibition of proliferation and apoptosis after exposure to thimerosal (125-500 nM for 24, 48 and 72 h. Thimerosal caused S phase arrest and induced apoptosis as assessed by flow cytometric analysis, Hoechst staining and immunoblotting. The data revealed that thimerosal could trigger the leakage of cytochrome c from mitochondria, followed by cleavage of caspase-9 and caspase-3, and that an inhibitor of caspase could suppress thimerosal-induced apoptosis. Thimerosal inhibited the phosphorylation of Akt(ser473 and survivin expression. Wortmannin, a PI3K inhibitor, inhibited Akt activity and decreased survivin expression, resulting in increased thimerosal-induced apoptosis in C2C12 cells, while the activation of PI3K/Akt pathway by mIGF-I (50 ng/ml increased the expression of survivin and attenuated apoptosis. Furthermore, the inhibition of survivin expression by siRNA enhanced thimerosal-induced cell apoptosis, while overexpression of survivin prevented thimerosal-induced apoptosis. Taken together, the data show that the PI3K/Akt/survivin pathway plays an important role in the thimerosal-induced apoptosis in C2C12 cells. CONCLUSIONS/SIGNIFICANCE: Our results suggest that in C2C12 myoblast cells, thimerosal induces S phase arrest and finally causes apoptosis via inhibition of PI3K/Akt/survivin signaling followed by activation of the mitochondrial apoptotic

Effective myotube formation in human adipose tissue-derived stem cells expressing dystrophin and myosin heavy chain by cellular fusion with mouse C2C12 myoblasts

Energy Technology Data Exchange (ETDEWEB)

Eom, Young Woo [Cell Therapy and Tissue Engineering Center, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Biomedical Research Institute, Lifeliver Co., Ltd., Suwon (Korea, Republic of); Lee, Jong Eun; Yang, Mal Sook; Jang, In Keun; Kim, Hyo Eun; Lee, Doo Hoon; Kim, Young Jin [Biomedical Research Institute, Lifeliver Co., Ltd., Suwon (Korea, Republic of); Park, Won Jin [Dr. Park' s Aesthetic Clinic, Seoul (Korea, Republic of); Kong, Jee Hyun; Shim, Kwang Yong [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Lee, Jong In, E-mail: oncochem@yonsei.ac.kr [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of); Kim, Hyun Soo, E-mail: khsmd@unitel.co.kr [Department of Hematology-Oncology, Wonju College of Medicine, Yonsei Univ., Wonju (Korea, Republic of)

2011-04-29

Highlights: {yields} hASCs were differentiated into skeletal muscle cells by treatment with 5-azacytidine, FGF-2, and the supernatant of cultured hASCs. {yields} Dystrophin and MyHC were expressed in late differentiation step by treatment with the supernatant of cultured hASCs. {yields} hASCs expressing dystrophin and MyHC contributed to myotube formation during co-culture with mouse myoblast C2C12 cells. -- Abstract: Stem cell therapy for muscular dystrophies requires stem cells that are able to participate in the formation of new muscle fibers. However, the differentiation steps that are the most critical for this process are not clear. We investigated the myogenic phases of human adipose tissue-derived stem cells (hASCs) step by step and the capability of myotube formation according to the differentiation phase by cellular fusion with mouse myoblast C2C12 cells. In hASCs treated with 5-azacytidine and fibroblast growth factor-2 (FGF-2) for 1 day, the early differentiation step to express MyoD and myogenin was induced by FGF-2 treatment for 6 days. Dystrophin and myosin heavy chain (MyHC) expression was induced by hASC conditioned medium in the late differentiation step. Myotubes were observed only in hASCs undergoing the late differentiation step by cellular fusion with C2C12 cells. In contrast, hASCs that were normal or in the early stage were not involved in myotube formation. Our results indicate that stem cells expressing dystrophin and MyHC are more suitable for myotube formation by co-culture with myoblasts than normal or early differentiated stem cells expressing MyoD and myogenin.

Effective myotube formation in human adipose tissue-derived stem cells expressing dystrophin and myosin heavy chain by cellular fusion with mouse C2C12 myoblasts

International Nuclear Information System (INIS)

Eom, Young Woo; Lee, Jong Eun; Yang, Mal Sook; Jang, In Keun; Kim, Hyo Eun; Lee, Doo Hoon; Kim, Young Jin; Park, Won Jin; Kong, Jee Hyun; Shim, Kwang Yong; Lee, Jong In; Kim, Hyun Soo

2011-01-01

Highlights: → hASCs were differentiated into skeletal muscle cells by treatment with 5-azacytidine, FGF-2, and the supernatant of cultured hASCs. → Dystrophin and MyHC were expressed in late differentiation step by treatment with the supernatant of cultured hASCs. → hASCs expressing dystrophin and MyHC contributed to myotube formation during co-culture with mouse myoblast C2C12 cells. -- Abstract: Stem cell therapy for muscular dystrophies requires stem cells that are able to participate in the formation of new muscle fibers. However, the differentiation steps that are the most critical for this process are not clear. We investigated the myogenic phases of human adipose tissue-derived stem cells (hASCs) step by step and the capability of myotube formation according to the differentiation phase by cellular fusion with mouse myoblast C2C12 cells. In hASCs treated with 5-azacytidine and fibroblast growth factor-2 (FGF-2) for 1 day, the early differentiation step to express MyoD and myogenin was induced by FGF-2 treatment for 6 days. Dystrophin and myosin heavy chain (MyHC) expression was induced by hASC conditioned medium in the late differentiation step. Myotubes were observed only in hASCs undergoing the late differentiation step by cellular fusion with C2C12 cells. In contrast, hASCs that were normal or in the early stage were not involved in myotube formation. Our results indicate that stem cells expressing dystrophin and MyHC are more suitable for myotube formation by co-culture with myoblasts than normal or early differentiated stem cells expressing MyoD and myogenin.

Enhanced contractile force generation by artificial skeletal muscle tissues using IGF-I gene-engineered myoblast cells.

Science.gov (United States)

Sato, Masanori; Ito, Akira; Kawabe, Yoshinori; Nagamori, Eiji; Kamihira, Masamichi

2011-09-01

The aim of this study was to investigate whether insulin-like growth factor (IGF)-I gene delivery to myoblast cells promotes the contractile force generated by hydrogel-based tissue-engineered skeletal muscles in vitro. Two retroviral vectors allowing doxycycline (Dox)-inducible expression of the IGF-I gene were transduced into mouse myoblast C2C12 cells to evaluate the effects of IGF-I gene expression on these cells. IGF-I gene expression stimulated the proliferation of C2C12 cells, and a significant increase in the growth rate was observed for IGF-I-transduced C2C12 cells with Dox addition, designated C2C12/IGF (Dox+) cells. Quantitative morphometric analyses showed that the myotubes induced from C2C12/IGF (Dox+) cells had a larger area and a greater width than control myotubes induced from normal C2C12 cells. Artificial skeletal muscle tissues were prepared from the respective cells using hydrogels composed of type I collagen and Matrigel. Western blot analyses revealed that the C2C12/IGF (Dox+) tissue constructs showed activation of a skeletal muscle hypertrophy marker (Akt) and enhanced expression of muscle-specific markers (myogenin, myosin heavy chain and tropomyosin). Moreover, the creatine kinase activity was increased in the C2C12/IGF (Dox+) tissue constructs. The C2C12/IGF (Dox+) tissue constructs contracted in response to electrical pulses, and generated a significantly higher physical force than the control C2C12 tissue constructs. These findings indicate that IGF-I gene transfer has the potential to yield functional skeletal muscle substitutes that are capable of in vivo restoration of the load-bearing function of injured muscle or acting as in vitro electrically-controlled bio-actuators. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Automated high-content assay for compounds selectively toxic to Trypanosoma cruzi in a myoblastic cell line.

Directory of Open Access Journals (Sweden)

Julio Alonso-Padilla

2015-01-01

Full Text Available Chagas disease, caused by the protozoan parasite Trypanosoma cruzi, represents a very important public health problem in Latin America where it is endemic. Although mostly asymptomatic at its initial stage, after the disease becomes chronic, about a third of the infected patients progress to a potentially fatal outcome due to severe damage of heart and gut tissues. There is an urgent need for new drugs against Chagas disease since there are only two drugs available, benznidazole and nifurtimox, and both show toxic side effects and variable efficacy against the chronic stage of the disease.Genetically engineered parasitic strains are used for high throughput screening (HTS of large chemical collections in the search for new anti-parasitic compounds. These assays, although successful, are limited to reporter transgenic parasites and do not cover the wide T. cruzi genetic background. With the aim to contribute to the early drug discovery process against Chagas disease we have developed an automated image-based 384-well plate HTS assay for T. cruzi amastigote replication in a rat myoblast host cell line. An image analysis script was designed to inform on three outputs: total number of host cells, ratio of T. cruzi amastigotes per cell and percentage of infected cells, which respectively provides one host cell toxicity and two T. cruzi toxicity readouts. The assay was statistically robust (Z´ values >0.6 and was validated against a series of known anti-trypanosomatid drugs.We have established a highly reproducible, high content HTS assay for screening of chemical compounds against T. cruzi infection of myoblasts that is amenable for use with any T. cruzi strain capable of in vitro infection. Our visual assay informs on both anti-parasitic and host cell toxicity readouts in a single experiment, allowing the direct identification of compounds selectively targeted to the parasite.

Functional analysis of SH3 domain containing ring finger 2 during the myogenic differentiation of quail myoblast cells

Directory of Open Access Journals (Sweden)

Si Won Kim

2017-08-01

Full Text Available Objective Owing to the public availability of complete genome sequences, including avian species, massive bioinformatics analyses may be conducted for computational gene prediction and the identification of gene regulatory networks through various informatics tools. However, to evaluate the biofunctional activity of a predicted target gene, in vivo and in vitro functional genomic analyses should be a prerequisite. Methods Due to a lack of quail genomic sequence information, we first identified the partial genomic structure and sequences of the quail SH3 domain containing ring finger 2 (SH3RF2 gene. Subsequently, SH3RF2 was knocked out using clustered regularly interspaced short palindromic repeat/Cas9 technology and single cell-derived SH3RF2 mutant sublines were established to study the biofunctional activity of SH3RF2 in quail myoblast (QM7 cells during muscle differentiation. Results Through a T7 endonuclease I assay and genotyping analysis, we established an SH3RF2 knockout (KO QM7#4 subline with 61 and 155 nucleotide deletion mutations in SH3RF2. After the induction of myotube differentiation, the expression profiles were analyzed and compared between regular QM7 and SH3RF2 KO QM7#4 cells by global RNA sequencing and bioinformatics analysis. Conclusion We did not detect any statistically significant role of SH3RF2 during myotube differentiation in QM7 myoblast cells. However, additional experiments are necessary to examine the biofunctional activity of SH3RF2 in cell proliferation and muscle growth.

Morphofunctional and Biochemical Approaches for Studying Mitochondrial Changes during Myoblasts Differentiation

Directory of Open Access Journals (Sweden)

Elena Barbieri

2011-01-01

Full Text Available This study describes mitochondrial behaviour during the C2C12 myoblast differentiation program and proposes a proteomic approach to mitochondria integrated with classical morphofunctional and biochemical analyses. Mitochondrial ultrastructure variations were determined by transmission electron microscopy; mitochondrial mass and membrane potential were analysed by Mitotracker Green and JC-1 stains and by epifluorescence microscope. Expression of PGC1 , NRF1 , and Tfam genes controlling mitochondrial biogenesis was studied by real-time PCR. The mitochondrial functionality was tested by cytochrome c oxidase activity and COXII expression. Mitochondrial proteomic profile was also performed. These assays showed that mitochondrial biogenesis and activity significantly increase in differentiating myotubes. The proteomic profile identifies 32 differentially expressed proteins, mostly involved in oxidative metabolism, typical of myotubes formation. Other notable proteins, such as superoxide dismutase (MnSOD, a cell protection molecule, and voltage-dependent anion-selective channel protein (VDAC1 involved in the mitochondria-mediated apoptosis, were found to be regulated by the myogenic process. The integration of these approaches represents a helpful tool for studying mitochondrial dynamics, biogenesis, and functionality in comparative surveys on mitochondrial pathogenic or senescent satellite cells.

Halogenated anaesthetics and cardiac protection in cardiac and non-cardiac anaesthesia

Directory of Open Access Journals (Sweden)

Landoni Giovanni

2009-01-01

Full Text Available Volatile anaesthetic agents have direct protective properties against ischemic myocardial damage. The implementation of these properties during clinical anaesthesia can provide an additional tool in the treatment or prevention, or both, of ischemic cardiac dysfunction in the perioperative period. A recent meta-analysis showed that desflurane and sevoflurane reduce postoperative mortality and incidence of myocardial infarction following cardiac surgery, with significant advantages in terms of postoperative cardiac troponin release, need for inotrope support, time on mechanical ventilation, intensive care unit and overall hospital stay. Multicentre, randomised clinical trials had previously demonstrated that the use of desflurane can reduce the postoperative release of cardiac troponin I, the need for inotropic support, and the number of patients requiring prolonged hospitalisation following coronary artery bypass graft surgery either with and without cardiopulmonary bypass. The American College of Cardiology/American Heart Association Guidelines recommend volatile anaesthetic agents during non-cardiac surgery for the maintenance of general anaesthesia in patients at risk for myocardial infarction. Nonetheless, e vidence in non-coronary surgical settings is contradictory and will be reviewed in this paper together with the mechanisms of cardiac protection by volatile agents.

Cardiac fusion and complex congenital cardiac defects in thoracopagus twins: diagnostic value of cardiac CT

Energy Technology Data Exchange (ETDEWEB)

Goo, Hyun Woo [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Park, Jeong-Jun [University of Ulsan College of Medicine, Asan Medical Center, Department of Pediatric Cardiac Surgery, Seoul (Korea, Republic of); Kim, Ellen Ai-Rhan [University of Ulsan College of Medicine, Asan Medical Center, Division of Neonatology, Department of Pediatrics, Seoul (Korea, Republic of); Won, Hye-Sung [University of Ulsan College of Medicine, Asan Medical Center, Department of Obstetrics and Gynecology, Seoul (Korea, Republic of)

2014-09-15

Most thoracopagus twins present with cardiac fusion and associated congenital cardiac defects, and assessment of this anatomy is of critical importance in determining patient care and outcome. Cardiac CT with electrocardiographic triggering provides an accurate and quick morphological assessment of both intracardiac and extracardiac structures in newborns, making it the best imaging modality to assess thoracopagus twins during the neonatal period. In this case report, we highlight the diagnostic value of cardiac CT in thoracopagus twins with an interatrial channel and complex congenital cardiac defects. (orig.)

Photobiomodulation Protects and Promotes Differentiation of C2C12 Myoblast Cells Exposed to Snake Venom.

Directory of Open Access Journals (Sweden)

Luciana Miato Gonçalves Silva

Full Text Available Snakebites is a neglected disease and in Brazil is considered a serious health problem, with the majority of the snakebites caused by the genus Bothrops. Antivenom therapy and other first-aid treatments do not reverse local myonecrose which is the main sequel caused by the envenomation. Several studies have shown the effectiveness of low level laser (LLL therapy in reducing local myonecrosis induced by Bothropic venoms, however the mechanism involved in this effect is unknown. In this in vitro study, we aimed to analyze the effect of LLL irradiation against cytotoxicity induced by Bothrops jararacussu venom on myoblast C2C12 cells.C2C12 were utilized as a model target and were incubated with B. jararacussu venom (12.5 μg/mL and immediately irradiated with LLL at wavelength of red 685 nm or infrared 830 nm with energy density of 2.0, 4.6 and 7.0 J/cm2. Effects of LLL on cellular responses of venom-induced cytotoxicity were examined, including cell viability, measurement of cell damage and intra and extracellular ATP levels, expression of myogenic regulatory factors, as well as cellular differentiation.In non-irradiated cells, the venom caused a decrease in cell viability and a massive release of LDH and CK levels indicating myonecrosis. Infrared and red laser at all energy densities were able to considerably decrease venom-induced cytotoxicity. Laser irradiation induced myoblasts to differentiate into myotubes and this effect was accompanied by up regulation of MyoD and specially myogenin. Moreover, LLL was able to reduce the extracellular while increased the intracellular ATP content after venom exposure. In addition, no difference in the intensity of cytotoxicity was shown by non-irradiated and irradiated venom.LLL irradiation caused a protective effect on C2C12 cells against the cytotoxicity caused by B. jararacussu venom and promotes differentiation of these cells by up regulation of myogenic factors. A modulatory effect of ATP synthesis may

YB1/p32, a nuclear Y-box binding protein 1, is a novel regulator of myoblast differentiation that interacts with Msx1 homeoprotein

Energy Technology Data Exchange (ETDEWEB)

Song, Young Joon [Department of Biological Sciences, College of Natural Science, Inha University, 253 Yonghyun-dong, Nam-Gu, Incheon, Korea, 402-751 (Korea, Republic of); Lee, Hansol, E-mail: hlee@inha.ac.kr [Department of Biological Sciences, College of Natural Science, Inha University, 253 Yonghyun-dong, Nam-Gu, Incheon, Korea, 402-751 (Korea, Republic of)

2010-02-15

Precisely controlled cellular differentiation is essential for the proper development of vertebrate embryo and deregulated differentiation is a major cause of many human congenital diseases as well as cancer. Msx1 is a member of the homeoprotein family implicated in these processes, which inhibits the differentiation of skeletal muscle and other cell types, presumably by regulating transcription of target genes through interaction with other cellular factors. We presently show that YB1/p32, a nuclear Y-box binding protein 1, interacts with Msx1 homeoprotein and functions as a regulator of C2C12 myoblast differentiation. We demonstrate that YB1/p32 functionally interacts with Msx1 through its N-terminal region and colocalizes with Msx1 at the nuclear periphery. Moreover, we find that YB1/p32 is competent for inhibition of C2C12 myoblast differentiation, which is correlated with its activity as a negative regulator of MyoD gene expression and binding to the MyoD core enhancer region (CER). Furthermore, YB1/p32 cooperates with Msx1 in transcriptional repression and knocking down the expression of endogenous YB1 attenuates the effects of Msx1. Taken together, our study has uncovered a new function of YB1/p32, a regulator of skeletal muscle differentiation.

YB1/p32, a nuclear Y-box binding protein 1, is a novel regulator of myoblast differentiation that interacts with Msx1 homeoprotein

International Nuclear Information System (INIS)

Song, Young Joon; Lee, Hansol

2010-01-01

Precisely controlled cellular differentiation is essential for the proper development of vertebrate embryo and deregulated differentiation is a major cause of many human congenital diseases as well as cancer. Msx1 is a member of the homeoprotein family implicated in these processes, which inhibits the differentiation of skeletal muscle and other cell types, presumably by regulating transcription of target genes through interaction with other cellular factors. We presently show that YB1/p32, a nuclear Y-box binding protein 1, interacts with Msx1 homeoprotein and functions as a regulator of C2C12 myoblast differentiation. We demonstrate that YB1/p32 functionally interacts with Msx1 through its N-terminal region and colocalizes with Msx1 at the nuclear periphery. Moreover, we find that YB1/p32 is competent for inhibition of C2C12 myoblast differentiation, which is correlated with its activity as a negative regulator of MyoD gene expression and binding to the MyoD core enhancer region (CER). Furthermore, YB1/p32 cooperates with Msx1 in transcriptional repression and knocking down the expression of endogenous YB1 attenuates the effects of Msx1. Taken together, our study has uncovered a new function of YB1/p32, a regulator of skeletal muscle differentiation.

MicroRNA, miR-374b, directly targets Myf6 and negatively regulates C2C12 myoblasts differentiation

Energy Technology Data Exchange (ETDEWEB)

Ma, Zhiyuan; Sun, Xiaorui; Xu, Dequan; Xiong, Yuanzhu; Zuo, Bo, E-mail: zuobo@mail.hzau.edu.cn

2015-11-27

Myogenesis is a complex process including myoblast proliferation, differentiation and myotube formation and is controlled by myogenic regulatory factors (MRFs), MyoD, MyoG, Myf5 and Myf6 (also known as MRF4). MicroRNA is a kind of ∼22 nt-long non-coding small RNAs, and act as key transcriptional or post-transcriptional regulators of gene expression. Identification of miRNAs involved in the regulation of muscle genes could improve our understanding of myogenesis process. In this study, we investigated the regulation of Myf6 gene by miRNAs. We showed that miR-374b specifically bound to the 3'untranslated region (UTR) of Myf6 and down-regulated the expression of Myf6 gene at both mRNA and protein level. Furthermore, miR-374b is ubiquitously expressed in the tissues of adult C57BL6 mouse, and the mRNA abundance increases first and then decreases during C2C12 myoblasts differentiation. Over-expression of miR-374b impaired C2C12 cell differentiation, while inhibiting miR-374b expression by 2′-O-methyl antisense oligonucleotides promoted C2C12 cell differentiation. Taken together, our findings identified miR-374b directly targets Myf6 and negatively regulates myogenesis. - Highlights: • MiR-374b directly targets 3′UTR of Myf6. • MiR-374b negatively regulates Myf6 in C2C12 cells. • MiR-374b abundance significiently changes during C2C12 cells differentiation. • MiR-374b negatively regulates C2C12 cells differentiation.

Cardiac tamponade: contrast reflux as an indicator of cardiac chamber equalization

Directory of Open Access Journals (Sweden)

Nauta Foeke Jacob

2012-05-01

Full Text Available Abstract Background Traumatic hemopericardium remains a rare entity; it does however commonly cause cardiac tamponade which remains a major cause of death in traumatic blunt cardiac injury. Objectives We present a case of blunt chest trauma complicated by cardiac tamponade causing cardiac chamber equalization revealed by reflux of contrast. Case report A 29-year-old unidentified male suffered blunt chest trauma in a motor vehicle collision. Computed tomography (CT demonstrated a periaortic hematoma and hemopericardium. Significant contrast reflux was seen in the inferior vena cava and hepatic veins suggesting a change in cardiac chamber pressures. After intensive treatment including cardiac massage this patient expired of cardiac arrest. Conclusion Reflux of contrast on CT imaging can be an indicator of traumatic cardiac tamponade.

Living cardiac patch: the elixir for cardiac regeneration.

Science.gov (United States)

Lakshmanan, Rajesh; Krishnan, Uma Maheswari; Sethuraman, Swaminathan

2012-12-01

A thorough understanding of the cellular and muscle fiber orientation in left ventricular cardiac tissue is of paramount importance for the generation of artificial cardiac patches to treat the ischemic myocardium. The major challenge faced during cardiac patch engineering is to choose a perfect combination of three entities; cells, scaffolds and signaling molecules comprising the tissue engineering triad for repair and regeneration. This review provides an overview of various scaffold materials, their mechanical properties and fabrication methods utilized in cardiac patch engineering. Stem cell therapies in clinical trials and the commercially available cardiac patch materials were summarized in an attempt to provide a recent perspective in the treatment of heart failure. Various tissue engineering strategies employed thus far to construct viable thick cardiac patches is schematically illustrated. Though many strategies have been proposed for fabrication of various cardiac scaffold materials, the stage and severity of the disease condition demands the incorporation of additional cues in a suitable scaffold material. The scaffold may be nanofibrous patch, hydrogel or custom designed films. Integration of stem cells and biomolecular cues along with the scaffold may provide the right microenvironment for the repair of unhealthy left ventricular tissue as well as promote its regeneration.

Regulation of cardiac remodeling by cardiac Na/K-ATPase isoforms

Directory of Open Access Journals (Sweden)

Lijun Catherine Liu

2016-09-01

Full Text Available Cardiac remodeling occurs after cardiac pressure/volume overload or myocardial injury during the development of heart failure and is a determinant of heart failure. Preventing or reversing remodeling is a goal of heart failure therapy. Human cardiomyocyte Na+/K+-ATPase has multiple α isoforms (1-3. The expression of the α subunit of the Na+/K+-ATPase is often altered in hypertrophic and failing hearts. The mechanisms are unclear. There are limited data from human cardiomyocytes. Abundant evidences from rodents show that Na+/K+-ATPase regulates cardiac contractility, cell signaling, hypertrophy and fibrosis. The α1 isoform of the Na+/K+-ATPase is the ubiquitous isoform and possesses both pumping and signaling functions. The α2 isoform of the Na+/K+-ATPase regulates intracellular Ca2+ signaling, contractility and pathological hypertrophy. The α3 isoform of the Na+/K+-ATPase may also be a target for cardiac hypertrophy. Restoration of cardiac Na+/K+-ATPase expression may be an effective approach for prevention of cardiac remodeling. In this article, we will overview: (1 the distribution and function of isoform specific Na+/K+-ATPase in the cardiomyocytes. (2 the role of cardiac Na+/K+-ATPase in the regulation of cell signaling, contractility, cardiac hypertrophy and fibrosis in vitro and in vivo. Selective targeting of cardiac Na+/K+-ATPase isoform may offer a new target for the prevention of cardiac remodeling.

Edible Scaffolds Based on Non-Mammalian Biopolymers for Myoblast Growth

Directory of Open Access Journals (Sweden)

Javier Enrione

2017-12-01

Full Text Available In vitro meat has recently emerged as a new concept in food biotechnology. Methods to produce in vitro meat generally involve the growth of muscle cells that are cultured on scaffolds using bioreactors. Suitable scaffold design and manufacture are critical to downstream culture and meat production. Most current scaffolds are based on mammalian-derived biomaterials, the use of which is counter to the desire to obviate mammal slaughter in artificial meat production. Consequently, most of the knowledge is related to the design and control of scaffold properties based on these mammalian-sourced materials. To address this, four different scaffold materials were formulated using non-mammalian sources, namely, salmon gelatin, alginate, and additives including gelling agents and plasticizers. The scaffolds were produced using a freeze-drying process, and the physical, mechanical, and biological properties of the scaffolds were evaluated. The most promising scaffolds were produced from salmon gelatin, alginate, agarose, and glycerol, which exhibited relatively large pore sizes (~200 μm diameter and biocompatibility, permitting myoblast cell adhesion (~40% and growth (~24 h duplication time. The biodegradation profiles of the scaffolds were followed, and were observed to be less than 25% after 4 weeks. The scaffolds enabled suitable myogenic response, with high cell proliferation, viability, and adequate cell distribution throughout. This system composed of non-mammalian edible scaffold material and muscle-cells is promising for the production of in vitro meat.

Initial Efficacy of a Cardiac Rehabilitation Transition Program: Cardiac TRUST

Science.gov (United States)

Zullo, Melissa; Boxer, Rebecca; Moore, Shirley M.

2012-01-01

Patients recovering from cardiac events are increasingly using postacute care, such as home health care and skilled nursing facility services. The purpose of this pilot study was to test the initial efficacy, feasibility, and safety of a specially designed postacute care transitional rehabilitation intervention for cardiac patients. Cardiac Transitional Rehabilitation Using Self- Management Techniques (Cardiac TRUST) is a family-focused intervention that includes progressive low-intensity walking and education in self-management skills to facilitate recovery following a cardiac event. Using a randomized two-group design, exercise self-efficacy, steps walked, and participation in an outpatient cardiac rehabilitation program were compared in a sample of 38 older adults; 17 who received the Cardiac TRUST program and 21 who received usual care only. At discharge from postacute care, the intervention group had a trend for higher levels of self-efficacy for exercise outcomes (X=39.1, SD=7.4) than the usual care group (X=34.5; SD=7.0) (t-test 1.9, p=.06). During the 6 weeks following discharge, compared with the usual care group, the intervention group had more attendance in out-patient cardiac rehabilitation (33% compared to 11.8%, F=7.1, p=.03) and a trend toward more steps walked during the first week (X=1,307, SD=652 compared to X=782, SD=544, t-test 1.8, p=.07). The feasibility of the intervention was better for the home health participants than for those in the skilled nursing facility and there were no safety concerns. The provision of cardiac-focused rehabilitation during postacute care has the potential to bridge the gap in transitional services from hospitalization to outpatient cardiac rehabilitation for these patients at high risk for future cardiac events. Further evidence of the efficacy of Cardiac TRUST is warranted. PMID:22084960

G-protein coupled receptor 56 promotes myoblast fusion through serum response factor- and nuclear factor of activated T-cell-mediated signalling but is not essential for muscle development in vivo.

Science.gov (United States)

Wu, Melissa P; Doyle, Jamie R; Barry, Brenda; Beauvais, Ariane; Rozkalne, Anete; Piao, Xianhua; Lawlor, Michael W; Kopin, Alan S; Walsh, Christopher A; Gussoni, Emanuela

2013-12-01

Mammalian muscle cell differentiation is a complex process of multiple steps for which many of the factors involved have not yet been defined. In a screen to identify the regulators of myogenic cell fusion, we found that the gene for G-protein coupled receptor 56 (GPR56) was transiently up-regulated during the early fusion of human myoblasts. Human mutations in the gene for GPR56 cause the disease bilateral frontoparietal polymicrogyria; however, the consequences of receptor dysfunction on muscle development have not been explored. Using knockout mice, we defined the role of GPR56 in skeletal muscle. GPR56(-/-) myoblasts have decreased fusion and smaller myotube sizes in culture. In addition, a loss of GPR56 expression in muscle cells results in decreases or delays in the expression of myogenic differentiation 1, myogenin and nuclear factor of activated T-cell (NFAT)c2. Our data suggest that these abnormalities result from decreased GPR56-mediated serum response element and NFAT signalling. Despite these changes, no overt differences in phenotype were identified in the muscle of GPR56 knockout mice, which presented only a mild but statistically significant elevation of serum creatine kinase compared to wild-type. In agreement with these findings, clinical data from 13 bilateral frontoparietal polymicrogyria patients revealed mild serum creatine kinase increase in only two patients. In summary, targeted disruption of GPR56 in mice results in myoblast abnormalities. The absence of a severe muscle phenotype in GPR56 knockout mice and human patients suggests that other factors may compensate for the lack of this G-protein coupled receptor during muscle development and that the motor delay observed in these patients is likely not a result of primary muscle abnormalities. © 2013 FEBS.

IGF-II-mediated downregulation of peroxisome proliferator-activated receptor-γ coactivator-1α in myoblast cells involves PI3K/Akt/FoxO1 signaling pathway.

Science.gov (United States)

Mu, Xiaoyu; Qi, Weihong; Liu, Yunzhang; Zhou, Jianfeng; Li, Yun; Rong, Xiaozhi; Lu, Ling

2017-08-01

Insulin-like growth factor II (IGF-II) can stimulate myogenesis and is critically involved in skeletal muscle differentiation. The presence of negative regulators of this process, however, is not well explored. Here, we showed that in myoblast cells, IGF-II negatively regulated peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) mRNA expression, while constitutive expression of PGC-1α induced myoblast differentiation. These results suggest that the negative regulation of PGC-1α by IGF-II may act as a negative feedback mechanism in IGF-II-induced myogenic differentiation. Reporter assays demonstrated that IGF-II suppresses the basal PGC-1α promoter activity. Blocking the IGF-II signaling pathway increased the endogenous PGC-1α levels. In addition, pharmacological inhibition of PI3 kinase activity prevented the downregulation of PGC-1α but the activation of mTOR was not required for this process. Importantly, further analysis showed that forkhead transcription factor FoxO1 contributes to mediating the effects of IGF-II on PGC-1 promoter activity. These findings indicate that IGF-II reduces PGC-1α expression in skeletal muscle cells through a mechanism involving PI3K-Akt-FoxO1 but not p38 MAPK or Erk1/2 MAPK pathways.

Cardiac tumors: optimal cardiac MR sequences and spectrum of imaging appearances.

LENUS (Irish Health Repository)

O'Donnell, David H

2012-02-01

OBJECTIVE: This article reviews the optimal cardiac MRI sequences for and the spectrum of imaging appearances of cardiac tumors. CONCLUSION: Recent technologic advances in cardiac MRI have resulted in the rapid acquisition of images of the heart with high spatial and temporal resolution and excellent myocardial tissue characterization. Cardiac MRI provides optimal assessment of the location, functional characteristics, and soft-tissue features of cardiac tumors, allowing accurate differentiation of benign and malignant lesions.

Cardiac gated ventilation

International Nuclear Information System (INIS)

Hanson, C.W. III; Hoffman, E.A.

1995-01-01

There are several theoretic advantages to synchronizing positive pressure breaths with the cardiac cycle, including the potential for improving distribution of pulmonary and myocardial blood flow and enhancing cardiac output. The authors evaluated the effects of synchronizing respiration to the cardiac cycle using a programmable ventilator and electron beam CT (EBCT) scanning. The hearts of anesthetized dogs were imaged during cardiac gated respiration with a 50 msec scan aperture. Multi slice, short axis, dynamic image data sets spanning the apex to base of the left ventricle were evaluated to determine the volume of the left ventricular chamber at end-diastole and end-systole during apnea, systolic and diastolic cardiac gating. The authors observed an increase in cardiac output of up to 30% with inspiration gated to the systolic phase of the cardiac cycle in a non-failing model of the heart

Human myotubes from myoblast cultures undergoing senescence exhibit defects in glucose and lipid metabolism

DEFF Research Database (Denmark)

Nehlin, Jan O; Just, Marlene; Rustan, Arild C

2011-01-01

Adult stem cells are known to have a finite replication potential. Muscle biopsy-derived human satellite cells (SCs) were grown at different passages and differentiated to human myotubes in culture to analyze the functional state of various carbohydrate and lipid metabolic pathways. As the prolif......Adult stem cells are known to have a finite replication potential. Muscle biopsy-derived human satellite cells (SCs) were grown at different passages and differentiated to human myotubes in culture to analyze the functional state of various carbohydrate and lipid metabolic pathways...... number and could be explained by reduced incorporation into diacyl- and triacylglycerols. The levels of long-chain acyl-CoA esters decreased with increased passage number. Late-passage, non-proliferating, myoblast cultures showed strong senescence-associated β-galactosidase activity indicating...... that the observed metabolic defects accompany the induction of a senescent state. The main function of SCs is regeneration and skeletal muscle-build up. Thus, the metabolic defects observed during aging of SC-derived myotubes could have a role in sarcopenia, the gradual age-related loss of muscle mass and strength....

Cardiac function and cognition in older community-dwelling cardiac patients.

Science.gov (United States)

Eggermont, Laura H P; Aly, Mohamed F A; Vuijk, Pieter J; de Boer, Karin; Kamp, Otto; van Rossum, Albert C; Scherder, Erik J A

2017-11-01

Cognitive deficits have been reported in older cardiac patients. An underlying mechanism for these findings may be reduced cardiac function. The relationship between cardiac function as represented by different echocardiographic measures and different cognitive function domains in older cardiac patients remains unknown. An older (≥70 years) heterogeneous group of 117 community-dwelling cardiac patients under medical supervision by a cardiologist underwent thorough echocardiographic assessment including left ventricular ejection fraction, cardiac index, left atrial volume index, left ventricular mass index, left ventricular diastolic function, and valvular calcification. During a home visit, a neuropsychological assessment was performed within 7.1 ± 3.8 months after echocardiographic assessment; the neuropsychological assessment included three subtests of a word-learning test (encoding, recall, recognition) to examine one memory function domain and three executive function tests, including digit span backwards, Trail Making Test B minus A, and the Stroop colour-word test. Regression analyses showed no significant linear or quadratic associations between any of the echocardiographic functions and the cognitive function measures. None of the echocardiographic measures as representative of cardiac function was correlated with memory or executive function in this group of community-dwelling older cardiac patients. These findings contrast with those of previous studies. © 2017 Japanese Psychogeriatric Society.

Cardiac function and cognition in older community-dwelling cardiac patients

NARCIS (Netherlands)

Eggermont, Laura H.P.; Aly, Mohamed F.A.; Vuijk, Pieter J.; de Boer, Karin; Kamp, Otto; van Rossum, Albert C.; Scherder, Erik J.A.

2017-01-01

Background: Cognitive deficits have been reported in older cardiac patients. An underlying mechanism for these findings may be reduced cardiac function. The relationship between cardiac function as represented by different echocardiographic measures and different cognitive function domains in older

Detecting early cardiac dysfunction with radionuclide cardiac blood-pool imaging

International Nuclear Information System (INIS)

Wu Kegui; Chen Daguang; Lin Haoxue

1992-01-01

Cardiac function was measured by radionuclide cardiac blood-pool imaging in 15 normal persons, 19 cases of hypertension, 32 cases of coronary heart disease, 35 cases of coronary heart disease combined with hypertension and 44 cases of myocardial infarction. Significant differences have been found in indices of cardiac function between normal subjects and patients with coronary heart disease and coronary heart disease combined with hypertension, even though the patients were without any clinical sin of cardiac failure. Lowered regional EF and decreased ventricular was motion were found in 38.8% of patients, while 65.7%of patients revealed marked abnormality in MFR. The results indicate that latent cardiac dysfunction is common in patients with coronary heart disease. The earliest change is diastolic function abnormalities

Cardiac Function Remains Impaired Despite Reversible Cardiac Remodeling after Acute Experimental Viral Myocarditis

Directory of Open Access Journals (Sweden)

Peter Moritz Becher

2017-01-01

Full Text Available Background. Infection with Coxsackievirus B3 induces myocarditis. We aimed to compare the acute and chronic phases of viral myocarditis to identify the immediate effects of cardiac inflammation as well as the long-term effects after resolved inflammation on cardiac fibrosis and consequently on cardiac function. Material and Methods. We infected C57BL/6J mice with Coxsackievirus B3 and determined the hemodynamic function 7 as well as 28 days after infection. Subsequently, we analyzed viral burden and viral replication in the cardiac tissue as well as the expression of cytokines and matrix proteins. Furthermore, cardiac fibroblasts were infected with virus to investigate if viral infection alone induces profibrotic signaling. Results. Severe cardiac inflammation was determined and cardiac fibrosis was consistently colocalized with inflammation during the acute phase of myocarditis. Declined cardiac inflammation but no significantly improved hemodynamic function was observed 28 days after infection. Interestingly, cardiac fibrosis declined to basal levels as well. Both cardiac inflammation and fibrosis were reversible, whereas the hemodynamic function remains impaired after healed viral myocarditis in C57BL/6J mice.

Current role of cardiac and extra-cardiac pathologies in clinically indicated cardiac computed tomography with emphasis on status before pulmonary vein isolation

Energy Technology Data Exchange (ETDEWEB)

Sohns, J.M.; Lotz, J. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; German Center for Cardiovascular Research (DZHK), Goettingen (Germany); Menke, J.; Staab, W.; Fasshauer, M.; Kowallick, J.T.; Zwaka, P.A.; Schwarz, A. [Goettingen University Medical Center (Germany). Inst. for Diagnostic and Interventional Radiology; Spiro, J. [Koeln University Hospital (Germany). Radiology; Bergau, L.; Unterberg-Buchwald, C. [Goettingen University Medical Center (Germany). Cardiology and Pneumology

2014-09-15

Purpose: The aim of this study was to assess the incidence of cardiac and significant extra-cardiac findings in clinical computed tomography of the heart in patients with atrial fibrillation before pulmonary vein isolation (PVI). Materials and Methods: 224 patients (64 ± 10 years; male 63%) with atrial fibrillation were examined by cardiac 64-slice multidetector CT before PVI. Extra-cardiac findings were classified as 'significant' if they were recommended to additional diagnostics or therapy, and otherwise as 'non-significant'. Additionally, cardiac findings were documented in detail. Results: A total of 724 cardiac findings were identified in 203 patients (91% of patients). Additionally, a total of 619 extra-cardiac findings were identified in 179 patients (80% of patients). Among these extra-cardiac findings 196 (32%) were 'significant', and 423 (68%) were 'non-significant'. In 2 patients (1%) a previously unknown malignancy was detected (esophageal cancer and lung cancer, local stage, no metastasis). 203 additional imaging diagnostics followed to clarify the 'significant' findings (124 additional CT, costs 38,314.69 US dollars). Overall, there were 3.2 cardiac and 2.8 extra-cardiac findings per patient. Extra-cardiac findings appear significantly more frequently in patients over 60 years old, in smokers and in patients with a history of cardiac findings (p < 0.05). Conclusion: Cardiac CT scans before PVI should be screened for extracardiac incidental findings that could have important clinical implications for each patient. (orig.)

Epidemiology and Outcomes After In-Hospital Cardiac Arrest After Pediatric Cardiac Surgery

Science.gov (United States)

Gupta, Punkaj; Jacobs, Jeffrey P.; Pasquali, Sara K.; Hill, Kevin D.; Gaynor, J. William; O’Brien, Sean M.; He, Max; Sheng, Shubin; Schexnayder, Stephen M.; Berg, Robert A.; Nadkarni, Vinay M.; Imamura, Michiaki; Jacobs, Marshall L.

2014-01-01

Background Multicenter data regarding cardiac arrest in children undergoing heart operations are limited. We describe epidemiology and outcomes associated with postoperative cardiac arrest in a large multiinstitutional cohort. Methods Patients younger than 18 years in the Society of Thoracic Surgeons Congenital Heart Surgery Database (2007 through 2012) were included. Patient factors, operative characteristics, and outcomes were described for patients with and without postoperative cardiac arrest. Multivariable models were used to evaluate the association of center volume with cardiac arrest rate and mortality after cardiac arrest, adjusting for patient and procedural factors. Results Of 70,270 patients (97 centers), 1,843 (2.6%) had postoperative cardiac arrest. Younger age, lower weight, and presence of preoperative morbidities (all p < 0.0001) were associated with cardiac arrest. Arrest rate increased with procedural complexity across common benchmark operations, ranging from 0.7% (ventricular septal defect repair) to 12.7% (Norwood operation). Cardiac arrest was associated with significant mortality risk across procedures, ranging from 15.4% to 62.3% (all p < 0.0001). In multivariable analysis, arrest rate was not associated with center volume (odds ratio, 1.06; 95% confidence interval, 0.71 to 1.57 in low- versus high-volume centers). However, mortality after cardiac arrest was higher in low-volume centers (odds ratio, 2.00; 95% confidence interval, 1.52 to 2.63). This association was present for both high- and low-complexity operations. Conclusions Cardiac arrest carries a significant mortality risk across the stratum of procedural complexity. Although arrest rates are not associated with center volume, lower-volume centers have increased mortality after cardiac arrest. Further study of mechanisms to prevent cardiac arrest and to reduce mortality in those with an arrest is warranted. PMID:25443018

Disruption of myoblast alignment by highly motile rhabdomyosarcoma cell in tissue structure.

Science.gov (United States)

Li, Menglu; Nagamori, Eiji; Kino-Oka, Masahiro

2017-02-01

Rhabdomyosarcoma (RMS) is a highly malignant tumor type of skeletal muscle origin, hallmarked by local invasion. Interaction between invasive tumor cells and normal cells plays a major role in tumor invasion and metastasis. Culturing tumor cells in a three-dimensional (3D) model can translate tumor malignancy relevant cell-cell interaction. To mimic tumor heterogeneity in vitro, a co-culture system consisting of a malignant embryonal rhabdomyosarcoma (ERMS) cell line RD and a normal human skeletal muscle myoblast (HSMM) cell line was established by cell sheet technology. Various ratios of RDs to HSMMs were employed to understand the quantitative effect on intercellular interactions. Disruption of sheet structure was observed in heterogeneous cell sheets having a low ratio of RDs to HSMMs, whereas homogeneous HSMM or RD sheets maintained intact structure. Deeper exploration of dynamic tumor cell behavior inside HSMM sheets revealed that HSMM cell alignment was disrupted by highly motile RDs. This study demonstrated that RMS cells are capable of compromising their surrounding environment through induced decay of HSMMs alignment in a cell-based 3D system. This suggests that muscle disruption might be a major consequence of RMS cell invasion into muscles, which could be a promising target to preventing tumor invasion. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

First intron of nestin gene regulates its expression during C2C12 myoblast ifferentiation

Institute of Scientific and Technical Information of China (English)

Hua Zhong; Zhigang Jin; Yongfeng Chen; Ting Zhang; Wei Bian; Xing Cui; Naihe Jing

2008-01-01

Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China Nestin is an intermediate filament protein expressed in neural progenitor cells and in developing skeletal muscle. Nestin has been widely used as a neural progenitor cell marker. It is well established that the specific expression of the nestin gene in neural progenitor cells is conferred by the neural-specific enhancer located in the second intron of the nestin gene. However, the transcriptional mechanism of nestin expression in developing muscle is still unclear. In this study, we identified a muscle cell-specific enhancer in the first intron of mouse nestin gene in mouse myoblast C2C12 cells.We localized the core enhancer activity to the 291-661 region of the first intron, and showed that the two E-boxes in the core enhancer region were important for enhancer activity in differentiating C2C12 cells. We also showed that MyoD protein was involved in the regulation of nestin expression in the myogenic differentiation of C2C12 cells.

Stimulating endogenous cardiac regeneration

Directory of Open Access Journals (Sweden)

Amanda eFinan

2015-09-01

Full Text Available The healthy adult heart has a low turnover of cardiac myocytes. The renewal capacity, however, is augmented after cardiac injury. Participants in cardiac regeneration include cardiac myocytes themselves, cardiac progenitor cells, and peripheral stem cells, particularly from the bone marrow compartment. Cardiac progenitor cells and bone marrow stem cells are augmented after cardiac injury, migrate to the myocardium, and support regeneration. Depletion studies of these populations have demonstrated their necessary role in cardiac repair. However, the potential of these cells to completely regenerate the heart is limited. Efforts are now being focused on ways to augment these natural pathways to improve cardiac healing, primarily after ischemic injury but in other cardiac pathologies as well. Cell and gene therapy or pharmacological interventions are proposed mechanisms. Cell therapy has demonstrated modest results and has passed into clinical trials. However, the beneficial effects of cell therapy have primarily been their ability to produce paracrine effects on the cardiac tissue and recruit endogenous stem cell populations as opposed to direct cardiac regeneration. Gene therapy efforts have focused on prolonging or reactivating natural signaling pathways. Positive results have been demonstrated to activate the endogenous stem cell populations and are currently being tested in clinical trials. A potential new avenue may be to refine pharmacological treatments that are currently in place in the clinic. Evidence is mounting that drugs such as statins or beta blockers may alter endogenous stem cell activity. Understanding the effects of these drugs on stem cell repair while keeping in mind their primary function may strike a balance in myocardial healing. To maximize endogenous cardiac regeneration,a combination of these approaches couldameliorate the overall repair process to incorporate the participation ofmultiple cell players.

