Geographical distribution of hepatitis C virus genotypes in blood donors:an international collaborative survey

The frequency of infection with the six classified major genotypes of hepatitis C virus (HCV) was investigated in 447 infected volunteer blood donors from the following nine countries: Scotland, Finland, The Netherlands, Hungary, Australia, Egypt, Japan, Hong Kong, and Taiwan. Viral sequences in plasma from blood donors infected with HCV were amplified in the 5'-noncoding region and were typed by restriction fragment length polymorphism analysis. Electrophoresis of DNA fragments produced by cleavage with HaeIII-RsaI and ScrFI-HinfI allowed HCV types 1 (or 5), 2, 3, 4, and 6 to be identified. Further analysis with MvaI-HinfI allowed sequences of the type 5 genotype to be distinguished from sequences of type 1 genotype. Types 1, 2, and 3 accounted for almost all infections in donors from Scotland, Finland, The Netherlands, and Australia. Types 2 and 3 were not found in the eastern European country (Hungary), where all but one of the donors were infected with type 1. Donors from Japan and Taiwan were infected only with type 1 or 2, while types 1, 2, and 6 were found in those from Hong Kong. HCV infection among Egyptians was almost always by type 4. Donors infected with HCV type 1 showed broad serological reactivity with all four antigens of the second generation Chiron RIBA-2 assay (Chiron Corporation, Emeryville, Calif.), while infection with divergent HCV genotypes elicited antibodies mainly reactive to c22-3 and c33c. Reactivities with antibodies 5-1-1 and c100-3 were infrequent and were generally weak, irrespective of the geographical origin of the donor. Because the envelope region of HCV is even more variable than the NS-4 region, it is likely that vaccines based on these proteins need to be multivalent and perhaps specifically adapted for different geographical regions.link_to_subscribed_fulltex

Engineering: Cornell Quarterly, Vol.24, No.2 (Winter 1990): The Promise of Superconductivity

IN THIS ISSUE: Building on a Solid Base: Cornell Research in Superconductivity /2 ... Thin Films: Progress in Superconducting Materials /6 Robert A. Buhrman ... The Power of Magnetic Levitation: I. A Nearly Frictionless Superconducting Bearing Invented at Cornell /13 ... II. Is Magnetic Transportation in the Future? /17 Francis C. Moon ... Innovative Processing of Ceramic Superconductors /23 Rishi Raj ... Superconductors and Accelerators /27 Hasan Padamsee ... Superconductors for Faster Computers /36 J. Peter Krusius ... Making Faster Circuits Using Superconductors /42 Richard C. Compton ... Register /47 ... Faculty Publications /52 ... Letters /5

Engineering: Cornell Quarterly, Vol.18, No.3 (Spring 1983-84): Key to New Technologies

IN THIS ISSUE: Submicron Structures: A Microcosm of Modern Engineering /2 Thomas E. Everhart ... Ultrasmall Features: Key to the Future Development of VLSI Technology /7 J. Peter Krusius ... Small-Scale Physics for Large-Scale Electronic Circuits /12 Jeffrey Frey ... Dry Processing: New Techniques for Etching Submicrometer Structures /16 Edward D. Wolf and Ilesanmi Adesida ... New Techniques for Growing Compound Semiconductors /20 Lester F. Eastman ... Microfabrication for Guided Wave Optics /28 Gregory J. Sonek and Joseph M. Ballantyne ... Superconductors in Microstructures /32 Robert A. Buhrman ... Multidisciplinary Research: Key to Progress at NRRFSS /37 ... Register /41 ... Faculty Publications /4

Engineering: Cornell Quarterly, Vol.23, No.1 (Autumn 1988): A New Thrust in Electronics Research

IN THIS ISSUE: Cornell and JSEP: A New Thrust in a Major Program of Electronics Research /2 ... Growing Crystalline Layers for New High-Speed Electron Devices /4 J. Richard Shealy ... Supercomputer Simulation for Understanding and Designing Ultra-High-Speed Semiconductor Devices /8 J. Peter Krusius, Abdul-Azeez Al-Omar, and Steven R. Weinzierl ... VLSI Arrays for Signal Processing /15 Franklin T. Luk and David E. Schimmel Innovations in Computer Architecture for Real-Time Signal Processing and Other Applications /18 H. C. Torng ... Measuring the Unimaginably Fast: Femtosecond Spectroscopy of Semiconductors and Large Molecules /22 C. L. Tang ... Area Vs. Time: A Tradeoff in a VLSI Computer /26 Gianfranco Bilardi ... Ultrafast Sampling with a Soliton Laser /31 Clifford R. Pollock ... Register /36 ... Faculty Publications /4

Engineering: Cornell Quarterly, Vol.28, No.1 (Autumn 1993): The Electronic Packaging Program

IN THIS ISSUE: The Electronic Packaging Program /2 (The ongoing miniaturization of electronic products challenges engineers to find better ways of putting them together.) ... The Importance of Polymers in Packaging /4 (The advantages of polymers make them indispensable in electronic packaging; overcoming their shortcomings makes for challenging research.) ...Spin-On Oxides for Microelectronics /9 (A technique developed for preparing photoresists can be used to make thin films of high-dielectric-constant oxides for capacitors.) ... Thermal Management of Electronic Packages /20 (Electronic circuits can be damaged by the heat they generate, so thermal engineers are on the case.) ... Dependable Connections: Getting the Signal In and Out /14 (Careful testing improves technologies for making reliable connections between dense arrays of very small contacts.) ... Simulating System Constraints in Computer Packaging /26 (A simulation program makes it possible to compare different packaging options without having to build real prototypes.) ... Register /31 (Three new members join the faculty, six retire.) ... Faculty Publications /3

Platelet-derived Growth Factor Differentially Regulates the Expression and Post-translational Modification of Versican by Arterial Smooth Muscle Cells through Distinct Protein Kinase C and Extracellular Signal-regulated Kinase Pathways*

The synthesis of proteoglycans involves steps that regulate both protein and glycosaminoglycan (GAG) synthesis, but it is unclear whether these two pathways are regulated by the same or different signaling pathways. We therefore investigated signaling pathways involved in platelet-derived growth factor (PDGF)-mediated increases in versican core protein and GAG chain synthesis in arterial smooth muscle cells (ASMCs). PDGF treatment of ASMCs resulted in increased versican core protein synthesis and elongation of GAG chains attached to the versican core protein. The effects of PDGF on versican mRNA were blocked by inhibiting either protein kinase C (PKC) or the ERK pathways, whereas the GAG elongation effect of PDGF was blocked by PKC inhibition but not by ERK inhibition. Interestingly, blocking protein synthesis in the presence of cycloheximide abolished the PDGF effect, but not in the presence of xyloside, indicating that GAG synthesis that results from PKC activation is independent from de novo protein synthesis. PDGF also stimulated an increase in the chondroitin-6-sulfate to chondroitin-4-sulfate ratio of GAG chains on versican, and this effect was blocked by PKC inhibitors. These data show that PKC activation is sufficient to cause GAG chain elongation, but both PKC and ERK activation are required for versican mRNA core protein expression. These results indicate that different signaling pathways control different aspects of PDGF-stimulated versican biosynthesis by ASMCs. These data will be useful in designing strategies to interfere with the synthesis of this proteoglycan in various disease states