Experience of Remifentanil in Extremely Low-birth-weight Babies Undergoing Laparotomy

Premature babies experience pain and require adequate analgesia for any painful procedure. Fentanyl and morphine resulted in safe and effective anesthesia in the past; however, their pharmacokinetics may be impaired in preterm babies with multiorgan failure. Remifentanil, despite the absence of available pharmacokinetic data in preterm infants and few reports in newborns, demonstrated its advantages in children undergoing either major surgery or minor painful procedures and has been shown to be useful even in neonates, because its elimination is independent of organ function. We report two cases of babies born at 26 weeks’ and 27 weeks’ gestation, weighing 580g and 400g, respectively, undergoing laparotomy for necrotizing enterocolitis. Both received midazolam bolus and remifentanil infusion at high doses. This technique seems to be an advantageous alternative even in extremely low-birth-weight prematures. Furthermore, it becomes a technique of choice in these babies because the available ventilators are often not equipped with halogenated vaporizers. Particularly in intensive care, where there are no scavenger systems, it could allow to operate without moving out the preterm babies and avoiding stress and hypothermia

Essential and unique roles of PIP5K-γ and -α in Fcγ receptor-mediated phagocytosis

The actin cytoskeleton is dynamically remodeled during Fcγ receptor (FcγR)-mediated phagocytosis in a phosphatidylinositol (4,5)-bisphosphate (PIP2)-dependent manner. We investigated the role of type I phosphatidylinositol 4-phosphate 5-kinase (PIP5K) γ and α isoforms, which synthesize PIP2, during phagocytosis. PIP5K-γ−/− bone marrow–derived macrophages (BMM) have a highly polymerized actin cytoskeleton and are defective in attachment to IgG-opsonized particles and FcγR clustering. Delivery of exogenous PIP2 rescued these defects. PIP5K-γ knockout BMM also have more RhoA and less Rac1 activation, and pharmacological manipulations establish that they contribute to the abnormal phenotype. Likewise, depletion of PIP5K-γ by RNA interference inhibits particle attachment. In contrast, PIP5K-α knockout or silencing has no effect on attachment but inhibits ingestion by decreasing Wiskott-Aldrich syndrome protein activation, and hence actin polymerization, in the nascent phagocytic cup. In addition, PIP5K-γ but not PIP5K-α is transiently activated by spleen tyrosine kinase–mediated phosphorylation. We propose that PIP5K-γ acts upstream of Rac/Rho and that the differential regulation of PIP5K-γ and -α allows them to work in tandem to modulate the actin cytoskeleton during the attachment and ingestion phases of phagocytosis

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Apporto della ecoendoscopia alla diagnosi ed alla stadiazione delle affezioni dell'esofago e dello stomaco: ricerca sperimentale

Dottorato di ricerca in chirurgia gastroenterologica. 6. ciclo. A.a. 1991-94Consiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal

The proto-oncogene Fgr regulates cell migration and this requires its plasma membrane localization

Fgr participates in integrin signaling in myeloid leukocytes. To examine the role of its specific domains in regulating cell migration, we expressed various Fgr molecules in COS-7 cells. Full-length, membrane-bound Fgr, but not an N-terminal truncation mutant that distributed to an intracellular compartment, increased cell migration on fibronectin and enhanced phosphorylation of the p85 subunit of phosphatidylinositol 3-kinase (PI3K), cortactin and focal adhesion kinase (FAK) at Y397 and Y576. Fgr increased Rac GTP loading, and phosphorylation of the Rac GEF Vav2, and bound to a protein complex formed by the Rho inhibitor p190RhoGAP and FAK, increasing p190RhoGAP phosphorylation, in a manner absolutely dependent on membrane localization. A kinase-defective truncation mutant of Fgr increased cell migration, albeit to a much lower extent than full-length Fgr, and was found to associate with the plasma membrane, to activate Rac and to form complexes with p190RhoGAP/FAK. Formation of complexes between p190RhoGAP, Fgr, and the FAK-related protein Pyk2 were also detected in murine macrophages. These findings suggest that the proto-oncogene Fgr regulates cell migration impinging on a signaling pathway implicating FAK/Pyk2 and leading to activation of Rac and the Rho inhibitor p190RhoGAP

Experience of Remifentanil in Extremely Low-birth-weight Babies Undergoing Laparotomy

Premature babies experience pain and require adequate analgesia for any painful procedure. Fentanyl and morphine resulted in safe and effective anesthesia in the past; however, their pharmacokinetics may be impaired in preterm babies with multiorgan failure. Remifentanil, despite the absence of available pharmacokinetic data in preterm infants and few reports in newborns, demonstrated its advantages in children undergoing either major surgery or minor painful procedures and has been shown to be useful even in neonates, because its elimination is independent of organ function. We report two cases of babies born at 26 weeks’ and 27 weeks’ gestation, weighing 580 g and 400 g, respectively, undergoing laparotomy for necrotizing enterocolitis. Both received midazolam bolus and remifentanil infusion at high doses. This technique seems to be an advantageous alternative even in extremely low-birth-weight prematures. Furthermore, it becomes a technique of choice in these babies because the available ventilators are often not equipped with halogenated vaporizers. Particularly in intensive care, where there are no scavenger systems, it could allow to operate without moving out the preterm babies and avoiding stress and hypothermia