Bone marrow lesions, subchondral bone cysts and subchondral bone attrition are associated with histological synovitis in patients with end-stage knee osteoarthritis: a cross-sectional study.

OBJECTIVE: The aim of this study was to examine the osteoarthritis (OA)-related structural changes associated with histological synovitis in end-stage knee OA patients. METHODS: Forty end-stage knee OA patients (female: 88%, mean age: 71.8 y) were enrolled. All participants underwent 3.0-T MRI. The structural changes, such as cartilage morphology, subchondral bone marrow lesion (BML), subchondral bone cyst (SBC), subchondral bone attrition (SBA), osteophytes, meniscal lesion and synovitis, were scored using the whole-organ MRI scoring (WORMS) method. Synovial samples were obtained from five regions of interest (ROIs) of the knee joint during total joint replacement surgery. The associations between the histological synovitis score (HSS) and WORMS or the synovial expression levels of cyclooxygenase (COX)-2, interleukin (IL)-1ß, IL-6 and transforming growth factor (TGF)-ß were examined using Spearman's correlation coefficient. RESULTS: Among the seven OA-related structural changes, the BML, SBC, SBA and synovitis were significantly associated with the HSS (r = 0.33, 0.35, 0.48 and 0.36, respectively), while other morphological changes were not. Although synovial COX-2, IL-1ß or IL-6 expression levels were not associated with the HSS, the synovial TGF-ß expression levels were associated with the HSS. CONCLUSION: The presence of BML, SBC and SBA was associated with histological synovitis in end-stage knee OA patients.

The degeneration and destruction of femoral articular cartilage shows a greater degree of deterioration than that of the tibial and patellar articular cartilage in early stage knee osteoarthritis: a cross-sectional study.

OBJECTIVE: The aim of the present study was to examine whether the degenerative and morphological changes of articular cartilage in early stage knee osteoarthritis (OA) occurred equally for both femoral- and tibial- or patellar- articular cartilage using magnetic resonance imaging (MRI)-based analyses. DESIGN: This cross-sectional study was approved by the ethics committee of our university. Fifty patients with early stage painful knee OA were enrolled. The patients underwent 3.0 T MRI on the affected knee joint. Healthy volunteers who did not show MRI-based OA changes were also recruited as controls (n = 19). The degenerative changes of the articular cartilage were quantified by a T2 mapping analysis, and any structural changes were conducted using Whole Organ Magnetic Resonance Imaging Score (WORMS) technique. RESULTS: All patients showed MRI-detected OA morphological changes. The T2 values of femoral condyle (FC) (P < 0.0001) and groove (P = 0.0001) in patients with early stage knee OA were significantly increased in comparison to those in the control, while no significant differences in the T2 values of patellar and tibial plateau (TP) were observed between the patients and the control. The WORMS cartilage and osteophyte scores of the femoral articular cartilage were significantly higher than those in the patellar- (P = 0.001 and P = 0.007, respectively) and tibial- (P = 0.0001 and P < 0.0001, respectively) articular cartilage in the patients with early stage knee OA. CONCLUSIONS: The degradation and destruction of the femoral articular cartilage demonstrated a greater degree of deterioration than those of the tibial- and patellar- articular cartilage in patients with early stage knee OA.

Combinatory effects of androgen receptor deficiency and hind limb unloading on bone.

Male sex hormones play a critical role in regulation of bone metabolism. In male mice lacking androgen receptor (AR), osteopenia and high turnover state in bone remodeling have been reported. However, androgen receptor's role in disuse-induced osteopenia is not known. Therefore, we examined the effects of AR deficiency on unloading-induced bone loss. Wild type or androgen receptor deficient mice (ARKO) were subjected to hind limb unloading (HU) or normal housing (Control). The groups of mice were as follows; wild type control mice (Group WT-Cont), ARKO control mice (Group ARKO-Cont), wild type HU mice (Group WT-HU), and ARKO-HU mice (Group ARKO-HU). HU reduced cancellous bone mass in ARKO (ARKO-HU) by about 70% compared to ARKO-Cont and this reduction rate was over two-fold more than that of wild type (WT-HU) (reduction by less than 30% compared to WT-Cont). Combination of ARKO and HU (ARKO-HU) resulted in the least levels of cortical bone mass and bone mineral density among the four groups. ARKO-HU group indicated the highest levels of systemic bone resorption marker, deoxypyridinoline. Osteoclast development levels in the cultures in ARKO-HU derived bone marrow cells were the highest among the four groups. These data suggest that combination of androgen receptor deficiency and hind limb unloading results in exacerbation of disuse-induced osteopenia due to the enhanced levels of bone resorption.

