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Summary Warrego and Mitchell River viruses form the Warrego serological group of orbiviruses. Their double-stranded RNA genomes differ in molecular weight and in thermal denaturation profiles.

We studied the effect of aging on cardiac hypertrophy and action potential duration (APD) in nor-motensive male WAG/Rij rats and evaluated the role of the renin-angiotensin system (RAS) in these effects. Cardiac hypertrophy occurs in 30-month-old rats, as indicated by an increase in heart weight, and APD gradually increases with aging in the epicardial region of the right and the left ventricle. Short-term treatment (1 month) with the angiotensin-converting enzyme inhibitor (ACEI) perindopril prevented age-related increase in heart weight/body weight ratio independent of its antihyperten-sive effects, but did not prevent changes in APD in 30-month-old rats. Our results show a dissociation of changes in cardiac mass from changes in APD during aging. The effect of ACEI on hypertrophy may be due in part to a direct angiotensin effect on cellular growth. Changes in APD are not related to hypertrophy but rather to the process of aging.

Intraocular metallic-appearing foreign bodies in the anterior segment were seen in six eyes after cataract extraction by two-handed phacoemulsification. These fragments produced no symptoms and had no clinically significant effect on visual function. Similar-appearing foreign bodies were experimentally produced by applying ultrasound power with a phacoemulsification handpiece to the surface of a cyclodialysis spatula in vitro. Microscopic examination of the phaco handpiece tip and cyclodialysis spatulas revealed numerous surface irregularities, suggesting a possible source of these fragments. These results suggest that instrument touch during phacoemulsification may be the cause of the fragments. Long-term follow-up of these patients is required to determine the overall effect of the fragments.

Viruses with genomes consisting of 12 segments of double-stranded (ds) RNA were isolated from mosquito pools collected in indonesia in 1980 and 1981. The genome segments of 11 virus isolates exhibited two distinct electrophoretic patterns in agarose gels, and the viruses probably represent distinct groups of Coltiviruses. Ten of the 11 virus isolates produced recognizably similar PAGE profiles of two groups of 6 segments (6-6) with 3 distinct profile variants, and the remaining virus isolate displayed a unique 6-5-1 profile. These profiles were distinct from that of Colorado tick fever (CTF) virus RNA. The genetic relatedness of the isolates was examined by RNA-RNA hybridization. The viruses with a 6-6 profile were closely related in the majority of their segments, with segments 7, 11, and 12 being variant; and segment 9 the most divergent. The segments of the virus with the unique PAGE profile (6-5-1)did not cross-hybridize with any of the other viruses. Similarly, RNA from virus isolates from Indonesian did not cross-hybridize with the segments of CTF virus. These data indicate that two additional genotypes are present in the Coltivirus genus. Copyright 1993, 1999 Academic Press

An antibody against the Escherichia coli-expressed RNA polymerase of foot-and-mouth disease virus (FMDV) reacts with the virus in ELISA and radioimmunoprecipitation experiments and with a protein of the disrupted virus particle in an immunoblot analysis. Treatment of the virus with trypsin, which cleaves capsid protein VP1 and a 56-kDa polypeptide present in trace amount in the particles, reduces the level of the reaction in ELISA and radioimmunoprecipitation and eliminates the immunoblot reaction. Electron microscopy showed that only approximately 20% of the virus particles reacted with the anti-polymerase antibody, whereas most reacted with an antibody against the immunodominant G-H loop of the virus. In the presence of ammonium ions, the expressed polymerase degrades the RNA of the virus into molecules sedimenting at approximately 12 S, indicating that it can act as a hydrolytic as well as a polymerizing enzyme. Moreover, the RNA in trypsin-treated virus particles is degraded when incubated at 37 degrees C, suggesting that the cleaved 56-kDa protein still possesses hydrolytic activity. In addition, the anti-polymerase antibody, which inhibits the polymerase activity of the E. coli-expressed protein, also partially inhibits the hydrolytic activity of the previously described endonuclease of the virus particle, suggesting that this enzyme is identical with the polymerase or forms part of it.

The analysis of several isolates of foot-and-mouth disease virus by RNase T1 fingerprinting of the 32P-labeled RNA is described. It has been shown that use of the 35S induced RNA instead of the virus particle RNA has two advantages. (i) About 40 times more radioactivity is incorporated into the induced RNA. (ii) The RNA can be prepared much more rapidly, thus increasing the value of the technique in rapid diagnosis. One-dimensional maps, in which the RNase T1 oligonucleotides are separated according to size, have been shown to provide a valuable screening method for distinguishing between viruses. Those viruses giving similar one-dimensional maps also gave similar two-dimensional maps. The value of using the length of the polycytidylic acid tract of foot-and-mouth disease virus as a diagnostic tool is also discussed.

