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2.
Eur J Vasc Endovasc Surg ; 49(1): 60-5, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25510183

RESUMO

OBJECTIVE/BACKGROUND: Gut ischemia reperfusion (IR) is thought to trigger systemic inflammation, multiple organ failure, and death. The aim of this study was to investigate inflammatory responses in blood and in two target organs after gut IR. METHODS: This was a controlled animal study. Adult male Wistar rats were randomized into two groups of eight rats: control group and gut IR group (60 minutes of superior mesenteric artery occlusion followed by 60 minutes of reperfusion). Lactate and four cytokines (tumor necrosis factor-a, interleukin [IL]-1b, IL-6, and IL-10) were measured in mesenteric and systemic blood. The relative gene expression of these cytokines was determined by real time polymerase chain reaction in the gut, liver, and lung. RESULTS: Gut IR significantly increased lactate levels in mesenteric (0.9 ± 0.4 vs. 3.7 ± 1.8 mmol/L; p < .001) and in systemic blood (1.3 ± 0.2 vs. 4.0 ± 0.3 mmol/L; p < .001). Gut IR also increased the levels of four cytokines in mesenteric and systemic blood. IL-6 and IL-10 were the main circulating cytokines; there were no significant differences between mesenteric and systemic cytokine levels. IL-10 was upregulated mainly in the lung,suggesting that this organ could play a major role during gut reperfusion. CONCLUSION: The predominance of IL-10 over other cytokines in plasma and the dissimilar organ responses,especially of the lung, might be a basis for the design of therapies, for example lung protective ventilation strategies, to limit the deleterious effects of the inflammatory cascade. A multi-organ protective approach might involve gut directed therapies, protective ventilation, hemodynamic optimization, and hydric balance.


Assuntos
Compartimentos de Líquidos Corporais/metabolismo , Citocinas/sangue , Gastroenterite/complicações , Gastroenterite/metabolismo , Oclusão Vascular Mesentérica , Mesentério/irrigação sanguínea , Traumatismo por Reperfusão/metabolismo , Animais , Citocinas/genética , Expressão Gênica , Mucosa Intestinal/metabolismo , Isquemia , Fígado/metabolismo , Pulmão/metabolismo , Masculino , Artéria Mesentérica Superior , Distribuição Aleatória , Ratos , Ratos Wistar , Reperfusão , Traumatismo por Reperfusão/complicações , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
3.
Orthop Traumatol Surg Res ; 100(3): 313-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24703792

RESUMO

INTRODUCTION: The goal of this retrospective study was to compare pain control following total knee arthroplasty (TKA) on a perioperative protocol of local anesthesia (LA) versus the more classical femoral nerve block (FNB) technique. HYPOTHESIS: Fitness for discharge would be achieved earlier using the LA protocol. MATERIALS: Ninety-eight consecutive TKA patients operated on by a single surgeon were included with no selection criteria. In the study group (49 patients), 200 mL ropivacaine 5% was injected into the surgical wound and an intra-articular catheter was fitted to provide continuous infusion of 20 mL/h ropivacaine for 24h. The control group (49 patients) received ropivacaine FNB. Discharge fitness (independent walking, knee flexion>90°, quadricipital control, pain on VAS≤3) and hospital stay were assessed. RESULTS: Discharge fitness was achieved significantly earlier in the study group (4.2±2.6 versus 6.7±3.2 days; P=0.0003), with significantly shorter mean hospital stay (6.1±3.4 versus 8.8±3.5 days; P=0.0002). The complications rate did not differ between study and control groups. DISCUSSION: Although retrospective, this study indicates that the LA protocol improves management of post-TKA pain and accelerates rehabilitation, thereby, reducing hospital stay. The acceleration effect may be due to the absence of quadriceps inhibition. LEVEL OF EVIDENCE: Level III - Case control study.


