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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.
111

Effects of low-magnitude high-frequency vibration on disuse-induced atrophied skeletal muscles: correlating structural changes with functional performance. / CUHK electronic theses & dissertations collection

January 2012 (has links)
隨著全球人口老化、普遍的久坐生活方式及外太空技術的迅速發展,肌肉廢用已成為日益嚴峻及影響廣泛的公共健康問題。 肌肉廢用可引起肌肉萎縮及肌肉收縮功能衰退,最終影響患者的日常活動能力及生活的獨立性。 此外,重新使用廢用肌肉可引起肌纖維破壞及肌肉功能進一步損失,使得肌肉萎縮問題更加惡化。 低幅高頻振動治療屬於非入侵性的生物物理治療方法,通過給予溫和的全身性機械刺激達到治療目的,被証實可有效強化肌肉功能及刺激肌纖維肥大,為進行有關低幅高頻振動應用於廢用性肌肉萎縮治療的復康研究提供了充足證據。 本研究科研假說為低幅高頻振動治療能通過調節肌纖維形態及激活具生肌能力的肌衛星細胞,以改善廢用性萎縮肌肉收縮功能及促進其康復。 本研究共分為三個部分第1部分是對大鼠懸尾模型引發後肢廢用性肌肉萎縮進行驗證(TS模型)第2部分是研究低幅高頻振動治療對肌肉收縮功能的作用第3部分是振動治療對肌纖維型態及肌肉衛星細胞的影響。 / 第1部分的研究中,十二隻6月齡雄性SD大鼠被隨機分成懸尾組 (TS, n=6)及對照組 (Nor, n=6)。 在懸尾二十八天後,大鼠的比目魚肌被收取並進行體外肌肉功能檢測。 結果顯示懸尾組的肌肉質量及肌纖維橫切面積均顯著下降 (p<0.001),證明懸尾模型能導致廢用性肌肉萎縮。 功能檢測顯示肌肉收縮功能下降,包括抽搐峰力及最大強直力下降(p=0.011及 p<0.001)。 因此,大鼠懸尾模型可用於研究低幅高頻振動治療對肌肉重用康復過程的作用,即本研究的第2及第3部分。 / 為了驗證本研究的科研假說,七十二隻雄性SD大鼠懸尾28天誘導比目魚肌萎縮後被隨機分為振動治療組 (Vib, n=36) 及重用對照組 (Ctrl, n=36),並於懸尾後的第7、14 及21天取比目魚肌作進一步實驗 (n=6/組/時間點)。 治療組的大鼠於懸尾後接受每星期5天、每天20分鐘的低幅高頻振動治療 (振幅: 0.6g、頻率: 35Hz)直至對應的實驗時間點,而對照組大鼠則如常在籠中活動,其餘條件均相同。 / 第2部分實驗是通過體外肌肉功能檢測系統,分析低幅高頻振動治療對廢用萎縮後重用肌肉收縮功能的作用。 實驗結果顯示,相對於在第7天時的最大強直力,對照組重用肌肉在21天的康復期間肌力增長32% 。 振動治療組中,相對於振動治療7天時的最大強直力,振動治療14天已能夠使重用肌肉得到相近 (34.6%) 力量增長(p=0.033)。 由於兩組在第七天時的最大強直力量並沒有明顯差別,故結果可證明振動治療能提高肌強直力的恢復速度。具體肌肉強直力量(以肌纖維橫切面積常化的肌肉強直力量) 亦能夠證明有關發現。 振動治療組比目魚肌的具體強直力在振動治療14天後大於同期對照組力量 (p=0.001)。 振動治療組的具體強直力在14天時已達到最高並相近於21天時的水平,但對照組於14天至21天時仍有著明顯的上升趨勢,顯示振動治療組的肌肉完全康復速度比對照組的快。 / 第3部分實驗是探討低幅高頻振動治療,對廢用性萎縮肌肉重用過程中的肌纖維肥大及肌衛星細胞激活的作用。 為標記重用過程中激活的肌衛星細胞,本部分的每一隻大鼠處死前14天在皮下植入一顆5-溴氧尿嘧啶核苷 (BrdU) 的緩釋顆粒 (0.22亳克BrdU/ 千克/ 天)。 大鼠比目魚肌在相應實驗時間點離體迅速冷凍後進行低溫橫截切片(厚度: 7微米)。 以肌球蛋白三磷酸腺苷酶染色方法把肌肉切片染色後,即可進行肌纖維的種類及形態學分析。 第21天時,振動治療組的快肌IIB 型纖維橫切面積大於對照組,表明振動治療能刺激快肌IIB 型纖維肥大 (p=0.031)。 此外,快肌IIB 型肌纖維橫切面積與肌強直力是呈正相關的,說明低幅高頻振動治療所加快的肌強直力量康復可能是通過刺激快肌IIB 型肌纖維肥大所致。 振動治療引發的慢肌纖維轉型至快肌纖維的潛能可能被重用所致的快至慢轉型所掩蓋。 從另一角度說明,肌肉重用所導致的快肌纖維轉型至慢肌纖維過程,不受振動治療的影響。 激活的肌衛星細胞則通過5-溴氧尿嘧啶核苷標記方法,以免疫熒光技術進行顯微檢測及分析。 振動治療組肌衛星細胞普遍多於對照組,刺激效果在快肌IIA 型肌纖維中表現更為明顯。 對照組廢用肌肉重用過程中,快肌IIA 型肌纖維中激活的肌衛星細胞數量呈下降趨勢,治療組的卻比對照組高並呈持續上升趨勢。 肌衛星細胞的數量亦發現與肌纖維橫切面積呈正相關。 肌衛星細胞的其中一項主要功能為肌肉修補及康復,有關實驗結果表明,振動治療可能通過激活更多衛星細胞以提高肌肉功能及刺激肌纖維肥大。 / 綜上所述,本研究探討了低震高頻振動治療對廢用性萎縮肌肉的收縮功能、康復過程及其機理的影響。 較佳的肌肉力量產生能力及較大面積的快肌IIB 型纖維,表明了振動治療可促進廢用性萎縮肌肉康復。根據快肌IIA型纖維衛星細胞數量以及活化的衛星細胞同肌纖維橫切面積之間的相關性研究結果,可以推測震動治療促進肌肉修復的可能機理是促進肌衛星細胞的活化。 本研究為低幅高頻振動治療的進一步臨床實驗及未來在快肌纖維相關的肌肉老化問題研究,提供了可靠及充分的依據。 / Muscle disuse becomes a public health issue due to increasing aged population, prevalent sedentary lifestyles and rapidly growing outer space development. It results in muscle atrophy, contractile function loss and ultimately affects the daily life activities. The pathological conditions are even worse off during reloading because of the resulting muscle fiber damages and further functional deterioration. Low-magnitude high-frequency vibration (LMHFV), a biophysical modality providing a mild, non-invasive and systemic mechanical stimulation, has been reported to improve muscle functions and stimulate muscle hypertrophy. In this study, we hypothesized that LMHFV improved the functional outcomes and recovery of disuse-induced atrophied muscle through modulating muscle fiber morphology and activating myogenic satellite cells. The study was divided into three parts: Part 1 for validation of the tail suspension hindlimbs unloading animal model (TS model); Part 2 for testifying the LMHFV effect on functional outcomes; Part 3 for the effects on fiber morphology and satellite cells. / In Part 1 study, twelve 6-month-old male Sprague Dawley (SD) rats were randomly assigned to tail suspension control group (TS, n=6) and normal control group (Nor, n=6). Rats in TS group were tail-suspended for 28 days and of the harvested soleus muscle (Sol) was subjected to the in vitro muscle functional assessment. Muscle atrophy in TS group was confirmed by the significant decrease of Sol muscle mass (Mm) and fiber cross-sectional area (FCSA) (both p<0.001). Functionally, weakening of contractile forces including peak of twitch force (Pt) and maximum tetanic force (Po) were observed in TS (p=0.011 and p<0.001 respectively). The established animal model was used to study the effects of LMHFV on muscle reloading recovery in Part 2 and 3. / To testify the hypothesis, a total of 72 male SD rats with Sol atrophy induced by 28-day TS were used for Part two (n=36) and Part three studies (n=36). In each part of the studies, the rats were randomized into LMHFV treatment group (Vib) and reloading control group (Ctrl), from which Sol were harvested at Day 7, 14 and 21 post-TS (n=6/group/timepoint). The LMHFV treatment (0.6g, 35Hz) was applied to Vib group 20min per day and 5 days per week until the endpoint while Ctrl rats were allowed free-cage movement. / In Part 2 study, the effects of LMHFV on contractile functional outcomes of reloading muscle following TS were evaluated by in vitro muscle functional test. In Ctrl group, 32% increase of Po was found at day 21 when compared with that at day 7. A similar recovery level was already achieved in Vib group by 14 days of treatment; when compared with Vib-Day7, a 34.6% increase of Po was found at day 14 (p=0.033). Specific Po (Po normalized by FCSA) in Vib was significantly larger than Ctrl at day 14 (p=0.001). Plateau of specific Po was observed at day 14 in Vib group while significant increase was observed in Ctrl group from day 14 to day 21. These findings suggested the facilitated recovery of force generating capacity in Sol by LMHFV treatment. / In Part 3 study, the effects of LMHFV on muscle fiber hypertrophy and fiber type transition during reloading as well as on muscle satellite cells (SC) activation were assessed. In order to label activated SC, a bromodeoxyuridine (BrdU) time release pellet (0.22mg BrdU/ kg body mass/ day) was subcutaneously implanted to every rat 14 days before execution. In order to evaluate the fiber morphology and fiber type transition, Sol were harvested at corresponding endpoints and cryosectioned (cross-sections at 7μm) for ATPase staining. The bromodeoxyuridine (BrdU)-labeled activated SCs were revealed on the cryosections by immunofluorescence method. Results showed that fast-twitch type IIB muscle fiber hypertrophy was stimulated by LMHFV with type IIB fiber cross-sectional area (FCSA) in Vib group significantly larger than Ctrl at day 21 (p= 0.031). Interestingly, the type IIB FCSA was positively correlated with the Po measured, which suggested the possible contribution of stimulated type IIB muscle fiber hypertrophy for improving contractile force in Vib. The potential slow-to-fast fiber type transition induced by LMHFV might be masked by reloading-induced fast-to-slow transition in Sol. In other words, the normal fiber type transition in Sol during reloading was not affected by LMHFV. In SC activation assessment, more BrdU-labeled SCs were observed in Vib group. Particularly in fast twitch type IIA muscle fibers, the SC counts were increasing throughout the treatment period. It suggested the specific stimulatory effect of LMHFV on activation of fast twitch fiber SCs. Since SC activation is important for muscle recovery, the current finding suggested the possible contribution of increased SC activation to muscle fiber hypertrophy in response to LMHFV treatment. It was in fact evident from the positive association between SC counts and muscle FCSA found in this study. / In conclusion, LMHFV was beneficial to muscle disuse recovery, as indicated from higher force generating capacity and larger fast twitch type IIB fiber FCSA. The possible mechanism was to stimulate myogenic SC activation for muscle repair, as evident from the elevated fast twitch type IIA fiber SC counts and the association of activated SC counts to fiber FCSA. This study suggests the beneficial effects of LMHFV on muscle disuse rehabilitation and also justifies the future clinical trials on rehabilitation of bed-rest patients. The profound effects of LMHFV specifically on fast-twitch fibers provided solid basis for further study on treating the loss of fast-twitch type II fibers in muscle aging (i.e. sarcopenia). / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Sun, Keng Ting. