Avoidance of doxorubicin resistance in osteosarcoma cells using a new quinoline derivative, MS-209

P-glycoprotein (Pgp), a membrane drug efflux pump, is thought to be responsible for the observed drug resistance in osteosarcoma. We have recently developed Pgp-positive, multidrug resistant (MDR) murine osteosarcoma cell lines, which may be suitable models for the study of drug resistance in osteosarcoma. In this study, we investigated the effect of a newly synthesized quinoline compound, MS-209, on the reversal of doxorubicin (DOX) resistance in these cell lines. Three different types of resistance modifying agents (RMAs) as well as MS-209 were studied. These included the calcium channel blocker verapamil, and the immunosuppressive agents cyclosporin A and FK506. The reversal effects of the RMAs on DOX resistance were assessed by the MTT assay. In the absence of RMAs, the MDR osteosarcoma cells were 20-fold more resistant to DOX than the parental cells. When MS-209 was added at a final concentration of 0.1 to 3 microM to the MDR cells, 3-to 74-fold sensitization was observed. A complete reversal (37-fold sensitization) of the resistance was obtained at 1 microM MS-209. This concentration of MS-209 was 3-, 8- and 28-fold more effective than the same concentration of FK506, verapamil and cyclosporin A, respectively. These results indicate that MS-209 may be a more effective RMA, and that DOX resistance in osteosarcoma cells could be reversed by comparatively low doses of MS-209.

Comparison of antiplatelet effects of two nitric oxide-donating agents, FR146801 and FK409

In the present study, we examined the antiplatelet effects of the two nitric oxide (NO)-donating agents, (+/-)-N-[(E)-4-ethyl-3-[(Z)-hydroxyimino]-6-methyl-5-nitro-3-he ptenyl]-3-pyridinecarboxamide (FR146801). a more stable analog of FK409 ((+/-)-(E)-4-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide ), and FK409 in in vitro and in vivo experiments. FR146801 and FK409 inhibited ADP- and collagen-induced platelet aggregation in human and rat platelet-rich plasma in a concentration-dependent manner, however, the inhibitory effect of FR146801 was weaker than that of FK409. In human washed platelets (WP), FR146801 and FK409 inhibited collagen-induced platelet aggregation in a concentration-dependent manner. The inhibitory effects of FR146801 and FK409 on platelet aggregation were closely reflected by the increase in the intraplatelet cGMP level. This intensely suggests that the antiplatelet activities of FR146801 and FK409 are due to NO-released from them. In the rat extracorporeal shunt model, FR146801 inhibited thrombus formation dose-dependently and its inhibition was significant at 10 mg/kg, p.o. FK409 suppressed thrombus formation significantly at 1.0 mg/kg, p.o., at which it induced significant hypotension, whereas FR146801 did not show any significant hypotensive effect even at 10 mg/kg, p.o. These results suggest that FR146801 has desirable antiplatelet effects both in vitro and in vivo and that its in vivo antiplatelet effect is more selective than its hypotensive effect, while FK409 does not show a selective antiplatelet effect in vivo.

Effect of thromboxane A2 inhibitors on allergic pulmonary inflammation in mice

Thromboxane (Tx)A2 synthase inhibitors and thromboxane prostanoid (TP) receptor antagonists have been developed as anti-asthma drugs. TxA2 may contribute to airflow limitation and bronchial hyperresponsiveness, and these compounds have been demonstrated to improve them. However, it is not known whether TxA2 is involved in bronchial inflammation. To address this question, we explored the influences of OKY-046 (a TxA2 synthase inhibitor) and S-1452 (a TP receptor antagonist) on eosinophilic inflammation of the airways using a murine model. BALB/c mice sensitized with ovalbumin and challenged by repeated exposure to ovalbumin yielded marked eosinophilia in bronchoalveolar lavage fluid (BALF). Treatment with either compound significantly reduced the number of total cells and eosinophils in BALF in a dose-dependent manner. The production of interleukin (IL)-5, IL-2 and interferon (IFN)-gamma by antigen-stimulated splenic mononuclear cells (SMNC) was significantly decreased in mice treated with either compound compared to that in untreated mice. Furthermore, both compounds inhibited proliferation and cytokine production of SMNC in vitro. These results suggest that both OKY-046 and S-1452 are capable of inhibiting production of cytokines, which in turn inhibits eosinophil infiltration into the murine airway. Thus, both thromboxane A2 synthesis inhibitors and thromboxane prostanoid antagonists may be effective as anti-inflammatory drugs in the treatment of asthma.

