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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Evaluation of surgical methods for sleep apnea and snoring

Holmlund, Thorbjörn January 2016 (has links)
Background: Snoring and obstructive sleep apnea (OSA) are both common disorders with a number of negative health effects. The safety and efficacy of treating snoring and OSA surgically have been questioned and there has been a lack of studies in the field. Aims: 1) To investigate the frequency of serious complications, including death, after surgery for the treatment of snoring and sleep apnea; 2) to evaluate the effect on daytime sleepiness after radiofrequency surgery of the soft palate in snoring men with mild or no OSA; 3) to evaluate the effect of tonsillectomy on sleep apnea in adults with OSA and tonsillar hypertrophy; 4) to investigate the morphology and cytoarchitecture of muscle fibers in human soft palatal muscles with immunohistochemical and morphological techniques. Methods and results: In paper 1, a retrospective database study. All Swedish adults who were treated surgically because of snoring or OSA from January 1997 to December 2005 were identified in the National Patient Register. None of the surgically treated patients died in the peri- and postoperative period. Severe complications were recorded in 37.1 of 1,000 patients treated with uvulopalatopharyngoplasty (UPPP), in 5.6 of 1,000 patients after uvulopalatoplasty (UPP) and in 8.8 of 1,000 patients after nasal surgery. In paper 2, the study was designed as a randomized, controlled trial. 35 snoring men with mild or no OSA were randomized to either radiofrequency or sham surgery of the soft palate. Radiofrequency surgery was not found to be effective since there was no significant difference between the two groups in relation to the Epworth Sleepiness Scale (ESS) or apnea-hypopnea index (AHI) at follow-up. Paper 3 was a prospective study, including 28 patients with an AHI of >10 and with large tonsils. In these patients, tonsillectomy was an effective treatment for OSA; the mean AHI was reduced from 40 units/h to 7 units/h (p<0.001), and the mean ESS was reduced from 10.1 to 6.0 (p<0.001) at the six-month follow-up after surgery. Minor and moderate swallowing dysfunction was found in seven of eight patients investigated before surgery and the swallowing function improved in 5 of them after surgery, while no one deteriorated. In paper 4, we investigated the morphology and cytoarchitecture in normal soft palate muscles. Human limb muscles were used as reference. The findings showed that the soft palate muscle fibers have a cytoskeletal architecture and cellmembrane complex that differs from that of the limb muscles. Conclusions No case of death related to surgery was found among 4,876 patients treated with UPPP, UPP or nasal surgery for snoring or OSA in Sweden between 1997 and 2005. Radiofrequency surgery of the soft palate has no effect on daytime sleepiness, snoring or apnea frequency in snoring men with mild or no OSA. Tonsillectomy can be an effective treatment for OSA in adults with large tonsils. A subgroup of muscle fibers in the human soft palate appears to have special biomechanical properties and their unique cytoarchitecture must be taken into account while assessing function and pathology in oropharyngeal muscles. / Snarkning och obstruktiv sömnapné (OSA) är idag en global folksjukdom. Snarkning är det ”oljud” som uppstår när luftvägen under sömn förminskas och vävnaden börjar vibrera under andning. Vid obstruktiv sömnapné faller vävnaden samman och blockerar luftflödet till lungorna. Ett andningsuppehåll, en s.k. apné inträffar. Ett andningsuppehåll kan pågå allt ifrån några sekunder till mer än en minut och kan uppstå hundratals gånger per natt. För att klassificeras som en patologisk apné enligt internationell standard måste andningsuppehållet vara längre än 10 sek. Snarksjukdomen förvärras sannolikt över tid och övergår succesivt i obstruktiv sömnapné med ökande antal andningsuppehåll under sömn. Detta leder till ett stresspåslag för kroppen med oftast uttalad dagtrötthet och en mängd negativa hälsoeffekter. Snarksjukdom och sömnapné ökar risken för bl.a. högt blodtryck och hjärt-kärlsjukdom samt också för att den drabbade ska orsaka trafikolyckor på grund av försämrad koncentrationsförmåga och trötthet. En del av den negativa utvecklingen från snarkning till sömnapné anses bero på att snarkvibrationer kan ge neuromuskulära skador i gom och svalg. Dessa vävnadsskador anses också vara orsaken till att personer som snarkat länge ofta uppvisar störd sväljningsfunktion i form av felsväljning, där maten i uttalade fall hamnar i luftstrupen istället för i matstrupen. I dagsläget är förstahandsbehandling vid sömnapné CPAP, en mask som placeras över näsa och mun och som skapar ett övertryck i luftvägen vilket förhindrar att luftvägen faller samman och att andningsstopp uppstår. CPAP har enligt flera studier den bästa effekten mot andningsuppehåll. En annan vanlig behandling är en bettskena som för underkäken nedåt och framåt så att luftvägen bli mer öppen. Bettskenan är en vanlig och effektiv behandlingsmetod för personer utan kraftig övervikt vid vanemässig snarkning eller måttlig sömnapné. För ett tjugotal år sedan var kirurgi förstahandsmetoden vid behandling av snarkning och måttlig sömnapné. Man utförde då ofta operationer i svalg och gomm, s.k. gomplastiker. Bruket av kirurgisk behandling har dock minskat med tiden, dels p.g.a. biverkningar men också för att det saknades vetenskapliga studier som bevisade att kirurgin gav önskad och långsiktig effekt. Kirurgi utgör dock fortfarande ett komplement till behandling av snarkning och sömnapné när CPAP eller bettskena av olika skäl inte fungerar eller kan tolereras av patienten. 8 Även barn kan lida av snarkning och sömnapné men behandlingsprinciperna för barn skiljer sig från dem hos vuxna och berörs inte i avhandlingen. I denna avhandling studeras: i) biverkningsfrekvenser efter olika typer av snarkkirurgi, ii) effekten av radiovågsbehandling i mjuka gommen på vuxna män med snarkning, iii) effekten av att operera bort halsmandlarna på vuxna med sömnapné och stora halsmandlar, iv) muskelvävnadens struktur och molekylära uppbyggnad i mjuka gommen hos friska personer som inte snarkar. Avhandlingen består av fyra delstudier: 1. En registerstudie med kartläggning av svåra biverkningar efter kirurgi i form av uvulopalatopharyngoplastik, uvulupalatoplastik samt näskirurgi för behandling av sömnapné och snarkning och utfört i Sverige mellan åren 1997-2005. Studien omfattade 4 876 patienter. Inga dödsfall noterades. Komplikationsrisken var störst vid operationer där man tog bort delar av mjuka gommen samt halsmandlarna, där i snitt 37 av 1000 opererade fick biverkningar, framförallt p.g.a. infektioner eller blödningar. 2. I en prospektiv, randomiserad placebostudie utvärderades effekten av radiovågsbehandling i mjuka gommen vid snarkning och lindrig sömnapne. Trettiotvå patienter lottades till att få radiovågsbehandling eller placebo behandling. Patienterna visste inte vilken grupp de tillhörde. Vid uppföljning efter 12 månader var det inga statistiska belägg för att radiovågsbehandling minskade vare sig antal andningsuppehåll eller dagtrötthet. 3. Effekten av att ta bort halsmandlarna på patienter med stora halsmandlar och olika grad av sömnapné utvärderades i denna studie. Totalt deltog 28 patienter. Vid uppföljning 6 månader efter operationen hade antalet andningsuppehåll sjunkit drastiskt, från i snitt 40 till 7 andningsuppehåll per timme nattsömn. Inga allvarliga biverkningar uppstod. Dessa fynd talar för att man som förstahandsmetod ska erbjuda patienter med sömnapné och stora halsmandlar att ta bort halsmandlarna. 4. I detta projekt undersökte vi utseendet och uppbyggnaden av cellskelettet i två normala muskler i mjuka gommen hos friska personer utan känd snarkning och sömnapné. Muskler från armar och ben användes som referens. Fynden i studien visar att de normala muskelfibrernas uppbyggnad i mjuka gomen skiljer sig från jämförade muskler i armar och ben. Detta kan vara ett uttryck för en evolutionär utveckling för att möjligöra de komplexa funktioner som krävs av svalgets muskulatur. 9 Sammanfattningsvis kan vi konstatera: Att inga dödsfall har skett i Sverige efter operationer i gom, svalg eller näsa, utförda för att behandla snarkning och sömnapné under åren 1997 till 2005. Att radiovågsbehandling av mjuka gommen hos snarkande män med lindrig sömnapné inte har någon effekt på dagtrötthet, snarkning eller andningsuppehåll vid uppföljning efter 12 månader. Metoden kan därför inte rekommenderas. Att när man opererar bort stora halsmandlar på personer med andningsuppehåll så leder detta ofta till att andningsuppehållen minskar drastiskt. Metoden kan därför oftast rekommenderas som en förstahandsbehandling för denna patientgrupp. Att mjuka gommens muskelfibrer är uppbyggda på ett unikt sätt indikerar att deras specifika biomekaniska egenskaper skiljer sig från referens muskler i armar och ben.
32

