Differences in the expression of glycosaminoglycans in human fibroblasts derived from gingival overgrowths is related to TGF-beta up-regulation.

Glycosaminoglycans (GAGs) play important roles in cell behavior and have the ability to bind and modulate cytokines. Using primary cultured fibroblasts from hereditary gingival fibromatosis (HGF), normal gingiva (NG), and NG treated with cyclosporin-A (NGc) we show changes in the expression and structural characteristics of GAGs as well as in the expression of enzymes involved in their biosynthesis and degradation. In addition, we show the over-expression of TGF-beta1 and TGF-beta type II receptor in HGF and NGc. There is an increase in the GAGs retained in the cellular fraction, and the fine structure of galactosaminoglycans show a decrease in alpha-l-iduronic acid content in HGF and NGc. Elevated extracellular levels of low molecular weight hyaluronan (HA) are found in HGF due to increase in the expression of HA synthase 3 and hyaluronidases 1 and 2. The results bring new insights to the accumulation of extracellular matrix related to TGF-beta over-expression.

Physicochemical and chromatographic evaluation of benzhydrylamine-resin as an anion exchanger solid support.

Benzhydrylamine-resin (BHAR), a copolymer of styrene-divinylbenzene containing phenylmethylamine groups, used as solid support for peptide synthesis, was examined regarding physicochemical and anion exchanger chromatographic properties. The greater the ionic strength of the medium the poorer the solvation of beads. This effect is less pronounced the higher the amino group content of BHAR. The BHAR chromatographic behavior was compared with commercial cationic resins in columns of constant cation binding capacity. Three negatively charged heparan sulfate disaccharides were successfully purified in a 2.4 mmol/g BHAR that showed as good or better anion exchange performance than classical tertiary or quaternary amino group-containing resins. The BHAR chromatographic resin exclusion limit was estimated to be 30 kDa based on purification experiments of heparins of different molecular weight.

Individual effect-site concentrations of propofol at return of consciousness are related to the concentrations at loss of consciousness and age in neurosurgical patients.

STUDY OBJECTIVE: To investigate whether a patient's propofol effect-site concentration at return to consciousness (ROC) was related to the propofol effect-site concentration at loss of consciousness (LOC) and to patients' individual demographic parameters. DESIGN: Prospective study. SETTING: Operating room. PATIENTS: 31 ASA physical status I and II neurosurgical patients with Glasgow Coma Score > 15, and scheduled to receive total intravenous anesthesia with effect-site target controlled infusion (TCI) of propofol and remifentanil. INTERVENTIONS: A constant propofol infusion was administered until LOC. At LOC, remifentanil started with a plasma concentration target of 2.5 ng mL(-1). MAIN RESULTS: Propofol concentration at LOC was 4.9 +/- 1 microg mL(-1). At ROC, propofol and remifentanil concentrations were 1.16 +/- 0.3 microg mL(-1) and 3.41 +/- 1.5 ng mL(-1). Significant correlation was observed between propofol concentrations at ROC and LOC, between propofol concentration at ROC and patient age (48.7 +/- 15 yrs), and between propofol concentrations at ROC and LOC, divided by patient's age. CONCLUSIONS: The correlation between propofol concentrations at ROC and LOC was improved by inclusion of patient age data.

Heparin and heparan sulfate disaccharides bind to the exchanger inhibitor peptide region of Na+/Ca2+ exchanger and reduce the cytosolic calcium of smooth muscle cell lines. Requirement of C4-C5 unsaturation and 1--> 4 glycosidic linkage for activity.

Heparin and heparan sulfate fragments, obtained by bacterial heparinase and heparitinases, bearing an unsaturation at C4-C5 of the uronic acid moiety, are able to produce up to 80% reduction of the cytosolic calcium of smooth muscle cell lines. Unsaturated disaccharides from chondroitin sulfate, dermatan sulfate, and hyaluronic acid are inactive, indicating that, besides the unsaturation of the uronic acid, a vicinal 1 --> 4 glycosidic linkage is needed. An inverse correlation between the molecular weight and activity is observed. Thus, the ED(50) of the N-acetylated disaccharide derived from heparan sulfate (430 Da) is 88 microm compared with 250 microm of the trisulfated disaccharide (650 Da) derived from heparin. Except for enoxaparin (which contains an unsaturation at the non-reducing end and 1 --> 4 glycosidic linkage), other low molecular weight heparins and native heparin are practically inactive in reducing the cytosolic calcium levels. Thapsigargin (sarcoplasmic reticulum Ca(2+)-ATPase inhibitor), vanadate (cytoplasmic membrane Ca(2+)-ATPase inhibitor), and nifedipine and verapamil (Ca(2+) channel antagonists) do not interfere with the effect of the trisulfated disaccharide upon the decrease of the intracellular calcium. A significant decrease of the activity of the trisulfated disaccharide is observed by reducing extracellular sodium, suggesting that the fragments might act upon the Na(+)/Ca(2+) exchanger promoting the extrusion of Ca(2+). This was further substantiated by binding experiments and circular dichroism analysis with the exchanger inhibitor peptide.