Perturbations of NAD+ salvage systems impact mitochondrial function and energy homeostasis in mouse myoblasts and intact skeletal muscle

DEFF Research Database (Denmark)

Andersen, Marianne Agerholm; Dall, Morten; Jensen, Benjamin Anderschou Holbech

2018-01-01

Nicotinamide adenine dinucleotide (NAD+) can be synthesized by nicotinamide phosphoribosyltransferase (NAMPT). We aimed to determine the role of NAMPT for maintaining NAD+ levels, mitochondrial function, and metabolic homeostasis in skeletal muscle cells. We generated stable Nampt knockdown (sh......Nampt KD) C2C12 cells using a shRNA lentiviral approach. Moreover, we applied gene electrotransfer to express cre recombinase in tibialis anterior muscle of floxed Nampt mice. In shNampt KD C2C12 myoblasts, Nampt and NAD+ levels were reduced by 70% and 50%, respectively, and maximal respiratory capacity...... was reduced by 25%. Moreover, anaerobic glycolytic flux increased by 55% and 2-deoxyglucose uptake increased by 25% in shNampt KD cells. Treatment with the NAD+ precursor nicotinamide riboside restored NAD+ levels in shNampt cells and increased maximal respiratory capacity by 18% and 32% in control and sh...

Cardiac rehabilitation

Science.gov (United States)

... rehab; Heart failure - cardiac rehab References Anderson L, Taylor RS. Cardiac rehabilitation for people with heart disease: ... of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, WA. Also reviewed ...

Defining the Intrinsic Cardiac Risks of Operations to Improve Preoperative Cardiac Risk Assessments.

Science.gov (United States)

Liu, Jason B; Liu, Yaoming; Cohen, Mark E; Ko, Clifford Y; Sweitzer, Bobbie J

2018-02-01

Current preoperative cardiac risk stratification practices group operations into broad categories, which might inadequately consider the intrinsic cardiac risks of individual operations. We sought to define the intrinsic cardiac risks of individual operations and to demonstrate how grouping operations might lead to imprecise estimates of perioperative cardiac risk. Elective operations (based on Common Procedural Terminology codes) performed from January 1, 2010 to December 31, 2015 at hospitals participating in the American College of Surgeons National Surgical Quality Improvement Program were studied. A composite measure of perioperative adverse cardiac events was defined as either cardiac arrest requiring cardiopulmonary resuscitation or acute myocardial infarction. Operations' intrinsic cardiac risks were derived from mixed-effects models while controlling for patient mix. Resultant risks were sorted into low-, intermediate-, and high-risk categories, and the most commonly performed operations within each category were identified. Intrinsic operative risks were also examined using a representative grouping of operations to portray within-group variation. Sixty-six low, 30 intermediate, and 106 high intrinsic cardiac risk operations were identified. Excisional breast biopsy had the lowest intrinsic cardiac risk (overall rate, 0.01%; odds ratio, 0.11; 95% CI, 0.02 to 0.25) relative to the average, whereas aorto-bifemoral bypass grafting had the highest (overall rate, 4.1%; odds ratio, 6.61; 95% CI, 5.54 to 7.90). There was wide variation in the intrinsic cardiac risks of operations within the representative grouping (median odds ratio, 1.40; interquartile range, 0.88 to 2.17). A continuum of intrinsic cardiac risk exists among operations. Grouping operations into broad categories inadequately accounts for the intrinsic cardiac risk of individual operations.

Mathematical cardiac electrophysiology

CERN Document Server

Colli Franzone, Piero; Scacchi, Simone

2014-01-01

This book covers the main mathematical and numerical models in computational electrocardiology, ranging from microscopic membrane models of cardiac ionic channels to macroscopic bidomain, monodomain, eikonal models and cardiac source representations. These advanced multiscale and nonlinear models describe the cardiac bioelectrical activity from the cell level to the body surface and are employed in both the direct and inverse problems of electrocardiology. The book also covers advanced numerical techniques needed to efficiently carry out large-scale cardiac simulations, including time and space discretizations, decoupling and operator splitting techniques, parallel finite element solvers. These techniques are employed in 3D cardiac simulations illustrating the excitation mechanisms, the anisotropic effects on excitation and repolarization wavefronts, the morphology of electrograms in normal and pathological tissue and some reentry phenomena. The overall aim of the book is to present rigorously the mathematica...

Association between dental caries and out-of-hospital cardiac arrests of cardiac origin in Japan.

Science.gov (United States)

Suematsu, Yasunori; Miura, Shin-Ichiro; Zhang, Bo; Uehara, Yoshinari; Ogawa, Masahiro; Yonemoto, Naohiro; Nonogi, Hiroshi; Nagao, Ken; Kimura, Takeshi; Saku, Keijiro

2016-04-01

Oral infection contributes to atherosclerosis and coronary heart disease. We hypothesized that dental caries may be associated with out-of-hospital cardiac arrests (OHCA) of cardiac origin, but not non-cardiac origin. We compared the age-adjusted incidence of OHCA (785,591 cases of OHCA: 55.4% of cardiac origin and 44.6% of non-cardiac origin) to the age-adjusted prevalence of dental caries between 2005 and 2011 in the 47 prefectures of Japan. In both the total population and males over 65 years, the number of cases of dental caries was significantly associated with the number of OHCA of total and cardiac origin from 2005 to 2011, but not those of non-cardiac origin. In the total population, the age-adjusted prevalence of dental caries was not significantly associated with the age-adjusted incidence of OHCA (total OHCA: r correlation coefficient=0.22, p=0.14; OHCA of cardiac origin: r=0.25, p=0.09; OHCA of non-cardiac origin: r=-0.002, p=0.99). Among male patients over 65 years, the age-adjusted prevalence of dental caries was significantly associated with OHCA of total and cardiac origin, but not non-cardiac origin (total OHCA: r=0.47, p<0.001; OHCA of cardiac origin: r=0.37, p=0.01; OHCA of non-cardiac origin: r=0.28, p=0.054). While oral hygiene is important in all age groups, it may be particularly associated with OHCAs of cardiac origin in males over 65 years. Copyright © 2015. Published by Elsevier Ltd.

Exercise-related cardiac arrest in cardiac rehabilitation - The ...

African Journals Online (AJOL)

Prescribed physical activity plays a major role in the rehabilitation of patients with coronary artery disease, and as with any other form of treatment its benefits must be weighed against its possible risks. This study attempted to establish the safety of cardiac rehabilitation as a medical intervention at the Johannesburg Cardiac ...

Sudden cardiac death

Directory of Open Access Journals (Sweden)

Neeraj Parakh

2015-01-01

Full Text Available Sudden cardiac death is one of the most common cause of mortality worldwide. Despite significant advances in the medical science, there is little improvement in the sudden cardiac death related mortality. Coronary artery disease is the most common etiology behind sudden cardiac death, in the above 40 years population. Even in the apparently healthy population, there is a small percentage of patients dying from sudden cardiac death. Given the large denominator, this small percentage contributes to the largest burden of sudden cardiac death. Identification of this at risk group among the apparently healthy individual is a great challenge for the medical fraternity. This article looks into the causes and methods of preventing SCD and at some of the Indian data. Details of Brugada syndrome, Long QT syndrome, Genetics of SCD are discussed. Recent guidelines on many of these causes are summarised.

Bioenergetic Profile Experiment using C2C12 Myoblast Cells

Science.gov (United States)

Nicholls, David G.; Darley-Usmar, Victor M.; Wu, Min; Jensen, Per Bo; Rogers, George W.; Ferrick, David A.

2010-01-01

The ability to measure cellular metabolism and understand mitochondrial dysfunction, has enabled scientists worldwide to advance their research in understanding the role of mitochondrial function in obesity, diabetes, aging, cancer, cardiovascular function and safety toxicity. Cellular metabolism is the process of substrate uptake, such as oxygen, glucose, fatty acids, and glutamine, and subsequent energy conversion through a series of enzymatically controlled oxidation and reduction reactions. These intracellular biochemical reactions result in the production of ATP, the release of heat and chemical byproducts, such as lactate and CO2 into the extracellular environment. Valuable insight into the physiological state of cells, and the alteration of the state of those cells, can be gained through measuring the rate of oxygen consumed by the cells, an indicator of mitochondrial respiration - the Oxygen Consumption Rate - or OCR. Cells also generate ATP through glycolysis, i.e.: the conversion of glucose to lactate, independent of oxygen. In cultured wells, lactate is the primary source of protons. Measuring the lactic acid produced indirectly via protons released into the extracellular medium surrounding the cells, which causes acidification of the medium provides the Extra-Cellular Acidification Rate - or ECAR. In this experiment, C2C12 myoblast cells are seeded at a given density in Seahorse cell culture plates. The basal oxygen consumption (OCR) and extracellular acidification (ECAR) rates are measured to establish baseline rates. The cells are then metabolically perturbed by three additions of different compounds (in succession) that shift the bioenergetic profile of the cell. This assay is derived from a classic experiment to assess mitochondria and serves as a framework with which to build more complex experiments aimed at understanding both physiologic and pathophysiologic function of mitochondria and to predict the ability of cells to respond to stress and

Recurrent late cardiac tamponade following cardiac surgery : a deceiving and potentially lethal complication

NARCIS (Netherlands)

Harskamp, Ralf E.; Meuzelaar, Jacobus J.

2010-01-01

Background - Cardiac tamponade, characterized by inflow obstruction of the heart chambers by extracardiac compression, is a potentially lethal complication following cardiac surgery. Case report - We present a case of recurrent cardiac tamponade following valve surgery. At first presentation,

Small cardiac lesions: fibrosis of papillary muscles and focal cardiac myocytolysis

Energy Technology Data Exchange (ETDEWEB)

Steer, A [Hijiyanna Park, Hiroshima JP; Nakashima, N; Kawashima, T; Lee, K K; Danzig, M D; Robertson, T L; Dock, D S

1977-11-01

Three types of small cardiac lesions were described and illustrated: (1) focal type of papillary muscle fibrosis, evidently a healed infarct of the papillary muscle present in 13% of the autopsies, is a histologically characteristic lesion associated with coronary artery disease and healed myocardial infarction; (2) diffuse type of papillary muscle fibrosis, probably an aging change present in almost half of the autopsies, is associated with sclerosis of the arteries in the papillary muscle, is identifiable histologically; and apparently is not associated with any cardiac abnormality; and (3) focal cardiac myocytolysis, a unique histologic lesion, usually multifocal without predilection for any area of the heart, is associated with ischemic heart disease, death due to cancer complicated by non-bacterial thrombotic endocarditis and microthrombi in small cardiac arteries as well as with other diseases. Differentiation of the 2 types of papillary muscle fibrosis is important in the study of papillary muscle and mitral valve dysfunction. Focal cardiac myocytolysis may contribute to the fatal extension of myocardial infarcts.

Small cardiac lesions: fibrosis of papillary muscles and focal cardiac myocytolysis

Energy Technology Data Exchange (ETDEWEB)

Steer, A; Nakashima, T; Kawashima, T; Lee, K K; Danzig, M D; Robertson, T L; Dock, D S

1977-11-01

Three types of small cardiac lesions were described and illustrated: (1) focal type of papillary muscle fibrosis, evidently a healed infarct of the papillary muscle present in 13% of the autopsies, is a histologically characteristic lesion associated with coronary artery disease and healed myocardial infarction, (2) diffuse type of papillary muscle fibrosis, probably an aging change present in almost half of the autopsies, is associated with sclerosis of the arteries in the papillary muscle, is identifiable histologically, and apparently is not associated with any cardiac abnormality, and (3) focal cardiac myochtolysis, a unique histologic lesion, usually multifocal without predilection for any area of the heart, is associated with ischemic heart disease, death due to cancer complicated by nonbacterial thrombotic endocarditis and microthrombi in small cardiac arteries as well as with other diseases. Differentiation of the 2 types of papillary muscle fibrosis is important in the study of papillary muscle and mitral valve dysfunction. Focal cardiac myocytolysis may contribute to the fatal extension of myocardial infarcts.

Recurrent late cardiac tamponade following cardiac surgery: a deceiving and potentially lethal complication

NARCIS (Netherlands)

Harskamp, Ralf E.; Meuzelaar, Jacobus J.

2010-01-01

Cardiac tamponade, characterized by inflow obstruction of the heart chambers by extracardiac compression, is a potentially lethal complication following cardiac surgery. We present a case of recurrent cardiac tamponade following valve surgery. At first presentation, diagnosis was delayed because of

Diffuse infiltrative cardiac tuberculosis

International Nuclear Information System (INIS)

Gulati, Gurpreet S; Kothari, Shyam S

2011-01-01

We present the cardiac magnetic resonance images of an unusual form of cardiac tuberculosis. Nodular masses in a sheet-like distribution were seen to infiltrate the outer myocardium and pericardium along most of the cardiac chambers. The lesions showed significant resolution on antitubercular therapy

Assessment of cardiac risk before non-cardiac surgery: brain natriuretic peptide in 1590 patients.

Science.gov (United States)

Dernellis, J; Panaretou, M

2006-11-01

To evaluate the predictive value of brain natriuretic peptide (BNP) for assessment of cardiac risk before non-cardiac surgery. Consecutively treated patients (947 men, 643 women) whose BNP was measured before non-cardiac surgery were studied. Clinical and ECG variables were evaluated to identify predictors of postoperative cardiac events. Events occurred in 6% of patients: 21 cardiac deaths, 20 non-fatal myocardial infarctions, 41 episodes of pulmonary oedema and 14 patients with ventricular tachycardia. All of these patients had raised plasma BNP concentrations (best cut-off point 189 pg/ml). The only independent predictor of postoperative events was BNP (odds ratio 34.52, 95% confidence interval (CI) 17.08 to 68.62, p 300 pg/ml); postoperative event rates were 0%, 5%, 12% and 81%, respectively. In this population of patients evaluated before non-cardiac surgery, BNP is an independent predictor of postoperative cardiac events. BNP > 189 pg/ml identified patients at highest risk.

123I-MIBG imaging detects cardiac involvement and predicts cardiac events in Churg-Strauss syndrome

International Nuclear Information System (INIS)

Horiguchi, Yoriko; Morita, Yukiko; Tsurikisawa, Naomi; Akiyama, Kazuo

2011-01-01

In Churg-Strauss syndrome (CSS) it is important to detect cardiac involvement, which predicts poor prognosis. This study evaluated whether 123 I-metaiodobenzylguanidine (MIBG) scintigraphy could detect cardiac damage and predict cardiac events in CSS. 123 I-MIBG scintigraphy was performed in 28 patients with CSS, 12 of whom had cardiac involvement. The early and delayed heart to mediastinum ratio (early H/M and delayed H/M) and washout rate were calculated by using 123 I-MIBG scintigraphy and compared with those in control subjects. Early H/M and delayed H/M were significantly lower and the washout rate was significantly higher in patients with cardiac involvement than in those without and in controls (early H/M, p = 0.0024, p = 0.0001; delayed H/M, p = 0.0002, p = 0.0001; washout rate, p = 0.0012, p = 0.0052 vs those without and vs controls, respectively). Accuracy for detecting cardiac involvement was 86% for delayed H/M and washout rate and 79% for early H/M and B-type natriuretic peptide (BNP). Kaplan-Meier analysis showed significantly lower cardiac event-free rates in patients with early H/M ≤ 2.18 and BNP > 21.8 pg/ml than those with early H/M > 2.18 and BNP ≤ 21.8 pg/ml (log-rank test p = 0.006). Cardiac sympathetic nerve function was damaged in CSS patients with cardiac involvement. 123 I-MIBG scintigraphy was useful in detecting cardiac involvement and in predicting cardiac events. (orig.)

CARDIAC LYMPHOMA IN DOG

Directory of Open Access Journals (Sweden)

G. D. Cruz

2016-11-01

Full Text Available Lymphoma is a lymphoid tumor that originates in hematopoietic organs such as lymph node, spleen or liver. In dogs, the overall prevalence of cardiac tumors was estimated to be only 0.19% based on the results of the survey of a large database, and lymphomas accounts for approximately 2% of all cardiac tumors. In general, the involvement of the myocardium is rarely described in canine lymphoma. Currently, there is no evidence of a viral association with primary cardiac lymphoma in dogs, but other types of immunosuppression may contribute to abnormal events, such as involvement primary cardiac. The aim of this study was to analyze a case of sudden death of a bitch, SRD, aged 10, who had the final diagnosis of cardiac lymphoma.

Cardiac cone-beam CT

International Nuclear Information System (INIS)

Manzke, Robert

2005-01-01

This doctoral thesis addresses imaging of the heart with retrospectively gated helical cone-beam computed tomography (CT). A thorough review of the CT reconstruction literature is presented in combination with a historic overview of cardiac CT imaging and a brief introduction to other cardiac imaging modalities. The thesis includes a comprehensive chapter about the theory of CT reconstruction, familiarizing the reader with the problem of cone-beam reconstruction. The anatomic and dynamic properties of the heart are outlined and techniques to derive the gating information are reviewed. With the extended cardiac reconstruction (ECR) framework, a new approach is presented for the heart-rate-adaptive gated helical cardiac cone-beam CT reconstruction. Reconstruction assessment criteria such as the temporal resolution, the homogeneity in terms of the cardiac phase, and the smoothness at cycle-to-cycle transitions are developed. Several reconstruction optimization approaches are described: An approach for the heart-rate-adaptive optimization of the temporal resolution is presented. Streak artifacts at cycle-to-cycle transitions can be minimized by using an improved cardiac weighting scheme. The optimal quiescent cardiac phase for the reconstruction can be determined automatically with the motion map technique. Results for all optimization procedures applied to ECR are presented and discussed based on patient and phantom data. The ECR algorithm is analyzed for larger detector arrays of future cone-beam systems throughout an extensive simulation study based on a four-dimensional cardiac CT phantom. The results of the scientific work are summarized and an outlook proposing future directions is given. The presented thesis is available for public download at www.cardiac-ct.net

Polymer microfiber meshes facilitate cardiac differentiation of c-kit{sup +} human cardiac stem cells

Energy Technology Data Exchange (ETDEWEB)

Kan, Lijuan [Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (United States); Thayer, Patrick [Department of Chemical Engineering, School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA (United States); Fan, Huimin [Research Institute of Heart Failure, Shanghai East Hospital of Tongji University, Shanghai (China); Ledford, Benjamin; Chen, Miao [Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (United States); Goldstein, Aaron [Department of Chemical Engineering, School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA (United States); Cao, Guohua [School of Biomedical Engineering and Sciences, Virginia Tech, Blacksburg, VA (United States); He, Jia-Qiang, E-mail: jiahe@vt.edu [Department of Biomedical Sciences and Pathobiology, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, VA (United States)

2016-09-10

Electrospun microfiber meshes have been shown to support the proliferation and differentiation of many types of stem cells, but the phenotypic fate of c-kit{sup +} human cardiac stem cells (hCSCs) have not been explored. To this end, we utilized thin (~5 µm) elastomeric meshes consisting of aligned 1.7 µm diameter poly (ester-urethane urea) microfibers as substrates to examine their effect on hCSC viability, morphology, proliferation, and differentiation relative to cells cultured on tissue culture polystyrene (TCPS). The results showed that cells on microfiber meshes displayed an elongated morphology aligned in the direction of fiber orientation, lower proliferation rates, but increased expressions of genes and proteins majorly associated with cardiomyocyte phenotype. The early (NK2 homeobox 5, Nkx2.5) and late (cardiac troponin I, cTnI) cardiomyocyte genes were significantly increased on meshes (Nkx=2.5 56.2±13.0, cTnl=2.9±0.56,) over TCPS (Nkx2.5=4.2±0.9, cTnl=1.6±0.5, n=9, p<0.05 for both groups) after differentiation. In contrast, expressions of smooth muscle markers, Gata6 and myosin heavy chain (SM-MHC), were decreased on meshes. Immunocytochemical analysis with cardiac antibody exhibited the similar pattern of above cardiac differentiation. We conclude that aligned microfiber meshes are suitable for guiding cardiac differentiation of hCSCs and may facilitate stem cell-based therapies for treatment of cardiac diseases. - Highlights: • First study to characterize c-kit{sup +} human cardiac stem cells on microfiber meshes. • Microfiber meshes seem reducing cell proliferation, but no effect on cell viability. • Microfiber meshes facilitate the elongation of human cardiac stem cells in culture. • Cardiac but not smooth muscle differentiation were enhanced on microfiber meshes. • Microfiber meshes may be used as cardiac patches in cell-based cardiac therapy.

Comprehensive cardiac rehabilitation

DEFF Research Database (Denmark)

Kruse, Marie; Hochstrasser, Stefan; Zwisler, Ann-Dorthe O

2006-01-01

OBJECTIVES: The costs of comprehensive cardiac rehabilitation are established and compared to the corresponding costs of usual care. The effect on health-related quality of life is analyzed. METHODS: An unprecedented and very detailed cost assessment was carried out, as no guidelines existed...... and may be as high as euro 1.877. CONCLUSIONS: Comprehensive cardiac rehabilitation is more costly than usual care, and the higher costs are not outweighed by a quality of life gain. Comprehensive cardiac rehabilitation is, therefore, not cost-effective....

Autonomic cardiac innervation

Science.gov (United States)

Hasan, Wohaib

2013-01-01

Autonomic cardiac neurons have a common origin in the neural crest but undergo distinct developmental differentiation as they mature toward their adult phenotype. Progenitor cells respond to repulsive cues during migration, followed by differentiation cues from paracrine sources that promote neurochemistry and differentiation. When autonomic axons start to innervate cardiac tissue, neurotrophic factors from vascular tissue are essential for maintenance of neurons before they reach their targets, upon which target-derived trophic factors take over final maturation, synaptic strength and postnatal survival. Although target-derived neurotrophins have a central role to play in development, alternative sources of neurotrophins may also modulate innervation. Both developing and adult sympathetic neurons express proNGF, and adult parasympathetic cardiac ganglion neurons also synthesize and release NGF. The physiological function of these “non-classical” cardiac sources of neurotrophins remains to be determined, especially in relation to autocrine/paracrine sustenance during development.   Cardiac autonomic nerves are closely spatially associated in cardiac plexuses, ganglia and pacemaker regions and so are sensitive to release of neurotransmitter, neuropeptides and trophic factors from adjacent nerves. As such, in many cardiac pathologies, it is an imbalance within the two arms of the autonomic system that is critical for disease progression. Although this crosstalk between sympathetic and parasympathetic nerves has been well established for adult nerves, it is unclear whether a degree of paracrine regulation occurs across the autonomic limbs during development. Aberrant nerve remodeling is a common occurrence in many adult cardiovascular pathologies, and the mechanisms regulating outgrowth or denervation are disparate. However, autonomic neurons display considerable plasticity in this regard with neurotrophins and inflammatory cytokines having a central regulatory

Assessment of the antioxidant activity of an olive oil total polyphenolic fraction and hydroxytyrosol from a Greek Olea europea variety in endothelial cells and myoblasts.

Science.gov (United States)

Kouka, Paraskevi; Priftis, Alexandros; Stagos, Dimitrios; Angelis, Apostolis; Stathopoulos, Panagiotis; Xinos, Nikos; Skaltsounis, Alexios-Léandros; Mamoulakis, Charalampos; Tsatsakis, Aristides M; Spandidos, Demetrios A; Kouretas, Demetrios

2017-09-01

Olive oil (OO) constitutes the basis of the Mediterranean diet, and it seems that its biophenols, such as hydroxytyrosol (HT) may scavenge free radicals, attracting distinct attention due to their beneficial effects in many pathological conditions, such as cancer. To the best of our knowedge, this is the first study in which the functional properties of an OO total polyphenolic fraction (TPF) and pure HT were examined in order to determine their antioxidant effects at a cellular level in endothelial cells and myoblasts. The test compounds were isolated using a green gradient‑elution centrifugal partition chromatography‑based method that allows the isolation of large volumes of OO in a continuous extraction procedure and with extremely low solvent consumption. For the isolation of HT, a combination of two chromatographic techniques was used, which is effective for the recovery of pure compounds from complex natural extracts. Moreover, TPF and HT exhibited potent free radical scavenging activity in vitro. The cells were treated with non‑cytotoxic concentrations and their redox status [in terms of glutathione (GSH) and reactive oxygen species (ROS) levels] was assessed. TPF extract was less cytotoxic than HT, and the observed differences between the two cell lines used suggest a tissue‑specific activity. Finally, flow cytometric analysis revealed that both TPF and HT improved the redox status by increasing the levels of GSH, one of the most important antioxidant molecules, in both endothelial cells and myoblasts, while the ROS levels were not significantly affected.

Direct Cardiac Reprogramming: Advances in Cardiac Regeneration

Directory of Open Access Journals (Sweden)

Olivia Chen

2015-01-01

Full Text Available Heart disease is one of the lead causes of death worldwide. Many forms of heart disease, including myocardial infarction and pressure-loading cardiomyopathies, result in irreversible cardiomyocyte death. Activated fibroblasts respond to cardiac injury by forming scar tissue, but ultimately this response fails to restore cardiac function. Unfortunately, the human heart has little regenerative ability and long-term outcomes following acute coronary events often include chronic and end-stage heart failure. Building upon years of research aimed at restoring functional cardiomyocytes, recent advances have been made in the direct reprogramming of fibroblasts toward a cardiomyocyte cell fate both in vitro and in vivo. Several experiments show functional improvements in mouse models of myocardial infarction following in situ generation of cardiomyocyte-like cells from endogenous fibroblasts. Though many of these studies are in an early stage, this nascent technology holds promise for future applications in regenerative medicine. In this review, we discuss the history, progress, methods, challenges, and future directions of direct cardiac reprogramming.

Biomaterials for cardiac regeneration

CERN Document Server

Ruel, Marc

2015-01-01

This book offers readers a comprehensive biomaterials-based approach to achieving clinically successful, functionally integrated vasculogenesis and myogenesis in the heart. Coverage is multidisciplinary, including the role of extracellular matrices in cardiac development, whole-heart tissue engineering, imaging the mechanisms and effects of biomaterial-based cardiac regeneration, and autologous bioengineered heart valves. Bringing current knowledge together into a single volume, this book provides a compendium to students and new researchers in the field and constitutes a platform to allow for future developments and collaborative approaches in biomaterials-based regenerative medicine, even beyond cardiac applications. This book also: Provides a valuable overview of the engineering of biomaterials for cardiac regeneration, including coverage of combined biomaterials and stem cells, as well as extracellular matrices Presents readers with multidisciplinary coverage of biomaterials for cardiac repair, including ...

Metoclopramide-induced cardiac arrest

Directory of Open Access Journals (Sweden)

Martha M. Rumore

2011-11-01

Full Text Available The authors report a case of cardiac arrest in a patient receiving intravenous (IV metoclopramide and review the pertinent literature. A 62-year-old morbidly obese female admitted for a gastric sleeve procedure, developed cardiac arrest within one minute of receiving metoclopramide 10 mg via slow intravenous (IV injection. Bradycardia at 4 beats/min immediately appeared, progressing rapidly to asystole. Chest compressions restored vital function. Electrocardiogram (ECG revealed ST depression indicative of myocardial injury. Following intubation, the patient was transferred to the intensive care unit. Various cardiac dysrrhythmias including supraventricular tachycardia (SVT associated with hypertension and atrial fibrillation occurred. Following IV esmolol and metoprolol, the patient reverted to normal sinus rhythm. Repeat ECGs revealed ST depression resolution without pre-admission changes. Metoclopramide is a non-specific dopamine receptor antagonist. Seven cases of cardiac arrest and one of sinus arrest with metoclopramide were found in the literature. The metoclopramide prescribing information does not list precautions or adverse drug reactions (ADRs related to cardiac arrest. The reaction is not dose related but may relate to the IV administration route. Coronary artery disease was the sole risk factor identified. According to Naranjo, the association was possible. Other reports of cardiac arrest, severe bradycardia, and SVT were reviewed. In one case, five separate IV doses of 10 mg metoclopramide were immediately followed by asystole repeatedly. The mechanism(s underlying metoclopramide’s cardiac arrest-inducing effects is unknown. Structural similarities to procainamide may play a role. In view of eight previous cases of cardiac arrest from metoclopramide having been reported, further elucidation of this ADR and patient monitoring is needed. Our report should alert clinicians to monitor patients and remain diligent in surveillance and

Cardiac tumours: non invasive detection and assessment by gated cardiac blood pool radionuclide imaging

International Nuclear Information System (INIS)

Pitcher, D.; Wainwright, R.; Brennand-Roper, D.; Deverall, P.; Sowton, E.; Maisey, M.

1980-01-01

Four patients with cardiac tumours were investigated by gated cardiac blood pool radionuclide imaging and echocardiography. Contrast angiocardiography was performed in three of the cases. Two left atrial tumours were detected by all three techniques. In one of these cases echocardiography alone showed additional mitral valve stenosis, but isotope imaging indicated tumour size more accurately. A large septal mass was detected by all three methods. In this patient echocardiography showed evidence of left ventricular outflow obstruction, confirmed at cardiac catheterisation, but gated isotope imaging provided a more detailed assessment of the abnormal cardiac anatomy. In the fourth case gated isotope imaging detected a large right ventricular tumour which had not been identified by echocardiography. Gated cardiac blood pool isotope imaging is a complementary technique to echocardiography for the non-invasive detection and assessment of cardiac tumours. (author)

Pregnancy as a cardiac stress model

Science.gov (United States)

Chung, Eunhee; Leinwand, Leslie A.

2014-01-01

Cardiac hypertrophy occurs during pregnancy as a consequence of both volume overload and hormonal changes. Both pregnancy- and exercise-induced cardiac hypertrophy are generally thought to be similar and physiological. Despite the fact that there are shared transcriptional responses in both forms of cardiac adaptation, pregnancy results in a distinct signature of gene expression in the heart. In some cases, however, pregnancy can induce adverse cardiac events in previously healthy women without any known cardiovascular disease. Peripartum cardiomyopathy is the leading cause of non-obstetric mortality during pregnancy. To understand how pregnancy can cause heart disease, it is first important to understand cardiac adaptation during normal pregnancy. This review provides an overview of the cardiac consequences of pregnancy, including haemodynamic, functional, structural, and morphological adaptations, as well as molecular phenotypes. In addition, this review describes the signalling pathways responsible for pregnancy-induced cardiac hypertrophy and angiogenesis. We also compare and contrast cardiac adaptation in response to disease, exercise, and pregnancy. The comparisons of these settings of cardiac hypertrophy provide insight into pregnancy-associated cardiac adaptation. PMID:24448313

Human technology after cardiac epigenesis. Artificial heart versus cardiac transplantation.

Science.gov (United States)

Losman, J G

1977-09-24

Cardiovascular disease is the chief cause of death in technologically advanced countries and accounts for more than 50% of all deaths in the USA. For a patient with end-stage cardiac failure the only treatment presently available is organ replacement, either by transplantation or by the use of a mechanical heart. Transplantation has demonstrated its value: survival of more than 8 years and restoration of a normal quality of life to patients who were in end-stage cardiac decompensation. However, the prospect of routine clinical application of an artificial heart remains distant. The development of a totally implantable artificial heart still presents a series of challenging engineering problems with regard to strict constraints of size, weight, blood-material compatibility, adaptability of output to demand, efficiency and reliability of the power supply, and safety if nuclear fuel is used. The totally artificial heart is presently not an alternative to the cardiac allograft, but could provide short-term support for patients awaiting cardiac transplantation.

Marketing cardiac CT programs.

Science.gov (United States)

Scott, Jason

2010-01-01

There are two components of cardiac CT discussed in this article: coronary artery calcium scoring (CACS) and coronary computed tomography angiography (CCTA).The distinctive advantages of each CT examination are outlined. In order to ensure a successful cardiac CT program, it is imperative that imaging facilities market their cardiac CT practices effectively in order to gain a competitive advantage in this valuable market share. If patients receive quality care by competent individuals, they are more likely to recommend the facility's cardiac CT program. Satisfied patients will also be more willing to come back for any further testing.

Novel Endogenous, Insulin-Stimulated Akt2 Protein Interaction Partners in L6 Myoblasts.

Directory of Open Access Journals (Sweden)

Michael Caruso

Full Text Available Insulin resistance and Type 2 diabetes are marked by an aberrant response in the insulin signaling network. The phosphoinositide-dependent serine/threonine kinase, Akt2, plays a key role in insulin signaling and glucose uptake, most notably within skeletal muscle. Protein-protein interaction regulates the functional consequence of Akt2 and in turn, Akt2's role in glucose uptake. However, only few insulin-responsive Akt2 interaction partners have been identified in skeletal muscle cells. In the present work, rat L6 myoblasts, a widely used insulin sensitive skeletal muscle cell line, were used to examine endogenous, insulin-stimulated Akt2 protein interaction partners. Akt2 co-immunoprecipitation was coupled with 1D-SDS-PAGE and fractions were analyzed by HPLC-ESI-MS/MS to reveal Akt2 protein-protein interactions. The pull-down assay displayed specificity for the Akt2 isoform; Akt1 and Akt3 unique peptides were not detected. A total of 49 were detected with a significantly increased (47 or decreased (2 association with Akt2 following insulin administration (n = 4; p<0.05. Multiple pathways were identified for the novel Akt2 interaction partners, such as the EIF2 and ubiquitination pathways. These data suggest that multiple new endogenous proteins may associate with Akt2 under basal as well as insulin-stimulated conditions, providing further insight into the insulin signaling network. Data are available via ProteomeXchange with identifier PXD002557.

Cardiac CT and cardiac MRI - competitive or complementary for nuclear cardiology

International Nuclear Information System (INIS)

Moshage, W.

2004-01-01

In summary, cardiac computed tomography (CT) and cardiac magnetic resonance (MR) are two different technologies with distinct imaging properties that gain increasing importance in clinical cardiology. Even though images may look similar, the areas of application of CT and MR are quite different. Clinical applications of cardiac CT focus on on-invasive imaging of the coronary arteries. In this respect, the higher spatial resolution of cardiac CT constitutes a significant advantage as compared to MR and clinical results are superior. Clinical applications of cardiac MR, next to morphologic imaging of the heart, are most frequently found in the context of intra-and pericardial masses, complex congenital anomalies, and the assessment of left ventricular function (dobutamine) and perfusion (adenosine) under stress. The evaluation of the size and localization of myocardial necrosis, scars, and fibrosis gains increasing importance, for example in the workup of myocardial infarction, but also myocarditis and cardiomyopathies. In this respect, magnetic resonance imaging partly constitutes an alternative to nuclear medicine methods. Due to the lack of ionizing radiation and a relatively high spatial resolution, an increase of MR diagnostic procedures at the expense of nuclear medicine can be expected. (orig.)

Relationship between cardiac output and effective renal plasma flow in patients with cardiac disease

Energy Technology Data Exchange (ETDEWEB)

McGriffin, D; Tauxe, W N; Lewis, C; Karp, R; Mantle, J

1984-12-01

The relationship between effective renal plasma flow (ERPF) and cardiac output was examined in 46 patients (22 with congestive heart failure and 24 following cardiac surgical procedures) by simultaneously measuring the global ERPF by the single-injection method and cardiac output by the thermodilution method. Of the patients in the heart-failure group, 21 also had pulmonary artery end diastolic pressure (PAEDP) recorded at the same time. ERPF and cardiac output were found to be related by the regression equations: cardiac output = 2.08 + 0.0065 ERPF (r, 080), with a SE of estimate of 0.81 l/min. ERPF and PAEDP were related by the regression equation: PAEDP = 42.02 - 0.0675 ERPF (r, 0.86), with a SE of estimate of 5.5 mm Hg. ERPF may be a useful noninvasive method of estimating cardiac output if it is known that no intrinsic kidney disease is present, and if the error of 0.81 l/min (1 SE of estimate) is within the range of clinical usefulness. The error is principally attributable to the determination of cardiac output by the thermodilution method.

Hybrid options for treating cardiac disease.

Science.gov (United States)

Umakanthan, Ramanan; Leacche, Marzia; Zhao, David X; Gallion, Anna H; Mishra, Prabodh C; Byrne, John G

2011-01-01

The options for treating heart disease have greatly expanded during the course of the last 2 1/2 decades with the advent of hybrid technology. The hybrid option for treating cardiac disease implies using the technology of both interventional cardiology and cardiac surgery to treat cardiac disease. This rapidly developing technology has given rise to new and creative techniques to treat cardiac disease involving coronary artery disease, coronary artery disease and cardiac valve disease, and atrial fibrillation. It has also led to the establishment of new procedural suites called hybrid operating rooms that facilitate the integration of technologies of interventional cardiology catheterization laboratories with those of cardiac surgery operating rooms. The development of hybrid options for treating cardiac disease has also greatly augmented teamwork and collaboration between interventional cardiologists and cardiac surgeons. Copyright © 2011 Elsevier Inc. All rights reserved.

Cardiac CT

International Nuclear Information System (INIS)

Dewey, Marc

2011-01-01

Computed tomography of the heart has become a highly accurate diagnostic modality that is attracting increasing attention. This extensively illustrated book aims to assist the reader in integrating cardiac CT into daily clinical practice, while also reviewing its current technical status and applications. Clear guidance is provided on the performance and interpretation of imaging using the latest technology, which offers greater coverage, better spatial resolution, and faster imaging. The specific features of scanners from all four main vendors, including those that have only recently become available, are presented. Among the wide range of applications and issues to be discussed are coronary artery bypass grafts, stents, plaques, and anomalies, cardiac valves, congenital and acquired heart disease, and radiation exposure. Upcoming clinical uses of cardiac CT, such as plaque imaging and functional assessment, are also explored. (orig.)

Cardiac CT

Energy Technology Data Exchange (ETDEWEB)

Dewey, Marc [Charite - Universitaetsmedizin Berlin (Germany). Inst. fuer Radiologie

2011-07-01

Computed tomography of the heart has become a highly accurate diagnostic modality that is attracting increasing attention. This extensively illustrated book aims to assist the reader in integrating cardiac CT into daily clinical practice, while also reviewing its current technical status and applications. Clear guidance is provided on the performance and interpretation of imaging using the latest technology, which offers greater coverage, better spatial resolution, and faster imaging. The specific features of scanners from all four main vendors, including those that have only recently become available, are presented. Among the wide range of applications and issues to be discussed are coronary artery bypass grafts, stents, plaques, and anomalies, cardiac valves, congenital and acquired heart disease, and radiation exposure. Upcoming clinical uses of cardiac CT, such as plaque imaging and functional assessment, are also explored. (orig.)

Cellular cardiomyoplasty into infracted swine's hearts by retrograde infusion through the venous coronary sinus: An experimental study

International Nuclear Information System (INIS)

Prifti, Edvin; Di Lascio, Gabriella; Harmelin, Guy; Bani, Daniele; Briganti, Vittorio; Veshti, Altin; Bonacchi, Massimo

2016-01-01

Objectives: The aim was to create a model of myocardial infarction with a borderline myocardial impairment which would enable evaluation of the retrograde cellular cardiomyoplasty through the venous coronary sinus in a large animal model. Materials and methods: Fifteen (study group) and 10 juvenile farm pigs (control group) underwent distal left anterior descending artery ligation. One month later the study group animals underwent sternotomy and a murine myoblastic line C2-C12 was injected at a constant pressure of 30 mmHg, into the coronary sinus. Thirty days later all animals that survived from both groups underwent transthoracic echocardiography and 99Tc scintigraphy and were later euthanized and specimens were taken for microscopic evaluation. Results: Cardiac output decreased significantly after ligation (p < 0.001) and increased significantly after cardiomyoplasty (p < 0.001). In all animals, the surgical induction of myocardial infarction caused a marked decline in the echocardiographic values of cardiac function; however, the cardiac function and dimensions were significantly improved in the study group after cardiomyoplasty versus the control group. All animals undergoing cardiomyoplasty demonstrated a significant reduction of the perfusion deficit in the left anterior descending artery territory, instead such data remained unchanged in the control group. The histological examination demonstrated the engrafted myoblasts could be distinguished from the activated fibroblasts in the scar tissue because they never showed any signs of collagen secretion and fiber buildup. Conclusions: In conclusion, the venous retrograde delivery route through the coronary sinus is safe and effective, providing a significant improvement in function and viability.

Cellular cardiomyoplasty into infracted swine's hearts by retrograde infusion through the venous coronary sinus: An experimental study

Energy Technology Data Exchange (ETDEWEB)

Prifti, Edvin, E-mail: edvinprifti@hotmail.com [Division of Cardiac Surgery, University Hospital Center of Tirana (Albania); Di Lascio, Gabriella [Anesthesiology and Intensive Care Section, Department of Health Sciences, University of Florence, Florence (Italy); Harmelin, Guy [Cardiac Surgery, Department of Experimental and Clinical Medicine, University of Florence, Florence (Italy); Bani, Daniele [Research Unit of Histology & Embryology, Departments of Clinical & Experimental Medicine, University of Florence, Florence (Italy); Briganti, Vittorio [Unit of Nuclear Medicine, Careggi Hospital, Florence (Italy); Veshti, Altin [Division of Cardiac Surgery, University Hospital Center of Tirana (Albania); Bonacchi, Massimo [Cardiac Surgery, Department of Experimental and Clinical Medicine, University of Florence, Florence (Italy)

2016-06-15

Objectives: The aim was to create a model of myocardial infarction with a borderline myocardial impairment which would enable evaluation of the retrograde cellular cardiomyoplasty through the venous coronary sinus in a large animal model. Materials and methods: Fifteen (study group) and 10 juvenile farm pigs (control group) underwent distal left anterior descending artery ligation. One month later the study group animals underwent sternotomy and a murine myoblastic line C2-C12 was injected at a constant pressure of 30 mmHg, into the coronary sinus. Thirty days later all animals that survived from both groups underwent transthoracic echocardiography and 99Tc scintigraphy and were later euthanized and specimens were taken for microscopic evaluation. Results: Cardiac output decreased significantly after ligation (p < 0.001) and increased significantly after cardiomyoplasty (p < 0.001). In all animals, the surgical induction of myocardial infarction caused a marked decline in the echocardiographic values of cardiac function; however, the cardiac function and dimensions were significantly improved in the study group after cardiomyoplasty versus the control group. All animals undergoing cardiomyoplasty demonstrated a significant reduction of the perfusion deficit in the left anterior descending artery territory, instead such data remained unchanged in the control group. The histological examination demonstrated the engrafted myoblasts could be distinguished from the activated fibroblasts in the scar tissue because they never showed any signs of collagen secretion and fiber buildup. Conclusions: In conclusion, the venous retrograde delivery route through the coronary sinus is safe and effective, providing a significant improvement in function and viability.

Cardiac function in acute hypothyroidism

International Nuclear Information System (INIS)

Donaghue, K.; Hales, I.; Allwright, S.; Cooper, R.; Edwards, A.; Grant, S.; Morrow, A.; Wilmshurst, E.; Royal North Shore Hospital, Sydney

1985-01-01

It has been established that chronic hypothyroidism may affect cardiac function by several mechanisms. It is not known how long the patient has to be hypothyroid for cardiac involvement to develop. This study was undertaken to assess the effect of a short period of hypothyroidism (10 days) on cardiac function. Nine patients who had had total tyroidectomy, had received ablative radioiodine for thyroid cancer and were euthyroid on replacement therapy were studied while both euthyroid and hypothyroid. Cardiac assessment was performed by X-ray, ECG, echocardiography and gated blood-pool scans. After 10 days of hypothyroidisms, the left-ventricular ejection fraction failed to rise after exercise in 4 of the 9 patients studied, which was significant (P<0.002). No significant changes in cardiac size or function at rest were detected. This functional abnormality in the absence of any demonstrable change in cardiac size and the absence of pericardial effussion with normal basal function suggest that short periods of hypothyroidism may reduce cardiac reserve, mostly because of alterations in metabolic function. (orig.)

Nitrates for the prevention of cardiac morbidity and mortality in patients undergoing non-cardiac surgery.

Science.gov (United States)

Zhao, Na; Xu, Jin; Singh, Balwinder; Yu, Xuerong; Wu, Taixiang; Huang, Yuguang

2016-08-04

Cardiac complications are not uncommon in patients undergoing non-cardiac surgery, especially in patients with coronary artery disease (CAD) or at high risk of CAD. Perioperative cardiac complications can lead to mortality and morbidity, as well as higher costs for patient care. Nitrates, which are among the most commonly used cardiovascular drugs, perform the function of decreasing cardiac preload while improving cardiac blood perfusion. Sometimes, nitrates are administered to patients undergoing non-cardiac surgery to reduce the incidence of cardiac complications, especially for patients with CAD. However, their effects on patients' relevant outcomes remain controversial. • To assess effects of nitrates as compared with other interventions or placebo in reducing cardiac risk (such as death caused by cardiac factors, angina pectoris, acute myocardial infarction, acute heart failure and cardiac arrhythmia) in patients undergoing non-cardiac surgery.• To identify the influence of different routes and dosages of nitrates on patient outcomes. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and the Chinese BioMedical Database until June 2014. We also searched relevant conference abstracts of important anaesthesiology or cardiology scientific meetings, the database of ongoing trials and Google Scholar.We reran the search in January 2016. We added three potential new studies of interest to the list of 'Studies awaiting classification' and will incorporate them into our formal review findings for the review update. We included randomized controlled trials (RCTs) comparing nitrates versus no treatment, placebo or other pharmacological interventions in participants (15 years of age and older) undergoing non-cardiac surgery under any type of anaesthesia. We used standard methodological procedures as expected by Cochrane. Two review authors selected trials, extracted data from included studies and assessed risk of bias. We

Maternal cardiac metabolism in pregnancy

Science.gov (United States)

Liu, Laura X.; Arany, Zolt

2014-01-01

Pregnancy causes dramatic physiological changes in the expectant mother. The placenta, mostly foetal in origin, invades maternal uterine tissue early in pregnancy and unleashes a barrage of hormones and other factors. This foetal ‘invasion’ profoundly reprogrammes maternal physiology, affecting nearly every organ, including the heart and its metabolism. We briefly review here maternal systemic metabolic changes during pregnancy and cardiac metabolism in general. We then discuss changes in cardiac haemodynamic during pregnancy and review what is known about maternal cardiac metabolism during pregnancy. Lastly, we discuss cardiac diseases during pregnancy, including peripartum cardiomyopathy, and the potential contribution of aberrant cardiac metabolism to disease aetiology. PMID:24448314

{sup 123}I-MIBG imaging detects cardiac involvement and predicts cardiac events in Churg-Strauss syndrome

Energy Technology Data Exchange (ETDEWEB)

Horiguchi, Yoriko; Morita, Yukiko [National Hospital Organization Sagamihara National Hospital, Department of Cardiology, Sagamihara City, Kanagawa (Japan); Tsurikisawa, Naomi; Akiyama, Kazuo [National Hospital Organization Sagamihara National Hospital, Clinical Research Centre for Allergy and Rheumatology, Sagamihara City, Kanagawa (Japan)

2011-02-15

In Churg-Strauss syndrome (CSS) it is important to detect cardiac involvement, which predicts poor prognosis. This study evaluated whether {sup 123}I-metaiodobenzylguanidine (MIBG) scintigraphy could detect cardiac damage and predict cardiac events in CSS. {sup 123}I-MIBG scintigraphy was performed in 28 patients with CSS, 12 of whom had cardiac involvement. The early and delayed heart to mediastinum ratio (early H/M and delayed H/M) and washout rate were calculated by using {sup 123}I-MIBG scintigraphy and compared with those in control subjects. Early H/M and delayed H/M were significantly lower and the washout rate was significantly higher in patients with cardiac involvement than in those without and in controls (early H/M, p = 0.0024, p = 0.0001; delayed H/M, p = 0.0002, p = 0.0001; washout rate, p = 0.0012, p = 0.0052 vs those without and vs controls, respectively). Accuracy for detecting cardiac involvement was 86% for delayed H/M and washout rate and 79% for early H/M and B-type natriuretic peptide (BNP). Kaplan-Meier analysis showed significantly lower cardiac event-free rates in patients with early H/M {<=} 2.18 and BNP > 21.8 pg/ml than those with early H/M > 2.18 and BNP {<=} 21.8 pg/ml (log-rank test p = 0.006). Cardiac sympathetic nerve function was damaged in CSS patients with cardiac involvement. {sup 123}I-MIBG scintigraphy was useful in detecting cardiac involvement and in predicting cardiac events. (orig.)