Spatial distribution and modulation of nitric oxide synthase in a hypertensive rat model

Yannaccone, Andrew 06 February 2012 (has links)
There are gaps in the fundamental understanding of the expression of nitric oxide synthases (NOS) in the microvasculature. We examined co-localization of NOS1 (nNOS), NOS2 (iNOS) and NOS3 (eNOS) in the spinotrapezius muscle of young adult male Wistar-Kyoto (WKY) and Spontaneously Hypertensive (SHR) rats according to fiber type using immunohistochemistry and brightfield microscopy. Data regarding fiber distribution, population and morphology data were collected. Alkaline phosphatase staining was used to determine capillary density and average number of capillaries around a fiber. Gel electrophoresis and Western blot techniques were used to compare myosin heavy chain (MHC) protein expression with fiber type population data and to determine NOS1-3 protein expression in whole muscle homogenate. This study should provide a more accurate understanding of differences in NOS expression between these two strains of rats.
33

Modelagem matemática e simulação de potenciais de ação de unidades motoras. / Mathematical modeling and simulation of motor unit action potencials.

Mugruza Vassallo, Carlos Andrés 23 June 2006 (has links)
Este trabalho apresenta a modelagem matemática e a simulação de potenciais de ação de unidades motoras de músculos de vertebrados visando a posterior simulação do eletromiograma. Para conseguir isso, inicialmente se fez uma compilação de dados existentes para a distribuição das fibras musculares (FBs) nas unidades motoras (MUs) de vários músculos, e as modelagens matemáticas descritos na literatura para o potencial de ação de uma FB (SFAP) e de uma MU (MUAP). Com base nos dados fisiológicos, primeiro se localizou as FBs em um músculo, por meio de uma aproximação de que as FBs estão rodeadas de outras seis no músculo. Para conseguir isto se construiram hexágonos concêntricos por MU, e posteriormente se localizou as FBs nas MUs, cobrindo uma faixa entre 75 e 2000 FBs, o que corresponde a músculos distais de mamíferos. Depois se fez uma aproximação para a distribuição de 170000 FBs nas 272 MUs da cabeça medial do músculo gastrocnêmio (MG) do gato, conseguindo numa primeira simulação localizar cerca de 70% das FBs para cada MU. Com esta localização das FBs no músculo baseados nos dados da literatura se aproximaram os retardos axonais por uma distribuição gaussiana, com média de 2 ms (gato) ou 10 ms (homem) e com desvio padrão de menos de 0,5 ms, desprezando o atraso axonal nas ramificações axonais, que foi estimado no máximo 29 vezes menor. Para a geração do SFAP trabalhou-se com dois modelos, um analítico, o qual resulta em simulações numéricas demoradas, e, outro numérico baseado na convolução da corrente com uma função peso. Para o modelo numérico dobrou-se imaginariamente o comprimento das FBs, para levar em conta o erro computacional de fim de fibra. O modelo numérico resultou em um tempo de simulação 30 vezes menor que o analítico. Adicionalmente, para simular a captação externa (i.e. na pele), fez-se uma aproximação para a função que modela os eletrodos de superfície de secção circular localizados a uma distância maior que 1,79 mm das FBs, mostrando um espectro similar ao reportado na literatura. Finalmente, os MUAPs obtidos resultavam com formas de onda e espectros similares ao descrito na literatura. Além disto, em certos casos, obtiveram-se MUAPs com indentações, seja localizando as junções neuromusculares em bandas da ordem de 1 mm de espessura, seja quando o tempo de atraso axonal foi considerado junto com a velocidade de condução da FB em função da raiz quadrada do diâmetro da FB. Foram feitas simulações para os MG e bíceps braquial do homem. Neste último caso, foram obtidos MUAPs similares aos captados para pessoas saludáveis, e foi observada a freqüência de disparos dos potenciais de ação do motoneurônio no espectro do MUAP. Quanto às formas dos agrupamentos das FBs em uma MU, não se obtiveram diferenças significativas para as FBs posicionadas homogênea e aleatoriamente, exceto uma ligeira variação nas amplitudes. No entanto, ocurreu uma mudança na faixa espectral, quando as FBs estavam concentradas. / This work presents the mathematical model and simulation of motor unit action potentials of vertebrate muscles aiming at after simulation of the electromyogram. To obtain this, initially, it was made a compilation of several data about the distribution of muscle fibers (FBs) in motor units (MUs) of many muscles, and the mathematical models of the action potential of a single FB (SFAP) and MU (MUAP), reported in previous works. On the basis of this physiological data, first, the FB was located in a muscle, using an approximation in which the FBs are encircled with other six FBs in the muscle. To reach this, concentric hexagons were constructed to build the surface of the MU, and later the FBs were situated in the MU, covering a range between 75 and 2000 FBs, corresponding to mammals extremity muscles. Later, a new approximation were was madein order to distribute the 170000 FBs in the 272 MUs of the medial head of muscle medialis gastrocnemius (MG) of the cat, reaching, in a first simulation, the localization of almost 70% of the FBs at each MU. With the FBs lalready allocated in the muscle, and based in data of previous works, their axonal delay were approximated by a gaussian distribution, with mean of 2 ms (cat) or 10 ms (man) and standard deviation of less than 0,5 ms, discarding the axonal delay in the axonal branching, that were estimated to affectup to 29 times less. To SFAP generation, two models were used, the first analytical, resulting in delayed numerical simulations, and the other based on convolution of the second derivate of the current with a weight function, where the length of the FBs was imaginarily duplicated, in order to consider the end fiber effect. Using this, a simulation time 30 times lesser than the analytical one was obtained. Additionally, so as to simulate the external recording (i.e. in the skin), it was made an approximation to the function that models the circular shape surface electrodes located at distances greater than 1,79 mm of the FBs, showing a similar spectrum reported. Finally, the waves and spectrum of the simulated MUAPs resulted similar to the ones reported in the literature. Beyond this, in certain cases, MUAPs were simulated with some tuned, either locating the neuromuscular junctions with thickness bands of 1 mm, or, when the axonal delay and the FB muscle fiber conduction velocity were considered as a function of the square root fiber diameter. This was simulated for MUAPs of MG and biceps brachii muscles of human beings, in the last case it has reached the waveforms and tuned found in heath subjects, and it was visualized the mean frequency of firing rate at the spectrum. In order to know how much affects grouping for the FBs to waves a MU, they were not found significant differences with FBs located homogeneously and randomly, except a little variation in the amplitude of the MUAP. However, they presented a change in the spectral bandwidth when the FBs are more concentrated.
34

Caracterização histoquímica das fibras do músculo gastrocnêmio de ratos Wistar submetidos à tenotomia e tenorrafia / Histochemical caracterization of gastrocnemius muscle fibers in Wistar rats submitted to tenotomy and tenorrhaphy

Alves, Paulo Henrique de Matos 10 November 2010 (has links)
As lesões tendíneas são uma das mais comuns que ocorrem nos esportes, sua freqüência é de 10 a 55% de todas as lesões ocorridas. A cabeça medial do músculo gastrocnêmio (GCm) é constituído por duas regiões bem distintas: uma região profunda \"vermelha\" e uma região superficial \"branca\". Dada essa característica de distribuição dos tipos de fibras, torna-se possível determinar se, no mesmo músculo, a tenotomia afeta as fibras de maneira diferente, dependendo do tipo de fibra predominante em cada região. O objetivo deste estudo foi avaliar o efeito da tenotomia e tenorrafia experimental na GCm. Foram usados 38 ratos Wistar machos pesando aproximadamente 300 g divididos em três grupos: Controle (C), Tenotomizado (T) e Tenorrafiado (R), avaliados aos 14 e 21 dias pós-cirurgia. Os animais foram mantidos sob as mesmas condições de alojamento, alimentação, temperatura umidade e luz. No grupo T, o tendão calcâneo do membro pélvico esquerdo foi dissecado e seccionado transversalmente no terço médio. No grupo R, este mesmo tendão foi imediatamente submetido à sutura de Kessler modificada após a tenotomia. Foram realizadas seções de 10 µm de espessura em criostato e, em seguida, estas secções foram submetidas às técnicas da hematoxilina e eosina, picro-sirius, NADH-tr e para análise em microscopia eletrônica de transmissão A significância estatística das diferenças inter-grupos foi determinada pela análise de variância, (ANOVA) e foi aceito p <0,05. Foram encontradas diferenças significativas entre os grupos C, T e R. Observou-se uma grande variação no tamanho e formato das fibras musculares e, ainda, uma desorientação e degeneração das miofibrilas e desorganização dos sarcômeros nos animais do grupo T. Ambos os grupos, T e R, apresentaram diminuição da área de secção transversa e comprimento da GCm. / Tendon injuries are one of the most commonly occurring in sports, its frequency is 10 to 55% of all injuries. The medial head of gastrocnemius muscle (GCm) consists of two clearly distinct regions: a deep region \"red\" and, a superficial region \"white\". Because of that characteristic distribution of fiber types, it becomes possible to determine if the same muscle tenotomy affects differently, depending on the predominant fiber type in each region. The aim of this study was to evaluate the effect of experimental tenotomy and tenorrhaphy on GCm. We used 38 male Wistar rats weighing approximately 300 g divided into three groups: control (C), tenotomized (T) and Tenorraphized (R). They were evaluated at 14 and 21 days after the surgery. Animals were kept under the same conditions of accommodation, feeding, temperature, humidity and light. In T group, calcaneal tendon of the left pelvic limb was dissected and sectioned in the middle third. In R group, the same tendon was immediately submmitted to the modified Kessler suture after tenotomy. Sections were performed in 10 µm thick in a cryostat and they were then stained according to hematoxylin and eosin, Picrosirius, NADH-tr methods and they were analyzed by transmission electron microscopy. The statistical significance of inter-group differences was determined by analysis of variance (ANOVA) and was accepted p<0.05. Significant differences were found between C, T and R groups. There was a wide variation in size and shape of muscle fibers and also a disorientation and degeneration of myofibrils and disorganization of sarcomeres in T group. Both T and R groups showed a decrease in cross-sectional area and length of the GCm.
35

