Testing a theoretical model of imminent fracture risk in elderly women: an observational cohort analysis of the Canadian Multicentre Osteoporosis Study.

We examined the underlying relationship between fracture risk factors and their imminent risk. Results suggested that having past year fracture, worse past year general health, worse past year physical functioning, and lower past year BMD T-score directly predicted higher imminent fracture risk. Past year falls indirectly predicted imminent risk through physical functioning and general health. INTRODUCTION: This study aimed to examine direct and indirect effects of several factors on imminent (1 year) fracture risk. METHODS: Data from women age 65 and older from population-based Canadian Multicentre Osteoporosis Study were used. Predictors were identified from study years 5 and 10, and imminent fracture data (1-year fracture) came from years 6 and 11 (year 5 predicts year 6, year 10 predicts year 11). A structural equation model (SEM) was used to test the theoretical construct. General health and physical functioning were measured as latent variables using items from the 36-Item Short Form Health Survey (SF-36) and bone mineral density (BMD) T-score was a latent variable based on observed site-specific BMD data (spine L1-L4, femoral neck, total hip). Observed variables were fractures and falls. Model fit was evaluated using root mean square error of approximation (RMSEA), Tucker Lewis index (TLI), and comparative fit index (CFI). RESULTS: The analysis included 3298 women. Model fit tests showed that the SEM fit the data well; χ2(172) = 1122.10 < .001, RMSEA = .03, TLI = .99, CFI = .99. Results suggested that having past year fracture, worse past year general health, worse past year physical functioning, and lower past year BMD T-score directly predicted higher risk of fracture in the subsequent year (p < .001). Past year falls had a statistically significant but indirect effect on imminent fracture risk through physical functioning and general health (p < .001). CONCLUSIONS: We found several direct and indirect pathways that predicted imminent fracture risk in elderly women. Future studies should extend this work by developing risk scoring methods and defining imminent risk thresholds.

The effect of glucosamine on glucose metabolism in humans: a systematic review of the literature.

OBJECTIVE: Glucosamine is commonly used for the treatment of osteoarthritis. It is available as an over the counter preparation and also as a prescription pharmaceutical. There is concern from animal experiments that glucosamine may alter glucose metabolism through the hexosamine biosynthetic pathway. The objective of this systematic review is to determine if exogenous glucosamine adversely affects glucose metabolism in humans. This review does not separate out the effects on glucose metabolism of the various glucosamine preparations. METHOD: An English-language literature search of MEDLINE, EMBASE and EBM Reviews (1950-February 2009) was conducted. The bibliographies of selected papers were manually searched for additional references. Two reviewers independently analyzed studies for quality and content using a standardized data extraction form. RESULTS: Eleven studies were included. Six studies were randomized controlled trials and the remaining five were prospective studies with or without controls. Four of the studies found decreased insulin sensitivity or increased fasting glucose in subjects taking glucosamine. Three of these were clinical studies using oral glucosamine. Studies that included subjects with baseline impaired glucose tolerance or insulin resistance were more likely to detect an effect on glucose metabolism than studies without such subjects. CONCLUSION: Clinical studies, including three using oral glucosamine, have provided mixed evidence about the effect of exogenous glucosamine on glucose metabolism in humans. Therefore, more studies are needed, particularly including subjects at high risk for impairments in glucose homeostasis, before a definite conclusion can be made.

Modulation of articular chondrocyte proliferation and anionic glycoconjugate synthesis by glucosamine (GlcN), N-acetyl GlcN (GlcNAc) GlcN sulfate salt (GlcN.S) and covalent glucosamine sulfates (GlcN-SO4).