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 113-130). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / Thesis/Assessment Committee --- p.ii / Abstract --- p.iii / 論文摘要 --- p.vii / Publications --- p.x / Acknowledgement --- p.xi / List of Abbreviations --- p.xiii / Figure Index --- p.xvi / Table Index --- p.xvii / Chapter Chapter 1 --- Introduction and Literature Review --- p.1 / Chapter 1.1 --- Skeletal Muscle --- p.1 / Chapter 1.1.1 --- Muscle Structure and Organization --- p.1 / Chapter 1.1.2 --- Muscle Diversity --- p.5 / Chapter 1.1.3 --- Muscle Contraction and Relaxation --- p.7 / Chapter 1.1.4 --- Muscle Plasticity --- p.10 / Chapter 1.1.5 --- Muscle Mechanosensitivity and Mechanotransduction --- p.13 / Chapter 1.1.6 --- Muscle Satellite Cells --- p.16 / Chapter 1.2 --- Muscle Disuse and Rehabilitation --- p.17 / Chapter 1.2.1 --- Epidemiology and Impact of Muscle Disuse --- p.17 / Chapter 1.2.2 --- Effects of Disuse on Muscle Structure and Contractile Function --- p.18 / Chapter 1.2.3 --- Rehabilitation of Disused Muscle --- p.21 / Chapter 1.2.4 --- Countermeasures for Muscle Disuse --- p.22 / Chapter 1.2.5 --- Muscle Disuse Animal Models - Tail Suspension Hindlimbs Unloading Model --- p.23 / Chapter 1.3 --- Low-Magnitude High-Frequency Vibration Intervention --- p.24 / Chapter 1.3.1 --- Stimulatory Effects of Vibration on Muscle --- p.25 / Chapter 1.4 --- Hypothesis and Objectives --- p.27 / Chapter Chapter 2 --- Materials and Methods --- p.30 / Chapter 2.1 --- Study Design --- p.30 / Chapter 2.1.1 --- Part 1: Validation of Tail-Suspension Model --- p.32 / Chapter 2.1.2 --- Part 2: Effect of LMHFV on Functional Recovery after Tail Suspension --- p.32 / Chapter 2.1.3 --- Part 3: Effect of LMHFV on Muscle Recovery in Cellular and Histological Aspects --- p.33 / Chapter 2.2 --- Tail Suspension- Hind Limbs Unloading Model and Reloading --- p.33 / Chapter 2.3 --- Low-Magnitude High-Frequency Vibration (LMHFV) Treatment --- p.36 / Chapter 2.4 --- Part 1 and Part 2 Studies --- p.39 / Chapter 2.4.1 --- Isolation of Soleus Muscle for Functional Assessment --- p.39 / Chapter 2.4.2 --- In vitro Muscle Functional Test --- p.42 / Chapter 2.5 --- Part 3 Study --- p.50 / Chapter 2.5.1 --- Implantation of Bromodeoxyuridine (BrdU) Pellet for Satellite Cell Labeling --- p.50 / Chapter 2.5.2 --- Preparation of Soleus Muscle (Sol) for Histological and Cellular Studies --- p.51 / Chapter 2.5.3 --- Preparation of Muscle Cryosections --- p.51 / Chapter 2.5.4 --- Muscle Fiber Typing - ATPase Staining Assay --- p.54 / Chapter 2.5.5 --- Activated Satellite Cell Profiling - Immunofluorescence Imaging --- p.55 / Chapter 2.6 --- Statistical Analysis --- p.57 / Chapter Chapter 3 --- Results --- p.58 / Chapter 3.1 --- Part 1: Validation of Tail Suspension Model --- p.58 / Chapter 3.1.1 --- Morphological Assessment --- p.58 / Chapter 3.1.2 --- Functional Assessment --- p.58 / Chapter 3.2 --- Part 2: Effects of LMHFV on Functional Recovery from Tail Suspension --- p.61 / Chapter 3.2.1 --- Morphological Assessment --- p.61 / Chapter 3.2.2 --- Functional Assessment --- p.63 / Chapter 3.3 --- Part 3: Effects of LMHFV on Muscle Recovery in Cellular and Histological Aspects --- p.72 / Chapter 3.3.1 --- Muscle Fiber Typing - ATPase Staining --- p.72 / Chapter 3.3.2 --- Satellite Cells Proliferation --- p.78 / Chapter 3.4 --- Correlation of outcomes from part II and part III studies --- p.83 / Chapter Chapter 4 --- Discussion --- p.90 / Chapter 4.1 --- Beneficial Effects of LMHFV in Disuse-induced Atrophied Soleus Muscle Recovery --- p.92 / Chapter 4.2 --- Facilitated Recovery of Force Generating Capacity by LMHFV Treatment --- p.93 / Chapter 4.3 --- Biphasic Effects of LMHFV in Muscle Contraction and Relaxation Time --- p.95 / Chapter 4.4 --- Specific Hypertrophy on Type IIB Muscle Fiber Stimulated by LMHFV --- p.96 / Chapter 4.5 --- Physiological Fiber Type Adaptation Maintained in LMHFV Treatment --- p.98 / Chapter 4.6 --- Promoted SC Activation by LMHFV and its Possible Roles in Histological Improvement --- p.99 / Chapter 4.6.1 --- Possible Regulatory Mechanisms of LMHFV in Promoting SC Activation --- p.100 / Chapter 4.7 --- Disuse-induced Muscle Atrophy Successfully Developed by Tail Suspension Model --- p.102 / Chapter 4.8 --- Limitations --- p.103 / Chapter 4.8.1 --- In vitro measurement of isolated muscle contractile functions --- p.103 / Chapter 4.8.2 --- Overestimation of satellite cell (SC) counts --- p.104 / Chapter 4.9 --- Future studies --- p.105 / Chapter 4.9.1 --- Effects of LMHFV on Fast muscle --- p.106 / Chapter 4.9.2 --- Parameters of LMHFV treatment --- p.107 / Chapter 4.9.3 --- Clinical Trials --- p.107 / Chapter Chapter 5 --- Conclusions --- p.110 / Bibliography --- p.113
112

Alterações anatomopatológicas em corações de camundongos submetidos à inalação crônica de cocaína crack / Anatomopathological alterations in hearts of mice submitted to chronic inhalation of crack cocaine

Moraes, Alcides Gilberto 24 August 2009 (has links)
A cocaína crack é a forma popular da cocaína nos dias de hoje, em decorrência do baixo custo relativo da droga e da rapidez dos seus efeitos no sistema nervoso central. São conhecidas alterações provocadas pela cocaína no coração de humanos e animais, sendo frequentes graves transtornos no sistema cardiovascular, muitas vezes fatais. Mas diante do crescente e preocupante aumento do uso dessa forma fumada da cocaína, particularmente pelos jovens, tornam-se necessários estudos experimentais utilizando-se a droga in natura, que não se encontra habitualmente disponibilizada para experimentos, diante das dificuldades legais. Este estudo objetivou a avaliação dos efeitos da inalação crônica da cocaína crack no coração de camundongos, tendo sido utilizados 24 animais BALB/c machos, jovens e adultos, 6 animais de cada grupo (n=6), que foram expostos à fumaça originada da queima de 5 g de cocaína, por 5 minutos, 5 dias da semana, durante 39 dias, em um período de dois meses; utilizouse uma câmara de inalação para a manutenção dos animais durante as sessões e os animais do grupo controle, em igual nº (n=6), foram mantidos no biotério em condições favoráveis. A droga teve como origem a apreensão policial (195,2 g) e o seu uso, na pesquisa previamente autorizada pela justiça. A análise farmacológica da droga constatou a presença de 57,66% de cocaína nas pedras de crack, satisfazendo as necessidades para a experiência. A quantificação de cocaína de 212,5 ng/ml no sangue dos animais também foi considerada representativa para os nossos objetivos de pesquisar alterações morfológicas no