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1.
Acta Paediatr ; 91(7): 822-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12200910

RESUMO

UNLABELLED: The aim of this study was to investigate pain management in neonatal intensive care units (NICUs) in France and to identify factors associated with variability across units. A questionnaire sent to 143 heads of level II or III NICUs investigated the use of pain scores, pain management organization and pharmacological treatment in five clinical situations (endotracheal intubation, prolonged mechanical ventilation, acute stage of necrotizing enterocolitis, central venous catheter insertion and cephalhaematoma). The response rate was 81%. Among the 35 (30%) units that used no pain scores, 40% ascribed this to lack of knowledge. Factors associated with failure to use pain scores were level II status, no university affiliation, no surgical patients and neonatal patients only. Among the units that scored pain, 78% used valid scores for acute pain and 73% for prolonged pain. Written guidelines were available for acute pain in 65% of units and for prolonged pain in 36%. The rate of pharmacotherapy use varied widely across the five clinical situations studied (from 16 to 77%) and across units for a given clinical situation. Also extremely variable were the regimens used in each situation and the dosages of analgesics and sedatives. Only 11% of units adjusted dosages to gestational age. CONCLUSION: Pain assessment was performed in the most French NICUs, but a strong heterogeneity for pain treatment was observed. Reference to recently published pain management guidelines and new randomized trials could be useful to optimize pain treatment in NICUs.


Assuntos
Unidades de Terapia Intensiva Neonatal/normas , Manejo da Dor , Qualidade da Assistência à Saúde , Analgésicos/uso terapêutico , França , Pesquisas sobre Atenção à Saúde , Humanos , Recém-Nascido , Dor/tratamento farmacológico , Medição da Dor/métodos , Estudos Prospectivos , Estatísticas não Paramétricas , Inquéritos e Questionários
2.
Eur J Biochem ; 268(4): 1006-19, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11179967

RESUMO

The complete coding sequences of three rat alpha1,2fucosyltransferase genes were obtained. Sequence analysis revealed that these genes, called FTA, FTB and FTC, were homologous to human FUT1, FUT2 and Sec1, respectively. A distance analysis between all alpha1,2fucosyltransferase sequences available showed that the two domains of the catalytic region evolved differently with little divergence between the FUT2 and Sec1 N-terminal domains, quite distant from that of FUT1. At variance, FUT1 and FUT2 C-terminal domains were less distant while a high evolutionary rate was noted for Sec1 C-terminal domain. Whereas FTA and FTB encode typical glycosyltransferases, FTC lacks the homologous start codon and encodes a protein devoid of intracellular and transmembrane domains. It is located on rat chromosome 1q34. Transfection experiments revealed that unlike FTA and FTB, FTC does not generate enzyme activity. Analysis by flow cytometry showed that H type 2 epitopes were synthesized in Chinese hamster ovary cells transfected by both FTA and FTB cDNA, but only FTB transfectants possessed H type 3 determinants. In REG rat carcinoma cells, both FTA and FTB allowed synthesis of H type 2 and H type 3 at the cell surface. Western blots showed that, in both cell types, FTA was able to synthesize H type 2 epitopes on a larger set of glycoproteins than FTB. Analysis of the kinetic parameters obtained using small oligosaccharides revealed only a slight preference of FTA for type 2 over other types of acceptor substrates, whereas FTB was barely able to fucosylate this substrate.


Assuntos
Fucosiltransferases/genética , Sistema ABO de Grupos Sanguíneos/biossíntese , Sequência de Aminoácidos , Animais , Sequência de Bases , Células CHO , Células COS , Mapeamento Cromossômico , Cricetinae , Fucosiltransferases/metabolismo , Fucosiltransferases/fisiologia , Cinética , Dados de Sequência Molecular , Filogenia , Ratos , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas , Galactosídeo 2-alfa-L-Fucosiltransferase
3.
Int J Cancer ; 86(5): 713-7, 2000 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10797295

RESUMO

The presence of alpha1,2-fucosylated glycans at the surface of rat colon carcinoma cells has been associated with an increased tumorigenicity and resistance to natural killer/lymphokine activated killer (NK/LAK) cytotoxicity. We now report that transfection of rat alpha1,2-fucosyltransferases cDNA (FTA and FTB) into REG cells, which are spontaneously devoid of this enzymatic activity, allows expression of histo-blood group H antigen and increases their resistance to LAK, but not NK cell lysis. Conversely, transfection of PRO cells, which spontaneously express alpha1, 2-fucosyltransferase activity, with the FTA cDNA in the antisense orientation decreases expression of the H antigen together with their resistance to LAK cell lysis, but again, not to NK cell lysis. Furthermore, REG cells that are rejected by immunocompetent syngeneic rats are similarly rejected by rats depleted of NK cells by antibody 3.2.3, directed against the NKR-P1 molecule. Thus, the rejection of REG cells by immunocompetent rats and their earlier reported increased tumorigenicity after transfection with an alpha1, 2-fucosyltransferase cDNA cannot be ascribed to NK cell sensitivity or resistance, respectively. The increased resistance to LAK cell lysis, however, may be relevant to tumor progression.


