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1.
Prog Urol ; 32(8-9): 558-566, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35589469

RESUMO

PURPOSE: Image-based morphometric scoring systems such as the RENAL and PADUA scores are useful to evaluate the complexity of partial nephrectomy for renal cell carcinoma (RCC). The main aim of this study was to develop a new imaging software to enable an automatic detection and a 3D visualization of RCC from CT angiography (CTA) and to address the feasibility to use it to evaluate the features of the RENAL and the PADUA scores. METHODS: A training dataset of 210 patients CTA-scans manually segmented was used to train a deep learning algorithm to develop the automatic detection and 3D-visualization of RCC. A trained operator blindly assessed the RENAL and PADUA scores on a testing dataset of 41 CTA from patients with RCC using a commercialized semi-automatic software (ground truth) and the new automatic software. Concordance between the two methods was evaluated. RESULTS: The median PADUA score was 9 (7-11) and the renal score was 8 (5.5-9). The automatic software enabled to automatically detect the tumoral kidney and provided a 3D-visualization in all cases, with a computational time less than 20 seconds. Concordances for staging the anatomical features of the RENAL scores were respectively: 87.8% for radius, 85.4% for exophytic rate, 82.9% for location to the polar lines and 92.7% for the antero-posterior location. For the PADUA scores, concordances were 90.2% for tumor size, 85.4% for exophytic rate, 87.8% for polar location and 100% for renal rim. CONCLUSION: By enabling an automatic 3D-visualization of tumoral kidney, this software could help to calculate morphometric scores, save time and improve reproducibility for clinicians.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/cirurgia , Estudos de Viabilidade , Humanos , Rim/diagnóstico por imagem , Rim/patologia , Rim/cirurgia , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Nefrectomia/métodos , Projetos Piloto , Reprodutibilidade dos Testes , Estudos Retrospectivos , Software
2.
Prog Urol ; 31(14): 937-942, 2021 Nov.
Artigo em Francês | MEDLINE | ID: mdl-34456138

RESUMO

INTRODUCTION: Sate of the art on the indications, methods of implementation and medico-economic considerations of reusable flexible ureteroscopes (URSr) vs single use (URSuu)? METHOD: Review of the literature (Pubmed) on reusable and single-use ureteroscopes, as well as on the expertise of our center. A PubMed search and narrative review of the data was performed in July 2021. Only articles in French or English were selected. RESULTS: The URSr and URSuu have similar technical characteristics and are suitable for the exploration of the upper urinary excretory tract: treatment of stones of the kidney <2cm or of the ureter. The URSr is the most common type of ureteroscope. URSuu are newer and associated with many advantages: no sterilization procedure, immediate availability of equipment in the operating room, reduced waste production at the institutional level. A hybrid use of URSr and URSuu currently seems to be the best compromise from a medico-economic point of view for high volume centers. In the case of a smaller activity or a secondary site, URSuu are more advantageous and the reduction in purchasing costs should accentuate this benefit. CONCLUSION: URSr and URSuu are technically similar and allow identical treatment of upper urinary tract pathologies. Their complementary use optimizes the care of urology patients. The barrier to the exclusive use of URSuu remains their cost.


Assuntos
Ureteroscopia , Urologia , Desenho de Equipamento , Humanos , Salas Cirúrgicas , Ureteroscópios
3.
Minerva Anestesiol ; 81(3): 283-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25220554

