Prognostic significance of specific magnetic resonance imaging features in canine nasal tumours treated by radiotherapy.

OBJECTIVES: To investigate the prognostic significance of the magnetic resonance (MR) findings of meningeal hyperintensity of the olfactory bulbs and tumour extension into the caudal nasal recess (CNR) in dogs with nasal tumours treated by radiotherapy. METHODS: MR images of 41 dogs with nasal tumours treated with radiotherapy were reviewed. The occurrence of neurological signs and survival of patients with and without meningeal hyperintensity of the olfactory bulbs and tumour extension into the CNR were analysed together with possible confounding factors including intracranial extension and patient age. RESULTS: There was no significant association between the presence of meningeal hyperintensity or CNR involvement and the occurrence of neurological signs. Although there was a tendency towards shorter survival in dogs with tumour extension into the CNR, multivariable analysis showed no significant difference in survival between dogs with/without CNR involvement, meningeal hyperintensity or intracranial tumour extension (P=0.12, 0.50 and 0.57, respectively). CLINICAL SIGNIFICANCE: In dogs with nasal tumours treated with radiotherapy, tumour extension into the cranium is not necessarily associated with shorter survival in patients without neurological signs at time of diagnosis. Although a definite influence of CNR involvement on case outcome could not be demonstrated, studies with a larger population are warranted.

Postglacial dispersal of Phlebotomus perniciosus into France.

Phlebotomus perniciosus was identified morphologically in samples from France and northeast Spain, and individuals were then characterized at three polymorphic isoenzyme loci (by isoelectrofocusing) and at the mitochondrial DNA locus (by comparative DNA sequence analysis of a fragment of the Cytochrome b gene). The four polymorphic loci gave conflicting patterns of population relationships, which can be explained by hypothesizing different amounts of gene introgression at each locus when two distinctive lineages met in southern France or northeast Spain after isolation in southern Italy and Spain during the Pleistocene Ice Ages. P. perniciosus is an important vector of leishmania infantum and so these population differentiation studies are relevant for predicting the emergence and spread of leishmaniasis in relation to environmental changes, including climate.

Intracranial vascular malformations.

Intracranial vascular malformations are nonneoplastic developmental anomalies that present a variety of clinical patterns, ranging from asymptomatic to fatal intracranial hemorrhage. A practicing radiologist can expect to encounter these abnormalities, which include capillary telangiectasias, venous angiomas (also called developmental venous anomalies), cavernous angiomas, and arteriovenous malformations. The imaging findings that characterize these lesions are reviewed in this article, along with their pathological and clinical features.

The effect of added extra-articular procedure on results of ACL reconstruction.

To determine the efficacy of added extraarticular backup procedure to an intra-articular ligament reconstruction, 70 patients who underwent surgery between July 1988 and May 1991 were reviewed retrospectively. Each patient had undergone either an intra-articular patellar tendon autograft anterior cruciate ligament (ACL) reconstruction alone or with added extra-articular augmentation. Patients were excluded if they had a history of knee problems, if they had ACL surgeries on either knee, or if they became unavailable for followup for an adequate period of time. Thirty-two patients underwent ACL reconstruction with an extra-articular augmentation added (group 1), and 38 patients underwent intra-articular reconstruction alone (group 2). Objective testing consisted of a clinical examination, radiographs, instrumented knee laxity, and subjective evaluation using visual analog scales. There were no statistically significant differences in the clinical or subjective findings between the two groups.

A novel method for liberating viral nucleic acid for assay of water samples with cDNA probes.

Rapid and sensitive methods are needed for the detection of enteric viruses to ensure proper drinking water quality. Gene probes have been shown to be useful for this purpose. Previously, samples to be assayed were treated with a series of phenol-chloroform extractions to release the viral nucleic acid. We have developed a more rapid procedure for liberating or exposing the genome of poliovirus for probing. In this study, a poliovirus model was used to test the ability of heat (65 degrees C for 30 min) for release or exposure of viral nucleic acid. Several different RNase inhibitors were tested for their ability to prevent viral RNA degradation. A comparison of the two methods indicates phenol-chloroform extraction is not necessary before probing. In addition to saving 2-4 h of time, maximum sensitivity levels were consistently obtained using this novel procedure.