coração dos camundongos. Os resultados foram analisados pela One-Way-Anova e Modelo Linear Generalizado, e as diferenças consideradas significativas quando p< 0,05. Os estudos mostraram diminuição significativa da media (±DP) de peso dos corações nos animais expostos à droga, adultos e jovens, quando comparados com os grupos controles correspondentes. No grupo jovem, o aumento do número de núcleos, por área ventricular, pode ser relacionada com atrofia miocárdica dos ventrículos, direito e esquerdo (p< 0,001), demonstrada pela morfometria das fibras musculares estriadas cardíacas, utilizando-se o sistema de retículo de pontos. Nos adultos expostos, apesar da diminuição de peso do coração, a morfometria não constatou atrofia de miocárdio de nenhum dos lados (p> 0,05). Nos exames microscópicos das paredes ventriculares, com a coloração da hematoxilina-eosina, foi detectado, discreto número de fibras musculares cardíacas, com perda das estriações e hialinizações do citoplasma, favorecendo apoptose. A morfometria dos vasos coronarianos intramurais, com medições das luzes, camadas médias e adventícias demonstrou diminuição significativa da proporção (razão) luz/parede nos animais expostos, independente da idade, quando comparado com os grupos controle (p=0,001). Esses dados caracterizam a vasoconstrição por provável ação simpaticomimética da droga, justificando uma isquemia relativa no coração e conseqüente aumento da apoptose, bem documentada pela imunoistoquímica através da coloração do TUNEL. Esta imunocoloração marcou extensamente os núcleos de células apoptóticas, nos ventrículos direito e esquerdo dos animais expostos, quando comparado aos animais não expostos (p<0,001). A microscopia óptica com H&E e Picro-sirius sugeriu fibrose peri-adventicial nos animais expostos adultos A quantificação do colágeno, após a polarização, mostrou aumento não significativo, nos ramos coronarianos dos animais expostos adultos e interstício do ventrículo direito dos dois grupos expostos (p>0,05). As pesquisas realizadas com um modelo experimental inédito confirmam alterações anatomopatológicas já descritas na literatura, como a vasoconstrição com isquemia aguda e aumento da apoptose e mostram alterações ainda não referidas, em efeitos crônicos da cocaína, como a diminuição de peso do coração e atrofia do miocárdio. Os estudos, embora tenham limitações por não ter sido isolada outra substância eventualmente presente na amostra teste, constataram achados morfológicos importantes para a saúde pública, que devem ser pesquisados nas autópsias. Novos estudos são recomendados, utilizando-se outros tempos e ambientes de exposição, com e sem a associação de drogas, assim como porcentagens diferentes de cocaína no crack e isolando-se as substâncias presentes na droga in natura. / Crack cocaine is the currently popular form of cocaine, due to its low cost and rapid effects on the central nervous system. Alterations caused by cocaine on the hearts of humans and animals are well known and severe disorders in the cardiovascular system, which are sometimes fatal, are frequent. Considering the growing concern regarding the increase in the use of this smoked form of cocaine, especially by young individuals, it becomes necessary to carry out experimental studies using the drug in its natural form, which is not usually available for experiments due to legal difficulties. The present study aimed at assessing the effects of the chronic inhalation of crack cocaine on the hearts of mice. A total of 24 BALB/c male animals were used in the experiment, both young and old, with 6 animals in each group (n=6), which were exposed to crack cocaine smoke that resulted from the burning of 5 g of cocaine, for 5 minutes, 5 days a week, for 39 days, except on weekends and holidays, during a two-month period. An inhalation chamber was used to keep the animals during the sessions, whereas the same number of animals from the control group (n=6) were kept at the animal facility of the institution under favorable conditions. The drug had been originally apprehended by the police in the course of criminal investigations and its use in research was previously authorized by the Department of Justice. The pharmacological analysis of the drug verified the presence of 57.66% of cocaine in the crack rocks, which satisfied the criterion used for the experience. The quantification of cocaine at 212.5 ng/mL in the blood of the animals was also considered representative for our objectives of assessing morphological alterations in the hearts of mice. The results were analyzed by One-Way-ANOVA and Generalized Linear Model, and the differences were considered significant when p<0.05. The studies showed a significant difference in the mean (±SD) weight of the hearts of the animals exposed to the crack cocaine smoke, both young and adult ones, when compared to the corresponding control groups. In the young group, the increased number of nuclei per ventricular area might be related to the myocardial atrophy of the right and left ventricles (p<0.001), demonstrated by the morphometry of the striated heart muscle fibers, using the system of point reticulum. In the exposed adult animals, in spite of the decreased heart weight, the morphometry did not show myocardial atrophy in neither side (p>0.05). The microscopic assessment of the ventricular walls, carried out with hematoxylin and eosin (H&E) staining, showed a small number of heart muscle fibers with loss of striations and hyalinization of the cytoplasm, which favored apoptosis. The morphometry of the intramural coronary vessels, with lumen, medial and adventitial layer measurement, showed a significant decrease in the lumen/wall ratio in exposed animals, regardless of age, when compared to the control group (p=0.001). These data characterize vasoconstriction, due to the probable sympatheticomimetic action of the drug, which justifies a relative ischemia of the heart and a consequent increase in apoptosis, well documented by immunohistochemistry through TUNEL staining. This immunostaining extensively identified the nuclei of apoptotic cells in the right and left ventricles of the exposed animals, when compared to the non-exposed animals (p< 0.001). Optical microcopy with H&E and Picrosirius suggested periadventitial fibrosis in the adult exposed animals. Collagen quantification after polarization showed a non-significant increase in the coronary branches of the adult exposed animals and in the right ventricular interstitium in the two exposed groups (p>0.05). The present study, carried out using a novel experimental model, confirmed the presence of anatomopathological alterations that had been previously described in the literature, such as vasoconstriction with acute ischemia and increased apoptosis and showed alterations that had not been previously reported as being chronic effects of cocaine, such as decreased heart weight and myocardial atrophy. Although there were limitations, considering that other substances eventually present in the test sample were not identified, the present study demonstrated important morphological findings for public health, which must be studied in autopsies. Further studies are recommended, using other exposure durations and environments, with and without the association of drugs, as well as different percentages of cocaine in crack rocks and isolating the substances present in the drug in its natural form.
