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.     

Evaluation of stem cell reserve using serial bone marrow transplantation and competitive repopulation in a murine model of chronic hemolytic anemia

Serial transplantation and competitive repopulation were used to evaluate any loss of self-replicative capacity of bone marrow stem cells in a mouse model with increased and persistent hemopoietic demands. Congenic marrows from old control and from young and old mice with hereditary spherocytic anemia (sphha/sphha) were serially transplanted at 35-day intervals into normal irradiated recipients. Old anemic marrow failed or reverted to recipient karyotype at a mean of 3.5 transplants, and young anemic marrow reverted at a mean of 4.0 transplants, whereas controls did so at a mean of 5.0 transplants. In a competitive assay in which a mixture of anemic and control marrow was transplanted, the anemic marrow persisted to 10 months following transplantation; anemic marrow repopulation was greater if anemic marrow sex matched with the host. It is possible that lifelong stress of severe anemia decreases stem cell reserve in the anemic sphha/sphha mouse marrow. However, marginal differences in serial transplantation number and the maintenance of anemic marrow in a competition assay would suggest that marrow stem cells, under prolonged stress, are capable of exhibiting good repopulating and self-replicating abilities.     

The traumatic dural sinus injury — a clinical study

Summary In a period of 13 years 978 cases of severe head injuries were operated on in our clinic. An analysis of the medical reports includes injuries of the superficial dural sinus (39 cases=4%): among these injuries of the anterior and central part of the superior sagittal sinus (66 per cent), injuries of the transverse sinus (18 per cent), injuries of the posterior part of the superior sagittal sinus (8 per cent), and combined injuries of different dural sinuses (8 per cent).Clinical data, i.e. the causes of accident, radiological examination results, intracranial lesions, operation technqiues and outcome are analysed and discussed. The analysis of cases with dural sinus injuries shows a high mortality rate (total mortality rate: 16 patients=41%; intra-operative mortality rate: 8 patients=20%).     

Relationship between monitoring parameters and perinatal outcome in severe, early intrauterine growth restriction.

OBJECTIVE: To investigate whether pathological changes in the umbilical artery (UA), ductus venosus (DV) and short-term fetal heart variation are related to perinatal outcome in severe, early intrauterine growth restriction (IUGR). METHODS: This multicenter, prospective, longitudinal, observational study was carried out in the Departments of Fetal Medicine and Obstetrics in Hamburg, Amsterdam, Utrecht and London. In 70 singleton pregnancies with IUGR fetuses, delivered at 26-33 weeks of gestation because of antepartum fetal distress, short-term variation (STV) of fetal heart rate, pulsatility index of the fetal UA (UA PI) and DV pulsatility index for veins (DV PIV) were assessed at least weekly. The final measurement was performed within 24 h of delivery. Standard cut-off levels (2 SD or 3 SD, absent flow or reversed flow) were used and new cut-off levels were calculated by means of receiver-operating characteristics analysis. Adverse outcome was defined as perinatal death, cerebral hemorrhage (> or = Grade II) or bronchopulmonary dysplasia before discharge. The predictive value for adverse outcome was calculated for different cut-off levels of the monitoring parameters, adjusted for gestational age (GA), by multivariate logistic regression analysis. Data were analyzed separately for three different time blocks, namely 8-14, 2-7 and 0-1 days before delivery. RESULTS: Adverse perinatal outcome occurred in 18/70 (26%) infants. During the last 24 h before delivery DV PIV and UA PI were significantly higher and STV lower in the adverse outcome group, while 2-7 days before delivery only DV PIV was significantly higher. Adverse perinatal outcome could be predicted at 0-1 days before delivery by DV PIV at a cut-off of three multiples of the SD (odds ratio (OR) 11.3; 95% CI 2.3-57) and GA (OR 0.4; 95% CI 0.3-0.8), at 2-7 days by DV PIV at 2 SD (OR 3.0; 95% CI 0.8-12) and GA (OR 0.5; 95% CI 0.3-0.8) and at 8-14 days by DV PIV at 2 SD (OR 3.9; 95% CI 0.8-20) and GA (OR 0.5; 95% CI 0.3-0.8). Other parameters did not contribute to the multivariate model. CONCLUSIONS: DV PIV measurement is the best predictor of perinatal outcome. This measurement may be useful in timing the delivery of early IUGR fetuses and in improving perinatal outcome, even when delivery may be indicated at an earlier GA. However, as GA was also an important factor influencing outcome, with poorer outcome at earlier gestation at delivery, this hypothesis needs to be tested in a multicenter, prospective, randomized trial.     

Use of digital photography in the Case orthodontic clinic.

In 2002, the orthodontic clinic at Case Western Reserve University totally converted to digital photography. We want to share the learning curve during this transition with clinicians planning the same change. A system and a protocol were developed for this transition; they have been in use for over a year. This system allows the handling of digital cameras when there are more clinicians than cameras; it can be applied to various specialties or fields.