Prolonged gene expression in mouse lung endothelial cells following transfection with Epstein-Barr virus-based episomal plasmid

The development of a strategy to deliver a gene to pulmonary endothelium will be useful for gene function study and for pulmonary gene therapy. Cationic lipidic vectors are efficient in gene transfer to pulmonary endothelium via the vascular route; however, gene expression is transient and lasts for only a few days. In this study, we show that pulmonary gene transfer via cationic lipidic vectors can be significantly improved using an Epstein-Barr virus (EBV)-based expression plasmid. Systemic administration of cationic liposomes followed by the EBV-based plasmid led to gene expression in the lung that lasted for more than 3 weeks. Prolonged and high levels of gene expression can also be obtained in primary mouse lung endothelial cells (MLEC) following lipofection with an EBV-based plasmid. These results suggest the utility of this gene transfer protocol in studying the expression of cloned genes in lung endothelial cells and in pulmonary gene therapy.

[Synthesis and bioaction of 2-alkyl-4(1H)-quinolone]

Five quinolone alkaloids (IVa, Va, c, d, g) including two new compounds (IVa, Vc) from Evodia rutaecarpa and nine analogs are synthesized in good yield by using acid-catalyzed condensation of a series of 3-oxoalkkanoic acid esters with aniline and further methylized with methyl iodide. The other analogue Vh is prepared through the reaction of lithium enolate methyl ketone with N-methylisatoic anhydride. Eight compounds (IVa, d, f; Vb, c, d, f, h) were synthesized for the first time. Pharmacological studies showed that these compounds have vasoconstriction inhibiting and antiulcer effects. Compound IVb also has cytotoxic effect.

Gene therapy progress and prospects: nonviral vectors

The success of gene therapy is largely dependent on the development of the gene delivery vector. Recently, gene transfection into target cells using naked DNA, which is a simple and safe approach, has been improved by combining several physical techniques, for example, electroporation, gene gun, ultrasound and hydrodynamic pressure. Chemical approaches have been utilized to improve the efficiency and cell specificity of gene transfer. Novel gene carrier molecules, which facilitate DNA escape from the endosome into the cytosol, have been developed. Several functional polymers, which enable controlled release of DNA in response to an environmental change, have also been reported. Plasmids with reduced number of CpG motifs, the use of PCR fragments and the sequential injection method have been established for the reduction of immune response triggered by plasmid DNA. Construction of a long-lasting gene expression system is also an important theme for nonviral gene therapy. To date, tissue-specific expression, self-replicating and integrating plasmid systems have been reported. Improvement of delivery methods together with intelligent design of the DNA itself has brought about large degrees of enhancement in the efficiency, specificity and temporal control of nonviral vectors.

Preliminary findings of adult health screening under national health insurance in Taiwan

OBJECTIVES

To provide baseline values of health elated parameters for the Taiwanese population.

METHODS

A systematic sample of 9016 out of 692,311 persons undergoing health check-ups is analyzed and described, and compared to a similar survey undertaken ten years ago. Some physical indices and lab tests exhibited significant age and sex related differences.

RESULTS

The prevalence of groups of diseases, and the distribution of test results by age and sex are reported and compared to other studies.

CONCLUSIONS

Compared to the survey conducted ten years ago, Taiwanese adults are taller and heavier, but not necessarily healthier.

Electric gene transfer to the liver following systemic administration of plasmid DNA

Recently, there has been an increasing level of interest in electroporation for gene delivery due to the site-specific nature of the delivery, as well as the high efficiency of the method. Electroporation involves the application of a pulsed electric field to cells to enhance cell permeability, resulting in the transit of exogenous polynucleotide across the cytoplasmic membrane. Electroporation is traditionally performed by locally injecting DNA to the site of interest followed by the application of electric field. Compared with the local injection of plasmid DNA to the liver, systemic injection has the advantage of delivering genes to more hepatocytes. We describe here a method for efficient gene transfer to the liver by electroporation following tail vein administration of the naked DNA. The cells expressing the reporter gene are more broadly distributed with this systemic injection, as compared with direct injection.