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Estudo do desenvolvimento morfológico fetal e pós-natal dos sulcos cerebrais / Study of the fetal and post-natal morphological development of the sulci of the brain

Nishikuni, Koshiro 12 September 2006 (has links)
O estudo foi realizado através de avaliação de 214 hemisférios cerebrais, de 107 espécimes humanos, com a idade variando desde 12 semanas de gestação até 8 meses pós-natal. A idade gestacional dos fetos foi calculada através do seu peso corpóreo. Os fetos com malformações congênitas ou com encéfalos danificados foram excluídos. Após a fixação do encéfalo em solução de formol a 10%, foi removida a aracnóide para a análise dos sulcos do cérebro, os quais foram então estudados, desde o seu aparecimento, até sua formação completa. A principal finalidade desse estudo foi estabelecer os padrões de desenvolvimento morfológico dos sulcos cerebrais característicos de cada idade gestacional. Tendo como base a análise dos resultados, foram estabelecidas tabelas de referências cronológicas pertinentes à formação de cada sulco em toda superfície do cérebro. / The study was done through the analysis of 214 brain hemispheres of 107 human brains, with their ages ranging from 12 weeks of gestation to 8 months of postnatal life. The gestational age was calculated from their body weight. The fetuses with congenital abnormalities and or damaged brains were excluded from the study. After the brain fixation with 10% formalin, the arachnoid was removed for the study of the sulci and fissures of the brain, since their appearance until their complete development. The aim of this anatomical study was to establish a reliable sulci morphological pattern characteristic of each gestational age. Based in our findings, reference tables pertinent to the appearance of each sulci of all brain surface were built and are here presented.
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Estudo histomorfométrico comparativo do colágeno e elastina na pele abdominal humana após perda ponderal maciça / Histomorphometric comparative study of collagen and elastin in human abdominal skin of massive weight loss patient

Orpheu, Simone Cristina 27 March 2009 (has links)
O aumento da prevalência da obesidade mórbida constitui um problema de saúde pública global. A obesidade mórbida pode ser definida por um índice de massa corpórea ( IMC ) superior a 35 Kg/ m²; vem acompanhada por diversas comorbidades e determina custos sócio-econômicos elevados. O único método efetivo a longo prazo no tratamento da obesidade mórbida, na atualidade, é a cirurgia bariátrica. Os procedimentos cirúrgicos para tratar a obesidade foram estimulados sobretudo pelo advento de técnicas videolaparoscópicas com menor morbidade pós-operatória e recuperação precoce. O sucesso operatório da cirurgia bariátrica representa perda de até 50% do excesso de peso dos pacientes em prazos variáveis de aproximadamente 24 meses. Após tal período, o processo de emagrecimento será refletido como excesso e flacidez cutânea generalizados e inicia-se a busca pela melhora da imagem corporal. A realização das cirurgias plásticas de contorno corporal exige ampla compreensão das peculiaridades clínicas desse paciente, e dos riscos de complicações, além de expectativas viáveis quanto aos resultados estéticos. Após as cirurgias de contorno corporal, passado o período pós-operatório recente, constata-se a manutenção de flacidez cutânea residual em graus variados. A obesidade interfere na qualidade dos componentes da pele humana. Entretanto, não há estudos específicos em relação à pele do paciente após perda ponderal maciça. Nesse estudo observacional histomorfométrico realizado entre 2006 e 2008, o autor avalia em biópsias de pele humana da região abdominal epigástrica e hipogástrica, o teor de colágeno e elastina em pacientes após perda ponderal maciça comparativamente a pacientes sem antecedentes de obesidade. Analisando a pele abdominal de mulheres não obesas ( controles epigástricos=15 e controles hipogástricos=25 ) e mulheres após tratamento dessa morbidade ( casos=40), verificou-se neste estudo com significância estatística aceita como p<0,05 que: a) na região epigástrica, o teor de colágeno foi superior no grupo controle em comparação ao grupo de casos; b) na região epigástrica, o teor de fibras elásticas foi superior nos casos; c) na região hipogástrica, não houve diferença estatisticamente significante no teor de colágeno entre os grupos estudados; d) na região hipogástrica, o teor de fibras elásticas foi superior no grupo controle / Morbid obesity is an increasing health problem and it is defined as a body mass index greater than 35 kg/m² with severe obesity related comorbidity or a body mass index greater than 40 kg/m² without comorbidity. The combined direct and indirect cost of obesity has been elevated. Bariatric surgery remains the only durable option for weight loss in the morbidly obese.Advanced laparoscopy procedures, as less invasive therapy, have contributed to fast recovery and acceptable perioperative morbidity. Results of bariatric surgery can reach about 50% of excess weight loss with a 2 year follow-up. As patients lose weight, they get laxity skin and their interest in body contouring surgery begins.Plastic surgery in massive weight loss patient demands attention to reduce risks and viable expectations concern to aesthetic results. However, after body contouring surgery, patients can keep up some laxity or folds of excess skin. Obesity changes the components of skin, but there arent definitive studies about skin in massive weight loss patients. In this histomorphometric comparative study, biopsies of human female abdominal skin were analysed in quantity of collagen and elastic fibers in controls (non obese patients, epigastric topography n=15 and hypogastric topography n=25 ) in comparison to massive weight loss patients (n=40). After statistical analyses with p<0,05 was demonstrated that: a)in epigastric topography, the quantity of collagen was higher in control group; b) in epigastric topography, the quantity of elastic fibers was higher in case group; c) in hypogastric topography, there werent diferences in the quantity of collagen between cases and controls; d) in hypogastric topography, the quantity of elastic fibers was higher in control group
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Estudo crítico da anatomia do retalho neurovascular do músculo oblíquo interno com análise histomorfométrica e da incidência de alterações degenerativas dos seus pedículos arteriais / Critical study of the anatomy of the neurovascular flap of the internal oblique muscle with histomorphometric analysis and incidence of degenerative changes of its arterial pedicles

Alberto Yoshikazu Okada 24 November 2014 (has links)
