A persisting secular trend for body measurements in Dutch children. The Oosterwolde 11 study

To investigate whether the secular trend for growth in Dutch children still exists, the Oosterwolde I study of 1980 was repeated in 1989. A persisting secular trend was visible for height while the z scores of body proportions show no change during the past 10 years, which suggests that there is no change in the timing of puberty.     

Low molecular weight heparin and prevention of postoperative thrombosis in abdominal surgery.

In a prospective, double-blind, randomized multicenter trial the efficacy and safety of low molecular weight heparin and unfractionated heparin were compared for the prevention of postoperative deep vein thrombosis in patients undergoing abdominal surgery. Six hundred and seventy-three patients were randomly allocated to the two prophylaxis groups; 20 of these, however, did not undergo surgery and did not receive any prophylaxis. Of the remaining 653 patients 323 received one subcutaneous injection of 3,000 anti-Xa units of low molecular weight heparin and 330 received subcutaneously 5,000 U heparin three times a day. Treatment was initiated 2 h preoperatively and continued for 7 to 10 days. The occurrence of DVT was determined by the 125I-labelled fibrinogen uptake test and phlebography. Venous thrombosis was diagnosed in 24 of 323 patients (7.4%) treated with low molecular weight heparin and in 26 of 330 patients (7.9%) treated with low-dose heparin. DVT of proximal veins was detected in four patients of the low molecular weight heparin group and in three patients of the low-dose heparin group. During the observation period three pulmonary emboli - one fatal and two non-fatal - occurred in patients receiving prophylaxis with low-dose heparin. No pulmonary embolism was found in patients treated with low molecular weight heparin. Both prophylactic schemes were well tolerated. Intra- and postoperative blood loss, incidence of wound hematoma, frequency and volume of intra- and postoperative blood transfusion were similar in both groups with a slight advantage for the low molecular weight heparin group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Synovial extracellular matrix II. Specific incorporation of immunoglobulin into the cell-free matrix of pannus.

To determine whether immune complex-like material is incorporated into the extracellular matrix (ECM) of proliferated RA synovium, cell-free matrices were isolated from pannus removed at joint replacement surgery, and were subjected to differential extraction. When the IgG and albumin concentrations in the ECM extracts were compared to those in simultaneously obtained synovial fluids, the IgG was found to be enriched 8.8-fold. Approximately 95% of the IgG was extractable with 6M Guanidine-HCl and 8 M Urea-B-ME. Further extraction with collagenase and low-pH buffers did not result in any additional recovery of IgG. Matrix-associated IgG demonstrated a restricted mobility on IEF with a pI of 4.8. The extracellular matrix of RA pannus is enriched in an acidic IgG species. Incorporation of IgG appears to be secondary to non-covalent interactions and may represent an additional reservoir of immune complex material in the rheumatoid joint.     

Release of parathyroid hormonelike peptides by fetal rat long bones in culture

We observed that culture medium conditioned with fetal rat long bones stimulated cyclic AMP production by canine renal cortical membranes. This cyclase-stimulating activity (CSA) was retained by an ultrafiltration membrane with a molecular weight cutoff of 5000; three biologically active peaks with an approximate molecular weight of 18,000-25,000, 9000-12,000, and 4000-6000 were separated by high-performance liquid chromatography. The biologic activity was destroyed by trypsin digestion. The stimulation of adenylate cyclase by the medium and by the three peaks was inhibited by [N-leu8,18,Tyr34]parathyroid hormone-(3-34)-amide and by [Tyr34]parathyroid hormone-(7-34)amide. Preincubation of the bone culture medium and of the three peaks with an antibody raised against human parathyroid hormone-(1-34) did not decrease the biologic activity more than incubation with nonimmune serum. However, the biologic activity of the three active peaks was significantly suppressed after preincubation with an antiserum directed against the N-terminal region of the parathyroid hormone-related peptide of malignancy. The release of CSA into the bone culture medium was enhanced by parathyroid hormone induction and by 1,25-dihydroxycholecalciferol. It was decreased by calcitonin. We conclude that fetal murine bones in culture release peptides that stimulate the adenylate cyclase of renal cortical membranes. These peptides are antigenically similar to the parathyroid hormone-related peptide of malignancy. Their release from bones is modulated by hormones that control bone resorption.     