Assuntos
Amidas/administração & dosagem , Anestesia Local/métodos , Artroplastia do Joelho , Bloqueio Nervoso/métodos , Manejo da Dor/métodos , Dor Pós-Operatória/terapia , Alta do Paciente/tendências , Idoso , Anestésicos Locais/administração & dosagem , Feminino , Nervo Femoral , Humanos , Injeções Intra-Articulares , Articulação do Joelho , Tempo de Internação/tendências , Masculino , Estudos Retrospectivos , Ropivacaina , Resultado do Tratamento
4.
Eur J Vasc Endovasc Surg ; 43(3): 339-40, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22237513

RESUMO

INTRODUCTION: Systemic capillary lactate, an end product of cellular anaerobic metabolism, has not established credibility in monitoring limb reperfusion. We assessed, in mice, whether local capillary lactate, arising from the reperfused limb, might be a relevant biomarker of reperfusion. REPORT: Systemic and local capillary lactate were sampled in the non-ischaemic and in the ischaemic limb. Only local lactate concentrations significantly increased after 2 h of ischaemia and decreased after reperfusion. DISCUSSION: Local, but not systemic, capillary lactate appeared as a potential reperfusion biomarker in this experimental acute limb ischaemia model.


Assuntos
Capilares/metabolismo , Membro Posterior/irrigação sanguínea , Isquemia/sangue , Isquemia/terapia , Ácido Láctico/sangue , Músculo Esquelético/metabolismo , Animais , Biomarcadores/sangue , Camundongos , Reperfusão
5.
Klin Padiatr ; 223(1): 22-6, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20862631

RESUMO

BACKGROUND: As diagnostic methods for primary ciliary dyskinesia are not generally available, we tested whether clinical criteria allow to preselect patients with a high probability of this disease, who should be further investigated in a specialized centre. PATIENTS AND METHODS: In patients with chronic cough we compared parameters of the case history with the finding of a reduced ciliary beat frequency (CBF). Data sheets of 323 patients (133 females, 190 males) aged 1 week through 40 years (median age 4.5 years) were available for analysis. Of these patients 46 (14%) had a reduced CBF. RESULTS: In this group the following features were found significantly more frequently compared to patients with normal CBF: neonatal respiratory disorder (odds ratio (OR) 9.0; 95% confidence interval (95% CI) 3.2;25), situs inversus (OR 8.1; 95% CI 2.5;26), retention of airway secretions (OR 6.7; 95% CI 2.4;19), recurrent pneumonia (OR 4.1; 95% CI 1.8;9.5), bronchiectasis (OR 3.5; 95% CI 1.2;11), asthma with poor response to treatment (OR 2.4; 95% CI 1.1;5.3). At least one of these potential indicators was present in 91% of the patients with reduced CBF. CONCLUSIONS: In patients with chronic cough specific parameters of the case history indicate a high probability of a reduced ciliary beat frequency which is an indicator for primary ciliary dyskinesia. If none of these findings is present, a reduced CBF is highly unlikely.


Assuntos
Tosse/etiologia , Síndrome de Kartagener/diagnóstico , Programas de Rastreamento , Inquéritos e Questionários , Adolescente , Adulto , Criança , Pré-Escolar , Doença Crônica , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Probabilidade , Fatores de Risco , Adulto Jovem
6.
Br J Anaesth ; 105(3): 342-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20650918

RESUMO

BACKGROUND: The loss of cholinergic neurones in the basal forebrain has been shown to correlate to the extent of cognitive dysfunction during ageing in humans and to the hypnotic potency of propofol in animal models. We examined how the preoperative cognitive status, as assessed by mini-mental state examination (MMSE), may interact with propofol consumption during anaesthesia in the elderly. METHODS: In a prospective study, we recruited 41 patients (65-99 yr) undergoing surgery for hip fracture. Femoral nerve block was performed for analgesia. Target-controlled infusion of propofol (Schnider's model) was adjusted to the bispectral index within the range 40-60. Multiple linear regression analysis determined whether age, BMI, gender, duration of anaesthesia, and preoperative MMSE score affected the propofol consumption (general linear model, Systat 8.0). RESULTS: BMI and MMSE score significantly affected the mean value of propofol consumption. A low MMSE score (below 19) was associated with an observed decrease in propofol requirement in patients >65 yr of age. No significant effect of age, gender, and duration of anaesthesia on the propofol consumption was observed. CONCLUSIONS: Propofol requirement to maintain hypnosis during general anaesthesia appears to decrease with deterioration in the cognitive status in the elderly. We suggest that a cognitive dysfunction linked to a cerebral cholinergic dysfunction may influence the brain sensitivity for propofol in aged patients.