Revision total knee arthroplasty after failed high tibial osteotomy

Eleven patients (12 knees) who underwent revision total knee arthroplasty after failed high tibial osteotomy are reviewed. All patients were evaluated clinically and radiographically before osteotomy and arthroplasty, and in the follow-up period. The time from osteotomy until arthroplasty ranged from 9 months to 9 years, 6 months (average: 4 years, 5 months). The average follow-up period after arthroplasty was 6 years, 11 months (range: 1 year, 6 months to 13 years). On the basis of the Japan Orthopaedic Association osteoarthritic knee scoring system, the results of total knee arthroplasty after osteotomy were found to be comparable with the results after primary arthroplasty. Patients were divided into two groups according to the time from osteotomy to arthroplasty, alignment of the leg before arthroplasty, and the reason for requiring revision arthroplasty. Group 1 included 6 patients with 6 knees who underwent arthroplasty within 3 years after osteotomy. The main reason for revision arthroplasty in Group 1 was pain due to the recurrence of a varus deformity. Group 2 included 5 patients (6 knees) who underwent revision arthroplasty more than 5 years after osteotomy. The main reason for revision arthroplasty in Group 2 was pain or hydrarthrosis due to the progression to bi-compartmental or tri-compartmental osteoarthritis. There was no significant difference in the clinical results between the two groups. Concerning patellar height, LT/LP of Group 1 was significantly lower than that of Group 2. There were no significant differences in the radiographic findings among the two study groups and the control group of 71 patients (110 knees) who underwent primary total knee arthroplasty, except for alignment before arthroplasty. Using the Japan Orthopaedic Association osteoarthritic knee scoring system, previous osteotomy does not seem to affect the outcome of total knee arthroplasty. With refinement of the technique of high tibial osteotomy, revision total knee arthroplasty after 3 years or less would be avoidable, however, revision total knee arthroplasty due to osteoarthritic deterioration over time would be inevitable.

Differences in the repair process of longitudinal and transverse injuries of cartilage in the rat knee

OBJECTIVE

To clarify the relationship between type or direction of cartilage injury and its repair process, we investigated defects produced in rat knees histologically, immunohistochemically, and histomorphometrically.

METHODS

A full-thickness cartilage injury (1 mm wide and 5 mm long) was produced on the patellar groove of one knee (L-injury) and transversely on the other knee (T-injury) in 42 male Wistar rats. Six rats each were sacrificed at 1, 2, 3, 4, 6 and 8 weeks after surgery, and cartilage tissues were obtained, prepared into 4 microns-thick histologic specimens, and stained with hematoxylin and eosin. Cartilage thickness, cartilage area, and surface roughness were measured using a computer system. Localization of S-100 proteins was evaluated with immunohistochemistry.

RESULTS

Grossly, there were no difference in repair process between L- and T-injuries. However, histological and histomorphometric differences became apparent after the third week: cartilage thickness, repair area, and surface roughness showed better recovery in L-injury than in T-injury. Appearance of S-100-positive protein preceded the appearance of chondrocytes, and L-injury presented S-100 in the entire defect while S-100 in T-injury appeared mainly on the margins of the defect.

CONCLUSIONS

Repair mechanisms of cartilage injury differs according to injury direction. Better repair can be obtained in the injury which is parallel to the direction of joint motion.

Long-term effects of hyaluronan on experimental osteoarthritis in the rabbit knee

OBJECTIVE

Long-term assessment of the effect of hyaluronan (HA) on the articular cartilage and synovium in an animal knee joint during the development of osteoarthritis (OA).

DESIGN

Sixty mature New Zealand white rabbits underwent unilateral anterior cruciate ligament transection (ACLT) and were divided into two groups. Group 1 (SA) received intra-articular injections of 0.3 ml hyaluronan (HA) (i.e., ARTZ, MW: 8 x 10(5)) beginning 4 weeks after ACLT, once a week for 5 weeks. Group 2 (SV) received injections of the vehicle (phosphate buffered saline) in the same fashion as with the SA group. The contralateral nonoperated knee served as control. All animals were killed 21 weeks after surgery and their knee joints evaluated by gross morphologic, histologic, histomorphometric and biochemical analyses.

