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1.
NPJ Microgravity ; 9(1): 70, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37673938

RESUMO

X-ray radioscopy enables the in-situ monitoring of metal alloy processes and then gives access to crucial information on the dynamics of the underlying phenomena. In the last decade, the utilisation of this powerful imaging technique has been adapted to microgravity platforms such as sounding rockets and parabolic flights. The combination of microgravity experimentation with X-ray radioscopy has resulted in a leap in the understanding of fundamental science and has opened new paths in the fields of materials science. The present review focuses on the short history of this research, which includes facility developments, microgravity experiments and results obtained by partners of the XRMON (In-situ X-Ray MONitoring of advanced metallurgical processes under microgravity and terrestrial conditions) research project in the framework of the MAP (Microgravity Application Promotion) programme of the European Space Agency. Three illustrative research topics that were advanced significantly through the use of X-ray radioscopy will be detailed: solidification of metal alloys, metallic foam formation and diffusion in melts.

2.
Hernia ; 24(6): 1159-1173, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32388587

RESUMO

PURPOSE: Synthetic prosthetic materials that are fully absorbable seek to reduce the host foreign body reaction and promote host tissue regeneration. This preclinical trial was designed to analyse, in the long term, the behaviour of two prosthetic meshes, one synthetic and one composed of porcine collagen, in abdominal wall reconstruction. METHODS: Partial defects were created in the abdominal walls of New Zealand rabbits and repaired using a synthetic absorbable mesh (Phasix™) or a non-crosslinked collagen bioprosthesis (Protexa™). After 3, 6, 12 and 18 months, specimens were recovered for light microscopy and collagen expression analysis to examine new host tissue incorporation, macrophage response and biomechanical strength. RESULTS: Both materials showed good host tissue incorporation in line with their spatial structure. At 18 months postimplant, Protexa™ was highly reabsorbed while the biodegradation of Phasix™ was still incomplete. Collagenization of both materials was good. Macrophage counts steadily decreased over time in response to Phasix™, yet persisted in the collagen meshes. At 18 months, zones of loose tissue were observed at the implant site in the absence of herniation in both implant types. The stress-stretch behaviour of Phasix™ implants decreased over time, being more pronounced during the period of 12-18 months. Nevertheless, the abdominal wall repaired with Protexa™ became stiffer over time. CONCLUSION: Eighteen months after the implant both materials showed good compatibility but the biodegradation of Phasix™ and Protexa™ was incomplete. No signs of hernia were observed at 18 months with the stress-stretch relations being similar for both implants, regardless of the more compliant abdominal wall repaired with Protexa™ at short term.


Assuntos
Parede Abdominal/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Telas Cirúrgicas/normas , Animais , Modelos Animais de Doenças , Coelhos
3.
Hernia ; 23(4): 789-800, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30806886

RESUMO

PURPOSE: Biomaterials with an antimicrobial coating could avoid mesh-associated infection following hernia repair. This study assesses the use of a chlorhexidine-loaded carboxymethylcellulose gel in a model of Staphylococcus aureus mesh infection. METHODS: A 1% carboxymethylcellulose gel containing 0.05% chlorhexidine was prepared and tested in vitro and in vivo. The in vitro tests were antibacterial activity (S. aureus; agar diffusion test) and gel cytotoxicity compared to aqueous 0.05% chlorhexidine (fibroblasts; alamarBlue). For the in vivo study, partial abdominal wall defects (5 × 2 cm) were created in New Zealand white rabbits (n = 15) and inoculated with 0.25 mL of S. aureus (106 CFU/mL). Defects were repaired with a lightweight polypropylene mesh (Optilene) without coating (n = 3) or coated with a carboxymethylcellulose gel (n = 6) or chlorhexidine-loaded carboxymethylcellulose gel (n = 6). Fourteen days after surgery, bacterial adhesion to the implant (sonication, immunohistochemistry), host tissue incorporation (light microscopy) and macrophage reaction (immunohistochemistry) were examined. RESULTS: Carboxymethylcellulose significantly reduced the toxicity of chlorhexidine (p < 0.001) without limiting its antibacterial activity. While control and gel-coated implants were intensely contaminated, the chlorhexidine-gel-coated meshes showed a bacteria-free surface, and only one specimen showed infection signs. The macrophage reaction in this last group was reduced compared to the control (p < 0.05) and gel groups. CONCLUSIONS: When incorporated in the carboxymethylcellulose gel, chlorhexidine showed reduced toxicity yet maintained its bactericidal effect at the surgery site. Our findings suggest that this antibacterial gel-coated polypropylene meshes for hernia repair prevent bacterial adhesion to the mesh surface and have no detrimental effects on wound repair.