Em 2002 foi descrito o retalho neurovascular de músculo oblíquo interno com um pedículo vascular e dois pedículos nervosos longos para tratamento em tempo único da paralisia facial, que permitiu a reanimação da região bucal e orbital, simultaneamente. Apesar das inúmeras vantagens teóricas deste retalho, há escassez de informações a respeito de suas características anatômicas. Neste estudo foi realizada dissecção em dezoito cadáveres frescos e não formolizados, num total de 36 retalhos retalhos neurovasculares do musculo oblíquo interno (MOI). Foram realizadas medidas diretas com o uso de paquímetro digital de alta precisão, onde foram analizados o comprimento dos pedículos vasculares, o comprimento dos pedículos nervosos e a espessura, área e volume do músculo. Um fragmento de 0,5 cm proximal dos pedículos vasculares foram coletados e enviados para análise histomorfométrica. Na histomorfometria foi mensurado o diâmetro externo dos pedículos arteriais e venosos. A incidência de alterações degenerativas das artérias foi estudada, analisando alterações da camada íntima e da camada média. A vascularização do retalho neurovascular do músculo oblíquo interno tem como pedículo dominante a circunflexa Iiaca profunda (CIP) e pedículos secundários oriundos da subcostal e 11ª intercostal posterior (11ª ITC). Os pedículos subcostal e 11ªITC tem origem no forâmen intervertebral de T11 e T12, e são pedículos neurovasculares. O comprimento médio dos pedículo CIP, subcostal e 11ªITC foi de, respectivamente, 10,8cm (± 2), 13,2cm (± 0,70) e 12,5cm (± 1,25). Houve diferença estatística no comparação entre as médias dos comprimentos (p < 0,001), sendo subcostal > 11ªITC > CIP. Os nervos subcostal e 11ªITC tiveram o mesmo comprimento do pedículo vascular, uma vez que foram seccionados no mesmo ponto, e mediram respectivamente, 13,2cm (± 0,70) e 12,5cm (± 1,25). O músculo do retalho teve espessura média de 0,8 m (±0,14), área média de 4,4cm² (± 1,55) e volume médio de 3,47cm3 (± 1,24). O diâmetro das artérias CIP, subcostal e 11ªITC foram respectivamente de 1,3mm (± 0,32), 0,74mm (± 0,24) e 0,71mm (± 0,23). A análise estatística demonstrou que CIP > subcostal = 11ªITC. As alterações degenerativas da parede da artéria foram analisadas nas camadas íntima e média. Alterações da camada íntima foram observados em 32,4% da CIP (grau I/leve= 20,6%, grau II/moderado=11,8%), 17,6% da subcostal (grau I/leve=11,8%, grau II/moderado=2,9% e grau III/grave=2,9%) e 25,8% da 11ªITC (grau I/leve=22,6% e grauII/moderado=3,2%). Não houve diferença estatística na incidência de alterações intimais entre as artérias (p=0,516). Em relação às alterações da camada média, observou-se a incidência de 23,5% na CIP (grau I= 17,6% e grau II= 5,9%), 32,4% na subcostal (grau I= 26,5% e grau II= 5,9%) e 19,4% na 11ªITC (grau I= 12,9% e grau II= 6,5%). Na análise comparando as incidências de alterações da camada média entre os vasos não houve diferença estatística (p=0,323). O comprimento do nervo subcostal é mais longo que o nervo 11ªITC e foram semelhantes aos relatados na literatura, o que possibilita a anastomose no nervo facial contralateral em tempo único. O músculo oblíquo interno permite a transferência de um retalho com volume bastante reduzido, que pode ser favorável no contorno facial. Quanto às alterações degenerativas, os três pedículos apresentam incidências semelhantes. O maior diâmetro dentre as artérias foi da CIP, em comparação com os demais pedículos. O pedículo vascular da CIP, apresenta um posicionamento mais superficial e sua dissecção é menos trabalhosa. Quando dissecado até sua origem, se torna mais longo e facilita o posicionamento do retalho. Com isso, atinge um maior número de vasos receptores, facilitando a anastomose microcirúrgica / In 2002, the neurovascular internal oblique muscle flap, with one vascular pedicle and two long nerve pedicles, was described for single stage treatment of facial paralysis, allowing the simultaneous reanimation of the oral and orbital regions. Despite the numerous theoretical advantages of this flap, limited information is available regarding its anatomical features. Eighteen fresh, nonembalmed cadavers were dissected, providing a total of 36 flaps. The lengths of the vascular and nerve pedicles and the thickness, area, and volume of the muscle were analyzed. A 0.5-cm proximal fragment of the vascular pedicles was collected and subjected to histomorphometric analysis. The outer diameter of the arterial and venous pedicles and degenerative changes in the intima and medial layers were measured by histomorphometry. The dominant vascular pedicle of the neurovascular internal oblique muscle flap is the deep circumflex iliac (DCI), and secondary neurovascular pedicles arise from the subcostal and 11th posterior intercostal (11th ITC). The mean lengths of the DCI, subcostal and 11th ITC pedicles were 10.8 ± 2 cm, 13.2 ± 0.70 cm and 12.5 ± 1.25 cm, respectively. A significant difference was observed in the mean lengths of the pedicles (p < 0.001), with the length of the subcostal being greater than that of the 11th ITC, which was in turn greater than that of the DCI. The subcostal and 11th ITC nerves were of the same length as the vascular pedicle because they were sectioned at the same point. The muscle had a thickness of 0.8 ± 0.14 cm, an area of 4.4 ± 1.55 cm2 and a volume of 3.47 ± 1.24 cm3. The diameters of the DCI, subcostal and 11th ITC arteries were 1.3 ± 0.32 mm, 0.74 ± 0.24 mm and 0.71 ± 0.23 mm, respectively. Statistical analysis showed that DCI diameter > subcostal diameter = 11th ITC diameter. Degenerative changes of the artery wall in the intima and medial layers were analyzed. Changes in the intima were observed in 32.4% of the DCI, 17.6% of the subcostal and 25.8% of the 11th ITC. In the medial layer, there was an incidence of 23.5% in the DCI, 32.4% in the subcostal and 19.4% in the 11th ITC.The length of the subcostal nerve was longer than the 11th ITC nerve and was similar to the length reported in the literature, it allows single-stage anastomosis in the contralateral facial nerve. The internal oblique muscle provides a flap with a reduced volume to be transferred to the face, which may result in fewer changes in facial contour. The three pedicles display similar incidences of degenerative changes. The diameter of the DCI artery is greater than those of the other pedicles, its vascular pedicle has a more superficial position, and its dissection is less laborious. When dissected to its origin, it becomes longer and facilitates positioning of the flap. Being longer, reaches a greater number of receptor vessels and facilitates microsurgical anastomosis
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Reparo de defeito osteocondral no joelho de coelhos utilizando centrifugado de medula óssea autóloga / Repair of osteochodral defect in the knee of rabbits using autologous bone marrow centrifuged

Rodrigo Bezerra de Menezes Reiff 08 September 2010 (has links)
A cartilagem articular, por sua natureza avascular, apresenta uma capacidade limitada de regeneração. Uma abordagem terapêutica para o tratamento de defeitos da cartilagem consiste na utilização de células ou tecidos aplicados ao local da lesão. O objetivo deste estudo foi avaliar o efeito da aplicação de centrifugado de medula óssea autóloga em lesões osteocondrais no joelho de coelhos, em comparação com um grupo controle de lesões osteocondrais sem preenchimento, analisando o comportamento histológico destes grupos em função do tempo. Foram utilizados doze coelhos da raça Nova Zelândia, albinos, machos, adultos, submetidos a uma lesão osteocondral, de 4 mm de diâmetro e 3 mm de profundidade, em ambos os joelhos, na região da tróclea femoral. Nos joelhos direitos, que constituíram o Grupo Estudo, o defeito osteocondral foi preenchido por um coágulo de células mesenquimais, obtidas por centrifugação de um aspirado da medula óssea e selado com cola de fibrina. Nos joelhos esquerdos, que constituíram o Grupo Controle, o defeito osteocondral não recebeu qualquer preenchimento. Os animais foram divididos em três grupos de quatro coelhos, estudados após oito, 16 e 24 semanas. Os resultados foram descritos com base em uma escala de pontuação histológica que avaliou a morfologia celular, a reconstrução do osso subcondral, o aspecto da matriz, o preenchimento do defeito, a regularidade da superfície e a conexão das margens. A análise estatística foi realizada pelo Teste t-student para dados pareados na comparação entre Grupo Estudo e Grupo Controle. Para as comparações através do fator temporal, utilizou-se o Teste ANOVA one way. Com 5% de confiança, rejeitou-se a hipótese de igualdade entre os Grupos Estudo e Controle. Notou-se uma distância decrescente entre os escores dos Grupos Estudo e Controle com o aumento do tempo, bem como uma tendência crescente do valor da escala para o Grupo Controle. Concluiu-se que a aplicação de centrifugado de medula óssea em