Characterization of aggregating proteoglycans from the proliferative, maturing, hypertrophic, and calcifying zones of the cartilaginous physis

The introduction of a new microanalytical approach has made it possible to investigate the molecular structure and content of proteoglycans within the extracellular matrix of the physis when the volumes of the matrix and the cells change before mineralization of the extracellular matrix. By using extracts of serial frozen sections with a combination of gel chromatography and chemical, radioimmunoassay, and morphometric analyses, we demonstrated that, in the bovine fetal physis, the content of large aggregating proteoglycans reaches a maximum in the extracellular matrix of the hypertrophic zone, in the region where calcification begins, at the time when calcification starts. Morphometric analyses revealed that, at this time, the volume of matrix is reduced to a minimum. There was no evidence that the remaining proteoglycans were reduced in size, nor was aggregation changed at the time when calcification was initiated. Thus, contrary to earlier reports, there is no indication that these molecules need to be degraded and removed for calcification to begin, although a progressive loss of proteoglycans clearly occurs as the volume of the matrix is reduced.(ABSTRACT TRUNCATED AT 250 WORDS)

Intraoperative decision making during thyroid surgery based on the results of preoperative needle biopsy and frozen section

Prognostic factors in well-differentiated thyroid cancer are age of the patient and grade, size, distant metastasis, and extracapsular spread of the disease. However, the surgeon is often not sure about the pathologic diagnosis of thyroid nodules. The accuracy of preoperative studies, such as ultrasonography and thyroid scanning, is limited. The most cost-effective test is fine-needle aspiration, the accuracy of which exceeds 80% in most series. However, a large group of nodules exist for which aspiration cytologic studies are considered to be either suspicious or indeterminate. The decision about the extent of thyroidectomy may be difficult in these patients. Intraoperative frozen section may help the surgeon to distinguish benign from malignant lesions, but as in fine-needle aspiration, the major problem is the distinction between follicular adenoma and follicular carcinoma. The frozen section diagnosis of follicular adenoma was changed to follicular carcinoma in one third of the cases (13 of 38 cases). The decision about the extent of thyroidectomy in patients with follicular adenomas was based on other prognostic factors, such as age and sex of the patient and the size of the nodule. The accuracy of frozen section diagnosis was 95%. Our experience suggests that decisions regarding the extent of thyroidectomy can best be made by preoperative fine-needle aspiration with confirmation by frozen section diagnosis in equivocal cases.

Heparin effect on bone density

In order to provide estimates of the risks of symptomatic osteoporosis and reduced bone density in premenopausal women treated with long-term (greater than 1 month) heparin therapy, we evaluated a cohort of 61 consecutive premenopausal women previously treated with long-term heparin (cases) and a group of controls matched for age, parity and duration between the last pregnancy and evaluation. All patients underwent dual photon absorptiometry of the lumbar spine and single photon absorptiometry of the wrist and most cases underwent plain lateral radiography of the thoracolumbar spine in order to exclude silent fractures. Although none of the cases suffered symptomatic fractures (0 of 61, 95% confidence intervals 0.0 to 5.9%), there was a significantly greater proportion of cases than controls with bone density below our pre-defined levels. The long-term implications of our findings are uncertain but because it is possible that the reduction in bone density predisposes women to fractures, this potential risk should be considered when treating women with long-term heparin.