Assuntos
Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Carboximetilcelulose Sódica/uso terapêutico , Clorexidina/uso terapêutico , Herniorrafia/métodos , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Telas Cirúrgicas , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Materiais Biocompatíveis , Carboximetilcelulose Sódica/farmacologia , Clorexidina/farmacologia , Fibroblastos/efeitos dos fármacos , Géis/uso terapêutico , Coelhos , Telas Cirúrgicas/microbiologia
4.
Hernia ; 21(2): 291-298, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27023877

RESUMO

PURPOSE: The application of mesh-reinforced hiatal closure has resulted in a significant reduction in recurrence rates in comparison with primary suture repair. However, the use of meshes has not completely extended in all the cases of large paraesophageal hiatal hernias (LPHH) due to the complications related to them. The aim of this study is to present our long-term results and complications related to Crurasoft® mesh (Bard) for the treatment of LPHH. METHODS: From January 2004 to December 2014, 536 consecutive patients underwent open or laparoscopic fundoplication for gastroesophageal reflux disease or LPHH at Ramón y Cajal University Hospital. Primary simple suture of the crura and additional reinforcement with a Crurasoft® mesh (Bard) was performed in 93 patients (17.35 %). Radiologic hiatal hernia recurrence and mesh-related complications were investigated. RESULTS: Of the 93 patients undergoing mesh repair, there were 28 male and 65 female with a mean age of 67.27 years (range 22-87 years). Laparoscopic surgery was attended in 88.2 % of the cases, and open surgery in the rest 11.8 %. Mean operative time was 167.05 min (range 90-370 min). Median postoperative stay was 4.79 days (range 1-41 days). Conversion rate was 8.53 % (7 patients). Intraoperative complications were described in 10.75 % (10 patients), but all of them, except in one case, could be managed laparoscopically. Overall postoperative complications rate was 28 %. Early postoperative complications occurred in 11 patients (12 %), respectively, for grades 2 (6 cases), 3b (1 case) and 5 (4 cases) according to the Clavien-Dindo classification. Late postoperative complications occurred in 15 patients (16 %), respectively, for grades 1 (7 cases), 2 (2 cases), 3b (5 cases) and 5 (1 case) according to the Clavien-Dindo classification. Thirty day-mortality rate was 4.3 %. Mortality rate specific associated with the mesh was 1 %. Reoperation rate was 5.4 %. After a median follow-up of 76.33 months (range 3-130 months), 8 patients (9 %) developed a recurrent hiatal hernia. Mesh was removed in three cases (3.22 %). CONCLUSIONS: In our experience, the recurrence rate in patients with a Crurasoft® (Bard) is acceptable. However, the rate of postoperative complications and mortality is excessive. The use of meshes in the hiatus keeps on being controversial due to the severe complications related to them. It would be advisable to compare our results in the non-mesh group in terms of recurrences and complications, to determine if meshes in the hiatus should be given in these patients due to its high rate of complications.