[Pulmonary atresia with intact ventricular septum showing Fontan-like circulation after biventricular repair].

A 6-year-old girl was referred to our institute for cardiac evaluation. She had been diagnosed as pulmonary atresia with intact ventricular septum (PAIVS) at 16 days after birth and she had underwent balloon atrial septostomy and bilateral Blalock-Taussig shunts. A cardiac catheterization at 5 months showed that her right ventricular end diastolic volume was 58% of normal, the Z value (standard deviation units) of the diameter of the tricuspid valve was -3.3, and a biventricular repair was performed. After the operation, she suffered from severe congestive heart failure for 10 months. A cardiac catheterization at the age of 6 years demonstrated that the pulmonary blood flow was generated during the diastolic phase like Fontan circulation. Although biventricular repair had been performed at 5 months, the circulation may be less advantageous for long term survival than if the patient had undergone the staged Fontan procedure. Careful and continuous hemodynamic assessment is essential for surgical therapy of PAIVS.

Protective effect of ischaemic preconditioning against ischaemia-induced reperfusion injury of skeletal muscle: how many preconditioning cycles are appropriate?

We investigated the efficacy of ischaemic preconditioning (IPC), consisting of repeated brief episodes of vascular occlusion followed by reperfusion, as protection against ischaemia-reperfusion injury of skeletal muscle, using a rat amputation-like model. Wistar rats underwent temporary amputation at the level of the femur, excluding the femoral vessels. The femoral artery and vein were clamped for 4h, using a micro-clamp, in the groups exposed to ischaemia. The rats were randomly divided into eight groups: a control (C) group (n = 7) with non-amputated and non-ischaemic hind limbs; a sham control (SC) group (n = 7) with amputated but non-ischaemic hind limbs; an ischaemia-reperfusion (IR) group (n = 7) with amputated and ischaemic hind limbs; and five IPC groups (n = 7 in each) with hind limbs that were subjected to 4h of ischaemia after one to five cycles of brief ischaemia and reperfusion for 10 min each, respectively. All rats were sacrificed 24h after reperfusion. The viability of the anterior tibial muscles was evaluated using nitroblue tetrazolium staining. The total viable area ratio (T-VAR) of the muscle tissue was calculated in each animal as follows: T-VAR\total viable area/total slice areae 100%. The T-VAR values of the eight groups were as follows: C group, 100% +/- 0%; SC group, 100% +/- 0%; IR group, 73.5% +/- 1.7%; IPC1 group, 79.4% +/- 6.5%; IPC2 group, 70.5% +/- 6.2%; IPC3 group, 90.6% +/- 2.8%; IPC4 group, 90.0% +/- 1.6%; and IPC5 group, 87.8% +/- 1.8%. The T-VARs in the IPC3, IPC4 and IPC5 groups were significantly higher (alpha < 0.01) than those in the IR group. In contrast, there were no significant differences between the T-VARs of the IPC1 and IPC2 groups and those of the IR group. In conclusion, three to five cycles of IPC could protect skeletal muscle against ischaemia. 2002 The British Association of Plastic Surgeons.