Assuntos
Anestésicos Intravenosos/administração & dosagem , Cognição , Propofol/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Esquema de Medicação , Eletroencefalografia/efeitos dos fármacos , Feminino , Fraturas do Quadril/cirurgia , Humanos , Infusões Intravenosas , Masculino , Monitorização Intraoperatória/métodos , Testes Neuropsicológicos , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos
7.
Ann Fr Anesth Reanim ; 29(7-8): 579-81, 2010.
Artigo em Francês | MEDLINE | ID: mdl-20609554

RESUMO

This case report is an example of a bedside pretransfusion compatibility testing issue. An 81-years-old woman was admitted in the operating room for aortic valve replacement under cardiopulmonary bypass. A conflict occurred during the bedside pretransfusion compatibility testing between the results of the patient and the packed red blood cells. Afterwards, the patient was diagnosed with cold agglutinins. It might have produced false positive results with the anti-A and anti-B reagents.


Assuntos
Aglutininas , Incompatibilidade de Grupos Sanguíneos/diagnóstico , Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar/métodos , Transfusão de Eritrócitos/métodos , Hipotermia Induzida/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Idoso de 80 Anos ou mais , Valva Aórtica/cirurgia , Incompatibilidade de Grupos Sanguíneos/imunologia , Reações Falso-Positivas , Feminino , Implante de Prótese de Valva Cardíaca , Humanos
8.
Ann Fr Anesth Reanim ; 29(4): e51-8, 2010 Apr.
Artigo em Francês | MEDLINE | ID: mdl-20356707

RESUMO

The management of the PE patient requires admission in order to perform a meticulous assessment of the mothers' and fetal state, distinguishing between the severe and the mild forms. In moderate forms, the pregnancy is allowed to reach the 37(th) week of gestation. In severe forms of PE, the pregnancy is only allowed to continue under stringent monitoring. Before the 34(th) week of amenorrhea is reached, corticosteroid therapy and transfer to an adapted maternity are recommended. The true benefit provided by antihypertensive therapy in the moderate forms of PE is very limited. The presently recommended antihypertensive agent is nicardipine, which can be used in association with magnesium sulphate provided there is appropriate monitoring.


Assuntos
Hospitalização , Pré-Eclâmpsia/terapia , Corticosteroides/uso terapêutico , Adulto , Anti-Inflamatórios/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Feminino , Monitorização Fetal , Humanos , Compostos de Magnésio/uso terapêutico , Monitorização Fisiológica , Nicardipino/uso terapêutico , Pré-Eclâmpsia/diagnóstico , Gravidez
10.
J Gynecol Obstet Biol Reprod (Paris) ; 37 Suppl 8: S269-75, 2008 Dec.
Artigo em Francês | MEDLINE | ID: mdl-19268203

RESUMO

The aim of the anaesthesia for instrumental delivery is to provide optimal operation conditions for the obstetrician, appropriate maternal comfort, altogether with safety for the mother and her foetus. The type and location for this intervention are chosen individually for each case according to the indication, the risk of caesarean section and the local specificities. The general safety recommendations for obstetric anaesthesia apply in every case. Since an epidural analgesia is often already working, this type of anaesthesia is the most frequently used for the extractions. A spinal anaesthesia is a logical choice where an epidural in sot yet working. The pudendal block is a second line choice and the general anaesthesia remains as the last alternative in acute emergencies, in cases of failed regional anaesthesia or when the mother refuses any other anaesthesia despite proper information or proves unable to cooperate.


