Development of a Newborn Screening Program for Critical Congenital Heart Disease (CCHD) in Taipei

BackgroundEarly detection of critical congenital heart disease (CCHD) can significantly reduce morbidity and mortality among newborns. We investigate the feasibility of implementing a community-based newborn CCHD screening program in Taipei.MethodsTwelve birthing facilities in Taipei participated in a trial screening program between October 1, 2013, and March 31, 2014. Newborns underwent pulse oximetry at 24–36 h old, with probes attached to the right hand and one lower limb. Any screening saturation ≥95% in either extremity, with an absolute difference of ≤3% between the right hand and foot, was accepted as a screening pass. A screening result was considered as a fail if the oxygen saturation was <95% at either probe site, on 3 separate occasions, each separated by 30 min or the first result was <95% at either probe site, and any subsequent oxygen saturation measurement was <90%. Public health nurses would follow up all missed or refused cases.ResultsOf the 6,387 live births, 6,296 newborns (coverage rate: 6,296/6,387 = 98.6%) underwent appropriate pulse oximetry screening. Sixteen newborns (0.25%) were reported to have a failed screening result. Five of these screen positive newborns were confirmed with CCHD; two of them were diagnosed solely attributed to the failed screening results. The false-positive rate was 0.18%. Implementing a 6-month screening program for CCHD produced good case detection rate, while using efficient screening and referral systems.ConclusionThis program was successful in integrating screening, referral and public health tracking systems. The protocol outlined in this report could provide a community-based model for worldwide implementation.     

Transduction of c-src coding and intron sequences by a transformation-defective deletion mutant of Rous sarcoma virus.

The mechanism of cellular src (c-src) transduction by a transformation-defective deletion mutant, td109, of Rous sarcoma virus was studied by sequence analysis of the recombinational junctions in three td109-derived recovered sarcoma viruses (rASVs). Our results show that two rASVs have been generated by recombination between td109 and c-src at the region between exons 1 and 2 defined previously. Significant homology between td109 and c-src sequences was present at the sites of recombination. The viral and c-src sequence junction of the third rASV was formed by splicing a cryptic donor site at the 5' region of env of td109 to exon 1 of c-src. Various lengths of c-src internal intron 1 sequences were incorporated into all three rASV genomes, which resulted from activation of potential splice donor and acceptor sites. The incorporated intron 1 sequences were absent in the c-src mRNA, excluding its being the precursor for recombination with td109 and implying that initial recombinations most likely took place at the DNA level. A potential splice acceptor site within the incorporated intron 1 sequences in two rASVs was activated and was used for the src mRNA synthesis in infected cells. The normal env mRNA splice acceptor site was used for src mRNA synthesis for the third rASV.     

Free radicals and carcinogenesis. Some properties of the nitroxyl free radicals produced by covalent binding of 2-nitrosofluorene to unsaturated lipids of membranes.

We have demonstrated that the carcinogen 2-nitrosofluorene (NOF) reacts with rat liver microsomal membranes to produce a nitroxyl free radical form of the carcinogen, designated N-?-LAF. We conclude that NOF adds to the double bond of the membrane lipids in a pseudo Diels-Alder reaction. This conclusion is based on studies involving 2,3-dimethyl-2-butene and NOF. NOF reacts with this simple unsaturated hydrocarbon to produce a stable nitroxyl free radical in a pseudo Diels-Alder reaction. NOF adds to liposomes formed from lipids extracted from the rat liver microsomes to produce a free radical identical to that produced with microsomes. NOF forms the same amount of N-?-LAF at the same rate in heated microsomes as in unheated microsomes. The observations indicate the involvement of only the lipid fraction in the reaction of NOF with membranes. The amount of N-?-LAF formed increases hyperbolically in microsomes and liposomes as a function of NOF added. The amount of N-?-LAF formed reaches a maximum, at which point the amount of free radical present is about 1% of both the amount of NOF added and the amount of phospholipid present. The half-maxima of the amount of N-?-LAF formed occurs at 50 μm NOF in liposomes but at 100 μm in microsomes. The electron spin resonance spectrum of N-?-LAF indicates that this nitroxyl free radical is in a rigidly fixed position in the membrane. N-?-LAF is reduced by NADPH. There appears to be a direct chemical reduction as well as an enzyme-mediated mechanism involving NADPH-potentiated electron flow in microsomes. The reduced compound is reoxidized by ferricyanide added to microsomal membranes.     

