Maternal cardiac arrest in early pregnancy

A primigravid woman suffered a prolonged cardiac arrest at 18 weeks of gestation. Dilated ischemic cardiomyopathy was diagnosed. After recovery, the patient received an implantable cardioverter-defibrillator. At 38 weeks of gestation she had an elective caesarean delivery. Both mother and child had a favourable outcome. The effect of pregnancy on underlying cardiac disease and the management of maternal cardiac arrest with a pre-viable fetus are discussed. The importance of a multidisciplinary approach is emphasized. Continued neurodevelopmental assessment of the newborn is necessary to detect the long-term effects of fetal hypoxia in early pregnancy.     

Addition of interferon-alpha to a standard maturation cocktail induces CD38 up-regulation and increases dendritic cell function

Monocyte-derived dendritic cells (DCs) are used as adjuvant cells in cancer immunotherapy and have shown promising results. In order to obtain full functional capacity, these DCs need to be maturated, and the current “gold standard” for this process is maturation with TNF-α, IL-1β, IL-6 and PGE₂ used for generating standard DCs (sDC). Several studies indicate that IFN-α might also be important for DC differentiation and maturation. In this study, we tested the effect of IFN-α alone or as addition to the gold standard sDC cocktail. We observed that maturation by IFN-α differs from sDC maturation: The major phenotypic change after IFN-α maturation was dose-dependent up-regulation of CD38 but not CD83, while sDCs expressed the opposite profile with low CD38 and high CD83 expression. Similarly, maturation by Poly I:C leads to CD38high, CD83low DCs indicating a functional relationship between CD38, IFN-α and TLR3. Thus, CD38 appear to be a relevant marker for activation by TLR3 or IFN-α. Addition of IFN-α to the sDC cocktail results in up-regulation of both CD38 and CD83 and improved capacity for induction of autologous T-cell responses despite few other changes in DC phenotype and cytokine secretion. Our observations suggest that IFN-α could be included in maturation protocols for clinical grade DCs used for immunotherapy against cancer and should be included if DCs are used for CD8+ T-cell stimulation in vitro.     

Gene profiles of a human bronchial epithelial cell line after in vitro exposure to respiratory (non-)sensitizing chemicals: Identification of discriminating genetic markers and pathway analysis

Respiratory sensitization is a concern for occupational and environmental health in consumer product development. Despite international regulatory requirements there is no established protocol for the identification of chemical respiratory sensitizers. New tests should be based on mechanistic understanding and should be preferentially restricted to in vitro assays. The major goal of this study was to investigate the alterations in gene expression of human bronchial epithelial (BEAS-2B) cells after exposure to respiratory sensitizers and respiratory non-sensitizing chemicals, and to identify genes that are able to discriminate between both groups of chemicals. BEAS-2B cells were exposed during 6, 10, and 24 h to the respiratory sensitizers ammonium hexachloroplatinate IV, hexamethylene diisocyanate, and trimellitic anhydride, the irritants acrolein and methyl salicylate, and the skin sensitizer 1-chloro-2,4-dinitrobenzene. Overall changes in gene expression were evaluated using Agilent Whole Human Genome 4× 44K oligonucleotide arrays. Fisher Linear Discriminant Analysis was used to obtain a ranking of genes that reflects their potential to discriminate between respiratory sensitizing and respiratory non-sensitizing chemicals. The 10 most discriminative genes were BC042064, A_24_P229834, DOCK11, THC2544911, DLGAP4, NINJ1, PFKM, FLJ10986, IL28RA, and CASP9. Based on the differentially expressed genes, pathway analysis was used to identify possible underlying mechanisms of respiratory sensitization. We demonstrated that in bronchial epithelial cells the canonical PTEN signaling pathway is probably the most specific pathway in the context of respiratory sensitization. Results are indicative that the BEAS-2B cell line can be used as an alternative cell model to screen chemical compounds for their respiratory sensitizing potential.     