Assuntos
Anestesia Obstétrica , Extração Obstétrica , Analgesia Epidural , Anestesia Geral , Anestesia Obstétrica/efeitos adversos , Anestesia Obstétrica/métodos , Raquianestesia , Cesárea , Extração Obstétrica/métodos , Feminino , Humanos , Gravidez , Fatores de Risco
11.
Ter Arkh ; 79(4): 38-42, 2007.
Artigo em Russo | MEDLINE | ID: mdl-17564016

RESUMO

AIM: To optimize the differential diagnosis of nonmassive pulmonary thromboembolism (PTE) in patients emergently admitted to a multidisciplinary hospital. MATERIALS AND METHODS: The study enrolled 36 patients with nonmassive PTE and 28 with community-acquired pneumonias (ACP). All the patients underwent a comprehensive study, including primarily a clinical study in order to search for the early clinical manifestations of PTE. Ventilation-perfusion lung scintigraphy (VPLS) was performed in 11 patients with nonmassive PTE, 28 with ACP, and 10 healthy volunteers. RESULTS: The initial diagnosis of ACP was established in 26 of the 36 emergently hospitalized patients. Most early clinical manifestations of PTE and A CP were similar; their distinguishing features suggested that there might be nonmassive PTE. It is suggested that VPLS should be used for differential diagnosis in the above cases, by additionally assessing alveolar-capillary permeability. Twenty-eight patients with ACP were found to have a pronounced and significant acceleration of alveolar-capillary permeability in the affected lung at minutes 10 [23.5 +/- 1.9% (versus 8.02 +/- 3.89% in 11 patients with nonmassive PTE; p = 0.01)] and 30 of the study [33.4 +/- 1.9% (versus 13.64 +/- 4.0% in nonmassive PTE; p = 0.004)] while in nonmassive PTE, alveolar-capillary permeability corresponded to the values typical of healthy individuals, without exceeding 12 and 22% at minutes 10 and 30 of the study, respectively. CONCLUSION: VPLS makes it possible to verify or exclude the thromboembolic nature of pulmonary perfusion disorders. If it is difficult to make a diagnosis in the presence of the clinical symptoms characteristic of both nonmassive PTE and ACE, VPLS with an additional assessment of alveolar-capillary permeability, ACP substantially increases the accuracy of differential diagnosis of nonmassive PTE and ACE.


Assuntos
Infecções Comunitárias Adquiridas/diagnóstico , Pulmão , Pneumonia/diagnóstico , Embolia Pulmonar/diagnóstico , Adulto , Ambulâncias , Infecções Comunitárias Adquiridas/diagnóstico por imagem , Diagnóstico Diferencial , Hospitalização , Humanos , Pulmão/irrigação sanguínea , Pulmão/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Pneumonia/diagnóstico por imagem , Embolia Pulmonar/diagnóstico por imagem , Índice de Gravidade de Doença , Tomografia Computadorizada de Emissão , Tomografia Computadorizada por Raios X
12.
Clin Cancer Res ; 7(8): 2387-95, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11489817

RESUMO

PURPOSE: Analysis of tumor-derived genetic lesions has provided insights into molecular pathogenesis of human gliomas. Because these changes represent only one of several mechanisms that alter gene expression during tumorigenesis, it is likely that further information will be obtained from a careful analysis of important regulatory proteins present in these tumors. EXPERIMENTAL DESIGN: We have quantified the levels of key cell cycle/signaling proteins in 94 prospectively collected, meticulously preserved, "snap frozen" glioma specimens and have compared these levels with histopathological data and patient outcome. RESULTS: The results of these experiments confirm that the levels of wild-type tumor suppressor proteins, such as p53, pRB, PTEN, p14(ARF), and p16(INK4), are lost or severely reduced in most gliomas, and that epidermal growth factor receptor, 2human telomerase reverse transcriptase, and cyclin-dependent kinase 4 are overexpressed frequently and with a few exceptions, almost exclusively, in glioblastomas. In addition, we report frequent underexpression of E2F-1 (in 55% of gliomas) and cyclin E overexpression (in 26% of gliomas), which have not yet been reported on the genomic level. Several of these markers significantly correlated with histopathological grade, and the levels of five proteins showed significant association with patient outcome. In particular, overexpression of epidermal growth factor receptor, human telomerase reverse transcriptase, cyclin-dependent kinase 4, and cyclin E was largely restricted to glioblastomas and was significantly associated with reduced patient survivals. CONCLUSIONS: We conclude that the quantitation of cell cycle/signaling proteins from meticulously preserved glioma specimens provides further insights into the molecular pathogenesis of human gliomas and yields valuable prognostic information.


