Failed endotracheal intubation and adverse outcomes among extremely low birth weight infants.

OBJECTIVE: To quantify the importance of successful endotracheal intubation on the first attempt among extremely low birth weight (ELBW) infants who require resuscitation after delivery. STUDY DESIGN: A retrospective chart review was conducted for all ELBW infants ⩽1000 g born between January 2007 and May 2014 at a level IV neonatal intensive care unit. Infants were included if intubation was attempted during the first 5 min of life or if intubation was attempted during the first 10 min of life with heart rate <100. The primary outcome was death or neurodevelopmental impairment. The association between successful intubation on the first attempt and the primary outcome was assessed using multivariable logistic regression with adjustment for birth weight, gestational age, gender and antenatal steroids. RESULTS: The study sample included 88 ELBW infants. Forty percent were intubated on the first attempt and 60% required multiple intubation attempts. Death or neurodevelopmental impairment occurred in 29% of infants intubated on the first attempt, compared with 53% of infants that required multiple attempts, adjusted odds ratio 0.4 (95% confidence interval 0.1 to 1.0), P<0.05. CONCLUSION: Successful intubation on the first attempt is associated with improved neurodevelopmental outcomes among ELBW infants. This study confirms the importance of rapid establishment of a stable airway in ELBW infants requiring resuscitation after birth and has implications for personnel selection and role assignment in the delivery room.

Pulmonary hypertensive crisis following ethanol sclerotherapy for a complex vascular malformation.

Anhydrous ethanol is a commonly used sclerotic agent for treating vascular malformations. We describe the case of a full-term 15-day-old female with a complex venolymphatic malformation involving the face and orbit. During treatment of the lesion with ethanol sclerotherapy, she suffered acute pulmonary hypertensive crisis. We discuss the pathophysiology of pulmonary hypertension related to ethanol sclerotherapy, and propose that hemolysis plays a significant role. Recommendations for evaluation, monitoring and management of this complication are also discussed.

Impact of electronic medical record integration of a handoff tool on sign-out in a newborn intensive care unit.

OBJECTIVE: To evaluate the impact of integrating a handoff tool into the electronic medical record (EMR) on sign-out accuracy, satisfaction and workflow in a neonatal intensive care unit (NICU). STUDY DESIGN: Prospective surveys of neonatal care providers in an academic children's hospital 1 month before and 6 months following EMR integration of a standalone Microsoft Access neonatal handoff tool. RESULT: Providers perceived sign-out information to be somewhat or very accurate at a rate of 78% with the standalone handoff tool and 91% with the EMR-integrated tool (P < 0.01). Before integration of neonatal sign-out into the EMR, 35% of providers were satisfied with the process of updating sign-out information and 71% were satisfied with the printed sign-out document; following EMR integration, 92% of providers were satisfied with the process of updating sign-out information (P < 0.01) and 98% were satisfied with the printed sign-out document (P<0.01). Neonatal care providers reported spending a median of 11 to 15 min/day updating the standalone sign-out and 16 to 20 min/day updating the EMR-integrated sign-out (P = 0.026). The median percentage of total sign-out preparation time dedicated to transcribing information from the EMR was 25 to 49% before and <25% after EMR integration of the handoff tool (P < 0.01). CONCLUSION: Integration of a NICU-specific handoff tool into an EMR resulted in improvements in perceived sign-out accuracy, provider satisfaction and at least one aspect of workflow.

Identification of genes that confer tumor cell resistance to the aurora B kinase inhibitor, AZD1152.

AZD1152 is a highly selective Aurora B kinase inhibitor currently undergoing Phase I and II clinical evaluation in patients with acute myelogenous leukemia and advanced solid malignancies. We have established two AZD1152-resistant cell lines from SW620 colon and MiaPaCa pancreatic carcinoma lines, which are >100-fold resistant to the active metabolite of AZD1152, AZD1152 HQPA and interestingly, cross-resistant to the pan-Aurora kinase inhibitor, VX-680/MK0457. Using whole-genome microarray analysis and comparative genomic hybridization, we were able to identify MDR1 and BCRP as the causative genes that underlie AZD1152 HQPA-resistance in these models. Furthermore, the upregulation of either of these genes is sufficient to render in vivo tumor growth insensitive to AZD1152. Finally, the upregulation of MDR1 or BCRP is predictive of tumor cell sensitivity to this agent, both in vitro and in vivo. The data provide a genetic basis for resistance to Aurora kinase inhibitors, which could be utilized to predict clinical response to therapy.

Pathogenesis of virus-induced immune-mediated demyelination.