Cardiac carcinoid: tricuspid delayed hyperenhancement on cardiac 64-slice multidetector CT and magnetic resonance imaging.

LENUS (Irish Health Repository)

Martos, R

2012-02-01

INTRODUCTION: Carcinoid heart disease is a rare condition in adults. Its diagnosis can be easily missed in a patient presenting to a primary care setting. We revised the advantages of using coronary multidetector computed tomography (MDCT) and cardiac magnetic resonance imaging (MRI) in diagnosing this condition. MATERIALS AND METHODS: We studied a 65-year-old patient with carcinoid heart disease and right heart failure using transthoracic Doppler-echocardiogram, cardiac MDCT and MRI. Cardiac echocardiogram revealed marked thickening and retraction of the tricuspid leaflets with dilated right atrium and ventricle. Cardiac MDCT and MRI demonstrated fixation and retraction of the tricuspid leaflets with delayed contrast hyperenhancement of the tricuspid annulus. CONCLUSION: This case demonstrates fascinating imaging findings of cardiac carcinoid disease and highlights the increasing utility of contrast-enhanced MRI and cardiac MDCT in the diagnosis of this interesting condition.

UCP3 Ablation Exacerbates High-Salt Induced Cardiac Hypertrophy and Cardiac Dysfunction

Directory of Open Access Journals (Sweden)

Hongmei Lang

2018-04-01

Full Text Available Background/Aims: Excessive salt intake and left ventricular hypertrophy (LVH are both critical for the development of hypertension and heart failure. The uncoupling protein 3 (UCP3 plays a cardio-protective role in early heart failure development. However, the potential role for UCP3 in salt intake and LVH is unclear. Methods: UCP3-/- and C57BL/6 mice were placed on either a normal-salt (NS, 0.5% or a high-salt (HS, 8% diet for 24 weeks. The cardiac function, endurance capacity, energy expenditure, and mitochondrial functional capacity were measured in each group. Results: Elevated blood pressure was only observed in HS-fed UCP3-/- mice. High salt induced cardiac hypertrophy and dysfunction were observed in both C57BL/6 and UCP3-/- mice. However, the cardiac lesions were more profound in HS-fed UCP3-/- mice. Furthermore, HS-fed UCP3-/-mice experienced more severe mitochondrial respiratory dysfunction compared with HS-fed C57BL/6 mice, represented by the decreased volume of oxygen consumption and heat production at the whole-body level. Conclusion: UCP3 protein was involved in the incidence of high-salt induced hypertension and the progression of cardiac dysfunction in the early stages of heart failure. UCP3 ablation exacerbated high-salt-induced cardiac hypertrophy and cardiac dysfunction.

Cardiac retransplantation is an efficacious therapy for primary cardiac allograft failure

Directory of Open Access Journals (Sweden)

Acker Michael A

2008-05-01

Full Text Available Abstract Background Although orthotopic heart transplantation has been an effective treatment for end-stage heart failure, the incidence of allograft failure has increased, necessitating treatment options. Cardiac retransplantation remains the only viable long-term solution for end-stage cardiac allograft failure. Given the limited number of available donor hearts, the long term results of this treatment option need to be evaluated. Methods 709 heart transplants were performed over a 20 year period at our institution. Repeat cardiac transplantation was performed in 15 patients (2.1%. A retrospective analysis was performed to determine the efficacy of cardiac retransplantation. Variables investigated included: 1 yr and 5 yr survival, length of hospitalization, post-operative complications, allograft failure, recipient and donor demographics, renal function, allograft ischemic time, UNOS listing status, blood group, allograft rejection, and hemodynamic function. Results Etiology of primary graft failure included transplant arteriopathy (n = 10, acute rejection (n = 3, hyperacute rejection (n = 1, and a post-transplant diagnosis of metastatic melanoma in the donor (n = 1. Mean age at retransplantation was 45.5 ± 9.7 years. 1 and 5 year survival for retransplantation were 86.6% and 71.4% respectively, as compared to 90.9% and 79.1% for primary transplantation. Mean ejection fraction was 67.3 ± 12.2% at a mean follow-up of 32.6 ± 18.5 mos post-retransplant; follow-up biopsy demonstrated either ISHLT grade 1A or 0 rejection (77.5 ± 95.7 mos post-transplant. Conclusion Cardiac retransplantation is an efficacious treatment strategy for cardiac allograft failure.

GRAF1 deficiency blunts sarcolemmal injury repair and exacerbates cardiac and skeletal muscle pathology in dystrophin-deficient mice.

Science.gov (United States)

Lenhart, Kaitlin C; O'Neill, Thomas J; Cheng, Zhaokang; Dee, Rachel; Demonbreun, Alexis R; Li, Jianbin; Xiao, Xiao; McNally, Elizabeth M; Mack, Christopher P; Taylor, Joan M

2015-01-01

The plasma membranes of striated muscle cells are particularly susceptible to rupture as they endure significant mechanical stress and strain during muscle contraction, and studies have shown that defects in membrane repair can contribute to the progression of muscular dystrophy. The synaptotagmin-related protein, dysferlin, has been implicated in mediating rapid membrane repair through its ability to direct intracellular vesicles to sites of membrane injury. However, further work is required to identify the precise molecular mechanisms that govern dysferlin targeting and membrane repair. We previously showed that the bin-amphiphysin-Rvs (BAR)-pleckstrin homology (PH) domain containing Rho-GAP GTPase regulator associated with focal adhesion kinase-1 (GRAF1) was dynamically recruited to the tips of fusing myoblasts wherein it promoted membrane merging by facilitating ferlin-dependent capturing of intracellular vesicles. Because acute membrane repair responses involve similar vesicle trafficking complexes/events and because our prior studies in GRAF1-deficient tadpoles revealed a putative role for GRAF1 in maintaining muscle membrane integrity, we postulated that GRAF1 might also play an important role in facilitating dysferlin-dependent plasma membrane repair. We used an in vitro laser-injury model to test whether GRAF1 was necessary for efficient muscle membrane repair. We also generated dystrophin/GRAF1 doubledeficient mice by breeding mdx mice with GRAF1 hypomorphic mice. Evans blue dye uptake and extensive morphometric analyses were used to assess sarcolemmal integrity and related pathologies in cardiac and skeletal muscles isolated from these mice. Herein, we show that GRAF1 is dynamically recruited to damaged skeletal and cardiac muscle plasma membranes and that GRAF1-depleted muscle cells have reduced membrane healing abilities. Moreover, we show that dystrophin depletion exacerbated muscle damage in GRAF1-deficient mice and that mice with dystrophin/GRAF1

Cardiac echinococcosis

Directory of Open Access Journals (Sweden)

Ivanović-Krstić Branislava A.

2002-01-01

Full Text Available Cardiac hydatid disease is rare. We report on an uncommon hydatid cyst localized in the right ventricular wall, right atrial wall tricuspid valve left atrium and pericard. A 33-year-old woman was treated for cough, fever and chest pain. Cardiac echocardiograpic examination revealed a round tumor (5.8 x 4 cm in the right ventricular free wall and two smaller cysts behind that tumor. There were cysts in right atrial wall and tricuspidal valve as well. Serologic tests for hydatidosis were positive. Computed tomography finding was consistent with diagnosis of hydatid cyst in lungs and right hylar part. Surgical treatment was rejected due to great risk of cardiac perforation. Medical treatment with albendazole was unsuccessful and the patient died due to systemic hydatid involvement of the lungs, liver and central nervous system.

Nuclear cardiac

International Nuclear Information System (INIS)

Slutsky, R.; Ashburn, W.L.

1982-01-01

The relationship between nuclear medicine and cardiology has continued to produce a surfeit of interesting, illuminating, and important reports involving the analysis of cardiac function, perfusion, and metabolism. To simplify the presentation, this review is broken down into three major subheadings: analysis of myocardial perfusion; imaging of the recent myocardial infarction; and the evaluation of myocardial function. There appears to be an increasingly important relationship between cardiology, particularly cardiac physiology, and nuclear imaging techniques

Alpha-cardiac myosin heavy chain (MYH6) mutations affecting myofibril formation are associated with congenital heart defects.

Science.gov (United States)

Granados-Riveron, Javier T; Ghosh, Tushar K; Pope, Mark; Bu'Lock, Frances; Thornborough, Christopher; Eason, Jacqueline; Kirk, Edwin P; Fatkin, Diane; Feneley, Michael P; Harvey, Richard P; Armour, John A L; David Brook, J

2010-10-15

Congenital heart defects (CHD) are collectively the most common form of congenital malformation. Studies of human cases and animal models have revealed that mutations in several genes are responsible for both familial and sporadic forms of CHD. We have previously shown that a mutation in MYH6 can cause an autosomal dominant form of atrial septal defect (ASD), whereas others have identified mutations of the same gene in patients with hypertrophic and dilated cardiomyopathy. In the present study, we report a mutation analysis of MYH6 in patients with a wide spectrum of sporadic CHD. The mutation analysis of MYH6 was performed in DNA samples from 470 cases of isolated CHD using denaturing high-performance liquid chromatography and sequence analysis to detect point mutations and small deletions or insertions, and multiplex amplifiable probe hybridization to detect partial or complete copy number variations. One non-sense mutation, one splicing site mutation and seven non-synonymous coding mutations were identified. Transfection of plasmids encoding mutant and non-mutant green fluorescent protein-MYH6 fusion proteins in mouse myoblasts revealed that the mutations A230P and A1366D significantly disrupt myofibril formation, whereas the H252Q mutation significantly enhances myofibril assembly in comparison with the non-mutant protein. Our data indicate that functional variants of MYH6 are associated with cardiac malformations in addition to ASD and provide a novel potential mechanism. Such phenotypic heterogeneity has been observed in other genes mutated in CHD.

Discovery and progress of direct cardiac reprogramming.

Science.gov (United States)

Kojima, Hidenori; Ieda, Masaki

2017-06-01

Cardiac disease remains a major cause of death worldwide. Direct cardiac reprogramming has emerged as a promising approach for cardiac regenerative therapy. After the discovery of MyoD, a master regulator for skeletal muscle, other single cardiac reprogramming factors (master regulators) have been sought. Discovery of cardiac reprogramming factors was inspired by the finding that multiple, but not single, transcription factors were needed to generate induced pluripotent stem cells (iPSCs) from fibroblasts. We first reported a combination of cardiac-specific transcription factors, Gata4, Mef2c, and Tbx5 (GMT), that could convert mouse fibroblasts into cardiomyocyte-like cells, which were designated as induced cardiomyocyte-like cells (iCMs). Following our first report of cardiac reprogramming, many researchers, including ourselves, demonstrated an improvement in cardiac reprogramming efficiency, in vivo direct cardiac reprogramming for heart regeneration, and cardiac reprogramming in human cells. However, cardiac reprogramming in human cells and adult fibroblasts remains inefficient, and further efforts are needed. We believe that future research elucidating epigenetic barriers and molecular mechanisms of direct cardiac reprogramming will improve the reprogramming efficiency, and that this new technology has great potential for clinical applications.

Optimal Technique in Cardiac Anesthesia Recovery

OpenAIRE

Svircevic, V.

2014-01-01

The aim of this thesis is to evaluate fast-track cardiac anesthesia techniques and investigate their impact on postoperative mortality, morbidity and quality of life. The following topics will be discussed in the thesis. (1.) Is fast track cardiac anesthesia a safe technique for cardiac surgery? (2.) Does thoracic epidural anesthesia have an effect on mortality and morbidity after cardiac surgery? (3.) Does thoracic epidural anesthesia have an effect on quality of life after cardiac surgery? ...

An integrated bioimpedance—ECG gating technique for respiratory and cardiac motion compensation in cardiac PET

International Nuclear Information System (INIS)

Koivumäki, Tuomas; Nekolla, Stephan G; Fürst, Sebastian; Loher, Simone; Schwaiger, Markus; Vauhkonen, Marko; Hakulinen, Mikko A

2014-01-01

Respiratory motion may degrade image quality in cardiac PET imaging. Since cardiac PET studies often involve cardiac gating by ECG, a separate respiratory monitoring system is required increasing the logistic complexity of the examination, in case respiratory gating is also needed. Thus, we investigated the simultaneous acquisition of both respiratory and cardiac gating signals using II limb lead mimicking electrode configuration during cardiac PET scans of 11 patients. In addition to conventional static and ECG-gated images, bioimpedance technique was utilized to generate respiratory- and dual-gated images. The ability of the bioimpedance technique to monitor intrathoracic respiratory motion was assessed estimating cardiac displacement between end-inspiration and -expiration. The relevance of dual gating was evaluated in left ventricular volume and myocardial wall thickness measurements. An average 7.6  ±  3.3 mm respiratory motion was observed in the study population. Dual gating showed a small but significant increase (4 ml, p = 0.042) in left ventricular myocardial volume compared to plain cardiac gating. In addition, a thinner myocardial wall was observed in dual-gated images (9.3  ±  1.3 mm) compared to cardiac-gated images (11.3  ±  1.3 mm, p = 0.003). This study shows the feasibility of bioimpedance measurements for dual gating in a clinical setting. The method enables simultaneous acquisition of respiratory and cardiac gating signals using a single device with standard ECG electrodes. (paper)

Glutaredoxin-2 controls cardiac mitochondrial dynamics and energetics in mice, and protects against human cardiac pathologies

Directory of Open Access Journals (Sweden)

Georges N. Kanaan

2018-04-01

Full Text Available Glutaredoxin 2 (GRX2, a mitochondrial glutathione-dependent oxidoreductase, is central to glutathione homeostasis and mitochondrial redox, which is crucial in highly metabolic tissues like the heart. Previous research showed that absence of Grx2, leads to impaired mitochondrial complex I function, hypertension and cardiac hypertrophy in mice but the impact on mitochondrial structure and function in intact cardiomyocytes and in humans has not been explored. We hypothesized that Grx2 controls cardiac mitochondrial dynamics and function in cellular and mouse models, and that low expression is associated with human cardiac dysfunction. Here we show that Grx2 absence impairs mitochondrial fusion, ultrastructure and energetics in primary cardiomyocytes and cardiac tissue. Moreover, provision of the glutathione precursor, N-acetylcysteine (NAC to Grx2-/- mice did not restore glutathione redox or prevent impairments. Using genetic and histopathological data from the human Genotype-Tissue Expression consortium we demonstrate that low GRX2 is associated with fibrosis, hypertrophy, and infarct in the left ventricle. Altogether, GRX2 is important in the control of cardiac mitochondrial structure and function, and protects against human cardiac pathologies. Keywords: Human heart, Mitochondria, Oxidative stress, Redox, Cardiac metabolism, Cardiac hypertrophy

Duchenne Muscular Dystrophy Gene Expression in Normal and Diseased Human Muscle

Science.gov (United States)

Oronzi Scott, M.; Sylvester, J. E.; Heiman-Patterson, T.; Shi, Y.-J.; Fieles, W.; Stedman, H.; Burghes, A.; Ray, P.; Worton, R.; Fischbeck, K. H.

1988-03-01

A probe for the 5' end of the Duchenne muscular dystrophy (DMD) gene was used to study expression of the gene in normal human muscle, myogenic cell cultures, and muscle from patients with DMD. Expression was found in RNA from normal fetal muscle, adult cardiac and skeletal muscle, and cultured muscle after myoblast fusion. In DMD muscle, expression of this portion of the gene was also revealed by in situ RNA hybridization, particularly in regenerating muscle fibers.

Cardiac expression of microsomal triglyceride transfer protein is increased in obesity and serves to attenuate cardiac triglyceride accumulation.

Directory of Open Access Journals (Sweden)

Emil D Bartels

Full Text Available Obesity causes lipid accumulation in the heart and may lead to lipotoxic heart disease. Traditionally, the size of the cardiac triglyceride pool is thought to reflect the balance between uptake and beta-oxidation of fatty acids. However, triglycerides can also be exported from cardiomyocytes via secretion of apolipoproteinB-containing (apoB lipoproteins. Lipoprotein formation depends on expression of microsomal triglyceride transfer protein (MTP; the mouse expresses two isoforms of MTP, A and B. Since many aspects of the link between obesity-induced cardiac disease and cardiac lipid metabolism remain unknown, we investigated how cardiac lipoprotein synthesis affects cardiac expression of triglyceride metabolism-controlling genes, insulin sensitivity, and function in obese mice. Heart-specific ablation of MTP-A in mice using Cre-loxP technology impaired upregulation of MTP expression in response to increased fatty acid availability during fasting and fat feeding. This resulted in cardiac triglyceride accumulation but unaffected cardiac insulin-stimulated glucose uptake. Long-term fat-feeding of male C57Bl/6 mice increased cardiac triglycerides, induced cardiac expression of triglyceride metabolism-controlling genes and attenuated heart function. Abolishing cardiac triglyceride accumulation in fat-fed mice by overexpression of an apoB transgene in the heart prevented the induction of triglyceride metabolism-controlling genes and improved heart function. The results suggest that in obesity, the physiological increase of cardiac MTP expression serves to attenuate cardiac triglyceride accumulation albeit without major effects on cardiac insulin sensitivity. Nevertheless, the data suggest that genetically increased lipoprotein secretion prevents development of obesity-induced lipotoxic heart disease.

Cardiac-specific overexpression of aldehyde dehydrogenase 2 exacerbates cardiac remodeling in response to pressure overload

Directory of Open Access Journals (Sweden)

Sujith Dassanayaka

2018-07-01

Full Text Available Pathological cardiac remodeling during heart failure is associated with higher levels of lipid peroxidation products and lower abundance of several aldehyde detoxification enzymes, including aldehyde dehydrogenase 2 (ALDH2. An emerging idea that could explain these findings concerns the role of electrophilic species in redox signaling, which may be important for adaptive responses to stress or injury. The purpose of this study was to determine whether genetically increasing ALDH2 activity affects pressure overload-induced cardiac dysfunction. Mice subjected to transverse aortic constriction (TAC for 12 weeks developed myocardial hypertrophy and cardiac dysfunction, which were associated with diminished ALDH2 expression and activity. Cardiac-specific expression of the human ALDH2 gene in mice augmented myocardial ALDH2 activity but did not improve cardiac function in response to pressure overload. After 12 weeks of TAC, ALDH2 transgenic mice had larger hearts than their wild-type littermates and lower capillary density. These findings show that overexpression of ALDH2 augments the hypertrophic response to pressure overload and imply that downregulation of ALDH2 may be an adaptive response to certain forms of cardiac pathology. Keywords: Heart failure, Hypertrophy, Oxidative stress, Aldehydes, Cardiac remodeling, Hormesis

Biosynthesis of cardiac natriuretic peptides

DEFF Research Database (Denmark)

Goetze, Jens Peter

2010-01-01

Cardiac-derived peptide hormones were identified more than 25 years ago. An astonishing amount of clinical studies have established cardiac natriuretic peptides and their molecular precursors as useful markers of heart disease. In contrast to the clinical applications, the biogenesis of cardiac...... peptides has only been elucidated during the last decade. The cellular synthesis including amino acid modifications and proteolytic cleavages has proven considerably more complex than initially perceived. Consequently, the elimination phase of the peptide products in circulation is not yet well....... An inefficient post-translational prohormone maturation will also affect the biology of the cardiac natriuretic peptide system. This review aims at summarizing the myocardial synthesis of natriuretic peptides focusing on B-type natriuretic peptide, where new data has disclosed cardiac myocytes as highly...

Bone Morphogenetic Protein 9 Reduces Cardiac Fibrosis and Improves Cardiac Function in Heart Failure.

Science.gov (United States)

Morine, Kevin J; Qiao, Xiaoying; York, Sam; Natov, Peter S; Paruchuri, Vikram; Zhang, Yali; Aronovitz, Mark J; Karas, Richard H; Kapur, Navin K

2018-02-27

Background -Heart failure is a growing cause of morbidity and mortality worldwide. Transforming growth factor beta (TGF-β1) promotes cardiac fibrosis, but also activates counter-regulatory pathways that serve to regulate TGF-β1 activity in heart failure. Bone morphogenetic protein 9 (BMP9) is a member of the TGFβ family of cytokines and signals via the downstream effector protein Smad1. Endoglin is a TGFβ co-receptor that promotes TGF-β1 signaling via Smad3 and binds BMP9 with high affinity. We hypothesized that BMP9 limits cardiac fibrosis by activating Smad1 and attenuating Smad3 and further that neutralizing endoglin activity promotes BMP9 activity. Methods -We examined BMP9 expression and signaling in human cardiac fibroblasts and human subjects with heart failure. We utilized the thoracic aortic constriction (TAC) induced model of heart failure to evaluate the functional effect of BMP9 signaling on cardiac remodeling. Results -BMP9 expression is increased in the circulation and left ventricle (LV) of human subjects with heart failure and is expressed by cardiac fibroblasts. Next, we observed that BMP9 attenuates Type I collagen synthesis in human cardiac fibroblasts using recombinant human BMP9 and an siRNA approach. In BMP9 -/- mice subjected to TAC, loss of BMP9 activity promotes cardiac fibrosis, impairs LV function, and increases LV levels of phosphorylated Smad3 (pSmad3), not pSmad1. In contrast, treatment of wild-type mice subjected to TAC with recombinant BMP9 limits progression of cardiac fibrosis, improves LV function, enhances myocardial capillary density, and increases LV levels of pSmad1, not pSmad3 compared to vehicle treated controls. Since endoglin binds BMP9 with high affinity, we explored the effect of reduced endoglin activity on BMP9 activity. Neutralizing endoglin activity in human cardiac fibroblasts or in wild-type mice subjected to TAC induced heart failure limits collagen production, increases BMP9 protein levels, and increases

Evaluation of respiratory and cardiac motion correction schemes in dual gated PET/CT cardiac imaging

Energy Technology Data Exchange (ETDEWEB)

Lamare, F., E-mail: frederic.lamare@chu-bordeaux.fr; Fernandez, P. [Univ. Bordeaux, INCIA, UMR 5287, F-33400 Talence (France); CNRS, INCIA, UMR 5287, F-33400 Talence (France); Service de Médecine Nucléaire, Hôpital Pellegrin, CHU de Bordeaux, 33076 Bordeaux (France); Le Maitre, A.; Visvikis, D. [INSERM, UMR1101, LaTIM, Université de Bretagne Occidentale, 29609 Brest (France); Dawood, M.; Schäfers, K. P. [European Institute for Molecular Imaging, University of Münster, Mendelstr. 11, 48149 Münster (Germany); Rimoldi, O. E. [Vita-Salute University and Scientific Institute San Raffaele, Milan, Italy and CNR Istituto di Bioimmagini e Fisiologia Molecolare, Milan (Italy)

2014-07-15

Purpose: Cardiac imaging suffers from both respiratory and cardiac motion. One of the proposed solutions involves double gated acquisitions. Although such an approach may lead to both respiratory and cardiac motion compensation there are issues associated with (a) the combination of data from cardiac and respiratory motion bins, and (b) poor statistical quality images as a result of using only part of the acquired data. The main objective of this work was to evaluate different schemes of combining binned data in order to identify the best strategy to reconstruct motion free cardiac images from dual gated positron emission tomography (PET) acquisitions. Methods: A digital phantom study as well as seven human studies were used in this evaluation. PET data were acquired in list mode (LM). A real-time position management system and an electrocardiogram device were used to provide the respiratory and cardiac motion triggers registered within the LM file. Acquired data were subsequently binned considering four and six cardiac gates, or the diastole only in combination with eight respiratory amplitude gates. PET images were corrected for attenuation, but no randoms nor scatter corrections were included. Reconstructed images from each of the bins considered above were subsequently used in combination with an affine or an elastic registration algorithm to derive transformation parameters allowing the combination of all acquired data in a particular position in the cardiac and respiratory cycles. Images were assessed in terms of signal-to-noise ratio (SNR), contrast, image profile, coefficient-of-variation (COV), and relative difference of the recovered activity concentration. Results: Regardless of the considered motion compensation strategy, the nonrigid motion model performed better than the affine model, leading to higher SNR and contrast combined with a lower COV. Nevertheless, when compensating for respiration only, no statistically significant differences were

Effects of local cardiac denervation on cardiac innervation and ventricular arrhythmia after chronic myocardial infarction.

Directory of Open Access Journals (Sweden)

Xudong Liu

Full Text Available Modulation of the autonomic nervous system (ANS has already been demonstrated to display antiarrhythmic effects in patients and animals with MI. In this study, we investigated whether local cardiac denervation has any beneficial effects on ventricular electrical stability and cardiac function in the chronic phase of MI.Twenty-one anesthetized dogs were randomly assigned into the sham-operated, MI and MI-ablation groups, respectively. Four weeks after local cardiac denervation, LSG stimulation was used to induce VPCs and VAs. The ventricular fibrillation threshold (VFT and the incidence of inducible VPCs were measured with electrophysiological protocol. Cardiac innervation was determined with immunohistochemical staining of growth associated protein-43 (GAP43 and tyrosine hydroxylase (TH. The global cardiac and regional ventricular function was evaluated with doppler echocardiography in this study.Four weeks after operation, the incidence of inducible VPC and VF in MI-ablation group were significantly reduced compared to the MI dogs (p<0.05. Moreover, local cardiac denervation significantly improved VFT in the infarcted border zone (p<0.05. The densities of GAP43 and TH-positive nerve fibers in the infarcted border zone in the MI-ablation group were lower than those in the MI group (p<0.05. However, the local cardiac denervation did not significantly improve cardiac function in the chronic phase of MI, determined by the left ventricle diameter (LV, left atrial diameter (LA, ejection fraction (EF.Summarily, in the chronic phase of MI, local cardiac denervation reduces the ventricular electrical instability, and attenuates spatial heterogeneity of sympathetic nerve reconstruction. Our study suggests that this methodology might decrease malignant ventricular arrhythmia in chronic MI, and has a great potential for clinical application.

Mitochondria-Targeted Antioxidant Prevents Cardiac Dysfunction Induced by Tafazzin Gene Knockdown in Cardiac Myocytes

Directory of Open Access Journals (Sweden)

Quan He

2014-01-01

Full Text Available Tafazzin, a mitochondrial acyltransferase, plays an important role in cardiolipin side chain remodeling. Previous studies have shown that dysfunction of tafazzin reduces cardiolipin content, impairs mitochondrial function, and causes dilated cardiomyopathy in Barth syndrome. Reactive oxygen species (ROS have been implicated in the development of cardiomyopathy and are also the obligated byproducts of mitochondria. We hypothesized that tafazzin knockdown increases ROS production from mitochondria, and a mitochondria-targeted antioxidant prevents tafazzin knockdown induced mitochondrial and cardiac dysfunction. We employed cardiac myocytes transduced with an adenovirus containing tafazzin shRNA as a model to investigate the effects of the mitochondrial antioxidant, mito-Tempo. Knocking down tafazzin decreased steady state levels of cardiolipin and increased mitochondrial ROS. Treatment of cardiac myocytes with mito-Tempo normalized tafazzin knockdown enhanced mitochondrial ROS production and cellular ATP decline. Mito-Tempo also significantly abrogated tafazzin knockdown induced cardiac hypertrophy, contractile dysfunction, and cell death. We conclude that mitochondria-targeted antioxidant prevents cardiac dysfunction induced by tafazzin gene knockdown in cardiac myocytes and suggest mito-Tempo as a potential therapeutic for Barth syndrome and other dilated cardiomyopathies resulting from mitochondrial oxidative stress.

Boosters and barriers for direct cardiac reprogramming.

Science.gov (United States)

Talkhabi, Mahmood; Zonooz, Elmira Rezaei; Baharvand, Hossein

2017-06-01

Heart disease is currently the most significant cause of morbidity and mortality worldwide, which accounts for approximately 33% of all deaths. Recently, a promising and alchemy-like strategy has been developed called direct cardiac reprogramming, which directly converts somatic cells such as fibroblasts to cardiac lineage cells such as cardiomyocytes (CMs), termed induced CMs or iCMs. The first in vitro cardiac reprogramming study, mediated by cardiac transcription factors (TFs)-Gata4, Tbx5 and Mef2C-, was not enough efficient to produce an adequate number of fully reprogrammed, functional iCMs. As a result, numerous combinations of cardiac TFs exist for direct cardiac reprogramming of mouse and human fibroblasts. However, the efficiency of direct cardiac reprogramming remains low. Recently, a number of cellular and molecular mechanisms have been identified to increase the efficiency of direct cardiac reprogramming and the quality of iCMs. For example, microgrooved substrate, cardiogenic growth factors [VEGF, FGF, BMP4 and Activin A], and an appropriate stoichiometry of TFs boost the direct cardiac reprogramming. On the other hand, serum, TGFβ signaling, activators of epithelial to mesenchymal transition, and some epigenetic factors (Bmi1 and Ezh2) are barriers for direct cardiac reprogramming. Manipulating these mechanisms by the application of boosters and removing barriers can increase the efficiency of direct cardiac reprogramming and possibly make iCMs reliable for cell-based therapy or other potential applications. In this review, we summarize the latest trends in cardiac TF- or miRNA-based direct cardiac reprogramming and comprehensively discuses all molecular and cellular boosters and barriers affecting direct cardiac reprogramming. Copyright © 2017 Elsevier Inc. All rights reserved.

Imaging in cardiac mass lesions

International Nuclear Information System (INIS)

Mundinger, A.; Gruber, H.P.; Dinkel, E.; Geibel, A.; Beck, A.; Wimmer, B.; Schlosser, V.

1992-01-01

In 26 patients with cardiac mass lesions confirmed by surgery, diagnostic imaging was performed preoperatively by means of two-dimensional echocardiography (26 patients), angiography (12 patients), correlative computed tomography (CT, 8 patients), and magnetic resonance imaging (MRI, 3 patients). Two-dimensional echocardiography correctly identified the cardiac masses in all patients. Angiography missed two of 12 cardiac masses; CT missed one of eight. MRI identified three of three cardiac masses. Although the sensitivity of two-dimensional echocardiography was high (100%), all methods lacked specificity. None of the methods allowed differentiation between myxoma (n=13) and thrombus (n=7). Malignancy of the lesions was successfully predicted by noninvasive imaging methods in all six patients. However, CT and MRI provided additional information concerning cardiac mural infiltration, pericardial involvement, and extracardiac tumor extension, and should be integrated within a preoperative imaging strategy. Thus two-dimensional echocardiography is the method of choice for primary assessment of patients with suspected cardiac masses. Further preoperative imaging by CT or MRI can be limited to patients with malignancies suspected on the grounds of pericardial effusion or other clinical results. (author)

4,4'-Dichlorodiphenyltrichloroethane (DDT) and 4,4'-dichlorodiphenyldichloroethylene (DDE) inhibit myogenesis in C2C12 myoblasts.

Science.gov (United States)

Kim, Jonggun; Park, Min Young; Kim, Yoo; Yoon, Kyong Sup; Clark, John Marshall; Park, Yeonhwa; Whang, Kwang-Youn

2017-12-01

Most countries have banned the use of 4,4'-dichlorodiphenyltrichloroethane (DDT). However, owing to its extremely high lipophilic characteristics, DDT and its metabolite 4,4'-dichlorodiphenyldichloroethylene (DDE) are ubiquitous in the environment and in many types of food. The positive correlation between exposure to insecticides, including DDT and DDE, and weight gain, resulting in impaired energy metabolism in offspring following perinatal DDT and DDE exposure, was previously reported. Therefore the influence of DDT and DDE on myogenesis using C2C12 myoblasts was investigated in this study. DDT and DDE decreased myotube formation dose- and time-dependently. Among myogenic regulatory factors, DDT and DDE mainly decreased MyoD1 and Myf5 expression. DDT and DDE treatment also altered Myostatin expression, phosphorylation of protein kinase B, p70 ribosomal protein S6 kinase, forkhead box O protein 3 and mammalian target of rapamycin, resulting in attenuation of myotube formation. These results may have significant implications for understanding the effects of developmental exposure of DDT and DDE on myogenesis and development of obesity and type 2 diabetes later in life. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Reduced Right Ventricular Function Predicts Long-Term Cardiac Re-Hospitalization after Cardiac Surgery.

Directory of Open Access Journals (Sweden)

Leela K Lella

Full Text Available The significance of right ventricular ejection fraction (RVEF, independent of left ventricular ejection fraction (LVEF, following isolated coronary artery bypass grafting (CABG and valve procedures remains unknown. The aim of this study is to examine the significance of abnormal RVEF by cardiac magnetic resonance (CMR, independent of LVEF in predicting outcomes of patients undergoing isolated CABG and valve surgery.From 2007 to 2009, 109 consecutive patients (mean age, 66 years; 38% female were referred for pre-operative CMR. Abnormal RVEF and LVEF were considered 30 days outcomes included, cardiac re-hospitalization, worsening congestive heart failure and mortality. Mean clinical follow up was 14 months.Forty-eight patients had reduced RVEF (mean 25% and 61 patients had normal RVEF (mean 50% (p<0.001. Fifty-four patients had reduced LVEF (mean 30% and 55 patients had normal LVEF (mean 59% (p<0.001. Patients with reduced RVEF had a higher incidence of long-term cardiac re-hospitalization vs. patients with normal RVEF (31% vs.13%, p<0.05. Abnormal RVEF was a predictor for long-term cardiac re-hospitalization (HR 3.01 [CI 1.5-7.9], p<0.03. Reduced LVEF did not influence long-term cardiac re-hospitalization.Abnormal RVEF is a stronger predictor for long-term cardiac re-hospitalization than abnormal LVEF in patients undergoing isolated CABG and valve procedures.

The Influence of Cardiac Risk Factor Burden on Cardiac Stress Test Outcomes.

Science.gov (United States)

Schrock, Jon W; Li, Morgan; Orazulike, Chidubem; Emerman, Charles L

2011-06-01

Chest pain is the most common admission diagnosis for observation unit patients. These patients often undergo cardiac stress testing to further risk stratify for coronary artery disease (CAD). The decision of whom to stress is currently based on clinical judgment. We sought to determine the influence of cardiac risk factor burden on cardiac stress test outcome for patients tested from an observation unit, inpatient or outpatient setting. We performed a retrospective observational cohort study for all patients undergoing stress testing in our institution from June 2006 through July 2007. Cardiac risk factors were collected at the time of stress testing. Risk factors were evaluated in a summative fashion using multivariate regression adjusting for age and known coronary artery disease. The model was tested for goodness of fit and collinearity and the c statistic was calculated using the receiver operating curve. A total of 4026 subjects were included for analysis of which 22% had known CAD. The rates of positive outcome were 89 (12.0%), 95 (12.6%), and 343 (16.9%) for the OU, outpatients, and hospitalized patients respectively. While the odds of a positive test outcome increased for additional cardiac risk factors, ROC curve analysis indicates that simply adding the number of risk factors does not add significant diagnostic value. Hospitalized patients were more likely to have a positive stress test, OR 1.41 (1.10 - 1.81). Our study does not support basing the decision to perform a stress test on the number of cardiac risk factors.

Cardiac Arrest: MedlinePlus Health Topic

Science.gov (United States)

... Handouts Cardiac arrest (Medical Encyclopedia) Also in Spanish Topic Image MedlinePlus Email Updates Get Cardiac Arrest updates ... this? GO MEDICAL ENCYCLOPEDIA Cardiac arrest Related Health Topics Arrhythmia CPR Pacemakers and Implantable Defibrillators National Institutes ...

Trends in Cardiac Pacemaker Batteries

Directory of Open Access Journals (Sweden)

Venkateswara Sarma Mallela

2004-10-01

Full Text Available Batteries used in Implantable cardiac pacemakers-present unique challenges to their developers and manufacturers in terms of high levels of safety and reliability. In addition, the batteries must have longevity to avoid frequent replacements. Technological advances in leads/electrodes have reduced energy requirements by two orders of magnitude. Micro-electronics advances sharply reduce internal current drain concurrently decreasing size and increasing functionality, reliability, and longevity. It is reported that about 600,000 pacemakers are implanted each year worldwide and the total number of people with various types of implanted pacemaker has already crossed 3 million. A cardiac pacemaker uses half of its battery power for cardiac stimulation and the other half for housekeeping tasks such as monitoring and data logging. The first implanted cardiac pacemaker used nickel-cadmium rechargeable battery, later on zinc-mercury battery was developed and used which lasted for over 2 years. Lithium iodine battery invented and used by Wilson Greatbatch and his team in 1972 made the real impact to implantable cardiac pacemakers. This battery lasts for about 10 years and even today is the power source for many manufacturers of cardiac pacemakers. This paper briefly reviews various developments of battery technologies since the inception of cardiac pacemaker and presents the alternative to lithium iodine battery for the near future.

Cardiac radiology: centenary review.

Science.gov (United States)

de Roos, Albert; Higgins, Charles B

2014-11-01

During the past century, cardiac imaging technologies have revolutionized the diagnosis and treatment of acquired and congenital heart disease. Many important contributions to the field of cardiac imaging were initially reported in Radiology. The field developed from the early stages of cardiac imaging, including the use of coronary x-ray angiography and roentgen kymography, to nowadays the widely used echocardiographic, nuclear medicine, cardiac computed tomographic (CT), and magnetic resonance (MR) applications. It is surprising how many of these techniques were not recognized for their potential during their early inception. Some techniques were described in the literature but required many years to enter the clinical arena and presently continue to expand in terms of clinical application. The application of various CT and MR contrast agents for the diagnosis of myocardial ischemia is a case in point, as the utility of contrast agents continues to expand the noninvasive characterization of myocardium. The history of cardiac imaging has included a continuous process of advances in our understanding of the anatomy and physiology of the cardiovascular system, along with advances in imaging technology that continue to the present day.

The impact of obesity in the cardiac lipidome and its consequences in the cardiac damage observed in obese rats.

Science.gov (United States)

Marín-Royo, Gema; Martínez-Martínez, Ernesto; Gutiérrez, Beatriz; Jurado-López, Raquel; Gallardo, Isabel; Montero, Olimpio; Bartolomé, Mª Visitación; Román, José Alberto San; Salaices, Mercedes; Nieto, María Luisa; Cachofeiro, Victoria

To explore the impact of obesity on the cardiac lipid profile in rats with diet-induced obesity, as well as to evaluate whether or not the specific changes in lipid species are associated with cardiac fibrosis. Male Wistar rats were fed either a high-fat diet (HFD, 35% fat) or standard diet (3.5% fat) for 6 weeks. Cardiac lipids were analyzed using by liquid chromatography-tandem mass spectrometry. HFD rats showed cardiac fibrosis and enhanced levels of cardiac superoxide anion (O 2 ), HOMA index, adiposity, and plasma leptin, as well as a reduction in those of cardiac glucose transporter (GLUT 4), compared with control animals. Cardiac lipid profile analysis showed a significant increase in triglycerides, especially those enriched with palmitic, stearic, and arachidonic acid. An increase in levels of diacylglycerol (DAG) was also observed. No changes in cardiac levels of diacyl phosphatidylcholine, or even a reduction in total levels of diacyl phosphatidylethanolamine, diacyl phosphatidylinositol, and sphingomyelins (SM) was observed in HFD, as compared with control animals. After adjustment for other variables (oxidative stress, HOMA, cardiac hypertrophy), total levels of DAG were independent predictors of cardiac fibrosis while the levels of total SM were independent predictors of the cardiac levels of GLUT 4. These data suggest that obesity has a significant impact on cardiac lipid composition, although it does not modulate the different species in a similar manner. Nonetheless, these changes are likely to participate in the cardiac damage in the context of obesity, since total DAG levels can facilitate the development of cardiac fibrosis, and SM levels predict GLUT4 levels. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

[Cardiac cachexia].

Science.gov (United States)

Miján, Alberto; Martín, Elvira; de Mateo, Beatriz

2006-05-01

Chronic heart failure (CHF), especially affecting the right heart, frequently leads to malnutrition. If the latter is severe and is combined to other factors, it may lead to cardiac cachexia. This one is associated to increased mortality and lower survival of patients suffering from it. The causes of cardiac cachexia are diverse, generally associated to maintenance of a negative energy balance, with increasing evidence of its multifactorial origin. Neurohumoral, inflammatory, immunological, and metabolic factors, among others, are superimposed in the patient with CHF, leading to involvement and deterioration of several organs and systems, since this condition affects both lean (or active cellular) mass and adipose and bone tissue osteoporosis. Among all, the most pronounced deterioration may be seen at skeletal muscle tissue, at both structural and functional levels, the heart not being spared. As for treatment, it should be based on available scientific evidence. Assessment of nutritional status of any patient with CHF is a must, with the requirement of nutritional intervention in case of malnutrition. In this situation, especially if accompanied by cardiac cachexia, it is required to modify energy intake and oral diet quality, and to consider the indication of specific complementary or alternative artificial nutrition. Besides, the causal relationship of the beneficial role of moderate physical exertion is increasing, as well as modulation of metabolic and inflammatory impairments observed in cardiac cachexia with several drugs, leading to a favorable functional and structural response in CHF patients.

Cardiac Catheterization (For Kids)

Science.gov (United States)

... First Aid & Safety Doctors & Hospitals Videos Recipes for Kids Kids site Sitio para niños How the Body Works ... Educators Search English Español Cardiac Catheterization KidsHealth / For Kids / Cardiac Catheterization What's in this article? What Is ...

Imaging in blunt cardiac injury: Computed tomographic findings in cardiac contusion and associated injuries.

Science.gov (United States)

Hammer, Mark M; Raptis, Demetrios A; Cummings, Kristopher W; Mellnick, Vincent M; Bhalla, Sanjeev; Schuerer, Douglas J; Raptis, Constantine A

2016-05-01

Blunt cardiac injury (BCI) may manifest as cardiac contusion or, more rarely, as pericardial or myocardial rupture. Computed tomography (CT) is performed in the vast majority of blunt trauma patients, but the imaging features of cardiac contusion are not well described. To evaluate CT findings and associated injuries in patients with clinically diagnosed BCI. We identified 42 patients with blunt cardiac injury from our institution's electronic medical record. Clinical parameters, echocardiography results, and laboratory tests were recorded. Two blinded reviewers analyzed chest CTs performed in these patients for myocardial hypoenhancement and associated injuries. CT findings of severe thoracic trauma are commonly present in patients with severe BCI; 82% of patients with ECG, cardiac enzyme, and echocardiographic evidence of BCI had abnormalities of the heart or pericardium on CT; 73% had anterior rib fractures, and 64% had pulmonary contusions. Sternal fractures were only seen in 36% of such patients. However, myocardial hypoenhancement on CT is poorly sensitive for those patients with cardiac contusion: 0% of right ventricular contusions and 22% of left ventricular contusions seen on echocardiography were identified on CT. CT signs of severe thoracic trauma are frequently present in patients with severe BCI and should be regarded as indirect evidence of potential BCI. Direct CT findings of myocardial contusion, i.e. myocardial hypoenhancement, are poorly sensitive and should not be used as a screening tool. However, some left ventricular contusions can be seen on CT, and these patients could undergo echocardiography or cardiac MRI to evaluate for wall motion abnormalities. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cardiac changes in anorexia nervosa.

Science.gov (United States)

Spaulding-Barclay, Michael A; Stern, Jessica; Mehler, Philip S

2016-04-01

Introduction Anorexia nervosa is an eating disorder, which is associated with many different medical complications as a result of the weight loss and malnutrition that characterise this illness. It has the highest mortality rate of any psychiatric disorder. A large portion of deaths are attributable to the cardiac abnormalities that ensue as a result of the malnutrition associated with anorexia nervosa. In this review, the cardiac complications of anorexia nervosa will be discussed. A comprehensive literature review on cardiac changes in anorexia nervosa was carried out. There are structural, functional, and rhythm-type changes that occur in patients with anorexia nervosa. These become progressively significant as ongoing weight loss occurs. Cardiac changes are inherent to anorexia nervosa and they become more life-threatening and serious as the anorexia nervosa becomes increasingly severe. Weight restoration and attention to these cardiac changes are crucial for a successful treatment outcome.

Obesity-associated cardiac pathogenesis in broiler breeder hens: Pathological adaption of cardiac hypertrophy.

Science.gov (United States)

Chen, C Y; Lin, H Y; Chen, Y W; Ko, Y J; Liu, Y J; Chen, Y H; Walzem, R L; Chen, S E

2017-07-01

Broiler hens consuming feed to appetite (ad libitum; AL) show increased mortality. Feed restriction (R) typically improves reproductive performance and livability of hens. Rapidly growing broilers can exhibit increased mortality due to cardiac insufficiency but it is unknown whether the increased mortality of non-R broiler hens is also due to cardiac compromise. To assess cardiac growth and physiology in fully mature birds, 45-week-old hens were either continued on R rations or assigned to AL feeding for 7 or 21 days. AL hens exhibited increased bodyweight, adiposity, absolute and relative heart weight, ventricular hypertrophy, and cardiac protein/DNA ratio by d 21 (P hens (P Hens allowed AL feeding for 70 d exhibited a higher incidence of mortality (40% vs. 10%) in association with ascites, pericardial effusion, and ventricle dilation. A higher incidence of irregular ECG patterns and rhythmicity consistent with persistently elevated systolic blood pressure and ventricle fibrosis were observed in AL hens (P feeding in broiler hens results in maladaptive cardiac hypertrophy that progresses to overt pathogenesis in contractility and thereby increases mortality. Feed restriction provides clear physiological benefit to heart function of adult broiler hens. © 2017 Poultry Science Association Inc.

Characterization of Glutamatergic Neurons in the Rat Atrial Intrinsic Cardiac Ganglia that Project to the Cardiac Ventricular Wall

Science.gov (United States)

Wang, Ting; Miller, Kenneth E.