Assuntos
Proteínas de Ciclo Celular/análise , Glioma/patologia , Proteínas Proto-Oncogênicas , Proteínas Supressoras de Tumor , Western Blotting , Proteínas de Ciclo Celular/biossíntese , Ciclina D1/análise , Ciclina E/análise , Quinase 4 Dependente de Ciclina , Inibidor p16 de Quinase Dependente de Ciclina/análise , Quinases Ciclina-Dependentes/análise , Proteínas de Ligação a DNA , Receptores ErbB/análise , Glioma/metabolismo , Humanos , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases/análise , Prognóstico , Proteínas/análise , Proteína do Retinoblastoma/análise , Telomerase/análise , Proteína Supressora de Tumor p14ARF , Proteína Supressora de Tumor p53/análise
13.
Proc Natl Acad Sci U S A ; 98(19): 10851-6, 2001 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-11526205

RESUMO

The most common primary tumors of the human brain are thought to be of glial cell origin. However, glial cell neoplasms cannot be fully classified by cellular morphology or with conventional markers for astrocytes, oligodendrocytes, or their progenitors. Recent insights into central nervous system tumorigenesis suggest that novel molecular markers might be found among factors that have roles in glial development. Oligodendrocyte lineage genes (Olig1/2) encode basic helix-loop-helix transcription factors. In the rodent central nervous system, they are expressed exclusively in oligodendrocytes and oligodendrocyte progenitors, and Olig1 can promote formation of an chondroitin sulfate proteoglycon-positive glial progenitor. Here we show that human OLIG genes are expressed strongly in oligodendroglioma, contrasting absent or low expression in astrocytoma. Our data provide evidence that neoplastic cells of oligodendroglioma resemble oligodendrocytes or their progenitor cells and may derive from cells of this lineage. They further suggest the diagnostic potential of OLIG markers to augment identification of oligodendroglial tumors.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Proteínas de Ligação a DNA , Sequências Hélice-Alça-Hélice , Proteínas do Tecido Nervoso/genética , Oligodendroglia/metabolismo , Oligodendroglioma/genética , Astrocitoma/genética , Astrocitoma/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Neoplasias Encefálicas/patologia , Linhagem da Célula , Expressão Gênica , Humanos , Fator de Transcrição 2 de Oligodendrócitos , Oligodendroglioma/patologia , RNA Mensageiro
14.
Physiother Res Int ; 6(1): 40-51, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11379255

RESUMO

BACKGROUND AND PURPOSE: Investigation of the clinical reasoning skills of experienced clinicians provides insight into decision-making in the practice of physiotherapy. The purpose of the present study was to analyse the clinical reasoning skills of an experienced physiotherapist during her assessment and treatment of clients with low back pain. METHOD: Deconstruction of the physiotherapist's reasoning process was accomplished through observation of encounters between her and each of six patient subjects. Reconstruction and analysis of the physiotherapist's decision-making process was performed through retrospective interviews and reflective analysis of her clinical reasoning during each encounter. RESULTS: A working model of the physiotherapist's clinical reasoning was created from an integration of theoretical elements in the literature and the data. Through analysis of this framework, two core dimensions of her clinical reasoning were revealed: the influence of clinical experience and the influence of advanced training in a specific philosophy of treating the spine. CONCLUSIONS: The construction of these themes has contributed to the growing understanding of clinical reasoning strategies and skills used in orthopaedic physical therapy practice. Detailed description of the physiotherapist's reasoning process provides more meaningful understanding of physiotherapy treatments. In this case the physiotherapist employed a pattern recognition strategy and forward reasoning process in making a diagnosis. Further research is necessary to expand knowledge on the development of clinical reasoning skills.