RESUMO

BACKGROUND: Meropenem is a relatively unstable compound when dissolved. Currently, all available data have been derived from tests on the original product from Astrazeneca, and it is unsure if these data can be extrapolated to the stability of other commercially available vials. The aim of this study was therefore to assess the stability of four different brands of meropenem to be used as a prolonged or continuous infusion. METHODS: Commercially available meropenem vials were reconstituted and mixed with 0.9% sodium chloride to produce solutions with concentrations of 10.20 and 40 mg/mL in polypropylene syringes, which were kept at 25 °C. Samples were taken immediately after preparation and up to 12 hours. Solutions retaining >90% of the initial concentration were considered stable. RESULTS: The stability was concentration-dependent. At 25 °C, all 10 and 20 mg/mL solutions were stable for 12 hours in 0.9% sodium chloride, while the 40 mg/mL solutions were stable for a maximum of 8 hours. Stability of the different vials of meropenem was comparable for the time period tested (related samples Friedman's two way of analysis of variance by ranks, P=0.282). CONCLUSION: All tested commercially available vials of meropenem in a concentration of 10 and 20 mg/mL were stable for 12 hours at 25 °C when diluted in 0.9% sodium chloride. The 40 mg/mL solutions were stable for a maximum of 8 hours. This report is the first to show equivalent stability between different commercially available vials of meropenem.


Assuntos
Antibacterianos/análise , Tienamicinas/análise , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Soluções Isotônicas , Meropeném , Cloreto de Sódio , Seringas
4.
Transfus Clin Biol ; 20(2): 182-92, 2013 May.
Artigo em Francês | MEDLINE | ID: mdl-23587615

RESUMO

This work aim to present the descriptive analysis of serious adverse reactions in donors (dSAR's), which were notified in 2010 and 2011 in the French national haemovigilance database "e-FIT" (Internet secured haemovigilance reporting system). Some data, which are necessary for this analysis, also come from the regional haemovigilance coordinators' reports (RHC). The other parts of haemovigilance in the context of donation, without donors adverse reactions, such as post-donation information (PDI), adverse events occurred in the blood collection steps of the transfusion chain and epidemiology are not subject to this work analysis. This work shows that the quality of the data gradually improved since the setting up of the notification system of dSAR's. These data are particularly rich in learning lessons, but are still improving. It allows us to confirm that donor's safety, blood components quality, while preserving the blood components self-sufficiency in France, remains a priority. For these reasons, it is important to continue this haemovigilance awareness and to implement necessary actions that would be required for the protection of the donor's health and comfort during donation.


Assuntos
Remoção de Componentes Sanguíneos/efeitos adversos , Doadores de Sangue , Segurança do Sangue , Punções/efeitos adversos , Adolescente , Adulto , Idoso , Bancos de Sangue , Doadores de Sangue/legislação & jurisprudência , Doadores de Sangue/estatística & dados numéricos , Feminino , Controle de Formulários e Registros , França/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Unidades Móveis de Saúde , Isquemia Miocárdica/epidemiologia , Isquemia Miocárdica/etiologia , Dor/epidemiologia , Dor/etiologia , Síncope Vasovagal/epidemiologia , Síncope Vasovagal/etiologia , Tromboflebite/epidemiologia , Tromboflebite/etiologia , Infecção dos Ferimentos/epidemiologia , Infecção dos Ferimentos/etiologia , Adulto Jovem
5.
Transfus Clin Biol ; 19(6): 338-44, 2012 Dec.
Artigo em Francês | MEDLINE | ID: mdl-23103422

RESUMO

CONTEXT: Among the adverse events in the blood transfusion process, transfusion to a "wrong" patient is potentially dangerous, as it can lead to an adverse reaction at least in case of ABO incompatible red cell concentrate. MATERIAL AND METHODS: The "Root Cause Analysis" working party of the National Hemovigilance Commission developed a tool to collect this type of adverse event, and tested it on a sample of 43 cases involving red cell concentrates notified between March, 2009 and February, 2010. RESULTS: One hundred and nine failures of a step in the transfusion process were observed, i.e. 2.5 failures per adverse event. Failures may occur early in the process. However, they are mainly found at the time of issuing of the blood component, and further, in the clinical ward. How the failure is eventually detected is not always described when the blood component has been fully transfused, in contrast with the cases where actual transfusion to the wrong patient has been prevented. Knowing the way of failure detection enables an objective approach of the efficacy of the numerous existing safety measures. In this sample, bedside controls (documents check as well as the use of anti-A and anti-B reagents with patient's blood and red cell concentrates) detected the failure in three cases out of 34, which were not detected before, showing an efficacy similar to the administrative control done at reception in the clinical ward. CONCLUSION: The document, set up to analyse step by step these cases of patient errors, will be used in the future to analyse all similar cases, not only with red cell concentrates, but also with platelet concentrates and fresh frozen plasma, ultimately in order to improve their prevention.