2016-01-01

The intrinsic cardiac nervous system modulates cardiac function by acting as an integration site for regulating autonomic efferent cardiac output. This intrinsic system is proposed to be composed of a short cardio-cardiac feedback control loop within the cardiac innervation hierarchy. For example, electrophysiological studies have postulated the presence of sensory neurons in intrinsic cardiac ganglia for regional cardiac control. There is still a knowledge gap, however, about the anatomical location and neurochemical phenotype of sensory neurons inside intrinsic cardiac ganglia. In the present study, rat intrinsic cardiac ganglia neurons were characterized neurochemically with immunohistochemistry using glutamatergic markers: vesicular glutamate transporters 1 and 2 (VGLUT1; VGLUT2), and glutaminase (GLS), the enzyme essential for glutamate production. Glutamatergic neurons (VGLUT1/VGLUT2/GLS) in the ICG that have axons to the ventricles were identified by retrograde tracing of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) injected in the ventricular wall. Co-labeling of VGLUT1, VGLUT2, and GLS with the vesicular acetylcholine transporter (VAChT) was used to evaluate the relationship between post-ganglionic autonomic neurons and glutamatergic neurons. Sequential labeling of VGLUT1 and VGLUT2 in adjacent tissue sections was used to evaluate the co-localization of VGLUT1 and VGLUT2 in ICG neurons. Our studies yielded the following results: (1) intrinsic cardiac ganglia contain glutamatergic neurons with GLS for glutamate production and VGLUT1 and 2 for transport of glutamate into synaptic vesicles; (2) atrial intrinsic cardiac ganglia contain neurons that project to ventricle walls and these neurons are glutamatergic; (3) many glutamatergic ICG neurons also were cholinergic, expressing VAChT. (4) VGLUT1 and VGLUT2 co-localization occurred in ICG neurons with variation of their protein expression level. Investigation of both glutamatergic and cholinergic ICG

Scoring of late gadolinium enhancement in cardiac magnetic resonance imaging can predict cardiac events in patients with hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Nojiri, Ayumi; Hongo, Kenichi; Kawai, Makoto; Komukai, Kimiaki; Sakuma, Toru; Taniguchi, Ikuo; Yoshimura, Michihiro

2011-01-01

Late gadolinium enhancement (LGE) of cardiac magnetic resonance imaging (MRI) represents myocardial fibrosis and may be related to the clinical outcome of various heart diseases. This study evaluated the relationship between LGE and cardiac events in hypertrophic cardiomyopathy (HCM) using a new scoring method. This study retrospectively followed 46 HCM patients without heart failure symptoms for 3.8±1.8 years. Gadolinium-enhanced cardiac MRI was performed in all patients. Cardiac events including newly developed heart failure or ventricular tachyarrhythmia were evaluated during the follow-up period. We evaluated the predictive factors to identify the patients with cardiac events. None of the risk factors reported to be related to poor outcome or the existence of LGE alone could predict cardiac events, which might be due to the small number of subjects investigated in this study. A new scoring method for LGE-positive areas (LGE score) was applied and higher LGE score can predict cardiac events in this study population. The proposed LGE score for cardiac MRI is considered to be a potentially valid method for assessing cardiac events in HCM patients. (author)

Safety in cardiac surgery

NARCIS (Netherlands)

Siregar, S.

2013-01-01

The monitoring of safety in cardiac surgery is a complex process, which involves many clinical, practical, methodological and statistical issues. The objective of this thesis was to measure and to compare safety in cardiac surgery in The Netherlands using the Netherlands Association for

Fetal Primary Cardiac Tumors During Perinatal Period

Directory of Open Access Journals (Sweden)

Shi-Min Yuan

2017-06-01

Full Text Available Fetal primary cardiac tumors are rare, but they may cause complications, which are sometimes life threatening, including arrhythmias, hydrops fetalis, ventricular outflow/inflow obstruction, cardiac failure, and even sudden death. Among fetal primary cardiac tumors, rhabdomyomas are most common, followed by teratomas, fibromas, hemangiomas, and myxomas. Everolimus, a mammalian target of rapamycin inhibitor, has been reported to be an effective drug to cause tumor remission in three neonates with multiple cardiac rhabdomyomas. Neonatal cardiac surgery for the resection of primary cardiac tumors found by fetal echocardiography has been reported sporadically. However, open fetal surgery for pericardial teratoma resection, which was performed successfully via a fetal median sternotomy in one case report, could be a promising intervention to rescue these patients with large pericardial effusions. These recent achievements undoubtedly encourage further development in early management of fetal cardiac tumors. Owing to the rarity of fetal primary cardiac tumors, relevant information in terms of prenatal diagnosis, treatment, and prognosis remains to be clarified.

Bupivacaine can enhance lysosomal activity in mouse muscle myoblasts%布比卡因增强小鼠成肌细胞溶酶体的活性

Institute of Scientific and Technical Information of China (English)

熊静薇; 毛雨; 李荣荣; 丁正年

2015-01-01

Objective To investigate the effects of bupivacaine on lysosomal abundance and activity in mouse muscle myoblasts.Methods Mouse myoblasts C2C12 was randomly divided into control group (without any treatment) and bupivacaine group (treated with bupivacaine 600 μ mol/L for 6 h).After then,the changes of lysosomal pH was assessed by LysoSensor pH indicator.The content of lysosomes was detected by LysoTracker probe.The expression of lysosomal-associated membrane protein-1 (LAMP-1) and Cathepsin B was detected by Western blot analysis.The activity of lysosomal proteolytic enzymes Cathepsin B was determined by MagicRed assay kit.Results Bupivacaine did not affect lysosomal pH.However,compared with the controls,lysosomal abundance was significantly increased 15.15％ following bupivacaine treatment(P＜0.01).Moreover,protein expression levels of LAMP-1 and Cathepsin B were significantly upregulated 36.41％ and 35.29％ respetctively by bupivacaine (P＜0.01).Furthermore,the activity of Cathepsin B was significantly increased 23.74％ by bupivacaine(P＜0.01).Conclusions Bupivacaine increased lysosomal content and enhance lysosomal activity in mouse muscle myoblasts.%目的 探讨局部麻醉药布比卡因对小鼠成肌细胞溶酶体的影响. 方法 将体外培养的小鼠成肌细胞C2C12分为2组.对照组:不加任何药物;布比卡因组:以600μmol/L布比卡因刺激细胞6h.实验结束后,用LysoSensor探针评价溶酶体腔pH,用LysoTrackor探针检测溶酶体含量,用蛋白免疫印迹法检测溶酶体相关膜蛋白-1(LAMP-1)和溶酶体蛋白水解酶Cathepsin B的表达水平,并以MagicRed染色法测定Cathepsin B的活性.结果 布比卡因对溶酶体腔pH没有影响.但是,与对照组相比,布比卡因组溶酶体含量增加15.15％ (P＜0.01),LAMP-1与Cathepsin B表达量分别增加36.41％、35.29％ (P＜0.01),Cathepsin B活性增加23.74％(P＜0.01).结论 布比卡因能增加小鼠成肌细胞溶酶体含量,增强溶酶体活性.

Focused cardiac ultrasound is feasible in the general practice setting and alters diagnosis and management of cardiac disease

Directory of Open Access Journals (Sweden)

James Yates

2016-08-01

Full Text Available Background: Ultrasound-assisted examination of the cardiovascular system with focused cardiac ultrasound by the treating physician is non-invasive and changes diagnosis and management of patient’s with suspected cardiac disease. This has not been reported in a general practice setting. Aim: To determine whether focused cardiac ultrasound performed on patients aged over 50 years changes the diagnosis and management of cardiac disease by a general practitioner. Design and setting: A prospective observational study of 80 patients aged over 50 years and who had not received echocardiography or chest CT within 12 months presenting to a general practice. Method: Clinical assessment and management of significant cardiac disorders in patients presenting to general practitioners were recorded before and after focused cardiac ultrasound. Echocardiography was performed by a medical student with sufficient training, which was verified by an expert. Differences in diagnosis and management between conventional and ultrasound-assisted assessment were recorded. Results and conclusion: Echocardiography and interpretation were acceptable in all patients. Significant cardiac disease was detected in 16 (20% patients, including aortic stenosis in 9 (11% and cardiac failure in 7 (9%, which were missed by clinical examination in 10 (62.5% of these patients. Changes in management occurred in 12 patients (15% overall and 75% of those found to have significant cardiac disease including referral for diagnostic echocardiography in 8 (10%, commencement of heart failure treatment in 3 (4% and referral to a cardiologist in 1 patient (1%. Routine focused cardiac ultrasound is feasible and frequently alters the diagnosis and management of cardiac disease in patients aged over 50 years presenting to a general practice.

Cardiac integrins the ties that bind.

Science.gov (United States)

Simpson, D G; Reaves, T A; Shih, D T; Burgess, W; Borg, T K; Terracio, L

1998-01-01

An elaborate series of morphogenetic events must be precisely coordinated during development to promote the formation of the elaborate three-dimensional structure of the normal heart. In this study we focus on discussing how interconnections between the cardiac myocyte and its surrounding environment regulate cardiac form and function. In vitro experiments from our laboratories provide direct evidence that cardiac cell shape is regulated by a dynamic interaction between constituents of the extracellular matrix (ECM) and by specific members of the integrin family of matrix receptors. Our data indicates that phenotypic information is stored in the tertiary structure and chemical identity of the ECM. This information appears to be actively communicated and transduced by the α1β1 integrin molecule into an intracellular signal that regulates cardiac cell shape and myofibrillar organization. In this study we have assessed the phenotypic consequences of suppressing the expression and accumulation of the α1 integrin molecule in aligned cultures of cardiac myocytes. In related experiments we have examined how the overexpression of α2 and α5 integrin, integrins normally not present or present at very low copy number on the cell surface of neonatal cardiac myocytes, affect cardiac protein metabolism. We also consider how biochemical signals and the mechanical signals mediated by the integrins may converge on common intracellular signaling pathways in the heart. Experiments with the whole embryo culture system indicate that angiotensin II, a peptide that carries information concerning cardiac load, plays a role in controling cardiac looping and the proliferation of myofibrils during development.

Cardiac fluid dynamics meets deformation imaging.

Science.gov (United States)

Dal Ferro, Matteo; Stolfo, Davide; De Paris, Valerio; Lesizza, Pierluigi; Korcova, Renata; Collia, Dario; Tonti, Giovanni; Sinagra, Gianfranco; Pedrizzetti, Gianni

2018-02-20

Cardiac function is about creating and sustaining blood in motion. This is achieved through a proper sequence of myocardial deformation whose final goal is that of creating flow. Deformation imaging provided valuable contributions to understanding cardiac mechanics; more recently, several studies evidenced the existence of an intimate relationship between cardiac function and intra-ventricular fluid dynamics. This paper summarizes the recent advances in cardiac flow evaluations, highlighting its relationship with heart wall mechanics assessed through the newest techniques of deformation imaging and finally providing an opinion of the most promising clinical perspectives of this emerging field. It will be shown how fluid dynamics can integrate volumetric and deformation assessments to provide a further level of knowledge of cardiac mechanics.

Dual energy cardiac CT.

Science.gov (United States)

Carrascosa, Patricia; Deviggiano, Alejandro; Rodriguez-Granillo, Gastón

2017-06-01

Conventional single energy CT suffers from technical limitations related to the polychromatic nature of X-rays. Dual energy cardiac CT (DECT) shows promise to attenuate and even overcome some of these limitations, and might broaden the scope of patients eligible for cardiac CT towards the inclusion of higher risk patients. This might be achieved as a result of both safety (contrast reduction) and physiopathological (myocardial perfusion and characterization) issues. In this article, we will review the main clinical cardiac applications of DECT, that can be summarized in two core aspects: coronary artery evaluation, and myocardial evaluation.

The cardiac sonography workforce in New Zealand

Science.gov (United States)

White, Steve; Poppe, Katrina; Whalley, Gillian

2015-01-01

Abstract Introduction: The aim of this paper is to investigate the cardiac sonography workforce characteristics and registration requirements in New Zealand (NZ), with a comparison to similar workforces internationally. Methods: The Survey of Clinical Echocardiography in New Zealand 2 (SCANZ2) audit was performed in December 2010. All of NZ's public‐funded District Health Board (DHB) centers providing echocardiography services responded to questions relating to staff, equipment, procedure types and patient statistics. The Medical Radiation Technologists Board (MRTB), Clinical Physiologists Registration Board (CPRB) and Australian Sonographers Association Registry (ASAR) websites were reviewed in March 2012 for registered sonographers with a cardiac scope of practice. The cardiac sonography workforces in Australia, the UK, the USA and Canada were investigated for comparison. Results: There are 84 cardiac sonographers (60.3 full‐time equivalent) working in DHBs: 71% from a cardiac technical background; 40% have post‐graduate qualifications; a further 17% are undertaking post‐graduate qualifications; and 59 cardiac sonographers have registration with professional bodies in NZ and/or Australia. Cardiac sonographers in NZ do not undergo compulsory registration, but other sonographers in NZ have compulsory registration with the MRTB. Sonographers are predominantly not licensed internationally. Discussion: Disparity exists between registration of cardiac and non‐cardiac sonographers in NZ. Many cardiac sonographers have voluntary registration but few are registered with the MRTB. Reasons for this include professional alignment, educational qualifications and representation. International trends show increased pressure from governments and professional bodies to regulate sonographers. Conclusion: This study provides a snapshot of the cardiac sonography workforce in NZ for the first time. PMID:28191178

Optimal Technique in Cardiac Anesthesia Recovery

NARCIS (Netherlands)

Svircevic, V.

2014-01-01

The aim of this thesis is to evaluate fast-track cardiac anesthesia techniques and investigate their impact on postoperative mortality, morbidity and quality of life. The following topics will be discussed in the thesis. (1.) Is fast track cardiac anesthesia a safe technique for cardiac surgery?

Emergency room thoracotomy for acute traumatic cardiac tamponade caused by a blunt cardiac injury: A case report

Directory of Open Access Journals (Sweden)

Kenichiro Ishida

2017-01-01

Conclusion: A prompt diagnosis using FAST and treatment can be lifesaving in traumatic acute cardiac tamponade. A pericardiotomy via a thoracotomy is mandatory for lifesaving cardiac decompression in acute traumatic cardiac tamponade in cases of ineffective drainage due to clot formation within the pericardial space.

Motivational factors of adherence to cardiac rehabilitation.

Science.gov (United States)

Shahsavari, Hooman; Shahriari, Mohsen; Alimohammadi, Nasrollah

2012-05-01

Main suggested theories about patients' adherence to treatment regimens recognize the importance of motivation in positive changes in behaviors. Since cardiac diseases are chronic and common, cardiac rehabilitation as an effective prevention program is crucial in management of these diseases. There is always concern about the patients' adherence to cardiac rehabilitation. The aim of this study was to describe the motivational factors affecting the patients' participation and compliance to cardiac rehabilitation by recognizing and understanding the nature of patients' experiences. The participants were selected among the patients with cardiac diseases who were referred to cardiac rehabilitation in Isfahan Cardiovascular Research Center, Iran. The purposive sampling method was used and data saturation achieved after 8 semi-structured interviews. The three main concepts obtained from this study are "beliefs", "supporters" and "group cohesion". In cardiac rehabilitation programs, emphasis on motivational factors affects the patient's adherence. It is suggested that in cardiac rehabilitation programs more attention should be paid to patients' beliefs, the role of patients' supporters and the role of group-based rehabilitation.

Cardiac Limited Ultrasound Examination Techniques to Augment the Bedside Cardiac Physical Examination.

Science.gov (United States)

Kimura, Bruce J; Shaw, David J; Amundson, Stan A; Phan, James N; Blanchard, Daniel G; DeMaria, Anthony N

2015-09-01

The current practice of physical diagnosis is dependent on physician skills and biases, inductive reasoning, and time efficiency. Although the clinical utility of echocardiography is well known, few data exist on how to integrate 2-dimensional screening "quick-look" ultrasound applications into a novel, modernized cardiac physical examination. We discuss the evidence basis behind ultrasound "signs" pertinent to the cardiovascular system and elemental in synthesis of bedside diagnoses and propose the application of a brief cardiac limited ultrasound examination based on these signs. An ultrasound-augmented cardiac physical examination can be taught in traditional medical education and has the potential to improve bedside diagnosis and patient care. © 2015 by the American Institute of Ultrasound in Medicine.

Crisis management during anaesthesia: cardiac arrest.

Science.gov (United States)

Runciman, W B; Morris, R W; Watterson, L M; Williamson, J A; Paix, A D

2005-06-01

Cardiac arrest attributable to anaesthesia occurs at the rate of between 0.5 and 1 case per 10 000 cases, tends to have a different profile to that of cardiac arrest occurring elsewhere, and has an in-hospital mortality of 20%. However, as individual practitioners encounter cardiac arrest rarely, the rapidity with which the diagnosis is made and the consistency of appropriate management varies considerably. To examine the role of a previously described core algorithm "COVER ABCD-A SWIFT CHECK", supplemented by a sub-algorithm for cardiac arrest, in the management of cardiac arrest occurring in association with anaesthesia. The potential performance of this structured approach for each the relevant incidents among the first 4000 reported to the Australian Incident Monitoring Study (AIMS) was compared with the actual management as reported by the anaesthetists involved. There were 129 reports of cardiac arrest associated with anaesthesia among the first 4000 AIMS incident reports. Identified aetiological factors were grouped into five categories: (1) anaesthetic technique (11 cases with this category alone; 32 with this and one or more of the other categories, representing 25% of all 129 cardiac arrests); (2) drug related (16; 32, 25%); (3) associated with surgical procedure (9; 29, 22%); (4) associated with pre-existing medical or surgical disease (30; 82, 64%); (5) unknown (8; 14, 11%). The "real life" presentation and management of cardiac arrest in association with anaesthesia differs substantially from that detailed in general published guidelines. Cardiac rhythms at the time were sinus bradycardia (23%); asystole (22%); tachycardia/ventricular tachycardia/ventricular fibrillation (14%); and normal (7%), with a further third unknown. Details of treatment were recorded in 110 reports; modalities employed included cardiac compression (72%); adrenaline (61%); 100% oxygen (58%); atropine (38%); intravenous fluids (25%), and electrical defibrillation (17%). There

Robotic Applications in Cardiac Surgery

Directory of Open Access Journals (Sweden)

Alan P. Kypson

2008-11-01

Full Text Available Traditionally, cardiac surgery has been performed through a median sternotomy, which allows the surgeon generous access to the heart and surrounding great vessels. As a paradigm shift in the size and location of incisions occurs in cardiac surgery, new methods have been developed to allow the surgeon the same amount of dexterity and accessibility to the heart in confined spaces and in a less invasive manner. Initially, long instruments without pivot points were used, however, more recent robotic telemanipulation systems have been applied that allow for improved dexterity, enabling the surgeon to perform cardiac surgery from a distance not previously possible. In this rapidly evolving field, we review the recent history and clinical results of using robotics in cardiac surgery.

Pre-transplantation specification of stem cells to cardiac lineage for regeneration of cardiac tissue.

Science.gov (United States)

Mayorga, Maritza; Finan, Amanda; Penn, Marc

2009-03-01

Myocardial infarction (MI) is a lead cause of mortality in the Western world. Treatment of acute MI is focused on restoration of antegrade flow which inhibits further tissue loss, but does not restore function to damaged tissue. Chronic therapy for injured myocardial tissue involves medical therapy that attempts to minimize pathologic remodeling of the heart. End stage therapy for chronic heart failure (CHF) involves inotropic therapy to increase surviving cardiac myocyte function or mechanical augmentation of cardiac performance. Not until the point of heart transplantation, a limited resource at best, does therapy focus on the fundamental problem of needing to replace injured tissue with new contractile tissue. In this setting, the potential for stem cell therapy has garnered significant interest for its potential to regenerate or create new contractile cardiac tissue. While to date adult stem cell therapy in clinical trials has suggested potential benefit, there is waning belief that the approaches used to date lead to regeneration of cardiac tissue. As the literature has better defined the pathways involved in cardiac differentiation, preclinical studies have suggested that stem cell pretreatment to direct stem cell differentiation prior to stem cell transplantation may be a more efficacious strategy for inducing cardiac regeneration. Here we review the available literature on pre-transplantation conditioning of stem cells in an attempt to better understand stem cell behavior and their readiness in cell-based therapy for myocardial regeneration.

[Role of cardiac magnetic resonance in cardiac involvement of Fabry disease].

Science.gov (United States)

Serra, Viviana M; Barba, Miguel Angel; Torrá, Roser; Pérez De Isla, Leopoldo; López, Mónica; Calli, Andrea; Feltes, Gisela; Torras, Joan; Valverde, Victor; Zamorano, José L

2010-09-04

Fabry disease is a hereditary disorder. Clinical manifestations are multisystemic. The majority of the patients remain undiagnosed until late in life, when alterations could be irreversible. Early detection of cardiac symptoms is of major interest in Fabry's disease (FD) in order to gain access to enzyme replacement therapy. Echo-Doppler tissular imaging (TDI) has been used as a cardiologic early marker in FD. This study is intended to determine whether the cardiac magnetic resonance is as useful tool as TDI for the early detection of cardiac affectation in FD. Echocardiography, tissue Doppler and Cardio magnetic resonance was performed in 20 patients with confirmed Fabry Disease. Left ventricular hypertrophy was defined as septum and left ventricular posterior wall thickness ≥12 mm. An abnormal TDI velocity was defined as (Sa), (Ea) and/or (Aa) velocities gadolinium-enhanced images sequences were obtained using magnetic resonance. Twenty patients included in the study were divided into three groups: 1. Those without left ventricular hypertrophy nor tissue Doppler impairment 2. Those without left ventricular hypertrophy and tissue Doppler impairment 3. Those with left ventricular hypertrophy and Tissue Doppler impairment. Late gadolinium enhancement was found in only one patient, who has already altered DTI and LVH. Tissue Doppler imaging (TDI) is the only diagnostic tool able to provide early detection of cardiac affectation in patients with FD. Magnetic resonance provides information of the disease severity in patients with LVH, but can not be used as an early marker of cardiac disease in patients with FD. However MRI could be of great value for diagnostic stratification. Copyright © 2009 Elsevier España, S.L. All rights reserved.

Mathematical Models of Cardiac Pacemaking Function

Science.gov (United States)

Li, Pan; Lines, Glenn T.; Maleckar, Mary M.; Tveito, Aslak

2013-10-01

Over the past half century, there has been intense and fruitful interaction between experimental and computational investigations of cardiac function. This interaction has, for example, led to deep understanding of cardiac excitation-contraction coupling; how it works, as well as how it fails. However, many lines of inquiry remain unresolved, among them the initiation of each heartbeat. The sinoatrial node, a cluster of specialized pacemaking cells in the right atrium of the heart, spontaneously generates an electro-chemical wave that spreads through the atria and through the cardiac conduction system to the ventricles, initiating the contraction of cardiac muscle essential for pumping blood to the body. Despite the fundamental importance of this primary pacemaker, this process is still not fully understood, and ionic mechanisms underlying cardiac pacemaking function are currently under heated debate. Several mathematical models of sinoatrial node cell membrane electrophysiology have been constructed as based on different experimental data sets and hypotheses. As could be expected, these differing models offer diverse predictions about cardiac pacemaking activities. This paper aims to present the current state of debate over the origins of the pacemaking function of the sinoatrial node. Here, we will specifically review the state-of-the-art of cardiac pacemaker modeling, with a special emphasis on current discrepancies, limitations, and future challenges.

Contribution of cardiac and extra-cardiac disease burden to risk of cardiovascular outcomes varies by ejection fraction in heart failure

DEFF Research Database (Denmark)

Wolsk, Emil; Claggett, Brian; Køber, Lars

2018-01-01

AIMS: Patients with heart failure (HF) often have multiple co-morbidities that contribute to the risk of adverse cardiovascular (CV) and non-CV outcomes. We assessed the relative contribution of cardiac and extra-cardiac disease burden and demographic factors to CV outcomes in HF patients...... Association class, systolic blood pressure, time since HF diagnosis, HF medication use), extra-cardiac (body mass index, creatinine, diabetes mellitus, chronic obstructive pulmonary disease, smoker), and demographic (age, gender) categories, and calculated subscores for each patient representing the burden......EF patients (PAR: 76% cardiac disease vs. 58% extra-cardiac disease, P vs. 49% extra-cardiac disease, P

Directed fusion of cardiac spheroids into larger heterocellular microtissues enables investigation of cardiac action potential propagation via cardiac fibroblasts

Science.gov (United States)

Markes, Alexander R.; Okundaye, Amenawon O.; Qu, Zhilin; Mende, Ulrike; Choi, Bum-Rak

2018-01-01

Multicellular spheroids generated through cellular self-assembly provide cytoarchitectural complexities of native tissue including three-dimensionality, extensive cell-cell contacts, and appropriate cell-extracellular matrix interactions. They are increasingly suggested as building blocks for larger engineered tissues to achieve shapes, organization, heterogeneity, and other biomimetic complexities. Application of these tissue culture platforms is of particular importance in cardiac research as the myocardium is comprised of distinct but intermingled cell types. Here, we generated scaffold-free 3D cardiac microtissue spheroids comprised of cardiac myocytes (CMs) and/or cardiac fibroblasts (CFs) and used them as building blocks to form larger microtissues with different spatial distributions of CMs and CFs. Characterization of fusing homotypic and heterotypic spheroid pairs revealed an important influence of CFs on fusion kinetics, but most strikingly showed rapid fusion kinetics between heterotypic pairs consisting of one CF and one CM spheroid, indicating that CMs and CFs self-sort in vitro into the intermixed morphology found in the healthy myocardium. We then examined electrophysiological integration of fused homotypic and heterotypic microtissues by mapping action potential propagation. Heterocellular elongated microtissues which recapitulate the disproportionate CF spatial distribution seen in the infarcted myocardium showed that action potentials propagate through CF volumes albeit with significant delay. Complementary computational modeling revealed an important role of CF sodium currents and the spatial distribution of the CM-CF boundary in action potential conduction through CF volumes. Taken together, this study provides useful insights for the development of complex, heterocellular engineered 3D tissue constructs and their engraftment via tissue fusion and has implications for arrhythmogenesis in cardiac disease and repair. PMID:29715271

Directed fusion of cardiac spheroids into larger heterocellular microtissues enables investigation of cardiac action potential propagation via cardiac fibroblasts.

Directory of Open Access Journals (Sweden)

Tae Yun Kim

Full Text Available Multicellular spheroids generated through cellular self-assembly provide cytoarchitectural complexities of native tissue including three-dimensionality, extensive cell-cell contacts, and appropriate cell-extracellular matrix interactions. They are increasingly suggested as building blocks for larger engineered tissues to achieve shapes, organization, heterogeneity, and other biomimetic complexities. Application of these tissue culture platforms is of particular importance in cardiac research as the myocardium is comprised of distinct but intermingled cell types. Here, we generated scaffold-free 3D cardiac microtissue spheroids comprised of cardiac myocytes (CMs and/or cardiac fibroblasts (CFs and used them as building blocks to form larger microtissues with different spatial distributions of CMs and CFs. Characterization of fusing homotypic and heterotypic spheroid pairs revealed an important influence of CFs on fusion kinetics, but most strikingly showed rapid fusion kinetics between heterotypic pairs consisting of one CF and one CM spheroid, indicating that CMs and CFs self-sort in vitro into the intermixed morphology found in the healthy myocardium. We then examined electrophysiological integration of fused homotypic and heterotypic microtissues by mapping action potential propagation. Heterocellular elongated microtissues which recapitulate the disproportionate CF spatial distribution seen in the infarcted myocardium showed that action potentials propagate through CF volumes albeit with significant delay. Complementary computational modeling revealed an important role of CF sodium currents and the spatial distribution of the CM-CF boundary in action potential conduction through CF volumes. Taken together, this study provides useful insights for the development of complex, heterocellular engineered 3D tissue constructs and their engraftment via tissue fusion and has implications for arrhythmogenesis in cardiac disease and repair.

Plasma membrane characterization, by scanning electron microscopy, of multipotent myoblasts-derived populations sorted using dielectrophoresis.

Science.gov (United States)

Muratore, Massimo; Mitchell, Steve; Waterfall, Martin

2013-09-06

Multipotent progenitor cells have shown promise for use in biomedical applications and regenerative medicine. The implementation of such cells for clinical application requires a synchronized, phenotypically and/or genotypically, homogenous cell population. Here we have demonstrated the implementation of a biological tag-free dielectrophoretic device used for discrimination of multipotent myoblastic C2C12 model. The multipotent capabilities in differentiation, for these cells, diminishes with higher passage number, so for cultures above 70 passages only a small percentage of cells is able to differentiate into terminal myotubes. In this work we demonstrated that we could recover, above 96% purity, specific cell types from a mixed population of cells at high passage number without any biological tag using dielectrophoresis. The purity of the samples was confirmed by cytometric analysis using the cell specific marker embryonic myosin. To further investigate the dielectric properties of the cell plasma membrane we co-culture C2C12 with similar size, when in suspension, GFP-positive fibroblast as feeder layer. The level of separation between the cell types was above 98% purity which was confirmed by flow cytometry. These levels of separation are assumed to account for cell size and for the plasma membrane morphological differences between C2C12 and fibroblast unrelated to the stages of the cell cycle which was assessed by immunofluorescence staining. Plasma membrane conformational differences were further confirmed by scanning electron microscopy. Copyright © 2013 Elsevier Inc. All rights reserved.

Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 undergo the stochastic cardiomyogenic fate and behave like transient amplifying cells

International Nuclear Information System (INIS)

Yamada, Yoji; Sakurada, Kazuhiro; Takeda, Yukiji; Gojo, Satoshi; Umezawa, Akihiro

2007-01-01

Bone marrow-derived stromal cells can give rise to cardiomyocytes as well as adipocytes, osteocytes, and chondrocytes in vitro. The existence of mesenchymal stem cells has been proposed, but it remains unclear if a single-cell-derived stem cell stochastically commits toward a cardiac lineage. By single-cell marking, we performed a follow-up study of individual cells during the differentiation of 9-15c mesenchymal stromal cells derived from bone marrow cells. Three types of cells, i.e., cardiac myoblasts, cardiac progenitors and multipotent stem cells were differentiated from a single cell, implying that cardiomyocytes are generated stochastically from a single-cell-derived stem cell. We also demonstrated that overexpression of Csx/Nkx2.5 and GATA4, precardiac mesodermal transcription factors, enhanced cardiomyogenic differentiation of 9-15c cells, and the frequency of cardiomyogenic differentiation was increased by co-culturing with fetal cardiomyocytes. Single-cell-derived mesenchymal stem cells overexpressing Csx/Nkx2.5 and GATA4 behaved like cardiac transient amplifying cells, and still retained their plasticity in vivo

Physiologic stress interventions in cardiac imaging

International Nuclear Information System (INIS)

Buda, A.J.

1985-01-01

Physiologic stress interventions are designed to assess the reserve capability of coronary flow and myocardial function. In the normal individual, a sufficiently intense physiologic stress may increase coronary flow and cardiac output by 500% to 600%. However, in patients with cardiac disease, these reserve responses may be absent, or considerably blunted. Thus, physiologic stress testing has proved extremely helpful in detecting cardiac abnormalities when resting cardiac function appears normal. Although dynamic exercise remains the standard approach to physiologic stress testing, a number of other interventions have been used, including: (1) isometric exercise, (2) atrial pacing, (3) cold pressor testing, (4) postextrasystolic potentiation, (5) volume loading, and (6) negative intrathoracic pressure. Each of these may be considered an alternative physiologic intervention whenever dynamic exercise is not feasible. These alternative approaches are important since, in our experience, 20% to 30% of subjects are unable to perform dynamic exercise, or exercise inadequately to produce a sufficiently intense cardiac stress. This chapter reviews physiologic considerations, indications, contraindications, protocols, and results of these physiologic stress interventions when used in combination with cardiac radionuclide procedures

Raf-mediated cardiac hypertrophy in adult Drosophila

Directory of Open Access Journals (Sweden)

Lin Yu

2013-07-01

In response to stress and extracellular signals, the heart undergoes a process called cardiac hypertrophy during which cardiomyocytes increase in size. If untreated, cardiac hypertrophy can progress to overt heart failure that causes significant morbidity and mortality. The identification of molecular signals that cause or modify cardiomyopathies is necessary to understand how the normal heart progresses to cardiac hypertrophy and heart failure. Receptor tyrosine kinase (RTK signaling is essential for normal human cardiac function, and the inhibition of RTKs can cause dilated cardiomyopathies. However, neither investigations of activated RTK signaling pathways nor the characterization of hypertrophic cardiomyopathy in the adult fly heart has been previously described. Therefore, we developed strategies using Drosophila as a model to circumvent some of the complexities associated with mammalian models of cardiovascular disease. Transgenes encoding activated EGFRA887T, Ras85DV12 and Ras85DV12S35, which preferentially signal to Raf, or constitutively active human or fly Raf caused hypertrophic cardiomyopathy as determined by decreased end diastolic lumen dimensions, abnormal cardiomyocyte fiber morphology and increased heart wall thicknesses. There were no changes in cardiomyocyte cell numbers. Additionally, activated Raf also induced an increase in cardiomyocyte ploidy compared with control hearts. However, preventing increases in cardiomyocyte ploidy using fizzy-related (Fzr RNAi did not rescue Raf-mediated cardiac hypertrophy, suggesting that Raf-mediated polyploidization is not required for cardiac hypertrophy. Similar to mammals, the cardiac-specific expression of RNAi directed against MEK or ERK rescued Raf-mediated cardiac hypertrophy. However, the cardiac-specific expression of activated ERKD334N, which promotes hyperplasia in non-cardiac tissues, did not cause myocyte hypertrophy. These results suggest that ERK is necessary, but not sufficient, for Raf

Cardiac anatomy and physiology: a review.

Science.gov (United States)

Gavaghan, M

1998-04-01

This article reviews the normal anatomy and physiology of the heart. Understanding the normal anatomic and physiologic relationships described in this article will help perioperative nurses care for patients who are undergoing cardiac procedures. Such knowledge also assists nurses in educating patients about cardiac procedures and about activities that can prevent, reverse, or improve cardiac illness.

Usefulness of cardiac 125I-metaiodobenzylguanidine uptake for evaluation of cardiac sympathetic nerve abnormalities in diabetic rats

International Nuclear Information System (INIS)

Abe, Nanami; Kashiwagi, Atsunori; Shigeta, Yukio

1992-01-01

We investigated cardiac sympathetic nerve abnormalities in streptozocin-induced diabetic rats using 125 I-metaiodobenzylguanidine (MIBG). The radioactivity ratio of cardiac tissue to 1 ml blood (H/B) was used as an index of cardiac MIBG uptake. Cardiac 125 I-MIBG uptake (H/B) in 4-, 8- and 20-wk diabetic rats was 48% lower than that in control rats. Similar results were obtained even when the data were corrected for g wet tissue weight. Although there was no improvement in H/B following 2-wk insulin treatment, the H/B ratio increased significantly, to 85% of control levels, following 4 wk insulin treatment indicating the reversibility of impaired MIBG uptake in diabetic rats. In vivo reserpine treatment resulted in a 50% reduction in the H/B value in control rats. However, the treatment did not significantly suppress uptake in diabetic rats. Cardiac norepinephrine content in both * 4- and ** 8-wk diabetic rats was significantly ( * p ** p 125 I-MIBG in diabetic rats is significantly impaired due to cardiac sympathetic nerve abnormalities. These abnormalities are reversible, however, dependent on the diabetic state. (author)

Cardiac troponins--Translational biomarkers in cardiology: Theory and practice of cardiac troponin high-sensitivity assays.

Science.gov (United States)

Adamcova, Michaela; Popelova-Lencova, Olga; Jirkovsky, Eduard; Simko, Fedor; Gersl, Vladimir; Sterba, Martin

2016-01-01

Tn is a unique translational biomarker in cardiology whose potential has not been diminished in the new era of high sensitive assays. cTns can be valuable markers in cardiac diseases as well as in infectious diseases and respiratory diseases. Furthermore, the role of cTns is growing in the routine evaluation of cardioxicity and in determining the efficacy/safety ratio of novel cardioprotective strategies in clinical settings. cTns can detect myocardial injury not only in a wide spectrum of laboratory animals in experimental studies in vivo, but also in isolated heart models or cardiomyocytes in vitro. The crucial issue regarding the cross-species usage of cardiac troponin investigation remains the choice of cardiac troponin testing. This review summarizes the recent proteomic data on aminoacid sequences of cTnT and cTnI in various species, as well as selected analytical characteristics of human cardiac troponin high-sensitivity assays. Due to the highly phylogenetically conserved structure of troponins, the same bioindicator can be investigated using the same method in both clinical and experimental cardiology, thus contributing to a better understanding of the pathogenesis of cardiac diseases as well as to increased effectiveness of troponin use in clinical practice. Measuring cardiac troponins using commercially available human high-sensitivity cardiac troponin tests with convenient antibodies selected on the basis of adequate proteomic knowledge can solve many issues which would otherwise be difficult to address in clinical settings for various ethical and practical reasons. Our survey could help elaborate the practical guidelines for optimizing the choice of cTns assay in cardiology. © 2016 International Union of Biochemistry and Molecular Biology.

Temperature-responsive poly(ε-caprolactone) cell culture platform with dynamically tunable nano-roughness and elasticity for control of myoblast morphology.

Science.gov (United States)

Uto, Koichiro; Ebara, Mitsuhiro; Aoyagi, Takao

2014-01-21

We developed a dynamic cell culture platform with dynamically tunable nano-roughness and elasticity. Temperature-responsive poly(ε-caprolactone) (PCL) films were successfully prepared by crosslinking linear and tetra-branched PCL macromonomers. By optimizing the mixing ratios, the crystal-amorphous transition temperature (Tm) of the crosslinked film was adjusted to the biological relevant temperature (~33 °C). While the crosslinked films are relatively stiff (50 MPa) below the Tm, they suddenly become soft (1 MPa) above the Tm. Correspondingly, roughness of the surface was decreased from 63.4-12.4 nm. It is noted that the surface wettability was independent of temperature. To investigate the role of dynamic surface roughness and elasticity on cell adhesion, cells were seeded on PCL films at 32 °C. Interestingly, spread myoblasts on the film became rounded when temperature was suddenly increased to 37 °C, while significant changes in cell morphology were not observed for fibroblasts. These results indicate that cells can sense dynamic changes in the surrounding environment but the sensitivity depends on cell types.

ASCI 2010 contrast media guideline for cardiac imaging: a report of the Asian Society of Cardiovascular Imaging cardiac computed tomography and cardiac magnetic resonance imaging guideline working group

Science.gov (United States)

Kitagawa, Kakuya; Tsai, I-Chen; Chan, Carmen; Yu, Wei; Yong, Hwan Seok; Choi, Byoung Wook

2010-01-01

The use of contrast media for cardiac imaging becomes increasing as the widespread of cardiac CT and cardiac MR. A radiologist needs to carefully consider the indication and the injection protocol of contrast media to be used as well as the possibility of adverse effect. There are several guidelines for contrast media in western countries. However, these are focusing the adverse effect of contrast media. The Asian Society of Cardiovascular Imaging, the only society dedicated to cardiovascular imaging in Asia, formed a Working Group and created a guideline, which summarizes the integrated knowledge of contrast media for cardiac imaging. In cardiac imaging, coronary artery evaluation is feasible by non-contrast MR angiography, which can be an alternative examination in high risk patients for the use of iodine contrast media. Furthermore, the body habitus of Asian patients is usually smaller than that of their western counterparts. This necessitates modifications in the injection protocol and in the formula for calculation of estimated glomerular filtration rate. This guideline provided fundamental information for the use of contrast media for Asian patients in cardiac imaging. PMID:20931289

Acupuncture therapy related cardiac injury.

Science.gov (United States)

Li, Xue-feng; Wang, Xian

2013-12-01

Cardiac injury is the most serious adverse event in acupuncture therapy. The causes include needling chest points near the heart, the cardiac enlargement and pericardial effusion that will enlarge the projected area on the body surface and make the proper depth of needling shorter, and the incorrect needling method of the points. Therefore, acupuncture practitioners must be familiar with the points of the heart projected area on the chest and the correct needling methods in order to reduce the risk of acupuncture therapy related cardiac injury.

Mathematical Models of Cardiac Pacemaking Function

Directory of Open Access Journals (Sweden)

Pan eLi

2013-10-01

Full Text Available Over the past half century, there has been intense and fruitful interaction between experimental and computational investigations of cardiac function. This interaction has, for example, led to deep understanding of cardiac excitation-contraction coupling; how it works, as well as how it fails. However, many lines of inquiry remain unresolved, among them the initiation of each heartbeat. The sinoatrial node, a cluster of specialized pacemaking cells in the right atrium of the heart, spontaneously generates an electro-chemical wave that spreads through the atria and through the cardiac conduction system to the ventricles, initiating the contraction of cardiac muscle essential for pumping blood to the body. Despite the fundamental importance of this primary pacemaker, this process is still not fully understood, and ionic mechanisms underlying cardiac pacemaking function are currently under heated debate. Several mathematical models of sinoatrial node cell membrane electrophysiology have been constructed as based on different experimental data sets and hypotheses. As could be expected, these differing models offer diverse predictions about cardiac pacemaking activities. This paper aims to present the current state of debate over the origins of the pacemaking function of the sinoatrial node. Here, we will specifically review the state-of-the-art of cardiac pacemaker modeling, with a special emphasis on current discrepancies, limitations, and future challenges.

Transcriptional profile of isoproterenol-induced cardiomyopathy and comparison to exercise-induced cardiac hypertrophy and human cardiac failure

Directory of Open Access Journals (Sweden)

McIver Lauren J

2009-12-01

Full Text Available Abstract Background Isoproterenol-induced cardiac hypertrophy in mice has been used in a number of studies to model human cardiac disease. In this study, we compared the transcriptional response of the heart in this model to other animal models of heart failure, as well as to the transcriptional response of human hearts suffering heart failure. Results We performed microarray analyses on RNA from mice with isoproterenol-induced cardiac hypertrophy and mice with exercise-induced physiological hypertrophy and identified 865 and 2,534 genes that were significantly altered in pathological and physiological cardiac hypertrophy models, respectively. We compared our results to 18 different microarray data sets (318 individual arrays representing various other animal models and four human cardiac diseases and identified a canonical set of 64 genes that are generally altered in failing hearts. We also produced a pairwise similarity matrix to illustrate relatedness of animal models with human heart disease and identified ischemia as the human condition that most resembles isoproterenol treatment. Conclusion The overall patterns of gene expression are consistent with observed structural and molecular differences between normal and maladaptive cardiac hypertrophy and support a role for the immune system (or immune cell infiltration in the pathology of stress-induced hypertrophy. Cross-study comparisons such as the results presented here provide targets for further research of cardiac disease that might generally apply to maladaptive cardiac stresses and are also a means of identifying which animal models best recapitulate human disease at the transcriptional level.

47. A cardiac center experience with Brugada syndrome who survived sudden cardiac death

Directory of Open Access Journals (Sweden)

I. Suliman

2016-07-01

Full Text Available Brugada syndrome is a heritable arrhythmia syndrome that is characterized by an electrocardiographic pattern consisting of coved-type ST-segment elevation (2 mm followed by a negative T wave in the right precordial leads, V1 through V3 (often referred to as type 1 Brugada electrocardiographic pattern, here we describe 3 cases of Brugada who survived sudden cardiac death (SCD cardiac center experience with survived Brugada syndrome patients – case series. First Case: The Father 45 years old male, presented in 2005 after involvement in unprovoked motor vehicle accident, the patient was the driver who lost consciousness and rushed to the hospital. On arrival to our ER and putting the patient on the bed, the ER doctor observed a brief episode of VF on the monitor. The patient was taken to the catheterization Lab , his coronaries were normal. The diagnosis of Brugada was established and the patient received a defibrillator. At That Time all family members were screened and were negative. Second Case: The Son of the first patient 5 years later his 23 years old male rushed to our ER after he lost consciousness, he was passenger in the car of his friend. Third Case: The pilot A military pilot aged a male 35 years old was in very good health when he lost consciousness and brought to the hospital after resuscitation in 2005. He had full invasive cardiac evaluation, subsequently he received a defibrillator in the same admission period, till 2015 he is doing fine. Brugada syndrome is associated with high tendency for sudden cardiac death. In our three cases the first clinical presentation was survived sudden cardiac death (SCD and all three male patients survived. We did not encounter a female patient who survived sudden cardiac death.

Evaluating the Cancer Therapeutic Potential of Cardiac Glycosides

Directory of Open Access Journals (Sweden)

José Manuel Calderón-Montaño

2014-01-01

Full Text Available Cardiac glycosides, also known as cardiotonic steroids, are a group of natural products that share a steroid-like structure with an unsaturated lactone ring and the ability to induce cardiotonic effects mediated by a selective inhibition of the Na+/K+-ATPase. Cardiac glycosides have been used for many years in the treatment of cardiac congestion and some types of cardiac arrhythmias. Recent data suggest that cardiac glycosides may also be useful in the treatment of cancer. These compounds typically inhibit cancer cell proliferation at nanomolar concentrations, and recent high-throughput screenings of drug libraries have therefore identified cardiac glycosides as potent inhibitors of cancer cell growth. Cardiac glycosides can also block tumor growth in rodent models, which further supports the idea that they have potential for cancer therapy. Evidence also suggests, however, that cardiac glycosides may not inhibit cancer cell proliferation selectively and the potent inhibition of tumor growth induced by cardiac glycosides in mice xenografted with human cancer cells is probably an experimental artifact caused by their ability to selectively kill human cells versus rodent cells. This paper reviews such evidence and discusses experimental approaches that could be used to reveal the cancer therapeutic potential of cardiac glycosides in preclinical studies.

[Experimental therapy of cardiac remodeling with quercetin-containing drugs].

Science.gov (United States)

Kuzmenko, M A; Pavlyuchenko, V B; Tumanovskaya, L V; Dosenko, V E; Moybenko, A A

2013-01-01

It was shown that continuous beta-adrenergic hyperstimulation resulted in cardiac function disturbances and fibrosis of cardiac tissue. Treatment with quercetin-containing drugs, particularly, water-soluble corvitin and tableted quertin exerted favourable effect on cardiac hemodynamics, normalized systolic and diastolic function in cardiac remodeling, induced by sustained beta-adrenergic stimulation. It was estimated that conducted experimental therapy limited cardiac fibrosis area almost three-fold, that could be associated with first and foremost improved cardiac distensibility, characteristics of diastolic and also pump function in cardiac remodeling.

Cardiac imaging. A multimodality approach

International Nuclear Information System (INIS)

Thelen, Manfred; Erbel, Raimund; Kreitner, Karl-Friedrich; Barkhausen, Joerg

2009-01-01

An excellent atlas on modern diagnostic imaging of the heart Written by an interdisciplinary team of experts, Cardiac Imaging: A Multimodality Approach features an in-depth introduction to all current imaging modalities for the diagnostic assessment of the heart as well as a clinical overview of cardiac diseases and main indications for cardiac imaging. With a particular emphasis on CT and MRI, the first part of the atlas also covers conventional radiography, echocardiography, angiography and nuclear medicine imaging. Leading specialists demonstrate the latest advances in the field, and compare the strengths and weaknesses of each modality. The book's second part features clinical chapters on heart defects, endocarditis, coronary heart disease, cardiomyopathies, myocarditis, cardiac tumors, pericardial diseases, pulmonary vascular diseases, and diseases of the thoracic aorta. The authors address anatomy, pathophysiology, and clinical features, and evaluate the various diagnostic options. Key features: - Highly regarded experts in cardiology and radiology off er image-based teaching of the latest techniques - Readers learn how to decide which modality to use for which indication - Visually highlighted tables and essential points allow for easy navigation through the text - More than 600 outstanding images show up-to-date technology and current imaging protocols Cardiac Imaging: A Multimodality Approach is a must-have desk reference for cardiologists and radiologists in practice, as well as a study guide for residents in both fields. It will also appeal to cardiac surgeons, general practitioners, and medical physicists with a special interest in imaging of the heart. (orig.)