Assuntos
Fundoplicatura/efeitos adversos , Refluxo Gastroesofágico/cirurgia , Hérnia Hiatal/cirurgia , Telas Cirúrgicas/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Refluxo Gastroesofágico/diagnóstico por imagem , Hérnia Hiatal/diagnóstico por imagem , Humanos , Laparoscopia/efeitos adversos , Masculino , Pessoa de Meia-Idade , Recidiva , Reoperação , Estudos Retrospectivos , Técnicas de Sutura , Adulto Jovem
5.
Rev. esp. investig. quir ; 20(4): 117-118, 2017. ilus
Artigo em Espanhol | IBECS | ID: ibc-172289

RESUMO

En un paciente de diecinueve años de edad intervenido por apendicitis aguda se localizó un adenoma serrado con displasia de bajo grado en la pieza quirúrgica. Dichas lesiones son infrecuentes, pero pueden ir asociadas a cáncer colorrectal y síndromes de poliposis serrada, a través de la "vía serrada de la carcinogénesis". La evidencia actualmente disponible sugiere que los pólipos serrados apendiculares pueden tener ligeras diferencias con respecto a sus análogos colorrectales. Sin embargo, se mantienen las recomendaciones para dichos pólipos, que recomiendan su extirpación completa en caso de objetivarse displasia, y la realización de colonoscopia de seguimiento


A serrated adenoma with low grade dysplasia was founded in the appendectomy specimen of a nineteen year old male intervened due to acute appendicitis. These lesions are infrequent, but might be associated with colorectal cancer and a serrated polyposis syndrome thought the "serrated pathway of carcinogenesis". Actual evidence suggests that serrated polyps found in the appendix can differ from their colorrectal analogues. However, the same recommendations are regarded, and they should be completely removed when showing dysplasia, and be followed with routinely colonoscopy


Assuntos
Humanos , Masculino , Adulto Jovem , Adenoma/diagnóstico , Apêndice/patologia , Apendicite/diagnóstico , Polipose Adenomatosa do Colo , Neoplasias Colorretais , Apendicite/cirurgia , Adenoma/cirurgia
6.
Hernia ; 20(6): 869-878, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27590327

RESUMO

PURPOSE: This study assesses the use of an absorbable polymer loaded with chlorhexidine (CHX) as an antibacterial coating for polypropylene (PP) meshes employed in hernia repair. METHODS: The polymer N,N-dimethyl-N-benzyl-N-(2-methacryloyloxyethyl) ammonium bromide was loaded with CHX (1 % w/w). Fragments (1 cm2) of Optilene® Mesh Elastic were coated either with the unloaded (POL) or CHX-loaded polymer (POL-CHX). Uncoated fragments (PP) served as controls. The release kinetics of the POL-CHX coating was monitored by HPLC. Sterile fragments were placed on agar plates previously contaminated with 106 CFU of Staphylococcus aureus (Sa) ATCC25923, Staphylococcus epidermidis (Se) ATCC12228, or Escherichia coli (Ec) ATCC25922 and incubated at 37 °C for 1/2/7 days. At each time point, inhibition halos were measured and bacterial adhesion to the meshes quantified by sonication and scanning electron microscopy. Coating cytotoxic effects were examined on cultured fibroblasts. RESULTS: The polymer coating gradually released CHX over 3 days. Inhibition halos were produced only around the POL-CHX-coated meshes and these were significantly smaller for Ec than Sa or Se (p < 0.01). While POL-CHX prevented bacterial adhesion to the mesh, the reduced bacterial yields over time were observed for the POL-coated versus control PP meshes (p < 0.001). By day 7, only Ec remained attached to the surface of control meshes. The POL coating was not cytotoxic, yet POL-CHX reduced the viability of cultured fibroblasts. CONCLUSIONS: When loaded with the antiseptic CHX, this quaternary ammonium-based polymer coating released its contents in a controlled manner indicating its potential prophylactic use to reduce the risk of infection following PP mesh implantation.