Modelagem matemática e simulação de potenciais de ação de unidades motoras. / Mathematical modeling and simulation of motor unit action potencials.

Carlos Andrés Mugruza Vassallo 23 June 2006 (has links)
Este trabalho apresenta a modelagem matemática e a simulação de potenciais de ação de unidades motoras de músculos de vertebrados visando a posterior simulação do eletromiograma. Para conseguir isso, inicialmente se fez uma compilação de dados existentes para a distribuição das fibras musculares (FBs) nas unidades motoras (MUs) de vários músculos, e as modelagens matemáticas descritos na literatura para o potencial de ação de uma FB (SFAP) e de uma MU (MUAP). Com base nos dados fisiológicos, primeiro se localizou as FBs em um músculo, por meio de uma aproximação de que as FBs estão rodeadas de outras seis no músculo. Para conseguir isto se construiram hexágonos concêntricos por MU, e posteriormente se localizou as FBs nas MUs, cobrindo uma faixa entre 75 e 2000 FBs, o que corresponde a músculos distais de mamíferos. Depois se fez uma aproximação para a distribuição de 170000 FBs nas 272 MUs da cabeça medial do músculo gastrocnêmio (MG) do gato, conseguindo numa primeira simulação localizar cerca de 70% das FBs para cada MU. Com esta localização das FBs no músculo baseados nos dados da literatura se aproximaram os retardos axonais por uma distribuição gaussiana, com média de 2 ms (gato) ou 10 ms (homem) e com desvio padrão de menos de 0,5 ms, desprezando o atraso axonal nas ramificações axonais, que foi estimado no máximo 29 vezes menor. Para a geração do SFAP trabalhou-se com dois modelos, um analítico, o qual resulta em simulações numéricas demoradas, e, outro numérico baseado na convolução da corrente com uma função peso. Para o modelo numérico dobrou-se imaginariamente o comprimento das FBs, para levar em conta o erro computacional de fim de fibra. O modelo numérico resultou em um tempo de simulação 30 vezes menor que o analítico. Adicionalmente, para simular a captação externa (i.e. na pele), fez-se uma aproximação para a função que modela os eletrodos de superfície de secção circular localizados a uma distância maior que 1,79 mm das FBs, mostrando um espectro similar ao reportado na literatura. Finalmente, os MUAPs obtidos resultavam com formas de onda e espectros similares ao descrito na literatura. Além disto, em certos casos, obtiveram-se MUAPs com indentações, seja localizando as junções neuromusculares em bandas da ordem de 1 mm de espessura, seja quando o tempo de atraso axonal foi considerado junto com a velocidade de condução da FB em função da raiz quadrada do diâmetro da FB. Foram feitas simulações para os MG e bíceps braquial do homem. Neste último caso, foram obtidos MUAPs similares aos captados para pessoas saludáveis, e foi observada a freqüência de disparos dos potenciais de ação do motoneurônio no espectro do MUAP. Quanto às formas dos agrupamentos das FBs em uma MU, não se obtiveram diferenças significativas para as FBs posicionadas homogênea e aleatoriamente, exceto uma ligeira variação nas amplitudes. No entanto, ocurreu uma mudança na faixa espectral, quando as FBs estavam concentradas. / This work presents the mathematical model and simulation of motor unit action potentials of vertebrate muscles aiming at after simulation of the electromyogram. To obtain this, initially, it was made a compilation of several data about the distribution of muscle fibers (FBs) in motor units (MUs) of many muscles, and the mathematical models of the action potential of a single FB (SFAP) and MU (MUAP), reported in previous works. On the basis of this physiological data, first, the FB was located in a muscle, using an approximation in which the FBs are encircled with other six FBs in the muscle. To reach this, concentric hexagons were constructed to build the surface of the MU, and later the FBs were situated in the MU, covering a range between 75 and 2000 FBs, corresponding to mammals extremity muscles. Later, a new approximation were was madein order to distribute the 170000 FBs in the 272 MUs of the medial head of muscle medialis gastrocnemius (MG) of the cat, reaching, in a first simulation, the localization of almost 70% of the FBs at each MU. With the FBs lalready allocated in the muscle, and based in data of previous works, their axonal delay were approximated by a gaussian distribution, with mean of 2 ms (cat) or 10 ms (man) and standard deviation of less than 0,5 ms, discarding the axonal delay in the axonal branching, that were estimated to affectup to 29 times less. To SFAP generation, two models were used, the first analytical, resulting in delayed numerical simulations, and the other based on convolution of the second derivate of the current with a weight function, where the length of the FBs was imaginarily duplicated, in order to consider the end fiber effect. Using this, a simulation time 30 times lesser than the analytical one was obtained. Additionally, so as to simulate the external recording (i.e. in the skin), it was made an approximation to the function that models the circular shape surface electrodes located at distances greater than 1,79 mm of the FBs, showing a similar spectrum reported. Finally, the waves and spectrum of the simulated MUAPs resulted similar to the ones reported in the literature. Beyond this, in certain cases, MUAPs were simulated with some tuned, either locating the neuromuscular junctions with thickness bands of 1 mm, or, when the axonal delay and the FB muscle fiber conduction velocity were considered as a function of the square root fiber diameter. This was simulated for MUAPs of MG and biceps brachii muscles of human beings, in the last case it has reached the waveforms and tuned found in heath subjects, and it was visualized the mean frequency of firing rate at the spectrum. In order to know how much affects grouping for the FBs to waves a MU, they were not found significant differences with FBs located homogeneously and randomly, except a little variation in the amplitude of the MUAP. However, they presented a change in the spectral bandwidth when the FBs are more concentrated.
36