OBJECTIVES: To investigate, in chondrocyte cultures under conditions for maximizing responses in proliferation and proteoglycan (PG) synthesis, the effects of glucosamine hydrochloride (GlcN.HCl) and glucosamine sulfate (GlcN.S) salts, N-acetyl glucosamine (GlcNAc), and covalently substituted GlcN-X,Y,Z(SO(4))(n) (general formula). METHODS: Bovine articular chondrocytes (BAC) were studied under anchorage-independent (AI, alginate beads) and anchorage-dependent (AD, plastic surface) conditions. Differentiation markers were evaluated (e.g., cartilage-specific (V+C)(-) fibronectin). Varying concentrations of GlcN.HCl, GlcN.S, GlcNAc and GlcN sulfated at positions -2, -3, -6, (-2,3), (-3,6) and (-3,4,6), were tested. Cell proliferation, DNA synthesis and [(35)S]-sulfate incorporation into newly synthesized PG were determined. RESULTS: Increasing GlcN.HCl or GlcN.S concentrations gave decreasing net PG synthesis. Compounds showed more pronounced effects in AD cultures (expressing the V(-)C(+) fibronectin isoform) compared to AI cultures ((V+C)(-) isoform). Addition of GlcN.HCl or GlcN.S gave a concentration-dependent decrease in BAC proliferation, partially prevented by glucose (Glc). GlcNAc was not inhibitory. Addition of GlcN-2-SO(4) or GlcN-2,6-diSO(4) did not affect proliferation or DNA synthesis. The other GlcN-sulfates gave varying inhibitory effects, which for GlcN-3-SO(4) were reversed by inosine. CONCLUSIONS: The free amino group of GlcN seems responsible for inhibition of chondrocyte proliferation and PG synthesis. These effects were greater under higher concentrations of GlcN in AD vs AI conditions. GlcN.HCl behaves similarly to GlcN.S, but differential effects with GlcN-X,Y,Z(SO(4))(n) isomers were observed. Acetylation or sulfation of the GlcN amino group reverses or partially reverses, respectively, anti-proliferative effects of GlcN. Sulfation of GlcN, at positions 3 and 6 results in complex effects on AC proliferation and PG synthesis.

Glucosamine therapy for treating osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is the most common form of arthritis, and it is often associated with significant disability and an impaired quality of life. OBJECTIVES: To review all randomized controlled trials (RCTs) evaluating the effectiveness and toxicity of glucosamine in OA. SEARCH STRATEGY: We searched MEDLINE, PREMEDLINE, EMBASE, AMED, ACP Journal Club, DARE, CDSR, and the CCTR. We also wrote letters to content experts, and hand searched reference lists of identified RCTs and pertinent review articles. All searches were updated in January 2005. SELECTION CRITERIA: Relevant studies met the following criteria: 1) RCTs evaluating the effectiveness and safety of glucosamine in OA, 2) Both placebo controlled and comparative studies were eligible, 3) Both single blinded and double blinded studies were eligible. DATA COLLECTION AND ANALYSIS: Data abstraction was performed independently by two investigators and the results were compared for degree of agreement. Gotzsche's method and a validated tool (Jadad 1996) were used to score the quality of the RCTs. Continuous outcome measures were pooled using standardized mean differences (SMD) as the measure of effect size. Dichotomous outcome measures were pooled using relative risk ratios (RR). MAIN RESULTS: Analysis restricted to eight studies with adequate allocation concealment failed to show benefit of glucosamine for pain and WOMAC function. Collectively, the 20 analyzed RCTs found glucosamine favoured placebo with a 28% (change from baseline) improvement in pain (SMD -0.61, 95% CI -0.95, -0.28) and a 21% (change from baseline) improvement in function using the Lequesne index (SMD -0.51 95% CI -0.96, -0.05). However, the results are not uniformly positive, and the reasons for this remain unexplained. WOMAC pain, function and stiffness outcomes did not reach statistical significance. In the 10 RCTs in which the Rotta preparation of glucosamine was compared to placebo, glucosamine was found to be superior for pain (SMD -1.31, 95% CI -1.99, -0.64) and function using the Lequesne index (SMD -0.51, 95% CI -0.96, -0.05). Pooled results for pain (SMD -0.15, 95% CI -0.35, 0.05) and function using the WOMAC index (SMD 0.03, 95% CI -0.18, 0.25) in those RCTs in which a non-Rotta preparation of glucosamine was compared to placebo did not reach statistical significance. In the four RCTs in which the Rotta preparation of glucosamine was compared to an NSAID, glucosamine was superior in two, and equivalent in two. Two RCTs using the Rotta preparation showed that glucosamine was able to slow radiological progression of OA of the knee over a three year period (SMD 0.24, 95% CI 0.04, 0.43). Glucosamine was as safe as placebo in terms of the number of subjects reporting adverse reactions (RR=0.97, 95% CI, 0.88, 1.08). AUTHORS' CONCLUSIONS: This update includes 20 studies with 2570 patients. Pooled results from studies using a non-Rotta preparation or adequate allocation concealment failed to show benefit in pain and WOMAC function while those studies evaluating the Rotta preparation show that glucosamine was superior to placebo in the treatment of pain and functional impairment resulting from symptomatic OA. WOMAC outcomes of pain, stiffness and function did not show a superiority of glucosamine over placebo for both Rotta and non-Rotta preparations of glucosamine. Glucosamine was as safe as placebo.