Assuntos
Segurança do Sangue , Transfusão de Eritrócitos , Erros Médicos/estatística & dados numéricos , Seleção de Pacientes , Humanos
6.
Osteoporos Int ; 23(5): 1645-50, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21681611

RESUMO

Osteocalcin is a hormone secreted by osteoblasts, which regulates energy metabolism by increasing ß-cell proliferation, insulin secretion, insulin sensitivity, and energy expenditure. This has been demonstrated in mice, but to date, the evidence implicating osteocalcin in the regulation of energy metabolism in humans are indirect. To address this question more directly, we asked whether a benign osteoblastic tumor, such as osteoma osteoid in young adults, may secrete osteocalcin. The study was designed to assess the effect of surgical resection of osteoid osteoma on osteocalcin and blood glucose levels in comparison with patients undergoing knee surgery and healthy volunteers. Blood collections were performed the day of surgery and the following morning after overnight fasting. Patients and controls were recruited in the orthopedic surgery department of New York Presbiterian Hospital, NY-USA and Hospices Civils de Lyon, France. Seven young males were included in the study: two had osteoid osteoma, two underwent knee surgery, and three were healthy volunteers. After resection of the osteoid osteomas, we observed a decrease of osteocalcin by 62% and 30% from the initial levels. Simultaneously, blood glucose increased respectively by 32% and 15%. Bone turnover markers were not affected. This case study shows for the first time that osteocalcin in humans affects blood glucose level. This study also suggests that ostoid osteoma may be considered, at least in part, as an osteocalcinoma.


Assuntos
Glicemia/metabolismo , Neoplasias Ósseas/sangue , Osteoma Osteoide/sangue , Adulto , Biomarcadores/sangue , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/cirurgia , Humanos , Resistência à Insulina/fisiologia , Masculino , Osteocalcina/sangue , Osteocalcina/metabolismo , Osteocalcina/fisiologia , Osteoma Osteoide/metabolismo , Osteoma Osteoide/cirurgia , Período Pós-Operatório , Adulto Jovem
7.
Br J Radiol ; 82(976): 303-12, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19124567

RESUMO

For 318 patients in 8 different Belgian hospitals, the entire skin-dose distribution was mapped using a grid of 70 thermoluminescence dosimeters per patient, allowing an accurate determination of the maximum skin dose (MSD). Dose-area product (DAP) values, exposure parameters and geometry, together with procedure, patient and cardiologist characteristics, were also registered. Procedures were divided into two groups: diagnostic procedures (coronary angiography) and therapeutic procedures (dilatation, stent, combined procedures (e.g. coronary angiography + dilatation + stent)). The mean value of the MSD was 0.310 Gy for diagnostic and 0.699 Gy for therapeutic procedures. The most critical projection for receiving the MSD is the LAO90 (left anterior oblique) geometry. In 3% of cases, the MSD exceeded the 2 Gy dose threshold for deterministic effects. Action levels in terms of DAP values as the basis for a strategy for follow-up of patients for deterministic radiation skin effects were derived from measured MSD and cumulative DAP values. Two DAP action levels are proposed. A first DAP action level of 125 Gy cm(2) corresponding to the dose threshold of 2 Gy would imply an optional radiopathological follow-up depending on the cardiologist's decision. A second DAP action level of 250 Gy cm(2) corresponding to the 3 Gy skin dose would imply a systematic follow-up. Dose reference levels - 71.3 Gy cm(2) for diagnostic and 106.0 Gy cm(2) for therapeutic procedures - were derived from the 75 percentile of the DAP distributions. As a conclusion, we propose that total DAP is registered in patient's record file, as it can serve to improve the follow-up of patients for radiation-induced skin injuries.