Chemokines regulate IL-6 and IL-8 production by fibroblast-like synoviocytes from patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is characterized by proliferation of synoviocytes that produce inflammatory cytokines and chemokines. The expressed chemokines are thought to be involved in the migration of inflammatory cells into the synovium. In this study we show that CCL2/monocyte chemotactic protein-1, CCL5/RANTES, and CXCL12/stromal cell-derived factor-1 enhanced IL-6 and IL-8 production by fibroblast-like synoviocytes (FLS) from patients with RA, and their corresponding receptors, CCR2, CCR5, and CXCR4, respectively, were expressed by RA FLS. The chemokines stimulated RA FLS more effectively than skin fibroblasts. Culture with CCL2 enhanced phosphorylation of extracellular signal-related kinase 1 (ERK1) and ERK2, but not phosphorylation of p38 or Src. Moreover, activation of ERK1/2 was inhibited by pertussis toxin, a G(i)-coupled protein inhibitor, and RS-504393, CCR2 antagonist, suggesting that ERK1/2 was activated by CCL2 via CCR2 and G(i)-coupled protein. On the other hand, CCL2, CCL5, and CXCL12 were expressed on RA FLS, and their production was regulated by TNF-alpha, IL-1beta, and TGF-beta1. Our results indicate that the chemokines not only play a role in inflammatory cell migration, but are also involved in the activation of FLS in RA synovium, possibly in an autocrine or paracrine manner.

Free vascularized fibular graft vs. Ilizarov method for post-traumatic tibial bone defect.

From 1991 to 1996, four free vascularized fibular grafts (FVFG) and four callus distraction (CD) techniques were performed for post-traumatic tibial defects at the authors' institute. They attempted to discern any differences of results between FVFGs and CDs for post-traumatic tibial defects. The mean defect length of the FVFG and CD groups were 7.3 cm and 4.6 cm, respectively (p < 0.05). They selected as contributing factors: external fixation time, complication rate, hospital charge, union rate, and functional score (Puno's criteria), in order to compare the treatment of FVFG with that of CD. The external fixation times of the FVFG and CD groups were 176 days and 261 days, respectively. One septic non-union after refracture of the grafted fibula occurred in the FVFG group. Two non-unions (50 percent) at the docking site occurred in the CD group. The mean total costs of the FVFG and CD groups were 7,398,536 yen (US $68,505) and 11,798,153 yen(US $109,242), respectively. The union rates of both groups were 75 percent and 100 percent, respectively. The mean functional scores of both groups were 69.5 and 88.8 points, respectively. The functional results of the FVFG group were as follows: one patient showed good results; one, fair; and two, poor. The functional results of the CD group were as follows: two patients showed excellent results; one, good; and one, fair. Both the costs and the functional outcomes between the two groups did not significantly differ. No clear differences between the two treatment groups could be determined. However, many more cases are needed to establish statistically significant differences between both methods.

Contributing factors influencing the functional outcome of floating knee injuries.

The purpose of the present study was to retrospectively review the floating knee injuries treated at our institute and to determine various factors, such as severity of soft-tissue or skeletal injuries, site of fractures, and treatment methods that may significantly influence the final functional result in these injuries. Between 1986 and 1996, 65 patients with 66 floating knee injuries were treated in our institution. Among 66 fractures of the femur, 19 (29%) were open. There were 43 open tibial fractures. Fifty cases were Fraser type I floating knee fractures, 7 were type IIa, 2 were type IIb, and 7 were type IIc. In 63 cases (95%), both bones had been surgically stabilized with interlocked nails, Ender pins, plates, screws with/without pinning, or external fixations. Final functional results were evaluated according to Karlström and Olerud's criteria. Satisfactory results were rated as cases with excellent or good results. The mean follow-up time was 16.6 months range, (12-50 months). We assessed various factors influencing functional results, including Fraser type, severity of open injury grade (Gustilo) in both fractures, combination of open/closed injuries, fracture types (AO/ASIF type), existence of multiple trauma, neurovascular injuries, polyskeletal trauma, and stabilizing method or operation timing of both fractures. Satisfactory rates in Fraser type I and type II were 64% and 25%, respectively (P= .02). The satisfactory rate in closed, grade I+II, and grade III injuries of the femoral fractures was 53.2%, 81.8%, and 25%, respectively (grade I+II vs. grade III: P < .03). There were no significant correlations between the functional result and the following factors: soft-tissue injuries of the tibia; the fracture pattern of both fractures; the combination of open/closed injuries in each fracture; injury severity score; the existence of neurovascular injuries and double femoral fractures; treatment methods; and operation timing. Severity of damage to the knee joint and open injuries in the thigh were found to be significant factors contributing to the functional outcome in floating knee injuries.