Metabolic Syndrome Insulin Resistance is Associated with Discordant Distrbution of GLUT4 and the Insulin Receptor in Fast‐Twitch and Slow‐Twitch Muscle Fiber Types

Stuart, Charles A., McCurry, Melanie P., Marino, Anna, South, Mark A., Howell, Mary E.A., Ramsey, Michael W., Stone, Michael H. 24 June 2011 (has links)
Metabolic Syndrome Insulin Resistance Is Associated with Discordant Distribution of GLUT4 and the Insulin Receptor in Fast-Twitch and Slow-Twitch Muscle Fiber Types We have previously shown that We have previously shown that strength training alone improved insulin responsiveness in sedentary controls but not in metabolic syndrome subjects. Immunoblots of metabolic syndrome subjects[apos] muscle homogenates showed training-related increases in GLUT4 and mitochondrial enzymes was half that seen in the controls. To determine if this was due to changes primarily in fast-twitch fibers (strength fibers), we performed immunohistochemical (IHC) studies on muscle sections from these subjects to quantify fiber-specific changes in GLUT4, phospho-AMPK, phospho-mTOR, ATP synthase, and the insulin receptor. Signal intensity in confocal microscopic images was digitally quantified and the amount in each fiber type was adjusted by the fiber composition and the average size of each fiber type. Fiber type was classified using monoclonal antibodies against slow-twitch (type 1 fibers) and fast-twitch (type 2a and 2b fibers) myosin heavy chains. At baseline, both groups had slightly more insulin receptor in slow-twitch fibers, and most of the ATP synthase (mitochondrial marker) was in fast-twitch fibers. In controls, 55% of GLUT4 was in slow-twitch fibers, whereas metabolic syndrome subjects had only 33% of their GLUT4 in slow-twitch fibers. The IHC data showed modest increases in GLUT4 (9-25%), and substantial increases of ATP synthase (55-95%), and insulin receptors (44-104%) in both fiber types in both groups. Training-related increases were seen in phospho-AMPK (25% in slow-twitch, 15% in fast-twitch) only in the control subjects but no change in phospho-mTOR in either subject group. At baseline, metabolic syndrome subjects[apos] muscle had 56% of insulin receptors expressed in slow-twitch fibers, but only 33% of the GLUT4 was in these fibers. Thus, the untrained muscle composition of the metabolic syndrome subjects exhibited a mismatch between insulin receptors and GLUT4 in their fiber-specific distributions. This mismatch may contribute to the insulin resistance seen in the metabolic syndrome and may be involved in the diminished insulin sensitivity response to strength training in these subjects.
37

Η επίδραση διαφορετικού επιπέδου φυσικής δραστηριότητας στο μέγεθος και τύπο μυικών ινών του πολυσχιδούς μυός. Συγκριτική μελέτη ομάδων ασθενών οσφυαλγίας και υγειών ατόμων