Assuntos
Cateterismo Cardíaco/métodos , Lesões por Radiação/prevenção & controle , Monitoramento de Radiação/métodos , Radiografia Intervencionista/efeitos adversos , Pele/efeitos da radiação , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos Clínicos , Angiografia Coronária/métodos , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Doses de Radiação , Padrões de Referência , Fatores de Risco
11.
Ann Chir ; 130(6-7): 417-20, 2005.
Artigo em Francês | MEDLINE | ID: mdl-15982630

RESUMO

We report a case of postoperative inferior mesenteric arteriovenous fistula. Arteriovenous fistula represents a rare disease. Symptoms are due to portal hypertension and distal ischemy. Treatment of these fistulas is embolization. Surgery is possible by ligature or excision of the fistula because vascularisation is obtained by Riolan arcade and hypogastric artery.


Assuntos
Fístula Arteriovenosa/etiologia , Fístula Arteriovenosa/terapia , Embolização Terapêutica , Artérias Mesentéricas/patologia , Veias Mesentéricas/patologia , Complicações Pós-Operatórias , Fístula Arteriovenosa/complicações , Humanos , Hipertensão Portal/etiologia
12.
Acta Gastroenterol Belg ; 67(2): 188-96, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15285577

RESUMO

The authors present the results of a single centre study of 587 liver transplants performed in 522 adults during the period 1984-2002. Results have improved significantly over time due to better pre-, peri- and post-transplant care. One, five, ten and fifteen year actuarial survivals for the whole patient group are 81.2; 69.8; 58.9 and 51.2%. The high incidence of de novo tumors (12.3%), of cardiovascular diseases (7.5%) and of end-stage renal function (3.6%) should be further incentives to tailor the immunosuppression to the individual patient and to direct the attention of the transplant physician to the long-term quality of life of the liver recipient.


Assuntos
Transplante de Fígado , Adulto , Humanos , Imunossupressores/uso terapêutico , Análise de Sobrevida , Resultado do Tratamento
13.
EMBO J ; 20(20): 5603-14, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11598004

RESUMO

Proteins of the Wiskott-Aldrich syndrome and Ena/VASP families both play essential functions in the regulation of actin dynamics at the cell leading edge. However, possibilities of functional interplay between members of these two families have not been addressed. Here we show that, in hemopoietic cells, recruitment of the C-terminal VCA (Verprolin homology, Cofilin homology, Acidic) domain of WASp at the plasma membrane by a ligand technique using rapamycin as an intermediate is not sufficient to elicit efficient Arp2/3 complex-mediated actin polymerization. Other domains of WASp, in particular the proline-rich domain, are required for the formation of actin-rich structures. An in vitro analysis demonstrates that the proline-rich domain of WASp binds VASP with an affinity of approximately 10(6) M(-1). In addition, WASp and VASP both accumulate in actin-rich phagocytic cups. Finally, in a reconstituted motility medium, VASP enhances actin-based propulsion of WASp-coated beads in a fashion reminiscent of its effect on Listeria movement. We propose that VASP and WASp cooperation is essential in stimulating actin assembly and membrane protrusion at the leading edge.