Needle aspiration biopsy in salivary gland lesions

The value of needle aspiration biopsy in the evaluation and management of salivary gland pathology is controversial. The major reasons for this controversy are the difficulty in cytologic evaluation and the fact that the extent of surgery can be easily defined based on clinical judgement. However, a preoperative diagnosis is helpful in discussions with patients regarding the extent and type of surgery. Apart from the fact that needle biopsy can distinguish benign from malignant conditions, it is also very useful in distinguishing between salivary and other nonsalivary pathology. Over the past 7 1/2 years, we have performed 160 needle aspirations of parotid, submandibular, and submucosal lesions. Adequate specimens for cytologic evaluation were obtained in 155 patients (97%). A total of 84 parotid lesions, 70 submandibular lumps, and 6 submucosal abnormalities were detected. A cytologic diagnosis of benign pathology was made in 120 patients. Twelve patients had lymphoma and the diagnosis was suspected based on needle aspiration. There were 10 patients with tuberculosis and 30 patients with hyperplastic lymph nodes or benign lymphoepithelial disease of the parotid. There were three false-positive and two false-negative reports. No complications such as hematoma, nerve injury, or infection developed. The major difficulty was in distinguishing between malignancy and obstructive sialadenitis in the submandibular region. Needle aspiration was helpful in evaluating lesions in the tail of the parotid and submandibular area. The cytologic distinction between salivary and nonsalivary pathology was useful in planning the appropriate surgery and the extent of surgical resection. From a clinical standpoint, the distinction between benign and malignant salivary and nonsalivary pathology was very helpful. Preoperative diagnosis of Warthin's tumor, lymphoma, or benign lymphoepithelial disease was essential to the correct management of these patients.

Studies of a monoclonal antibody to skeletal keratan sulphate. Importance of antibody valency

A mouse monoclonal antibody (AN9P1) to keratan sulphate is described. In a competitive-inhibition solution-phase radioimmunoassay employing 125I-labelled intact proteoglycan, it reacts preferentially with keratan sulphate bound to the core protein of adult human articular-cartilage proteoglycan and to a much lesser degree with keratan sulphate purified from this proteoglycan. Proteolytic cleavage of the proteoglycan by pepsin and trypsin has little effect on antibody binding, but treatment with papain decreases binding considerably and more than does treatment with keratanase. An even greater decrease in binding is observed after treatment with alkaline borohydride. A comparison of binding of antibody AN9P1 with that of another previously described monoclonal antibody, 1/20/5-D-4, to keratan sulphate [Caterson, Christner & Baker (1983) J. Biol. Chem. 258, 8848-8854] revealed similar binding characteristics, both showing much diminished binding after papain digestion of proteoglycan and even less with purified skeletal keratan sulphate. Removal of the Fc piece of antibody AN9P1 had no significant effect on the differential binding of divalent F(ab')2 fragment to proteoglycan, to papain-digested proteoglycan and to keratan sulphate, although there was a small decrease in binding to papain-digested proteoglycan. Conversion of the antibody into univalent Fab fragment with removal of the Fc piece resulted in diminished binding to proteoglycan, compared with that observed with IgG, and in enhanced binding to free keratan sulphate and to papain-digested proteoglycan. These results suggest that close proximity of keratan sulphate chains on the core protein of proteoglycans favours preferential reactivity of bivalent antibody with these species through cross-bridging of chains by antibody. Conversely, much decreased binding to keratan sulphate on proteoglycan core-protein fragments and to free keratan sulphate results from a lack of close proximity of keratan sulphate. By using univalent Fab fragment in these assays these differences in binding are minimized by preventing cross-bridging and thereby enhancing detection of smaller fragments without sacrificing too much sensitivity of detection of larger proteoglycan species. The persistent preferential binding of Fab fragment to proteoglycan is probably in part the result of the increased epitope density in the intact molecule compared with keratan sulphate in a more disperse form.

Activation of ras oncogene in aflatoxin-induced rat liver carcinogenesis

The presence of activated transforming genes was investigated in four primary aflatoxin-induced rat liver tumors in male Fischer rats, in two cell lines generated from such tumors, in an epithelial liver-derived nontransformed cell line, and in the latter cell line after transformation by aflatoxin B1 in vitro. When DNA extracted from these sources was transfected into NIH 3T3 cells, negative results were obtained from focus assays. Cotransfection of these DNA samples with a gene for resistance to G418, followed by selection for resistance to that antibiotic, and tumorigenicity testing in nude mice demonstrated DNA-mediated transfer of the neoplastic phenotype in all cases except for DNA from the nontransformed cell line. DNA extracted from these primary nude mouse tumors used in a secondary round of transfection with NIH 3T3 cells gave positive results in focus assays, which were conserved through succeeding rounds of transfection. By use of appropriate radiolabeled probes, activated ras oncogenes were detected in all samples. N-ras activation was detected in three of the primary rat liver tumors and both hepatoma cell lines. Ki-ras activation was detected in one primary rat liver tumor, and Ha-ras activation was detected in the cell line transformed in vitro with activated aflatoxin B1. The activated Ki-ras oncogene was further characterized by use of synthetic oligonucleotide probes and was shown to contain a G----A transition at the second nucleotide in codon 12.

