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1.
J Microsc ; 260(3): 326-37, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26280540

RESUMO

A variety of diseases can lead to loss of lung tissue. Currently, this can be treated only symptomatically. In mice, a complete compensatory lung growth within 21 days after resection of the left lung can be observed. Understanding and transferring this concept of compensatory lung growth to humans would greatly improve therapeutic options. Lung growth is always accompanied by a process called angiogenesis forming new capillary blood vessels from preexisting ones. Among the processes during lung growth, the formation of transluminal tissue pillars within the capillary vessels (intussusceptive pillars) is observed. Therefore, pillars can be understood as an indicator for active angiogenesis and microvascular remodelling. Thus, their detection is very valuable when aiming at characterization of compensatory lung growth. In a vascular corrosion cast, these pillars appear as small holes that pierce the vessels. So far, pillars were detected visually only based on 2D images. Our approach relies on high-resolution synchrotron microcomputed tomographic images. With a voxel size of 370 nm we exploit the spatial information provided by this imaging technique and present the first algorithm to semiautomatically detect intussusceptive pillars. An at least semiautomatic detection is essential in lung research, as manual pillar detection is not feasible due to the complexity and size of the 3D structure. Using our algorithm, several thousands of pillars can be detected and subsequently analysed, e.g. regarding their spatial arrangement, size and shape with an acceptable amount of human interaction. In this paper, we apply our novel pillar detection algorithm to compute pillar densities of different specimens. These are prepared such that they show different growing states. Comparing the corresponding pillar densities allows to investigate lung growth over time.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional , Pulmão/anatomia & histologia , Pulmão/fisiologia , Regeneração , Tomografia/métodos , Algoritmos , Animais , Camundongos
2.
Eur Spine J ; 24(4): 864-70, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25281332

RESUMO

PURPOSE: Indication for surgery in spine trauma patients depends on the extent of destruction of the spine. Computer-assisted tomography scan (CAT scan) is not suitable to diagnose type B-injuries. Aim of the study was to investigate whether ultrasound is able to detect destruction of the posterior ligament complex (PLC). METHODS: Twenty-nine patients were included. The results of ultrasound were compared with magnetic resonance imaging (MRI), CAT scan, X-ray, intraoperative findings. Statistical analysis was carried out by an independent observer. RESULTS: In 27 cases both ultrasound and MRI had the same result. In two cases, ultrasound failed to detect ligamentous injury. The sensitivity of ultrasound was 0.82 (CI 0.48-0.98), its specificity: 1. MRI and Ultrasound findings had a strong positive correlation (phi = 0.85, Cohen's kappa: 0.85, with 95 % confidence interval 0.65-1) and a high significance (Fischer's exact test: p < 0.0001). CONCLUSION: Ultrasound may indicate rupture or integrity of PLC in cases where MRI is missing.


Assuntos
Ligamentos Longitudinais/lesões , Traumatismos da Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Ligamentos Longitudinais/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Traumatismos da Coluna Vertebral/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia
3.
J Periodontal Res ; 49(3): 371-81, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23815471

RESUMO

BACKGROUND AND OBJECTIVE: Recently, porcine acellular dermal matrix (PADM) has been proposed as a possible alternative to autogenous grafts in periodontal plastic surgery. The aim of the present study was to investigate the in vitro responses of four different oral cell lines cultured on a novel PADM. Furthermore, tissue reaction to PADM was evaluated histologically after subcutaneous implantation in mice. MATERIAL AND METHODS: Human gingival fibroblasts (HGF), human osteoblast-like cells, human umbilical vein endothelial cells and human oral keratinocytes (HOK) were cultured and transferred on to the PADM. A tissue culture polystyrene surface served as the control. The viability of all tested cell lines on PADM was measured by using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assay and PrestoBlue(®) reagent. The ToxiLight(®) assay was performed to analyze the effect of PADM on adenylate kinase release. PADM was implanted into nude mice subcutaneously and subjected to histological analysis after 21 d. RESULTS: Using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide colorimetric assays, all tested cell lines cultured on PADM demonstrated a significant increase of viability compared to the control group (each p < 0.001) with the exception of HGF and HOK after 3 d (each p > 0.05). According to the PrestoBlue(®) analysis, all cell lines demonstrated a significant increase of viability compared to the control group at the particular points of measurement after 18 h (HGF p < 0.01; human osteoblast-like cells, human umbilical vein endothelial cells, HOK each p < 0.001). No significant cytotoxic effects of PADM on the tested cell lines could be observed, as assessed by changes in adenylate kinase release. Subcutaneous implantation of PADM into nude mice demonstrated good integration with surrounding tissues and significant revascularization of its collagen structure. CONCLUSION: Overall, the results suggest that PADM is a promising substitute for autogenous soft tissue grafts in periodontal surgery.