Thirteen strains of dengue type 1 were isolated from the lymphocyte fractions of 69 acute phase blood samples collected at Thursday Island Hospital during 1981 and 1982. One further strain of type 1 was isolated from 7 blood samples despatched by air from Cairns Base Hospital during 1982. Four of these Australian isolates representing the beginning, middle, and end of the epidemic were examined by restriction enzyme mapping and were found to be identical for the nine restriction enzymes used. The maps differed from those derived from two Malaysian dengue type 1 strains isolated during the epidemic of 1981–82 in that country. This suggests reliance on serological typing to establish global circulation patterns of epidemic dengue is insufficient and that more specific methods such as genome mapping are useful.

Summary Uveitis is an extraintestinal complication of ulcerative colitis and Crohn's disease. In most cases, its course parallels that of the underlying bowel disease and improves with its therapy. Occasionally, the two processes are not synchronous. In either case, the uveitis has usually been considered to be dependent on the presence of the colon. This report describes a patient who developed uveitis shortly after colectomy and ileal-rectal sleeve anastomosis for ulcerative colitis, indicating that the continuing presence of the colonic mucosa is not necessary for development of the associated ocular inflammation.

Congenital microgastria is an extremely rare anomaly in which fetal rotation of the stomach fails and the greater and lesser curvatures do not develop (Caffey, 1956). Although macroscopic differentiation into fundus, body, antrum and pyloric canal does not occur, the present case illustrates that histological differentiation of gastric cell types is normal. The typical radiological features of the disorder are illustrated.

Two bluetongue virus (BTV) serotypes isolated in Australia and two selected reassortants derived from cells coinfected with these viruses have been used to identify the gene coding for the virus hemagglutinin. The parent viruses had characteristic hemagglutination patterns: BTV type 20 agglutinated sheep erythrocytes only; and BTV type 21 agglutinated sheep, bovine, human, and goose erythrocytes. Analysis of the two virus clones that had reassorted in genes coding for the outer capsid polypeptides demonstrated that hemagglutination and hemagglutination inhibition are functions associated with the outer capsid protein (VP2), which is encoded by genome segment 2.

Recent reports1–4have described “yeast-like microfossils” (Isuasphaera isua Pflug2) in 3,800-Myr old5metaquartzites from the Isua supracrustal belt of south-west Greenland. A biogenic interpretation of these objects is inconsistent with the tectonic history of the Isua region6–8, with the petrology of the metaquartzites, and with the morphology of the microstructures themselves. The putative microfossils are indistinguishable from limonite-stained fluid inclusions: microstructures which are demonstrably inorganic and post-depositional in origin. As such, we contend here that these objects should not be regarded as evidence of early Archaean life forms.

Slit-lamp examinations of patients confined to wheelchairs is no easy feat. For those who occasionally find themselves in this position, we recommend the following maneuver.

TO THE EDITOR. —Wessely immune rings of the cornea have been described to occur after infectious corneal ulcers. These rings are composed of polymorphonuclear leukocytes, which collect in a discrete circular region of complement activation around the antigenic entry site. It has long been accepted both experimentally and clinically that the antigenantibody-mediated or classical pathway of complement activation results in a visible Wessely ring ten to 14 days after infection. More recently, Mondino et al1 have shown in an animal model that the properdin-mediated or alternate pathway of complement activation exhibits ring formation one to two days after injection of Pseudomonas aeruginosa or Pseudomonas endotoxin. Additionally, Mondino et al2 have proved that properdin can be found in the limbus of normal human corneas.However, to our knowledge, a human correlate of immune ring formation within the time course of properdin-mediated complement cleavage has yet to be described in

The sintering of (La0.8Sr0.2)0.98MnO3(LSM-20) solid oxide fuel cell cathodes (in the temperature range of 1050–1200°C) on anode-supported cells utilizing a Ni–yttria-stabilized zirconia (YSZ) anode and a thin YSZ electrolyte (<10μmthickness) revealed the need for a protective ceria interlayer to prevent a detrimental interaction between the YSZ and the LSM. The interaction, however, was not the typically assumed formation of insulating La- and Sr-zirconate, but rather the result of Ni diffusion from the anode through the YSZ electrolyte and into the LSM, resulting in coarsening and increased densification of the LSM microstructure. The protective Ce0.8Sm0.2O1.9layers at the cathode/electrolyte interface were effective in blocking the Ni diffusion. As an alternative to the use of a protective ceria interlayer, the presence of YSZ in the cathode material was able to suppress the coarsening of LSM, thereby significantly improving the electrochemical performance.

This paper reports the reliability and validity of the Health Professional-Geriatric Patient Interaction Behavior Rating Code, an observational instrument that is used to quantify the interpersonal behaviors of health professionals in the care of the geriatric patient. Fifteen behavioral factors, deemed by experts as indicative of positive interacting style and identified through a literature review, were condensed into 10 operationally defined behavioral categories.