High doses of a helper-dependent adenoviral vector yield supraphysiological levels of alpha1-antitrypsin with negligible toxicity

Optimal gene therapy for many disorders will require efficient transfer to cells in vivo, high-level and long-term expression, and tissue-specific regulation, all in the absence of significant toxicity or inflammatory responses. While recombinant adenoviral vectors are efficient for gene transfer to hepatocytes, their usefulness is limited by short duration of expression related, at least in part, to immune responses to viral proteins and by a low capacity for foreign DNA. A number of systems have been developed for producing adenoviral vectors devoid of all viral coding sequences. Using AdSTK109, a vector lacking all viral coding sequences and carrying the complete human alpha1-antitrypsin (hAAT) genomic DNA locus, we have demonstrated sustained expression for longer than 10 months in mice. Utilizing high doses of this vector for hepatic gene transfer in mice, we find that supraphysiological levels of hAAT can be achieved without hepatotoxicity.     

Efficacy of novel antimicrobials against clinical isolates of opportunistic amebas

Using atomic force microscopy (AFM), we have investigated neutron-induced DNA double-strand breaks in plasmids in aqueous solution. AFM permits direct measurement of individual DNA molecules with an accuracy of a few nanometers. Furthermore, the analysis of the DNA fragment size distribution is non-parametric, whereas other methods are dependent on the model. Neutron irradiation of DNA results in the generation of many short fragments, an observation not made for damage induced by low-LET radiation. These data provide clear experimental evidence for the existence of clustered DNA double-strand breaks and demonstrate that short DNA fragments may be produced by such radiations in the absence of a nucleosomal DNA structure.     

Incorporation of fowl plague virus hemagglutinin into murine leukemia virus particles and analysis of the infectivity of the pseudotyped retroviruses

We describe retrovirus particles carrying the fowl plague virus (FPV) hemagglutinin (HA). When expressed in cells providing Moloney murine leukemia virus (MoMLV) Gag and Pol proteins and a lacZ retroviral vector, FPV HA was found to be efficiently expressed, correctly processed, and stably incorporated into retroviral particles. HA-bearing retroviruses were infectious with a wide host range and were only 10-fold less infectious than retroviruses carrying wild-type MLV retroviral envelopes. We also coexpressed HA proteins in retroviral particles with chimeric MoMLV-derived envelope glycoproteins that efficiently retarget virus attachment but are only weakly fusogenic. Our results suggest that HA can in some cases enhance the fusion ability of these retroviral particles, depending on the cell surface molecule that is used as a receptor.     

Neurologic consultation practice in a general hospital of a rural area

The purpose of this ongoing study is to evaluate the safety and efficacy of new minimally invasive pervaginam cystourethropexy and sling procedures for the treatment of female genuine stress urinary incontinence. A total of 75 women (mean age, 52.8 years) underwent either a cystourethropexy or a sling procedure. A miniature bone anchor and a staple-like bone anchor driver were used for the fixation of periurethral tissue or a xenogenic sling to the pubic bone. With a mean follow-up of eight months, 61 patients (82%) were completely cured of stress incontinence, 10 (14%) reported a more than 50% decrease in pad usage, and 4 patients showed failure early following surgery. The exclusively pervaginam cystourethropexy and sling procedures are minimally invasive, safe, and effective. Further experience and longer follow-up are necessary to establish their role in the treatment of women with stress urinary incontinence.     

Dystrophia myotonica

The authors present two cases of myotonic dystrophy (Steinert's disease) with cardiac involvement in young adults. They point out the rareness of this disease, the multisystemic involvement and also the diagnostic problems in the absence of the classic clinical picture.     

Tracing prehistoric migrations by the viruses they carry: human T-cell lymphotropic viruses as markers of ethnic relationships

Three reasons that HTLV-I and HTLV-II would not be expected to trace human migrations over extended time periods have been examined, and none has proven fatal to the theory. Transmission of the HTLVs (human T-cell lymphotropic viruses) in endemic settings highly depends on passage through breast milk, and this creates a pattern of distribution similar to that of mitochondrial DNA. The HTLVs probably evolve at variable rates, making the extent of sequence change a poor tool for dating human migrations. However, qualitative relationships between the sequence of human population separations and virus strain may be more regular. The uniqueness of viruses as markers of human relationship gives this method special value as a source of novel ideas regarding human movements and as independent confirmation of migration hypotheses that have been based on more conventional methods.     