RESULTS

Gross morphological inspection indicated that the femoral condyles from the knees injected with vehicle suffered more severe cartilage damage than cartilage from the knees injected with HA. Furthermore, two out of three histomorphometric parameters measured in the HA-treated cartilage (i.e., cartilage thickness and cartilage area which were not statistically different than control) provided evidence showing a protective effect of HA on the femoral condyles following ACLT. Biochemical analysis showed articular cartilage remaining on the femoral condyles following ACLT to have similar characteristics to contralateral controls. However, DNA concentration in the synovium from the ACLT knees of the vehicle-treated animals was greater than contralateral control, while this parameter was not statistically different than contralateral control in the HA treated animals.

CONCLUSIONS

These results demonstrate a protective effect of HA on preservation of the articulating surface of the femoral condyle following ACLT up to 21 weeks post-surgery.

Localization of heat shock protein in osteoarthritic cartilage

In osteoarthritic (OA) chondrocytes, expression of 70 kD heat shock protein (HSP70) is enhanced under stress. The HSP70 level is also related to OA severity in humans. In the present study, specimens of OA cartilage were obtained from 14 surgically treated female patients. Their disease severity was evaluated according to Mankin's histological/histochemical grading scores. The ratio of HSP70-positive cells was examined by using immunohistochemistry. As OA became more severe, the ratio of HSP70-positive cells increased in deeper areas from the surface, and there was a positive correlation between the grade and the ratio. Distribution of cells expressing HSP70 mRNA detected by in situ hybridization was similar to the distribution of positive cells in the immunohistochemistry. It was presumed that HSP70 plays a role in cell protection from stress, and that mechanical and biological factors which are related to the enhancement of HSP70 expression, have a considerable influence on OA progressions.

Initial MRI findings of non-traumatic osteonecrosis of the femoral head in renal allograft recipients

Fifty-one renal allograft recipients (15-62 years old, mean: 37 years) were monitored for 2.5-6.5 years (average: 4.3 years) after surgery by using magnetic resonance imaging (MRI) to find (i) initial signs of osteonecrosis of the femoral head (ONF), (ii) the presence of bone marrow edema as an initial sign of ONF, (iii) any changes of MRI patterns, and (iv) the relationship between these MRI findings and prognosis. MRI was performed preoperatively (baseline), and whenever possible during the 6-9th week, 12-16th week, 12th month, and yearly thereafter. T1- and T2-weighted images were obtained by using a spin echo technique. Abnormalities were first detected on MRI of 23 femoral heads in 13 patients between 6 weeks and 12 months. All lesions first showed a low intensity band on T1-weighted images and a high intensity band on T2-weighted images. No symptoms or diffuse patterns, such as bone marrow edema, preceded the appearance of the band pattern. After the 12th month, no new abnormal findings on MRI were detected. The lesions were classified into Type A, B, or C, according to the location. 12 of the 16 Type C femoral head lesions, which extend beyond the medial two thirds of the weight-bearing portion of the acetabulum, became symptomatic 7-14 months after transplantation and then progressed to collapse. Bone marrow edema appeared with radiological collapse and symptoms. With the exception of five lesions in three patients who failed to be MR imaged until 12 months postoperatively, all lesions were first detected on MRI within 16 weeks after transplantation. We therefore postulate that the ischemic event that causes ONF will have occurred within 12 weeks after transplantation, considering the time lag of reparative reaction to the dead bone.

Immunocytochemical distribution of Ca(2+)-independent protein kinase C subtypes (delta, epsilon, and zeta) in regenerating axonal growth cones of rat peripheral nerve

