Periodic muscle weakness and cervical ventroflexion caused by hypokalemia in a Burmese cat

A 2-year-old female Burmese cat was referred to the University Hospital of Companion Animals of Utrecht University because of periodic muscle weakness and cervical ventroflexion. Laboratory examinations revealed hypokalemia. The combination of breed, clinical signs and hypokalemia warranted the diagnosis of 'periodic hypokalemic myopathy', a homozygote recessive hereditary disease in Burmese cats. Potassium supplementation resulted in complete disappearance of the signs. Possible causes of hypokalemia in the cat are discussed.     

Culture-positive tuberculosis in human immunodeficiency virus type 1-infected children

BACKGROUND: Adults infected by HIV have increased susceptibility to Mycobacterium tuberculosis and progress more rapidly to disease. HIV and tuberculosis (TB) coinfection in children has been reported but often lacks bacterial confirmation. We report on the clinical picture, special investigations, clinical course and outcome of 14 children with HIV infection and culture-confirmed TB from a developing country. METHODS: The clinical records of all children, from 1992 to 1997, with HIV infection and culture-proved TB were reviewed. RESULTS: Fourteen (10.4%) of 135 children with vertically transmitted HIV infection, 93% <2 years of age, fit the criteria. Nonresolving pneumonia (4) and otorrhoea (6) were common complaints. A Mantoux test was positive (> or =15 mm) in 6 of 11 children. Extrapulmonary TB was present in 5 cases. Ear swabs were the source of M. tuberculosis culture in 3. Chest radiographs were abnormal in all with hilar and paratracheal lymphadenopathy present in 7. A source case with pulmonary TB was identified for 10. Susceptibility tests were done on 9 strains of which 1 was drug-resistant. Four children were culture-positive 4 to 10 months after initiation of TB treatment. Mortality was 21% and 3 were lost to follow-up. CONCLUSIONS: In HIV-infected children the Mantoux skin test remains useful and culture specimens should be obtained from all sources. Response to treatment is unpredictable, and for this reason repeated cultures should be taken during treatment and a 9-month course of treatment considered.     

PCR amplification of murine immunoglobulin germline V genes: strategies for minimization of recombination artefacts

Murine immunoglobulin germline V genes exist as multiple sequences arranged in tandem in germline DNA. Because members of V gene families are very similar, they can be amplified simultaneously using the polymerase chain reaction (PCR) with a single set of primers designed over regions of sequence similarity. In the present paper, the variables relevant to production of artefacts by recombination between different germline sequences during amplification are investigated. Pfu or Taq DNA polymerases were used to amplify from various DNA template mixtures with varying numbers of amplification cycles. Pfu generated a higher percentage of recombination artefacts than Taq. The number of artefacts and their complexity increased with the number of amplification cycles, becoming a high proportion of the total number of PCR products once the 'plateau phase' of the reaction was reached. Recombination events were located throughout the approximately 1-kb product, with no preferred sites of cross-over. By using the minimally detectable PCR bands (produced by the minimum number of amplification cycles), recombination artefacts can be virtually eliminated from PCR amplifications involving mixtures of very similar sequences. This information is relevant to all studies involving PCR amplification of members of highly homologous multigene families of cellular or viral origin.     

The comparative anatomical study of the parietal region of the skull of the Korean native goat (Capra hircus)

In the skull of the Korean native goat, the parietal region was classified into four types by the degree of the fusion of the bones, the os interparietale, the os parietale and the squama occipitalis of the os occipitale, and the structural variations of these fusions. The fusion appeared first in the sutura interparietoparietalis and that of the sutura sagittalis of both ossa parietalia was followed. There was no fusion between the os parietale and the squama occipitalis of the os occipitale. These results suggest that the os interparietale developed independently but fused to the os parietale after birth, and the os parietale were developed as paired bones in prenatal life and then fused together according to age.