Positive effect of etidronate therapy is maintained after drug is terminated in patients using corticosteroids.

Following a 52-wk randomized controlled trial of intermittent cyclic etidronate therapy in patients using corticosteroids, we performed a 52-wk open-label trial of calcium alone in 114 corticosteroid-treated patients to determine whether the beneficial effect of etidronate is maintained after the drug is discontinued. All patients were given 500 mg/d of elemental calcium. Sixty-one and 53 patients made up the former placebo and etidronate groups, respectively. A total of 89 (98%) of patients in the former placebo and etidronate groups remained on corticosteroids throughout the second year. The mean (SE) percentage change in bone mineral density of the lumbar spine, femoral neck, and trochanter were compared between groups. The difference between groups in mean percentage change from baseline (wk 0, initiation of etidronate or placebo therapy) in the bone density of the lumbar spine, femoral neck, and trochanter, following 104 wk, was 3.8 (0.9), 3.0 (1.1), and 4.3 (1.1), respectively (p < 0.05, all sites), in favor of the former etidronate group. While not significant, the former placebo group demonstrated a slightly larger rate of decline in bone density over the second year than the former etidronate group at all three sites. Following the discontinuation of etidronate therapy, there was no accelerated bone loss and there was evidence of a residual protective effect in both the lumbar spine and femoral neck for up to 1 yr posttreatment.

Glucosamine therapy for treating osteoarthritis.

BACKGROUND: Osteoarthritis (OA) is the most common form of arthritis, and it is often associated with significant disability and an impaired quality of life. OBJECTIVES: To review all randomized controlled trials (RCTs) evaluating the effectiveness and toxicity of glucosamine in osteoarthritis (OA). SEARCH STRATEGY: We searched MEDLINE, Embase, and Current Contents up to November 1999, and the Cochrane Controlled Trials Register. We also wrote letters to content experts, and hand searched reference lists of identified RCTs and pertinent review articles. SELECTION CRITERIA: Relevant studies met the following criteria: 1) RCTs evaluating the effectiveness and safety of glucosamine in OA, 2) Both placebo based and comparative studies were eligible, 3) Both single blinded and double-blinded studies were eligible. DATA COLLECTION AND ANALYSIS: Data abstraction was performed independently by two investigators and the results were compared for degree of agreement. Gotzsche's method and a validated tool (Jadad 1995) were used to score the quality of the RCTs. Continuous outcome measures were pooled using standardized mean differences. Dichotomous outcome measures were pooled using Peto Odds Ratios. MAIN RESULTS: Collectively, the 16 identified RCTs provided evidence that glucosamine is both effective and safe in OA. In the 13 RCTs in which glucosamine was compared to placebo, glucosamine was found to be superior in all RCTs, except one. In the four RCTs in which glucosamine was compared to an NSAID, glucosamine was superior in two, and equivalent in two. REVIEWER'S CONCLUSIONS: Further research is necessary to confirm the long term effectiveness and toxicity of glucosamine therapy in OA. Most of the trials reviewed only evaluated the Rotta preparation of glucosamine sulfate. It is not known whether different glucosamine preparations prepared by different manufacturers are equally effective in the therapy of OA.