Cross sectional imaging of cardiac tumors

International Nuclear Information System (INIS)

Maksimovic, R.

2012-01-01

Full text: Primary cardiac tumors are a rare entity whose incidence, according to surgery and autopsy reports, is 0.3% to 0.7% of all cardiac tumors. Metastasis to the heart from other primary cancers is 30 times more common. Only 25% of primary cardiac tumors are malignant, and, of these, 75% are sarcomas. Malignant primary cardiac sarcomas are usually located in the right atrium and are most commonly angiosarcoma. In the left atrium, the most common malignant tumors are pleomorphic sarcoma and leiomyosarcoma. Symptom presentation for cardiac tumors is quite varied, but it is dependent upon tumor location and size, rather than upon histologic characteristics. Presentation includes congestive heart failure from intracardiac obstruction, systemic embolization, constitutional symptoms, and arrhythmias. Left atrial sarcomas tend to be more solid and less infiltrative than right-sided sarcomas; consequently, they tend to metastasize later. They usually present with symptoms of blood-flow obstruction and substantial, life-threatening congestive heart failure. Right-sided cardiac tumors are usually malignant and appear as bulky, infiltrative masses that grow in an outward pattern. These are usually fast-growing tumors that metastasize early and do not present with congestive heart failure until late in the disease. The diagnosis of cardiac tumors relies heavily on the use of multiple imaging techniques, including cardiac computed tomography (CT), cardiovascular magnetic resonance (CMR), and echocardiography. Important imaging data to collect include information on the size of the intracardiac mass, the mobility of the mass (an important predictor of prognosis and embolic potential), myocardial invasion, and cardiac chamber location. These factors will provide the means to diagnosis and prognosis. Other important data to collect include the mechanism of tumor implantation, the relationship of the tumor with adjacent structures, the surgeon route of access to the heart

A model of survival following pre-hospital cardiac arrest based on the Victorian Ambulance Cardiac Arrest Register.

Science.gov (United States)

Fridman, Masha; Barnes, Vanessa; Whyman, Andrew; Currell, Alex; Bernard, Stephen; Walker, Tony; Smith, Karen L

2007-11-01

This study describes the epidemiology of sudden cardiac arrest patients in Victoria, Australia, as captured via the Victorian Ambulance Cardiac Arrest Register (VACAR). We used the VACAR data to construct a new model of out-of-hospital cardiac arrest (OHCA), which was specified in accordance with observed trends. All cases of cardiac arrest in Victoria that were attended by Victorian ambulance services during the period of 2002-2005. Overall survival to hospital discharge was 3.8% among 18,827 cases of OHCA. Survival was 15.7% among 1726 bystander witnessed, adult cardiac arrests of presumed cardiac aetiology, presenting in ventricular fibrillation or ventricular tachycardia (VF/VT), where resuscitation was attempted. In multivariate logistic regression analysis, bystander CPR, cardiac arrest (CA) location, response time, age and sex were predictors of VF/VT, which, in turn, was a strong predictor of survival. The same factors that affected VF/VT made an additional contribution to survival. However, for bystander CPR, CA location and response time this additional contribution was limited to VF/VT patients only. There was no detectable association between survival and age younger than 60 years or response time over 15min. The new model accounts for relationships among predictors of survival. These relationships indicate that interventions such as reduced response times and bystander CPR act in multiple ways to improve survival.

Sudden Cardiac Arrest during Participation in Competitive Sports.

Science.gov (United States)

Landry, Cameron H; Allan, Katherine S; Connelly, Kim A; Cunningham, Kris; Morrison, Laurie J; Dorian, Paul

2017-11-16

The incidence of sudden cardiac arrest during participation in sports activities remains unknown. Preparticipation screening programs aimed at preventing sudden cardiac arrest during sports activities are thought to be able to identify at-risk athletes; however, the efficacy of these programs remains controversial. We sought to identify all sudden cardiac arrests that occurred during participation in sports activities within a specific region of Canada and to determine their causes. In this retrospective study, we used the Rescu Epistry cardiac arrest database (which contains records of every cardiac arrest attended by paramedics in the network region) to identify all out-of-hospital cardiac arrests that occurred from 2009 through 2014 in persons 12 to 45 years of age during participation in a sport. Cases were adjudicated as sudden cardiac arrest (i.e., having a cardiac cause) or as an event resulting from a noncardiac cause, on the basis of records from multiple sources, including ambulance call reports, autopsy reports, in-hospital data, and records of direct interviews with patients or family members. Over the course of 18.5 million person-years of observation, 74 sudden cardiac arrests occurred during participation in a sport; of these, 16 occurred during competitive sports and 58 occurred during noncompetitive sports. The incidence of sudden cardiac arrest during competitive sports was 0.76 cases per 100,000 athlete-years, with 43.8% of the athletes surviving until they were discharged from the hospital. Among the competitive athletes, two deaths were attributed to hypertrophic cardiomyopathy and none to arrhythmogenic right ventricular cardiomyopathy. Three cases of sudden cardiac arrest that occurred during participation in competitive sports were determined to have been potentially identifiable if the athletes had undergone preparticipation screening. In our study involving persons who had out-of-hospital cardiac arrest, the incidence of sudden cardiac

Impact of Hepatocyte Growth Factor on Skeletal Myoblast Transplantation Late after Myocardial Infarction

Directory of Open Access Journals (Sweden)

Stacy B. O'blenes

2013-01-01

Full Text Available In clinical studies, skeletal myoblast (SKMB transplantation late after myocardial infarction (MI has minimal impact on left ventricular (LV function. This may be related to our previous observation that the extent of SKMB engraftment is minimal in chronic MI when compared to acute MI, which correlates with decreased hepatocyte growth factor (HGF expression, an important regulator of SKMB function. Here, we investigated delivery of exogenous HGF as a strategy for augmenting SKMB engraftment late after MI. Rats underwent SKMB transplantation 4 weeks after coronary ligation. HGF or vehicle control was delivered intravenously during the subsequent 2 weeks. LV function was assessed by MRI before and 2 weeks after SKMB transplantation. We evaluated HGF delivery, SKMB engraftment, and expression of genes associated with post-MI remodeling. Serum HGF was 6.2 ± 2.4 ng/mL after 2 weeks of HGF infusion (n = 7, but undetectable in controls (n = 7. LV end-diastolic volume and ejection fraction did not improve with HGF treatment (321 ± 27 mm 3 , 42% ± 2% vs. 285 ± 33 mm 3 , 43% ± 2%, HGF vs. control. MIs were larger in HGF-treated animals (50 ± 7 vs. 30 ± 6 mm 3 , P = 0.046, but the volume of engrafted SKMBs or percentage of MIs occupied by SKMBs did not increase with HGF (1.7 ± 0.3 mm 3 , 4.7% ± 1.9% vs. 1.4 ± 0.4 mm 3 , 5.3% ± 1.6%, HGF vs. control. Expression of genes associated with post-infarction remodeling was not altered by HGF. Delivery of exogenous HGF failed to augment SKMB engraftment and functional recovery in chronic MI. Expression of genes associated with LV remodeling was not altered by HGF. Alternative strategies to enhance engraftment of SKMB must be explored to optimize the clinical efficacy of SKMB transplantation.

Mitochondrial oxidative stress and cardiac ageing.

Science.gov (United States)

Martín-Fernández, Beatriz; Gredilla, Ricardo

According with different international organizations, cardiovascular diseases are becoming the first cause of death in western countries. Although exposure to different risk factors, particularly those related to lifestyle, contribute to the etiopathogenesis of cardiac disorders, the increase in average lifespan and aging are considered major determinants of cardiac diseases events. Mitochondria and oxidative stress have been pointed out as relevant factors both in heart aging and in the development of cardiac diseases such as heart failure, cardiac hypertrophy and diabetic cardiomyopathy. During aging, cellular processes related with mitochondrial function, such as bioenergetics, apoptosis and inflammation are altered leading to cardiac dysfunction. Increasing our knowledge about the mitochondrial mechanisms related with the aging process, will provide new strategies in order to improve this process, particularly the cardiovascular ones. Copyright © 2017 Sociedad Española de Arteriosclerosis. Publicado por Elsevier España, S.L.U. All rights reserved.

Proteostasis in cardiac health and disease.

Science.gov (United States)

Henning, Robert H; Brundel, Bianca J J M

2017-11-01

The incidence and prevalence of cardiac diseases, which are the main cause of death worldwide, are likely to increase because of population ageing. Prevailing theories about the mechanisms of ageing feature the gradual derailment of cellular protein homeostasis (proteostasis) and loss of protein quality control as central factors. In the heart, loss of protein patency, owing to flaws in genetically-determined design or because of environmentally-induced 'wear and tear', can overwhelm protein quality control, thereby triggering derailment of proteostasis and contributing to cardiac ageing. Failure of protein quality control involves impairment of chaperones, ubiquitin-proteosomal systems, autophagy, and loss of sarcomeric and cytoskeletal proteins, all of which relate to induction of cardiomyocyte senescence. Targeting protein quality control to maintain cardiac proteostasis offers a novel therapeutic strategy to promote cardiac health and combat cardiac disease. Currently marketed drugs are available to explore this concept in the clinical setting.

Home-based versus centre-based cardiac rehabilitation.

Science.gov (United States)

Taylor, Rod S; Dalal, Hayes; Jolly, Kate; Moxham, Tiffany; Zawada, Anna

2010-01-20

The burden of cardiovascular disease world-wide is one of great concern to patients and health care agencies alike. Traditionally centre-based cardiac rehabilitation (CR) programmes are offered to individuals after cardiac events to aid recovery and prevent further cardiac illness. Home-based cardiac rehabilitation programmes have been introduced in an attempt to widen access and participation. To determine the effectiveness of home-based cardiac rehabilitation programmes compared with supervised centre-based cardiac rehabilitation on mortality and morbidity, health-related quality of life and modifiable cardiac risk factors in patients with coronary heart disease. We updated the search of a previous review by searching the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (2007, Issue 4), MEDLINE, EMBASE and CINAHL from 2001 to January 2008. We checked reference lists and sought advice from experts. No language restrictions were applied. Randomised controlled trials (RCTs) that compared centre-based cardiac rehabilitation (e.g. hospital, gymnasium, sports centre) with home-based programmes, in adults with myocardial infarction, angina, heart failure or who had undergone revascularisation. Studies were selected independently by two reviewers, and data extracted by a single reviewer and checked by a second one. Authors were contacted where possible to obtain missing information. Twelve studies (1,938 participants) met the inclusion criteria. The majority of studies recruited a lower risk patient following an acute myocardial infarction (MI) and revascularisation. There was no difference in outcomes of home- versus centre-based cardiac rehabilitation in mortality risk ratio (RR) was1.31 (95% confidence interval (C) 0.65 to 2.66), cardiac events, exercise capacity standardised mean difference (SMD) -0.11 (95% CI -0.35 to 0.13), as well as in modifiable risk factors (systolic blood pressure; diastolic blood pressure; total cholesterol

Digital subtraction angiography in cardiac diseases

International Nuclear Information System (INIS)

Choi, Deuk Lin; Kim, Ki Jeong

1986-01-01

DSA was done in 133 examinations of 128 patients during 2 years consist of 9 examination of IV DSA and 124 examination of selective cardiac DSA after cardiac catheterization. Open heart surgery was performed in 90 patients and 12 patients showed discrepancy between pre-and post operative diagnosis, showing a total 86.7% of diagnostic accuracy with DSA. We experienced the significant reduction in dose of contrast media, 30-40% of dose of conventional cardiac angiography. It is concluded that DSA is useful in the evaluation of septal defects, valvular disease and other congenital heart disease. DSA is an accurate simple and safe method in evaluating of cardiac diseases.

Toll-like receptor 9 mediated responses in cardiac fibroblasts.

Directory of Open Access Journals (Sweden)

Ingrid Kristine Ohm

Full Text Available Altered cardiac Toll-like receptor 9 (TLR9 signaling is important in several experimental cardiovascular disorders. These studies have predominantly focused on cardiac myocytes or the heart as a whole. Cardiac fibroblasts have recently been attributed increasing significance in mediating inflammatory signaling. However, putative TLR9-signaling through cardiac fibroblasts remains non-investigated. Thus, our aim was to explore TLR9-signaling in cardiac fibroblasts and investigate the consequence of such receptor activity on classical cardiac fibroblast cellular functions. Cultivated murine cardiac fibroblasts were stimulated with different TLR9 agonists (CpG A, B and C and assayed for the secretion of inflammatory cytokines (tumor necrosis factor α [TNFα], CXCL2 and interferon α/β. Expression of functional cardiac fibroblast TLR9 was proven as stimulation with CpG B and -C caused significant CXCL2 and TNFα-release. These responses were TLR9-specific as complete inhibition of receptor-stimulated responses was achieved by co-treatment with a TLR9-antagonist (ODN 2088 or chloroquine diphosphate. TLR9-stimulated responses were also found more potent in cardiac fibroblasts when compared with classical innate immune cells. Stimulation of cardiac fibroblasts TLR9 was also found to attenuate migration and proliferation, but did not influence myofibroblast differentiation in vitro. Finally, results from in vivo TLR9-stimulation with subsequent fractionation of specific cardiac cell-types (cardiac myocytes, CD45+ cells, CD31+ cells and cardiac fibroblast-enriched cell-fractions corroborated our in vitro data and provided evidence of differentiated cell-specific cardiac responses. Thus, we conclude that cardiac fibroblast may constitute a significant TLR9 responder cell within the myocardium and, further, that such receptor activity may impact important cardiac fibroblast cellular functions.

A novel fission-independent role of dynamin-related protein 1 in cardiac mitochondrial respiration.

Science.gov (United States)

Zhang, Huiliang; Wang, Pei; Bisetto, Sara; Yoon, Yisang; Chen, Quan; Sheu, Shey-Shing; Wang, Wang

2017-02-01

Mitochondria in adult cardiomyocytes exhibit static morphology and infrequent dynamic changes, despite the high abundance of fission and fusion regulatory proteins in the heart. Previous reports have indicated that fusion proteins may bear functions beyond morphology regulation. Here, we investigated the role of fission protein, dynamin-related protein 1 (DRP1), on mitochondrial respiration regulation in adult cardiomyocytes. By using genetic or pharmacological approaches, we manipulated the activity or protein level of fission and fusion proteins and found they mildly influenced mitochondrial morphology in adult rodent cardiomyocytes, which is in contrast to their significant effect in H9C2 cardiac myoblasts. Intriguingly, inhibiting endogenous DRP1 by dominant-negative DRP1 mutation (K38A), shRNA, or Mdivi-1 suppressed maximal respiration and respiratory control ratio in isolated mitochondria from adult mouse heart or in adult cardiomyocytes from rat. Meanwhile, basal respiration was increased due to increased proton leak. Facilitating mitofusin-mediated fusion by S3 compound, however, failed to inhibit mitochondrial respiration in adult cardiomyocytes. Mechanistically, DRP1 inhibition did not affect the maximal activity of individual respiratory chain complexes or the assembly of supercomplexes. Knocking out cyclophilin D, a regulator of mitochondrial permeability transition pore (mPTP), abolished the effect of DRP1 inhibition on respiration. Finally, DRP1 inhibition decreased transient mPTP-mediated mitochondrial flashes, delayed laser-induced mPTP opening and suppressed mitochondrial reactive oxygen species (ROS). These results uncover a novel non-canonical function of the fission protein, DRP1 in maintaining or positively stimulating mitochondrial respiration, bioenergetics and ROS signalling in adult cardiomyocyte, which is likely independent of morphological changes. Published on behalf of the European Society of Cardiology. All rights reserved. © The

Multimodality imaging to guide cardiac interventional procedures

NARCIS (Netherlands)

Tops, Laurens Franciscus

2010-01-01

In recent years, a number of new cardiac interventional procedures have been introduced. Catheter ablation procedures for atrial fibrillation (AF) have been refined and are now considered a good treatment option in patients with drug-refractory AF. In cardiac pacing, cardiac resynchronization

Thicker three-dimensional tissue from a “symbiotic recycling system” combining mammalian cells and algae

Science.gov (United States)

Haraguchi, Yuji; Kagawa, Yuki; Sakaguchi, Katsuhisa; Matsuura, Katsuhisa; Shimizu, Tatsuya; Okano, Teruo

2017-01-01

In this paper, we report an in vitro co-culture system that combines mammalian cells and algae, Chlorococcum littorale, to create a three-dimensional (3-D) tissue. While the C2C12 mouse myoblasts and rat cardiac cells consumed oxygen actively, intense oxygen production was accounted for by the algae even in the co-culture system. Although cell metabolism within thicker cardiac cell-layered tissues showed anaerobic respiration, the introduction of innovative co-cultivation partially changed the metabolism to aerobic respiration. Moreover, the amount of glucose consumption and lactate production in the cardiac tissues and the amount of ammonia in the culture media decreased significantly when co-cultivated with algae. In the cardiac tissues devoid of algae, delamination was observed histologically, and the release of creatine kinase (CK) from the tissues showed severe cardiac cell damage. On the other hand, the layered cell tissues with algae were observed to be in a good histological condition, with less than one-fifth decline in CK release. The co-cultivation with algae improved the culture condition of the thicker tissues, resulting in the formation of 160 μm-thick cardiac tissues. Thus, the present study proposes the possibility of creating an in vitro “symbiotic recycling system” composed of mammalian cells and algae. PMID:28139713

Thicker three-dimensional tissue from a "symbiotic recycling system" combining mammalian cells and algae.

Science.gov (United States)

Haraguchi, Yuji; Kagawa, Yuki; Sakaguchi, Katsuhisa; Matsuura, Katsuhisa; Shimizu, Tatsuya; Okano, Teruo

2017-01-31

In this paper, we report an in vitro co-culture system that combines mammalian cells and algae, Chlorococcum littorale, to create a three-dimensional (3-D) tissue. While the C2C12 mouse myoblasts and rat cardiac cells consumed oxygen actively, intense oxygen production was accounted for by the algae even in the co-culture system. Although cell metabolism within thicker cardiac cell-layered tissues showed anaerobic respiration, the introduction of innovative co-cultivation partially changed the metabolism to aerobic respiration. Moreover, the amount of glucose consumption and lactate production in the cardiac tissues and the amount of ammonia in the culture media decreased significantly when co-cultivated with algae. In the cardiac tissues devoid of algae, delamination was observed histologically, and the release of creatine kinase (CK) from the tissues showed severe cardiac cell damage. On the other hand, the layered cell tissues with algae were observed to be in a good histological condition, with less than one-fifth decline in CK release. The co-cultivation with algae improved the culture condition of the thicker tissues, resulting in the formation of 160 μm-thick cardiac tissues. Thus, the present study proposes the possibility of creating an in vitro "symbiotic recycling system" composed of mammalian cells and algae.

[Cardiac involvement in Churg-Strauss syndrome].

Science.gov (United States)

Brucato, Antonio; Maestroni, Silvia; Masciocco, Gabriella; Ammirati, Enrico; Bonacina, Edgardo; Pedrotti, Patrizia

2015-09-01

Churg-Strauss syndrome, recently renamed eosinophilic granulomatosis with polyangiitis (EGPA), is a rare form of systemic vasculitis, characterized by disseminated necrotizing vasculitis with extravascular granulomas occurring among patients with asthma and tissue eosinophilia. EGPA is classified as a small and medium-sized vessel vasculitis associated with antineutrophil cytoplasmic antibodies (ANCA) and the hypereosinophilic syndrome. Typical clinical features include asthma, sinusitis, transient pulmonary infiltrates and neuropathy. Blood eosinophils are often >1500/µl or more than 10% on the differential leukocyte count. Blood eosinophils should always be tested in unexplained cardiac disorders, and may normalize even after low doses of corticosteroids. ANCA are positive in 40-60% of cases, mainly anti-myeloperoxidase. Heart involvement occurs in approximately 15-60% of EGPA patients, especially those who are ANCA negative. Any cardiac structure can be involved, and patients present with myocarditis, heart failure, pericarditis, arrhythmia, coronary arteritis, valvulopathy, intracavitary cardiac thrombosis. Although cardiovascular involvement is usually an early manifestation, it can also occur later in the course of the disease. A significant proportion of patients with cardiac involvement is asymptomatic. In the absence of symptoms and major ECG abnormalities, cardiac involvement may be detected in nearly 40% of the patients. All patients with EGPA should be studied not only with a detailed history of cardiac symptoms and ECG, but also with echocardiography; if abnormalities are detected, a cardiac magnetic resonance study should be performed. Coronary angiography and endomyocardial biopsy should be reserved to selected cases. Heart involvement carries a poor prognosis and causes 50% of the deaths of these patients. It is often insidious and underestimated. Optimal therapy is therefore important and based on high-dose corticosteroids plus immunosuppressive

Myocardial ischaemia and the cardiac nervous system.

Science.gov (United States)

Armour, J A

1999-01-01

The intrinsic cardiac nervous system has been classically considered to contain only parasympathetic efferent postganglionic neurones which receive inputs from medullary parasympathetic efferent preganglionic neurones. In such a view, intrinsic cardiac ganglia act as simple relay stations of parasympathetic efferent neuronal input to the heart, the major autonomic control of the heart purported to reside solely in the brainstem and spinal cord. Data collected over the past two decades indicate that processing occurs within the mammalian intrinsic cardiac nervous system which involves afferent neurones, local circuit neurones (interconnecting neurones) as well as both sympathetic and parasympathetic efferent postganglionic neurones. As such, intrinsic cardiac ganglionic interactions represent the organ component of the hierarchy of intrathoracic nested feedback control loops which provide rapid and appropriate reflex coordination of efferent autonomic neuronal outflow to the heart. In such a concept, the intrinsic cardiac nervous system acts as a distributive processor, integrating parasympathetic and sympathetic efferent centrifugal information to the heart in addition to centripetal information arising from cardiac sensory neurites. A number of neurochemicals have been shown to influence the interneuronal interactions which occur within the intrathoracic cardiac nervous system. For instance, pharmacological interventions that modify beta-adrenergic or angiotensin II receptors affect cardiomyocyte function not only directly, but indirectly by influencing the capacity of intrathoracic neurones to regulate cardiomyocytes. Thus, current pharmacological management of heart disease may influence cardiomyocyte function directly as well as indirectly secondary to modifying the cardiac nervous system. This review presents a brief summary of developing concepts about the role of the cardiac nervous system in regulating the normal heart. In addition, it provides some

Network interactions within the canine intrinsic cardiac nervous system: implications for reflex control of regional cardiac function

Science.gov (United States)

Beaumont, Eric; Salavatian, Siamak; Southerland, E Marie; Vinet, Alain; Jacquemet, Vincent; Armour, J Andrew; Ardell, Jeffrey L

2013-01-01

The aims of the study were to determine how aggregates of intrinsic cardiac (IC) neurons transduce the cardiovascular milieu versus responding to changes in central neuronal drive and to determine IC network interactions subsequent to induced neural imbalances in the genesis of atrial fibrillation (AF). Activity from multiple IC neurons in the right atrial ganglionated plexus was recorded in eight anaesthetized canines using a 16-channel linear microelectrode array. Induced changes in IC neuronal activity were evaluated in response to: (1) focal cardiac mechanical distortion; (2) electrical activation of cervical vagi or stellate ganglia; (3) occlusion of the inferior vena cava or thoracic aorta; (4) transient ventricular ischaemia, and (5) neurally induced AF. Low level activity (ranging from 0 to 2.7 Hz) generated by 92 neurons was identified in basal states, activities that displayed functional interconnectivity. The majority (56%) of IC neurons so identified received indirect central inputs (vagus alone: 25%; stellate ganglion alone: 27%; both: 48%). Fifty per cent transduced the cardiac milieu responding to multimodal stressors applied to the great vessels or heart. Fifty per cent of IC neurons exhibited cardiac cycle periodicity, with activity occurring primarily in late diastole into isovolumetric contraction. Cardiac-related activity in IC neurons was primarily related to direct cardiac mechano-sensory inputs and indirect autonomic efferent inputs. In response to mediastinal nerve stimulation, most IC neurons became excessively activated; such network behaviour preceded and persisted throughout AF. It was concluded that stochastic interactions occur among IC local circuit neuronal populations in the control of regional cardiac function. Modulation of IC local circuit neuronal recruitment may represent a novel approach for the treatment of cardiac disease, including atrial arrhythmias. PMID:23818689

Neuromuscular diseases after cardiac transplantation

NARCIS (Netherlands)

Mateen, Farrah J.; van de Beek, Diederik; Kremers, Walter K.; Daly, Richard C.; Edwards, Brooks S.; McGregor, Christopher G. A.; Wijdicks, Eelco F. M.

2009-01-01

BACKGROUND: Cardiac transplantation is a therapeutic option in end-stage heart failure. Peripheral nervous system (PNS) disease is known to occur in cardiac transplant recipients but has not been fully characterized. METHODS: This retrospective cohort review reports the PNS-related concerns of 313

Cardiac arrest – cardiopulmonary resuscitation

Directory of Open Access Journals (Sweden)

Basri Lenjani

2014-01-01

Conclusions: All survivors from cardiac arrest have received appropriate medical assistance within 10 min from attack, which implies that if cardiac arrest occurs near an institution health care (with an opportunity to provide the emergent health care the rate of survival is higher.

Advances in Cell Transplantation Therapy for Diseased Myocardium

Directory of Open Access Journals (Sweden)

Outi M. Villet

2011-01-01

Full Text Available The overall objective of cell transplantation is to repopulate postinfarction scar with contractile cells, thus improving systolic function, and to prevent or to regress the remodeling process. Direct implantation of isolated myoblasts, cardiomyocytes, and bone-marrow-derived cells has shown prospect for improved cardiac performance in several animal models and patients suffering from heart failure. However, direct implantation of cultured cells can lead to major cell loss by leakage and cell death, inappropriate integration and proliferation, and cardiac arrhythmia. To resolve these problems an approach using 3-dimensional tissue-engineered cell constructs has been investigated. Cell engineering technology has enabled scaffold-free sheet development including generation of communication between cell graft and host tissue, creation of organized microvascular network, and relatively long-term survival after in vivo transplantation.

FET-biosensor for cardiac troponin biomarker

Directory of Open Access Journals (Sweden)

Md Arshad Mohd Khairuddin

2017-01-01

Full Text Available Acute myocardial infarction or myocardial infarction (MI is a major health problem, due to diminished flow of blood to the heart, leads to higher rates of mortality and morbidity. The most specific markers for cardiac injury are cardiac troponin I (cTnI and cardiac troponin T (cTnT which have been considered as ‘gold standard’. Due to higher specificity, determination of the level of cardiac troponins became a predominant indicator for MI. Currently, field-effect transistor (FET-based biosensors have been main interest to be implemented in portable sensors with the ultimate application in point-of-care testing (POCT. In this paper, we review on the FET-based biosensor based on its principle of operation, integration with nanomaterial, surface functionalization as well as immobilization, and the introduction of additional gate (for ambipolar conduction on the device architecture for the detection of cardiac troponin I (cTnI biomarker.

Cardiac expression of microsomal triglyceride transfer protein is increased in obesity and serves to attenuate cardiac triglyceride accumulation

DEFF Research Database (Denmark)

Bartels, Emil D; Nielsen, Jan M; Hellgren, Lars I

2009-01-01

Obesity causes lipid accumulation in the heart and may lead to lipotoxic heart disease. Traditionally, the size of the cardiac triglyceride pool is thought to reflect the balance between uptake and beta-oxidation of fatty acids. However, triglycerides can also be exported from cardiomyocytes via...... secretion of apolipoproteinB-containing (apoB) lipoproteins. Lipoprotein formation depends on expression of microsomal triglyceride transfer protein (MTP); the mouse expresses two isoforms of MTP, A and B. Since many aspects of the link between obesity-induced cardiac disease and cardiac lipid metabolism...... remain unknown, we investigated how cardiac lipoprotein synthesis affects cardiac expression of triglyceride metabolism-controlling genes, insulin sensitivity, and function in obese mice. Heart-specific ablation of MTP-A in mice using Cre-loxP technology impaired upregulation of MTP expression...

A case of multiple cardiac calcified amorphous tumours

Directory of Open Access Journals (Sweden)

Amrit Chowdhary

2017-05-01

Full Text Available Cardiac calcified amorphous tumours of the heart are rare non-neoplastic cardiac masses that can present like a malignant mass or an intra-cardiac thrombus. We report an extremely unusual case of a 73 year old man who presented to hospital with dyspnoea and subsequent investigations revealed multiple cardiac CATs.

Cardiac pacing systems and implantable cardiac defibrillators (ICDs): a radiological perspective of equipment, anatomy and complications

Energy Technology Data Exchange (ETDEWEB)

Burney, K. E-mail: apqz59@dsl.pipex.comk1511@hotmail.com; Burchard, F.; Papouchado, M.; Wilde, P

2004-08-01

Cardiac pacing is a proven and effective treatment in the management of many cardiac arrhythmias. Implantable cardiac defibrillators (ICDs) are beneficial for certain patient groups with a history of serious, recurrent ventricular dysrhythmias, with a high risk of sudden cardiac death. Pacemaker devices take many forms and are highly visible on the chest radiograph. The radiographic appearances of ICDs and pacemakers can be similar and are subject to similar complications. The anatomical approach to the implantation, the type of device used and anatomical variations will all affect the appearance of these devices on the chest film. Pacemaker complications identified radiographically include pneumothorax, lead malpositioning, lead displacement or fracture, fracture of outer conductor coil, loose connection between the lead and pacemaker connector block, lack of redundant loops in paediatric patients and excessive manipulation of the device by the patient (Twiddler's syndrome). This pictorial review highlights the role of chest radiography in the diagnosis of post-cardiac pacing and ICD insertion complications, as well as demonstrating the normal appearances of the most frequently implanted devices.

Cardiac imaging. A multimodality approach

Energy Technology Data Exchange (ETDEWEB)

Thelen, Manfred [Johannes Gutenberg University Hospital, Mainz (Germany); Erbel, Raimund [University Hospital Essen (Germany). Dept. of Cardiology; Kreitner, Karl-Friedrich [Johannes Gutenberg University Hospital, Mainz (Germany). Clinic and Polyclinic for Diagnostic and Interventional Radiology; Barkhausen, Joerg (eds.) [University Hospital Schleswig-Holstein, Luebeck (Germany). Dept. of Radiology and Nuclear Medicine

2009-07-01

An excellent atlas on modern diagnostic imaging of the heart Written by an interdisciplinary team of experts, Cardiac Imaging: A Multimodality Approach features an in-depth introduction to all current imaging modalities for the diagnostic assessment of the heart as well as a clinical overview of cardiac diseases and main indications for cardiac imaging. With a particular emphasis on CT and MRI, the first part of the atlas also covers conventional radiography, echocardiography, angiography and nuclear medicine imaging. Leading specialists demonstrate the latest advances in the field, and compare the strengths and weaknesses of each modality. The book's second part features clinical chapters on heart defects, endocarditis, coronary heart disease, cardiomyopathies, myocarditis, cardiac tumors, pericardial diseases, pulmonary vascular diseases, and diseases of the thoracic aorta. The authors address anatomy, pathophysiology, and clinical features, and evaluate the various diagnostic options. Key features: - Highly regarded experts in cardiology and radiology off er image-based teaching of the latest techniques - Readers learn how to decide which modality to use for which indication - Visually highlighted tables and essential points allow for easy navigation through the text - More than 600 outstanding images show up-to-date technology and current imaging protocols Cardiac Imaging: A Multimodality Approach is a must-have desk reference for cardiologists and radiologists in practice, as well as a study guide for residents in both fields. It will also appeal to cardiac surgeons, general practitioners, and medical physicists with a special interest in imaging of the heart. (orig.)

Cardiac stress test as a risk-stratification tool for posttransplant cardiac outcomes in diabetic kidney transplant recipients.

Science.gov (United States)

Singh, Neeraj; Parikh, Samir; Bhatt, Udayan; Vonvisger, Jon; Nori, Uday; Hasan, Ayesha; Samavedi, Srinivas; Andreoni, Kenneth; Henry, Mitchell; Pelletier, Ronald; Rajab, Amer; Elkhammas, Elmahdi; Pesavento, Todd

2012-12-27

The utility of cardiac stress testing as a risk-stratification tool before kidney transplantation remains debatable owing to discordance with coronary angiography and outcome yields at different centers. We conducted a retrospective study of 273 diabetic kidney transplant recipients from 2006 to 2010. By protocol, all diabetic patients underwent pharmacological radionucleotide stress test or dobutamine stress echocardiography before transplant. We compared the 1-year cardiac outcomes between those with negative stress test results and those with positive stress test results. Patients with a positive stress test result (n=67) underwent coronary angiogram, and significant coronary artery disease (≥70% coronary stenosis) was found in 35 (52.2%) patients. Of the latter, 32 (91.4%) underwent cardiac revascularization (24 underwent cardiac stenting and 8 underwent coronary artery bypass grafting). The rest (n=35) were treated medically. Within 1 year after transplant, the group with positive stress test results experienced more cardiac events (34.3% vs. 3.9%, P<0.001) including acute myocardial infarction (22.4% vs. 3.4%, P<0.001) and ventricular arrhythmias (8.9% vs. 0.05%, P=0.001), higher all-cause mortality (19.4% vs. 4.8%, P<0.001), and cardiac mortality (17.9% vs. 0.9%, P<0.001) compared with the group with negative stress test results. In this diabetic population, stress testing showed positive and negative predictive values of 34.3% and 96.1%, respectively. Pharmacological cardiac stress testing provided excellent risk stratification in diabetic kidney transplant recipients.

Pathological links between stroke and cardiac arrest

Institute of Scientific and Technical Information of China (English)

Shaila Ghanekar; Sydney Corey; Trenton Lippert; Cesar V.Borlongan

2017-01-01

There may be a pathological connection between cardiac failure and ischemic stroke.In this article we describe pertinent research that demonstrates subsequent death of cardiac and neural myocytes in the post ischemic stroke brain.Current stroke therapy overlooks the connection between cardiac and cerebrovascular events and fails to address the shared risk factors.Current pre-clinical stroke investigations have provided evidence that suggests the presence of an indirect cell death pathway in which toxic molecules emanate from the stroke brain and trigger cardiac cell death.On the other hand,other studies highlight the presence of a reverse cell death cascade in which toxic molecules from the heart,following cardiac arrest,travel to the brain and induce ischemic cell death.Further examination of these putative cell death pathways between ischemic stroke and cardiac arrest will prompt the advancement of innovative treatments specifically targeting both diseases,leading to ameliorated clinical results of patients diagnosed with heart failure and ischemic stroke.

The definition of exertion-related cardiac events.

Science.gov (United States)

Rai, M; Thompson, P D

2011-02-01

Vigorous physical activity increases the risk of sudden cardiac death (SCD) and acute myocardial infarction (AMI) but there is no standard definition as to what constitutes an exertion-related cardiac event, specifically the time interval between physical exertion and cardiac event. A systematic review of studies related to exertion-related cardiac events was performed and the time interval between exertion and the event or the symptoms leading to the event was looked for in all the articles selected for inclusion. A total of 12 of 26 articles "suggested" or "defined" exertion-related events as those events whose symptoms started during or within 1 h of exertion. Others used definitions of 0.5 h, 2 h, "during exertion", "during or immediately post exertion" and "during or within several hours after exertion". It is suggested, therefore, that the definition of an exertion-related cardiac event be established as a cardiac event in which symptoms started during or within 1 h of physical exertion.

Awareness in cardiac anesthesia.

LENUS (Irish Health Repository)

Serfontein, Leon

2010-02-01

Cardiac surgery represents a sub-group of patients at significantly increased risk of intraoperative awareness. Relatively few recent publications have targeted the topic of awareness in this group. The aim of this review is to identify areas of awareness research that may equally be extrapolated to cardiac anesthesia in the attempt to increase understanding of the nature and significance of this scenario and how to reduce it.

Radiation exposure during cardiac catheterization procedures

International Nuclear Information System (INIS)

Kicken, P.J.H.; Huyskens, C.J.; Michels, H.R.

1988-01-01

For some time there has been an increased interest in more information about radiation exposure during cardiac catheterization because of: relatively high doses to workers and patient; rapid increase of numbers of examinations; introduction of new procedure-types (e.g. Percutaneous Transluminal Coronary Angiography, PTCA) and introduction of new techniques (e.g. Digital Subtraction Angiography, DSA). This paper reports about a study on the exposure to medical personnel and patient in two major hospitals in the Netherlands. The Total number of cardiac catheterization procedures in both hospitals amounts to circa 3000 per year (approximately 10% of all cardiac procedures c.q. 20% of all PTCA procedures in the Netherlands). This study is related to 1300 cardiac examinations

Incidental Cardiac Findings on Thoracic Imaging.

LENUS (Irish Health Repository)

Kok, Hong Kuan

2013-02-07

The cardiac structures are well seen on nongated thoracic computed tomography studies in the investigation and follow-up of cardiopulmonary disease. A wide variety of findings can be incidentally picked up on careful evaluation of the pericardium, cardiac chambers, valves, and great vessels. Some of these findings may represent benign variants, whereas others may have more profound clinical importance. Furthermore, the expansion of interventional and surgical practice has led to the development and placement of new cardiac stents, implantable pacemaker devices, and prosthetic valves with which the practicing radiologist should be familiar. We present a collection of common incidental cardiac findings that can be readily identified on thoracic computed tomography studies and briefly discuss their clinical relevance.

An update on insertable cardiac monitors

DEFF Research Database (Denmark)

Olsen, Flemming J; Biering-Sørensen, Tor; Krieger, Derk W

2015-01-01

Continuous cardiac rhythm monitoring has undergone compelling progress over the past decades. Cardiac monitoring has emerged from 12-lead electrocardiograms being performed at the discretion of the treating physician to in-hospital telemetry, Holter monitoring, prolonged external event monitoring...... turning point in the field of arrhythmia management. However, their role in the detection of paroxysmal atrial fibrillation after cryptogenic strokes has yet to evolve. This will be the main focus of this review. Issues surrounding patient selection, clinical relevance and determination of cost......-effectiveness for prolonged cardiac monitoring require further studies. Furthermore, insertable cardiac monitoring has not only the potential to augment diagnostic capabilities but also to improve the management of paroxysmal atrial fibrillation....

Cardiac output measurement

Directory of Open Access Journals (Sweden)

Andreja Möller Petrun

2014-02-01

Full Text Available In recent years, developments in the measuring of cardiac output and other haemodynamic variables are focused on the so-called minimally invasive methods. The aim of these methods is to simplify the management of high-risk and haemodynamically unstable patients. Due to the need of invasive approach and the possibility of serious complications the use of pulmonary artery catheter has decreased. This article describes the methods for measuring cardiac output, which are based on volume measurement (Fick method, indicator dilution method, pulse wave analysis, Doppler effect, and electrical bioimpedance.

Cardiac arrest

Science.gov (United States)

... magnesium. These minerals help your heart's electrical system work. Abnormally high or low levels can cause cardiac arrest. Severe physical stress. Anything that causes a severe stress on your ...

42 CFR 410.49 - Cardiac rehabilitation program and intensive cardiac rehabilitation program: Conditions of coverage.

Science.gov (United States)

2010-10-01

... of the items and services furnished under the plan. (iii) The goals set for the individual under the... prescribed exercise, cardiac risk factor modification, psychosocial assessment, and outcomes assessment... section. Intensive cardiac rehabilitation site means a hospital outpatient setting or physician's office...

Nppa and Nppb act redundantly during zebrafish cardiac development to confine AVC marker expression and reduce cardiac jelly volume.

Science.gov (United States)

Grassini, Daniela R; Lagendijk, Anne K; De Angelis, Jessica E; Da Silva, Jason; Jeanes, Angela; Zettler, Nicole; Bower, Neil I; Hogan, Benjamin M; Smith, Kelly A

2018-05-11

Atrial natriuretic peptide ( nppa/anf ) and brain natriuretic peptide ( nppb/bnp ) form a gene cluster with expression in the chambers of the developing heart. Despite restricted expression, a function in cardiac development has not been demonstrated by mutant analysis. This is attributed to functional redundancy however their genomic location in cis has impeded formal analysis. Using genome-editing, we generated mutants for nppa and nppb and found single mutants indistinguishable from wildtype whereas nppa / nppb double mutants display heart morphogenesis defects and pericardial oedema. Analysis of atrioventricular canal (AVC) markers show expansion of bmp4 , tbx2b, has2 and versican expression into the atrium of double mutants. This expanded expression correlates with increased extracellular matrix in the atrium. Using a biosensor for Hyaluronic acid to measure the cardiac jelly (cardiac extracellular matrix), we confirm cardiac jelly expansion in nppa / nppb double mutants. Finally, bmp4 knockdown rescues the expansion of has2 expression and cardiac jelly in double mutants. This definitively shows that nppa and nppb function redundantly during cardiac development to restrict gene expression to the AVC, preventing excessive cardiac jelly synthesis in the atrial chamber. © 2018. Published by The Company of Biologists Ltd.

Preoperative cardiac computed tomography for demonstration of congenital cardiac septal defect in adults

Energy Technology Data Exchange (ETDEWEB)

Eom, Hye-Joung; Yang, Dong Hyun; Kang, Joon-Won; Lim, Tae-Hwan [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of); Kim, Dae-Hee; Song, Jong-Min; Kang, Duk-Hyun; Song, Jae-Kwan [University of Ulsan College of Medicine, Department of Cardiology and Heart Institute, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of); Kim, Joon Bum; Jung, Sung-Ho; Choo, Suk Jung; Chung, Cheol Hyun; Lee, Jae Won [University of Ulsan College of Medicine, Department of Cardiothoracic surgery, Cardiac Imaging Center, Asan Medical Center, Seoul (Korea, Republic of)

2015-06-01

We aimed to evaluate the role of preoperative cardiac computed tomography (CT) for adults with congenital cardiac septal defect (CSD). Sixty-five consecutive patients who underwent preoperative CT and surgery for CSD were included. The diagnostic accuracy of CT and the concordance rate of the subtype classification of CSD were evaluated using surgical findings as the reference standard. Sixty-five patients without CSD who underwent cardiac valve surgery were used as a control group. An incremental value of CT over echocardiography was described retrospectively. Sensitivity and specificity of CT for diagnosis of CSD were 95 % and 100 %, respectively. The concordance rate of subtype classification was 91 % in CT and 92 % in echocardiography. The maximum size of the defect measured by CT correlated well with surgical measurement (r = 0.82), and the limit of agreement was -0.9 ± 7.42 mm. In comparison with echocardiography, CT was able to detect combined abnormalities in three cases, and exclusively provided correct subtype classification or clarified suspected abnormal findings found on echocardiography in seven cases. Cardiac CT can accurately demonstrates CSD in preoperative adult patients. CT may have an incremental role in preoperative planning, particularly in those with more complex anatomy. (orig.)

Differentiation of C2C12 myoblasts expressing lamin A mutated at a site responsible for Emery-Dreifuss muscular dystrophy is improved by inhibition of the MEK-ERK pathway and stimulation of the PI3-kinase pathway

International Nuclear Information System (INIS)

Favreau, Catherine; Delbarre, Erwan; Courvalin, Jean-Claude; Buendia, Brigitte

2008-01-01

Mutation R453W in A-type lamins, that are major nuclear envelope proteins, generates Emery-Dreifuss muscular dystrophy. We previously showed that mouse myoblasts expressing R453W-lamin A incompletely exit the cell cycle and differentiate into myocytes with a low level of multinucleation. Here we attempted to improve differentiation by treating these cells with a mixture of PD98059, an extracellular-regulated kinase (ERK) kinase (also known as mitogen-activated kinase, MEK) inhibitor, and insulin-like growth factor-II, an activator of phosphoinositide 3-kinase. We show that mouse myoblasts expressing R453W-lamin A were sensitive to the drug treatment as shown by (i) an increase in multinucleation, (ii) downregulation of proliferation markers (cyclin D1, hyperphosphorylated Rb), (iii) upregulation of myogenin, and (iv) sustained activation of p21 and cyclin D3. However, nuclear matrix anchorage of p21 and cyclin D3 in a complex with hypophosphorylated Rb that is critical to trigger cell cycle arrest and myogenin induction was deficient and incompletely restored by drug treatment. As the turn-over of R453W-lamin A at the nuclear envelope was greatly enhanced, we propose that R453W-lamin A impairs the capacity of the nuclear lamina to serve as scaffold for substrates of the MEK-ERK pathway and for MyoD-induced proteins that play a role in the differentiation process

Pediatric cardiac postoperative care

Directory of Open Access Journals (Sweden)

Auler Jr. José Otávio Costa

2002-01-01

Full Text Available The Heart Institute of the University of São Paulo, Medical School is a referral center for the treatment of congenital heart diseases of neonates and infants. In the recent years, the excellent surgical results obtained in our institution may be in part due to modern anesthetic care and to postoperative care based on well-structured protocols. The purpose of this article is to review unique aspects of neonate cardiovascular physiology, the impact of extracorporeal circulation on postoperative evolution, and the prescription for pharmacological support of acute cardiac dysfunction based on our cardiac unit protocols. The main causes of low cardiac output after surgical correction of heart congenital disease are reviewed, and methods of treatment and support are proposed as derived from the relevant literature and our protocols.

CARFMAP: A Curated Pathway Map of Cardiac Fibroblasts.

Directory of Open Access Journals (Sweden)

Hieu T Nim

Full Text Available The adult mammalian heart contains multiple cell types that work in unison under tightly regulated conditions to maintain homeostasis. Cardiac fibroblasts are a significant and unique population of non-muscle cells in the heart that have recently gained substantial interest in the cardiac biology community. To better understand this renaissance cell, it is essential to systematically survey what has been known in the literature about the cellular and molecular processes involved. We have built CARFMAP (http://visionet.erc.monash.edu.au/CARFMAP, an interactive cardiac fibroblast pathway map derived from the biomedical literature using a software-assisted manual data collection approach. CARFMAP is an information-rich interactive tool that enables cardiac biologists to explore the large body of literature in various creative ways. There is surprisingly little overlap between the cardiac fibroblast pathway map, a foreskin fibroblast pathway map, and a whole mouse organism signalling pathway map from the REACTOME database. Among the use cases of CARFMAP is a common task in our cardiac biology laboratory of identifying new genes that are (1 relevant to cardiac literature, and (2 differentially regulated in high-throughput assays. From the expression profiles of mouse cardiac and tail fibroblasts, we employed CARFMAP to characterise cardiac fibroblast pathways. Using CARFMAP in conjunction with transcriptomic data, we generated a stringent list of six genes that would not have been singled out using bioinformatics analyses alone. Experimental validation showed that five genes (Mmp3, Il6, Edn1, Pdgfc and Fgf10 are differentially regulated in the cardiac fibroblast. CARFMAP is a powerful tool for systems analyses of cardiac fibroblasts, facilitating systems-level cardiovascular research.