defeitos osteocondrais no joelho de coelhos mostrou melhor resultado na avaliação histológica, em comparação ao Grupo Controle. Analisando a evolução dos grupos através do tempo, houve uma aproximação de seus escores histológicos, sobretudo pelo aumento observado no Grupo Controle / The articular cartilage, due to its avascular nature, presents a limited regeneration capacity. A therapeutical approach to the treatment of cartilage defects consists of the utilization of cells or tissues applied to the lesion site. The aim of this study was to evaluate the effect of applying autologous bone marrow centrifuged in osteochondral lesions in the knees of rabbits, compared to a control group of osteochondral lesions without any filling, analyzing the behavior of these groups in terms of time. Twelve adult albino male New Zealand rabbits were used being submitted to an osteochondral lesion of 4 mm in diameter and 3 mm deep in both knees, at the femoral trochlea area. On the right knees, which comprised the Study Group, the osteochondral defect was filled by a clot of mesenchymal cells, obtained by centrifugation of an aspirate from bone marrow and sealed with fibrin glue. On the left knees, which comprised the Control Group, the osteochondral defect did not get any filling. The animals were divided into 3 groups of 4 rabbits, and studied after eight, 16 and 24 weeks. The results were described based on a histological grading scale which took into account the cell morphology, the subchondral bone reconstruction, the matrix staining, the filling of the defect, the surface regularity and the bonding of the edges. The statistical analysis was made by the t-student Test for paired data in the comparison between the Study Group and the Control Group. For the comparisons made by the time factor, it was used the ANOVA Test one way. With 5% level of confidence, the hypothesis of equality between the Study and Control Groups was rejected. It was observed a decreasing distance between scores of the Study and Control Groups as time increased, as well as an increasing tendency of the scale value for the Control Group. It was concluded that the application of autologous bone marrow centrifuged in osteochondral defects in the knees of rabbits showed better result in histological evaluation, in comparison to the Control Group. By analyzing the evolution of the groups through time, there was an approach of their histological scores, especially by the increase observed in the Control Group
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Avaliação de variáveis potencialmente preditivas de má evolução da recidiva da hepatite C em pacientes submetidos a transplante de fígado, com ênfase nos achados anátomo-patológicos / Evaluation of potentially predictive findings of poor outcome in recurrent chronic hepatitis C after liver transplantation, with emphasis on histopathological parameters

Rodrigo Schuler Honorio 05 February 2010 (has links)
Introdução: Hepatite crônica recidivada (HCR) é a regra após o transplante hepático (TH) em pacientes infectados pelo vírus da hepatite C (VHC), provocando progressão de fibrose mais acelerada no órgão transplantado do que no fígado nativo. Vários estudos têm apontado que, dentre os pacientes transplantados por doença terminal relacionada ao VHC, há padrões distintos de evolução pós-transplante, influenciados por diversos aspectos clínicos, demográficos, laboratoriais e histopatológicos. Objetivos: Identificar alterações precoces associadas à gravidade da doença recidivada, com ênfase nos achados histopatológicos no TH e nas biópsias de seguimento. Métodos: Foi avaliada uma coorte retrospectiva de 41 pacientes que se submeteram a TH entre 1992 e 2004. Dados clínicos foram recuperados dos prontuários médicos e todas as biópsias de fígado foram reavaliadas. Foram estudadas em especial a primeira biópsia após o primeiro mês (PAT) e a primeira biópsia com diagnóstico de hepatite crônica (PHC) de cada paciente. Estas duas biópsias foram também submetidas ao estudo das células estreladas hepáticas através da marcação por -actina de músculo liso. A presença de esteatose e dos parâmetros de hepatite crônica foi quantificada em todas as biópsias dentro dos diferentes períodos do pós-transplante. Resultados: A idade média no transplante foi de 51 anos, com 72% dos pacientes do sexo masculino. O tempo médio de seguimento histopatológico (tempo entre o transplante e a última biópsia hepática realizada) foi de 2234 dias (785-4640). A taxa global anual de progressão de fibrose (TPF) foi de 0,62 (escore de Ishak), a partir da qual os pacientes foram classificados no grupo de fibrosadores rápidos (FR),quando TPF > 0,62, e no grupo de fibrosadores lentos (FL),quando TPF <0,62.O tempo para o diagnóstico histopatológico de HCR, os fatores ligados ao doador e os achados histopatológicos precoces associados ao diagnóstico de hepatite crônica não se apresentaram diferentes de forma significante entre os dois grupos. Rejeição celular aguda foi mais prevalente nos FL (p=0,043), embora o grupo dos FR tenha apresentado em média maior número de episódios de rejeição (p=0,036). Observou-se um aumento do índice de massa corporal (IMC) nos FL e um decréscimo do IMC nos FR entre o transplante e a última biópsia realizada (0,049). O grupo dos FR apresentou maior quantidade de esteatose no fígado nativo explantado (p=0,026) e mostrou uma tendência a ter uma menor quantidade de esteatose nas biópsias entre um mês e um ano após o transplante (p=0,079), comparado ao grupo dos FL. Os FR também apresentaram maior deposição de lipofuscina na PAT (p=0,024) e na PHC (p=0,048). FR e FL exibiram padrões distintos de infiltrado inflamatório lobular na PHC, com um infiltrado predominantemente linfocitário nos FR e misto nos FL (p=0,043). Foram também observados padrões distintos de siderose na PAT, que era em células de Kupffer nos FR e concomitante em células de Kupffer e hepatócitos nos FL. Maior quantidade de células estreladas, avaliadas na PHC por exame imuno-histoquímico, foi encontrada na região portal/septal nos FR (p=0,057). As demais alterações histopatológicas não alcançaram significância estatística como preditoras de progressão da doença. Conclusão: Algumas alterações histopatológicas que não estão diretamente associadas ao diagnóstico de hepatite crônica podem contribuir para a compreensão da patogênese da HCR e, adicionalmente, auxiliar na identificação precoce dos pacientes com má evolução após o TH. Se fatores relacionados ao metabolismo lipídico (esteatose hepática e variação de IMC) têm função protetora contra progressão da fibrose ou se resultam diretamente do estado clínico dos pacientes é uma questão que merece estudos adicionais / Background: Recurrent chronic hepatitis (RCH) is the rule after liver transplantation (LT) in hepatitis C virus (HCV) infected patients, with a faster fibrosis progression in allograft than in native liver. Many studies have pointed out that, even in the group of patients transplanted for HCV end-stage disease, there are distinct outcomes due to the influence of several clinical, demographic, laboratorial and histopathological factors. Objectives: Evaluate earlier changes that could be associated to severity of disease recurrence, with emphasis on histopathological findings at LT and follow up biopsies. Method: A retrospective cohort of forty one HCV infected patients who underwent LT between 1992 and 2004 was studied. Clinical data were recovered from hospital files and all liver tissue specimens were reviewed. The first liver biopsy after first month post-LT (FAF) and the first biopsy with chronic hepatitis (FCH) were considered to each patient. Expression of -smooth muscle actin in hepatic stellate cells by immunohistochemistry was also examined in these biopsies. Additionally, steatosis and chronic hepatitis parameters were quantified in all