Biomedical subjects

Anja Joachim

Publications and source records attributed to Anja Joachim.

5 recordsLinked to original sources

PubMed2005

Effects of excretory/secretory products of Haemonchus contortus on cell vacuolation.

Excretory/secretory (ES) products of the gastric nematode, Haemonchus contortus, have been implicated in the inhibition of gastric acid secretion which follows infection. Parietal cell vacuolation has been observed in abomasal sections from parasitised sheep, and ES prepared in vitro has been reported to cause vacuolation and to increase neutral red (NR) uptake in epithelial cell cultures. We have used the latter approach to examine, at the cellular level, the effects of ES prepared from L3 and adult nematodes. Both NR uptake and cellular vacuolation were increased following exposure to larval or adult ES products. ES preparations from adult worms induced more extensive vacuolation then those from L3 worms and, as with VacA treatment, adherent cells remained viable despite high levels of vacuolation. Whereas VacA-induced vacuolation resulted in NR uptake predominantly localised in vacuoles, this appeared not to be the case with ES-induced vacuolation, suggesting that different mechanisms might be involved. Both ES and VacA exposure was associated with an increased rate of cell detachment.

Abomasum↗

PubMed2004

Scraping or shaking--a comparison of methods for the quantitative determination of Echinococcus multilocularis in fox intestines.

A modified sedimentation technique (the "shaking in a vessel" technique; SVT) to examine intestines for smaller helminths such as Echinococcus multilocularis is described and compared with the intestinal scraping technique (IST). Out of 356 foxes, 26 were E. multilocularis positive, 19 using IST (sensitivity 73.1%) and 25 with SVT (sensitivity 96.2%) after IST. Especially low infection intensities went undetected with IST. The result is comparable to the established sedimentation and counting technique (SCT). SVT is recommended for the routine examination of fox intestines as an alternative to SCT.

Animals↗

PubMed2004

[Is Cryptosporidium a zoonotic agent?].

13 species and several genotypes have been described so far within the genus Cryptosporidium. All of them have very small stages which makes morphological differentiation difficult. The most common species is C. parvum, an enteric pathogen with a broad host spectrum including man and domestic mammals. Molecular biological studies on isolates of C. parvum and other species have shown that the species is likely not to be monophyletic but consists of several species with different host spectra. Based on DNA marker sequences one human and various animal genotypes can be differentiated. Infections of immunocompetent patients with C. parvum are usually associated with the human genotype, while infections of immunodeficient (HIV-positive) patients can also be correlated with various animal genotypes or even primarily animal pathogenic species of Cryptosporidium (e.g., C. felis). According to our current knowledge cryptosporidia are zoonotic agents; however, an animal source of human infections cannot automatically be assumed. Parasites from human patients with low infectivity for cattle and laboratory rodents could be isolated which are not considered as zoonotic.

AIDS-Related Opportunistic Infections↗

PubMed2002

Comparison of fluorescence, antigen and PCR assays to detect Cryptosporidium parvum in fecal specimens.

To optimize routine screening for cryptosporidiosis, 198 stool samples from patients at risk and from calves were examined by enzyme immunoassay (EIA), a direct fluorescent-antibody (DFA) and a modified immunofluorescence assay. Ninety-nine samples were positive in at least one assay, whereas 99 were negative in all three assays. Sensitivity of antigen EIA and DFA were similar (94%, 95% CI: 88-98%, and 91%, 95% CI: 84-95%). The modified immunofluorescence was significantly less sensitive (64%, 95% CI: 55-74%). 149 samples were also examined by two nested PCR assays targeting either the 18S rRNA or Cryptosporidium outer wall protein (COWP) gene. A PCR product was amplified from 86 out of 89 samples being positive in at least one other assay (sensitivity 97%, 95% CI: 91-99%). None was obtained from 60 samples negative in the three other assays. PCR assays did not increase the detection rate. Antigen EIA or DFA appear sufficient for routine Cryptosporidium screening of fecal samples.

Adult↗

PubMedDate not supplied

[Incidence and control of the American giant liver fluke, Fascioloides magna, in a population of wild ungulates in the Danubian wetlands east of Vienna].

Fascioloides magna,the giant liver fluke, is an introduced parasite imported to Europe with infected game which is endemic in the Austrian wetlands of the Danube from Vienna to the Slovakian border. Due to its pathogenicity (especially in roe deer) and its potential of transmission to domestic ruminants a project on the epidemiology and control of this parasite was carried out between 2000 and 2005. To assess distribution faecal droppings from red deer were collected in an area along the Danube and livers of red and roe deer shot or found dead were examined. Simultaneously, triclabendazole-medicated feed was offered repeatedly in several areas of known fluke presence from 2001. The average prevalence of infection as demonstrated by Fascioloides eggs in droppings (n = 145) was 6.3%, with > 50% in some areas. Infection rates decreased from 11.3% (01/2001) to 1.5% (04/2002) in the whole area. In Fischamend, a highly endemic area, prevalences in monthly samples (n = 25) decreased from 70% (01/2001) to less than 1% (01/2005). Similarly, the number of eggs per gram of faeces was significantly reduced. Of 457 red deer livers 15.8% were positive. In the Fischamend area, a reduction of positive livers was also found (2000:100%; 2005:13%), as well as a reduction of the numbers of flukes/liver. Control of F. magna in the Danubian wetlands by anthelmintic treatment proved to be successful although eradication was not achieved.

Animals↗