In the peripheral nerve, regenerating axonal sprouts usually emanate at nodes of Ranvier, and extend as growth cones along the inner surface of Schwann cells and/or through Schwann cell columns in the distal nerve segment. In order to elucidate the significance of Ca(2+)-independent protein kinase C in nerve regeneration, localizations of delta, epsilon and zeta subtypes were examined immunocytochemically in sprouts and growth cones of regenerating axons, as well as in normal intact nerves in the rat sciatic nerve. In normal nerves, intense immunoreactivities of delta, epsilon and zeta subtypes were present in axons of both myelinated and unmyelinated fibres. Subcellularly, the distribution of these subtypes in the axoplasm was patchy, and discontinuous in the axolemma and subaxolemmal peripheral zones of myelinated nerves. Some thin myelinated axons showed no immunoreactivity for epsilon subtype. Schwann cells of both myelinated and unmyelinated fibres had moderate immunoreactivities for each subtype. In areas of nerve regeneration, axonal sprouts at nodes of Ranvier, and growth cones extending along Schwann cell basal laminae, had intense immunoreactivities for delta, epsilon and zeta subtypes which are distributed diffusely throughout the axoplasm, and on the entire axolemma. In the sprouts, immunoreactivity for epsilon subtype was strong on the axolemma, but weak or almost absent in the axoplasm. These data, together with those of our previous study, indicate that Ca(2+)-independent protein kinase C subtypes (delta, epsilon and zeta) have basically the same distribution patterns as those of Ca(2+)-dependent subtypes in sprouts and growth cones of regenerating axons, as well as in normal intact axons; albeit epsilon subtype is somewhat different in distribution and intensity from delta and zeta subtypes. It is suggested that Ca(2+)-independent subtypes are involved in maintaining growth cone activities along with the Ca(2+)-dependent subtypes.

Circulating levels of soluble interleukin-6 receptor in patients with bronchial asthma

In the search for markers of airway inflammation, we investigated the role of soluble interleukin-6 receptor (sIL-6R) in patients with bronchial asthma. Serum levels of sIL-6R were measured in 20 patients with stable asthma and in 18 healthy control subjects by means of a sandwich enzyme-linked immunosorbent assay. Such levels were also evaluated during a spontaneous attack of asthma (n = 10) as well as that after allergen inhalation (n = 7). Results were compared with those observed during the stable state and after the inhalation of methacholine. Serum levels of sIL-6R in asthmatic patients (132 +/- 31 ng/ml) significantly exceeded those of control subjects (111 +/- 16 ng/ml) (p < 0.05). These levels showed no correlation with such clinical variables as nonspecific bronchial hyperreactivity, atopic status, or serum concentration of IgE. Serum sIL-6R levels observed during an asthmatic attack versus those during the stable state (4 wk later) differed significantly. After a severe attack of asthma, such levels were significantly elevated on the second and third days, but not on Day 5. After challenge, circulating levels of sIL-6R were significantly increased 24 h after the inhalation of allergen but not of methacholine. Results suggest that serum levels of sIL-6R are increased in patients with asthma and are further increased during a spontaneous attack or that provoked by the inhalation of allergen. Thus, serum sIL-6R may reflect inflammation of the airway. Further studies are indicated to determine the clinical significance and the application of serum levels of sIL-6R in evaluating asthmatic patients.

Detection of interstitial pneumonitis in patients with rheumatoid arthritis by measuring circulating levels of KL-6, a human MUC1 mucin

In rheumatoid arthritis (RA), interstitial-pneumonitis is one of the major extraarticular complications that worsens a patient's prognosis. KL-6, a human MUC1 mucin, has been reported to be a sensitive serum marker for activity of interstitial pneumonitis. We investigated the clinical significance of serum KL-6 level in patients with RA. Serum levels of KL-6 and RA-associated inflammatory markers were evaluated in 177 RA patients. The diagnosis of active interstitial pneumonitis was made by clinical symptoms, pulmonary function tests, chest X-ray film, and high resolution CT. Serum KL-6 was increased in 8 of 9 (88.9%) RA patients with active interstitial pneumonitis but in only 1 of 168 (0.6%) RA patients without active interstitial pneumonitis. No significant correlation was found between KL-6 level and conventional clinical parameters. In RA, abnormal elevation of serum KL-6 strongly indicates the complication of active interstitial pneumonitis.

KL-6, a human MUC1 mucin, is chemotactic for human fibroblasts

KL-6 in serum and bronchoalveolar lavage fluid has been reported to be a sensitive marker indicating the activity of fibrosing lung diseases. The molecule is clustered in MUC1 mucin according to the findings of immunohistochemical and cytometric studies. To elucidate the pathogenic role of KL-6 in fibrosing lung disease, we characterized its biochemical properties and examined whether purified KL-6 is chemotactic for human fibroblasts in vitro using modified Boyden chambers. Biochemical properties of purified KL-6 were similar to those of other MUC1 mucins previously reported. KL-6 promoted the migration of 5 of 5 human lung fibroblasts and 3 of 4 human skin fibroblasts. Checkerboard analysis revealed that KL-6 was chemotactic as well as chemokinetic. Though platelet-derived growth factor, fibroblast growth factor, or fibronectin were also chemotactic for fibroblasts in the experimental system, only fibronectin augmented KL-6-induced chemotaxis. These observations indicate that KL-6 is one of the chemotactic factors for most fibroblasts and that the increased KL-6 in the epithelial lining fluid in small airways may cause the intra-alveolar fibrosis in fibrosing lung diseases.