Assuntos
Antibacterianos/administração & dosagem , Clorexidina/administração & dosagem , Herniorrafia/métodos , Infecções Relacionadas à Prótese/prevenção & controle , Telas Cirúrgicas , Implantes Absorvíveis , Anti-Infecciosos Locais/administração & dosagem , Aderência Bacteriana/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Escherichia coli/efeitos dos fármacos , Herniorrafia/instrumentação , Técnicas In Vitro , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Polímeros , Polipropilenos/administração & dosagem , Infecções Relacionadas à Prótese/etiologia , Compostos de Amônio Quaternário/administração & dosagem , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia , Telas Cirúrgicas/microbiologia
7.
Rev. esp. investig. quir ; 18(1): 38-42, 2015. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-137257

RESUMO

Los tumores desmoides aparecen como resultado de la proliferación fibroblástica, sin signos histológicos de malignidad pero localmente muy agresivos. Se han descrito casos de fibromatosis tras extirpación de GIST. Presentamos el caso de un GIST gástrico operado, que a los 18 meses se realiza laparotomía exploradora por sospecha de recurrencia y tras hallazgos histológicos definitivos, se diagnostica de fibromatosis intra-abdominal agresiva. Se discute la valoración clínico-oncológica de la fibromatosis como forma de recurrencia local del GIST


Desmoid tumors appear as a result of fibroblastic proliferation without histological signs of malignancy but locally aggressive. Fibromatosis have been described after removing a gastrointestinal stromal tumor (GIST). We present a case of a resected gastric GIST and eigthteen months after surgery, a exploratory laparotomy was performed suspecting recurrence and after definitive histological findings, the diagnosis was aggressive intra-abdominal fibromatosis. Clinical-oncological assessment of fibromatosis is discussed as a form of GIST local recurrence


Assuntos
Feminino , Humanos , Fibromatose Agressiva/induzido quimicamente , Fibromatose Abdominal/induzido quimicamente , Fibromatose Abdominal/metabolismo , Carcinoma/metabolismo , Carcinoma/patologia , Doenças Peritoneais/metabolismo , Tomografia Computadorizada Espiral/instrumentação , Fibromatose Agressiva/metabolismo , Fibromatose Agressiva/patologia , Fibromatose Abdominal/complicações , Fibromatose Abdominal/diagnóstico , Carcinoma/complicações , Carcinoma/enfermagem , Doenças Peritoneais/diagnóstico , Tomografia Computadorizada Espiral/métodos
8.
Surg Endosc ; 28(12): 3479-88, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24969850

RESUMO

INTRODUCTION: The most common treatment option for ventral and umbilical hernias is the implant of a prosthetic mesh. This study compares the behaviour of a new mesh, Parietex™ Composite Ventral Patch (Ptx), with two commercially available meshes, Ventralex™ ST Hernia Patch and Proceed™ Ventral Patch. MATERIALS AND METHODS: The following meshes were tested in a umbilical-hernia repair model using 54 rabbits: Ventralex™ ST Hernia Patch (Vent) (Bard Davol Inc., USA); Proceed™ Ventral Patch (PVP) (Ethicon, USA) and Ptx (Covidien, Sofradim, France) (n = 18 each). At 3, 7 and 14 days postimplantation, peritoneal behaviour and adhesion formation were assessed by sequential laparoscopy. Adhesions were scored for consistency and quantified by image analysis. The animals were euthanized at 2 (n = 27) and 6 weeks (n = 27) postsurgery. Mesothelial cover of meshes and tissue ingrowth were determined by scanning and light microscopy. RESULTS: Seroma was observed in 1/18 Vent, 7/18 PVP and 4/18 Ptx, mainly between the implant and subcutaneous tissue. Firm omental adhesions between the mesh and parietal peritoneum were noted in 2/9 Vent, 6/9 PVP and 3/9 Ptx at 2 weeks and in 3/9 Vent, 5/9 PVP and 1/9 Ptx at 6 weeks. Three (out of 9) encapsulated PVP implants showed "tissue-integrated" adhesions affecting the intestinal loops. No differences between implants were detected in the surface area occupied by adhesions at 2 weeks, though at 6 weeks, percentages were significantly higher (p < 0.01; Mann-Whitney U test) for PVP compared to Ptx or Vent. At this time point, Ptx and Vent showed good host tissue incorporation and optimal mesothelialization. CONCLUSIONS: The PVP implants showed greater adhesion formation than the other materials. Postimplantation behaviour was comparable for Ptx and Vent including scarce adhesion formation and optimal mesothelialization. Regarding tissue integration, Ptx showed greater long-term collagenization of the neoformed tissue.