A novel phosphodiesterase type 4 inhibitor, YM976 (4-(3-chlorophenyl)-1,7-diethylpyrido[2,3-d]pyrimidin-2(1H)-one), with little emetogenic activity.

We synthesized a novel phosphodiesterase type 4 (PDE4) inhibitor, YM976, that is structurally different from the other PDE4 inhibitors like rolipram. In the present study, the pharmacological profile of YM976 was investigated. YM976 exhibited a strong and competitive inhibition against PDE4 purified from human peripheral leukocytes with an IC(50) of 2.2 nM. IC(50) values of rolipram and RP73401 were 820 and 0.43 nM, respectively. Test compounds had no effects on the other PDE isozymes, PDE1, -2, -3, and -5. YM976 potentiated prostaglandin E(2)-induced cAMP accumulation in a human mononuclear cell line, U937, and inhibited tumor necrosis factor-alpha production from human peripheral blood mononuclear cells stimulated by lipopolysaccharide. Anti-inflammatory activities of PDE4 inhibitors were compared in rat carrageenan-induced pleurisy models. YM976, rolipram, and RP73401 inhibited the cell infiltration into the pleural cavity with oral ED(30) values of 9.1, 10, and 7.4 mg/kg, respectively. YM976 produced no emesis up to 10 mg/kg, whereas rolipram and RP73401 induced emesis at oral doses of 3 mg/kg. To evidence the dissociation of anti-inflammatory activity from emesis, the anti-inflammatory effect of YM976 was examined in ferrets. YM976 dose dependently reduced carrageenan-induced leukocyte infiltration at the doses of 1, 3, and 10 mg/kg, p.o. On the other hand, rolipram failed to show obvious inhibition at doses that do not induce emesis. In conclusion, YM976 is a novel and orally active PDE4 inhibitor and possesses a good separation of emetogenicity from anti-inflammatory activity.

Time course of superoxide anion radicals generation in two ischaemia-reperfusion models: comparison between hindlimb replant model and isolated rectus femoris muscle model.

We examined differences in superoxide radical (O(2)(-)) production between a hindlimb replant model and isolated rectus femoris muscle model using rabbits. Using Japanese white rabbit hindlimbs, we made limb replant models (LR group: n = 10) and isolated rectus femoris muscle models (IM group: n = 8) by temporary 4-h clampings of femoral vessels and nutrient vessels, respectively. For sham control subjects, the same surgical procedures with no clampings in both models were done (Control-LR: n = 7, Control-IM: n = 6). The measurement of O(2)(-)was performed by our chemiluminescence (CLN) method. In both models, reperfused blood samples were collected before reperfusion, and 5, 15, 30 and 60 min after reperfusion, and CLN was measured. We defined the superoxide index (SI) in each individual specimen as post-reperfusion CLN/pre-reperfusion CLN. The time course of SI in the Control-LR group was significantly higher than that of SI in the Control-IM group (P< 0.05). There was no significant difference between the time course of SI in the LR group and that of SI in the IM group. Both the limb replant model and isolated muscle model are applicable for the evaluation of radical formation in the reperfused stage though there are potential differences between the two models caused by the surgical procedures themselves.

Mitogenic activity of endothelin on human cultured prostatic smooth muscle cells.

The effects of endothelins on human prostatic smooth-muscle cell growth were examined. Endothelin-1 and endothelin-3 induced a concentration-dependent increase in DNA synthesis and also promoted cell growth. Use of subtype selective antagonists BQ-123 ((cyclo(D-Trp-D-Asp(ONa)-Pro-D-Val-Leu); endothelin ET(A) receptor selective) and BQ-788 ((N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-methyl Leu-D-Trp-(COOMe)-D-Nle-ONa); endothelin ET(B) receptor selective), indicated that mitogenic effects of endothelin were mediated through activation of both endothelin ET(A) and ET(B) receptors. The mitogenic effects of endothelin-1 and endothelin-3 were significantly inhibited by pretreatment of the cells with pertussis toxin. However, mitogenesis due to basic fibroblast growth factor was not affected. In conclusion, endothelin has mitogenic effects on human prostatic smooth muscle cells through activation of both endothelin ET(A) and ET(B) receptors via different signalling pathways from basic fibroblast growth factor. This may contribute to smooth muscle hyperplasia associated with benign prostatic hyperplasia.