Theiler's murine encephalomyelitis virus-induced demyelinating disease has been extensively studied as an attractive infectious model for human multiple sclerosis. Virus-specific inflammatory Th1 cell responses followed by autoimmune responses to myelin antigens play a crucial role in the pathogenic processes leading to demyelination. Antibody and cytotoxic T cells (CTL) responses to virus appears to be primarily protective from demyelinating disease. Although the role of Th1 and CTL responses in the induction of demyelinating disease is controversial, assessment of cytokines produced locally in the central nervous system (CNS) during the course of disease and the effects of altered inflammatory cytokine levels strongly support the importance of Th1 responses in this virus-induced demyelinating disease. Induction of various chemokines and cytokines in different glial and antigen presenting cells upon viral infection appears to be an important initiation mechanism for inflammatory Th1 responses in the CNS. Coupled with the initial inflammatory responses, viral persistence in the CNS may be a critical factor for sustaining inflammatory responses and consequent immune-mediated demyelinating disease.

Enhanced susceptibility to Theiler's virus-induced demyelinating disease in perforin-deficient mice.

Theiler's virus induces immune-mediated demyelinating disease similar to human MS in susceptible mice. Though the MHC class II-restricted T cell response is critical, susceptibility/resistance is also associated with a MHC class I haplotype. Here we report that perforin-deficient C57BL/6 mice (pKO) are susceptible to demyelination and develop clinical disease. The levels of primary demyelination, proliferation, Th1 responses, and viral load were also markedly enhanced. In addition, immunization of pKO mice with UV-inactivated virus further enhanced clinical incidence and accelerated the disease course. Thus, perforin is most likely involved in viral clearance, hence protection from the disease.

Induction of selected chemokines in glial cells infected with Theiler's virus.

To elucidate the early events in Theiler's virus-induced demyelination, a model for human multiple sclerosis (MS), chemokine gene activation in the central nervous system (CNS) resident cells upon viral infection was investigated. Viral infection selectively upregulated RANTES and IP-10 gene expression in primary astrocyte cultures and broader chemokine genes in oligodendrocyte and microglia cultures. Both RANTES and IP-10 were stimulated by proinflammatory cytokine interferon-gamma (IFNgamma), but only RANTES by tumor necrosis factor alpha (TNFalpha), suggesting that virus infection induces chemokines overlapping with those inducible by proinflammatory cytokines. These results suggest that glial cells, astrocytes in particular, may be critical for early recruitment of inflammatory cells in the initiation of virus-induced, immune-mediated demyelination.

Pathogenic immunity in Theiler's virus-induced demyelinating disease: a viral model for multiple sclerosis.

Multiple sclerosis involves inflammatory immune responses in the central nervous system (CNS) and is considered as an autoimmune disease potentially associated with viral infection. The majority of experimental models rely heavily on the autoimmune components since similar diseases can be induced following immunization with various myelin antigens. A very attractive alternative model is the Theiler's murine encephalomyelitis virus-induced demyelinating disease. This disease is primarily a CD4+ T cell-mediated, inflammatory demyelinating disease induced following viral infection. Virus-specific inflammatory Th1 cell responses, rather than cytotoxic T lymphocyte response, play a critical role in the pathogenic immune responses. The major pathogenic epitopes have been identified and these are correlated with a Th1 type response to the epitopes following viral infection. In addition, the initial virus-specific immune response is followed by the autoimmune responses to myelin antigens. Assessment of cytokines produced locally in the CNS during the course of disease suggests involvement of inflammatory cytokines in the disease. Furthermore, the manipulation of inflammatory cytokine levels by administration of either recombinant cytokines or antibodies to the cytokines strongly influences the induction and/or progression of disease, supporting the importance of these inflammatory cytokines in this virus-induced demyelinating disease.

Potential role of CD4+ T cell-mediated apoptosis of activated astrocytes in Theiler's virus-induced demyelination.

Intracerebral inoculation of Theiler's murine encephalomyelitis virus (TMEV) into susceptible mouse strains results in a chronic, immune-mediated demyelinating disease similar to human multiple sclerosis. Here, we examined the role of astrocytes as an APC population in TMEV-induced demyelination and assessed the potential consequences of T cell activation following Ag presentation. IFN-gamma-pretreated astrocytes were able to process and present all the predominant T cell epitopes of TMEV to virus-specific T cell hybridomas, clones, as well as bulk T cells. Despite low levels of proliferation of T cells due to prostaglandins produced by astrocytes, such Ag presentation by activated astrocytes induced the production of IFN-gamma, a representative proinflammatory cytokine, in TMEV-specific Th cell clones derived from the CNS of virus-infected mice. Furthermore, these Th cell clones mediate lysis of the astrocytes in vitro in a Fas-dependent mechanism. TUNEL staining of CNS tissue demonstrates the presence of apoptotic GFAP+ cells in the white matter of TMEV-infected mice. These results strongly suggest that astrocytes could play an important role in the pathogenesis of TMEV-induced demyelination by activating T cells, subsequently leading to T cell-mediated apoptosis of astrocytes and thereby compromising the blood-brain barrier.

Role of individual T-cell epitopes of Theiler's virus in the pathogenesis of demyelination correlates with the ability to induce a Th1 response.