biopsies in each period after LT. Results: The mean age at LT was 51 yr; 72% were male; the median histological follow-up (time between LT and last liver biopsy) was 2234 days (785-4640) and the overall annual rate of fibrosis progression (RFP)was 0.62 (Ishak s score). Patients were classified in fast fibrosers (FF)when RFP>0.62,and when RFP<0.62.Time to histopathological diagnosis of RCH, early histopathological changes related to chronic hepatitis diagnosis and donor factors were not significantly different between both groups. Acute cellular rejection was more prevalent in SF (p=0.043), although FF presented significantly higher number of episodes than SF (p=0.036). It was observed an increase in BMI on FF and an decrease in BMI on SF between transplantation and the time of last liver biopsy (p=0.049). FF showed higher steatosis degree in native explanted liver (p=0.026) and showed a trend toward a lower steatosis degree between one month and one year post-LT (p=0.079). FF also presented higher lipofuscin deposition at FAF (p=0.024) and at FCH (p=0.048). FF and SF showed distinct patterns of lobular inflammatory infiltrate in FHC, with a predominantly lymphocytic type in FF and a mixed one in SF (p=0.043). A distinct pattern of iron deposition in FAF, predominantly in Kupffer cells in FF and in both Kupffer cell and hepatocyte in SF was also detected. Hepatic stellate cells were more prevalent in FF when examined in portal/septal area by immunohistochemical expression of -smooth muscle actin in FHC (p=0.057). All other histological findings did not reach statistical significance as predictors of faster disease progression. Conclusion: Some minor histopathological changes not usually associated to chronic hepatitis diagnosis might contribute to our understanding of the RCH pathogenesis and could be useful in identifying potentially worse outcome patients after LT. If factors related to lipid metabolism (liver steatosis and BMI variation) could protect against fibrosis progression or are direct consequences of the patient´s clinical status deserves further evaluation
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Fatores associados às alterações morfométricas crânio-encefálicas durante o envelhecimento / Morphometric brain and skull changes during ageing and their related factors

Renata Eloah de Lucena Ferretti 06 October 2008 (has links)
INTRODUÇÃO: Existem alterações na morfologia encefálica durante o envelhecimento, que vão além da atrofia cerebral. Ainda deve ser considerado se essas alterações estão presentes em indivíduos sem comprometimento cognitivo e quais são os fatores associados a elas. OBJETIVO: Identificar se existem alterações morfométricas crânio - encefálicas em indivíduos sem comprometimento cognitivo e se essas alterações podem ser correlacionadas com fatores sócio- demográficos e clínicos, em uma série brasileira de casos autopsiados. METODOLODIA: Foi conduzido um estudo no Serviço de Verificação de Óbitos da Capital, onde 414 indivíduos necropsiados, com 50 anos ou mais de idade, foram submetidos à avaliação clínica completa e à análise morfométrica crânioencefálica (perímetro cefálico, peso, volume e densidade encefálicos). As correlações entre as alterações morfométricas cerebrais e os fatores associados (variáveis sócio demográficas e clínicas) foram obtidos por meio de análise uni e multivariadas. RESULTADOS: Amostra composta por 39,6% de mulheres e 60,4% de homens, com idade média de 68,5 (± 11,9 DP) e 66,2 (± 10,2 DP), respectivamente; maioria branca. Foi observada redução do perímetro cefálico com a idade, significante entre as mulheres, e associação discreta entre os homens. Peso e volume encefálicos diminuem com a idade. O peso médio do encéfalo da amostra toda foi de 1219,2 g (± 140,9 DP), e o volume médio foi de 1217,1 mL (± 152,3 DP). Homens apresentaram valores maiores de peso e volume encefálicos, e a redução foi mais pronunciada entre as mulheres. A densidade encefálica não se alterou em função da idade. Houve redução nos valores totais e corrigidos de peso e volume encefálicos, em algumas condições clínicas, mas apenas algumas se mostraram associadas com as reduções de peso e volume de acordo com a análise multivariada. A escolaridade se mostrou um fator protetor contra a redução de peso e volume encefálicos. CONCLUSÕES: Observouse que existem alterações morfométricas cerebrais no envelhecimento normal e, dentre os fatores associados a essas alterações, a maioria esta relacionada com o estilo de vida. Estes resultados permitem demonstrar que hábitos adequados devem ser implementados ao longo da vida visando o envelhecimento saudável / INTRODUCTION: Previous studies have led to the consensus that there are changes in brain morphology during aging, that go beyond brain atrophy. One important aspect to understand is wether there are morfometric brain changes in subjects without cognitive impairments and what are their correlations. OBJECTIVE: To describe whether there are morfometric brain and skull changes in cognitively normal elderly subjects, and if they can be correlated to some selected socio-demographic and clinical factors, in a large autopsy series from Brazil. METHODS: A cross sectional study was conducted in São Paulo Autopsy Service, where 414 autopsied subjects, 50 years and older, were clinically assessed and morphometrical encephalic and skull measurements (cephalic perimeter, brain weight, volume and density) were taken. Correlations among brain and skull changes and factors associated were obtained through, univariate and multivariated analysis. RESULTS: Sample was composed by 39,6% of females and 60,4% of males, with mean age of 68,5 (± 11,9 SD) and 66,2 (± 10,2 SD), respectivelly; mostly caucasians. There is a reduction of cephalic perimeter with age in females and a discrete decrease among men. Brain weight and brain volume decresed with aging. The mean brain weight was 1219,2 g (± 140,9 DP), and the mean brain volume was 1217,1 mL (± 152,3 DP), men presented with higher values for brain weight and volume than women, and the decrease in brain weight and volume were more pronounced in women than in men. Density has not decreased with aging. It has been observed a reduction in total and corrected brain weight and volume in some clinical conditions, but only some of them were estatistically significant in the multivariate analysys. Litteracy has shown to be a protective factor against the reduction of weight and volume. CONCLUSIONS: It was observed that there are morphometrical brain and skull changes during ageing, most related to lyfe style along lifetime. Results indicates that adequate habits must be implemented during lifetime aiming successfull ageing
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Esteato-hepatite não alcoólica e esteatose em hepatite crônica pelo vírus C: prevalência e relações entre dados demográficos e clínico-laboratoriais com parâmetros histopatológicos / Nonalcoholic steatohepatitis and steatosis in chronic hepatitis C: prevalence and the relationship between demographic, clinical and laboratory data with histopathological parameters

Marcia Ferreira da Costa 02 March 2010 (has links)