Assuntos
Actinas/metabolismo , Moléculas de Adesão Celular/fisiologia , Proteínas do Citoesqueleto , Proteínas de Membrana/metabolismo , Fosfoproteínas/fisiologia , Proteínas/fisiologia , Proteína 2 Relacionada a Actina , Proteína 3 Relacionada a Actina , Actinas/química , Animais , Biopolímeros , Moléculas de Adesão Celular/química , Linhagem Celular , Movimento Celular , Cricetinae , Dimerização , Imunofluorescência , Rim , Leucemia Basofílica Aguda/patologia , Ligantes , Substâncias Macromoleculares , Mastócitos/metabolismo , Proteínas de Membrana/química , Mesocricetus , Proteínas dos Microfilamentos , Família Multigênica , Fagocitose , Fosfoproteínas/química , Prolina/química , Estrutura Terciária de Proteína , Proteínas/química , Ratos , Receptores de Interleucina-2/genética , Receptores de Interleucina-2/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sirolimo/metabolismo , Relação Estrutura-Atividade , Proteínas de Ligação a Tacrolimo/genética , Proteínas de Ligação a Tacrolimo/metabolismo , Transfecção , Células Tumorais Cultivadas , Proteína da Síndrome de Wiskott-Aldrich
14.
J Biol Chem ; 276(50): 46689-92, 2001 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11598103

RESUMO

In response to signaling, the Arp2/3 complex (actin-related proteins 2 and 3 complex) is activated by binding the C-terminal (WA) domain of proteins of the Wiskott-Aldrich Syndrome family to promote the formation of a branched actin filament array, responsible for cell protrusion. The Arp2/3 complex exists in different structural/functional states: the inactive Arp2/3, the activated WA.Arp2/3 complex, the ternary G-actin.WA.Arp2/3 complex, which branches the filaments. This work addresses the role of ATP binding in Arp2/3 function. Using photo-cross-linking, hydrodynamic, and fluorescence techniques, we show that in the inactive Arp2/3 complex only one rapidly exchangeable ATP is tightly bound to Arp3 with an affinity of 10(8) m(-1). Upon activation of the Arp2/3 complex by WA, ATP binds to Arp2 with high affinity (10(7) m(-1)), implying that a large structural change of Arp2 is linked to Arp2/3 activation. ATP is rapidly exchangeable on Arp2 and Arp3 in WA.Arp2/3 and G-actin.WA.Arp2/3 complexes. ATP is not hydrolyzed in inactive Arp2/3, in WA.Arp2/3, nor in G-actin.WA.Arp2/3. Arp2 has a greater specificity than Arp3 for ATP versus ATP analogs. Using functional assays of actin polymerization in branched filaments, we show that binding of ATP to Arp2 is required for filament branching.


Assuntos
Actinas/metabolismo , Proteínas do Citoesqueleto , Proteínas/metabolismo , Proteína 2 Relacionada a Actina , Proteína 3 Relacionada a Actina , Trifosfato de Adenosina/metabolismo , Animais , Sítios de Ligação , Bovinos , Relação Dose-Resposta a Droga , Hidrólise , Cinética , Modelos Biológicos , Modelos Químicos , Ligação Proteica , Proteínas/química , Coelhos , Espectrometria de Fluorescência , Fatores de Tempo , Proteína da Síndrome de Wiskott-Aldrich
15.
Science ; 292(5521): 1502-6, 2001 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-11379633

RESUMO

Spatially controlled polymerization of actin is at the origin of cell motility and is responsible for the formation of cellular protrusions like lamellipodia. The pathogens Listeria monocytogenes and Shigella flexneri, which undergo actin-based propulsion, are acknowledged models of the leading edge of lamellipodia. Actin-based motility of the bacteria or of functionalized microspheres can be reconstituted in vitro from only five pure proteins. Movement results from the regulated site-directed treadmilling of actin filaments, consistent with observations of actin dynamics in living motile cells and with the biochemical properties of the components of the synthetic motility medium.