Assuntos
Hérnia Umbilical/cirurgia , Hérnia Ventral/cirurgia , Herniorrafia/métodos , Laparoscopia/métodos , Polipropilenos , Telas Cirúrgicas , Animais , Modelos Animais de Doenças , Masculino , Desenho de Prótese , Coelhos
9.
Soft Matter ; 10(36): 6955-62, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-24819033

RESUMO

Complex liquid structures such as metallic foams were produced in a furnace that allowed in situ X-ray monitoring of the evolution of the structure and distribution of the liquid in the foam. The experiments were carried out during parabolic flights which provided varying levels of gravity. The evolution of the characteristic liquid fraction profiles due to gravity induced drainage was measured and analysed in terms of the foam drainage equation, obtaining viscosity and surface tension by fitting solutions of the equation to the experimental data. The surface tension of the melt in the foam was decreased up to 40%. Effective viscosities of up to 139 times the viscosity of a pure bulk melt were observed. These effects could be attributed to the smaller influence of solid particles dispersed in the melt and the larger influence of the complex foam structure.

10.
Soft Matter ; 10(26): 4711-6, 2014 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-24854899

RESUMO

The present study is based on the idea of understanding the rupture of films in metal foams by studying free standing metallic films as a model system. Liquid dynamics, the velocity of the rupturing material as well as the behaviour of ceramic particles inside the melt were analysed optically ex situ and by synchrotron X-ray radiography in situ. It was found that the resistance of films to rupture is mainly based on the interaction between solid particles and an immobile oxide skin, the formation of which depends on the oxygen content of the surrounding atmosphere and the presence of magnesium.

11.
J Synchrotron Radiat ; 20(Pt 5): 809-10, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23955047

RESUMO

A set-up for simultaneous imaging and diffraction that yields radiograms with up to 200 frames per second and 5.6 µm effective pixel size is presented. Tomograms and diffractograms are acquired together in 10 s. Two examples illustrate the attractiveness of combining these methods at the EDDI beamline for in situ studies.

12.
Med. intensiva (Madr., Ed. impr.) ; 35(1): 13-21, ene.-feb. 2011. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-97239

RESUMO

Objetivo Comprobar que el marcapasos diafragmático es una forma de soporte respiratorio que puede usarse para facilitar la retirada del respirador volumétrico en pacientes con lesión medular cervical y parálisis diafragmática, mediante su comparación con el respirador volumétrico tradicional. Diseño Análisis retrospectivo de una base de datos prospectiva y de tipo caso-control apareado por edad. Ámbito Unidad de Cuidados Intensivos y Unidad de Cuidados Intermedios Respiratorios del Hospital Nacional de Parapléjicos de Toledo. Pacientes Se han recogido los datos de todos los pacientes dados de alta del hospital con soporte respiratorio permanente mediante respirador volumétrico o marcapasos diafragmático con un periodo de seguimiento de 25 años y se han realizado entrevistas personales para valorar la calidad de vida relacionada con la salud. Para las comparaciones estadísticas se han usado tests de comparaciones y de supervivencia. Intervenciones Cuestionario de calidad de vida. Variables de interés Datos demográficos y clínicos, estancia hospitalaria, mortalidad, readaptación familiar y calidad de vida relacionada con la salud. Resultados Hemos examinado las historias clínicas de 101 pacientes, 37 con marcapasos y 64 con un respirador volumétrico. Nuestros resultados muestran tanto una duración del ingreso en UCI y de la hospitalización como una reintegración familiar sin diferencias significativas, con tendencia a una mayor supervivencia en los pacientes con marcapasos (18,18 frente a 9,67 años por el método de Kaplan-Meier, p<0,001), aunque esta diferencia deja de ser estadísticamente significativa (p=0,06) tras controlar (..) (AU)