Endothelin receptors and their cellular signal transduction mechanism in human cultured prostatic smooth muscle cells.

1. Endothelin (ET) receptors, and their cellular signal transduction mechanism, were characterized in a primary culture of human prostatic smooth muscle cells (HP cell). 2. [125I]-ET-1 and [125I]-ET-3 binding studies revealed that both ETA and ETB receptors were present in the HP cells, and the ratio of ETA to ETB receptors was 1.4:1. 3. Analysis of ET receptor mRNA by reverse transcription-polymerase chain reaction also demonstrated that HP cells express both ETA and ETB receptors. 4. ET-1 and ET-3 increased intracellular free Ca2+ concentration ([Ca2+]i) in the HP cells in a concentration-dependent manner. Use of subtype selective antagonists BQ-123 and BQ-788, indicated that both ETA and ETB receptors were coupled to an increase in [Ca2+]i. 5. Pretreatment of the cells with pertussis toxin resulted in a significant but partial attenuation of the [Ca2+]i increase mediated through the ETA and ETB receptors. However, sensitivity to pertussis toxin (PTX) was significantly different between them. 6. In conclusion, HP cells possess ETA and ETB receptors. Further, these two endothelin receptor subtypes evoke an increase in [Ca2+]i possibly via the action of different GTP-binding proteins.

Antagonistic effect of YM022, an antiulcer agent in rats, on human cholecystokinin (CCK)B/gastrin receptor.

We recently isolated a cDNA clone for the human cholecystokinin (CCK)B/gastrin receptor and permanently expressed this receptor cDNA in NIH-3T3 cells. [125I]CCK-8 specifically bound to the membrane of the transfectant, and this binding was displaced by unlabeled CCK-8 with an IC50 of 0.32 nM. Treatment of these cells with CCK-8 increased the intracellular Ca2+ concentration with an EC50 of 0.30 nM. Using these cells expressing functional human CCKB/gastrin receptors, we investigated the pharmacological properties of (R)-1-[2,3-dihydro-1-(2'-methylphenacyl)-2-oxo-5-phenyl-1H-1, 4-benzodiazepin-3-yl]-3-(3-methylphenyl) urea (YM022), a potent and selective CCKB/gastrin receptor antagonist in rats. YM022 potently inhibited [125I]CCK-8 binding to the membrane with an IC50 of 55 pM and CCK-8-induced Ca2+ mobilization with that of 7.4 nM. On the other hand, its racemate and enantiomer more weakly inhibited this binding (IC50 of 110 pM and 11 nM, respectively) and Ca2+ mobilization (IC50 of 18 nM and 94 nM, respectively). These results indicate that YM022 stereoselectively recognizes the human CCKB/gastrin receptor as a potent antagonist and that the established transfectant is useful for characterization of human CCKB/gastrin-receptor ligands.

Oxytocin receptors expressed and coupled to Ca2+ signalling in a human vascular smooth muscle cell line.

1. In a human vascular smooth muscle cell line (HVSMC), binding experiments with [3H]-arginine8-vasopressin (AVP) have shown the existence of a homogeneous population of binding sites with affinity (Kd value) of 0.65 nM and a maximum number of binding sites (Bmax) of 122 fmol mg-1 protein. 2. Nonlabelled compounds compete for [3H]-AVP binding in the HVSMC membrane with an order of potency of oxytocin > lyspressin > or = AVP > Thr4, Gly7-oxytocin > (beta-mercapto-beta-beta-cyclopentamethylenepropionyl-O-Me Tyr2, Arg8) vasopressin > desmopressin > OPC21268 > OPC31260. This order was markedly different from that observed in rat vascular smooth muscle cells (A10), a well-established V1A receptor system. 3. In HVSMC both oxytocin and AVP increased inositol 1,4,5-trisphosphate (IP3) production and [Ca2+]i response, but the efficacy of the responses was greater for oxytocin than AVP. 4. Reverse transcription-polymerase chain reaction (RT-PCR) assay detected only oxytocin receptor but not V1A or V2 receptors in HVSMC, whereas only V1A receptors were found in A10 cells. 5. In conclusion, in HVSMC only oxytocin receptors are expressed among the vasopressin receptor family, and they coupled to phosphatidyl inositol (PI) turnover/Ca2+ signalling. This unexpected observation should provide new insight into the functional role of the oxytocin receptor in a human vascular smooth muscle cell line.