Prior exposure to uninfected mosquitoes enhances mortality in naturally-transmitted West Nile virus infection

Background

The global emergence of West Nile virus (WNV) has highlighted the importance of mosquito-borne viruses. These are inoculated in vector saliva into the vertebrate skin and circulatory system. Arthropod-borne (arbo)viruses such as WNV are transmitted to vertebrates as an infectious mosquito probes the skin for blood, depositing the virus and saliva into the skin and circulation. Growing evidence has demonstrated that arthropod, and recently mosquito, saliva can have a profound effect on pathogen transmission efficiency, pathogenesis, and disease course. A potentially important aspect of natural infections that has been ignored is that in nature vertebrates are typically exposed to the feeding of uninfected mosquitoes prior to the mosquito that transmits WNV. The possibility that pre-exposure to mosquito saliva might modulate WNV infection was explored.

Principal Findings

Here we report that sensitization to mosquito saliva exacerbates viral infection. Prior exposure of mice to mosquito feeding resulted in increased mortality following WNV infection. This aggravated disease course was associated with enhanced early viral replication, increased interleukin-10 expression, and elevated influx of WNV-susceptible cell types to the inoculation site. This exacerbated disease course was mimicked by passive transfer of mosquito-sensitized serum.

Significance

This is the first report that sensitization to arthropod saliva can exacerbate arthropod-borne infection, contrary to previous studies with parasite and bacteria infections. This research suggests that in addition to the seroreactivity of the host to virus, it is important to take into account the immune response to vector feeding.     

A highly potent peptide analgesic that protects against ischemia-reperfusion-induced myocardial stunning

We recently discovered an opioid peptide analgesic, 2',6'-dimethyltyrosine (Dmt)-D-Arg-Phe-Lys-NH(2) ([Dmt(1)]DALDA), that can protect against ischemia-induced myocardial stunning. In buffer-perfused hearts, 30-min global ischemia followed by reperfusion resulted in a significant increase in norepinephrine (NE) overflow immediately upon reperfusion and significant decline in contractile force (45%). Pretreatment with [Dmt(1)]DALDA before ischemia completely abolished myocardial stunning and significantly reduced NE overflow (68%). In contrast, pretreatment with morphine before ischemia only provided brief protection against myocardial stunning and no reduction in NE overflow. [Dmt(1)]DALDA inhibited [(3)H]NE uptake into cardiac synaptosomes in vitro (IC(50) = 3.9 microM), whereas morphine had no effect. Surprisingly, protection against myocardial stunning was apparent even when hearts were perfused with [Dmt(1)]DALDA only upon reperfusion, whereas reperfusion with morphine had no effect. Binding studies with [(3)H][Dmt(1)]DALDA revealed no high-affinity specific binding in cardiac membranes, suggesting that the cardioprotective actions of [Dmt(1)]DALDA are not mediated via opioid receptors. These findings suggest that [Dmt(1)]DALDA is a potent analgesic that may be useful for myocardial stunning resulting from cardiac interventions or myocardial ischemia.     

Varicella-Zoster Virus (VZV) ORF32 Encodes a Phosphoprotein That Is Posttranslationally Modified by the VZV ORF47 Protein Kinase

Varicella-zoster virus (VZV) encodes five gene products that do not have homologs in herpes simplex virus. One of these genes, VZV open reading frame 32 (ORF32), is predicted to encode a protein of 16 kDa. VZV ORF32 protein was shown to be phosphorylated and located in the cytosol of virus-infected cells. Antibody to ORF32 protein immunoprecipitated 16- and 18-kDa phosphoproteins from VZV-infected cells. Since VZV encodes two protein kinases that might phosphorylate ORF32 protein, immunoprecipitations were performed with cells infected with VZV mutants unable to express either of the viral protein kinases. Cells infected with VZV unable to express the ORF66 protein kinase contained both the 16- and 18-kDa ORF32 phosphoproteins; however, cells infected with the VZV ORF47 protein kinase mutant showed only the 16-kDa ORF32 phosphoprotein. Treatment of [³⁵S]methionine-labeled proteins with calf intestine alkaline phosphatase resulted in a decrease in size of the ORF32 proteins from 16 and 18 kDa to 15 and 17 kDa, respectively. VZV unable to express ORF32 protein replicated in human melanoma cells to titers similar to those seen with parental virus; however, VZV unable to express ORF32 was impaired for replication in U20S osteosarcoma cells. Thus, VZV ORF32 protein is posttranslationally modified by the ORF47 protein kinase. Since the VZV ORF47 protein kinase has recently been shown to be critical for replication in human fetal skin and lymphocytes, its ability to modify the ORF32 protein suggests that the latter protein may have a role for VZV replication in human tissues.