Assuntos
Tomada de Decisões , Dor Lombar/terapia , Modalidades de Fisioterapia , Adulto , Feminino , Humanos , Dor Lombar/diagnóstico , Masculino , Pessoa de Meia-Idade , Modelos Psicológicos
15.
Exp Neurol ; 168(2): 300-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11259118

RESUMO

The simple ganglioside GM3 inhibits proliferation and induces apoptosis in proliferating immature rodent CNS cells. To determine whether GM3 influenced the expansion of human neural tumors the effects of GM3 treatment on primary human brain tumors were assayed. Here we demonstrate that GM3 treatment dramatically reduces cell numbers in primary cultures of high-grade human glioblastoma multiforme (GBM) tumors and the rat 9L cell gliosarcoma cell line. By contrast, GM3 treatment had little effect on cell number in cultures of normal human brain. A single injection of GM3 3 days after intracranial implantation of 9L tumor cells in a murine xenograft model system resulted in a significant increase in the symptom-free survival period of host animals. The effects of GM3 were not restricted to GBMs and 9L cells. Cultures of high-grade ependymomas, mixed gliomas, astrocytomas, oligodendrogliomas, and gangliogliomas were all susceptible to GM3 treatment. These results suggest that GM3 may have considerable value as a selectively toxic chemotherapeutic agent for human high-grade gliomas.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Gangliosídeo G(M3)/uso terapêutico , Glioma/tratamento farmacológico , Animais , Neoplasias Encefálicas/patologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Pré-Escolar , Ensaios de Seleção de Medicamentos Antitumorais , Gangliosídeo G(M3)/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioma/patologia , Humanos , Masculino , Camundongos , Ratos , Transplante Heterólogo , Células Tumorais Cultivadas/efeitos dos fármacos , Células Tumorais Cultivadas/fisiologia
16.
Dev Biol ; 227(2): 450-64, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11071766

RESUMO

Presenilin is an essential gene for development that when disrupted leads to a neurogenic phenotype that closely resembles Notch loss of function in Drosophila. In humans, many naturally occurring mutations in Presenilin 1 or 2 cause early onset Alzheimer's disease. Both loss of expression and overexpression of Presenilin suggested a role for this protein in the localization of Armadillo/beta-catenin. In blastoderm stage Presenilin mutants, Arm is aberrantly distributed, often in Ubiquitin-immunoreactive cytoplasmic inclusions predominantly located basally in the cell. These inclusions were not observed in loss of function Notch mutants, suggesting that failure to process Notch is not the only consequence of the loss of Presenilin function. Human presenilin 1 expressed in Drosophila produces embryonic phenotypes resembling those associated with mutations in Armadillo and exhibited reduced Armadillo at the plasma membrane that is likely due to retention of Armadillo in a complex with Presenilin. The interaction between Armadillo/beta-catenin and Presenilin 1 requires a third protein which may be delta-catenin. Our results suggest that Presenilin may regulate the delivery of a multiprotein complex that regulates Armadillo trafficking between the adherens junction and the proteasome.


Assuntos
Proteínas do Citoesqueleto/metabolismo , Proteínas de Drosophila , Drosophila/genética , Drosophila/metabolismo , Proteínas de Insetos/metabolismo , Proteínas de Membrana/metabolismo , Transativadores , Animais , Animais Geneticamente Modificados , Proteínas do Domínio Armadillo , Cateninas , Moléculas de Adesão Celular , Proteínas do Citoesqueleto/genética , Drosophila/embriologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Genes de Insetos , Humanos , Técnicas In Vitro , Proteínas de Insetos/genética , Proteínas de Membrana/genética , Modelos Biológicos , Mutação , Fenótipo , Fosfoproteínas , Presenilina-1 , Receptores Notch , Fatores de Transcrição , beta Catenina , delta Catenina
17.
Genetics ; 156(2): 763-74, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11014822