Assuntos
Derme Acelular , Gengiva/citologia , Gengivoplastia/métodos , Alicerces Teciduais , Adenilato Quinase/análise , Animais , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/fisiologia , Transplante de Células/métodos , Colorimetria/métodos , Corantes , Feminino , Fibroblastos/transplante , Regeneração Tecidual Guiada Periodontal/métodos , Células Endoteliais da Veia Umbilical Humana/transplante , Humanos , Indicadores e Reagentes , Queratinócitos/transplante , Camundongos , Camundongos Nus , Osteoblastos/transplante , Tela Subcutânea/cirurgia , Suínos , Sais de Tetrazólio , Tiazóis , Fatores de Tempo , Engenharia Tecidual/métodos
4.
Clin Oral Investig ; 18(3): 1015-22, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23892503

RESUMO

OBJECTIVES: Bisphosphonate-associated osteonecrosis of the jaw (BP-ONJ) is an adverse side effect of long-term bisphosphonate treatment. One theory of BP-ONJ etiology suggests a negative influence of these agents on angiogenesis and vascularization. This in vivo study analyzed the effects of bisphosphonates on angiogenesis in a 3D Matrigel assay. MATERIALS AND METHODS: Matrigel plugs were implanted into fifty 6-8-week-old female nude mice. Ten animals each were treated either with clodronate, ibandronate, pamidronate, zoledronate, or carrier solution as controls. The microvessel density (MVD), microvessel area (MVA), and microvessel size (MVS) in Matrigel plugs were analyzed after 21 days of treatment by immunohistochemistry and exemplary 3D microvascular corrosion castings. RESULTS: All bisphosphonates induced a statistically significant decrease of MVD (p each <0.001), whereby the nitrogen-containing bisphosphonates (N-BPs) demonstrated a clearly stronger effect than non-nitrogen-containing bisphosphonates (NN-BP) clodronate (control 166, clodronate 99, ibandronate 48, pamidronate 47, zoledronate 35 microvessels/mm(2)). Referring to MVA, similar results could be detected. MVS was significantly increased especially by ibandronate (103 %) compared to control group (p < 0.001). Scanning electron microscope scans of the corrosion castings confirmed these results. CONCLUSIONS: The stronger influence on MVD by N-BPs compared to the NN-BP clodronate may explain for the lack of BP-ONJ after treatment with NN-BPs. CLINICAL RELEVANCE: Ibandronate induced a strong increase of MVS. In combination with the reduced MVD, this could result only in a fractional reduced perfusion which might be an explanation for the lower occurrence of BP-ONJ in patients receiving ibandronate compared to patients receiving pamidronate or zoledronate.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Difosfonatos/farmacologia , Animais , Difosfonatos/efeitos adversos , Camundongos , Camundongos Endogâmicos C57BL
5.
Arch Orthop Trauma Surg ; 134(4): 501-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24531976

RESUMO

INTRODUCTION: The aim of the present study was to determine the anatomical relationship and evaluate the potential interference of today's common distal humerus plates with the medial and lateral collateral ligaments of the elbow. MATERIALS AND METHODS: The elbow joints of 23 embalmed upper extremities were dissected. Three different brands of distal humerus double-plating systems were applied in a standardized fashion. We used a caliper to measure the amount of absolute overlap of the plates on the corresponding collateral ligaments. RESULTS: The data show contact and overlap with the medial and lateral collateral ligaments in all tested medial and lateral plates. The posterolateral and posteromedial plates showed no contact with the ligaments, yet they did contact the posterior joint capsules. The medial plates showed less contact/overlap when compared with the lateral and extended medial plates. CONCLUSION: Based on the present data, we conclude that distal humerus plating using the perpendicular technique with standard-sized medial plates shows the least amount of overlap over the medial and lateral collateral ligaments. The extent of the overlap of the ligaments by the humeral plates is clearly shown in the present study.