Μάζης, Νικόλας 03 May 2010 (has links)
Ανασκόπηση βιβλιογραφίας: Όπως υποστηρίζεται από διάφορες έρευνες οι μυς της οσφυϊκής χώρας και συγκεκριμένα ο πολυσχιδής μυς, παίζουν σημαντικό ρόλο στη σταθερότητα της σπονδυλικής στήλης. Προηγούμενες εργασίες που μελέτησαν τα χαρακτηριστικά του πολυσχιδή μυός σε ασθενείς με οσφυαλγία δεν έχουν συμπεριλάβει στο σχεδιασμό τους την παράμετρο της φυσικής δραστηριότητας. Σκοπός της παρούσας έρευνας ήταν να εξετάσει την διάμετρο και την ποσοστιαία αναλογία των μυϊκών ινών του πολυσχιδή μυός μεταξύ ομάδων ασθενών με οσφυαλγία διαφορετικού επιπέδου φυσικής δραστηριότητας και υγιών ατόμων. Μεθοδολογία: Στη μελέτη συμμετείχαν εθελοντικά 64 ασθενείς με οσφυαλγία. Βασιζόμενοι στο επίπεδο φυσικής δραστηριότητας των ασθενών, το οποίο εκτιμήθηκε με την συμπλήρωση συγκεκριμένου ερωτηματολογίου (IPAQ), δημιουργήθηκαν τρεις (3) ερευνητικές ομάδες. Η διαχωρισμός των τριών ομάδων έγινε ανάλογα με το επίπεδο φυσικής δραστηριότητας ως εξής: χαμηλή (ΧΦΔ), μέση (ΜΦΔ), υψηλή (ΥΦΔ). Επίσης στον σχεδιασμό της έρευνας συμπεριελήφθη μια ομάδα ελέγχου αποτελούμενη από 17 άτομα. Βιοπτικό υλικό, διαστάσεων περίπου 5Χ5Χ10 χιλ., ελήφθη από τον πολυσχιδή μυ στο επίπεδο Ο4-Ο5. Αποτελέσματα: Αντίθετα με την ομάδα ελέγχου, οι ομάδες ασθενών με οσφυαλγία παρουσίασαν στατιστικώς μεγαλύτερη ποσοστιαία αναλογία μυϊκών ινών Τύπου ΙΙ καθώς και μικρότερη διάμετρο και στους δύο τύπους ινών (p<0.05). Τα αποτελέσματα έδειξαν ότι το επίπεδο φυσικής δραστηριότητας δεν επηρέασε τα χαρακτηριστικά του πολυσχιδή μυ καθώς δεν παρατηρήθηκαν σημαντικές διαφορές (p>0.05) στη διάμετρο και ποσοστιαία αναλογία των ινών μεταξύ των ομάδων ΥΦΔ, ΜΦΔ και ΧΦΔ. Διάφορες ιστοπαθολογικές αλλοιώσεις που παρατηρήθηκαν ήταν εμφανέστερες στις ομάδες ασθενών με οσφυαλγία συγκριτικά με την ομάδα ελέγχου (p<0.05). Η διάμετρος και των δύο τύπων μυϊκών ινών ήταν μεγαλύτερη στους άνδρες σε σχέση με τις γυναίκες (p<0.05). Συμπεράσματα: Τα αποτελέσματα της έρευνας έδειξαν ότι το επίπεδο φυσικής δραστηριότητας μεταξύ των ομάδων ασθενών με οσφυαλγία δεν επηρέασε την διάμετρο και ποσοστιαία αναλογία των μυικών τους ινών. Συμπερασματικά, βάση αυτών των ευρημάτων η έρευνα προτείνει ότι τόσο η φυσική αδράνεια όσο και η υψηλή φυσική δραστηριότητα μπορούν να επιφέρουν αρνητικές επιπτώσεις στα χαρακτηριστικά των ινών του πολυσχιδή μυός. / Background: Previous studies examining the multifidus fiber characteristics among low back pain (LBP) patients have not considered the variable of physical activity. The present study sought to investigate the muscle fiber size and type distribution of the lumbar multifidus muscle among LBP patient groups with different physical activity levels and healthy controls. Methods: 64 patients were assigned to one of three groups named according to the physical activity level, determined for each patient by the IPAQ questionnaire. These were low (LPA), medium (MPA) and high (HPA) physical activity groups. A control group comprising of 17 healthy individuals was also recruited. Muscle biopsy samples were obtained from the multifidus muscle at the level L4-L5. Results: In contrast with the control group, LBP patient groups showed a significantly higher Type II fiber distribution as well as reduced diameter in both fiber types (p<0.05). The physical activity level did not have an effect on multifidus characteristics since no significant differences were observed in fiber type and diameter (p>0.05) among LPA, MPA and HPA patient groups. Various pathological conditions were detected which were more pronounced in LBP groups compared to the control (p<0.05). Males had a larger fiber diameter compared to females for both fiber types (p<0.05). Conclusion: The results showed that the level of physical activity did not affect muscle fiber size and type distribution among LBP patients groups. These findings suggest that not only inactivity but also high physical activity levels can have an adverse effect on the multifidus muscle fiber characteristics.
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Associação da proteína sericina ao exercício de natação na regeneração do músculo plantar após lesão compressiva do nervo isquiático de ratos wistar / Association of sericin protein to swimming exercise in plantar muscle regeneration after sciatic nerve compression of Wistar rats

Santana, André Junior 04 August 2017 (has links)
Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-02-23T19:34:28Z No. of bitstreams: 2 André_Santana2017.pdf: 2268024 bytes, checksum: d4eee1d456e910253f049c57a48abf85 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-02-23T19:34:28Z (GMT). No. of bitstreams: 2 André_Santana2017.pdf: 2268024 bytes, checksum: d4eee1d456e910253f049c57a48abf85 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-04 / Peripheral nerve damage causes a number of morphological changes, resulting in functional, nerve and muscle complications. There are several therapeutic measures applied in rehabilitation, such as physical exercise in the aquatic environment, which has been extensively studied in terms of functional improvement, although its regenerative potential needs more evidence. Also, it is important to