Differential use of Alcian blue and toluidine blue dyes for the quantification and isolation of anionic glycoconjugates from cell cultures: application to proteoglycans and a high-molecular-weight glycoprotein synthesized by articular chondrocytes.

Alcian blue and toluidine blue dyes form complexes with anionic glycoconjugates (AG) such as proteoglycans (PG) and glycosaminoglycans (GAG). However, the Alcian blue-AG complexes do not readily dissociate, while the toluidine blue-AG complexes do so in salt solutions. This differential dissociation of the dye-AG complexes has been utilized in the analysis and isolation of radiolabeled AG elaborated by articular chondrocyte cultures incubated with the radiolabeled precursors of AG. For the rapid quantification of newly synthesized (35)S-labeled PG, small replicate aliquots of the radiolabeled culture media were applied directly to cellulose acetate strips, stained with Alcian blue and the stained immobilized radiolabeled PG was quantified by liquid scintillation counting. Comparison of anionic glycoconjugates quantified in the culture media employing toluidine blue and Alcian blue staining on cellulose acetate trips gave similar results. Staining on cellulose acetate strips using these two dyes is particularly suited for the simultaneous processing of large numbers of samples, as illustrated by the screening of the effects of biological materials and drugs on AG synthesis, in cultures labeled with [(35)S]-sulfate and [(3)H]-glucosamine. The Alcian blue and toluidine blue precipitation methods yielded similar results for the total AG recovered from the media of TGF-beta-stimulated chondrocytes. Electrophoretic analysis of toluidine blue- and Alcian blue-precipitated AG followed by autoradiography and Alcian blue staining in combination with silver nitrate demonstrated that both dyes yielded similar pattern of bands on gels. However, some AG from Alcian blue precipitate did not enter the gel, suggesting incomplete dissociation of Alcian blue-AG complex. The application of the toluidine blue precipitation method, in combination with enzymatic digestion of the GAG chains of the PGs, is illustrated by the isolation of a non-PG high-molecular-weight AG, as well as the PGs from the media of chondrocyte cultures stimulated by TGF-beta.

Thrombotic thrombocytopenic purpura as an initial presentation of limited systemic sclerosis.

Thrombotic thrombocytopenic purpura (TTP) is a rare complication of scleroderma (systemic sclerosis, SSc). In the 5 reports documenting the association of TTP and SSc, the TTP syndrome developed on a background of well established SSc. We describe a 51-year-old woman with a 5 month history of an evolving connective tissue disease syndrome who presented initially with TTP, followed 4 months later by limited cutaneous SSc and Raynaud's phenomenon.

Comparison of the combined cortical thickness of the second metacarpal with Sharp's method for scoring hand microradiographs in rheumatoid arthritis.