Assuntos
Placas Ósseas/efeitos adversos , Ligamentos Colaterais/anatomia & histologia , Articulação do Cotovelo/anatomia & histologia , Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas/efeitos adversos , Úmero/cirurgia , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cadáver , Feminino , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Úmero/anatomia & histologia , Doença Iatrogênica , Instabilidade Articular/etiologia , Masculino
6.
Unfallchirurg ; 116(6): 531-6, 2013 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-22367520

RESUMO

BACKGROUND: This study examines the dimensions of children's fingers and the risk of jam injuries in a 4-mm gap between glass and gasket of power-operated motor vehicle windows. MATERIAL AND METHODS: The diameter of the proximal, middle, and distal phalanx and of the proximal and distal interphalangeal joint of each finger of the right hand of 160 children was measured in a cross-sectional investigation. Six different drawings in cross section of gaskets and glass window panes of current motor vehicle side door windows at a vertical gap of 4 mm were drawn in correct proportion. The larger actual width of the oblique gap between window glass and gasket was measured and related to the diameters of children's fingers. RESULTS: Almost all fingers and joints fit in the largest actual gap of 18 mm between glass and gasket of one seal design. CONCLUSION: The European guideline 74/60/EWG specifications currently pertaining to closing force restriction do not eliminate the risk of potentially serious injury to children's fingers in motor vehicle power windows.


Assuntos
Acidentes de Trânsito/estatística & dados numéricos , Automóveis/estatística & dados numéricos , Traumatismos dos Dedos/epidemiologia , Ferimentos não Penetrantes/epidemiologia , Adolescente , Criança , Pré-Escolar , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Prevalência , Medição de Risco
7.
Microvasc Res ; 80(1): 89-98, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20303995

RESUMO

OBJECTIVE: In order to perform effective translational research for cancer therapy, we need to employ pre-clinical models which reflect the clinical situation. The purpose of this study was to quantitatively compare the vascular architecture of human colorectal cancer and experimental tumour models to determine the suitability of animal models for vascular studies and antivascular therapy. METHODS: In this study we investigated the three-dimensional properties of colonic tumour vasculature in both human clinical tissues (normal mucosa control [n=20], carcinoma [n=20] and adenoma [n=6]) and murine colorectal xenografts (LS147T [n=6] and SW1222 [n=6]). Scanning Electron Microscope Stereoimaging (SEM) and X-ray Micro-Computed Tomography (Micro-CT) methods were employed for 3D analyses of the vascular corrosion casts from these tissues. RESULTS: Morphological measurements showed that there were significant differences in the underlying morphology in the different tissues. Of the studied xenografts, LS147T is more consistently similar to the vascular architecture of the human carcinoma than SW1222. The only reversal of this is for the inter-vessel distance. CONCLUSION: While SEM stereoimaging provided better surface detailed resolution of the corrosion casts, it was complimented by the fully 3D micro-CT method. Comparison made between the xenografts and clinical tumours showed that the LS147T xenografts shared many similarities with the clinical tumour vasculature. This study provides insight into how to select the most suitable pre-clinical models for translational studies of clinical cancer therapy.


Assuntos
Molde por Corrosão , Imageamento Tridimensional/métodos , Microvasos/patologia , Neoplasias/irrigação sanguínea , Microtomografia por Raio-X/métodos , Adenoma/irrigação sanguínea , Adenoma/patologia , Animais , Carcinoma/irrigação sanguínea , Carcinoma/patologia , Linhagem Celular Tumoral , Colo/anatomia & histologia , Colo/irrigação sanguínea , Colo/patologia , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/patologia , Feminino , Humanos , Mucosa Intestinal/anatomia & histologia , Mucosa Intestinal/irrigação sanguínea , Masculino , Camundongos , Camundongos Nus , Microscopia Eletrônica de Varredura/métodos , Neoplasias/patologia , Transplante Heterólogo/patologia
8.
Br J Cancer ; 101(1): 64-70, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19513074