Objective To verify that the diaphragmatic pacemaker is a form of respiratory support that can be used to replace a volumetric respirator in cervical spinal injury patients with cervical spinal lesion and diaphragmatic paralysis by means of its comparison with the traditional volumetric respirator. Design Retrospective study of a prospective database and age-matched case-control study. Setting Intensive Care Unit and Intermediate Care Respiratory Unit, Paraplegics National Hospital, Toledo (Spain).Patients We collected data on all patients discharged from the Hospital with permanent respiratory support by volumetric respirator or diaphragmatic pacemaker during a follow-up period of 25 years. Personal interviews were conducted to evaluate health-related quality of life. Comparison and survival tests were used for statistical comparisons. Interventions Quality of life questionnaire. Main variables The main variables collected were demographic data, hospital stay, mortality, family reintegration and health-related quality of life. Results We evaluated the clinical records of 101 patients, 37 in the pacemaker-group and 64 in the volumetric respirator-group. Our results show that ICU admission duration and hospitalization as well as family reintegration, without significant differences, with a tendency to greater survival in pacemaker patients (18.18 versus 9.67 years by the Kaplan-Meier method, p<0.001). However, this difference becomes non-significant (p=0.06) after adjustment of the groups by age. Furthermore, better quality of life was found in these same patients with pacemakers in terms of security, communication, sociability, comfort and mobility in the patients. Conclusions Diaphragmatic pacemaker ventilation is an effective alternative to mechanical ventilation with similar efficacy that improve quality of life in patients with severe respiratory failure due to cervical spinal cord injury (AU)


Assuntos
Humanos , Paralisia Respiratória/terapia , Respiração Artificial/métodos , Marca-Passo Artificial , Traumatismos da Medula Espinal/complicações , Estudos Retrospectivos , Qualidade de Vida , Paraplegia/terapia
13.
Med Intensiva ; 35(1): 13-21, 2011.
Artigo em Espanhol | MEDLINE | ID: mdl-21232823

RESUMO

OBJECTIVE: To verify that the diaphragmatic pacemaker is a form of respiratory support that can be used to replace a volumetric respirator in cervical spinal injury patients with cervical spinal lesion and diaphragmatic paralysis by means of its comparison with the traditional volumetric respirator. DESIGN: Retrospective study of a prospective database and age-matched case-control study. SETTING: Intensive Care Unit and Intermediate Care Respiratory Unit, Paraplegics National Hospital, Toledo (Spain). PATIENTS: We collected data on all patients discharged from the Hospital with permanent respiratory support by volumetric respirator or diaphragmatic pacemaker during a follow-up period of 25 years. Personal interviews were conducted to evaluate health-related quality of life. Comparison and survival tests were used for statistical comparisons. INTERVENTIONS: Quality of life questionnaire. MAIN VARIABLES: The main variables collected were demographic data, hospital stay, mortality, family reintegration and health-related quality of life. RESULTS: We evaluated the clinical records of 101 patients, 37 in the pacemaker-group and 64 in the volumetric respirator-group. Our results show that ICU admission duration and hospitalization as well as family reintegration, without significant differences, with a tendency to greater survival in pacemaker patients (18.18 versus 9.67 years by the Kaplan-Meier method, p<0.001). However, this difference becomes non-significant (p=0.06) after adjustment of the groups by age. Furthermore, better quality of life was found in these same patients with pacemakers in terms of security, communication, sociability, comfort and mobility in the patients. CONCLUSIONS: Diaphragmatic pacemaker ventilation is an effective alternative to mechanical ventilation with similar efficacy that improve quality of life in patients with severe respiratory failure due to cervical spinal cord injury.