OBJECTIVE: To compare the correlation and specificity of the combined cortical thickness of the second metacarpal (CCT-MC) with Sharp's method (SM) for scoring joint erosions and joint space narrowing in rheumatoid arthritis (RA) and to compare the degree of interobserver agreement between the 2 methods. METHODS: Hand microradiographs of 22 women with RA, functional classes III and IV, were scored independently by 3 rheumatologists using the CCT-MC and the CCT of the middle phalanx and SM. RESULTS: (1) There was a highly significant correlation between the total SM score and the CCT-MC for the 3 observers (r = 0.61, p = 0.0026), but not between the CCT of the middle phalanx and SM (r = 0.15, p = 0.53). There was a lower degree of agreement between the observers for SM erosion scores compared to the CCT-MC (intraclass correlation 0.88 for the CCT-MC and 0.63 for the SM); (2) Both joint space narrowing and erosion scores correlated highly with the CCT-MC (r = -0.60, p = 0.004; and r = -0.51, p = 0.014, respectively); (3) CCT-MC measurements are more closely related to the inner (d) as opposed to the outer (D) diameter of the 2nd metacarpal; (4) The mean time to obtain the CCT-MC score was 3.43 min (SD = 1.38) versus 9.83 min (SD = 3.20) for SM (p = 0.0001); (5) the derivative, (D2-d2)/D2, was significantly correlated with SM (r = -0.72, p = 0.0002) and its erosion and joint space narrowing components (r = -0.63, p = 0.0019; and r = -0.71, p = 0.0002, respectively). CONCLUSION: The CCT-MC is a rapid, practical method with higher agreement among observers compared to SM and correlates highly with SM scores for joint damage in RA. CCT-MC appears to have a higher degree of specificity than other sites for CCT measurement. The CCT-MC is more closely related to the inner diameter than the outer diameter, which supports the notion that the principal site of accelerated bone loss due to RA in the hand occurs at the endosteal surface. The CCT-MC should be further assessed with respect to monitoring radiological progression in RA.

Anionic glycoconjugates from differentiated and dedifferentiated cultures of bovine articular chondrocytes: modulation by TGF-beta.

Primary, high density bovine articular chondrocyte (BAC) cultures, stimulated with transforming growth factor-beta-1, elaborated a high molecular weight anionic glycoconjugate, kDa 540, which does not contain glycosaminoglycan chains (Chan and Anastassiades, 1996). The effect of exogenously added transforming growth factor-beta-1 on the elaboration of the high molecular weight glycoconjugate and of proteoglycans was studied during dedifferentiation of the chondrocytes, utilizing a serial subculture technique under anchorage-dependent conditions, up to four subcultures. The high molecular weight glycoconjugate was detected in the media of all growth-factor-stimulated chondrocyte subcultures, as well as stimulated primary cultures, but not in unstimulated primary cultures or subcultures. By contrast, a large proteoglycan, was only secreted by primary cultures and first subcultures, whether treated with transforming growth factor-beta-1 or untreated. This proteoglycan contained mostly chondroitin sulfate chains, whose hydrodynamic size was increased by the addition of transforming growth factor-beta-1. Further, the pattern of the proteoglycans appearing in the media of subcultures 2-4 was influenced by the addition of transforming growth factor-beta-1, so that while these control subcultures elaborated both the large and small chondroitin sulfate proteoglycans, the equivalent stimulated subcultures elaborated only intermediate sized chondroitin sulfate proteoglycan(s). These results suggest that while dedifferentiation of articular chondrocytes, achieved by subculturing, strongly modulates the effect of exogenously added transforming growth factor-beta-1 on the type of proteoglycan elaborated, the process of dedifferentiation does not influence the transforming-growth-factor-beta-dependent synthesis of the high molecular weight anionic glycoconjugate.

Exogenous glycosaminoglycans (GAG) differentially modulate GAG synthesis by anchorage-independent cultures of the outer cells from neonatal rat calvaria in the absence and presence of TGF-beta.