RESUMO

BACKGROUND: Carcinoma in situ (CIS) of the testis is considered to be a precancerous germinal cell lesion, but the precise cellular and molecular mechanisms underlying transformation of CIS into invasive pluripotent cancer cells remain to be elucidated. Moreover, a satisfactory animal model for the experimental study of germinal tumours has not been developed to date. METHODS: We have developed a tumour model that involves the microinjection of green fluorescent protein-labelled embryonic stem (ES) cells (which are functionally equivalent to CIS cells) into syngenic mouse seminiferous tubules, a unique cell microenvironment in which germinal cells mature and CIS arise. To characterise the vascularisation of teratocarcinomas, which arise after cell transplant, we used immunohistochemistry, together with a qualitative and quantitative analysis of scanning electron microscopy images of corrosion casting samples. RESULTS: Embryonic stem cells transplanted into seminiferous tubules did not differentiate into germinal cells, but rather they behaved as invasive embryonal carcinoma (EC) stem cells. The vascular pattern of the experimental teratocarcinomas showed a highly disorganised architecture, and some of the neoplastic capillaries were derived, at least in part, from the original transplanted ES cells. CONCLUSION: The transplantation of pluripotent ES cells into seminiferous tubules efficiently recapitulates the early stages of development of teratocarcinomas. Consequently, this method constitutes a novel in vivo model to study the mechanisms of invasion and progression of experimental germinal tumours.


Assuntos
Células-Tronco de Carcinoma Embrionário/patologia , Células-Tronco Pluripotentes/patologia , Túbulos Seminíferos/patologia , Teratocarcinoma/irrigação sanguínea , Teratocarcinoma/patologia , Neoplasias Testiculares/irrigação sanguínea , Neoplasias Testiculares/patologia , Animais , Transformação Celular Neoplásica/patologia , Masculino , Camundongos , Neovascularização Patológica/patologia , Células-Tronco Pluripotentes/transplante , Transplante de Células-Tronco
9.
Int J Artif Organs ; 30(10): 930-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17992655

RESUMO

OBJECTIVE: External stents placed around vein grafts have demonstrated effectiveness in reducing neointimal hyperplasia by preventing distension of the thin-walled vein grafts when exposed to arterial pressure. However, the ideal stent material has yet to be defined. The following study investigates the short- and long-term effects of an innovative polyester mesh stent designed with optimized adaptation of circumferential compliance. METHODS: Following in vitro definition of the ideal macro-porous polyester stent material, a total of 12 sheep underwent implantation of bilateral carotid artery vein graft bypasses. In six sheep, the short term outcome (four weeks of implantation) was investigated by comparing the newly-designed stent to native veins, micro-porous PTFE stent grafts and metallic Biocompound stents (BCGs). Flow volume and graft diameter were measured prior to explantation. Grafts were evaluated histologically with respect to morphometry and immunoassaying. In the long-term group (6-month implantation time), the polyester stent was compared to native veins. RESULTS: All stents effectively prevented dilatation of the graft. Perfused vessel diameters of the polyester veins were 8.3+/-0.6 mm. BCG as well as PTFE veins showed diameter reduction to 7.4+/-0.7 mm (p<0.05) and 7.8+/-0.4 mm (p<0.05), respectively. Both in the short and long terms, the new polyester stent led to significantly higher reduction of neointimal hyperplasia and luminal encroachment compared to the native vessel. It proved superior to PTFE stenting, while the Biocompound material failed to prove efficacy. CONCLUSIONS: It was demonstrated that the new macro-porous polyester mesh stent reduced neointimal hyperplasia more effectively than other commercially available stents.


Assuntos
Oclusão de Enxerto Vascular/prevenção & controle , Poliésteres/uso terapêutico , Veia Safena/transplante , Stents , Telas Cirúrgicas , Animais , Implante de Prótese Vascular/métodos , Doenças das Artérias Carótidas/cirurgia , Artéria Carótida Primitiva/cirurgia , Dilatação Patológica/prevenção & controle , Modelos Animais de Doenças , Hiperplasia/prevenção & controle , Veia Safena/patologia , Ovinos , Túnica Íntima/patologia
10.
Handchir Mikrochir Plast Chir ; 37(6): 408-14, 2005 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-16388456

RESUMO

Vessel systems and the microvascular unit may be studied by a variety of morphological techniques which enable improved structure-function analyses. Two-dimensional light and electron microscopic sectioning techniques with and without specific markers are complemented by 3D vascularisation and perfusion study techniques. Static ex vivo modalities still prevail, however, the future will be dominated by intravital high-resolution techniques.