Characterization of muscarinic cholinoceptor in primary culture of smooth muscle cells from human prostate.

We obtained a primary culture of prostatic cells by an explant method from patients with benign prostatic hypertrophy (BPH). Ultrastructural morphology and growth characteristics of these cells conformed to those reported for smooth muscle cells isolated from vascular and visceral tissue sources. The cells retained their original character including the presence of androgen receptor, acid phosphatase and normal chromosomal number. [3H]-methyl-quinuclidinyl benzilate (QNB) saturation experiments showed the existence of a homogeneous population of binding sites with a high affinity and low capacity (KD = 0.17 +/- 0.05 nM., Bmax = 15,000 sites per cell). Inhibition of [3H]-methyl-QNB binding by nonlabelled compounds showed these [3H]-methyl-QNB binding sites to be M2 muscarinic cholinoceptors. cAMP formation induced by forskolin and isoproterenol was inhibited by carbamoyl choline and oxotremorine. These results suggest that prostatic smooth muscle cells contain M2 muscarinic cholinoceptors and that these cholinoceptors couple adenylate cyclase inhibition.

Characterization of YM022: its CCKB/gastrin receptor binding profile and antagonism to CCK-8-induced Ca2+ mobilization.

We investigated the antagonistic activity of (R)-1-[2,3-dihydro-1-(2'- methylphenacyl)-2-oxo-5-phenyl-1H-1,4-benzodiazepin-3-yl]-3- (3-methylphenyl) urea (YM022), a benzodiazepine derivative, at CCKB/gastrin receptors. This compound potently inhibited [125I]CCK-8 binding to rat brain CCKB/gastrin receptors with a Ki value of 0.26 nM, but it showed weak affinity for rat pancreas CCKA receptors (Ki = 270 nM). Selectivity for CCKB/gastrin receptors was 1000-fold greater than that for CCKA receptors. Changes in intracellular free Ca2+ concentration ([Ca2+]i) in response to CCK-8 were measured in a rat anterior pituitary cell line GH3 by fura-2 fluorometry. CCK-8 (1-100 nM) dose-dependently increased [Ca2+]i in these cells, whereas YM022 had no effect on baseline [Ca2+]i even at the highest concentration of 100 nM. YM022 inhibited the mobilization of [Ca2+]i elicited by 10 nM CCK-8 in a concentration-dependent manner with an IC50 value of 4 nM. In conclusion, YM022 is an extremely potent and highly selective antagonist of CCKB/gastrin receptors. This compound is therefore useful for studying the physiological and pharmacological roles of CCKB/gastrin receptors.

N-ethylmaleimide-sensitive mutant (beta Val-153-->Cys) Escherichia coli F1-ATPase: cross-linking of the mutant beta subunit with the alpha subunit.

A beta subunit mutation, beta Val-153-->Cys, in the glycine-rich sequence (phosphate-binding loop) of Escherichia coli F1 was constructed. Like vacuolar-type ATPase, the mutant enzyme was inhibited by N-ethylmaleimide (NEM) and labeled with [14C]NEM. The inhibition and labeling were prevented by ATP. m-Maleimidobenzoyl-N-hydroxysuccinimide (MBS) (3 microM) almost completely inhibited the mutant enzyme, and cross-linked one pair of alpha and beta subunits. These results suggest that the interaction of the domain near beta Val-153 with the alpha subunit is essential for catalytic cooperativity of the enzyme and that beta Val-153 is within 10 A of the alpha subunit.