The identification and characterization of two populations of aggregating proteoglycans of high buoyant density isolated from post-natal human articular cartilages of different ages

After chromatography on Sepharose CL-2B under associative conditions, high-buoyant-density human articular-cartilage proteoglycans were analysed biochemically and by radioimmunoassay with monoclonal antibodies to a core-protein-related epitope and to keratan sulphate. An examination of proteoglycans from individuals of different ages revealed the presence at 1 year of mainly a single polydisperse population containing chondroitin sulphate (uronic acid) and keratan sulphate. From 4 years onwards a smaller keratan sulphate-rich and chondroitin sulphate-deficient population appears in increasing amounts until 15 years. At the same time the larger population shows a progressive decrease in size from 1 year onward. By 23 years and after the proportion of keratan sulphate in the larger chondroitin sulphate-rich proteoglycan increases. Both adult proteoglycan populations are shown immunologically to aggregate with hyaluronic acid, with the smaller showing a greater degree of interaction. The larger population is richer in serine and glycine, and the smaller population contains more glutamic acid/glutamine, alanine, phenylalanine, lysine and arginine; its protein content is also higher. Whether the larger post-natal population represents a different gene product from the single polydisperse population found in the human fetus, which has a different amino acid composition, remains to be established. The smaller population, which represents approximately one-third the mass of the larger population in the adult, may represent a degradation product of the larger population, in which the hyaluronic acid-binding region and keratan sulphate-rich region are conserved.

Transformation related expression of glutathione-S-transferase P in rat liver cells

A neutral isoenzyme of glutathione transferase designated glutathione-S-transferase 7-7, but also referred to as glutathione-S-transferase P (GST-P) is absent from adult rat liver hepatocytes, but expressed at a very early stage in chemically induced in vivo hepatocarcinogenesis. The expression of this enzyme in a range of aflatoxin B1 (AFB1) associated hepatocarcinogenic systems has been examined, including in vivo induced preneoplastic and neoplastic liver tissue, cell lines derived from hepatomas, primary hepatocytes in culture and an immortalized rat liver cell line before and after transformation in vitro either by transfection with ras oncogenes or by treatment with metabolically activated AFB1. Analyses of total cytosol proteins using a polyclonal antibody to GST-P did not detect the presence of GST-P protein in cytosols from control or regenerating liver. A low level of expression was detected in the immortalized, non-transformed epithelial cell line, but a greatly induced level occurred subsequent to transformation of these cells by either of the two techniques used. High levels of the protein were detected in in vivo induced preneoplastic and neoplastic tissues, and in the cell lines derived from them. Total RNA fractions isolated from the various cells or tissues, when examined with a cDNA probe for GST-P mRNA, showed it to be absent from control and regenerating rat liver. It was present at low levels in the untransformed cell line and primary hepatocytes after 48 h in culture, but present at greatest abundance in the in vivo and in vitro transformed cells. The results indicate that the highest elevation in expression of this protein is associated with the stage of definitive malignant transformation in in vitro carcinogenesis, and this could have relevance in defining comparable events in the in vivo multistage sequence.

Immunodetection and characterization of the degradation of cartilage proteoglycans in vitro and in vivo

The large aggregating cartilage proteoglycans can be detected immunologically using antibodies directed against the hyaluronic acid-binding region, core protein, keratan sulfate, chondroitin sulfate, and hyaluronic acid. With radioimmunoassays we have detected proteoglycans released from adult human articular cartilage in vitro and in vivo. In vitro cleavage appears to occur mainly adjacent to the hyaluronic acid binding region with the release of the rest of the molecule. Two distinct populations have been observed, the larger of which is chondroitin sulfate-rich and the smaller keratan sulfate-rich. Although they are a little smaller and probably aggregate less with hyaluronic acid, these populations correspond in size and composition to two similar populations detected in situ in healthy adult human articular cartilage. In vivo studies of synovial fluid have revealed that the proteoglycan fragments are smaller and the most commonly detected fragment is the hyaluronic acid binding region. This suggests that in vivo further degradation occurs, probably due to degradation mediated by the inflamed synovium and polymorphonuclear leucocytes present in the synovial fluid of inflamed joints.