Assuntos
Actinas/fisiologia , Movimento Celular , Proteínas do Citoesqueleto , Listeria monocytogenes/fisiologia , Fatores de Despolimerização de Actina , Proteína 2 Relacionada a Actina , Proteína 3 Relacionada a Actina , Actinas/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Biopolímeros , Destrina , Proteínas dos Microfilamentos/metabolismo , Modelos Biológicos , Movimento , Proteínas/metabolismo , Pseudópodes/fisiologia , Transdução de Sinais , Proteína da Síndrome de Wiskott-Aldrich
16.
Biochemistry ; 39(40): 12295-302, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11015208

RESUMO

Stathmin is an important protein that interacts with tubulin and regulates microtubule dynamics in a phosphorylation-controlled fashion. Here we show that the dissociation of guanosine 5'-diphosphate (GDP) from beta-tubulin is slowed 20-fold in the (tubulin)(2)-stathmin ternary complex (T(2)S). The kinetics of GDP or guanosine 5'-triphosphate (GTP) dissociation from tubulin have been monitored by the change in tryptophan fluorescence of tubulin upon exchanging 2-amino-6-mercapto-9-beta-ribofuranosylpurine 5'-diphosphate (S6-GDP) for tubulin-bound guanine nucleotide. At molar ratios of stathmin to tubulin lower than 0.5, biphasic kinetics were observed, indicating that the dynamics of the complex is extremely slow, consistent with its high stability. The method was used to characterize the effects of phosphorylation of stathmin on its interaction with tubulin. The serine-to-glutamate substitution of all four phosphorylatable serines of stathmin (4E-stathmin) weakens the stability of the T(2)S complex by about 2 orders of magnitude. The phosphorylation of serines 16 and 63 in stathmin has a more severe effect and weakens the stability of T(2)S 10(4)-fold. The rate of GDP dissociation is lowered only 7-fold and 4-fold in the complexes of tubulin with 4E-stathmin and diphosphostathmin, respectively. Sedimentation velocity studies support the conclusions of nucleotide exchange data and show that the T(2)S complexes formed between tubulin and 4E-stathmin or diphosphostathmin are less compact than the highly stable T(2)S complex. The correlation between the effect of phosphorylation of stathmin on the stability of T(2)S complex measured in vitro and on the function of stathmin in vivo is discussed.


Assuntos
Fatores de Troca do Nucleotídeo Guanina/fisiologia , Guanosina Difosfato/metabolismo , Proteínas dos Microtúbulos , Fosfoproteínas/fisiologia , Tubulina (Proteína)/metabolismo , Animais , Bovinos , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Guanosina Trifosfato/metabolismo , Cinética , Substâncias Macromoleculares , Fosfoproteínas/metabolismo , Fosforilação , Espectrometria de Fluorescência , Estatmina , Triptofano , Ultracentrifugação
17.
J Biol Chem ; 275(29): 21946-52, 2000 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-10781580

RESUMO

Proteins of the Wiskott-Aldrich Syndrome protein (WASp) family connect signaling pathways to the actin polymerization-driven cell motility. The ubiquitous homolog of WASp, N-WASp, is a multidomain protein that interacts with the Arp2/3 complex and G-actin via its C-terminal WA domain to stimulate actin polymerization. The activity of N-WASp is enhanced by the binding of effectors like Cdc42-guanosine 5'-3-O-(thio)triphosphate, phosphatidylinositol bisphosphate, or the Shigella IcsA protein. Here we show that the SH3-SH2-SH3 adaptor Grb2 is another activator of N-WASp that stimulates actin polymerization by increasing the amount of N-WASp. Arp2/3 complex. The concentration dependence of N-WASp activity, sedimentation velocity and cross-linking experiments together suggest that N-WASp is subject to self-association, and Grb2 enhances N-WASp activity by binding preferentially to its active monomeric form. Use of peptide inhibitors, mutated Grb2, and isolated SH3 domains demonstrate that the effect of Grb2 is mediated by the interaction of its C-terminal SH3 domain with the proline-rich region of N-WASp. Cdc42 and Grb2 bind simultaneously to N-WASp and enhance actin polymerization synergistically. Grb2 shortens the delay preceding the onset of Escherichia coli (IcsA) actin-based reconstituted movement. These results suggest that Grb2 may activate Arp2/3 complex-mediated actin polymerization downstream from the receptor tyrosine kinase signaling pathway.