CARFMAP: A Curated Pathway Map of Cardiac Fibroblasts.

Science.gov (United States)

Nim, Hieu T; Furtado, Milena B; Costa, Mauro W; Kitano, Hiroaki; Rosenthal, Nadia A; Boyd, Sarah E

2015-01-01

The adult mammalian heart contains multiple cell types that work in unison under tightly regulated conditions to maintain homeostasis. Cardiac fibroblasts are a significant and unique population of non-muscle cells in the heart that have recently gained substantial interest in the cardiac biology community. To better understand this renaissance cell, it is essential to systematically survey what has been known in the literature about the cellular and molecular processes involved. We have built CARFMAP (http://visionet.erc.monash.edu.au/CARFMAP), an interactive cardiac fibroblast pathway map derived from the biomedical literature using a software-assisted manual data collection approach. CARFMAP is an information-rich interactive tool that enables cardiac biologists to explore the large body of literature in various creative ways. There is surprisingly little overlap between the cardiac fibroblast pathway map, a foreskin fibroblast pathway map, and a whole mouse organism signalling pathway map from the REACTOME database. Among the use cases of CARFMAP is a common task in our cardiac biology laboratory of identifying new genes that are (1) relevant to cardiac literature, and (2) differentially regulated in high-throughput assays. From the expression profiles of mouse cardiac and tail fibroblasts, we employed CARFMAP to characterise cardiac fibroblast pathways. Using CARFMAP in conjunction with transcriptomic data, we generated a stringent list of six genes that would not have been singled out using bioinformatics analyses alone. Experimental validation showed that five genes (Mmp3, Il6, Edn1, Pdgfc and Fgf10) are differentially regulated in the cardiac fibroblast. CARFMAP is a powerful tool for systems analyses of cardiac fibroblasts, facilitating systems-level cardiovascular research.

Health Instruction Packages: Cardiac Anatomy.

Science.gov (United States)

Phillips, Gwen; And Others

Text, illustrations, and exercises are utilized in these five learning modules to instruct nurses, students, and other health care professionals in cardiac anatomy and functions and in fundamental electrocardiographic techniques. The first module, "Cardiac Anatomy and Physiology: A Review" by Gwen Phillips, teaches the learner to draw…

Lentiginosis, Deafness and Cardiac Abnormalities*

African Journals Online (AJOL)

1973-01-06

Jan 6, 1973 ... His height. mass. intelligence and genitalia were normal. The aSSOCiatIOn between deafness and disturbance of cardiac conduction and between pigmented skin lesions and cardiac abnormalities, has been well described. Should. ~I patient present with multiple lentigines and/or familial sensineural ...

Automatic referral to cardiac rehabilitation.

Science.gov (United States)

Fischer, Jane P

2008-01-01

The pervasive negative impact of cardiovascular disease in the United States is well documented. Although advances have been made, the campaign to reduce the occurrence, progression, and mortality continues. Determining evidence-based data is only half the battle. Implementing new and updated clinical guidelines into daily practice is a challenging task. Cardiac rehabilitation is an example of a proven intervention whose benefit is hindered through erratic implementation. The American Association of Cardiovascular and Pulmonary Rehabilitation (AACVPR), the American College of Cardiology (ACC), and the American Heart Association (AHA) have responded to this problem by publishing the AACVPR/ACC/AHA 2007 Performance Measures on Cardiac Rehabilitation for Referral to and Delivery of Cardiac Rehabilitation/Secondary Prevention Services. This new national guideline recommends automatic referral to cardiac rehabilitation for every eligible patient (performance measure A-1). This article offers guidance for the initiation of an automatic referral system, including individualizing your protocol with regard to electronic or paper-based order entry structures.

Effect of IR Laser on Myoblasts: Prospects of Application for Counteracting Microgravity-Induced Muscle Atrophy

Science.gov (United States)

Monici, Monica; Cialdai, Francesca; Romano, Giovanni; Corsetto, Paola Antonia; Rizzo, Angela Maria; Caselli, Anna; Ranaldi, Francesco

2013-02-01

Microgravity-induced muscle atrophy is a problem of utmost importance for the impact it may have on the health and performance of astronauts. Therefore, appropriate countermeasures are needed to prevent disuse atrophy and favour muscle recovery. Muscle atrophy is characterized by loss of muscle mass and strength, and a shift in substrate utilization from fat to glucose, that leads to a reduced metabolic efficiency and enhanced fatigability. Laser therapy is already used in physical medicine and rehabilitation to accelerate muscle recovery and in sports medicine to prevent damages produced by metabolic disturbances and inflammatory reactions after heavy exercise. The aim of the research we present was to get insights on possible benefits deriving from the application of an advanced infrared laser system to counteract deficits of muscle energy metabolism and stimulate the recovery of the hypotrophic tissue. The source used was a Multiwave Locked System (MLS) laser, which combines continuous and pulsed emissions at 808 nm and 905 nm, respectively. We studied the effect of MLS treatment on morphology and energy metabolism of C2C12 cells, a widely accepted myoblast model, previously exposed to microgravity conditions modelled by a Random Positioning Machine. The MLS laser treatment was able to restore basal levels of serine/threonine protein phosphatase activity and to counteract cytoskeletal alterations and increase in glycolytic enzymes activity that occurred following the exposure to modelled microgravity. In conclusion, the results provide interesting insights for the application of infrared laser in the treatment of muscle atrophy.

Association of morning blood pressure surge with carotid intima-media thickness and cardiac dysfunction in patients with cardiac syndrome-X.

Science.gov (United States)

Mahfouz, Ragab A; Goda, Mohammad; Galal, Islam; Ghareb, Mohamed S

2018-05-23

Background & hypothesis: We hypothesized that exaggerated morning blood pressure surge, may contribute in cardiac dysfunction and arterial stiffness in patients with cardiac syndrome X. Thus we investigated the impact of morning blood pressure surge on cardiac function and carotid intima-media thickness in subjects with cardiac syndrome X. We studied patients with cardiac syndrome X using ambulatory blood pressure monitoring and investigated the association of morning blood pressure surge with carotid intima thickness, left atrial volume index and left ventricular filling (E/e'). Seventy patients with cardiac syndrome X were enrolled for the study and compared with 70 age and sex matched controls. Patients with cardiac syndrome X were stratified based on the systolic morning blood pressure surge value of control subjects to patients with exaggerated blood pressure surge (n = 42) and those with normal morning blood pressure surge (n = 28). Basal heart rate (p blood pressure surge group than those with morning blood pressure surge group. Morning blood pressure surge was significantly correlated with carotid intima-media thickness, high sensitive C-reactive protein, left atrial volume index and E/e' ratio in patients with cardiac syndrome X. In multivariate analysis, exaggerated morning blood pressure surge was the only independent predictor of increased carotid intima-media thickness (OR = 2.379; p blood pressure surge is an independent predictor for arterial stiffness and diastolic dysfunction in patients with cardiac syndrome X.

Pediatric cardiac emergencies: Children are not small adults

Directory of Open Access Journals (Sweden)

Frazier Aisha

2011-01-01

Full Text Available Compared with adults, cardiac emergencies are infrequent in children and clinical presentation is often quite variable. In adults, cardiac emergencies are most commonly related to complications of coronary artery disease; however, in pediatric cases, the coronaries are only rarely the underlying problem. Pediatric cardiac emergencies comprise a range of pathology including but not limited to undiagnosed congenital heart disease in the infant; complications of palliated congenital heart disease in children; arrhythmias related to underlying cardiac pathology in the teenager and acquired heart disease. The emergency room physician and pediatric intensivist will usually be the first and second lines of care for pediatric cardiac emergencies and thus it is imperative that they have knowledge of the diverse presentations of cardiac disease in order to increase the likelihood of delivering early appropriate therapy and referral. The objective of this review is to outline cardiac emergencies in the pediatric population and contrast the presentation with adults.

Cardiac biomarkers in Neonatology

OpenAIRE

Vijlbrief, D.C.

2015-01-01

In this thesis, the role for cardiac biomarkers in neonatology was investigated. Several clinically relevant results were reported. In term and preterm infants, hypoxia and subsequent adaptation play an important role in cardiac biomarker elevation. The elevated natriuretic peptides are indicative of abnormal function; elevated troponins are suggestive for cardiomyocyte damage. This methodology makes these biomarkers of additional value in the treatment of newborn infants, separate or as a co...

Liposome-based vascular endothelial growth factor-165 transfection with skeletal myoblast for treatment of ischaemic limb disease.

Science.gov (United States)

Ye, Lei; Haider, Husnain Kh; Esa, Wahidah Bte; Su, Liping; Law, Peter K; Zhang, Wei; Lim, Yeanteng; Poh, Kian Keong; Sim, Eugene K W

2010-01-01

The study aims to use cholesterol (Chol) + DOTAP liposome (CD liposome) based human vascular endothelial growth factor-165 (VEGF(165)) gene transfer into skeletal myoblasts (SkMs) for treatment of acute hind limb ischaemia in a rabbit model. The feasibility and efficacy of CD liposome mediated gene transfer with rabbit SkMs were characterized using plasmid carrying enhanced green fluorescent protein (pEGFP) and assessed by flow cytometry. After optimization, SkMs were transfected with CD lipoplexes carrying plasmid-VEGF(165) (CD-pVEGF(165)) and transplanted into rabbit ischaemic limb. Animals were randomized to receive intramuscular injection of Medium199 (M199; group 1), non-transfected SkM (group 2) or CD-pVEGF(165) transfected SkM (group 3). Flow cytometry revealed that up to 16% rabbit SkMs were successfully transfected with pEGFP. Based on the optimized transfection condition, transfected rabbit SkM expressed VEGF(165) up to day 18 with peak at day 2. SkMs were observed in all cell-transplanted groups, as visualized with 6-diamidino-2-phenylindole and bromodeoxyuridine. Angiographic blood vessel score revealed increased collateral vessel development in group 3 (39.7 +/- 2.0) compared with group 2 (21.6 +/- 1.1%, P limb and may serve as a safe and new therapeutic modality for the repair of acute ischaemic limb disease.

Cardiac sympathetic neuronal imaging using PET

International Nuclear Information System (INIS)

Lautamaeki, Riikka; Tipre, Dnyanesh; Bengel, Frank M.

2007-01-01

Balance of the autonomic nervous system is essential for adequate cardiac performance, and alterations seem to play a key role in the development and progression of various cardiac diseases. PET imaging of the cardiac autonomic nervous system has advanced extensively in recent years, and multiple pre- and postsynaptic tracers have been introduced. The high spatial and temporal resolution of PET enables noninvasive quantification of neurophysiologic processes at the tissue level. Ligands for catecholamine receptors, along with radiolabeled catecholamines and catecholamine analogs, have been applied to determine involvement of sympathetic dysinnervation at different stages of heart diseases such as ischemia, heart failure, and arrhythmia. This review summarizes the recent findings in neurocardiological PET imaging. Experimental studies with several radioligands and clinical findings in cardiac dysautonomias are discussed. (orig.)

Intrinsic cardiac nervous system in tachycardia induced heart failure.

Science.gov (United States)

Arora, Rakesh C; Cardinal, Rene; Smith, Frank M; Ardell, Jeffrey L; Dell'Italia, Louis J; Armour, J Andrew

2003-11-01

The purpose of this study was to test the hypothesis that early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiac function. After 2 wk of rapid ventricular pacing in nine anesthetized canines, cardiac and right atrial neuronal function were evaluated in situ in response to enhanced cardiac sensory inputs, stimulation of extracardiac autonomic efferent neuronal inputs, and close coronary arterial administration of neurochemicals that included nicotine. Right atrial neuronal intracellular electrophysiological properties were then evaluated in vitro in response to synaptic activation and nicotine. Intrinsic cardiac nicotine-sensitive, neuronally induced cardiac responses were also evaluated in eight sham-operated, unpaced animals. Two weeks of rapid ventricular pacing reduced the cardiac index by 54%. Intrinsic cardiac neurons of paced hearts maintained their cardiac mechano- and chemosensory transduction properties in vivo. They also responded normally to sympathetic and parasympathetic preganglionic efferent neuronal inputs, as well as to locally administered alpha-or beta-adrenergic agonists or angiotensin II. The dose of nicotine needed to modify intrinsic cardiac neurons was 50 times greater in failure compared with normal preparations. That dose failed to alter monitored cardiovascular indexes in failing preparations. Phasic and accommodating neurons identified in vitro displayed altered intracellular membrane properties compared with control, including decreased membrane resistance, indicative of reduced excitability. Early-stage heart failure differentially affects the intrinsic cardiac nervous system's capacity to regulate cardiodynamics. While maintaining its capacity to transduce cardiac mechano- and chemosensory inputs, as well as inputs from extracardiac autonomic efferent neurons, intrinsic cardiac nicotine-sensitive, local-circuit neurons differentially remodel such that their capacity to

[Cardiac sarcoidosis: Diagnosis and therapeutic challenges].

Science.gov (United States)

Cohen Aubart, F; Nunes, H; Mathian, A; Haroche, J; Hié, M; Le-Thi Huong Boutin, D; Cluzel, P; Soussan, M; Waintraub, X; Fouret, P; Valeyre, D; Amoura, Z

2017-01-01

Sarcoidosis is a granulomatous disorder of unknown cause characterized by non-caseating granuloma in young adults. Cardiac involvement is rare and range from 2 to 75% depending on diagnostic criteria. Cardiac involvement in sarcoidosis may be asymptomatic or may manifest as rhythm/conduction troubles or congestive heart failure. The diagnosis and treatment of cardiac sarcoidosis may be challenging. However, advances have come in recent years from the use of cardiac MRI and 18 FDG-TEP scanner, as well as from the stratification of the risk of ventricular tachycardia/fibrillation. Due to the rarity of the disease, there is no reliable prospective large study to guide therapeutic strategy for cardiac sarcoidosis. Corticosteroids are probably efficacious, in particular in case of atrio-ventricular block or moderate heart failure. Immunosuppressive drugs have not been largely studied but methotrexate could be helpful. In refractory forms, TNF-α antagonists have been used with success. Copyright © 2016 Société Nationale Française de Médecine Interne (SNFMI). Published by Elsevier SAS. All rights reserved.

Robotic cardiac surgery: an anaesthetic challenge.

Science.gov (United States)

Wang, Gang; Gao, Changqing

2014-08-01

Robotic cardiac surgery with the da Vinci robotic surgical system offers the benefits of a minimally invasive procedure, including a smaller incision and scar, reduced risk of infection, less pain and trauma, less bleeding and blood transfusion requirements, shorter hospital stay and decreased recovery time. Robotic cardiac surgery includes extracardiac and intracardiac procedures. Extracardiac procedures are often performed on a beating heart. Intracardiac procedures require the aid of peripheral cardiopulmonary bypass via a minithoracotomy. Robotic cardiac surgery, however, poses challenges to the anaesthetist, as the obligatory one-lung ventilation (OLV) and CO2 insufflation may reduce cardiac output and increase pulmonary vascular resistance, potentially resulting in hypoxaemia and haemodynamic compromise. In addition, surgery requires appropriate positioning of specialised cannulae such as an endopulmonary vent, endocoronary sinus catheter, and endoaortic clamp catheter under the guidance of transoesophageal echocardiography. Therefore, cardiac anaesthetists should have a working knowledge of these systems, OLV and haemodynamic support. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Epworth HealthCare cardiac surgery audit report 2011.

Science.gov (United States)

Chorley, T; Baker, L

2012-10-01

2011 is the first year Epworth has contributed to Australian and New Zealand Society of Cardiac and Thoracic Surgeons cardiac surgery database. There is now a 30-day follow-up data for all cardiac surgical patients as well as benchmarking of our results with 19 public hospitals and 6 private hospitals contributing data to the Australian and New Zealand Society of Cardiac and Thoracic Surgeons. This is an extension of the John Fuller Melbourne University database that has compiled cardiac surgery data for the last 30 years. © 2012 The Authors; Internal Medicine Journal © 2012 Royal Australasian College of Physicians.

The potential of cardiac allografts from donors after cardiac death at the University of Wisconsin Organ Procurement Organization.

Science.gov (United States)

Osaki, Satoru; Anderson, James E; Johnson, Maryl R; Edwards, Niloo M; Kohmoto, Takushi

2010-01-01

The purpose of this study is to investigate the potential availability of hearts from adult donation after cardiac death (DCD) donors within an acceptable hypoxic period. We retrospectively reviewed a donor database from the University of Wisconsin Organ Procurement Organization Donor Tracking System between 2004 and 2006. The DCD population (n=78) was screened using our inclusion criteria for DCD cardiac donor suitability, including warm ischaemic time (WIT) limit of 30 min. In the same period, 70 hearts were donated from brain-dead donors. Of 78 DCD donors, 12 (15%) met our proposed DCD cardiac donor criteria. The mean WIT of these 12 DCD donors was 21 min (range 14-29 min). When inclusion criteria are further narrowed to (1) age Based on our proposed DCD cardiac donor criteria, the potential application of DCD cardiac donors would represent an increase in cardiac donation of 17% (12/70) during the 3-year period. When the criteria were narrowed to the initial 'ideal' case, only two donors met such criteria, suggesting that such 'ideal' DCD donors are rare but they do exist. Copyright 2009 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Cardiac Ochronosis

Science.gov (United States)

Erek, Ersin; Casselman, Filip P.A.; Vanermen, Hugo

2004-01-01

We report the case of 67-year-old woman who underwent aortic valve replacement and mitral valve repair due to ochronotic valvular disease (alkaptonuria), which was diagnosed incidentally during cardiac surgery. PMID:15745303

STEM promotion through museum exhibits on cardiac monitoring & cardiac rhythm management.

Science.gov (United States)

Countryman, Jordan D; Dow, Douglas E

2014-01-01

Formal education in science, technology, engineering and math (STEM) does not successfully engage all of the students who have potential to become skilled in STEM activities and careers. Museum exhibits may be able to reach and engage a broader range of the public. STEM Exhibits that are both understandable and capture the imagination of viewers may contribute toward increased interest in STEM activities. One such topic for such an exhibit could be cardiac pacemakers and cardioverter defibrillators that sustain life. Although museums have existed for centuries, the available types of exhibit designs has dramatically increased in recent decades due to innovations in technology. Science and technology museums have especially taken advantage of the progression of exhibit design to developed new ways to communicate to their viewers. These novel presentation tools allow museums to more effectively convey to and engage viewers. This paper examines the techniques employed by museums in exhibits and considers the practices of several museums with exhibits related to cardiac monitoring (CM) and cardiac rhythm management (CRM).

Cardiac imaging in adults

International Nuclear Information System (INIS)

Jaffe, C.C.

1987-01-01

This book approaches adult cardiac disease from the correlative imaging perspective. It includes chest X-rays and angiographs, 2-dimensional echocardiograms with explanatory diagrams for clarity, plus details on digital radiology, nuclear medicine techniques, CT and MRI. It also covers the normal heart, valvular heart disease, myocardial disease, pericardial disease, bacterial endocarditis, aortic aneurysm, cardiac tumors, and congenital heart disease of the adult. It points out those aspects where one imaging technique has significant superiority

Cardiac imaging in adults

Energy Technology Data Exchange (ETDEWEB)

Jaffe, C.C.

1987-01-01

This book approaches adult cardiac disease from the correlative imaging perspective. It includes chest X-rays and angiographs, 2-dimensional echocardiograms with explanatory diagrams for clarity, plus details on digital radiology, nuclear medicine techniques, CT and MRI. It also covers the normal heart, valvular heart disease, myocardial disease, pericardial disease, bacterial endocarditis, aortic aneurysm, cardiac tumors, and congenital heart disease of the adult. It points out those aspects where one imaging technique has significant superiority.

C.A.U.S.E.: Cardiac arrest ultra-sound exam--a better approach to managing patients in primary non-arrhythmogenic cardiac arrest.

Science.gov (United States)

Hernandez, Caleb; Shuler, Klaus; Hannan, Hashibul; Sonyika, Chionesu; Likourezos, Antonios; Marshall, John

2008-02-01

Cardiac arrest is a condition frequently encountered by physicians in the hospital setting including the Emergency Department, Intensive Care Unit and medical/surgical wards. This paper reviews the current literature involving the use of ultrasound in resuscitation and proposes an algorithmic approach for the use of ultrasound during cardiac arrest. At present there is the need for a means of differentiating between various causes of cardiac arrest, which are not a direct result of a primary ventricular arrhythmia. Identifying the cause of pulseless electrical activity or asystole is important as the underlying cause is what guides management in such cases. This approach, incorporating ultrasound to manage cardiac arrest aids in the diagnosis of the most common and easily reversible causes of cardiac arrest not caused by primary ventricular arrhythmia, namely; severe hypovolemia, tension pneumothorax, cardiac tamponade, and massive pulmonary embolus. These four conditions are addressed in this paper using four accepted emergency ultrasound applications to be performed during resuscitation of a cardiac arrest patient with the aim of determining the underlying cause of a cardiac arrest. Identifying the underlying cause of cardiac arrest represents the one of the greatest challenges of managing patients with asystole or PEA and accurate determination has the potential to improve management by guiding therapeutic decisions. We include several clinical images demonstrating examples of cardiac tamponade, massive pulmonary embolus, and severe hypovolemia secondary to abdominal aortic aneurysm. In conclusion, this protocol has the potential to reduce the time required to determine the etiology of a cardiac arrest and thus decrease the time between arrest and appropriate therapy.

Cardiac ankyrin repeat protein attenuates cardiac hypertrophy by inhibition of ERK1/2 and TGF-β signaling pathways.

Directory of Open Access Journals (Sweden)

Yao Song

Full Text Available AIMS: It has been reported that cardiac ankyrin repeat protein is associated with heart development and diseases. This study is aimed to investigate the role of CARP in heart hypertrophy in vivo. METHODS AND RESULTS: We generated a cardiac-specific CARP-overexpressing transgenic mouse. Although such animals did not display any overt physiological abnormality, they developed less cardiac hypertrophy in response to pressure overload than did wildtype mice, as indicated by heart weight/body weight ratios, echocardiographic and histological analyses, and expression of hypertrophic markers. These mice also exhibited less cardiac hypertrophy after infusion of isoproterenol. To gain a molecular insight into how CARP attenuated heart hypertrophy, we examined expression of the mitogen-activated protein kinase cascade and found that the concentrations of phosphorylated ERK1/2 and MEK were markedly reduced in the hearts of transgenic mice subjected to pressure overload. In addition, the expressions of TGF-β and phosphorylated Smad3 were significantly downregulated in the hearts of CARP Tg mice in response to pressure overload. Furthermore, addition of human TGF-β1 could reverse the inhibitory effect of CARP on the hypertrophic response induced by phenylephrine in cardiomyocytes. It was also evidenced that the inhibitory effect of CARP on cardiac hypertrophy was not attributed to apoptosis. CONCLUSION: CARP attenuates cardiac hypertrophy, in which the ERK and TGF-β pathways may be involved. Our findings highlight the significance of CARP as an anti-hypertrophic factor in therapy of cardiac hypertrophy.

Direct cone-beam cardiac reconstruction algorithm with cardiac banding artifact correction

International Nuclear Information System (INIS)

Taguchi, Katsuyuki; Chiang, Beshan S.; Hein, Ilmar A.

2006-01-01

Multislice helical computed tomography (CT) is a promising noninvasive technique for coronary artery imaging. Various factors can cause inconsistencies in cardiac CT data, which can result in degraded image quality. These inconsistencies may be the result of the patient physiology (e.g., heart rate variations), the nature of the data (e.g., cone-angle), or the reconstruction algorithm itself. An algorithm which provides the best temporal resolution for each slice, for example, often provides suboptimal image quality for the entire volume since the cardiac temporal resolution (TRc) changes from slice to slice. Such variations in TRc can generate strong banding artifacts in multi-planar reconstruction images or three-dimensional images. Discontinuous heart walls and coronary arteries may compromise the accuracy of the diagnosis. A β-blocker is often used to reduce and stabilize patients' heart rate but cannot eliminate the variation. In order to obtain robust and optimal image quality, a software solution that increases the temporal resolution and decreases the effect of heart rate is highly desirable. This paper proposes an ECG-correlated direct cone-beam reconstruction algorithm (TCOT-EGR) with cardiac banding artifact correction (CBC) and disconnected projections redundancy compensation technique (DIRECT). First the theory and analytical model of the cardiac temporal resolution is outlined. Next, the performance of the proposed algorithms is evaluated by using computer simulations as well as patient data. It will be shown that the proposed algorithms enhance the robustness of the image quality against inconsistencies by guaranteeing smooth transition of heart cycles used in reconstruction

Cardiac ablation

Directory of Open Access Journals (Sweden)

Kelly Ratheal

2016-01-01

Full Text Available Cardiac ablation is a procedure that uses either radiofrequency or cryothermal energy to destroy cells in the heart to terminate and/or prevent arrhythmias. The indications for cardiac catheter ablation include refractory, symptomatic arrhythmias, with more specific guidelines for atrial fibrillation in particular. The ablation procedure itself involves mapping the arrhythmia and destruction of the aberrant pathway in an effort to permanently prevent the arrhythmia. There are many types of arrhythmias, and they require individualized approaches to ablation based on their innately different electrical pathways. Ablation of arrhythmias, such as Wolff-Parkinson-White syndrome, AV nodal reentrant tachycardia, and atrial-fibrillation, is discussed in this review. Ablation has a high success rate overall and minimal complication rates, leading to improved quality of life in many patients.

Cardiac transplantation: 15 years experience Cardiology Institute of Child

International Nuclear Information System (INIS)

Ceruti, B; Chiesa, P.; Tambasco, J.; Anzibar, R.; Gutierrez, C.; Barboza, S.; Manfredi, A.; Leone, R.

2012-01-01

The cardiac transplant is the treatment of choice for the cardiac insufficiency when there is not another therapeutic alternative that prolongs the life expectancy. On December 1996 The Cardiology Institute of child begin the program of Cardiac Insufficiency and Transplants of the Institute of Pediatric Cardiology, achieving the first cardiac transplant in a 14-year-old child in Uruguay. Three years later they put in practice the program of cardiac transplant in adults

[Hydatidosis simulating a cardiac tumour with pulmonary metastases].

Science.gov (United States)

Martín-Izquierdo, Marta; Martín-Trenor, Alejandro

2016-01-01

The presence of multiple symptomatic pulmonary nodules and one cardiac tumour in a child requires urgent diagnosis and treatment. Until a few decades ago, the diagnosis of a cardiac tumour was difficult and was based on a high index of suspicion from indirect signs, and required angiocardiography for confirmation. Echocardiography and other imaging techniques have also helped in the detection of cardiac neoplasms. However, it is not always easy to make the correct diagnosis. The case is presented of a 12 year-old boy with pulmonary symptoms, and diagnosed with a cardiac tumour with lung metastases. The presence of numerous pulmonary nodules was confirmed in our hospital. The echocardiogram detected a solid cardiac nodule in the right ventricle. Magnetic resonance imaging confirmed the findings and the diagnosis. Puncture-aspiration of a lung nodule gave the diagnosis of hydatidosis. He underwent open-heart surgery with cardiac cyst resection and treated with anthelmintics. The lung cysts were then excised, and he recovered uneventfully. This child had multiple pulmonary nodules and a solid cardiac nodule, and was suspected of having a cardiac tumour with pulmonary metastases. However, given the clinical history, background and morphology of pulmonary nodules, another possible aetiology for consideration is echinococcosis. The clinical picture of cardiac hydatidosis and its complications is highly variable. The clinical history is essential in these cases, as well as having a high index of suspicion. Hydatidosis should be included in the differential diagnosis of a solid, echogenic, cardiac nodule. The treatment for cardiopulmonary hydatid cysts is surgical, followed by anthelmintics. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

Cardiac CT for planning redo cardiac surgery: effect of knowledge-based iterative model reconstruction on image quality

International Nuclear Information System (INIS)

Oda, Seitaro; Weissman, Gaby; Weigold, W. Guy; Vembar, Mani

2015-01-01

The purpose of this study was to investigate the effects of knowledge-based iterative model reconstruction (IMR) on image quality in cardiac CT performed for the planning of redo cardiac surgery by comparing IMR images with images reconstructed with filtered back-projection (FBP) and hybrid iterative reconstruction (HIR). We studied 31 patients (23 men, 8 women; mean age 65.1 ± 16.5 years) referred for redo cardiac surgery who underwent cardiac CT. Paired image sets were created using three types of reconstruction: FBP, HIR, and IMR. Quantitative parameters including CT attenuation, image noise, and contrast-to-noise ratio (CNR) of each cardiovascular structure were calculated. The visual image quality - graininess, streak artefact, margin sharpness of each cardiovascular structure, and overall image quality - was scored on a five-point scale. The mean image noise of FBP, HIR, and IMR images was 58.3 ± 26.7, 36.0 ± 12.5, and 14.2 ± 5.5 HU, respectively; there were significant differences in all comparison combinations among the three methods. The CNR of IMR images was better than that of FBP and HIR images in all evaluated structures. The visual scores were significantly higher for IMR than for the other images in all evaluated parameters. IMR can provide significantly improved qualitative and quantitative image quality at in cardiac CT for planning of reoperative cardiac surgery. (orig.)

Bone morphogenetic protein-2 functions as a negative regulator in the differentiation of myoblasts, but not as an inducer for the formations of cartilage and bone in mouse embryonic tongue

Directory of Open Access Journals (Sweden)

Suzuki Erika

2011-07-01

Full Text Available Abstract Background In vitro studies using the myogenic cell line C2C12 demonstrate that bone morphogenetic protein-2 (BMP-2 converts the developmental pathway of C2C12 from a myogenic cell lineage to an osteoblastic cell lineage. Further, in vivo studies using null mutation mice demonstrate that BMPs inhibit the specification of the developmental fate of myogenic progenitor cells. However, the roles of BMPs in the phases of differentiation and maturation in skeletal muscles have yet to be determined. The present study attempts to define the function of BMP-2 in the final stage of differentiation of mouse tongue myoblast. Results Recombinant BMP-2 inhibited the expressions of markers for the differentiation of skeletal muscle cells, such as myogenin, muscle creatine kinase (MCK, and fast myosin heavy chain (fMyHC, whereas BMP-2 siRNA stimulated such markers. Neither the recombinant BMP-2 nor BMP-2 siRNA altered the expressions of markers for the formation of cartilage and bone, such as osteocalcin, alkaline phosphatase (ALP, collagen II, and collagen X. Further, no formation of cartilage and bone was observed in the recombinant BMP-2-treated tongues based on Alizarin red and Alcian blue stainings. Neither recombinant BMP-2 nor BMP-2 siRNA affected the expression of inhibitor of DNA binding/differentiation 1 (Id1. The ratios of chondrogenic and osteogenic markers relative to glyceraldehyde-3-phosphate dehydrogenase (GAPDH, a house keeping gene were approximately 1000-fold lower than those of myogenic markers in the cultured tongue. Conclusions BMP-2 functions as a negative regulator for the final differentiation of tongue myoblasts, but not as an inducer for the formation of cartilage and bone in cultured tongue, probably because the genes related to myogenesis are in an activation mode, while the genes related to chondrogenesis and osteogenesis are in a silencing mode.

Inpatient cardiac rehabilitation programs' exercise therapy for patients undergoing cardiac surgery: National Korean Questionnaire Survey.

Science.gov (United States)

Seo, Yong Gon; Jang, Mi Ja; Park, Won Hah; Hong, Kyung Pyo; Sung, Jidong

2017-02-01

Inpatient cardiac rehabilitation (ICR) has been commonly conducted after cardiac surgery in many countries, and has been reported a lots of results. However, until now, there is inadequacy of data on the status of ICR in Korea. This study described the current status of exercise therapy in ICR that is performed after cardiac surgery in Korean hospitals. Questionnaires modified by previous studies were sent to the departments of thoracic surgery of 10 hospitals in Korea. Nine replies (response rate 90%) were received. Eight nurses and one physiotherapist completed the questionnaire. Most of the education on wards after cardiac surgery was conducted by nurses. On postoperative day 1, four sites performed sitting on the edge of bed, sit to stand, up to chair, and walking in the ward. Only one site performed that exercise on postoperative day 2. One activity (stairs up and down) was performed on different days at only two sites. Patients received education preoperatively and predischarge for preventing complications and reducing muscle weakness through physical inactivity. The results of the study demonstrate that there are small variations in the general care provided by nurses after cardiac surgery. Based on the results of this research, we recommended that exercise therapy programs have to conduct by exercise specialists like exercise physiologists or physiotherapists for patients in hospitalization period.

Technique for producing cardiac radionuclide motion images

International Nuclear Information System (INIS)

Reese, I.C.; Mishkin, F.S.

1975-01-01

Sequential frames of different portions of the cardiac cycle are gated into a minicomputer by using an EKG signal recorded onto digital tape simultaneously with imaging information. Serial display of these frames on the computer oscilloscope or projection of 35-mm half frames of these images provides a cardiac motion image with information content adequate for qualitatively assessing cardiac motion. (U.S.)

Sudden Cardiac Arrest (SCA) Risk Assessment

Science.gov (United States)

... HRS Find a Specialist Share Twitter Facebook SCA Risk Assessment Sudden Cardiac Arrest (SCA) occurs abruptly and without ... people of all ages and health conditions. Start Risk Assessment The Sudden Cardiac Arrest (SCA) Risk Assessment Tool ...

Cardiac cell modelling: Observations from the heart of the cardiac physiome project

KAUST Repository

Fink, Martin; Niederer, Steven A.; Cherry, Elizabeth M.; Fenton, Flavio H.; Koivumä ki, Jussi T.; Seemann, Gunnar; Thul, Rü diger; Zhang, Henggui; Sachse, Frank B.; Beard, Dan; Crampin, Edmund J.; Smith, Nicolas P.

2011-01-01

In this manuscript we review the state of cardiac cell modelling in the context of international initiatives such as the IUPS Physiome and Virtual Physiological Human Projects, which aim to integrate computational models across scales and physics. In particular we focus on the relationship between experimental data and model parameterisation across a range of model types and cellular physiological systems. Finally, in the context of parameter identification and model reuse within the Cardiac Physiome, we suggest some future priority areas for this field. © 2010 Elsevier Ltd.

The cardiac patient in Ramadan.

Science.gov (United States)

Chamsi-Pasha, Majed; Chamsi-Pasha, Hassan

2016-01-01

Ramadan is one of the five fundamental pillars of Islam. During this month, the majority of the 1.6 billion Muslims worldwide observe an absolute fast from dawn to sunset without any drink or food. Our review shows that the impact of fasting during Ramadan on patients with stable cardiac disease is minimal and does not lead to any increase in acute events. Most patients with the stable cardiac disease can fast safely. Most of the drug doses and their regimen are easily manageable during this month and may need not to be changed. Ramadan fasting is a healthy nonpharmacological means for improving cardiovascular risk factors. Most of the Muslims, who suffer from chronic diseases, insist on fasting Ramadan despite being exempted by religion. The Holy Quran specifically exempts the sick from fasting. This is particularly relevant if fasting worsens one's illness or delays recovery. Patients with unstable angina, recent myocardial infarction, uncontrolled hypertension, decompensated heart failure, recent cardiac intervention or cardiac surgery or any debilitating diseases should avoid fasting.

Investigating patients' preferences for cardiac rehabilitation in Denmark

DEFF Research Database (Denmark)

Kjaer, Trine; Gyrd-Hansen, Dorte; Willaing, Ingrid

2006-01-01

the preferences for the offer of participation in various cardiac rehabilitation program activities: smoking cessation course, physical exercise program, personal meetings with cardiac nurse, group meetings managed by cardiac nurses, and nutritional counseling guidance. The questionnaire was sent to 742 former...

Social inequality in phase II cardiac rehabilitation attendance

DEFF Research Database (Denmark)

Pedersen, Maria; Egerod, Ingrid; Overgaard, Dorthe

2018-01-01

: Thirty per cent attended full cardiac rehabilitation. Patients with low educational attainment, comorbidities, long commute to cardiac rehabilitation centre, and lone dwelling were less likely to attend full cardiac rehabilitation, whereas patients with high anxiety and depression score were more likely...

Evaluation of Paradoxical Septal Motion Following Cardiac Surgery with Gated Cardiac Blood Pool Scan

International Nuclear Information System (INIS)

Shin, Seong Hae; Chung, June Key; Lee, Myung Chul; Cho, Bo Youn; Koh, Chang Soon; Suh, Kyung Phil

1985-01-01

The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload (that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients (that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

Evaluation of Paradoxical Septal Motion Following Cardiac Surgery with Gated Cardiac Blood Pool Scan

Energy Technology Data Exchange (ETDEWEB)

Shin, Seong Hae; Chung, June Key; Lee, Myung Chul; Cho, Bo Youn; Koh, Chang Soon; Suh, Kyung Phil [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1985-03-15

The development of paradoxical interventricular septal motion is a common consequence of cardiopulmonary bypass operation. The reason for this postoperative abnormal septal motion is not clear. 41 patients were studied preoperatively and postoperatively with radionuclide blood pool scan to evaluate the frequency of development of paradoxical septal motion with right ventricular volume overload before surgery and the frequency of development of paradoxical septal motion after cardiac surgery with cardiopulmonary bypass, and to evaluate the change of EF related to the development of paradoxical septal motion after cardiac surgery. The results were as follows; 1) 7 of 41 patients with right ventricular volume overload (that is 17%) showed paradoxical septal motion before surgery. But 13 of 34 patients (that is 42%) had paradoxical septal motion after cardiac surgery with cardiopulmonary bypass. So open heart surgery with cardiopulmonary bypass related the development of paradoxical septal motion after surgery. 2) EF significantly decreased in patients who developed paradoxical septal motion after surgery, whereas the EF did not change in the patients who retained normal interventricular septal motion after surgery. So paradoxical septal motion usually reflected some diminution of left ventricular function, immediately after cardiac surgery.

[Cardiac sarcoidosis: diagnostics, treatment and follow-up].

Science.gov (United States)

Dudziak, Maria; Jankowska, Hanna; Dorniak, Karolina

2018-03-27

Sarcoidosis is a generalised granulomatous disorder of unknown aetiology. Cardiac involvement may affect conduction system, myocardium, valvular apparatus and pericardium. Clinical spectrum ranges from asymptomatic involvement to sudden cardiac death. Patients with biopsy-proven extracardiac sarcoidosis should be screened for cardiac involvement (standard ECG, 24-hour Holter ECG, echocardiography) and in case of any abnormalities found on these tests, more advanced diagnostic methods should be used. Steroid treatment is still the mainstay of therapy in cardiac sarcoidosis. Several immunosuppresive agents are also effective and used in different combinations with steroids, as well as heart failure treatment (including ACE inhibitors, angiotensin receptor blockers, beta-blockers and diuretics). Advanced heart block requires pacemaker implantation, and implantable cardioverterdefibrillator is an effective treatment in primary and secondary prophylaxis of sudden cardiac death. Heart transplantation is considered in advanced, drug-resistant heart failure or incessant ventricular arrhythmias unresponsive to other forms of therapy. © 2018 MEDPRESS.

Cardiac catheterization

Science.gov (United States)

... tests. However, it is very safe when done by an experienced team. The risks include: Cardiac tamponade Heart attack Injury to a coronary artery Irregular heartbeat Low blood pressure Reaction to the contrast dye Stroke Possible complications ...

Cardiac hybrid imaging

Energy Technology Data Exchange (ETDEWEB)

Gaemperli, Oliver [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University Hospital Zurich, Nuclear Cardiology, Cardiovascular Center, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zurich (Switzerland)

2014-05-15

Hybrid cardiac single photon emission computed tomography (SPECT)/CT imaging allows combined assessment of anatomical and functional aspects of cardiac disease. In coronary artery disease (CAD), hybrid SPECT/CT imaging allows detection of coronary artery stenosis and myocardial perfusion abnormalities. The clinical value of hybrid imaging has been documented in several subsets of patients. In selected groups of patients, hybrid imaging improves the diagnostic accuracy to detect CAD compared to the single imaging techniques. Additionally, this approach facilitates functional interrogation of coronary stenoses and guidance with regard to revascularization procedures. Moreover, the anatomical information obtained from CT coronary angiography or coronary artery calcium scores (CACS) adds prognostic information over perfusion data from SPECT. The use of cardiac hybrid imaging has been favoured by the dissemination of dedicated hybrid systems and the release of dedicated image fusion software, which allow simple patient throughput for hybrid SPECT/CT studies. Further technological improvements such as more efficient detector technology to allow for low-radiation protocols, ultra-fast image acquisition and improved low-noise image reconstruction algorithms will be instrumental to further promote hybrid SPECT/CT in research and clinical practice. (orig.)

Cardiac Cachexia Syndrome

Directory of Open Access Journals (Sweden)

Teresa Raposo André

2017-10-01

Full Text Available Heart failure is a chronic, progressive, and incurable disease. Cardiac cachexia is a strong predictor of poor prognosis, regardless of other important variables. This review intends to gather evidence to enable recognition of cardiac cachexia, identification of early stages of muscle waste and sarcopenia, and improve identification of patients with terminal heart failure in need of palliative care, whose symptoms are no longer controlled by usual medical measures. The pathophysiology is complex and multifactorial. There are many treatment options to prevent or revert muscle waste and sarcopenia; although, these strategies are less effective in advanced stages of cardiac cachexia. In these final stages, symptomatic palliation plays an important role, focussing on the patient’s comfort and avoiding the ‘acute model’ treatment of aggressive, disproportionate, and inefficient care. In order to provide adequate care and attempt to prevent this syndrome, thus reducing its impact on healthcare, there should be improved communication between general practitioners, internal medicine physicians, cardiologists, and palliative care specialists since heart failure has an unforeseeable course and is associated with an increasing number of deaths and different levels of suffering.

"Just-In-Time" Simulation Training Using 3-D Printed Cardiac Models After Congenital Cardiac Surgery.

Science.gov (United States)

Olivieri, Laura J; Su, Lillian; Hynes, Conor F; Krieger, Axel; Alfares, Fahad A; Ramakrishnan, Karthik; Zurakowski, David; Marshall, M Blair; Kim, Peter C W; Jonas, Richard A; Nath, Dilip S

2016-03-01

High-fidelity simulation using patient-specific three-dimensional (3D) models may be effective in facilitating pediatric cardiac intensive care unit (PCICU) provider training for clinical management of congenital cardiac surgery patients. The 3D-printed heart models were rendered from preoperative cross-sectional cardiac imaging for 10 patients undergoing congenital cardiac surgery. Immediately following surgical repair, a congenital cardiac surgeon and an intensive care physician conducted a simulation training session regarding postoperative care utilizing the patient-specific 3D model for the PCICU team. After the simulation, Likert-type 0 to 10 scale questionnaire assessed participant perception of impact of the training session. Seventy clinicians participated in training sessions, including 22 physicians, 38 nurses, and 10 ancillary care providers. Average response to whether 3D models were more helpful than standard hand off was 8.4 of 10. Questions regarding enhancement of understanding and clinical ability received average responses of 9.0 or greater, and 90% of participants scored 8 of 10 or higher. Nurses scored significantly higher than other clinicians on self-reported familiarity with the surgery (7.1 vs. 5.8; P = .04), clinical management ability (8.6 vs. 7.7; P = .02), and ability enhancement (9.5 vs. 8.7; P = .02). Compared to physicians, nurses and ancillary providers were more likely to consider 3D models more helpful than standard hand off (8.7 vs. 7.7; P = .05). Higher case complexity predicted greater enhancement of understanding of surgery (P = .04). The 3D heart models can be used to enhance congenital cardiac critical care via simulation training of multidisciplinary intensive care teams. Benefit may be dependent on provider type and case complexity. © The Author(s) 2016.

[Thromboelastography and its use in cardiac surgery].

Science.gov (United States)

Ak, Koray; Atalan, Nazan; Tekeli, Atike; Işbir, Selim; Civelek, Ali; Emekli, Nesrin; Arsan, Sinan

2008-04-01

Thromboelastography is an alternative method to conventional coagulation tests for the general evaluation of hemostatic system. Cardiac surgery with cardiopulmonary bypass is accomplished by complex alterations of hemostasis, including acquired dysfunction of platelets, consumption coagulopathy and increased fibrinolysis. Despite major advances in blood conservation methods and perioperative care of the patients, transfusion rates in cardiac surgery remain high. Thromboelastography has an ability to assess almost all components of haemostatic system globally. Currently, thromboelastography is used with standard coagulation tests to decrease the microvascular bleeding and homologous blood transfusion in cardiac surgery with cardiopulmonary bypass. In this review, we aimed to discuss thromboelastography technology and its usage in cardiac surgery.

Radiation exposure of children during cardiac catheterisation

International Nuclear Information System (INIS)

Popp, W.

1979-01-01

It is well known that in adults, cardiac catheterisation involves the highest possible radiation exposure for a single examination. The paper now investigates the radiation exposure in paediatric cardiac cathetrisations. Dosimeters attached to the children during the examination were used as well as phantom measurements under the conditions of cardiac catheterisation. With the aid of the phantom, also the total energy absorption during an examination procedure was determined. This value was estimated to be 80 mJ. In spite of the high individual exposure, the contribution to the population exposure is low due to the small number of cardiac catheterisations. (orig.) 891 AJ/orig. 892 MKO [de

Cardiac Intensive Care Unit Management of Patients After Cardiac Arrest: Now the Real Work Begins.

Science.gov (United States)

Randhawa, Varinder K; Grunau, Brian E; Debicki, Derek B; Zhou, Jian; Hegazy, Ahmed F; McPherson, Terry; Nagpal, A Dave

2018-02-01

Survival with a good quality of life after cardiac arrest continues to be abysmal. Coordinated resuscitative care does not end with the effective return of spontaneous circulation (ROSC)-in fact, quite the contrary is true. Along with identifying and appropriately treating the precipitating cause, various components of the post-cardiac arrest syndrome also require diligent observation and management, including post-cardiac arrest neurologic injury and myocardial dysfunction, systemic ischemia-reperfusion phenomenon with potential consequent multiorgan failure, and the various sequelae of critical illness. There is growing evidence that an early invasive approach to coronary reperfusion with percutaneous coronary intervention, together with active targeted temperature management and optimization of hemodynamic, ventilator, and metabolic parameters, may improve survival and neurologic outcomes in cardiac arrest survivors. Neuroprognostication is complex, as are survivorship issues and long-term rehabilitation. Our paramedics, emergency physicians, and resuscitation specialists are all to be congratulated for ever-increasing success with ROSC… but now the real work begins. Copyright © 2017 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

Cardiac findings in 31 patients with Noonan's syndrome

Directory of Open Access Journals (Sweden)

Bertola Débora Romeo

2000-01-01

Full Text Available OBJECTIVE: To evaluate cardiac findings in 31 Noonan syndrome patients. METHODS: Thirty-one (18 males and 13 femalespatients from 26 families affected with Noonan's syndrome were evaluated from the cardiac point of view with electrocardiography and echodopplercardiography. RESULTS: Twenty patients had some type of cardiac abnormality. The most frequent was pulmonary valve stenosis followed by hypertrophic myocardiopathy, commonly associated with valve defects. Upper deviation of the QRS axis was observed in 80% of these patients. CONCLUSION: In view of the high frequency and diversity of cardiac abnormalities present in Noonan syndrome, cardiac evaluation with electrocardiography and echocardiography should be performed in all patients diagnostically suspected of having this disease.

