Biomedical subjects

Ewa Johansson

Publications and source records attributed to Ewa Johansson.

4 recordsLinked to original sources

PubMed2003

Tonsillectomy--clinical consequences twenty years after surgery?

Tonsillectomy (T) is one of the most common surgical procedures performed on children. Long-term follow-up studies concerning its consequences are lacking. This study is the first study done on a group of patients that underwent T in their childhood, about 20 years ago. The investigation is a cohort study, which followed-up 18 patients who were tonsillectomized 20 years ago. It was to be determined whether these subjects suffer from more respiratory tract infections (or other infections) today, than people who are not tonsillectomized. A group of 54 age-matched subjects were selected for comparison. A questionnaire was mailed to the study population. No significant differences were found between the groups in the frequency of upper respiratory tract infection (URI). The mean number of URI's was approximately [MSOffice1]2.5 per year in both groups. The duration of the URI's was identical in each group. A high temperature was present to the same extent in each group. Absence from work, number of visits to physicians and the use of antibiotics were the same in each group. However, the prevalence of chronic disease was greater in the T-group than in the comparison group. The difference was significant with a Relative Risk of 9.41 and a Confidence Interval differing from 1 (1.13<RR<78.14) for the T-population to develop chronic disease. Because of the small number of the present study population, the results must be validated by further immunological and epidemiological studies on long-term effects of tonsillectomy.

Adult↗

PubMed2003

Cholera toxin protects against action by Clostridium difficile toxin A. The role of antisecretory factor in intestinal secretion and inflammation in rat.

UNLABELLED: The protein antisecretory factor (AF) inhibits intestinal fluid secretion induced by the cholera toxin (CT) and Clostridium difficile toxin A (CDA). The present work investigated whether CT-induced AF protects against the enterotoxin action by CDA. Rats were pretreated perorally with CT or buffer as control, whereafter CDA-induced fluid secretion and cytotoxicity was tested in vivo in ligated intestinal loops; the mucosal level of AF was estimated using the Western blot technique. Rats given repeated peroral doses of CT became tolerant to CDA, the inhibition of fluid secretion and of cytotoxicity being 79% in eight out of nine animals. The repeated CT-treatment also induced long-lasting rise of AF in the mucosal epithelium. Recombinant AF given either perorally or intravenously inhibited both fluid secretion and cytotoxicity by CDA; similar results were obtained with a truncated 16-mer AF peptide. IN CONCLUSION: peroral CT-treatment induced tolerance to CDA in rat small intestine. The tolerance was probably mediated by AF induced via action of cholera toxin on the enteric nervous and immune system.

Animals↗

PubMed2003

Food-induced antisecretory factor activity is correlated with small bowel length in patients with intestinal resections.

Specially processed cereals (SPC) can increase antisecretory factor (AF) activity in humans with an intact intestine. The aim of the present study was to investigate whether AF synthesis could be induced in patients who had been subjected to intestinal resections. Eight patients with varying extents of intestinal resections due to Crohn's disease and six healthy controls participated. All subjects received 54 g SPC daily for 2 weeks. Plasma AF activity was determined before, during and after the treatment period. Baseline diet and medications were kept unchanged. The patients registered the daily number of bowel movements. The SPC diet increased AF activity in all controls. In the patients there was a significant correlation between the length of the remaining small intestine and AF induction (r=0.94, p<0.01) and only those patients with a remaining small intestine of about 3 m reached AF values comparable to those in healthy subjects. It is concluded that small bowel length is related to the ability of humans to induce AF activity by dietary means.

Adult↗

PubMedDate not supplied

Immunohistochemical staining patterns using epitope-specific antibodies indicate conformation variants of antisecretory factor/S5a in the CNS.

Antisecretory factor (AF/S5a/Rpn10) was originally identified through its ability to counteract pathological secretion. AF is also a potent anti-inflammatory agent, a neuromodulator, and an important component of the proteasome. Human AF has a calculated molecular mass of 41 kDa and a pI of 4.7. No family of AF-like proteins has been identified. AF has multiple functions in the cell, and different functional forms could exist as a result of post-translational modifications. Epitope-specific antibodies covering the entire length of AF were used to investigate whether modified forms of AF could be detected in the porcine spinal cord by Western blots, 2D gels, and immunohistochemistry (IHC). Western blot and 2D gels showed that all antisera detected a single protein with very similar molecular mass and pI. However, IHC resulted in an epitope-specific subcellular staining pattern. Antisera recognizing epitopes in the N-terminal part of AF, containing the antisecretory activity, showed a more restricted localisation than antisera directed at the C-terminal part, containing the ubiquitin-binding sites. We suggest that AF can exist in several conformational variants, perhaps due to differences in redox state and/or pH in the various cellular compartments. Such conformational changes could be of functional importance.

Amino Acid Sequence↗