Gene profiles of THP-1 macrophages after in vitro exposure to respiratory (non-)sensitizing chemicals: Identification of discriminating genetic markers and pathway analysis

It is recognized that respiratory sensitization is a hazard of high concern. Despite international regulatory requirements there is no established protocol for the identification of chemical respiratory sensitizers. New tests should be based on mechanistic understanding and should be preferentially restricted to in vitro assays. The major goal of this study was to investigate the genetic response of human THP-1 macrophages after contact with respiratory (non-)sensitizers, and to identify genes that are able to discriminate between both groups. THP-1 macrophages were exposed during different time points to 3 respiratory sensitizers, 2 irritants, and 1 skin sensitizer. Gene expression changes were evaluated using Agilent Whole Human Genome arrays. Fisher Linear Discriminant Analysis was used to obtain a ranking of genes that reflects their potential to discriminate between respiratory (non-)sensitizing chemicals. Among the 20 most discriminating genes which were categorized into molecular and biological Gene Ontology (GO) terms, EIF4E, PDGFRB, SEMA7A, and ZFP36L2 could be associated with respiratory sensitization. When categorizing the top-1000 genes into biological GO terms, 24 genes were associated with immune function. Using a pathway analysis tool, platelet-derived growth factor signaling was observed to be activated in THP-1 macrophages in the context of respiratory sensitization.     

Pharmacological differences between once daily and twice daily gentamicin dosage in newborns with suspected sepsis

Objective To evaluate two different regimens for gentamicin administration (once or twice daily) in newborns with suspected sepsis, and the ability of these regimens to achieve recommended serum gentamicin concentrations (SGC) within the therapeutic range. Setting Neonatal intensive care unit. Method We conducted a retrospective study of newborns ≥34 weeks gestational age (GA) admitted with suspected sepsis to the neonatal unit at Stavanger University Hospital from 1st February 2003 to 31st May 2005. During the first period patients received gentamicin 2.5 mg/kg twice daily (n = 62) and during the last period patients received gentamicin 4 mg/kg once daily (n = 73). In both groups, levels of gentamicin were obtained before and after the third given dose. Results Mean peak levels were lower and mean trough levels were higher in the twice daily regimen compared to the once daily regimen (P < 0.001 for both). About 16 newborns in the twice daily regimen had trough levels higher than the recommended level (<2 μg/ml) compared to two children in the once daily regimen (P < 0.001). High peak levels (>10 μg/ml) were achieved in one child in the twice daily regimen compared to eight children in the once daily regimen (P = 0.04). The number of children with a low peak level (<5 μg/ml) was only three and one respectively (n.s). Conclusion In newborns with suspected sepsis, gentamicin 4 mg/kg once daily provided higher peak and lower trough gentamicin levels compared to administering gentamicin 2.5 mg twice daily.     

Complete Genome Sequence and Phylogenetic Relatedness of Hepatitis B Virus Isolates in Papua,Indonesia