RESUMO

Raf is an essential downstream effector of activated p21(Ras) (Ras) in transducing proliferation or differentiation signals. Following binding to Ras, Raf is translocated to the plasma membrane, where it is activated by a yet unidentified "Raf activator." In an attempt to identify the Raf activator or additional molecules involved in the Raf signaling pathway, we conducted a genetic screen to identify genomic regions that are required for the biological function of Drosophila Raf (Draf). We tested a collection of chromosomal deficiencies representing approximately 70% of the autosomal euchromatic genomic regions for their abilities to enhance the lethality associated with a hypomorphic viable allele of Draf, Draf(Su2). Of the 148 autosomal deficiencies tested, 23 behaved as dominant enhancers of Draf(Su2), causing lethality in Draf(Su2) hemizygous males. Four of these deficiencies identified genes known to be involved in the Drosophila Ras/Raf (Ras1/Draf) pathway: Ras1, rolled (rl, encoding a MAPK), 14-3-3epsilon, and bowel (bowl). Two additional deficiencies removed the Drosophila Tec and Src homologs, Tec29A and Src64B. We demonstrate that Src64B interacts genetically with Draf and that an activated form of Src64B, when overexpressed in early embryos, causes ectopic expression of the Torso (Tor) receptor tyrosine kinase-target gene tailless. In addition, we show that a mutation in Tec29A partially suppresses a gain-of-function mutation in tor. These results suggest that Tec29A and Src64B are involved in Tor signaling, raising the possibility that they function to activate Draf. Finally, we discovered a genetic interaction between Draf(Su2) and Df(3L)vin5 that revealed a novel role of Draf in limb development. We find that loss of Draf activity causes limb defects, including pattern duplications, consistent with a role for Draf in regulation of engrailed (en) expression in imaginal discs.


Assuntos
Mapeamento Cromossômico , Drosophila melanogaster/genética , Proteínas Proto-Oncogênicas c-raf/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo , Animais , Cruzamentos Genéticos , Drosophila melanogaster/fisiologia , Elementos Facilitadores Genéticos , Feminino , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Larva , Masculino , Mutagênese , Fenótipo , Transdução de Sinais , Transcrição Gênica
19.
Neurosurgery ; 46(2): 419-30, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10690732

RESUMO

OBJECTIVE: Retinoids are known to exhibit a broad spectrum of biological activities, and they participate in the onset of differentiation and the inhibition of growth in a wide variety of cancer cells. Some of these vitamin A derivatives are already in clinical use. However, data on retinoid actions in glial tumors are rather sparse. Therefore, we studied the effects of the natural retinoic acid (RA) forms all-trans-RA, 9-cis-RA, and 13-cis-RA on glioma cell lines and primary cultures from patients with glioblastomas multiforme. METHODS: Six human glioma cell lines, one rat glioma cell line, and 20 primary cultures established from biopsies from patients with glioblastomas multiforme were investigated. Tumor cell proliferation was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and cell-counting assays. Random migration out of tumor spheroids was quantified using a video-morphometry system. Invasion was investigated using a confrontational coculture test system. Retinoid receptor (RA receptor [RAR]alpha, -beta, and -gamma and retinoid X receptor [RXR]alpha, -beta, and -gamma) expression status was determined using reverse transcription-polymerase chain reaction studies. RESULTS: Treatment of five human glioma cell lines with the different retinoids at concentrations up to 10(-5) mol/L produced no reduction of proliferation, using various incubation times. For one human glioma cell line (U343MG-A) and one rat glioma cell line (C6), which were previously reported to be sensitive to retinoids, we could confirm strong inhibitory effects on proliferation and clear changes in morphological features after retinoid treatment. Application of the different retinoids to low-passage primary cultures of human glioblastomas resulted in marked inhibition of proliferation (30-95%) for all tested samples. Using three-dimensional spheroid cultures, we detected retinoid-induced decreases in cell migration (24-65%). Invasion was not affected by these vitamin A derivatives. In an analysis of the expression patterns for retinoid receptors (RARs and RXRs), all primary culture samples yielded positive results for RAR gamma and RXR alpha and negative results for RAR alpha, RAR beta, and RXR gamma, whereas the results of RXR beta expression were heterogeneous among different patients. The cell lines, irrespective of their RA sensitivities, did not exhibit any major differences in receptor expression. CONCLUSION: Retinoids strongly inhibit proliferation and migration in primary cultures of human glioblastomas multiforme. Our data support a clinical trial of retinoids for the treatment of human malignant gliomas. We observed that most established cell lines were not sensitive to RA. This difference between long-term cell lines and primary cultures cannot be explained by different retinoid receptor expression patterns.


Assuntos
Neoplasias Encefálicas/patologia , Divisão Celular/efeitos dos fármacos , Glioblastoma/patologia , Retinoides/farmacologia , Células Tumorais Cultivadas/efeitos dos fármacos , Adulto , Idoso , Animais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Ratos , Relação Estrutura-Atividade , Células Tumorais Cultivadas/patologia
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