Switch from conventional to high-flux membrane reduces the risk of carpal tunnel syndrome and mortality of hemodialysis patients

The use of a high-flux membrane, which eliminates larger molecular weight solutes with better biocompatibility, has steadily increased since the discovery of beta-2 microglobulin (beta 2m) amyloidosis in 1985. The long-term effects of a dialyzer membrane on morbidity and mortality are not completely understood. To examine the membrane effect as a factor of carpal tunnel syndrome onset and mortality, multivariate Cox regression analysis with time-dependent covariate was conducted on 819 patients from March 1968 to November 1994 at a single center. Two hundred and forty-eight of the patients were either switched from the conventional to high-flux membrane or treated only with a high-flux membrane. Fifty-one patients underwent a CTS operation and 206 died. Membrane status (on high-flux or on conventional) was considered as time-dependent covariate and risk was adjusted for age, gender, type of renal disease and calendar year of dialysis initiation. The relative risk of CTS was reduced to 0.503 (P < 0.05) and mortality 0.613 (P < 0.05) by dialysis on the high-flux membrane, compared to the conventional membrane. Serial measurements of beta 2m indicated significantly lower beta 2m to persist in patients on the high-flux membrane. The high-flux membrane decreased the risk of morbidity and mortality substantially. Larger molecule elimination was shown important not only for preventing beta 2m amyloidosis, but for prolonging survival of dialysis patients as well.

Comparative studies of circulating KL-6, type III procollagen N-terminal peptide and type IV collagen 7S in patients with interstitial pneumonitis and alveolar pneumonia

KL-6, a MUC1 mucin preferentially expressed in regenerating type 2 pneumocytes, has been reported to be a sensitive serum marker for evaluating the disease activity of interstitial pneumonitis (IP). Type III procollagen N-terminal peptide (PIIIP) and type IV collagen 7S (7S collagen) have also been reported to be useful in the serological evaluation of the activity. Their levels were measured and their serodiagnostic values were compared simultaneously in patients with IP and alveolar pneumonia. The study population was 45 patients with IP and 12 patients with alveolar pneumonia. Serum KL-6 levels were measured by a specific enzyme immunoassay, and both serum PIIIP and 7S collagen concentrations by their correspondent radioimmunoassay kits. There were no significant difference of serum C-reactive protein level, which was evaluated as an indicator of inflammatory process, between IP and alveolar pneumonia patients. In IP, the abnormally elevated rate of KL-6 [80% (36/45)] was significantly higher than those of PIIIP [40% (18/45)] and 7S collagen [40% (18/45)]. In alveolar pneumonia, the rate of KL-6 [0% (0/12)] was significantly lower than those of PIIIP [33% (4/12)] and 7S collagen [25% (3/12)]. There were no significant correlations among serum levels of the markers. These observations indicate that the serodiagnostic value of KL-6 for IP is superior to that of PIIIP and 7S collagen, and that KL-6 has a characteristic to discriminate IP from alveolar pneumonia.

Ploidy analysis in paraffin-embedded malignant fibrous histiocytoma by DNA cytofluorometry and flourescence in situ hybridization

To prove the relationship between chromosomal aberration and DNA ploidy in human malignant fibrous histiocytoma (MFH), fluorescence in situ hybridization (FISH) and DNA cytofluorometry were performed in this study. For FISH study, the nucleus of each tumor cell was isolated from paraffin-embedded tissue of nine MFHs. Five chromosome-specific DNA probes (1p36, 1q12, 8q21.3, 11 centromere, and 17 centromere) were hybridized on cell nuclei. Cells with more than three probe signals were regarded as chromosome polysomy. All of the tumors analyzed by FISH had extra copies. The average percentage of polysomy in all tumors was high, ranging from 10.2% to 49.2%. The DNA ploidy patterns, and the percentage of hyperdiploid cells showing a greater DNA content than diploid cells, were obtained from DNA cytofluorometry. Three of nine were diploid patterns and six were non-diploid patterns, and the percentage of hyperdiploid cells in all tumors was high, ranging from 9.1% to 61.9%. The percentage of polysomy could be correlated with the percentage of hyperdiploid cells in each cell. In this study, we found that the DNA ploidy change was closely correlated with aberrations of chromosome copy number in MFH. In addition, the alterations of specific chromosome copy number could be detected in MFH showing diploid cells. Thus, these data indicate that FISH and DNA cytofluorometry are available as a cytogenetic tool for the analysis of interphase nuclei of bone and soft tissue tumors including MFH.