In anchorage-dependent (AD) cultures of the outer cell population (OCP) from neonatal rat calvaria, transforming growth factor-beta 1 (TGF-beta) specifically upregulated the synthesis of chondroitin sulfate (CS) proteoglycan (PG) and uncoupled the inhibitory effect of increasing cell density on CS PG synthesis (reference #30). Utilizing the same cell population, we have further examined the possibility that glycosaminoglycans (GAG) known to be synthesized and secreted by bone cells might exert feedback effects on GAG synthesis and/or its stimulation by TGF-beta. Although addition of TGF-beta alone stimulated net synthesis of HA and CS in both AD and anchorage-independent (AI) cultures, significant alterations of basal and TGF-beta-stimulated GAG synthesis by exogenous GAGs were observed only in AI cultures. In AI cultures exogenously added hyaluronic acid (HA) markedly enhanced the basal synthesis of HA and CS while heparin (H) suppressed the basal synthesis of HA, CS as well as dermatan sulfate (DS). Also, the addition of HA markedly potentiated the stimulation by TGF-beta of HA and CS synthesis as did heparan sulfate (HS) for CS and DS synthesis. H suppressed the stimulation of the synthesis of HA, CS and DS by TGF-beta. Overall, our results indicate specific effects of individual GAGs on basal and TGF-beta-stimulated GAG synthesis in OCP cultures. We suggest that some of the GAGs in the OCP microenvironment (which with the exception of HA are covalently linked to protein cores of secreted PGs), acting in concert with TGF-beta, may serve as an amplification system for upregulating GAG synthesis in the rapidly growing neonatal calvarium.

Isolation and partial characterization of a high molecular weight anionic glycoconjugate from transforming growth factor-beta treated bovine articular chondrocyte cultures.

A high molecular weight anionic glycoconjugate was isolated from the media of the transforming growth factor-beta treated chondrocyte cultures by anion-exchange chromatography on DEAE-Sephacel and Mono Q columns and was partially characterized. This high molecular weight anionic glycoconjugate was not detected in the non-treated (control) cultures. Characterization studies showed that the glycoconjugate is a non-reducible, non-collagenous glycoprotein containing O-linked, N-linked, and sialic acid substituted carbohydrate units. The isolated glycoconjugate stained "blue" with Stains All and migrated as a single band on sodium dodecyl sulfate gradient gels (2.5-10% acrylamide - diallyl tartardiamide) at an estimated molecular weight of 540 000. Amino acid and amino sugar analyses showed that it is rich in aspartic acid--asparagine, glutamic acid--glutamine, alanine, proline, and glycine, and contains galactosamine and glucoasmine. This transforming growth factor-beta inducible glycoprotein may be involved in cell differentiation and in the cartilage repair process. It may also be used as a marker to localize the biological activity of transforming growth factor-beta in articular cartilage.

A "coupled" subchondral bone-articular cartilage tissue culture system for the study of cartilage proteoglycan metabolism.

Current evidence suggests that interactions between the subchondral bone and the articular cartilage of mammalian diarthrodial joints may occur through the action of bone-associated peptide factors. However, there is no suitable organ culture model for studying these interactions. This study defines a long-term tissue culture system where the articular cartilage is coupled to the adjacent subchondral bone obtained from the proximal ends of bovine metacarpals. Autoradiography done over 3 mo., by utilizing [35S]SO4 incorporation into cartilage proteoglycan (PG) and a procedure for cutting non-decalcified bone, demonstrated similar numbers of silver grains over chondrocytes in all cartilage zones, including the bone-cartilage interface. Newly synthesized PG (NSPG) from the cartilage of the "coupled" system over a 3-wk period was primarily of large hydrodynamic size (Kav of 0.34). Comparable bovine articular and nasal cartilage slice systems, incubated for short periods of time, yielded similar and somewhat larger NSPG, respectively. Labeled chondroitin sulphate PG accumulating in the medium of primary chondrocyte monolayer cultures, derived from the cartilage of the coupled system at 0, 1, 2, and 3 wk, revealed two polydisperse subpopulations (Kav of 0.30 to 0.38 and 0.51 to 0.68). We conclude that this coupled bone-cartilage system is viable for prolonged periods, is suitable for studies on the metabolism of articular cartilage PGs, and seems to have some advantages over the cultured articular cartilage slice system.

Rheumatoid hand. Practical approach to assessment and management.