Engineered collagen-PEO nanofibers and fabrics

Type I collagen-PEO fibers and non-woven fiber networks were produced by the electrospinning of a weak acid solution of purified collagen at ambient temperature and pressure. As determined by high-resolution SEM and TEM. fiber morphology was influenced by solution viscosity, conductivity, and flow rate. Uniform fibers with a diameter range of 100-150 nm were produced from a 2-wt% solution of collagen-PEO at a flow rate of 100 microl min(-1). Ultimate tensile strength and elastic modulus of the resulting non-woven fabrics was dependent upon the chosen weight ratio of the collagen-PEO blend. 1H NMR dipolar magnetization transfer analysis suggested that the superior mechanical properties, observed for collagen-PEO blends of weight ratio 1:1, were due to the maximization of intermolecular interactions between the PEO and collagen components. The process outlined herein provides a convenient, non-toxic, non-denaturing approach for the generation collagen-containing nanofibers and non-woven fabrics that have potential application in wound healing, tissue engineering, and as hemostatic agents.

[Studies on synthesis and bioactivity of 2-alkenyl-4(1H)-quinolone]

Three 2-alkenyl-4(1H)-quinolone compounds(I-III) were synthesized by two methods. III is a new compound from Evodia rutaecarpa and was synthesized through the reaction of the aldehyde intermediate(5) with Wittig reagent. The other two compounds were synthesized for the first time. These compounds showed vasodilating and antibacteria effects in pharmacological tests.

Stable target-sensitive immunoliposomes

Interaction of immunoliposomes composed of dioleoylphosphatidylethanolamine (DOPE) (80%), dioleoylphosphatidic acid (DOPA) (20%), and a small amount of specific antibody with Herpes Simplex virus (HSV) were studied by detecting the immune-dependent lysis of liposomes. DOPA was used as the principal stabilizer of the immunoliposomes. Antibodies conjugated with N-glutarylphosphatidylethanolamine or oxidized GM1 served as the target-specific ligands of immunoliposomes. These immunoliposomes (d = 160-180 nm) were stable for at least one month when stored at 4 degrees C. However, they undergo a rapid aggregation and lysis reaction in the presence of a membrane-bound target such as intact HSV virions. We have also employed epitope peptide-containing liposomes (target liposomes) to mimic the virus and showed that the immunoliposomes could be aggregated and lysed by the target liposomes in an antigen-dependent manner. Immunoliposome lysis could be accelerated by increasing the incubation temperature to 60-70 degrees C. No immunoliposome lysis was observed if the target liposomes were absent, indicating the prolonged stability of the immunoliposomes. Liposome lysis was always accompanied by liposome aggregation. However, the aggregation-induced liposome destabilization is unique to the HII phase-forming lipids such as DOPE. DOPC-containing immunoliposomes did not lyse despite the fact that massive liposome aggregation had taken place.

A demonstration of a 1:1 correspondence between chiasma frequency and recombination using a Lolium perenne/Festuca pratensis substitution

A single chromosome of the grass species Festuca pratensis has been introgressed into Lolium perenne to produce a diploid monosomic substitution line 2n = 2x = 14. The chromatin of F. pratensis and L. perenne can be distinguished by genomic in situ hybridization (GISH), and it is therefore possible to visualize the substituted F. pratensis chromosome in the L. perenne background and to study chiasma formation in a single marked bivalent. Recombination occurs freely in the F. pratensis/L. perenne bivalent, and chiasma frequency counts give a predicted map length for this bivalent of 76 cM. The substituted F. pratensis chromosome was also mapped with 104 EcoRI/Tru91 and HindIII/Tru91 amplified fragment length polymorphisms (AFLPs), generating a marker map of 81 cM. This map length is almost identical to the map length of 76 cM predicted from the chiasma frequency data. The work demonstrates a 1:1 correspondence between chiasma frequency and recombination and, in addition, the absence of chromatid interference across the Festuca and Lolium centromeres.

Molecular epidemiology of TTV-like mini virus in Norway

TT virus (TTV), the first human circovirus to be discovered, appears to be present in most people; less is known about the prevalence of the related TTV-like mini virus (TLMV). A sensitive nested PCR, specific for TLMV, detected the virus in 48% of 201 sera (Norwegian blood donors) previously found to have a 90% prevalence of TTV. More samples were either positive for both or negative for both viruses than what would have been expected from a random distribution (p = 0.08). Sequence analysis revealed considerable heterogeneity of Norwegian TLMV as compared to international sequences, suggesting that TLMV is efficiently dispersed in human populations.