The immunologic detection and characterization of cartilage proteoglycan degradation products in synovial fluids of patients with arthritis

Antibodies were used in radioimmunoassays with gel chromatography to detect the hyaluronic acid-binding region, core protein, and keratan sulfate of human cartilage proteoglycan in the synovial fluids of patients with rheumatoid arthritis, juvenile rheumatoid arthritis, and osteoarthritis. All fluids contained proteoglycan that was mainly included on Sepharose CL-4B; this result indicates cleavage of proteoglycan (which is normally excluded). The hyaluronic acid-binding region was the smallest and most commonly detected fragment. It was relatively free of keratan sulfate and core protein, and it could sometimes bind to hyaluronic acid. Other larger fragments containing core protein and/or keratan sulfate were detected in every fluid.

Fine-needle aspiration in the diagnosis of cervical lymphadenopathy

The extent of workup in patients with cervical adenopathy has always been controversial. Extensive workup in the absence of a histologic diagnosis indicative of a malignant process is unwarranted. Although open biopsy may be necessary for certain benign conditions, its routine application for metastatic nodes is not advised. We have used fine-needle aspiration as a routine procedure in the initial evaluation of cervical adenopathy. Over the past 3 years, 140 needle aspirations have been performed. Adequate specimens were obtained in 97 percent of the patients and the diagnostic accuracy was 96 percent. Overall, 45 percent of the patients had the diagnosis of a malignant tumor established whereas others had benign tumors. Metastatic squamous cell carcinoma was diagnosed accurately in all of the patients. Other malignant tumors reported accurately included lymphoma, adenocarcinoma, and metastatic thyroid carcinoma. Among the benign conditions, accurate diagnoses could be established in patients with tuberculosis, chronic lymphadenitis, and hyperplastic lymph nodes. The findings of fine-needle aspiration are helpful in directing subsequent workup. If the findings do not correlate with the clinical suspicion, greater weight is given to the clinical picture and diagnostic workup appropriate for the suspected disease is performed. Proper use of fine-needle aspiration requires close communication between an experienced cytologist and the head and neck surgeon. This series demonstrates that fine-needle aspiration is a safe, accurate, and valuable tool for the evaluation of cervical adenopathy.

Localization of a dermatan sulfate proteoglycan (DS-PGII) in cartilage and the presence of an immunologically related species in other tissues

A monoclonal antibody to a core-protein-related epitope of a small dermatan sulfate-rich proteoglycan (DS-PGII) isolated from adult bovine articular cartilage (22) was used to localize this molecule, or molecules containing this epitope, in bovine articular cartilages, in cartilage growth plate, and in other connective tissues. Using an indirect method employing peroxidase-labeled pig anti-mouse immunoglobulin G, DS-PGII was shown to be present mainly in the superficial zone of adult articular condylar cartilage of the metacarpal-phalangeal joint. In fetal articular and epiphyseal cartilages, the molecule was uniformly distributed throughout the matrix. By approximately 10 months of age it was confined mainly to the superficial and middle zones of articular cartilage and the inter-territorial and pericellular matrix of the deep zone. DS-PGII was not detected in the primary growth plate of the fetus except in the proliferative zone, where it was sometimes present in trace amounts. In contrast, it was present throughout the adjacent matrix of developing epiphyseal cartilage. In the trabeculae of the metaphysis, strong staining for DS-PGII was seen in decalcified osteoid and bone immediately adjacent to osteoblasts. Staining was also observed on collagen fibrils in skin, tendon, and ligament and in the adventitia of the aorta and of smaller arterial vessels in the skin. These observations indicate that DS-PGII and/or molecules containing this epitope are widely distributed in collagenous tissues, where the molecule is intimately associated with collagen fibrils; in adult cartilage this association is limited mainly to the narrow parallel arrays of fibrils which are found in the superficial zone at the articular surface. From its intimate association and other studies, this molecule may play an important role in determining the sizes and tensile properties of collagen fibrils; it may also be involved in the calcification of osteoid but not of cartilage.