A hepatite crônica pelo vírus C é a principal causa de doença hepática crônica progressiva e complicações relacionadas, como a cirrose hepática e o carcinoma hepatocelular. O estadiamento de fibrose e a graduação da atividade necroinflamatória são excelentes preditores de progressão da doença na hepatite crônica pelo vírus C (HCVC). A epidemia global de obesidade e diabetes mellitus é responsável pela crescente incidência da doença hepática gordurosa não alcoólica, caracterizada por achados histológicos que variam da esteatose pura até a esteato-hepatite não alcoólica (EHNA), com potencial risco de evolução para a cirrose hepática e suas complicações. Na HCVC, fatores virais e do hospedeiro podem contribuir para a associação com a doença hepática gordurosa não alcoólica. Não há consenso sobre a prevalência de esteatose e esteato-hepatite não alcoólica em pacientes com HCVC, com ampla variabilidade na dependência do genótipo viral, fatores metabólicos da população em estudo e variáveis histológicas utilizadas para a definição. Objetivos: a) Definir a prevalência de esteatose hepática e da esteato-hepatite não alcoólica em pacientes com hepatite crônica pelo vírus C; b) Avaliar a relação entre variáveis clínico-laboratoriais e diferentes graduações de parâmetros histopatológicos; c) Avaliar a influência da EHNA na progressão da fibrose; d) Determinar os fatores virais e do hospedeiro associados a diferentes grupos histológicos, assim definidos: hepatite crônica pelo vírus C (HCVC), hepatite crônica com esteatose (>5%), hepatite crônica associada à esteato-hepatite não alcoólica (esteatose + fibrose perissinusoidal); e) Determinar fatores virais e do hospedeiro associados aos grupos HCVC, HCVC com esteatose e HCVC com EHNA, considerando estadiamento maior de fibrose à biópsia inicial. Métodos: Em 81 pacientes com HCVC seguidos no ambulatório de hepatites crônicas, parâmetros clínico-laboratoriais foram relacionados ao estadiamento da fibrose em biópsias pareadas. Dentre os dados clínicos, a síndrome metabólica foi definida pelo critério do ATP III. À biópsia inicial, achados histopatológicos de HCVC e doença hepática gordurosa não alcoólica foram graduados como ausente/leve ou moderado/intenso. Posteriormente, excluindo os pacientes com o genótipo do VHC tipo 2, dados clínicos e laboratoriais e estágios de fibrose 0-1 ou 2-4 foram analisados em pacientes com hepatite crônica pelo vírus C divididos em três grupos: HCVC sem esteatose, HCVC com esteatose e HCVC com esteato-hepatite não alcoólica (EHNA), definida pela associação com balonização e fibrose perissinusoidal. Resultados: A idade avançada esteve associada a estágio maior de fibrose e atividade inflamatória portal e periportal; o escore de APRI AST / Platelets Relation Índex foi associado a estágios maiores de fibrose e maior atividade necroinflamatória. Na análise multivariada, o perfil lipídico da síndrome metabólica foi associado à fibrose perivenular enquanto a glicemia elevada esteve associada ao hialino de Mallory-Denk. Esteatose isolada esteve presente em 35 (43.2%) e associada a EHNA em 21 (25.9%) dos pacientes. O genótipo 3 do vírus da hepatite C foi mais prevalente nos pacientes com HCVC com esteatose ou EHNA, porém evolução para estágios maiores de fibrose associou-se ao genótipo viral 1 (p= 0.000). A presença de HCVC + EHNA esteve associada com fibrose 2 em pacientes com menos de 45 anos, independentemente do sexo. Sobrepeso ou obesidade também estiveram associados à fibrose intensa (p< 0.05). Em biópsias pareadas, o perfil lipídico de síndrome metabólica foi o único parâmetro associado com progressão da fibrose (p= 0.012). Conclusão: a) A associação de esteatose e esteato-hepatite não alcoólica é elevada em pacientes com HCVC, sendo mais frequente no genótipo viral 3; b) Fatores metabólicos, como o sobrepeso ou obesidade e a presença do perfil lipídico da síndrome metabólica, estiveram associados à esteatose e EHNA em pacientes com HCVC; c) A associação de NASH com hepatite crônica pelo vírus C pode modificar a evolução da doença e demandar atenção cuidadosa desses pacientes. / Chronic hepatitis C is the leading cause of progressive liver damage and related complications, such as cirrhosis and primary hepatocellular carcinoma. Fibrosis stage and necro-inflammatory activity grade are good predictors of disease progression in chronic hepatitis C (CHC).The global epidemic of obesity and diabetes are associated with the increasing incidence of nonalcoholic fatty liver disease (NAFLD), ranging from the pure steatosis to nonalcoholic steatohepatitis (NASH), the latter with the potential to progress to cirrhosis and its complications. In CHC patients, viral and host factors may contribute to the association with NAFLD. There is no consensus about the prevalence of steatosis and NASH in CHC patients, with variability depending on the genotype, host metabolic conditions and histological variables. Objectives: a) To define the prevalence of steatosis and nonalcoholic steatohepatitis in CHC patients; b) To assess the relationship between various clinical and laboratory data and the grading of histological parameters; c) To evaluate the influence of NASH in the progression of fibrosis; d) To determine viral and host factors associated with different histopathological groups classified as: CHC alone, CHC with steatosis ( > 5%) and CHC with NASH (steatosis + perisinusoidal fibrosis); e) To determine viral and host factors associated with higher stages of fibrosis in the three groups. Methods: We investigated clinical and laboratory data in 81 CHC patients under scrutiny in a public tertiary hospital and related them to fibrosis stage at paired biopsies. Among clinical data, metabolic syndrome was defined according to ATPIII. At initial biopsy, histopathological features of chronic hepatitis C and nonalcoholic steatohepatitis were graded as absent/light or moderate/severe. Later on, except for genotype 2 patients, we analysed clinical, biochemical data and stage of fibrosis 0-1 vs. 2-4 among CHC patients divided into three groups: without steatosis, with steatosis and with nonalcoholic steatohepatitis (NASH). Results: In multivariate analysis, lipid profile of metabolic syndrome was associated with perivenular fibrosis whereas elevated glycemia levels were associated with Mallorys hyaline. Steatosis was present in 35 (43.2%) and NASH in 21 (25.9%) patients. HCV genotype 3 was more prevalent among CHC patients associated with steatosis or NASH but higher fibrosis stages were associated with HCV genotype 1 (p= 0.000). The presence of CHC + NASH was associated with fibrosis 2 in patients under 45 years, irrespective of sex (p < 0.05). Overweight and obesity (p < 0.05) were also related to severe fibrosis (p < 0.05). In paired biopsies, lipid profile of metabolic syndrome was the only parameter associated with progression of fibrosis (p= 0.012). Conclusion: a) Steatosis and nonalcoholic steatohepatitis are frequent histopathological features in our CHC patients, especially in HCV genotype 3; b) Metabolic factors, like overweight, obesity and lipid profile of metabolic syndrome were associated with steatosis and NASH in CHC patients; c) The association of NASH in chronic hepatitis C may modify the outcome of CHC and demand close examination.
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Análise histomorfométrica do colo femoral em pacientes com e sem fratura do colo do fêmur / Histomorphometric evaluation of the femoral neck in patients with or without femoral neck fractures

Caio Gonçalves de Souza 12 June 2007 (has links)
Foi analisada a parte trabecular do colo do fêmur de 13 pacientes do sexo feminino, com idade acima dos 60 anos, com o método da histomorfometria óssea. Sete destas pacientes tiveram fratura do colo do fêmur. Todas foram submetidas a artroplastia do quadril. O exame de densitometria óssea não mostrou diferença significativa. Na espessura média das trabéculas não houve diferença significativa, porém o número de trabéculas foi menor e a separação entre elas foi maior no grupo com fraturas. / A histomorphometry evaluation of the trabecular part of the femoral neck was performed in 13 women over 60 years old submitted to hip arthroplasty. Seven of these patients had a femoral neck fracture. The bone mineral density showed no difference between both groups. The average thickness did not have significant between both groups, but the trabecular separation was higher and the number of trabecular bone was lower in the fracture group.

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