Drug-Induced Rhabdomyolysis with Elevated Cardiac Troponin T

Directory of Open Access Journals (Sweden)

Gro Egholm

2015-01-01

Full Text Available The essential role of cardiac troponin in the diagnosis of acute myocardial infarction has led to the development of high-sensitivity assays, which are able to detect very small amounts of myocardial necrosis. The high-sensitivity cardiac troponin T assay, however, is not entirely specific for myocardial injury. This case report describes a 48-year-old woman, who, two years after cardiac transplantation, presented with rhabdomyolysis. During the course of the disease, her troponin T level was elevated on repeated occasions, but other definitive evidence of myocardial injury was not found. Asymptomatic cardiac troponin T elevations during rhabdomyolysis may be due to either cardiac involvement or false positive results stemming from skeletal muscle injury.

J Waves for Predicting Cardiac Events in Hypertrophic Cardiomyopathy.

Science.gov (United States)

Tsuda, Toyonobu; Hayashi, Kenshi; Konno, Tetsuo; Sakata, Kenji; Fujita, Takashi; Hodatsu, Akihiko; Nagata, Yoji; Teramoto, Ryota; Nomura, Akihiro; Tanaka, Yoshihiro; Furusho, Hiroshi; Takamura, Masayuki; Kawashiri, Masa-Aki; Fujino, Noboru; Yamagishi, Masakazu

2017-10-01

This study sought to investigate whether the presence of J waves was associated with cardiac events in patients with hypertrophic cardiomyopathy (HCM). It has been uncertain whether the presence of J waves predicts life-threatening cardiac events in patients with HCM. This study evaluated consecutive 338 patients with HCM (207 men; age 61 ± 17 years of age). A J-wave was defined as J-point elevation >0.1 mV in at least 2 contiguous inferior and/or lateral leads. Cardiac events were defined as sudden cardiac death, ventricular fibrillation or sustained ventricular tachycardia, or appropriate implantable cardiac defibrillator therapy. The study also investigated whether adding the J-wave in a conventional risk model improved a prediction of cardiac events. J waves were seen in 46 (13.6%) patients at registration. Cardiac events occurred in 31 patients (9.2%) during median follow-up of 4.9 years (interquartile range: 2.6 to 7.1 years). In a Cox proportional hazards model, the presence of J waves was significantly associated with cardiac events (adjusted hazard ratio: 4.01; 95% confidence interval [CI]: 1.78 to 9.05; p = 0.001). Compared with the conventional risk model, the model using J waves in addition to conventional risks better predicted cardiac events (net reclassification improvement, 0.55; 95% CI: 0.20 to 0.90; p = 0.002). The presence of J waves was significantly associated with cardiac events in HCM. Adding J waves to conventional cardiac risk factors improved prediction of cardiac events. Further confirmatory studies are needed before considering J-point elevation as a marker of risk for use in making management decisions regarding risk in patients with HCM. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Left and right ventricle assessment with Cardiac CT: validation study vs. Cardiac MR

Energy Technology Data Exchange (ETDEWEB)

Maffei, Erica; Seitun, Sara [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Messalli, Giancarlo; Catalano, Onofrio [SDN Foundation - IRCCS, Naples (Italy); Martini, Chiara; Cademartiri, Filippo [Giovanni XXIII Hospital, Cardiovascular Radiology Unit, Monastier di Treviso (Italy); Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Nieman, Koen; Rossi, Alexia; Mollet, Nico R. [Erasmus Medical Center, Department of Radiology and Cardiology, Rotterdam (Netherlands); Guaricci, Andrea I. [Azienda Ospedaliero-Universitaria di Foggia, Department of Cardiology, Foggia (Italy); Tedeschi, Carlo [Ospedale San Gennaro, Department of Cardiology, Naples (Italy)

2012-05-15

To compare Magnetic Resonance (MR) and Computed Tomography (CT) for the assessment of left (LV) and right (RV) ventricular functional parameters. Seventy nine patients underwent both Cardiac CT and Cardiac MR. Images were acquired using short axis (SAX) reconstructions for CT and 2D cine b-SSFP (balanced-steady state free precession) SAX sequence for MR, and evaluated using dedicated software. CT and MR images showed good agreement: LV EF (Ejection Fraction) (52 {+-} 14% for CT vs. 52 {+-} 14% for MR; r = 0.73; p > 0.05); RV EF (47 {+-} 12% for CT vs. 47 {+-} 12% for MR; r = 0.74; p > 0.05); LV EDV (End Diastolic Volume) (74 {+-} 21 ml/m{sup 2} for CT vs. 76 {+-} 25 ml/m{sup 2} for MR; r = 0.59; p > 0.05); RV EDV (84 {+-} 25 ml/m{sup 2} for CT vs. 80 {+-} 23 ml/m{sup 2} for MR; r = 0.58; p > 0.05); LV ESV (End Systolic Volume)(37 {+-} 19 ml/m{sup 2} for CT vs. 38 {+-} 23 ml/m{sup 2} for MR; r = 0.76; p > 0.05); RV ESV (46 {+-} 21 ml/m{sup 2} for CT vs. 43 {+-} 18 ml/m{sup 2} for MR; r = 0.70; p > 0.05). Intra- and inter-observer variability were good, and the performance of CT was maintained for different EF subgroups. Cardiac CT provides accurate and reproducible LV and RV volume parameters compared with MR, and can be considered as a reliable alternative for patients who are not suitable to undergo MR. circle Cardiac-CT is able to provide Left and Right Ventricular function. circle Cardiac-CT is accurate as MR for LV and RV volume assessment. (orig.)

Improved bioavailability of targeted Curcumin delivery efficiently regressed cardiac hypertrophy by modulating apoptotic load within cardiac microenvironment

International Nuclear Information System (INIS)

Ray, Aramita; Rana, Santanu; Banerjee, Durba; Mitra, Arkadeep; Datta, Ritwik; Naskar, Shaon; Sarkar, Sagartirtha

2016-01-01

Cardiomyocyte apoptosis acts as a prime modulator of cardiac hypertrophy leading to heart failure, a major cause of human mortality worldwide. Recent therapeutic interventions have focussed on translational applications of diverse pharmaceutical regimes among which, Curcumin (from Curcuma longa) is known to have an anti-hypertrophic potential but with limited pharmacological efficacies due to low aqueous solubility and poor bioavailability. In this study, Curcumin encapsulated by carboxymethyl chitosan (CMC) nanoparticle conjugated to a myocyte specific homing peptide was successfully delivered in bioactive form to pathological myocardium for effective regression of cardiac hypertrophy in a rat (Rattus norvegicus) model. Targeted nanotization showed higher cardiac bioavailability of Curcumin at a low dose of 5 mg/kg body weight compared to free Curcumin at 35 mg/kg body weight. Moreover, Curcumin/CMC-peptide treatment during hypertrophy significantly improved cardiac function by downregulating expression of hypertrophy marker genes (ANF, β-MHC), apoptotic mediators (Bax, Cytochrome-c) and activity of apoptotic markers (Caspase 3 and PARP); whereas free Curcumin in much higher dose showed minimal improvement during compromised cardiac function. Targeted Curcumin treatment significantly lowered p53 expression and activation in diseased myocardium via inhibited interaction of p53 with p300-HAT. Thus attenuated acetylation of p53 facilitated p53 ubiquitination and reduced the apoptotic load in hypertrophied cardiomyocytes; thereby limiting cardiomyocytes' need to enter the regeneration cycle during hypertrophy. This study elucidates for the first time an efficient targeted delivery regimen for Curcumin and also attributes towards probable mechanistic insight into its therapeutic potential as a cardio-protective agent for regression of cardiac hypertrophy. - Highlights: • Cardiomyocyte targeted Curcumin/CMC-peptide increases bioavailability of the drug. �

Making an APPropriate Care Program for Indigenous Cardiac Disease: Customization of an Existing Cardiac Rehabilitation Program.

Science.gov (United States)

Bradford, DanaKai; Hansen, David; Karunanithi, Mohan

2015-01-01

Cardiovascular disease is a major health problem for all Australians and is the leading cause of death in Aboriginal and Torres Strait Islanders. In 2010, more then 50% of all heart attack deaths were due to repeated events. Cardiac rehabilitation programs have been proven to be effective in preventing the recurrence of cardiac events and readmission to hospitals. There are however, many barriers to the use of these programs. To address these barriers, CSIRO developed an IT enabled cardiac rehabilitation program delivered by mobile phone through a smartphone app and succesfully trialed it in an urban general population. If these results can be replicated in Indigenous populations, the program has the potential to significantly improve life expectancy and help close the gap in health outcomes. The challenge described in this paper is customizing the existing cardiac health program to make it culturally relevant and suitable for Indigenous Australians living in urban and remote communities.

Cardiac rhabdomyoma associated with tuberosclerosis complex in a newborn

Directory of Open Access Journals (Sweden)

Birgin Torer

2016-03-01

Full Text Available Cardiac rhabdomyomas are the most comman cardiac tumors in children. They are hamartomatous benign tumors composed of myocytes. They often presents as multiple lesions involving the ventricular cavities. Rhabdomyomas are usually detected in utero by fetal echocardiography. Although patients with cardiac rhabdomyomas are generally asymptomatic these tumors may cause heart failure, severe arrhyhmias and sudden death. Cardiac rhabdomyomas are often associated with tuberosclerosis and they may be the earliest manifestation of tuberosclerosis. Here, we report a newborn infant with antenatally detected cardiac rhabdomyomas associated with tuberosclerosis and we want to emphasize that other diagnostic features of tuberosclerosis should be evaluated in patients with cardiac rhabdomyomas. [Cukurova Med J 2016; 41(0.100: 56-59

Use of I-123 MIBG cardiac scintigraphy to assess the impact of carvedilol on cardiac adrenergic neuronal function in childhood dilated cardiomyopathy

International Nuclear Information System (INIS)

Maunoury, C.; Acar, P.; Sidi, D.

2006-01-01

I-123 MIBG cardiac scintigraphy is a useful tool to assess cardiac adrenergic neuronal function, which is impaired in children with dilated cardiomyopathy (DCM). In adults with DCM, long-term treatment with carvedilol improves both cardiac adrenergic neuronal function and left ventricular function. The aim of this prospective study was to evaluate the impact of carvedilol on cardiac adrenergic neuronal function and on left ventricular function in seventeen patients (11 female, 6 male, mean age 39 ± 57 months, range 1 - 168 months) with DCM. All patients underwent I-123 MIBG cardiac scintigraphy and equilibrium radio-nuclide angiography before and after a 6 month period of carvedilol therapy. A static anterior view of the chest was acquired 4 hours after intravenous injection of 20 to 75 MBq of I-123 MIBG. Cardiac neuronal uptake of I-123 MIBG was measured using the heart to mediastinum count ratio (HMR). Radionuclide left ventricular ejection fraction (LVEF) was assessed following a standard protocol. There was no major cardiac events (death or transplantation) during the follow-up period. I-123 MIBG cardiac uptake and left ventricular function respectively increased by 38% and 65% after 6 months of treatment with carvedilol (HMR 223 ± 49% vs 162 ± 26%, p < 0.0001 and LVEF = 43 ± 17% vs 26 ± 11%, p < 0.0001). Carvedilol can improve cardiac adrenergic neuronal function and left ventricular function in children with DCM. Further studies are needed to assess the relationship between improvement in I-123 MIBG cardiac uptake and the beneficial effects of carvedilol on morbidity and mortality. (authors)

Post cardiac injury syndrome

DEFF Research Database (Denmark)

Nielsen, S L; Nielsen, F E

1991-01-01

The post-pericardiotomy syndrome is a symptom complex which is similar in many respects to the post-myocardial infarction syndrome and these are summarized under the diagnosis of the Post Cardiac Injury Syndrome (PCIS). This condition, which is observed most frequently after open heart surgery, i...... on the coronary vessels, with cardiac tamponade and chronic pericardial exudate. In the lighter cases, PCIS may be treated with NSAID and, in the more severe cases, with systemic glucocorticoid which has a prompt effect....

Assessment of cardiac sympathetic nerve integrity with positron emission tomography

International Nuclear Information System (INIS)

Raffel, David M.; Wieland, Donald M.

2001-01-01

The autonomic nervous system plays a critical role in the regulation of cardiac function. Abnormalities of cardiac innervation have been implicated in the pathophysiology of many heart diseases, including sudden cardiac death and congestive heart failure. In an effort to provide clinicians with the ability to regionally map cardiac innervation, several radiotracers for imaging cardiac sympathetic neurons have been developed. This paper reviews the development of neuronal imaging agents and discusses their emerging role in the noninvasive assessment of cardiac sympathetic innervation

Postnatal ablation of Foxm1 from cardiomyocytes causes late onset cardiac hypertrophy and fibrosis without exacerbating pressure overload-induced cardiac remodeling.

Directory of Open Access Journals (Sweden)

Craig Bolte

Full Text Available Heart disease remains a leading cause of morbidity and mortality in the industrialized world. Hypertrophic cardiomyopathy is the most common genetic cardiovascular disorder and the most common cause of sudden cardiac death. Foxm1 transcription factor (also known as HFH-11B, Trident, Win or MPP2 plays an important role in the pathogenesis of various cancers and is a critical mediator of post-injury repair in multiple organs. Foxm1 has been previously shown to be essential for heart development and proliferation of embryonic cardiomyocytes. However, the role of Foxm1 in postnatal heart development and in cardiac injury has not been evaluated. To delete Foxm1 in postnatal cardiomyocytes, αMHC-Cre/Foxm1(fl/fl mice were generated. Surprisingly, αMHC-Cre/Foxm1(fl/fl mice exhibited normal cardiomyocyte proliferation at postnatal day seven and had no defects in cardiac structure or function but developed cardiac hypertrophy and fibrosis late in life. The development of cardiomyocyte hypertrophy and cardiac fibrosis in aged Foxm1-deficient mice was associated with reduced expression of Hey2, an important regulator of cardiac homeostasis, and increased expression of genes critical for cardiac remodeling, including MMP9, αSMA, fibronectin and vimentin. We also found that following aortic constriction Foxm1 mRNA and protein were induced in cardiomyocytes. However, Foxm1 deletion did not exacerbate cardiac hypertrophy or fibrosis following chronic pressure overload. Our results demonstrate that Foxm1 regulates genes critical for age-induced cardiomyocyte hypertrophy and cardiac fibrosis.

Cardiac complications in diphtheria and predictors of outcomes.

Science.gov (United States)

Samdani, Sunil; Jain, Avani; Meena, Vinod; Meena, C B

2018-01-01

To study the cardiac complications in diphtheria patients and to study the predictors of outcomes. Single centre prospective analysis of cardiac complications in diphtheria patients. In this study, there were 60 patients diagnosed with diphtheria with ECG changes. The ECG changes seen were sinus tachycardia (68.3%), T wave inversion (20%), ST segment depression (13.3%), right bundle branch block (5%), multiple atrial ectopics (3.3%). The case fatality rate in our study was 25% (15 patients). High CPK-MB, myoglobulin and cardiac troponin levels were associated with cardiac mortality. In our study, cardiac troponin T had the highest sensitivity (80%) and CK-MB had the highest specificity (95.56%). Cardiac involvement is a common complication of infection with C. diphtheria and is associated with high mortality. As diphtheria can be prevented by adequate vaccination, efforts should be maximized for high vaccine coverage with booster doses. Copyright © 2017. Published by Elsevier B.V.

Implementing a Cardiac Skills Orientation and Simulation Program.

Science.gov (United States)

Hemingway, Maureen W; Osgood, Patrice; Mannion, Mildred

2018-02-01

Patients with cardiac morbidities admitted for cardiac surgical procedures require perioperative nurses with a high level of complex nursing skills. Orienting new cardiac team members takes commitment and perseverance in light of variable staffing levels, high-acuity patient populations, an active cardiac surgical schedule, and the unpredictability of scheduling patients undergoing cardiac transplantation. At an academic medical center in Boston, these issues presented opportunities to orient new staff members to the scrub person role, but hampered efforts to provide active learning opportunities in a safe environment. As a result, facility personnel created a program to increase new staff members' skills, confidence, and proficiency, while also increasing the number of staff members who were proficient at scrubbing complex cardiac procedures. To address the safe learning requirement, personnel designed a simulation program to provide scrubbing experience, decrease orientees' supervision time, and increase staff members' confidence in performing the scrub person role. © AORN, Inc, 2018.

Influence of the timing of cardiac catheterization and amount of contrast media on acute renal failure after cardiac surgery

Directory of Open Access Journals (Sweden)

Mohsen Mirmohammad Sadeghi

2011-01-01

Full Text Available Background: There is limited data about the influence of timing of cardiac surgery in relation to diagnostic angiography and/or the impact of the amount of contrast media used during angiography on the occurance of acute renal failure (ARF. Therefore, in the present study the effect of the time interval between diagnostic angiography and cardiac surgery and also the amount of contrast media used during the diagnostic procedure on the incidence of ARF after cardiac surgery was investigated. Methods: Data of 1177 patients who underwent different types of cardiac surgeries after cardiac catheterization were prospectively examined. The influence of time interval between cardiac catheterization and surgery as well as the amount of contrast agent on postoperative ARF were assessed using multivariable logistic regression. Results: The patients who progressed to ARF were more likely to have received a higher dose of contrast agent compared to the mean dose. However, the time interval between cardiac surgery and last catheterization was not significantly different between the patients with and without ARF (p = 0.05. Overall, postoperative peak creatinine was highest on day 0, then decreased and remained significantly unchanged after this period. Overall prevalence of acute renal failure during follow-up period had a changeable trend and had the highest rates in days 1 (53.57% and 6 (52.17% after surgery. Combined coronary bypass and valve surgery were the strongest predictor of postoperative ARF (OR: 4.976, CI = 1.613-15.355 and p = 0.002, followed by intra-aortic balloon pump insertion (OR: 6.890, CI = 1.482-32.032 and p = 0.009 and usage of higher doses of contrast media agent (OR: 1.446, CI = 1.033-2.025 and p = 0.031. Conclusions: Minimizing the amount of contrast agent has a potential role in reducing the incidence of postoperative ARF in patients undergoing cardiac surgery, but delaying cardiac surgery after exposure to these agents might not have

Influence of the timing of cardiac catheterization and amount of contrast media on acute renal failure after cardiac surgery.

Science.gov (United States)

Sadeghi, Mohsen Mirmohammad; Gharipour, Mojgan; Nilforoush, Peiman; Shamsolkotabi, Hamid; Sadeghi, Hamid Mirmohammad; Kiani, Amjad; Sadeghi, Pouya Mirmohammad; Farahmand, Niloufar

2011-04-01

There is limited data about the influence of timing of cardiac surgery in relation to diagnostic angiography and/or the impact of the amount of contrast media used during angiography on the occurance of acute renal failure (ARF). Therefore, in the present study the effect of the time interval between diagnostic angiography and cardiac surgery and also the amount of contrast media used during the diagnostic procedure on the incidence of ARF after cardiac surgery was investigated. Data of 1177 patients who underwent different types of cardiac surgeries after cardiac catheterization were prospectively examined. The influence of time interval between cardiac catheterization and surgery as well as the amount of contrast agent on postoperative ARF were assessed using multivariable logistic regression. The patients who progressed to ARF were more likely to have received a higher dose of contrast agent compared to the mean dose. However, the time interval between cardiac surgery and last catheterization was not significantly different between the patients with and without ARF (p = 0.05). Overall, postoperative peak creatinine was highest on day 0, then decreased and remained significantly unchanged after this period. Overall prevalence of acute renal failure during follow-up period had a changeable trend and had the highest rates in days 1 (53.57%) and 6 (52.17%) after surgery. Combined coronary bypass and valve surgery were the strongest predictor of postoperative ARF (OR: 4.976, CI = 1.613-15.355 and p = 0.002), followed by intra-aortic balloon pump insertion (OR: 6.890, CI = 1.482-32.032 and p = 0.009) and usage of higher doses of contrast media agent (OR: 1.446, CI = 1.033-2.025 and p = 0.031). Minimizing the amount of contrast agent has a potential role in reducing the incidence of postoperative ARF in patients undergoing cardiac surgery, but delaying cardiac surgery after exposure to these agents might not have this protective effect.

Plasma membrane characterization, by scanning electron microscopy, of multipotent myoblasts-derived populations sorted using dielectrophoresis

Energy Technology Data Exchange (ETDEWEB)

Muratore, Massimo, E-mail: M.Muratore@ed.ac.uk [Institute of Integrated Micro and Nano System, School of Engineering, The University of Edinburgh, Edinburgh EH9 3JF (United Kingdom); Mitchell, Steve [Institute of Molecular Plant Science, School of Biological Science, The University of Edinburgh, Edinburgh EH9 3JF (United Kingdom); Waterfall, Martin [Institute of Immunology and Infection Research, School of Biological Science, The University of Edinburgh, Edinburgh EH9 3JT (United Kingdom)

2013-09-06

Highlights: •Dielectrophoretic separation/sorting of multipotent cells. •Plasma membrane microvilli structure of C2C12 and fibroblasts by SEM microscopy. •Cell cycle determination by Ki-67 in DEP-sorted cells. •Plasma membrane differences responsible for changes in membrane capacitance. -- Abstract: Multipotent progenitor cells have shown promise for use in biomedical applications and regenerative medicine. The implementation of such cells for clinical application requires a synchronized, phenotypically and/or genotypically, homogenous cell population. Here we have demonstrated the implementation of a biological tag-free dielectrophoretic device used for discrimination of multipotent myoblastic C2C12 model. The multipotent capabilities in differentiation, for these cells, diminishes with higher passage number, so for cultures above 70 passages only a small percentage of cells is able to differentiate into terminal myotubes. In this work we demonstrated that we could recover, above 96% purity, specific cell types from a mixed population of cells at high passage number without any biological tag using dielectrophoresis. The purity of the samples was confirmed by cytometric analysis using the cell specific marker embryonic myosin. To further investigate the dielectric properties of the cell plasma membrane we co-culture C2C12 with similar size, when in suspension, GFP-positive fibroblast as feeder layer. The level of separation between the cell types was above 98% purity which was confirmed by flow cytometry. These levels of separation are assumed to account for cell size and for the plasma membrane morphological differences between C2C12 and fibroblast unrelated to the stages of the cell cycle which was assessed by immunofluorescence staining. Plasma membrane conformational differences were further confirmed by scanning electron microscopy.

Plasma membrane characterization, by scanning electron microscopy, of multipotent myoblasts-derived populations sorted using dielectrophoresis

International Nuclear Information System (INIS)

Muratore, Massimo; Mitchell, Steve; Waterfall, Martin

2013-01-01

Highlights: •Dielectrophoretic separation/sorting of multipotent cells. •Plasma membrane microvilli structure of C2C12 and fibroblasts by SEM microscopy. •Cell cycle determination by Ki-67 in DEP-sorted cells. •Plasma membrane differences responsible for changes in membrane capacitance. -- Abstract: Multipotent progenitor cells have shown promise for use in biomedical applications and regenerative medicine. The implementation of such cells for clinical application requires a synchronized, phenotypically and/or genotypically, homogenous cell population. Here we have demonstrated the implementation of a biological tag-free dielectrophoretic device used for discrimination of multipotent myoblastic C2C12 model. The multipotent capabilities in differentiation, for these cells, diminishes with higher passage number, so for cultures above 70 passages only a small percentage of cells is able to differentiate into terminal myotubes. In this work we demonstrated that we could recover, above 96% purity, specific cell types from a mixed population of cells at high passage number without any biological tag using dielectrophoresis. The purity of the samples was confirmed by cytometric analysis using the cell specific marker embryonic myosin. To further investigate the dielectric properties of the cell plasma membrane we co-culture C2C12 with similar size, when in suspension, GFP-positive fibroblast as feeder layer. The level of separation between the cell types was above 98% purity which was confirmed by flow cytometry. These levels of separation are assumed to account for cell size and for the plasma membrane morphological differences between C2C12 and fibroblast unrelated to the stages of the cell cycle which was assessed by immunofluorescence staining. Plasma membrane conformational differences were further confirmed by scanning electron microscopy

Isolated Cardiac Hydatid Cyst

International Nuclear Information System (INIS)

Shakil, U.; Rehman, A. U.; Shahid, R.

2015-01-01

Hydatid cyst disease is common in our part of the world. Cardiac hydatid cyst is its rare manifestation. We report this case of 48-year male having isolated cardiac hydatid cyst, incidentally found on computed tomography. This patient presented in medical OPD of Combined Military Hospital, Lahore with one month history of mild retrosternal discomfort. His general physical and systemic examinations as well as ECG were unremarkable. Chest X-ray showed an enlarged cardiac shadow with mildly irregular left heart border. Contrast enhanced CT scan of the chest showed a large well defined multiloculated non-enhancing cystic lesion with multiple daughter cysts involving wall of left ventricle and overlying pericardium. Serology for echinococcus confirmed the diagnosis of hydatid cyst. Patient was offered the surgical treatment but he opted for medical treatment only. Albendezol was prescribed. His follow-up echocardiography after one month showed no significant decrease in size of the cyst. (author)

Hypokalemia and sudden cardiac death

DEFF Research Database (Denmark)

Kjeldsen, Keld

2010-01-01

Worldwide, approximately three million people suffer sudden cardiac death annually. These deaths often emerge from a complex interplay of substrates and triggers. Disturbed potassium homeostasis among heart cells is an example of such a trigger. Thus, hypokalemia and, also, more transient...... of fatal arrhythmia and sudden cardiac death a patient is, the more attention should be given to the potassium homeostasis....

Real-time MRI guidance of cardiac interventions.

Science.gov (United States)

Campbell-Washburn, Adrienne E; Tavallaei, Mohammad A; Pop, Mihaela; Grant, Elena K; Chubb, Henry; Rhode, Kawal; Wright, Graham A

2017-10-01

Cardiac magnetic resonance imaging (MRI) is appealing to guide complex cardiac procedures because it is ionizing radiation-free and offers flexible soft-tissue contrast. Interventional cardiac MR promises to improve existing procedures and enable new ones for complex arrhythmias, as well as congenital and structural heart disease. Guiding invasive procedures demands faster image acquisition, reconstruction and analysis, as well as intuitive intraprocedural display of imaging data. Standard cardiac MR techniques such as 3D anatomical imaging, cardiac function and flow, parameter mapping, and late-gadolinium enhancement can be used to gather valuable clinical data at various procedural stages. Rapid intraprocedural image analysis can extract and highlight critical information about interventional targets and outcomes. In some cases, real-time interactive imaging is used to provide a continuous stream of images displayed to interventionalists for dynamic device navigation. Alternatively, devices are navigated relative to a roadmap of major cardiac structures generated through fast segmentation and registration. Interventional devices can be visualized and tracked throughout a procedure with specialized imaging methods. In a clinical setting, advanced imaging must be integrated with other clinical tools and patient data. In order to perform these complex procedures, interventional cardiac MR relies on customized equipment, such as interactive imaging environments, in-room image display, audio communication, hemodynamic monitoring and recording systems, and electroanatomical mapping and ablation systems. Operating in this sophisticated environment requires coordination and planning. This review provides an overview of the imaging technology used in MRI-guided cardiac interventions. Specifically, this review outlines clinical targets, standard image acquisition and analysis tools, and the integration of these tools into clinical workflow. 1 Technical Efficacy: Stage 5 J

Stem cell sources for cardiac regeneration

NARCIS (Netherlands)

Roccio, M.; Goumans, M. J.; Sluijter, J. P. G.; Doevendans, P. A.

Cell-based cardiac repair has the ambitious aim to replace the malfunctioning cardiac muscle developed after myocardial infarction, with new contractile cardiomyocytes and vessels. Different stem cell populations have been intensively studied in the last decade as a potential source of new

Blunt traumatic cardiac rupture: therapeutic options and outcomes.

Science.gov (United States)

Nan, Yu-Yun; Lu, Ming-Shian; Liu, Kuo-Sheng; Huang, Yao-Kuang; Tsai, Feng-Chun; Chu, Jaw-Ji; Lin, Pyng Jing

2009-09-01

Cardiac rupture following blunt thoracic trauma is rarely encountered by clinicians, since it commonly causes death at the scene. With advances in traumatology, blunt cardiac rupture had been increasingly disclosed in various ways. This study reviews our experience of patients with suspected blunt traumatic cardiac rupture and proposes treatment protocols for the same. This is a 5-year retrospective study of trauma patients confirmed with blunt traumatic cardiac rupture admitted to a university-affiliated tertiary trauma referral centre. The following information was collected from the patients: age, sex, mechanism of injury, initial effective diagnostic tool used for diagnosing blunt cardiac rupture, location and size of the cardiac injury, associated injury and injury severity score (ISS), reversed trauma score (RTS), survival probability of trauma and injury severity scoring (TRISS), vital signs and biochemical lab data on arrival at the trauma centre, time elapsed from injury to diagnosis and surgery, surgical details, hospital course and final outcome. The study comprised 8 men and 3 women with a median age of 39 years (range: 24-73 years) and the median follow-up was 5.5 months (range: 1-35 months). The ISS, RTS, and TRISS scores of the patients were 32.18+/-5.7 (range: 25-43), 6.267+/-1.684 (range: 2.628-7.841), and 72.4+/-25.6% (range: 28.6-95.5%), respectively. Cardiac injuries were first detected using focused assessment with sonography for trauma (FAST) in 4 (36.3%) patients, using transthoracic echocardiography in 3 (27.3%) patients, chest CT in 1 (9%) patient, and intra-operatively in 3 (27.3%) patients. The sites of cardiac injury comprised the superior vena cava/right atrium junction (n=4), right atrial auricle (n=1), right ventricle (n=4), left ventricular contusion (n=1), and diffuse endomyocardial dissection over the right and left ventricles (n=1). Notably, 2 had pericardial lacerations presenting as a massive haemothorax, which initially masked

NUCLEAR IMAGING IN THE DIAGNOSIS OF CARDIAC AMYLOIDOSIS

Directory of Open Access Journals (Sweden)

V. B. Sergienko

2018-01-01

Full Text Available Histological analysis of endomyocardial tissue is still the gold standard for the diagnosis of cardiac amyloidosis but has its limitations. Accordingly, there is a need for noninvasive techniques to cardiac amyloidosis diagnostics. Echocardiography and magnetic resonance imaging can show characteristics which may not be very specific for cardiac amyloid. Recently, new opportunities of nuclear imaging in risk stratification and assessment of prognosis for patients with cardiac amyloidosis have appeared. During the last two decades different classes of radiopharmaceuticals have been developed based on compounds tropic to the components of amyloid infiltrates. In this paper we describe the current possibilities and perspectives of nuclear medicine techniques in patients with cardiac amyloidosis, including osteotropic and neurotropic scintigraphy, single-photon and positron emission tomography

Peripheral vasodilatation determines cardiac output in exercising humans

DEFF Research Database (Denmark)

Bada, A A; Svendsen, J H; Secher, N H

2012-01-01

In dogs, manipulation of heart rate has no effect on the exercise-induced increase in cardiac output. Whether these findings apply to humans remain uncertain, because of the large differences in cardiovascular anatomy and regulation. To investigate the role of heart rate and peripheral...... arterial ATP infusion at rest. Exercise and ATP infusion increased cardiac output, leg blood flow and vascular conductance (P heart rate by up to 54 beats min(−1), cardiac output did not change in any of the three...... demonstrate that the elevated cardiac output during steady-state exercise is regulated by the increase in skeletal muscle blood flow and venous return to the heart, whereas the increase in heart rate appears to be secondary to the regulation of cardiac output....

Mechanical perturbation control of cardiac alternans

Science.gov (United States)

Hazim, Azzam; Belhamadia, Youssef; Dubljevic, Stevan

2018-05-01

Cardiac alternans is a disturbance in heart rhythm that is linked to the onset of lethal cardiac arrhythmias. Mechanical perturbation control has been recently used to suppress alternans in cardiac tissue of relevant size. In this control strategy, cardiac tissue mechanics are perturbed via active tension generated by the heart's electrical activity, which alters the tissue's electric wave profile through mechanoelectric coupling. We analyze the effects of mechanical perturbation on the dynamics of a map model that couples the membrane voltage and active tension systems at the cellular level. Therefore, a two-dimensional iterative map of the heart beat-to-beat dynamics is introduced, and a stability analysis of the system of coupled maps is performed in the presence of a mechanical perturbation algorithm. To this end, a bidirectional coupling between the membrane voltage and active tension systems in a single cardiac cell is provided, and a discrete form of the proposed control algorithm, that can be incorporated in the coupled maps, is derived. In addition, a realistic electromechanical model of cardiac tissue is employed to explore the feasibility of suppressing alternans at cellular and tissue levels. Electrical activity is represented in two detailed ionic models, the Luo-Rudy 1 and the Fox models, while two active contractile tension models, namely a smooth variant of the Nash-Panfilov model and the Niederer-Hunter-Smith model, are used to represent mechanical activity in the heart. The Mooney-Rivlin passive elasticity model is employed to describe passive mechanical behavior of the myocardium.

Brain-Heart Interaction: Cardiac Complications After Stroke.

Science.gov (United States)

Chen, Zhili; Venkat, Poornima; Seyfried, Don; Chopp, Michael; Yan, Tao; Chen, Jieli

2017-08-04

Neurocardiology is an emerging specialty that addresses the interaction between the brain and the heart, that is, the effects of cardiac injury on the brain and the effects of brain injury on the heart. This review article focuses on cardiac dysfunction in the setting of stroke such as ischemic stroke, brain hemorrhage, and subarachnoid hemorrhage. The majority of post-stroke deaths are attributed to neurological damage, and cardiovascular complications are the second leading cause of post-stroke mortality. Accumulating clinical and experimental evidence suggests a causal relationship between brain damage and heart dysfunction. Thus, it is important to determine whether cardiac dysfunction is triggered by stroke, is an unrelated complication, or is the underlying cause of stroke. Stroke-induced cardiac damage may lead to fatality or potentially lifelong cardiac problems (such as heart failure), or to mild and recoverable damage such as neurogenic stress cardiomyopathy and Takotsubo cardiomyopathy. The role of location and lateralization of brain lesions after stroke in brain-heart interaction; clinical biomarkers and manifestations of cardiac complications; and underlying mechanisms of brain-heart interaction after stroke, such as the hypothalamic-pituitary-adrenal axis; catecholamine surge; sympathetic and parasympathetic regulation; microvesicles; microRNAs; gut microbiome, immunoresponse, and systemic inflammation, are discussed. © 2017 American Heart Association, Inc.

Role of cardiac biomarkers (troponin I and CK-MB as predictors of quality of life and long-term outcome after cardiac surgery

Directory of Open Access Journals (Sweden)

Bignami Elena

2009-01-01

Full Text Available Perioperative and postoperative morbidity and mortality associated with cardiac surgery affect both the outcome and quality of life. Markers such as troponin effectively predict short-term outcome. In a prospective cohort study in a University Hospital we assessed the role of cardiac biomarkers, also as predictors of long-term outcome and life quality after cardiac surgery with a three-year follow-up after conventional heart surgery. Patients were interviewed via phone calls with a structured questionnaire examining general health, functional status, activities of daily living, perception of life quality and need for hospital readmission. Descriptive statistics and multivariate analysis were performed. Out of 252 consecutive patients, 8 (3.2% died at the three years follow up: 7 for cardiac complications and 1 for cancer. Thirty-six patients (13.5% had hospital readmission for cardiac causes (mostly for atrial fibrillation or other arrhythmias (9.3%, but none needed cardiac surgical reintervention; 21 patients (7.9% were hospitalised for non-cardiac causes. No limitation in function activities of daily living was reported by most patients (94%, 92% perceived their general health as excellent, very good or good and none considered it insufficient; 80% were NYHA I, 17% NYHA II, 3% NYHA III and none NYHA IV. Multivariate analysis indicated preoperative treatment with digitalis or nitrates, and postoperative cardiac biomarkers release was independently associated to death. Elevated cardiac biomarker release and length of hospital stay were the only postoperative independent predictors of death in this study.

Cardiac MRI of the athlete's heart

NARCIS (Netherlands)

Prakken, N.H.J.

2010-01-01

The increase in pre-participation cardiovascular screening using the Lausanne protocol will ultimately lead to an increased use of cardiac MRI and MDCT in the cardiovascular work-up of athletes. The role of cardiac MRI is well established in the evaluation of cardiomyopathies, myocarditis, aortic

Cardiac norepinephrine kinetics in hypertrophic cardiomyopathy

International Nuclear Information System (INIS)

Brush, J.E. Jr.; Eisenhofer, G.; Garty, M.; Stull, R.; Maron, B.J.; Cannon, R.O. III; Panza, J.A.; Epstein, S.E.; Goldstein, D.S.

1989-01-01

We examined the uptake and release of norepinephrine in the cardiac circulation and other regional vascular beds in 11 patients with hypertrophic cardiomyopathy (HCM) and in 10 control subjects during simultaneous infusion of tracer-labeled norepinephrine and isoproterenol. Cardiac neuronal uptake of norepinephrine was assessed by comparing regional removal of tracer-labeled norepinephrine with that of tracer-labeled isoproterenol (which is not a substrate for neuronal uptake) and by the relation between production of dihydroxyphenylglycol (DHPG), an exclusively intraneuronal metabolite of norepinephrine, and regional spillover of norepinephrine. Cardiac extraction of norepinephrine averaged 59 +/- 17% in the patients with HCM, significantly less than in the control subjects (79 +/- 13%, p less than 0.05), whereas cardiac extraction of isoproterenol was similar in the two groups (13 +/- 23% versus 13 +/- 14%), indicating that neuronal uptake of norepinephrine was decreased in the patients with HCM. The cardiac arteriovenous difference in norepinephrine was significantly larger in the patients with HCM than in the control subjects (73 +/- 77 versus 13 +/- 50 pg/ml, p less than 0.05), as was the product of the arteriovenous difference in norepinephrine and coronary blood flow (7.3 +/- 7.3 versus 0.8 +/- 3.0 ng/min, p less than 0.05)

Biomimetic material strategies for cardiac tissue engineering

International Nuclear Information System (INIS)

Prabhakaran, Molamma P.; Venugopal, J.; Kai, Dan; Ramakrishna, Seeram

2011-01-01

Cardiovascular disease precedes many serious complications including myocardial infarction (MI) and it remains a major problem for the global community. Adult mammalian heart has limited ability to regenerate and compensate for the loss of cardiomyocytes. Restoration of cardiac function by replacement of diseased myocardium with functional cardiomyocytes is an intriguing strategy because it offers a potential cure for MI. Biomaterials are fabricated in nanometer scale dimensions by combining the chemical, biological, mechanical and electrical aspects of material for potential tissue engineering (TE) applications. Synthetic polymers offer advantageous in their ability to tailor the mechanical properties, and natural polymers offer cell recognition sites necessary for cell, adhesion and proliferation. Cardiac tissue engineering (TE) aim for the development of a bioengineered construct that can provide physical support to the damaged cardiac tissue by replacing certain functions of the damaged extracellular matrix and prevent adverse cardiac remodeling and dysfunction after MI. Electrospun nanofibers are applied as heart muscle patches, while hydrogels serve as a platform for controlled delivery of growth factors, prevent mechanical complications and assist in cell recruitment. This article reviews the applications of different natural and synthetic polymeric materials utilized as cardiac patches, injectables or 3D constructs for cardiac TE. Smart organization of nanoscale assemblies with synergistic approaches of utilizing nanofibers and hydrogels could further advance the field of cardiac tissue engineering. Rapid innovations in biomedical engineering and cell biology will bring about new insights in the development of optimal scaffolds and methods to create tissue constructs with relevant contractile properties and electrical integration to replace or substitute the diseased myocardium.

Psychosocial aspects of cardiac rehabilitation in Europe.

Science.gov (United States)

Maes, S

1992-11-01

While the present objectives of cardiac rehabilitation include recovery or restoration of everyday behaviour and secondary prevention, the effects of the traditional exercise-based, cardiac rehabilitation programmes are quite modest. It is argued that psychological interventions may affect these targets more easily, since there is evidence from controlled studies that psychological interventions may have beneficial effects on psychosocial recovery, compliance with medical advice and cardiovascular morbidity and mortality. As a consequence one may expect that psychologists would be at least part-time members of most cardiac rehabilitation teams in European countries. In order to get an impression of the position of psychologists and the share of psychosocial care in cardiac rehabilitation in Europe, a questionnaire was sent out to two or three individuals in each European country. Health care professionals from 16 European countries returned their completed questionnaires on time. Among other things, the results show that in general social workers and psychologists, who may be considered the main potential agents for psychosocial care, are largely underrepresented in cardiac rehabilitation teams. As far as psychologists are concerned, the number involved in cardiac rehabilitation varies significantly from country to country. Three groups of countries could be distinguished: a group consisting of The Netherlands, Austria, and Italy, where psychologists are fairly well represented; a second one consisting of Norway, Finland and Belgium, where small numbers of psychologists are involved in cardiac rehabilitation; and a third group (the largest) consisting of Switzerland, Poland, Czechoslovakia, Denmark, Ireland, Sweden, the UK, Greece, Portugal and Turkey, where the number of psychologists is negligible.

Biomimetic material strategies for cardiac tissue engineering

Energy Technology Data Exchange (ETDEWEB)

Prabhakaran, Molamma P., E-mail: nnimpp@nus.edu.sg [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Venugopal, J. [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore); Kai, Dan [NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore (Singapore); Ramakrishna, Seeram [Health Care and Energy Materials Laboratory, Nanoscience and Nanotechnology Initiative, Faculty of Engineering, National University of Singapore, 2 Engineering Drive 3, Singapore 117576 (Singapore)

2011-04-08

Cardiovascular disease precedes many serious complications including myocardial infarction (MI) and it remains a major problem for the global community. Adult mammalian heart has limited ability to regenerate and compensate for the loss of cardiomyocytes. Restoration of cardiac function by replacement of diseased myocardium with functional cardiomyocytes is an intriguing strategy because it offers a potential cure for MI. Biomaterials are fabricated in nanometer scale dimensions by combining the chemical, biological, mechanical and electrical aspects of material for potential tissue engineering (TE) applications. Synthetic polymers offer advantageous in their ability to tailor the mechanical properties, and natural polymers offer cell recognition sites necessary for cell, adhesion and proliferation. Cardiac tissue engineering (TE) aim for the development of a bioengineered construct that can provide physical support to the damaged cardiac tissue by replacing certain functions of the damaged extracellular matrix and prevent adverse cardiac remodeling and dysfunction after MI. Electrospun nanofibers are applied as heart muscle patches, while hydrogels serve as a platform for controlled delivery of growth factors, prevent mechanical complications and assist in cell recruitment. This article reviews the applications of different natural and synthetic polymeric materials utilized as cardiac patches, injectables or 3D constructs for cardiac TE. Smart organization of nanoscale assemblies with synergistic approaches of utilizing nanofibers and hydrogels could further advance the field of cardiac tissue engineering. Rapid innovations in biomedical engineering and cell biology will bring about new insights in the development of optimal scaffolds and methods to create tissue constructs with relevant contractile properties and electrical integration to replace or substitute the diseased myocardium.

Dual-gated cardiac PET-clinical feasibility study

Energy Technology Data Exchange (ETDEWEB)

Teraes, Mika; Kokki, Tommi; Noponen, Tommi; Hoppela, Erika; Sipilae, Hannu T.; Knuuti, Juhani [Turku PET Centre, PO BOX 52, Turku (Finland); Durand-Schaefer, Nicolas [General Electric Medical Systems, Buc (France); Pietilae, Mikko [Turku University Hospital, Department of Internal Medicine, Turku (Finland); Kiss, Jan [Turku University Hospital, Department of Surgery, Turku (Finland)

2010-03-15

Both respiratory and cardiac motions reduce image quality in myocardial imaging. For accurate imaging of small structures such as vulnerable coronary plaques, simultaneous cardiac and respiratory gating is warranted. This study tests the feasibility of a recently developed robust method for cardiac-respiratory gating. List-mode data with triggers from respiratory and cardiac cycles are rearranged into dual-gated segments and reconstructed with standard algorithms of a commercial PET/CT scanner. Cardiac gates were defined as three fixed phases and one variable diastolic phase. Chest motion was measured with a respiratory gating device and post-processed to determine gates. Preservation of quantification in dual-gated images was tested with an IEC whole-body phantom. Minipig and human studies were performed to evaluate the feasibility of the method. In minipig studies, a coronary catheter with radioactive tip was guided in coronary artery for in vivo and ex vivo acquisitions. Dual gating in humans with suspected cardiac disorders was performed using 18-F-FDG as a tracer. The method was found feasible for in vivo imaging and the radioactive catheter tip was better resolved in gated images. In human studies, the dual gating was found feasible and easy for clinical routine. Maximal movement of myocardial surface in cranio-caudal direction was over 20 mm. The shape of myocardium was clearly different between the gates and papillary muscles become more visible in diastolic images. The first clinical experiences using robust cardiac-respiratory dual gating are encouraging. Further testing in larger clinical populations using tracers designed especially for plaque imaging is warranted. (orig.)

Dual-gated cardiac PET-clinical feasibility study

International Nuclear Information System (INIS)

Teraes, Mika; Kokki, Tommi; Noponen, Tommi; Hoppela, Erika; Sipilae, Hannu T.; Knuuti, Juhani; Durand-Schaefer, Nicolas; Pietilae, Mikko; Kiss, Jan

2010-01-01

Both respiratory and cardiac motions reduce image quality in myocardial imaging. For accurate imaging of small structures such as vulnerable coronary plaques, simultaneous cardiac and respiratory gating is warranted. This study tests the feasibility of a recently developed robust method for cardiac-respiratory gating. List-mode data with triggers from respiratory and cardiac cycles are rearranged into dual-gated segments and reconstructed with standard algorithms of a commercial PET/CT scanner. Cardiac gates were defined as three fixed phases and one variable diastolic phase. Chest motion was measured with a respiratory gating device and post-processed to determine gates. Preservation of quantification in dual-gated images was tested with an IEC whole-body phantom. Minipig and human studies were performed to evaluate the feasibility of the method. In minipig studies, a coronary catheter with radioactive tip was guided in coronary artery for in vivo and ex vivo acquisitions. Dual gating in humans with suspected cardiac disorders was performed using 18-F-FDG as a tracer. The method was found feasible for in vivo imaging and the radioactive catheter tip was better resolved in gated images. In human studies, the dual gating was found feasible and easy for clinical routine. Maximal movement of myocardial surface in cranio-caudal direction was over 20 mm. The shape of myocardium was clearly different between the gates and papillary muscles become more visible in diastolic images. The first clinical experiences using robust cardiac-respiratory dual gating are encouraging. Further testing in larger clinical populations using tracers designed especially for plaque imaging is warranted. (orig.)