search for substances with therapeutic potential and that can be used in association with physical exercise, in order to intensify recovery. The protein biopolymer, sericin, obtained from the cocoon of the silkworm (Bombyx mori), presents a series of important regenerative pharmacological effects, with cicatrizant action in the treatment of burns, improvement in the aerobic performance and the oxidation of fat at rest. In this sense, the objective of this study was to analyze the effect of sericin associated or not to physical swimming exercise on the muscular recovery of Wistar rats, submitted to sciatic nerve injury. The experiment was carried out in a sample composed of 40 animals, 10 ± 2 weeks old, randomly divided into five groups: Ct: control; Ls: injury; Being: injury + sericin; Nat: injury + swimming; Ser + Nat: injury + sericina + physical exercise. The animals were anesthetized and submitted to compression injury of the right sciatic nerve. Immediately after the nerve compression, a dose of 100 μL of hydrolyzed sericin was applied to the injured nerve in Ser and Ser + Nat animals. On the other hand, the animals of the Nat and Ser + Nat groups, 72 hours after the injury, were treated with resisted physical exercise of swimming, with overload of 10% of body weight, during three weeks, five days a week. The animals performed fifteen minutes of swimming in the first week, 20 minutes in the second and 25 minutes in the third week. During the treatment, the grip strength of the right pelvic limb of all animals was evaluated. At the end of the experimental period, the animals were anesthetized for dissection and collection of the plantar muscle, and the proximal part was processed and analyzed histomorphologically, and the distal for histoenzymological analysis. Regarding the functional data of muscular strength of grip, morphology and morphometry of the 8 neuromuscular junctions, no significant influence on the neuromuscular regeneration process was observed. The same occurred with the musculoskeletal properties, which did not suffer significant changes in the association of sericin and swimming. Although physical swimming exercise alone was efficient in maintaining the intramuscular conjunctiva, the association with sericin was not able to alter the plantar muscle phenotype, although experimental axonotmosis did so. / Lesões nervosas periféricas causam uma série de alterações morfológicas, resultando em complicações funcionais, nervosas e musculares. Várias são as medidas terapêuticas aplicadas na reabilitação, como, por exemplo, o exercício físico em meio aquático, que vem sendo amplamente estudado no que diz respoieto à melhora funcional, embora seu potencial regenerativo necessite de maiores comprovações. Ainda, é importante a busca de substâncias com potencial terapêutico e que possam ser utilizadas em associação ao exercício físico, de forma a intensificar a recuperação. O biopolímero protéico sericina, obtido do casulo do bicho-da-seda (Bombyx mori), apresenta uma série de efeitos farmacológicos regenerativos importantes, com ação cicatrizante no tratamento de queimaduras, melhora no desempenho aeróbico e na oxidação de gordura em repouso. Nesse sentido, o objetivo deste estudo foi analisar o efeito da sericina associada ou não ao exercício físico de natação sobre a recuperação muscular de ratos Wistar, submetidos à lesão nervosa isquiática. O experimento foi desenvolvido numa amostra composta por 40 animais, com 10±2 semanas de idade, separados aleatoriamente em cinco grupos: Ct: controle; Ls: lesão; Ser: lesão + sericina; Nat: lesão + natação; Ser+Nat: lesão + sericina + exercício físico. Os animais foram anestesiados e submetidos à lesão por compressão do nervo isquiático direito. Imediatamente após a compressão nervosa, nos animais dos grupos Ser e Ser+Nat, foram aplicadas uma dose de 100 μL de sericina hidrolisada sobre o nervo lesionado. Já os animais dos grupos Nat e Ser+Nat, 72 horas após a lesão, foram tratados com exercício físico resistido de natação, com sobrecarga de 10% da massa corporal, durante três semanas, cinco dias por semana. Os animais realizaram quinze minutos de natação na primeira semana, 20 minutos na segunda e 25 minutos na terceira semana. No decorrer do tratamento, avaliou-se a força de preensão do membro pélvico direito de todos os animais. Ao término do período experimental, os animais foram anestesiados para dissecação e coleta do músculo plantar, sendo que a parte proximal foi processada e analisada histomorfologicamente, e a distal para análise histoenzimológica. Com relação aos dados funcionais de força muscular de preensão, morfologia e morfometria das junções neuromusculares, não foi observado influência significativa sobre o processo de regeneração neuromuscular. O mesmo ocorreu com as propriedades músculo esqueléticas, que não sofreram alterações significativas na associação da sericina e da natação. Embora o exercício físico de natação sozinho tenha sido eficiente na manutenção do conjuntivo intramuscular, a associação com sericina não foi capaz de alterar o fenótipo do músculo plantar, embora a axonotmese experimental o tenha feito.
39