Each hepatitis B virus (HBV) genotype and subgenotype is associated with a particular geographic distribution, ethnicity, and anthropological history. Our previous study showed the novel HBV subgenotypes C6 (HBV/C6) and D6 (HBV/D6), based on the S gene sequences of isolates in Papua, Indonesia. The present study investigated the complete genome sequence of 22 strains from Papua and subjected them to molecular evolutionary analysis. A phylogenetic analysis revealed that 9 out of 22 strains were classified as HBV/C6, 3 strains as HBV/D6, and 9 strains as HBV/B3. A particular strain positioned between HBV/B3 and HBV/B5 remained unclassifiable into any known subgenotypes. This strain showed high homology with HBV/C5 from the Philippines in the core region and was thought to have undergone genetic recombination with HBV/C5. Further studies are needed to determine whether this strain belongs to a new subgenotype of HBV/B. Based on the amino acid alignment, HBV/C6 has subgenotype specific variations (G18V and V47M) in the S region. HBV/C6 strains were more closely related in terms of evolutionary distance to strains from the east Asia and Pacific regions than those found in southeast Asia. HBV/D6 strains were most closely related to strains from the Western countries (HBV/D3) rather than those from Asia and Papua New Guinea. In conclusion, we have confirmed by complete sequence analysis that two novel HBV subgenotypes, HBV/C6 and HBV/D6, are prevalent in Papua, Indonesia.Hepatitis B virus (HBV) is an etiological agent of chronic liver disease, including chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma, and this poses major health problems worldwide, especially in Asian Pacific countries (7, 10).HBV strains that infect humans show genetic and antigenic heterogeneity, and eight genotypes, designated A to H, have been identified so far by molecular evolutionary analysis (19). The HBV genotypes have distinct geographical distributions, which are associated with anthropological history (4, 13, 20, 31). Furthermore, previous studies have demonstrated the presence of several subgenotypes within the widely spread genotypes. HBV genotype B (HBV/B) is classified into six subgenotypes, B1 to B6, B1 dominating in Japan, B2 in China and Vietnam, B3 in Indonesia, B4 in Vietnam, B5 in the Philippines, and B6 in the Arctic (3, 16, 23, 24, 26, 27). As for HBV/C, C1 is common in southeast Asia, C2 in east Asia, C3 in Oceania, C4 in Aborigines, and C5 in the Philippines (15, 26). HBV/D has a worldwide distribution, with its highest prevalence in the Mediterranean region, and is classified as D1 to D5 (1, 15, 17). Our previous study revealed novel subgenotypes (HBV/C6 and HBV/D6) based on the S gene sequence of HBV isolates in Papua, Indonesia, where HBV infection is endemic (9).HBV genotyping with the S gene sequence is, in general, consistent with the genotyping of the full genomic sequence, and therefore, HBV genotypes can be assigned based upon S gene sequences (11, 16, 19). Subgenotype classification, however, may not be applicable to some HBV strains on the basis of the S region sequence alone (9, 14, 15). Accordingly, complete genome sequences are more reliable for the analysis of genotype and subgenotype classification for HBV (14). The data on the complete genome sequences of the HBV strains found in Papua are scant. The present study aimed to evaluate the HBV genotypes and subgenotypes present among the Papuan population using complete genome sequences. In addition, the phylogenetic relatedness of HBV strains isolated from Papua was assessed.     

Mpp4 recruits Psd95 and Veli3 towards the photoreceptor synapse

Membrane-associated guanylate kinase (MAGUK) proteins function as scaffold proteins contributing to cell polarity and organizing signal transducers at the neuronal synapse membrane. The MAGUK protein Mpp4 is located in the retinal outer plexiform layer (OPL) at the presynaptic plasma membrane and presynaptic vesicles of photoreceptors. Additionally, it is located at the outer limiting membrane (OLM) where it might be involved in OLM integrity. In Mpp4 knockout mice, loss of Mpp4 function only sporadically causes photoreceptor displacement, without changing the Crumbs (Crb) protein complex at the OLM, adherens junctions or synapse structure. Scanning laser ophthalmology revealed no retinal degeneration. The minor morphological effects suggest that Mpp4 is a candidate gene for mild retinopathies only. At the OPL, Mpp4 is essential for correct localization of Psd95 and Veli3 at the presynaptic photoreceptor membrane. Psd95 labeling is absent of presynaptic membranes in both rods and cones but still present in cone basal contacts and dendritic contacts. Total retinal Psd95 protein levels are significantly reduced which suggests Mpp4 to be involved in Psd95 turnover, whereas Veli3 proteins levels are not changed. These protein changes in the photoreceptor synapse did not result in an altered electroretinograph. These findings suggest that Mpp4 coordinates Psd95/Veli3 assembly and maintenance at synaptic membranes. Mpp4 is a critical recruitment factor to organize scaffolds at the photoreceptor synapse and is likely to be associated with synaptic plasticity and protein complex transport.     

Performance of MRSA ID, a new chromogenic medium for detection of methicillin-resistant Staphylococcus aureus

MRSA ID was evaluated for its ability to identify methicillin-resistant Staphylococcus aureus. A well-defined collection of staphylococci was used (n = 998). The sensitivity after 24 h was 96.4%, increasing to 98.8% after 48 h. The specificity was 98.2% after 24 h and decreased to 89.7% after 48 h.