Assuntos
Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Microcirculação/anatomia & histologia , Microscopia Confocal , Microscopia Eletrônica , Retalhos Cirúrgicos/irrigação sanguínea , Animais , Molde por Corrosão , Dermoscopia , Endotélio Vascular/anatomia & histologia , Humanos , Microscopia de Fluorescência , Fluxo Sanguíneo Regional/fisiologia
11.
Handchir Mikrochir Plast Chir ; 37(6): 365-74, 2005 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-16388451

RESUMO

A regular tissue functioning requires the adequate supply of oxygen and nutrient via blood vessels. The sequences of formation and maturation of vessels are initiated and maintained by different growth factors. The VEGF growth factor plays an exceptional role in these mechanisms. The creation of sublethal ischemia as an angiogenic stimulus known as "Delay" is a well established procedure in plastic surgery, although the underlying molecular biological mechanisms still remain unknown. The important role of VEGF and its regulation depending on oxygen pressure suggest a strong connection between this growth factor and the delay phenomenon. The VEGF concentration in skin and underlying muscle was measured in overdimensioned random pattern flaps on 32 male Sprague-Dawley rats after either VEGF gene therapy or circumcision without elevation of the flap and compared to controls. Additional random pattern flaps were raised seven days post gene therapy or delay. The effect on the flap perfusion was measured postoperatively using Indocyanine green Laser Fluoroscopy and the size of the surviving and necrotic areas of the flaps were analysed. The skin of the random pattern flaps showed both in the Delay group and in the VEGF gene therapy group a significantly elevated VEGF concentration compared to the controls. The underlying rectus abdominis muscle showed no significant differences in VEGF concentration between the groups. The flap perfusion postoperatively was significantly increased solely in the VEGF gene therapy group. The analysis of the surviving area of the flaps showed a significant increase over the controls in the gene therapy group. The Delay procedure results in a significantly and locally raised concentration of the VEGF growth factor. The gene therapeutical use of this growth factor allows us to raise flap perfusion and to reduce necrosis. Both VEGF gene therapy and Delay seem to promote similar mechanisms whereas the gene therapy produced superior results in this setting.


Assuntos
Técnicas de Transferência de Genes , Terapia Genética , Neovascularização Fisiológica/genética , Retalhos Cirúrgicos/irrigação sanguínea , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Expressão Gênica/fisiologia , Masculino , Necrose , Ratos , Fluxo Sanguíneo Regional/fisiologia , Pele/irrigação sanguínea , Pele/patologia , Fatores de Tempo , Sobrevivência de Tecidos/genética
12.
Angiogenesis ; 2(3): 255-63, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-14517465

RESUMO

Microvascular corrosion casting was used for evaluating qualitatively and quantitatively angiogenesis in the chick chorioallantoic membrane (CAM). Series of CAMs from day 8 to 18 were examined. The density of plexus capillaries increases rapidly until day 10 and then remains constant. The vessels connected to the plexus (first order vessels) increase in number and length between days 10 and 12. The vessels initiating from first-order vessels (second order) also increase in number but remain nearly the same in lengths and diameters. Compared to previous studies using stereomicroscopy, significant differences in vessel numbers and lengths exist, which can be explained by the low resolution and magnification resulting in too low vascular densities of the pre- and post-capillaries. The third-order vessels increase in number until day 12 when they reach a plateau, whereas higher-order vessels increase in number. These results give an insight into the vascular development of this organ, and provide the basis for assessing the targets and effects of angiogenic or antiagiogenic agents.

13.
J Cancer Res Clin Oncol ; 116(5): 517-24, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2229144

RESUMO

This study was designed to examine the vascular system of human xenotransplanted tumors on nude mice with different complementary morphometrical and morphological methods. The vascular system shows a chaotic arrangement. There is an extreme heterogeneity in the vascular distribution and density. Large avascular regions could be identified in several non-necrotic tumors. There was no clear difference in the vascular density between the center and the periphery of the tumors, nor was there any zonal correlation for the distribution of the necrosis. With three-dimensional corrosion casts it could be demonstrated that clusters of vessels were directly beneath areas almost free of vessels. In the center, vessels often form a sinusoidal system with numerous blind ends without clearly discernible endothelial cells. Numerous irregular tumor-cell-lined sinusoids are visible next to endothelial-lined vessels with transmission electron microscopy. With scanning electron microscopy it could be demonstrated that large-calibre endotheliazed vessels were found in the direct vicinity or in the center of non-viable zones. Even large-calibre vessels have a capillary wall structure. Sometimes, a basement membrane cannot be observed at all or only incompletely. There are numerous indications of vascular discontinuities and leaks with a widespread intercellular occurrence of blood cells.