Isolation of dermatan sulfate proteoglycans from mature bovine articular cartilages

Two species of dermatan sulfate proteoglycans, called DS-PGI and DS-PGII, have been isolated from mature bovine articular cartilages. On sodium dodecyl sulfate-polyacrylamide gel electrophoresis at low ionic strength in 0.01 M phosphate the dermatan sulfate proteoglycans appeared as a single polydisperse species whose molecular weight ranged from 80,000 to 140,000. The dermatan sulfate proteoglycans eluted as a single peak on Sepharose CL-4B chromatography in 4 M guanidine hydrochloride and showed no tendency to separate into two components. Following chondroitinase AC and ABC digestion, a core protein was obtained whose molecular weight was 45,000. However, what appeared to be a single dermatan sulfate proteoglycan was consistently separated into two species of distinctly different mobilities by sodium dodecyl sulfate-polyacrylamide gel electrophoresis at high ionic strength in 0.375 M Tris. The molecular weight of the smaller species (DS-PGII) ranged from 87,000 to 120,000. The molecular weight of the larger species (DS-PGI) ranged from 165,000 to 285,000. DS-PGI self-associates in 0.375 M Tris, while DS-PGII does not. This phenomenon was exploited to separate DS-PGI and DS-PGII by preparative electrophoresis on 5 to 20% gradient slab gels. The immunological identities of the individual species, DS-PGI and DS-PGII, were examined by enzyme-linked immunosorbent assay using polyclonal antiserum to cartilage-specific proteoglycan monomer from bovine articular cartilage and polyclonal and monoclonal antibodies to DS-PGII. The polyclonal antiserum to cartilage-specific proteoglycan monomer did not react with DS-PGI or DS-PGII, indicating that DS-PGI and DS-PGII possess different core proteins from cartilage-specific proteoglycan monomer. Polyclonal and monoclonal antibodies raised against the mixture of DS-PGI and DS-PGII reacted strongly with DS-PGII, but weakly or not at all with DS-PGI. These results suggest that DS-PGI and DS-PGII possess different core proteins and may represent two different species of dermatan sulfate proteoglycans.

Can a calcaneal morphologic index determine the degree of osteoporosis?

The proposal that a scoring system of the radiographic trabecular patterns of the os calcis could be related to degree of osteoporosis was tested. The technique fails as it showed no correlation with actual bone density determined by a Compton scatter technique and because of a low level of observer concordance. Possible reasons for the poor performance of the index developed in India when applied to North Americans are discussed.

[Endocarditis parietalis fibroplastica Löffler]

Report on an endocarditis parietalis fibroplastica Löffler in a 54-year-old male. Discussion of the localisation, pathologico-morphologic findings as well as of the differential diagnosis and the therapy. Particular reference to the ten-year course of the disease, which possibly is the success of the treatment.

A prospective random study of a single agent versus combination antibiotics as therapy in penetrating injuries of the abdomen

One hundred patients undergoing operation for penetrating and potentially contaminated wounds of the abdomen were given cefamandole or a combination of cephalothin-tobramycin by a random, single blind method as preventive therapy. Results were evaluable for 49 patients receiving cefamandole for a success rate of 93.9 per cent. The 45 evaluable results in the second group had a success rate of 88.9 per cent. Those in the single therapy group also required fewer days of treatment and of hospital confinement, resulting in lower per patient cost. Results of this study show cefamandole to be an efficacious alternative for surgeons seeking a single agent therapy.

An Automated Technic for the Assessment of Thyroid Status, Based upon the Binding of I131-Triiodothyronine by Serum

An automated technic is described for the direct assessment of I131-triiodothyronine binding by serum. The adsorbants used in the manual technics are replaced by dialysis. The radioactivity in the dialysate is measured in a continuous-flow scintillation system. Results obtained from 71 patients of varying thyroid status compare favorably with those of a standard manual I131-triiodothyronine resin uptake test.