Assuntos
Vértebras Cervicais/lesões , Diafragma , Respiração Artificial , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Inquéritos e Questionários , Adulto Jovem
14.
Appl Environ Microbiol ; 77(4): 1524-7, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21169427

RESUMO

The presence of Cryptosporidium and Giardia in 221 fecal samples from different species of Antarctic pinnipeds was investigated by immunofluorescence microscopy and PCR. Cryptosporidium, a skunk-like genotype, was detected only in a southern elephant seal. Giardia was not detected. This is the first report of a Cryptosporidium sp. in Antarctic marine mammals.


Assuntos
Cryptosporidium/isolamento & purificação , Giardia/isolamento & purificação , Focas Verdadeiras/microbiologia , Animais , Regiões Antárticas , Cryptosporidium/classificação , Cryptosporidium/genética , Fezes/microbiologia , Imunofluorescência , Microscopia de Fluorescência , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
15.
J Xray Sci Technol ; 18(4): 429-41, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21045279

RESUMO

Time-resolved imaging with penetrating radiation has an outstanding scientific value but its realisation requires a high density of photons as well as corresponding fast X-ray image detection schemes. Bending magnets and insertion devices of third generation synchrotron light sources offer a polychromatic photon flux density which is high enough to perform hard X-ray imaging with a spatio-temporal resolution up to the µm-µs range. Existing indirect X-ray image detectors commonly used at synchrotron light sources can be adapted for fast image acquisition by employing CMOS-based digital high speed cameras already available on the market. Selected applications from life sciences and materials research underline the high potential of this high-speed hard X-ray microimaging approach.


Assuntos
Radiografia/métodos , Síncrotrons , Radiografia/instrumentação , Gravação em Vídeo
16.
Clin. transl. oncol. (Print) ; 12(9): 643-645, sept. 2010. ilus
Artigo em Inglês | IBECS | ID: ibc-124311

RESUMO

Metastasis of uterine leiomyosarcoma to the pancreas is rare. A 46-year-old woman was diagnosed with uterine leiomyosarcoma and underwent surgery. Thereafter, recurrences in the lung and subsequently in the pancreas were diagnosed. These lesions were resected and diagnosed as metastasis of uterine leiomyosarcoma. We report a rare case of uterine leiomyosarcoma with metastasis to the lung and pancreas, both of which were resected using aggressive surgery (AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Leiomiossarcoma/radioterapia , Leiomiossarcoma/secundário , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Neoplasias Pancreáticas/secundário , Neoplasias Pancreáticas/cirurgia , Neoplasias Uterinas/patologia , Neoplasias Uterinas/radioterapia , Pancreaticoduodenectomia/instrumentação , Pancreaticoduodenectomia , Leiomiossarcoma/patologia , Leiomiossarcoma/cirurgia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Neoplasias Uterinas/cirurgia , Útero/patologia
17.
Rev Sci Instrum ; 81(5): 056104, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20515181

RESUMO

A x-ray radioscopy technique for measuring in situ chemical diffusion coefficients in metallic melts is presented. The long-capillary diffusion measurement method is combined with imaging techniques using microfocus tubes and flat panel detectors in order to visualize and quantitatively analyze diffusive mixing of two melts of different chemical composition. The interdiffusion coefficient as function of temperature and time is obtained by applying Fick's diffusion laws. Tracking the time dependence of the mean square penetration depth of the mixing process allows to detect changes in the mass transport caused by convective flow. The possibility to sort out convective mass transport contributions from analysis enhances significantly the accuracy compared to the conventional long-capillary diffusion measurement method with postmortem analysis. The performance of this novel diffusion measurement method with x-ray radiography technique is demonstrated by a diffusion experiment in an Al-Ni melt.