Assuntos
Vasos Sanguíneos/ultraestrutura , Melanoma/irrigação sanguínea , Sarcoma/irrigação sanguínea , Animais , Vasos Sanguíneos/patologia , Molde por Corrosão , Camundongos , Camundongos Nus , Microscopia Eletrônica , Necrose , Transplante Heterólogo
14.
Life Sci ; 75(11): 1343-56, 2004 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-15234192

RESUMO

Angiogenesis is crucial to tumor growth and metastasis, and interruption of this process is a prime avenue for therapeutic intervention of tumor proliferation. The present study has made use of the S180 tumor-bearing mouse model to investigate the polysaccharopeptide, PSP, isolated from the edible mushroom Coriolus versicolor, a herbal medicine known for its anti-angiogenesis properties. Quantitative analysis of microcorrosion casting of the tumor tissue showed more angiogenic features such as dense sinusoids and hot spots, in control (untreated) than in PSP-treated animals. Immunostaining of tumor tissues with antibody against the endothelial cell marker (Factor VIII) demonstrated a positive correlation in that both the vascular density and tumor weight were lower in mice treated with PSP. Morphometric analysis of corrosion casts revealed that, even though the total amount of new vessel production was reduced, the basic tumor type-specific vascular architecture was retained. However, the expression of vascular endothelial cell growth factor (VEGF) in these tumors was suppressed. In conclusion, anti-angiogenesis should be one of the pathways through which PSP mediated its anti-tumor activity.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Basidiomycota/química , Neovascularização Patológica/prevenção & controle , Proteoglicanas/uso terapêutico , Sarcoma Experimental/tratamento farmacológico , Administração Oral , Animais , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/ultraestrutura , Molde por Corrosão/métodos , Modelos Animais de Doenças , Ingestão de Líquidos , Técnica Indireta de Fluorescência para Anticorpo , Processamento de Imagem Assistida por Computador , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Transplante de Neoplasias , Neovascularização Patológica/metabolismo , Proteoglicanas/administração & dosagem , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sarcoma Experimental/irrigação sanguínea , Sarcoma Experimental/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo , Água
15.
Eur J Cardiothorac Surg ; 7(7): 376-82, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8373622

RESUMO

A significant proportion of early graft occlusions after aortocoronary revascularization using autologous saphenous vein grafts (SVG) are due to mechanical and/or metabolic or biochemical endothelial lesions. The morphological examination of the endothelium, usually carried out using light microscopy or by various types of scanning electron microscopy (SEM), does not give any indication of the functioning of the endothelium (E). Functionally intact E is capable of producing endothelium-derived relaxing factor (EDRF); a practicable in vitro test is the relaxation of pre-contracted vein segments (VS) in response to acetylcholine (ACh) application. To study the effect of the solution used to rinse and store the SVG between removal and implantation on the functional characteristics of the E, we performed in vitro tests on macroscopically intact VS removed from the saphenous vein of 30 male patients who underwent elective CABG surgery. Isolated VS rings were incubated for 60 min in heparinized whole blood (HWB), Bretschneider's cardioplegic solution (HTK), human albumin solution (HAS), or Ringer's solution (RS) and compared with the results obtained immediately after the removal of untreated control samples (C) taken from the same patients. After equilibration in carbogen aerated Krebs-Henseleit solution and precontraction by 3 x 10(-7) M noradrenaline (NE), relaxation induced by 10(-6) M ACh was measured. Only the samples stored in HWB (13.4 +/- 0.4 mN) showed similar maximal contractions with NE to those in the control group (14.4 +/- 0.5 mN), i.e. all those segments which showed both contractions with NE and relaxation with ACh.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Soluções Cardioplégicas , Ponte de Artéria Coronária , Endotélio Vascular/patologia , Veia Safena/patologia , Veia Safena/transplante , Acetilcolina , Adulto , Idoso , Albuminas , Endotélio Vascular/metabolismo , Endotélio Vascular/ultraestrutura , Glucose , Heparina , Humanos , Soluções Isotônicas , Masculino , Manitol , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Óxido Nítrico/biossíntese , Norepinefrina , Preservação de Órgãos/métodos , Cloreto de Potássio , Procaína , Solução de Ringer , Trometamina
16.
Rofo ; 174(5): 579-87, 2002 May.
Artigo em Alemão | MEDLINE | ID: mdl-11997857