Assuntos
Neoplasias do Colo/imunologia , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Naturais/imunologia , Linfocinas/imunologia , Animais , Citotoxicidade Imunológica , Fucosiltransferases/genética , Fucosiltransferases/metabolismo , Ratos , Transfecção , Células Tumorais Cultivadas
4.
Glycobiology ; 10(4): 375-82, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10764825

RESUMO

Accumulation of histo-blood group antigens such as Lewis b, Lewis Y and H in colon cancer is indicative of poor prognosis. It is accompanied by increase in alpha1,2fucosyl-transferase activity, a key enzyme for synthesis of these antigens. Using a model of colon carcinoma, we previously showed that alpha1,2fucosylation increases tumorigenicity. We now show that tumorigenicity inversely correlates with the cells' sensitivity to apoptosis. In addition, poorly tumorigenic REG cells independently transfected with three different alpha1,2fucosyltransferase cDNAs, the human FUT1, the rat FTA and FTB were more resistant than control cells to apoptosis induced in vitro by serum deprivation. Inversely, PRO cells, spontaneously tumorigenic in immunocompetent syngeneic animals and able to synthesize alpha1,2fucosylated glycans, became more sensitive to apoptosis after transfection with a fragment of the FTA cDNA in the antisense orientation. Expression of alpha1,2fucosyl-transferase in poorly tumorigenic REG cells dramatically enhanced their tumorigenicity in syngeneic rats. However, in immunodeficient animals, both control and alpha1,2fuco-syltransferase transfected REG cells were fully tumorigenic and metastatic, indicating that the presence of alpha1,2fucosylated antigens allowed REG tumor cells to escape immune control. Taken together, the results show that increased tumorigenicity mediated by alpha1,2fucosyl-ation is associated to increased resistance to apoptosis and to escape from immune control.


Assuntos
Apoptose , Neoplasias do Colo/patologia , Fucosiltransferases/metabolismo , Animais , Antígenos de Bactérias/análise , Neoplasias do Colo/enzimologia , Neoplasias do Colo/imunologia , DNA Complementar/genética , Fucose/metabolismo , Fucosiltransferases/genética , Humanos , Camundongos , Camundongos SCID , Ratos , Transfecção , Células Tumorais Cultivadas , Galactosídeo 2-alfa-L-Fucosiltransferase
5.
Int J Cancer ; 80(4): 606-11, 1999 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-9935164

RESUMO

Accumulation of histo-blood group antigens such as Lewis b, Lewis Y and H increases tumor cell motility and tumorigenesis. Alpha1,2-fucosylation is a key step in the synthesis of these antigens. Two alpha1,2-fucosyltransferases, expressed in colorectal carcinomas, have been characterized (FUT1 and FUT2 in humans, FTA and FTB in rats). To define the relative contribution of each of these enzymes in tumor cell behavior, we have used an anti-sense transfection approach in rat colon carcinoma PROb cells, which synthesize mRNA encoding for both enzymes. We have previously reported that anti-sense transfection of a cDNA fragment of the FTB enzyme decreased H antigenic cell-surface levels and concomitantly decreased tumorigenicity. H antigens, detected by antibodies specific for H type 1, 3 or 4, were detected only on a splice variant of CD44 containing the product of exon v6. We now report the anti-sense transfection of an FTA cDNA fragment into PROb cells, which resulted in decreased enzymatic activity on a type 2 precursor and decreased cell-surface H type 2 antigen exclusively. Compared to controls, FTA anti-sense-transfected cells were significantly more tumorigenic in syngeneic animals but not in immunodeficient SCID mice. The UEA-I lectin, specific for H type 2, revealed that these structures were present on the CD44v6 variant and on an uncharacterized 80-kDa glycoprotein. Our results indicate that FTA and FTB fucosylate distinct glycan chains in the same cell, leading to opposite effects, under control of the immune system.


Assuntos
Neoplasias do Colo/genética , DNA Antissenso/genética , DNA Complementar/genética , Fucosiltransferases/genética , Proteínas de Neoplasias/genética , Animais , Neoplasias do Colo/patologia , DNA Antissenso/metabolismo , Fucosiltransferases/metabolismo , Camundongos , Camundongos SCID , Proteínas de Neoplasias/metabolismo , Ratos , Transfecção , Células Tumorais Cultivadas , Galactosídeo 2-alfa-L-Fucosiltransferase
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