Haemophilus influenzae type b meningitis with subdural effusion: a case report

Haemophilus influenzae type b causes invasive infection in children under 2 years of age. The disease may be complicated with hearing impairment, lowered learning ability, and other neurologic sequelae. The incidence of invasive H. influenzae type b has declined dramatically after the introduction of routine administration of protein-conjugated H. influenzae type b vaccine in the United States and some other countries. Because of its low incidence in Taiwan, many clinicians are not familiar with the initial symptoms and management of H. influenzae type b. This case report describes a 7-month-old H. influenzae type b meningitis patient who had initial presentations of prolonged intermittent fever and vague neurologic signs. Left peripheral facial palsy with hearing loss in left ear and bilateral frontal subdural effusion developed during the first 5 days of cefotaxime therapy. Betamethasone was then given for 4 days to relieve the severe inflammation. Drug-induced fever was observed after 11 days of antibiotic use and subsided with prednisolone treatment. Left ear hearing impairment persisted during the follow-up period, but the children did not experience other significant development delay.

Preliminary Findings of Adult Health Screening under National Health Insurance in Taiwan

Objectives: To provide baseline values of health elated parameters for the Taiwanese population.

Methods: A systematic sample of 9016 out of 692,311 persons undergoing health check-ups is analyzed and described, and compared to a similar survey undertaken ten years ago. Some physical indices and lab tests exhibited significant age and sex related differences.

Results: The prevalence of groups of diseases, and the distribution of test results by age and sex are reported and compared to other studies.

Conclusions: Compared to the survey conducted ten years ago, Taiwanese adults are taller and heavier, but not necessarily healthier.

Assays of methylenetetrahydrofolate reductase and methionine synthase activities by monitoring 5-methyltetrahydrofolate and tetrahydrofolate using high-performance liquid chromatography with fluorescence detection

We developed a method for assays of methylenetetrahydrofolate reductase and methionine synthase activities by monitoring their products of 5-methyltetrahydrofolate (5-CH(3)-H(4)folate) and tetrahydrofolate (H(4)folate) directly, using high-performance liquid chromatography with fluorescence detection. Folate derivatives and enzymes were stable in the assay process. No reagents in the assay mixture were found to disturb the separation and detection of both H(4)folate and 5-CH(3)-H(4)folate in our assay system. The detection limit of this method was less than 20 nM H(4)folate or 5-CH(3)-H(4)folate in the enzyme assay system. This analytical method, therefore, has a sensitivity high enough to obtain accurate parameters of Michaelis-Menten kinetics and for assays of crude extracts from various biological samples. In addition, the analytical procedure is very simple and economical; it may be a useful tool for studying methylenetetrahydrofolate reductase and methionine synthase activities.

Pigment epithelium-derived factor (PEDF) in neuroblastoma: a multifunctional mediator of Schwann cell antitumor activity

Neuroblastoma is notable for its cellular heterogeneity and unpredictable outcome. Tumors are a variable mixture of primitive malignant neuroblasts, more differentiated ganglionic cells, Schwann and endothelial cells. Although often fatal, neuroblastomas can spontaneously regress, possibly due to favorable autocrine and paracrine interactions among these cells. Here, pigment epithelium-derived factor (PEDF), a potent inhibitor of angiogenesis and inducer of neural differentiation, is shown to be produced by ganglionic cells and Schwann cells, but not by more primitive tumor cells. Although undifferentiated neuroblastoma tumor cell secretions were angiogenic primarily due to vascular endothelial growth factor, secretions of Schwann cells were anti-angiogenic due to PEDF. In addition, PEDF was the major factor responsible for Schwann cell’s ability to induce tumor cell differentiation in vitro and recombinant PEDF had the same effect in vitro and in vivo. Both the growth and the survival of Schwann cells were enhanced by PEDF. Thus PEDF may serve as a multifunctional antitumor agent in neuroblastomas, inhibiting angiogenesis while promoting the numbers of Schwann cells and differentiated tumor cells that in turn produce PEDF, suggesting that its clinical administration could stimulate a multifaceted antitumor feedback loop with the potential to limit and possibly regress tumor growth.