Assuntos
Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Proteínas do Citoesqueleto , Proteínas/metabolismo , Transdução de Sinais , Proteína 2 Relacionada a Actina , Proteína 3 Relacionada a Actina , Animais , Receptores ErbB/metabolismo , Proteína Adaptadora GRB2 , Humanos , Coelhos , Proteínas Recombinantes/metabolismo , Síndrome de Wiskott-Aldrich , Proteína da Síndrome de Wiskott-Aldrich
18.
Anesth Analg ; 89(5): 1137-42, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10553824

RESUMO

UNLABELLED: Children with Alagille's syndrome are at increased perioperative risk during orthotopic liver transplantation due to the cardiopulmonary abnormalities and the hemodynamic changes associated with this procedure. We studied 16 children with Alagille's syndrome who underwent 21 orthotopic liver transplantations. Peripheral pulmonary stenosis was present in all subjects. Right ventricular pressures were increased in 15 cases. Caval clamping resulted in a mean decrease of 15 +/-9 mm Hg in systolic blood pressure, 5 +/- 3 mm Hg in mean pulmonary artery pressure, and 4 +/- 3 mm Hg in central venous pressure. Systolic blood pressure decreased by 16 +/- 13 mm Hg, whereas mean pulmonary artery pressure and central venous pressure increased by 3 +/- 4 mm Hg and 1 +/- 4 mm Hg, respectively, at portal vein unclamping. There was no correlation between severity of pulmonary artery stenosis and hemodynamic changes. Veno-venous bypass used in four cases resulted in smaller hemodynamic changes. Time to extubation and duration of intensive care unit stay were unrelated to severity of pulmonary artery stenosis. IMPLICATIONS: Some children with Alagille's syndrome require liver transplantation. In our study, associated pulmonary artery stenosis did not dramatically increase perioperative risk. Veno-venous bypass decreased intraoperative hemodynamic changes in these patients.


Assuntos
Síndrome de Alagille/cirurgia , Hemodinâmica , Transplante de Fígado , Síndrome de Alagille/complicações , Síndrome de Alagille/fisiopatologia , Pressão Sanguínea , Pressão Venosa Central , Criança , Pré-Escolar , Constrição Patológica , Feminino , Humanos , Lactente , Masculino , Artéria Pulmonar/patologia , Artéria Pulmonar/fisiopatologia , Estudos Retrospectivos
19.
Acta Gastroenterol Belg ; 62(3): 306-18, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10547897

