Biomedical subjects

C Tölg

Publications and source records attributed to C Tölg.

4 recordsLinked to original sources

PubMed2005

Open vs thorascopic surgical management of bronchogenic cysts.

BACKGROUND: The aim of this study was to compare the operative outcome in children undergoing open vs thoracoscopic resection of bronchogenic cysts. METHODS: The medical records of children who underwent the resection of bronchogenic cysts from 1990 through 2000 were reviewed. Four cyst resections were performed by the open technique and five using a thoracoscopic procedure. The age of the patients, length of hospital stay, duration of drainage, operating time, and outcome were investigated. RESULTS: The mean age of patients undergoing the open procedure was 3 years and 3 months; the mean age for thoracoscopy patients was 7 years and 10 months (p < 0.05). The operating time for the open procedure was 70 +/- 25 min; for the laparoscopic procedure, it was 78 +/- 6 min (p, NS), except in one case with a main bronchial tail that required conversion (320 min). Duration of surgical drainage was 6.5 +/- 3 days for the open procedure and 2.5 +/- 1 days for the thoracoscopic one (p < 0.05). Hospital stay for open patients was 12 days +/- 0 days; it was 6 +/- 1.6 days for thoracoscopic patients (p < 0.01). There were no deaths. The thoracoscopic procedure failed once due to a main bronchial tail and had to be converted to an open procedure. Other early complications included a bronchopulmonary infection after an open cyst excision and an atelectasis after a thoracoscopic cyst excision. Late complications included one reoperation for incomplete excision in each of the two groups. CONCLUSION: Bronchogenic cyst resection can be performed safely. For complete treatment of these patients, total excision of the wall cyst is needed. In selected patients, the thoracoscopic procedure may decrease the duration of surgical drainage and length of hospital stay without increasing the operating time or MSK for complications.

Adolescent↗

PubMed1993

Splicing choice from ten variant exons establishes CD44 variability.

The enormous heterogeneity of the surface protein designated CD44 is in part due to posttranslational modification, and in part due to differential splicing. Alternative splicing occurs within one particular region encoding the extracellular portion of the protein. Comparison of various cDNA clones with different 'inserts' in this variable region with sequences of genomic clones from the mouse has revealed the existence of at least ten exons from which sequences are chosen by alternative splicing. Various combinations of these exons account for the tremendous heterogeneity of CD44 molecules expressed in different tissues, and in progressing tumor cells. The existence of different isoforms of CD44 suggests a broad spectrum of yet unknown physiologic functions.

Amino Acid Sequence↗

PubMed1993

Activated mouse astrocytes and T cells express similar CD44 variants. Role of CD44 in astrocyte/T cell binding.

The CD44 adhesion molecule is expressed by astrocytes, glial-type cells which exhibit features of accessory cells for immune responses in the central nervous system. In primary cultures of mouse astrocytes, we have observed that surface expression and mRNA levels of CD44 are induced following stimulation with either PMA, or tumor necrosis factor alpha plus gamma interferon. Comparison of CD44 splice variants expressed by astrocytes and a T cell hybridoma shows that upon activation, both cell types express a similar pattern of CD44 transcripts. Thus, in both cell types, CD44 transcripts are produced which contain additional exons, including the exon v6 (known to be expressed by in vivo activated lymphocytes and by metastatic variants of tumor cells) as well as variants of larger size. In the autoimmune disease multiple sclerosis, activated T cells cross the blood-brain barrier and lead to inflammation in the central nervous system. Analysis of mice with experimental allergic encephalomyelitis, frequently used as an animal model of multiple sclerosis, shows that CD44 is induced in vivo on glial cells surrounding inflammatory lesions. Using an in vitro model for adhesion between T cells and astrocytes, we have found a correlation between the activation state of these cells and their adhesion potential. Dose-dependent inhibition of adhesion by hyaluronate and by anti-CD44 monoclonal antibody KM81 shows that CD44 is involved in the adhesive interactions between T cells and astrocytes.

Animals↗

PubMed1991

CD44 splice variants confer metastatic behavior in rats: homologous sequences are expressed in human tumor cell lines.

One of several splice variants of CD44 expressed in metastasizing cell lines of rat tumors has been shown to confer metastatic potential to the non-metastatic variant of a rat pancreatic carcinoma line (U. Günthert et al., Cell, 65: 13-24, 1991). The variant-specific rat CD44 sequences were used to detect RNA expression in human cell lines: in carcinoma lines from lung, breast and colon; and in keratinocyte lines. By polymerase chain reaction amplification, complementary DNAs encoding human homologues were isolated and sequenced. The largest splice variant has been found in a large cell lung carcinoma line and in keratinocyte cell lines. It carries at least 5 additional domains (exons) encoding a total of 338 amino acids in the membrane-proximal extracellular region of the standard CD44. Various alternative splice products have been detected in other human tumor cell lines. The distribution of CD44 splice variants is consistent with the speculation that they fulfill functions in only a few restricted differentiation pathways and that in tumor cells these pathways have been reactivated.

Amino Acid Sequence↗