Associação da proteína sericina ao exercício de natação na regeneração do músculo plantar, após lesão compressiva do nervo isquiático de ratos Wistar / Association of sericin protein to swimming exercise in plantar muscle regeneration after sciatic nerve compression of Wistar rats

Santana, André Júnior 04 August 2017 (has links)
Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-03-06T17:41:31Z No. of bitstreams: 2 Andre_Santana2017.pdf: 2268027 bytes, checksum: 9d06e9ab0f5b41d9bdfbfbafcbba9200 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-06T17:41:31Z (GMT). No. of bitstreams: 2 Andre_Santana2017.pdf: 2268027 bytes, checksum: 9d06e9ab0f5b41d9bdfbfbafcbba9200 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-04 / Peripheral nerve damage causes a number of morphological changes, resulting in functional, nerve and muscle complications. There are several therapeutic measures applied in rehabilitation, such as physical exercise in the aquatic environment, which has been extensively studied in terms of functional improvement, although its regenerative potential needs more evidence. Also, it is important to search for substances with therapeutic potential and that can be used in association with physical exercise, in order to intensify recovery. The protein biopolymer, sericin, obtained from the cocoon of the silkworm (Bombyx mori), presents a series of important regenerative pharmacological effects, with cicatrizant action in the treatment of burns, improvement in the aerobic performance and the oxidation of fat at rest. In this sense, the objective of this study was to analyze the effect of sericin associated or not to physical swimming exercise on the muscular recovery of Wistar rats, submitted to sciatic nerve injury. The experiment was carried out in a sample composed of 40 animals, 10 ± 2 weeks old, randomly divided into five groups: Ct: control; Ls: injury; Being: injury + sericin; Nat: injury + swimming; Ser + Nat: injury + sericina + physical exercise. The animals were anesthetized and submitted to compression injury of the right sciatic nerve. Immediately after the nerve compression, a dose of 100 μL of hydrolyzed sericin was applied to the injured nerve in Ser and Ser + Nat animals. On the other hand, the animals of the Nat and Ser + Nat groups, 72 hours after the injury, were treated with resisted physical exercise of swimming, with overload of 10% of body weight, during three weeks, five days a week. The animals performed fifteen minutes of swimming in the first week, 20 minutes in the second and 25 minutes in the third week. During the treatment, the grip strength of the right pelvic limb of all animals was evaluated. At the end of the experimental period, the animals were anesthetized for dissection and collection of the plantar muscle, and the proximal part was processed and analyzed histomorphologically, and the distal for histoenzymological analysis. Regarding the functional data of muscular strength of grip, morphology and morphometry of the 8 neuromuscular junctions, no significant influence on the neuromuscular regeneration process was observed. The same occurred with the musculoskeletal properties, which did not suffer significant changes in the association of sericin and swimming. Although physical swimming exercise alone was efficient in maintaining the intramuscular conjunctiva, the association with sericin was not able to alter the plantar muscle phenotype, although experimental axonotmosis did so / Lesões nervosas periféricas causam uma série de alterações morfológicas, resultando em complicações funcionais, nervosas e musculares. Várias são as medidas terapêuticas aplicadas na reabilitação, como, por exemplo, o exercício físico em meio aquático, que vem sendo amplamente estudado no que diz respoieto à melhora funcional, embora seu potencial regenerativo necessite de maiores comprovações. Ainda, é importante a busca de substâncias com potencial terapêutico e que possam ser utilizadas em associação ao exercício físico, de forma a intensificar a recuperação. O biopolímero protéico sericina, obtido do casulo do bicho-da-seda (Bombyx mori), apresenta uma série de efeitos farmacológicos regenerativos importantes, com ação cicatrizante no tratamento de queimaduras, melhora no desempenho aeróbico e na oxidação de gordura em repouso. Nesse sentido, o objetivo deste estudo foi analisar o efeito da sericina associada ou não ao exercício físico de natação sobre a recuperação muscular de ratos Wistar, submetidos à lesão nervosa isquiática. O experimento foi desenvolvido numa amostra composta por 40 animais, com 10±2 semanas de idade, separados aleatoriamente em cinco grupos: Ct: controle; Ls: lesão; Ser: lesão + sericina; Nat: lesão + natação; Ser+Nat: lesão + sericina + exercício físico. Os animais foram anestesiados e submetidos à lesão por compressão do nervo isquiático direito. Imediatamente após a compressão nervosa, nos animais dos grupos Ser e Ser+Nat, foram aplicadas uma dose de 100 μL de sericina hidrolisada sobre o nervo lesionado. Já os animais dos grupos Nat e Ser+Nat, 72 horas após a lesão, foram tratados com exercício físico resistido de natação, com sobrecarga de 10% da massa corporal, durante três semanas, cinco dias por semana. Os animais realizaram quinze minutos de natação na primeira semana, 20 minutos na segunda e 25 minutos na terceira semana. No decorrer do tratamento, avaliou-se a força de preensão do membro pélvico direito de todos os animais. Ao término do período experimental, os animais foram anestesiados para dissecação e coleta do músculo plantar, sendo que a parte proximal foi processada e analisada histomorfologicamente, e a distal para análise histoenzimológica. Com relação aos dados funcionais de força muscular de preensão, morfologia e morfometria das junções neuromusculares, não foi observado influência significativa sobre o processo de regeneração neuromuscular. O mesmo ocorreu com as propriedades músculo esqueléticas, que não sofreram alterações significativas na associação da sericina e da natação. Embora o exercício físico de natação sozinho tenha sido eficiente na manutenção do conjuntivo intramuscular, a associação com sericina não foi capaz de alterar o fenótipo do músculo plantar, embora a axonotmese experimental o tenha feito.
40