RESUMO

PURPOSE: Characterization of the endoluminal surface of a modular stent graft and correlation of macropathological findings with results of radiological methods. METHODS: Aneurysms of the infrarenal aorta were created in 36 mongrel FBI dogs using autologous material. Endovascular treatment was performed with modular stent grafts using two polyester-covered nitinol stents connected with overlap within the aneurysm. Follow-up was 1 and 6 weeks, and 6 months for 12 animals, respectively. Results were documented using sonography, intravascular ultrasound (IVUS), spiral CT, MRI, and digital subtraction angiography (DSA). After fixation, the aorta was prepared and incised lengthwise. Before histopathological work-up, the different segments were macropathologically characterized and correlated with the respective findings of the radiological methods. RESULTS: 4 cases showed high grade stenosis within the stent grafts and graft occlusion occurred in two cases. The connection sites of these modular stent grafts showed steps and partial separation of the graft components was causative in 5 of these cases. Migration of graft components occurred in three cases, one of them with complete disconnection of the modular device. Irregulartities and deposits on the endoluminal surface were systematically underestimated with all radiological techniques used. IVUS showed moderate concordance concerning deployment and unfolding of the stent graft, however, irregularities of the endoluminal surface were systematically underestimated. Concordance of MRI, sonography, and CT was worse. Contrast-enhanced T1-w MRI detected endoluminal deposits with moderate concordance. However, the thickness of deposits was underestimated. DSA, IVUS, and CT showed only poor concordance with macropathological findings. CONCLUSIONS: The connection site of modular stent grafts predisposes to stenosis, occlusion, and disconnection of the modular device. Stent deployment and unfolding of the membrane might be examined with IVUS. MRI is useful for detecting endoluminal deposits and stenosis. However, radiological methods will underrate irregularities and deposits of the endoluminal surface.


Assuntos
Aneurisma da Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/patologia , Stents , Animais , Aneurisma da Aorta Abdominal/cirurgia , Modelos Animais de Doenças , Cães , Humanos , Desenho de Prótese , Radiografia , Resultado do Tratamento
17.
Hernia ; 8(3): 233-41, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15098100

RESUMO

BACKGROUND: The stability of the lower abdominal wall may play a considerable role in the development of inguinal hernia. Therefore, the strength of the individual wall layers needs to be quantified. Despite numerous advances in hernia repair, comparatively few systematic biomechanic and morphometric analyses have been performed. Our aim was to establish and apply a standardised procedure for testing the abdominal wall layers' stability. METHODS: After dissecting the abdominal walls of 16 cadavers into separate layers, we used a spherical punch and a force transducer to investigate the forces necessary to foraminate the layer. In addition, maximum tensile-strength and suction tests and histologic morphometry were performed. RESULTS: The transversalis fascia was torn up on an average of 10.5 N, the peritoneum including pre- and subperitoneal tissue on 46.6 N, the aponeurosis of obliquus internus abdominis muscle on 51.7 N, and the aponeurosis of obliquus externus abdominis muscle on 92.6 N. Tensile tests of tissue strips obtained from defined areas showed comparable results. In contrast, surgical mesh revealed values between 60 and 150 N in punching tests. Left-right comparisons, as well as comparisons of the individual areas, revealed considerable intra- and inter-individual differences. CONCLUSIONS: Biological hernia repair should focus on a reinforcement of the tissue layers with the highest biomechanic stability. Reinforcement of the transversal fascia must be questioned according to our results of poor mechanical resistance.


Assuntos
Parede Abdominal/fisiologia , Fenômenos Biomecânicos , Hérnia Inguinal/cirurgia , Canal Inguinal/fisiologia , Parede Abdominal/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Cadáver , Feminino , Humanos , Imuno-Histoquímica , Canal Inguinal/patologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Estresse Mecânico , Telas Cirúrgicas , Resistência à Tração
18.
Plast Reconstr Surg ; 99(3): 705-10; discussion 711-2, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9047190

RESUMO

This study was designed to clarify the vascularization of the inner anterior abdominal wall with respect to the novel transversus and rectus abdominis musculoperitoneal (TRAMP) flap, which was introduced recently for vaginal reconstruction. A series of human cadavers was injected with a lead oxide-gelatine mixture by means of the deep inferior epigastric artery and subsequently dissected and examined by radiography. In all cases we found that the blood supply of the entire rectus abdominis muscle from the symphysis to the costal arch and that of the medial 10 to 15 cm of the transversus abdominis muscle, as well as the underlying peritoneum, was provided by several branches of the deep inferior epigastric artery. "Choke" arteries to the superior epigastric artery and also to the intercostal arteries (X, XI, and XII) have been shown to be common features. From the anatomic point of view, these observations offer the possibility of mobilizing large parts of the transversus abdominis muscle together with the rectus abdominis muscle for reconstructive surgery.