18.
J Synchrotron Radiat ; 16(Pt 3): 432-4, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19395811

RESUMO

Investigations of pore coalescence and individual cell wall collapse in an expanding liquid metal foam by means of X-ray radioscopy with spatio-temporal micro-resolution are reported. By using white synchrotron radiation for imaging, the rupture of a film and the subsequent merger of two neighbouring bubbles could be recorded with a time sampling rate of 40000 frames s(-1) (25 micros exposure time) and a spatial sampling rate of 20 microm. The rupture time of a cell wall was found to be in the range of 300 micros. This value is in agreement with theoretical considerations which assume an inertia-dominated rupture time of cell walls in liquid metal foams.


Assuntos
Gases/química , Teste de Materiais/métodos , Metais/química , Síncrotrons , Porosidade , Soluções/química , Espectrometria por Raios X
19.
Phys Chem Chem Phys ; 9(48): 6415-25, 2007 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-18060172

RESUMO

In the present paper the authors studied isolated metallic films made from the same material used for making metallic foams, and then characterised their properties. Metal films were made from a liquid aluminium alloy reinforced with ceramic particles of known concentration. Melts without such particles were also investigated. It is shown that stable films could not be made from Al-Si alloy having no particles, and just extremely thin and fragile films could be made from commercially-pure Al. In contrast, aluminium alloys containing particles such as SiC and TiB(2) allowed pulling thin, stable films, which did not rupture. Significant thinning of films was observed when the particle concentration in the melt decreased. By in situ X-ray monitoring of liquid films during pulling, film thickness and drainage effects within the liquid film could be studied. The morphology and microstructure of films was characterised after solidification. Our work shows that the question of how foams are stabilised can be studied using a simplified system such as a film, instead of having to deal with the multitude of different structural elements present in a foam.


Assuntos
Alumínio/química , Membranas Artificiais , Ligas/química , Compostos de Boro/química , Compostos Inorgânicos de Carbono/química , Tamanho da Partícula , Compostos de Silício/química , Propriedades de Superfície , Titânio/química , Raios X
20.
Tech Coloproctol ; 11(2): 128-34, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17510743

RESUMO

BACKGROUND: Treatment of benign rectovaginal fistula has a high failure rate and entails difficult decisions. The purpose of this retrospective study was to clarify the concepts which may improve its management. METHODS: Between 1983 and 2004, 46 consecutive women of median age 41 years were treated by the same surgeon. Etiology of simple fistulas was iatrogenic (n=6), obstetric (n=4) and septic (n=3). Complex fistulas were due to inflammatory bowel diseases (IBD) (n=18, 11 pouchvaginal) or were iatrogenic (n=9), actinic (n=5) or septic (n=1). Surgical techniques included endorectal or vaginal advancement flaps, fistulectomy and sphincteroplasty, vaginal/rectal closure and epiploplasty, restorative proctectomy and restorative proctocolectomy. In 20 patients, a diverting stoma was performed as a single procedure or concomitant to the curative attempt. RESULTS: Overall, 33 of the 39 fistulas (85%) treated for cure healed, including all simple fistulas and 20 complex fistulas (8 iatrogenic, 3 actinic, 2 ulcerative colitis without restorative proctocolectomy; 5 pouch vaginal; 1 septic; 1 Crohn's disease) (p=0.009). The first operation for the fistula was curative in 20 of 39 fistulas, including 10 of 13 simple and 10 of 26 complex fistulas (p=0.023). There was no significant age difference between cured and not-cured patients. CONCLUSIONS: Simple versus complex fistulas is the most determinant factor for healing. In IBD fistulas, ulcerative colitis shows better prognosis than Crohn's disease. For complex fistulas, a temporary diverting stoma seems necessary.


Assuntos
Fístula Retovaginal/cirurgia , Adolescente , Adulto , Idoso , Feminino , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Fístula Retovaginal/etiologia , Estudos Retrospectivos , Resultado do Tratamento , Procedimentos Cirúrgicos Urológicos/métodos
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