Caracterização histoquímica das fibras do músculo gastrocnêmio de ratos Wistar submetidos à tenotomia e tenorrafia / Histochemical caracterization of gastrocnemius muscle fibers in Wistar rats submitted to tenotomy and tenorrhaphy

Paulo Henrique de Matos Alves 10 November 2010 (has links)
As lesões tendíneas são uma das mais comuns que ocorrem nos esportes, sua freqüência é de 10 a 55% de todas as lesões ocorridas. A cabeça medial do músculo gastrocnêmio (GCm) é constituído por duas regiões bem distintas: uma região profunda \"vermelha\" e uma região superficial \"branca\". Dada essa característica de distribuição dos tipos de fibras, torna-se possível determinar se, no mesmo músculo, a tenotomia afeta as fibras de maneira diferente, dependendo do tipo de fibra predominante em cada região. O objetivo deste estudo foi avaliar o efeito da tenotomia e tenorrafia experimental na GCm. Foram usados 38 ratos Wistar machos pesando aproximadamente 300 g divididos em três grupos: Controle (C), Tenotomizado (T) e Tenorrafiado (R), avaliados aos 14 e 21 dias pós-cirurgia. Os animais foram mantidos sob as mesmas condições de alojamento, alimentação, temperatura umidade e luz. No grupo T, o tendão calcâneo do membro pélvico esquerdo foi dissecado e seccionado transversalmente no terço médio. No grupo R, este mesmo tendão foi imediatamente submetido à sutura de Kessler modificada após a tenotomia. Foram realizadas seções de 10 µm de espessura em criostato e, em seguida, estas secções foram submetidas às técnicas da hematoxilina e eosina, picro-sirius, NADH-tr e para análise em microscopia eletrônica de transmissão A significância estatística das diferenças inter-grupos foi determinada pela análise de variância, (ANOVA) e foi aceito p <0,05. Foram encontradas diferenças significativas entre os grupos C, T e R. Observou-se uma grande variação no tamanho e formato das fibras musculares e, ainda, uma desorientação e degeneração das miofibrilas e desorganização dos sarcômeros nos animais do grupo T. Ambos os grupos, T e R, apresentaram diminuição da área de secção transversa e comprimento da GCm. / Tendon injuries are one of the most commonly occurring in sports, its frequency is 10 to 55% of all injuries. The medial head of gastrocnemius muscle (GCm) consists of two clearly distinct regions: a deep region \"red\" and, a superficial region \"white\". Because of that characteristic distribution of fiber types, it becomes possible to determine if the same muscle tenotomy affects differently, depending on the predominant fiber type in each region. The aim of this study was to evaluate the effect of experimental tenotomy and tenorrhaphy on GCm. We used 38 male Wistar rats weighing approximately 300 g divided into three groups: control (C), tenotomized (T) and Tenorraphized (R). They were evaluated at 14 and 21 days after the surgery. Animals were kept under the same conditions of accommodation, feeding, temperature, humidity and light. In T group, calcaneal tendon of the left pelvic limb was dissected and sectioned in the middle third. In R group, the same tendon was immediately submmitted to the modified Kessler suture after tenotomy. Sections were performed in 10 µm thick in a cryostat and they were then stained according to hematoxylin and eosin, Picrosirius, NADH-tr methods and they were analyzed by transmission electron microscopy. The statistical significance of inter-group differences was determined by analysis of variance (ANOVA) and was accepted p<0.05. Significant differences were found between C, T and R groups. There was a wide variation in size and shape of muscle fibers and also a disorientation and degeneration of myofibrils and disorganization of sarcomeres in T group. Both T and R groups showed a decrease in cross-sectional area and length of the GCm.

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