Assuntos
Músculos Abdominais/irrigação sanguínea , Artérias Epigástricas/anatomia & histologia , Retalhos Cirúrgicos , Vagina/cirurgia , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Humanos , Pessoa de Meia-Idade , Retalhos Cirúrgicos/irrigação sanguínea
19.
Med Eng Phys ; 34(7): 806-16, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21992970

RESUMO

BACKGROUND: An ideal prosthetic mesh for incisional hernia repair should mimic the anisotropic compliance of the abdominal wall, and at lower loads should exhibit higher distensibility without impairment of safety at higher loads. This study evaluated the biomechanical properties of six meshes in a rabbit model. METHODS: New Zealand white rabbits were used for this study. Two meshes of the same brand (Ethicon Physiomesh™, Bard Composix(®) L/P, Gore Dualmesh(®), Bard Sepramesh(®), Ethicon Proceed(®) or Parietex™ Composite) were implanted into each animal for assessment of intra-abdominal hernia repair, with a total of ten meshes per group. Twelve weeks after implantation, the abdominal walls with ingrown meshes were harvested and examined biomechanically with a plunger test. The mesh-tissue compliance was evaluated by the forces exerted at given displacements and also described through a simple mathematical approximation. Abdominal wall samples were collected for histopathology, cell turnover and morphometry. RESULTS: No mesh-related complications were seen. The adhesion score was significantly higher in Bard Composix(®) L/P and Ethicon Proceed(®) meshes. Significant shrinkage was seen in Gore Dualmesh(®) and Parietex™ Composite meshes. Physiomesh™ exhibited the highest compliance during plunger testing, characterized by lower, more physiological reaction forces against tissue displacement than the competitor meshes. In contrast, the safety modulus was comparable in all groups. Histology showed less collagen and less foreign body reaction in the Physiomesh™ samples contributing to patient's comfort. CONCLUSION: In terms of safety, this study showed no superiority of any single mesh. The comfort modulus however differed, being lowest in the newly developed Physiomesh™.


Assuntos
Parede Abdominal/patologia , Herniorrafia/instrumentação , Fenômenos Mecânicos , Cavidade Peritoneal , Próteses e Implantes , Parede Abdominal/fisiopatologia , Adesivos/química , Animais , Fenômenos Biomecânicos , Dioxanos/química , Feminino , Teste de Materiais , Cavidade Peritoneal/cirurgia , Polidioxanona/química , Poliésteres/química , Polipropilenos/química , Porosidade , Coelhos , Cicatrização
20.
Injury ; 43(6): 903-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22342075

RESUMO

The aim of this experimental cadaver study was to investigate which kinds of lesions could occur in jam events between the glass and seal entry of power-operated motor vehicle side door windows at two different closing forces. Ten hands of fresh cadaver specimens were used. Three different hand positions chosen to simulate real events in which a finger is jammed between the glass and seal entry of the window of a current motor vehicle were examined. The index, middle, ring, and little finger of each hand were separately jammed both at the proximal and distal interphalangeal joint at closing forces of 300 and 500 N with a constant window glass closing speed of 10 cm/s. Macroscopically visible injuries were documented and radiographs of all fingers were obtained in two standard planes. At a closing force of 300 N, contusion marks of the skin, palmar joint instabilities and superficial skin lesions occurred, whilst at 500 N superficial skin lesions, superficial and deep open crush injuries, and fractures were observed. The results of this study experimentally demonstrate the kinds of finger injuries that could be expected in real jam events between the glass and seal entry in automatic power-operated windows.


Assuntos
Traumatismos dos Dedos/diagnóstico por imagem , Articulações dos Dedos/diagnóstico por imagem , Fraturas Ósseas/diagnóstico por imagem , Idoso de 80 Anos ou mais , Cadáver , Feminino , Traumatismos dos Dedos/patologia , Articulações dos Dedos/patologia , Fraturas Ósseas/patologia , Humanos , Modelos Teóricos , Veículos Automotores , Radiografia
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