Growth of Hodgkin cell lines in severely combined immunodeficient mice.

No animal model exists for the in vivo growth of Hodgkin's-lymphoma-derived cells. Neither unmanipulated Hodgkin's-disease(HD)-derived cell lines nor primary biopsy tissue could be grown in nude mice. Since the severe combined immunodeficient (SCID) mouse has been reported to be a better recipient for transplanted human lymphatic tissue than the nude mouse, we tested whether SCID mice provide suitable conditions for the in vivo growth of HD cell lines. Tumorigenicity of HD cells was tested in untreated and pre-treated SCID mice and in another combined immunodeficient mouse strain, beige/nude/X-linked immunodeficient (BNX) mouse. SCID mice supported in vivo growth of the 6 HD cell lines tested (L428, L540, L591, DEV, HD-LM2, KM-H2). Only one of the 6 lines (DEV) was tumorigenic in BNX mice. No HD cell line proliferated in T-cell-deficient nude mice. Thus, in vivo growth of HD cell lines appeared to be related to the degree of host immunodeficiency. Additional growth supportive treatments such as fibrosarcoma co-transplantation, intraperitoneal mineral oil injection or immunosuppressive pre-treatment (anti-asialo-GMI-antibody injection) permitted growth of 3 additional HD cell lines in BNX mice. The immunophenotype and karyotype of explanted graft cells were identical to the original cell lines. Our experiments describe an effective and reproducible xenograft model for growth of Hodgkin's-disease-derived cell lines. This may be of value for elucidating the growth characteristics of Hodgkin's-lymphoma-derived cells as well as for testing new therapeutic regimens.     

Biostability and blood-contacting properties of sulfonate grafted polyurethane and Biomer.

Sulfonate-containing polyurethanes were evaluated for in vivo biodegradation using subcutaneously implanted tensile bars. In addition, these anionically charged polyurethanes were evaluated for in vivo activation of human complement C3a and ex vivo platelet deposition in arteriovenously-shunted canines. The sulfonate derivatized polymers included laboratory synthesized polyurethane and Biomer. Other polymers used for references included Intramedic polyethylene, Silastic and a poly(ethylene oxide) based polyurethane. The biodegradation results indicated that Biomer and the laboratory sulfonated Biomer (both manufactured with stabilizers), remained mechanically stable, retaining both tensile strength and elasticity after 4 weeks of subcutaneous implantation. The unstabilized polyurethanes (with or without sulfonation), however, showed marked cracking and a loss of mechanical properties after the same period of subcutaneous implantation. Sulfonated polyurethanes depressed human complement C3a activation in plasma, as indicated by decreased levels of anaphylatoxin production. The results of canine ex vivo blood contacting experiments were conducted in both an acute and chronic model and demonstrated decreased platelet deposition and activation for the sulfonated polyurethanes.     

Early complications of stenting in patients with congenital heart disease: a multicentre study.

AIMS: Stenting has become an established interventional cardiology procedure for congenital heart disease. Although most stent procedures are completed successfully, complications may occur. This multicentre study evaluated early complications after stenting in patients with congenital heart disease, including potential risk factors. METHODS AND RESULTS: In this combined Dutch-Belgian retrospective study, 309 consecutive patients had undergone 366 catheterizations and received 464 stents in 13 different anatomical positions (418 sites). Seventy-two stenting-related complications (19%) occurred, of which 24 (5.7%) were major. Seven procedure-related deaths were documented (2.3%). Stent malpositioning and embolization were most common (7.7%). The use of non-premounted stents tended to be associated with higher complication rates. Centre inexperience with stenting and stenting of native vs. post-surgical stenosis tended to be associated with increased major complication rates. CONCLUSION: After stenting, complications are common for congenital heart disease. The vast diversity of stenotic sites combined with relatively small patient populations makes these procedures sensitive to complications. Combining operator experience may reduce the risks of stenting in congenital heart disease. The availability of premounted stents for greater vessel diameters will likely reduce incidences of stent migration and embolization.