Hepatitis B virus infection, hepatitis B vaccine, and hepatitis B immune globulin

Hepatitis B virus (HBV) infection is a major health problem in the United States; in 1995, approximately 128,000 cases occurred. Transmission of HBV occurs primarily by blood exchange (eg, by shared needles during injection drug use) and by sexual contact. Persons infected early in life are much more likely to become chronically infected than those infected during adulthood: as many as 90% of infants infected perinatally develop chronic infection and up to 25% will die of HBV-related chronic liver disease as adults. Clinical signs of acute hepatitis occur in about 50% of infected adults but in only 5% of infected preschool-aged children. In the United States, hepatitis B vaccine is currently made by recombinant DNA technology using baker's yeast. Preexposure vaccination results in protective antibody levels in almost all infants and children (> 95%) and healthy adults younger than 40 years of age (> 90%). The most common adverse event following administration of hepatitis B vaccine is pain at the injection site, which occurs in 13% to 29% of adult and 3% to 9% of children. A comprehensive hepatitis B vaccination policy is now recommended that includes (1) routine infant vaccination; (2) catch-up vaccination of 11- to 12-year-olds who were not previously vaccinated; (3) catch-up vaccination of young children at high risk for infection; (4) vaccination of adolescents and adults based on lifestyle or environmental, medical, and occupational situations that place them at risk; and (5) prevention of perinatal HBV infection.     

Hexon-only binding of VP26 reflects differences between the hexon and penton conformations of VP5, the major capsid protein of herpes simplex virus

VP26 is a 12-kDa capsid protein of herpes simplex virus 1. Although VP26 is dispensable for assembly, the native capsid (a T=16 icosahedron) contains 900 copies: six on each of the 150 hexons of VP5 (149 kDa) but none on the 12 VP5 pentons at its vertices. We have investigated this interaction by expressing VP26 in Escherichia coli and studying the properties of the purified protein in solution and its binding to capsids. Circular dichroism spectroscopy reveals that the conformation of purified VP26 consists mainly of beta-sheets (approximately 80%), with a small alpha-helical component (approximately 15%). Its state of association was determined by analytical ultracentrifugation to be a reversible monomer-dimer equilibrium, with a dissociation constant of approximately 2 x 10(-5) M. Bacterially expressed VP26 binds to capsids in the normal amount, as determined by quantitative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Cryoelectron microscopy shows that the protein occupies its usual sites on hexons but does not bind to pentons, even when available in 100-fold molar excess. Quasi-equivalence requires that penton VP5 must differ in conformation from hexon VP5: our data show that in mature capsids, this difference is sufficiently pronounced to abrogate its ability to bind VP26.     

The incompetent palatopharynegeal sphincter. President''s address

The effect of red (660 nm) and far-red (730 nm) light on the stability of the yeast Candida guilliermondii to lethal u.v. radiation has been studied. Reactivation and protection were exhibited for 30 min after treatment with red light and were abolished by far-red exposure applied within this time period. The temperature dependence of the reactivation effect was also studied. The data obtained showed that the properties of recovery and protection against u.v. exposure are associated with the phytochrome system of the yeast.     

Occurrence of gastric ulcer after Nissen fundoplication

Of 160 patients who underwent Nissen fundoplication for treatment of symptomatic peptic reflux esophagitis, five patients (3.1%) developed gastric ulcers. Four of these five patients experienced the "gas-bloat" syndrome. All ulcers were located on the lesser curvature of the stomach. Analyses of our experience with use of various types of hiatal hernia repair suggests that creation of the valvuloplastic mechanism unique to the Nissen procedure may be of etiologic significance in the development of gastric ulcers following this procedure.