Intracerebral inoculation of susceptible strains of mice with Theiler's murine encephalomyelitis virus (TMEV) results in immune-mediated demyelination. Three major T-cell epitopes have previously been identified within the VP1 (VP1233-250), VP2 (VP274-86), and VP3 (VP324-37) capsid proteins in virus-infected SJL/J mice. These epitopes appear to account for the majority ( approximately 90%) of major histocompatibility complex class II-restricted T-cell responses to TMEV. Interestingly, the effect of immunization with synthetic peptides bearing the predominant T-cell epitopes on the course of TMEV-induced demyelination indicates that T cells reactive to the VP1 and VP2 epitopes, but not VP3, accelerate the pathogenesis of demyelination. The predominant pathogenic role of the T cells is verified by similar immunization with the fusion proteins containing the entire individual capsid proteins. The order of appearance and level of T cells specific for the individual epitopes during the course of demyelination are similar to each other. However, cytokine profiles of T cells from virus-infected mice indicate that T cells specific for the VP1 (and perhaps the VP2) epitope are Th1, whereas T cells reactive to VP3 are primarily Th2. These results suggest that Th1-type cells specific for VP1 and VP2 are involved in the pathogenesis of viral demyelination induced by TMEV. Thus, a predominance of Th1-inducing viral epitopes is likely critical for the pathogenesis of demyelination.

Treatment with lipopolysaccharide enhances the pathogenicity of a low-pathogenic variant of Theiler's murine encephalomyelitis virus.

Intracerebral infection of susceptible mouse strains with Theiler's murine encephalomyelitis virus (TMEV) results in an immune-mediated demyelinating disease (TMEV-IDD) similar to human multiple sclerosis (MS). Although the etiology of MS remains unknown, a role of an infectious agent has been implicated in its onset. Previously we have shown the ability of bacterial lipopolysaccharide (LPS) to alter susceptibility to TMEV-IDD in genetically resistant C57BL/6 mice. In this study, the potential of LPS to alter pathogenicity of a low/non-pathogenic variant of TMEV was investigated. After intraperitoneal treatment of genetically susceptible SJL/J mice with LPS before and during viral infection, 80-100% of the mice developed clinical symptoms, while without LPS treatment none of the mice were affected. However, clinical severity in these LPS-treated mice was much milder than the level induced by the wild type pathogenic virus. Increased susceptibility to the disease after LPS treatment did not correlate with splenic T cell proliferative responses against viral antigens. However, by reverse transcriptase polymerase chain reaction (RT-PCR) analyses, an early increase in the production of Th1-type proinflammatory cytokine messages (e.g., interferon-gamma [IFN-gamma] and enhancement of viral persistence was observed in the CNS of LPS-treated, virus-infected animals as compared to mice infected with the variant virus alone. These results indicate that environmental factors such as a bacterial infection (e.g., LPS) promoting proinflammatory cytokine production can significantly enhance the pathogenicity of demyelination induced by a normally non-pathogenic virus.

Cisplatin and carboplatin-mediated activation of murine peritoneal macrophages in vitro: production of interleukin-1 alpha and tumor necrosis factor-alpha.

Analysis of tissue culture supernatants collected from cisplatin (10 micrograms/ml) and carboplatin (50 micrograms/ml)-treated macrophages show enhanced activity of interleukin-1 alpha and tumor necrosis factor-alpha. Cytotoxicity of these supernatants was demonstrated using mouse sarcoma-180 cells. These results demonstrate the ability of cisplatin and carboplatin to enhance the immune system suggestive of yet another mechanism of their action in the regression of tumors.

Cisplatin and carboplatin mediated release of cytolytic factors in murine peritoneal macrophages in vitro.

The anticancer drugs cisplatin and carboplatin have been shown to activate murine peritoneal macrophages in vivo and in vitro. These activated macrophages have enhanced tumoricidal activity mediated by extension and contact formation with the tumor cells leading to an increase and transfer of lysosomes with eventual lysis of the tumor cells. Cisplatin (10 micrograms/ml) or carboplatin (50 micrograms/ml) for 2 and 24 h treatment of macrophages in vitro, in addition, show a significant increase in the release of various cytolytic factors, like hydrogen peroxide, superoxide anion, interleukin-1 alpha, lysozyme and beta-N-hexoseaminidase, that are also responsible for the destruction of tumor cells.

Murine macrophage activation after cisplatin or carboplatin treatment.

Murine peritoneal macrophages when treated in vitro with cisplatin (9 micrograms/ml) or carboplatin (50 micrograms/ml) for 2 h are stimulated to form cytoplasmic extensions seeking out tumor cells and establishing cytoplasmic connections; however, no contact is observed with normal cells (fibroblasts and hepatocytes). In addition, cisplatin and carboplatin treatment leads to an increase in the number of lysosomes and their transfer to the tumor cells resulting in lysis (as studied by confocal microscopy). Although calcium seems to be involved in the signalling of macrophage activation, cytosolic calcium does not seem to influence this activation.