Biomedical subjects

E Engelke

Publications and source records attributed to E Engelke.

4 recordsLinked to original sources

PubMed2006

Ethambutol resistance testing by mutation detection.

OBJECTIVE: To identify chromosomal mutations that confer resistance to ethambutol (EMB) in Mycobacterium tuberculosis. DESIGN: Drug-resistant (n = 235) and drug-susceptible (n = 117) M. tuberculosis isolates collected from the Western Cape in South Africa were subjected to embB gene analysis and the results were compared to phenotypic EMB testing. RESULTS: Genotypic analysis identified mutations at codon 306 of the embB gene in 20% (47/235) of the resistant isolates in comparison to only 1.7% (4/235) of those that were phenotypically resistant to EMB by the agar diffusion method. No gene mutations were detected in susceptible isolates. Phenotypic retesting in BACTEC demonstrated that the 47 genotypically resistant isolates were phenotypically resistant to EMB. This implies that 91.4% (43/47) of EMB resistance had been phenotypically missed by routine laboratory procedures. EMB resistance was closely linked to multidrug resistance (MDR); 87.2% (41/47) of the EMB-resistant isolates were resistant to both isoniazid and rifampicin. A newly developed one-step amplification refractory mutation system polymerase chain reaction (ARMS-PCR) method correctly detected the EMB-resistant genotype. CONCLUSION: Implementation of more accurate diagnosis of EMB resistance may enhance patient management in South Africa, as standardised treatment of MDR-TB with second-line drugs is currently dependent on the outcome of the EMB resistance test.

Antitubercular Agents↗

PubMed2006

Differentiation of Mycobacterium tuberculosis complex by PCR amplification of genomic regions of difference.

Differentiation of members of the Mycobacterium tuberculosis complex by conventional mycobacteriological methods is time consuming, making surveillance of species-specific disease difficult. A two-step, multiplex polymerase chain reaction (PCR) method based on genomic regions of difference (RD1, RD1(mic), RD2(seal), RD4, RD9 and RD12) was developed for the differentiation of M. canettii, M. tuberculosis, M. africanum, M. microti, M. pinnipedii, M. caprae, M. bovis and M. bovis BCG. The size of the respective multiplex PCR amplification products corresponded to the presence of the different M. tuberculosis complex members. This method allows for rapid differentiation, making it suitable for routine laboratories and surveillance purposes.

Electrophoresis, Polyacrylamide Gel↗

PubMed1999

The course of blood vessels in the hip joint capsule of the dog.

The course and the arrangement of capsular blood vessels in the joint capsule's wall, together with their extracapsular origins, were investigated using cleared specimens that had been injected with Latex, or Technovit, or India-ink in serum. Arteries enter areas of the joint capsule's wall near its femoral as well as coxal attachment. The intramural vascular network is arranged in layers which are assigned to the stratum fibrosum and stratum synoviale, with one or two intermediate, less distinct layers in between. The ramification in the network of the stratum fibrosum is mainly stellate. Circular anastomoses connecting the supplied areas are located in the capsule's periphery. In the stratum synoviale, the vascular network is made of close, elongated meshes in a circular extension.

Animals↗

PubMed1996

Methodology of comparing three milking clusters in a large dairy herd.

Data for milking parameters were obtained from three different milking clusters using a modified Latin square design to take into account the real milking time regimen of the farm and the time requirements to sort cows. In this modification, cows entered the milking parlor in a random sequence rather than by group. In addition, the clusters were assigned to milking sites. Parameters were compared for 554 cows from one dairy herd that was divided into two smaller herds of 410 and 144 cows. A modified Latin square design was used to compare clusters. The results revealed that 92.1 and 95.5% of cows in Experiments 1 and 2, respectively, were treated by all three clusters; 7.9 and 4.5% of the cows, respectively, were treated by only two clusters; and no cow was treated by only one cluster. The milking parameters for both experiments were in good agreement. Results demonstrated that the modified Latin square design was equivalent to the original Latin square design under the constraint that the number of cows included in one experiment should be > 100 and that the number of milkings should not be < 200 per cluster.

Animals↗