Animal models of cardiac cachexia.

Science.gov (United States)

Molinari, Francesca; Malara, Natalia; Mollace, Vincenzo; Rosano, Giuseppe; Ferraro, Elisabetta

2016-09-15

Cachexia is the loss of body weight associated with several chronic diseases including chronic heart failure (CHF). The cachectic condition is mainly due to loss of skeletal muscle mass and adipose tissue depletion. The majority of experimental in vivo studies on cachexia rely on animal models of cancer cachexia while a reliable and appropriate model for cardiac cachexia has not yet been established. A critical issue in generating a cardiac cachexia model is that genetic modifications or pharmacological treatments impairing the heart functionality and used to obtain the heart failure model might likely impair the skeletal muscle, this also being a striated muscle and sharing with the myocardium several molecular and physiological mechanisms. On the other hand, often, the induction of heart damage in the several existing models of heart failure does not necessarily lead to skeletal muscle loss and cachexia. Here we describe the main features of cardiac cachexia and illustrate some animal models proposed for cardiac cachexia studies; they include the genetic calsequestrin and Dahl salt-sensitive models, the monocrotaline model and the surgical models obtained by left anterior descending (LAD) ligation, transverse aortic constriction (TAC) and ascending aortic banding. The availability of a specific animal model for cardiac cachexia is a crucial issue since, besides the common aspects of cachexia in the different syndromes, each disease has some peculiarities in its etiology and pathophysiology leading to cachexia. Such peculiarities need to be unraveled in order to find new targets for effective therapies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Can cardiac surgery cause hypopituitarism?

Science.gov (United States)

Francis, Flverly; Burger, Ines; Poll, Eva Maria; Reineke, Andrea; Strasburger, Christian J; Dohmen, Guido; Gilsbach, Joachim M; Kreitschmann-Andermahr, Ilonka

2012-03-01

Apoplexy of pituitary adenomas with subsequent hypopituitarism is a rare but well recognized complication following cardiac surgery. The nature of cardiac on-pump surgery provides a risk of damage to the pituitary because the vascular supply of the pituitary is not included in the cerebral autoregulation. Thus, pituitary tissue may exhibit an increased susceptibility to hypoperfusion, ischemia or intraoperative embolism. After on-pump procedures, patients often present with physical and psychosocial impairments which resemble symptoms of hypopituitarism. Therefore, we analyzed whether on-pump cardiac surgery may cause pituitary dysfunction also in the absence of pre-existing pituitary disease. Twenty-five patients were examined 3-12 months after on-pump cardiac surgery. Basal hormone levels for all four anterior pituitary hormone axes were measured and a short synacthen test and a growth hormone releasing hormone plus arginine (GHRH-ARG)-test were performed. Quality of life (QoL), depression, subjective distress for a specific life event, sleep quality and fatigue were assessed by means of self-rating questionnaires. Hormonal alterations were only slight and no signs of anterior hypopituitarism were found except for an insufficient growth hormone rise in two overweight patients in the GHRH-ARG-test. Psychosocial impairment was pronounced, including symptoms of moderate to severe depression in 9, reduced mental QoL in 8, dysfunctional coping in 6 and pronounced sleep disturbances in 16 patients. Hormone levels did not correlate with psychosocial impairment. On-pump cardiac surgery did not cause relevant hypopituitarism in our sample of patients and does not serve to explain the psychosocial symptoms of these patients.

Cardiac effects of noncardiac neoplasms

International Nuclear Information System (INIS)

Schoen, F.J.; Berger, B.M.; Guerina, N.G.

1984-01-01

Clinically significant cardiovascular abnormalities may occur as secondary manifestations of noncardiac neoplasms. The principal cardiac effects of noncardiac tumors include the direct results of metastases to the heart or lungs, the indirect effects of circulating tumor products (causing nonbacterial thrombotic endocarditis, myeloma-associated amyloidosis, pheochromocytoma-associated cardiac hypertrophy and myofibrillar degeneration, and carcinoid heart disease), and the undesired cardiotoxicities of chemotherapy and radiotherapy. 89 references

Characterization of mitochondrial injury after cardiac arrest (COMICA).

Science.gov (United States)

Donnino, Michael W; Liu, Xiaowen; Andersen, Lars W; Rittenberger, Jon C; Abella, Benjamin S; Gaieski, David F; Ornato, Joseph P; Gazmuri, Raúl J; Grossestreuer, Anne V; Cocchi, Michael N; Abbate, Antonio; Uber, Amy; Clore, John; Peberdy, Mary Anne; Callaway, Clifton W

2017-04-01

Mitochondrial injury post-cardiac arrest has been described in pre-clinical settings but the extent to which this injury occurs in humans remains largely unknown. We hypothesized that increased levels of mitochondrial biomarkers would be associated with mortality and neurological morbidity in post-cardiac arrest subjects. We performed a prospective multicenter study of post-cardiac arrest subjects. Inclusion criteria were comatose adults who suffered an out-of-hospital cardiac arrest. Mitochondrial biomarkers were measured at 0, 12, 24, 36 and 48h after return of spontaneous circulation as well as in healthy controls. Out of 111 subjects enrolled, 102 had evaluable samples at 0h. Cardiac arrest subjects had higher baseline cytochrome c levels compared to controls (2.18ng/mL [0.74, 7.74] vs. 0.16ng/mL [0.03, 0.91], p<0.001), and subjects who died had higher 0h cytochrome c levels compared to survivors (3.66ng/mL [1.40, 14.9] vs. 1.27ng/mL [0.16, 2.37], p<0.001). There were significantly higher Ribonuclease P (RNaseP) (3.3 [1.2, 5.7] vs. 1.2 [0.8, 1.2], p<0.001) and Beta-2microglobulin (B2M) (12.0 [1.0, 22.9], vs. 0.6 [0.6, 1.3], p<0.001) levels in cardiac arrest subjects at baseline compared to the control subjects. There were no differences between survivors and non-survivors for mitochondrial DNA, nuclear DNA, or cell free DNA. Cytochrome c was increased in post- cardiac arrest subjects compared to controls, and in post-cardiac arrest non-survivors compared to survivors. Nuclear DNA and cell free DNA was increased in plasma of post-cardiac arrest subjects. There were no differences in mitochondrial DNA, nuclear DNA, or cell free DNA between survivors and non-survivors. Mitochondrial injury markers showed mixed results in the post-cardiac arrest period. Future research needs to investigate these differences. Copyright © 2017 Elsevier B.V. All rights reserved.

Korean guidelines for the appropriate use of cardiac CT

Energy Technology Data Exchange (ETDEWEB)

Kim, Young Jin [Dept. of Radiology, Severance Hospital, Yonsei University College of Medicine, Seoul(Korea, Republic of); Yong, Hwan Seok [Dept. of Radiology, Korea University Guro Hospital, Korea University College of Medicine, Seoul(Korea, Republic of); Kim, Sung Mok [Dept. of Radiology, amsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of); Kim, Jung A [Dept. of Radiology, Ilsan Paik Hospital, Inje University College of Medicine, Goyang (Korea, Republic of); Hong, Yoo Jin [Dept. of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul (Korea, Republic of)

2015-04-15

The development of cardiac CT has provided a non-invasive alternative to echocardiography, exercise electrocardiogram, and invasive angiography and cardiac CT continues to develop at an exponential speed even now. The appropriate use of cardiac CT may lead to improvements in the medical performances of physicians and can reduce medical costs which eventually contribute to better public health. However, until now, there has been no guideline regarding the appropriate use of cardiac CT in Korea. We intend to provide guidelines for the appropriate use of cardiac CT in heart diseases based on scientific data. The purpose of this guideline is to assist clinicians and other health professionals in the use of cardiac CT for diagnosis and treatment of heart diseases, especially in patients at high risk or suspected of heart disease.

Air medical transport of cardiac patients.

Science.gov (United States)

Essebag, Vidal; Halabi, Abdul R; Churchill-Smith, Michael; Lutchmedial, Sohrab

2003-11-01

The air medical transport of cardiac patients is a rapidly expanding practice. For various medical, social, and economic indications, patients are being flown longer distances at commercial altitudes, including international and intercontinental flights. There are data supporting the use of short-distance helicopter flights early in the course of a cardiac event for patients needing emergent transfer for percutaneous coronary intervention or aortocoronary bypass. When considering elective long-distance air medical transport of cardiac patients for social or economic reasons, it is necessary to weigh the benefits against the potential risks of flight. A few recent studies suggest that long-distance air medical transport is safe under certain circumstances. Current guidelines for air travel after myocardial infarction do not address the use of medical escorts or air ambulances equipped with intensive care facilities. Further research using larger prospective studies is needed to better define criteria for safe long-distance air medical transport of cardiac patients.

Programmatic blood conservation in cardiac surgery.

Science.gov (United States)

Ralley, Fiona E

2007-12-01

Despite efforts to reduce blood transfusion rates in cardiac surgery over the past 40 years, cardiac surgery still consumes 10% to 20% of the blood transfused in the United States. This large demand has not only placed a significant pressure on the national blood supply, resulting in frequent shortages, but also has lead to many technical and pharmacological advances in blood conservation strategies in recent years. Recently, studies have shown that an organized approach to blood conservation in cardiac surgery is effective in significantly reducing the perioperative use of allogeneic blood and blood products. However, blood conservation techniques are multiple, varied, and in many situations costly and thus cannot be uniformly applied to all patients. Early preoperative planning and a coordinated perioperative plan allow the appropriate use of blood conservation modalities to ensure that their benefits span the entire perioperative period. This article describes some of the modalities currently used in patients undergoing cardiac surgery.

Cardiac tissue engineering

Directory of Open Access Journals (Sweden)

MILICA RADISIC

2005-03-01

Full Text Available We hypothesized that clinically sized (1-5 mm thick,compact cardiac constructs containing physiologically high density of viable cells (~108 cells/cm3 can be engineered in vitro by using biomimetic culture systems capable of providing oxygen transport and electrical stimulation, designed to mimic those in native heart. This hypothesis was tested by culturing rat heart cells on polymer scaffolds, either with perfusion of culture medium (physiologic interstitial velocity, supplementation of perfluorocarbons, or with electrical stimulation (continuous application of biphasic pulses, 2 ms, 5 V, 1 Hz. Tissue constructs cultured without perfusion or electrical stimulation served as controls. Medium perfusion and addition of perfluorocarbons resulted in compact, thick constructs containing physiologic density of viable, electromechanically coupled cells, in contrast to control constructs which had only a ~100 mm thick peripheral region with functionally connected cells. Electrical stimulation of cultured constructs resulted in markedly improved contractile properties, increased amounts of cardiac proteins, and remarkably well developed ultrastructure (similar to that of native heart as compared to non-stimulated controls. We discuss here the state of the art of cardiac tissue engineering, in light of the biomimetic approach that reproduces in vitro some of the conditions present during normal tissue development.

Cerebral Oximetry in Cardiac Surgery

Directory of Open Access Journals (Sweden)

A. N. Shepelyuk

2012-01-01

Full Text Available Based on the data of numerous current references, the review describes different neuromonitoring methods during cardiac surgery under extracorporeal circulation. It shows that it is important and necessary to make neuromonitoring for the early diagnosis and prevention of neurological complications after cardiac surgery. Particular attention is given to cerebral oximetry; the possibilities and advantages of this technique are described. Correction of cerebral oximetric values is shown to improve survival rates and to reduce the incidence of postoperative complications. Lack of cerebral oximetry monitoring denudes a clinician of important information and possibilities to optimize patient status and to prevent potentially menacing complications, which allows one to conclude that it is necessary to use cerebral oximetry procedures within neu-romonitoring in cardiac surgery. Key words: extracorporeal circulation, cerebral oximetry, neurological dysfunction, cerebral oxygenation.

A Puzzle Used to Teach the Cardiac Cycle

Science.gov (United States)

Marcondes, Fernanda K.; Moura, Maria J. C. S.; Sanches, Andrea; Costa, Rafaela; Oliveira de Lima, Patricia; Groppo, Francisco Carlos; Amaral, Maria E. C.; Zeni, Paula; Gaviao, Kelly Cristina; Montrezor, Luís H.

2015-01-01

The aim of the present article is to describe a puzzle developed for use in teaching cardiac physiology classes. The puzzle presents figures of phases of the cardiac cycle and a table with five columns: phases of cardiac cycle, atrial state, ventricular state, state of atrioventricular valves, and pulmonary and aortic valves. Chips are provided…

Salacia oblonga root improves cardiac lipid metabolism in Zucker diabetic fatty rats: Modulation of cardiac PPAR-α-mediated transcription of fatty acid metabolic genes

International Nuclear Information System (INIS)

Huang, Tom H.-W.; Yang Qinglin; Harada, Masaki; Uberai, Jasna; Radford, Jane; Li, George Q.; Yamahara, Johji; Roufogalis, Basil D.; Li Yuhao

2006-01-01

Excess cardiac triglyceride accumulation in diabetes and obesity induces lipotoxicity, which predisposes the myocytes to death. On the other hand, increased cardiac fatty acid (FA) oxidation plays a role in the development of myocardial dysfunction in diabetes. PPAR-α plays an important role in maintaining homeostasis of lipid metabolism. We have previously demonstrated that the extract from Salacia oblonga root (SOE), an Ayurvedic anti-diabetic and anti-obesity medicine, improves hyperlipidemia in Zucker diabetic fatty (ZDF) rats (a genetic model of type 2 diabetes and obesity) and possesses PPAR-α activating properties. Here we demonstrate that chronic oral administration of SOE reduces cardiac triglyceride and FA contents and decreases the Oil red O-stained area in the myocardium of ZDF rats, which parallels the effects on plasma triglyceride and FA levels. Furthermore, the treatment suppressed cardiac overexpression of both FA transporter protein-1 mRNA and protein in ZDF rats, suggesting inhibition of increased cardiac FA uptake as the basis for decreased cardiac FA levels. Additionally, the treatment also inhibited overexpression in ZDF rat heart of PPAR-α mRNA and protein and carnitine palmitoyltransferase-1, acyl-CoA oxidase and 5'-AMP-activated protein kinase mRNAs and restored the downregulated acetyl-CoA carboxylase mRNA. These results suggest that SOE inhibits cardiac FA oxidation in ZDF rats. Thus, our findings suggest that improvement by SOE of excess cardiac lipid accumulation and increased cardiac FA oxidation in diabetes and obesity occurs by reduction of cardiac FA uptake, thereby modulating cardiac PPAR-α-mediated FA metabolic gene transcription

Short-term exercise worsens cardiac oxidative stress and fibrosis in 8-month-old db/db mice by depleting cardiac glutathione.

Science.gov (United States)

Laher, Ismail; Beam, Julianne; Botta, Amy; Barendregt, Rebekah; Sulistyoningrum, Dian; Devlin, Angela; Rheault, Mark; Ghosh, Sanjoy

2013-01-01

Moderate exercise improves cardiac antioxidant status in young humans and animals with Type-2 diabetes (T2D). Given that both diabetes and advancing age synergistically decrease antioxidant expression in most tissues, it is unclear whether exercise can upregulate cardiac antioxidants in chronic animal models of T2D. To this end, 8-month-old T2D and normoglycemic mice were exercised for 3 weeks, and cardiac redox status was evaluated. As expected, moderate exercise increased cardiac antioxidants and attenuated oxidative damage in normoglycemic mice. In contrast, similar exercise protocol in 8-month-old db/db mice worsened cardiac oxidative damage, which was associated with a specific dysregulation of glutathione (GSH) homeostasis. Expression of enzymes for GSH biosynthesis [γ-glutamylcysteine synthase, glutathione reductase] as well as for GSH-mediated detoxification (glutathione peroxidase, glutathione-S-transferase) was lower, while toxic metabolites dependent on GSH for clearance (4-hydroxynonenal) were increased in exercised diabetic mice hearts. To validate GSH loss as an important factor for such aggravated damage, daily administration of GSH restored cardiac GSH levels in exercised diabetic mice. Such supplementation attenuated both oxidative damage and fibrotic changes in the myocardium. Expression of transforming growth factor beta (TGF-β) and its regulated genes which are responsible for such profibrotic changes were also attenuated with GSH supplementation. These novel findings in a long-term T2D animal model demonstrate that short-term exercise by itself can deplete cardiac GSH and aggravate cardiac oxidative stress. As GSH administration conferred protection in 8-month-old diabetic mice undergoing exercise, supplementation with GSH-enhancing agents may be beneficial in elderly diabetic patients undergoing exercise.

Ventilation and gas exchange management after cardiac arrest.

Science.gov (United States)

Sutherasan, Yuda; Raimondo, Pasquale; Pelosi, Paolo

2015-12-01

For several decades, physicians had integrated several interventions aiming to improve the outcomes in post-cardiac arrest patients. However, the mortality rate after cardiac arrest is still as high as 50%. Post-cardiac arrest syndrome is associated with high morbidity and mortality due to not only poor neurological outcome and cardiovascular failure but also respiratory dysfunction. To minimize ventilator-associated lung injury, protective mechanical ventilation by using low tidal volume ventilation and driving pressure may decrease pulmonary complications and improve survival. Low level of positive end-expiratory pressure (PEEP) can be initiated and titrated with careful cardiac output and respiratory mechanics monitoring. Furthermore, optimizing gas exchange by avoiding hypoxia and hyperoxia as well as maintaining normocarbia may improve neurological and survival outcome. Early multidisciplinary cardiac rehabilitation intervention is recommended. Minimally invasive monitoring techniques, that is, echocardiography, transpulmonary thermodilution method measuring extravascular lung water, as well as transcranial Doppler ultrasound, might be useful to improve appropriate management of post-cardiac arrest patients. Copyright © 2015 Elsevier Ltd. All rights reserved.

Pharmacological targeting of CDK9 in cardiac hypertrophy.

Science.gov (United States)

Krystof, Vladimír; Chamrád, Ivo; Jorda, Radek; Kohoutek, Jirí

2010-07-01

Cardiac hypertrophy allows the heart to adapt to workload, but persistent or unphysiological stimulus can result in pump failure. Cardiac hypertrophy is characterized by an increase in the size of differentiated cardiac myocytes. At the molecular level, growth of cells is linked to intensive transcription and translation. Several cyclin-dependent kinases (CDKs) have been identified as principal regulators of transcription, and among these CDK9 is directly associated with cardiac hypertrophy. CDK9 phosphorylates the C-terminal domain of RNA polymerase II and thus stimulates the elongation phase of transcription. Chronic activation of CDK9 causes not only cardiac myocyte enlargement but also confers predisposition to heart failure. Due to the long interest of molecular oncologists and medicinal chemists in CDKs as potential targets of anticancer drugs, a portfolio of small-molecule inhibitors of CDK9 is available. Recent determination of CDK9's crystal structure now allows the development of selective inhibitors and their further optimization in terms of biochemical potency and selectivity. CDK9 may therefore constitute a novel target for drugs against cardiac hypertrophy.

Titanium dioxide nanoparticle-induced dysfunction of cardiac hemodynamics is involved in cardiac inflammation in mice.

Science.gov (United States)

Hong, Fashui; Wu, Nan; Zhao, Xiangyu; Tian, Yusheng; Zhou, Yingjun; Chen, Ting; Zhai, Yanyu; Ji, Li

2016-12-01

In the past two decades, titanium dioxide nanoparticles (TiO 2 NPs) have been extensively used in medicine, food industry and other daily life, while their possible interactions with the their influence and human body on human health remain not well understood. Thus, the study was designed to examine whether long-term exposure to TiO 2 NPs cause myocardial dysfunction which is involved in cardiac lesions and alter expression of genes and proteins involving inflammatory response in the mouse heart. The findings showed that intragastric feeding for nine consecutive months with TiO 2 NPs resulted in titanium accumulation, infiltration of inflammatory cells and apoptosis of heart, reductions in net increases of body weight, cardiac indices of function (LV systolic pressure, maximal rate of pressure increase over time, maximal rate of pressure decrease over time and coronary flow), and increases in heart indices, cardiac indices of function (LV end-diastolic pressure and heart rate) in mice. TiO 2 NPs also decreased ATP production in the hearts. Furthermore, TiO 2 NPs increased expression of nuclear factor-κB, interleukin-lβ and tumour necrosis factor-α, and reduced expression of anti-inflammatory cytokines including suppressor of cytokine signaling (SOCS) 1 and SOCS3 in the cardiac tissue. These results suggest that TiO 2 NPs may modulate the cardiac function and expression of inflammatory cytokines. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2917-2927, 2016. © 2016 Wiley Periodicals, Inc.

Biomarkers for cardiac cachexia: reality or utopia.

Science.gov (United States)

Martins, Telma; Vitorino, Rui; Amado, Francisco; Duarte, José Alberto; Ferreira, Rita

2014-09-25

Cardiac cachexia is a serious complication of chronic heart failure, characterized by significant weight loss and body wasting. Chronic heart failure-related muscle wasting results from a chronic imbalance in the activation of anabolic or catabolic pathways, caused by a series of immunological, metabolic, and neurohormonal processes. In spite of the high morbidity and mortality associated to this condition, there is no universally accepted definition or specific biomarkers for cardiac cachexia, which makes its diagnosis and treatment difficult. Several hormonal, inflammatory and oxidative stress molecules have been proposed as serological markers of prognosis in cardiac cachexia but with doubtful success. As individual biomarkers may have limited sensitivity and specificity, multimarker strategies involving mediators of the biological processes modulated by cardiac cachexia will strongly contribute for the diagnosis and management of the disease, as well as for the establishment of new therapeutic targets. An integrated analysis of the biomarkers proposed so far for cardiac cachexia is made in the present review, highlighting the biological processes to which they are related. Copyright © 2014 Elsevier B.V. All rights reserved.

Practical textbook of cardiac CT and MRI

Energy Technology Data Exchange (ETDEWEB)

Lim, Tae-Hwan (ed.) [ASAN Medical Center, Seoul (Korea, Republic of). Dept. of Radiology

2015-04-01

Guide to the interpretation of cardiac CT and MRI for the purposes of diagnosis, treatment planning, and follow-up. Emphasis on applications in a wide range of real clinical situations. Numerous informative illustrations. Summarizing sections permitting rapid retrieval of information. QR codes allowing access to references, additional figures, and motion pictures from the internet. This up-to-date textbook comprehensively reviews all aspects of cardiac CT and MRI and demonstrates the value of these techniques in clinical practice. A wide range of applications are considered, including imaging of atherosclerotic and non-atherosclerotic coronary artery disease, coronary revascularization, ischemic heart disease, non-ischemic cardiomyopathy, valvular heart disease, cardiac tumors, and pericardial disease. The numerous high-quality images illustrate how to interpret cardiac CT and MRI correctly for the purposes of diagnosis, treatment planning, and follow-up. Helpful summarizing sections in every chapter will facilitate rapid retrieval of information. This book will be of great value to radiologists and cardiologists seeking a reliable guide to the optimal use of cardiac CT and MRI in real clinical situations.

Practical textbook of cardiac CT and MRI

International Nuclear Information System (INIS)

Lim, Tae-Hwan

2015-01-01

Guide to the interpretation of cardiac CT and MRI for the purposes of diagnosis, treatment planning, and follow-up. Emphasis on applications in a wide range of real clinical situations. Numerous informative illustrations. Summarizing sections permitting rapid retrieval of information. QR codes allowing access to references, additional figures, and motion pictures from the internet. This up-to-date textbook comprehensively reviews all aspects of cardiac CT and MRI and demonstrates the value of these techniques in clinical practice. A wide range of applications are considered, including imaging of atherosclerotic and non-atherosclerotic coronary artery disease, coronary revascularization, ischemic heart disease, non-ischemic cardiomyopathy, valvular heart disease, cardiac tumors, and pericardial disease. The numerous high-quality images illustrate how to interpret cardiac CT and MRI correctly for the purposes of diagnosis, treatment planning, and follow-up. Helpful summarizing sections in every chapter will facilitate rapid retrieval of information. This book will be of great value to radiologists and cardiologists seeking a reliable guide to the optimal use of cardiac CT and MRI in real clinical situations.

Cardiac surgery in the Pacific Islands.

Science.gov (United States)

Davis, Philip John; Wainer, Zoe; O'Keefe, Michael; Nand, Parma

2011-12-01

Rheumatic heart disease constitutes a significant disease burden in under-resourced communities. Recognition of the devastating impact of rheumatic heart disease has resulted in volunteer cardiac teams from Australasia providing surgical services to regions of need. The primary objective of this study was to compare New Zealand hospitals' volunteer cardiac surgical operative results in Samoa and Fiji with the accepted surgical mortality and morbidity rates for Australasia. A retrospective review from seven volunteer cardiac surgical trips to Samoa and Fiji from 2003 to 2009 was conducted. Patient data were retrospectively and prospectively collected. Preoperative morbidity and mortality risk were calculated using the European System for Cardiac Operative Risk Evaluation (euroSCORE). Audit data were collated in line with the Australasian Society of Cardiac and Thoracic Surgeons guidelines. One hundred and three operations were performed over 6 years. EuroSCORE predicted an operative mortality of 3.32%. In-hospital mortality was 0.97% and post-discharge mortality was 2.91%, resulting in a 30-day mortality of 3.88%. This study demonstrated that performing cardiac surgery in Fiji and Samoa is viable and safe. However, the mortality was slightly higher than predicted by euroSCORE. Difficulties exist in predicting mortality rates in patients with rheumatic heart disease from Pacific Island nations as known risk scoring models fail to be disease, ethnically or culturally inclusive. Audit processes and risk model development and assessment are an essential part of this complex surgical charity work and will result in improved patient selection and outcomes. © 2011 The Authors. ANZ Journal of Surgery © 2011 Royal Australasian College of Surgeons.

Proteomic analysis reveals new cardiac-specific dystrophin-associated proteins.

Directory of Open Access Journals (Sweden)

Eric K Johnson

Full Text Available Mutations affecting the expression of dystrophin result in progressive loss of skeletal muscle function and cardiomyopathy leading to early mortality. Interestingly, clinical studies revealed no correlation in disease severity or age of onset between cardiac and skeletal muscles, suggesting that dystrophin may play overlapping yet different roles in these two striated muscles. Since dystrophin serves as a structural and signaling scaffold, functional differences likely arise from tissue-specific protein interactions. To test this, we optimized a proteomics-based approach to purify, identify and compare the interactome of dystrophin between cardiac and skeletal muscles from as little as 50 mg of starting material. We found selective tissue-specific differences in the protein associations of cardiac and skeletal muscle full length dystrophin to syntrophins and dystrobrevins that couple dystrophin to signaling pathways. Importantly, we identified novel cardiac-specific interactions of dystrophin with proteins known to regulate cardiac contraction and to be involved in cardiac disease. Our approach overcomes a major challenge in the muscular dystrophy field of rapidly and consistently identifying bona fide dystrophin-interacting proteins in tissues. In addition, our findings support the existence of cardiac-specific functions of dystrophin and may guide studies into early triggers of cardiac disease in Duchenne and Becker muscular dystrophies.

Efficient Isolation of Cardiac Stem Cells from Brown Adipose

Directory of Open Access Journals (Sweden)

Zhiqiang Liu

2010-01-01

Full Text Available Cardiac stem cells represent a logical cell type to exploit in cardiac regeneration. The efficient harvest of cardiac stem cells from a suitable source would turn promising in cardiac stem cell therapy. Brown adipose was recently found to be a new source of cardiac stem cells, instrumental to myocardial regeneration. Unfortunately, an efficient method for the cell isolation is unavailable so far. In our study we have developed a new method for the efficient isolation of cardiac stem cells from brown adipose by combining different enzymes. Results showed that the total cell yield dramatically increased (more than 10 times, P<.01 compared with that by previous method. The content of CD133-positive cells (reported to differentiate into cardiomyocytes with a high frequency was much higher than that in the previous report (22.43% versus 3.5%. Moreover, the isolated cells could be the efficiently differentiated into functional cardiomyocytes in optimized conditions. Thus, the new method we established would be of great use in further exploring cardiac stem cell therapy.

Cardiac Delayed Rectifier Potassium Channels in Health and Disease

Science.gov (United States)

Chen, Lei; Sampson, Kevin J.; Kass, Robert S.

2016-01-01

Cardiac delayed rectifier potassium channels conduct outward potassium currents during the plateau phase of action potentials and play pivotal roles in cardiac repolarization. These include IKs, IKr and the atrial specific IKur channels. In this chapter, we will review the molecular identities and biophysical properties of these channels. Mutations in the genes encoding delayed rectifiers lead to loss- or gain-of-function phenotypes, disrupt normal cardiac repolarization and result in various cardiac rhythm disorders, including congenital Long QT Syndrome, Short QT Syndrome and familial atrial fibrillation. We will also discuss the possibility and prospect of using delayed rectifier channels as therapeutic targets to manage cardiac arrhythmia. PMID:27261823

Ischemic Stroke Due to Cardiac Involvement: Emery Dreifuss Patient

Directory of Open Access Journals (Sweden)

Ersin Kasım Ulusoy

2015-08-01

Full Text Available Emery-Dreifuss muscular dystrophy (EDMD is a hereditary disease. It is characterized by early-onset contractures, slowly progressive weakness, fatigue related to skapulo-humero-peroneal muscle weakness, cardiomyopathy which develops in adulthood and cardiac conduction system block. Cardiac involvement has a prognostic significance in patients with EDMD and even sudden cardiac death may be the first clinical presentation. In this article, an EDMD patient with ischemic stroke clinic who didn’t have regular cardiac follow-up was reported and the importance of the treatment of cardiac diseases which could play a role in ischemic stroke etiology and the implantation of pace-maker was mentioned.

Cardiac Delayed Rectifier Potassium Channels in Health and Disease.

Science.gov (United States)

Chen, Lei; Sampson, Kevin J; Kass, Robert S

2016-06-01

Cardiac delayed rectifier potassium channels conduct outward potassium currents during the plateau phase of action potentials and play pivotal roles in cardiac repolarization. These include IKs, IKr and the atrial specific IKur channels. In this article, we will review their molecular identities and biophysical properties. Mutations in the genes encoding delayed rectifiers lead to loss- or gain-of-function phenotypes, disrupt normal cardiac repolarization and result in various cardiac rhythm disorders, including congenital Long QT Syndrome, Short QT Syndrome and familial atrial fibrillation. We will also discuss the prospect of using delayed rectifier channels as therapeutic targets to manage cardiac arrhythmia. Copyright © 2016 Elsevier Inc. All rights reserved.

Wnt/β-Catenin Signaling during Cardiac Development and Repair

Directory of Open Access Journals (Sweden)

Jan W. Buikema

2014-05-01

Full Text Available Active Wnt/β-catenin signaling is essential for proper cardiac specification, progenitor expansion and myocardial growth. During development, the mass of the embryonic heart increases multiple times to achieve the dimensions of adult ventricular chambers. Cell division in the embryonic heart is fairly present, whereas cell turnover in the adult myocardium is extremely low. Understanding of embryonic cardiomyocyte cell-replication, therefore, could improve strategies for cardiac regenerative therapeutics. Here, we review which role Wnt signaling plays in cardiac development and highlight a selection of attempts that have been made to modulate Wnt signaling after cardiac ischemic injury to improve cardiac function and reduce infarct size.

[Cardiac rehabilitation: current status and future challenges].

Science.gov (United States)

Hahmann, H W

2012-02-01

The goal of cardiac rehabilitation is to support heart patients using a multidisciplinary team in order to obtain the best possible physical and mental health and achieve long-term social reintegration. In addition to improving physical fitness, cardiac rehabilitation restores self-confidence, thus better equipping patients to deal with mental illness and improving their social reintegration ("participation"). Once the causes of disease have been identified and treated as effectively as possible, drug and lifestyle changes form the focus of cardiac rehabilitation measures. In particular diseases, rehabilitation offers the opportunity for targeted educational courses for diabetics or drug dose escalation, as well as special training for heart failure patients. A nationwide network of outpatient heart groups is available for targeted follow-up. Cardiac patients predominantly rehabilitated in follow-up rehabilitation are older and have greater morbidity than in the past; moreover, they generally come out of acute clinical care earlier and are discharged from hospital more quickly. The proportion of severely ill and multimorbid patients presents a diagnostic and therapeutic challenge in cardiac rehabilitation, although cardiac rehabilitation was not initially conceived for this patient group. The benefit of cardiac rehabilitation has been a well documented reduction in morbidity and mortality. However, hurdles remain, partly due to the patients themselves, partly due to the health insurers. Some insurance providers still refuse rehabilitation for non-ST-segment elevation infarction. In principle rehabilitation can be carried out in an inpatient or an outpatient setting. Specific allocation criteria have not yet been established, but the structure and process quality of outpatient rehabilitation should correspond to that of the inpatient setting. The choice between the two settings should be based on pragmatic criteria. Both settings should be possible for an individual

Complications after cardiac implantable electronic device implantations

DEFF Research Database (Denmark)

Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard

2013-01-01

Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

Molecular nuclear cardiac imaging

Energy Technology Data Exchange (ETDEWEB)

Lee, Dong Soo; Paeng, Jin Chul [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

2004-04-01

Molecular nuclear cardiac imaging has included Tc-99m Annexin imaging to visualize myocardial apoptosis, but is now usually associated with gene therapy and cell-based therapy. Cardiac gene therapy was not successful so far but cardiac reporter gene imaging was made possible using HSV-TK (herpes simplex virus thymidine kinase) and F-18 FHBG (fluoro-hydroxymethylbutyl guanine) or I-124 FIAU (fluoro-deoxyiodo-arabino-furanosyluracil). Gene delivery was performed by needle injection with or without catheter guidance. TK expression did not last longer than 2 weeks in myocardium. Cell-based therapy of ischemic heart or failing heart looks promising, but biodistribution and differentiation of transplanted cells are not known. Reporter genes can be transfected to the stem/progenitor cells and cells containing these genes can be transplanted to the recipients using catheter-based purging or injection. Repeated imaging should be available and if promoter are varied to let express reporter transgenes, cellular (trans)differentiation can be studied. NIS (sodium iodide symporter) or D2R receptor genes are promising in this aspect.

Molecular nuclear cardiac imaging

International Nuclear Information System (INIS)

Lee, Dong Soo; Paeng, Jin Chul

2004-01-01

Molecular nuclear cardiac imaging has included Tc-99m Annexin imaging to visualize myocardial apoptosis, but is now usually associated with gene therapy and cell-based therapy. Cardiac gene therapy was not successful so far but cardiac reporter gene imaging was made possible using HSV-TK (herpes simplex virus thymidine kinase) and F-18 FHBG (fluoro-hydroxymethylbutyl guanine) or I-124 FIAU (fluoro-deoxyiodo-arabino-furanosyluracil). Gene delivery was performed by needle injection with or without catheter guidance. TK expression did not last longer than 2 weeks in myocardium. Cell-based therapy of ischemic heart or failing heart looks promising, but biodistribution and differentiation of transplanted cells are not known. Reporter genes can be transfected to the stem/progenitor cells and cells containing these genes can be transplanted to the recipients using catheter-based purging or injection. Repeated imaging should be available and if promoter are varied to let express reporter transgenes, cellular (trans)differentiation can be studied. NIS (sodium iodide symporter) or D2R receptor genes are promising in this aspect

Succinct history of Greek cardiac surgery.

Science.gov (United States)

Apostolakis, Efstratios; Koletsis, Efstratios; Dougenis, Dimitrios

2008-01-01

The development and evolution of Greek Cardiac Surgery (GCS) has followed the international cardiothoracic surgery after the invention of cardiopulmonary bypass machine by John Gibbon in 1953. Chronologically, the development of GCS could be divided in four periods: (a) the first or essay period (1950-1960) characterized by the lack of organization, the experimentation and hesitation from the surgeons' side, and the reluctance from the patients' side to have an operation in Greece. (b) The second or stabilization period (1960-1970) is the period during which several separate cardiovascular departments were organized and performed the first valve replacement in 1964. (c) The third or "strengthening" period (1970-1985), during which Greek surgeons were trained abroad and adopted new methods and techniques of surgical therapy. The first operations of coronary artery bypass grafting and aortic aneurysm were performed (1973-1975). Various purely Cardiothoracic Centers were founded in Athens and Thessalonica and cardiac surgery became a routine operation. However, these centers were numerically not enough to cover the demand of patients in need of cardiac surgery. (d) The fourth or maturity period (1985 till today). It is characterized by the creation of private cardiac surgery departments and the gradual establishment of new university centers at the periphery, which along with the Onassis Cardiac Center, eliminated any need for patients to leave the country.

Milrinone and esmolol decrease cardiac damage after resuscitation from prolonged cardiac arrest.

Science.gov (United States)

Zoerner, F; Lennmyr, F; Wiklund, L; Martijn, C; Semenas, E

2015-04-01

Long-term survival after cardiac arrest (CA) due to shock-refractory ventricular fibrillation (VF) is low. Clearly, there is a need for new pharmacological interventions in the setting of cardiopulmonary resuscitation (CPR) to improve outcome. Here, hemodynamic parameters and cardiac damage are compared between the treatment group (milrinone, esmolol and vasopressin) and controls (vasopressin only) during resuscitation from prolonged CA in piglets. A total of 26 immature male piglets were subjected to 12-min VF followed by 8-min CPR. The treatment group (n=13) received i.v. (intravenous) boluses vasopressin 0.4 U/kg, esmolol 250 μg/kg and milrinone 25 μg/kg after 13 min, followed by i.v. boluses esmolol 375 μg/kg and milrinone 25 μg/kg after 18 min and continuous esmolol 15 μg/kg/h infusion during 180 min reperfusion, whereas controls (n=13) received equal amounts of vasopressin and saline. A 200 J monophasic counter-shock was delivered to achieve resumption of spontaneous circulation (ROSC) after 8 min CPR. If ROSC was not achieved, another 200 J defibrillation and bolus vasopressin 0.4 U/kg would be administered in both groups. Direct current shocks at 360 J were applied as one shot per minute over maximally 5 min. Hemodynamic variables and troponin I as a marker of cardiac injury were recorded. Troponin I levels after 180 min reperfusion were lower in the treatment group than in controls (Pmilrinone, esmolol and vasopressin decreased cardiac injury compared with vasopressin alone. © 2015 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

Stress cardiac magnetic resonance imaging provides effective cardiac risk reclassification in patients with known or suspected stable coronary artery disease.

Science.gov (United States)

Shah, Ravi; Heydari, Bobak; Coelho-Filho, Otavio; Murthy, Venkatesh L; Abbasi, Siddique; Feng, Jiazhuo H; Pencina, Michael; Neilan, Tomas G; Meadows, Judith L; Francis, Sanjeev; Blankstein, Ron; Steigner, Michael; di Carli, Marcelo; Jerosch-Herold, Michael; Kwong, Raymond Y

2013-08-06

A recent large-scale clinical trial found that an initial invasive strategy does not improve cardiac outcomes beyond optimized medical therapy in patients with stable coronary artery disease. Novel methods to stratify at-risk patients may refine therapeutic decisions to improve outcomes. In a cohort of 815 consecutive patients referred for evaluation of myocardial ischemia, we determined the net reclassification improvement of the risk of cardiac death or nonfatal myocardial infarction (major adverse cardiac events) incremental to clinical risk models, using guideline-based low (3%) annual risk categories. In the whole cohort, inducible ischemia demonstrated a strong association with major adverse cardiac events (hazard ratio=14.66; Pstatistic, 0.81-0.86; P=0.04; adjusted hazard ratio=7.37; PStress cardiac magnetic resonance imaging effectively reclassifies patient risk beyond standard clinical variables, specifically in patients at moderate to high pretest clinical risk and in patients with previous coronary artery disease. http://www.clinicaltrials.gov. Unique identifier: NCT01821924.

Cardiac function studies

International Nuclear Information System (INIS)

Horn, H.J.

1986-01-01

A total of 27 patients were subjected tointramyocardial sequential scintiscanning (first pass) using 99m-Tc human serum albumin. A refined method is described that is suitable to analyse clinically relevant parameters like blood volume, cardiac output, ejection fraction, stroke volume, enddiastolic and endsystolic volumes as well as pulmonal transition time and uses a complete camaracomputer system adapted to the requirements of a routine procedure. Unless there is special hardware available, the method does not yet appear mature enough to be put into general practice. Its importance recently appeared in a new light due to the advent of particularly shortlived isotopes. For the time being, however, ECG-triggered equilibrium studies are to be preferred for cardiac function tests. (TRV) [de

Out-of-hospital cardiac arrest

DEFF Research Database (Denmark)

Sondergaard, Kathrine B; Hansen, Steen Moller; Pallisgaard, Jannik L

2018-01-01

AIMS: Despite wide dissemination of automated external defibrillators (AEDs), bystander defibrillation rates remain low. We aimed to investigate how route distance to the nearest accessible AED was associated with probability of bystander defibrillation in public and residential locations. METHODS......: We used data from the nationwide Danish Cardiac Arrest Registry and the Danish AED Network to identify out-of-hospital cardiac arrests and route distances to nearest accessible registered AED during 2008-2013. The association between route distance and bystander defibrillation was described using...... in public locations, the probability of bystander defibrillation at 0, 100 and 200meters from the nearest AED was 35.7% (95% confidence interval 28.0%-43.5%), 21.3% (95% confidence interval 17.4%-25.2%), and 13.7% (95% confidence interval 10.1%-16.8%), respectively. The corresponding numbers for cardiac...

Comparing Methods for Cardiac Output

DEFF Research Database (Denmark)

Graeser, Karin; Zemtsovski, Mikhail; Kofoed, Klaus F

2018-01-01

of the left ventricular outflow tract. METHODS: The primary aim was a systematic comparison of CO with Doppler-derived 3D TEE and CO by thermodilution in a broad population of patients undergoing cardiac surgery. A subanalysis was performed comparing cross-sectional area by TEE with cardiac computed...... tomography (CT) angiography. Sixty-two patients, scheduled for elective heart surgery, were included; 1 was subsequently excluded for logistic reasons. Inclusion criteria were coronary artery bypass surgery (N = 42) and aortic valve replacement (N = 19). Exclusion criteria were chronic atrial fibrillation......, left ventricular ejection fraction below 0.40 and intracardiac shunts. Nineteen randomly selected patients had a cardiac CT the day before surgery. All images were stored for blinded post hoc analyses, and Bland-Altman plots were used to assess agreement between measurement methods, defined as the bias...

Cardiac arrhythmia as initial presentation of aneurysmal subarachnoid hemorrhage

NARCIS (Netherlands)

van der Kleij, FGH; Henselmans, JML; van de Loosdrecht, AA

1999-01-01

Cardiac arrhythmia and sudden death are most frequently caused by preexisting heart disease. Rarely, cardiac arrhythmia is a first symptom of an acute neurological event. We describe a patient with asystole and other cardiac arrhythmias, as initial symptoms of acute aneurysmal subarachnoid

Cardiac Myosin Binding Protein-C Autoantibodies are Potential Early Indicators of Cardiac Dysfunction and Patient Outcome in Acute Coronary Syndrome.

Science.gov (United States)

Lynch, Thomas L; Kuster, Diederik W D; Gonzalez, Beverly; Balasubramanian, Neelam; Nair, Nandini; Day, Sharlene; Calvino, Jenna E; Tan, Yanli; Liebetrau, Christoph; Troidl, Christian; Hamm, Christian W; Güçlü, Ahmet; McDonough, Barbara; Marian, Ali J; van der Velden, Jolanda; Seidman, Christine E; Huggins, Gordon S; Sadayappan, Sakthivel

2017-04-01

The degradation and release of cardiac myosin binding protein-C (cMyBP-C) upon cardiac damage may stimulate an inflammatory response and autoantibody (AAb) production. We determined whether the presence of cMyBP-C-AAbs associated with adverse cardiac function in CVD patients. Importantly, cMyBP-C-AAbs were significantly detected in ACS patient sera upon arrival to the emergency department, particularly in STEMI patients. Patients positive for cMyBP-C-AAbs had a reduced LVEF and elevated levels of clinical biomarkers of MI. We conclude that cMyBP-C-AAbs may serve as early predictive indicators of deteriorating cardiac function and patient outcome in ACS patients prior to the infarction.

Blunt Cardiac Injury in the Severely Injured - A Retrospective Multicentre Study.

Directory of Open Access Journals (Sweden)

Marc Hanschen

Full Text Available Blunt cardiac injury is a rare trauma entity. Here, we sought to evaluate the relevance and prognostic significance of blunt cardiac injury in severely injured patients.In a retrospective multicentre study, using data collected from 47,580 patients enrolled to TraumaRegister DGU (1993-2009, characteristics of trauma, prehospital / hospital trauma management, and outcome analysis were correlated to the severity of blunt cardiac injury. The severity of cardiac injury was assessed according to the abbreviated injury score (AIS score 1-6, the revised injury severity score (RISC allowed comparison of expected outcome with injury severity-dependent outcome. N = 1.090 had blunt cardiac trauma (AIS 1-6 (2.3% of patients.Predictors of blunt cardiac injury could be identified. Sternal fractures indicate a high risk of the presence of blunt cardiac injury (AIS 0 [control]: 3.0%; AIS 1: 19.3%; AIS 2-6: 19.1%. The overall mortality rate was 13.9%, minor cardiac injury (AIS 1 and severe cardiac injury (AIS 2-6 are associated with higher rates. Severe blunt cardiac injury (AIS 4 and AIS 5-6 is associated with a higher mortality (OR 2.79 and 4.89, respectively as compared to the predicted average mortality (OR 2.49 of the study collective.Multiple injured patients with blunt cardiac trauma are at high risk to be underestimated. Careful evaluation of trauma patients is able to predict the presence of blunt cardiac injury. The severity of blunt cardiac injury needs to be stratified according to the AIS score, as the patients' outcome is dependent on the severity of cardiac injury.

Factors affecting cardiac rehabilitation referral by physician specialty.

Science.gov (United States)

Grace, Sherry L; Grewal, Keerat; Stewart, Donna E

2008-01-01

Cardiac rehabilitation (CR) is widely underutilized because of multiple factors including physician referral practices. Previous research has shown CR referral varies by type of provider, with cardiologists more likely to refer than primary care physicians. The objective of this study was to compare factors affecting CR referral in primary care physicians versus cardiac specialists. A cross-sectional survey of a stratified random sample of 510 primary care physicians and cardiac specialists (cardiologists or cardiovascular surgeons) in Ontario identified through the Canadian Medical Directory Online was administered. One hundred four primary care physicians and 81 cardiac specialists responded to the 26-item investigator-generated survey examining medical, demographic, attitudinal, and health system factors affecting CR referral. Primary care physicians were more likely to endorse lack of familiarity with CR site locations (P negatively impacting CR referral practices than cardiac specialists. Cardiac specialists were significantly more likely to perceive that their colleagues and department would regularly refer patients to CR than primary care physicians (P Marketing CR site locations, provision of standardized referral forms, and ensuring discharge summaries are communicated to primary care physicians may improve their willingness to refer to CR.