RESUMO

OBJECTIVE: To evaluate the impact of standardized operative and peri-operative care on the outcome of liver transplantation in a single center series of 395 adult patients. METHOD AND MATERIAL: Between February 1984 and December 31, 1998, 451 orthotopic liver transplantations were performed in 395 adult patients (> or = 15 years) at the University Hospitals St-Luc in Brussels. Morbidity and mortality of the periods 1984-1990 (Gr I--174 pat.) and 1991-1998 were compared (Gr II--221 pat.). During the second period anti-infectious chemotherapy and perioperative care were standardized and surgical technique changed from classical orthotopic liver transplantation with recipients' vena cava resection (and use of veno-venous bypass) towards liver implantation with preservation of the vena cava (without use of bypass). Immunosuppression was cyclosporine based from 1984 up to 1996 and tacrolimus based during the years 1997 and 1998. Immunosuppression was alleviated during the second period due to change from quadruple to triple and even double therapy and due to the introduction of low steroid dosing and of steroid withdrawal, once stable graft function was obtained. Indications for liver grafting were chronic liver disease (284 pat--71.9%), hepatobiliary tumor (52 pat--13.2%), acute liver failure (40 pat--10.1%) and metabolic disease (19 pat--4.8%). Regrafting was necessary because of graft dysfunction (21 pat), technical failure (12 pat), immunological failure (18 pat) and recurrent viral allograft disease (5 pat); three of these patients were regrafted at another institution. Follow-up was complete for all patients with a minimum of 9 months. RESULTS: Actuarial 1, 5 and 10 years survival rates for the whole group were 77.9%, 65.7% and 58.3%. These survival rates were respectively 77.3%, 69.7%, 62.5% and 73.2%, 59.6% 51.4% for benign chronic liver disease and acute liver failure; those for malignant liver disease were 80.6%, 44.3% and 36.7%. Early (< 3 months) and late (> 3 months) posttransplant mortalities were. 14.4% (57 pat) and 21.2% (84 pat). Early mortality lowered from 20% in Gr I to 9.4% in Gr II (p < 0.02); this was due to a significant reduction during the second period of bacterial (99/174 pat.--56.9% vs 82/221 pat.--37.1%), fungal (14 pat.--8% vs 7 pat.--3.2%) and viral (87 pat.--50% vs 49 pat.--22.2%) infections (p < 0.05) as well as of perioperative bleeding (92 pat.--52.9% vs 39 pat.--17.6%--p < 0.001). Late mortality remained almost identical throughout the two periods as lethal outcome was mainly caused by recurrent allograft diseases, cardiovascular and tumor problems. Morbidity in these series was important considering that almost, half of the patients had a technical complication, mostly related to bleeding (131 pat--33.2%) and biliary problems (66 pat--16.7%). Retransplantation index was 1.1 (54 pat.--14%). Early retransplantation mortality was 24%; it lowered, although not yet significantly, during the second period (8/25 pat.--32% vs. 5/29 pat.--17.2%). CONCLUSION: Despite a marked improvement of results, liver transplantation remains a major medical and surgical undertaking. Standardization of operative and perioperative care, less haemorraghic surgery and less aggressive immunosuppression are the keys for further improvement.


Assuntos
Hepatopatias/cirurgia , Transplante de Fígado/estatística & dados numéricos , Adolescente , Adulto , Idoso , Bélgica , Controle de Custos , Humanos , Terapia de Imunossupressão , Transplante de Fígado/métodos , Transplante de Fígado/mortalidade , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Taxa de Sobrevida
20.
Nature ; 401(6753): 613-6, 1999 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-10524632

RESUMO

Actin polymerization is essential for cell locomotion and is thought to generate the force responsible for cellular protrusions. The Arp2/3 complex is required to stimulate actin assembly at the leading edge in response to signalling. The bacteria Listeria and Shigella bypass the signalling pathway and harness the Arp2/3 complex to induce actin assembly and to propel themselves in living cells. However, the Arp2/3 complex alone is insufficient to promote movement. Here we have used pure components of the actin cytoskeleton to reconstitute sustained movement in Listeria and Shigella in vitro. Actin-based propulsion is driven by the free energy released by ATP hydrolysis linked to actin polymerization, and does not require myosin. In addition to actin and activated Arp2/3 complex, actin depolymerizing factor (ADF, or cofilin) and capping protein are also required for motility as they maintain a high steady-state level of G-actin, which controls the rate of unidirectional growth of actin filaments at the surface of the bacterium. The movement is more effective when profilin, alpha-actinin and VASP (for Listeria) are also included. These results have implications for our understanding of the mechanism of actin-based motility in cells.


Assuntos
Actinas/fisiologia , Proteínas Contráteis , Proteínas do Citoesqueleto , Listeria monocytogenes/fisiologia , Shigella/fisiologia , Fatores de Despolimerização de Actina , Proteína 2 Relacionada a Actina , Proteína 3 Relacionada a Actina , Trifosfato de Adenosina/fisiologia , Animais , Proteínas de Bactérias , Bovinos , Moléculas de Adesão Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Escherichia coli/fisiologia , Humanos , Proteínas dos Microfilamentos/fisiologia , Movimento , Proteínas do Tecido Nervoso/fisiologia , Fosfoproteínas/fisiologia , Profilinas , Coelhos , Proteínas Recombinantes , Fatores de Transcrição/fisiologia , Proteína Neuronal da Síndrome de Wiskott-Aldrich
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