Rheumatoid arthritis is a systemic inflammatory disease with a predilection for the synovial tissues. Its diverse involvement can be demonstrated in the hand, where several anatomical structures can be affected simultaneously. Proper management requires attention to this principle, and a complete diagnostic evaluation will help to identify correctly the cause of the patient's functional limitation and pain. We present a practical approach to managing rheumatoid arthritis in the hand.

A "coupled" subchondral bone-articular cartilage tissue culture system for the study of cartilage proteoglycan metabolism.

Current evidence suggests that interactions between the subchondral bone and the articular cartilage of mammalian diarthrodial joints may occur through the action of bone-associated peptide factors. However, there is no suitable organ culture model for studying these interactions. This study defines a long-term tissue culture system where the articular cartilage is coupled to the adjacent subchondral bone obtained from the proximal ends of bovine metacarpals. Autoradiography done over 3 mo., by utilizing [(35)S]SO4 incorporation into cartilage proteoglycan (PG) and a procedure for cutting non-decalcified bone, demonstrated similar numbers of silver grains over chondrocytes in all cartilage zones, including the bone-cartilage interface. Newly synthesized PG (NSPG) from the cartilage of the "coupled" system over a 3-wk period was primarily of large hydrodynamic size (Kav of 0.34). Comparable bovine articular and nasal cartilage slice systems, incubated for short periods of time, yielded similar and somewhat larger NSPG, respectively. Labeled chondroitin sulphate PG accumulating in the medium of primary chondrocyte monolayer cultures, derived from the cartilage of the coupled system at 0, 1, 2, and 3 wk, revealed two polydisperse subpopulations (Kav of 0.30 to 0.38 and 0.51 to 0.68). We conclude that this coupled bone-cartilage system is viable for prolonged periods, is suitable for studies on the metabolism of articular cartilage PGs, and seems to have some advantages over the cultured articular cartilage slice system.

Stimulatory effect of TGF-beta on anionic glycoconjugate synthesis by rat calvarial cells: specificity, uncoupling of cell density dependence, and modulation by chondroitin sulfate.

Anchorage-dependent cultures of a population of cells derived from the outer part of the rat calvaria demonstrated decreased net accumulation of radiolabeled chondroitin sulfate (CS) and hyaluronic acid (HA) per cell as the cell density of the cultures increased. The addition of TGF-beta 1 resulted in large stimulations of the net CS, but not of the net HA, accumulating in the medium at all cell densities and an abolition of the density-dependent effect. These effects were largely due to increases in newly synthesized CS appearing in the medium. Supplementation of the culture media with CS had complex but relatively small effects on the stimulation of the net accumulation of radiolabeled medium CS by TGF-beta 1. The addition of TGF-beta 1 also resulted in a biphasic effect on cell growth that depended on the plating density, but cell growth differences could not account for the marked stimulation of CS synthesis by TGF-beta 1. Experiments with cycloheximide and beta-xyloside and isolation of the intact anionic glycoconjugates (AG) indicated that although synthesis of core protein was the limiting factor in CS synthesis, TGF-beta 1 stimulated the synthesis of CS chain when sufficient beta-xyloside acceptor was available. The overall results suggest that, in this cell system, the action of TGF-beta 1 on the synthesis of the major extracellular AGs is characterized by a relatively specific upregulation of CS proteoglycan (PG) synthesis and an uncoupling of the inhibitory effect of high cell density on CS PG synthesis.

Pancreatitis arthritis with periarticular fat necrosis.

We describe the case of a 76-year-old man hospitalized for 14 months because of a complicated hip fracture who developed pancreatitis and polyarthritis. He had no evidence of subcutaneous fat necrosis away from his joints and his pancreatitis was virtually asymptomatic otherwise. Polyarthritis is a rare complication of this disorder, and rarer still is polyarthritis without evidence of subcutaneous fat necrosis elsewhere.