Analysis of heat shock proteins and cytokines expressed during early stages of osteoarthritis in a mouse model

OBJECTIVE

Osteoarthritis (OA) is a debilitating disease of the joints. The joints of affected individuals are characterized by a progressive degeneration of articular cartilage leading to inflammation and pain. The expression of heat shock proteins (HSPs) is a ubiquitous self-protective mechanism of all cells under stress, furthermore, the synovium of osteoarthritic individuals contains high levels of cytokines. This study seeks to establish the role of HSPs and cytokines in OA.

METHODS

We have investigated the presence of HSPs and cytokines in articular cartilage during early stages of OA in a mouse that is known to develop spontaneous OA lesions (C57 black mouse). The articular cartilage from closely related mice (C57BL/6) was used as control. Messenger RNAs (mRNAs) for HSPs (HSP32, HSP47, HSP60, HSP70, HSP84 and HSP86) and cytokines [interleukin-1 beta (IL-1 beta), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma)] were detected by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

The mRNA levels of HSP47, HSP70, HSP86, IL-6, and IFN-gamma were up-regulated in the cartilage of C57 black mice, whereas, the level of expression of HSP32, HSP60, HSP84 and IL-1 beta remained unchanged. Furthermore, the expression of IL-1 beta, IL-6, TNF-alpha and IFN-gamma mRNA was associated with expression of HSP60, HSP47, HSP70 and HSP70/HSP86 mRNA, respectively.

CONCLUSIONS

The findings in this study suggest that chondrocytes are conditioned under non-physiological stress during early stages of OA, In addition, among HSPs, HSP70 was associated with two different highly expressed cytokines in C57 black mice, indicating the possible role of HSP70 as a characteristic indicator of early stage of OA.

Adenovirus vector-mediated gene transduction to chondrocytes: in vitro evaluation of therapeutic efficacy of transforming growth factor-beta 1 and heat shock protein 70 gene transduction

OBJECTIVE

To investigate the effects of adenovirus vector-mediated gene transduction of E. coli beta-galactosidase (LacZ), transforming growth factor-beta 1 (TGF-beta 1), and heat shock protein 70 (HSP 70) on human chondrocyte-like cell line (HCS-2/8).

METHODS

We examined expression of transduced genes and their expression periods by 5 bromo-4-chloroindolyl-beta-D-galactoside (X-gal) staining. Northern blotting, ELISA, and Western blotting. To assess the influence of TGF-beta 1 and HSP70 gene transduction, the expression of mRNA of type II collagen, proteoglycan core protein, matrix metalloproteinase 3 (MMP3) and tissue inhibitor of matrix metalloproteinase 1 were examined by Northern blotting.

RESULTS

Staining with X-gal indicated that the genes were transduced into a majority of the cells. Expression of the transduced genes in the cells was continued for at least 21 days. Transduction of TGF-beta 1 gene enhanced mRNA expression of type II collagen and proteoglycan core protein, but suppressed MMP3 mRNA expression in the cells. Expression of HSP70 was also high. Enhanced expression of HSP70 elevated mRNA expression of proteoglycan core protein.

CONCLUSION

These results indicate adenovirus vector is useful in chondrocyte gene therapy, and it could be an efficient mediator of TGF-beta 1 and HSP70 gene transduction.

Method of histomorphometric assessment of glycosaminoglycans in articular cartilage

A method of image analysis has been developed for use in the semiquantitative histomorphometric assessment of glycosaminoglycans in articular cartilage stained with safranin O. The reliability of the methodology is reported along with its application to the assessment of articular cartilage in a model of osteoarthritis, i.e., transection of the anterior cruciate ligament in rabbits. With this system, specimens of normal and osteoarthritic articular cartilage were assessed histomorphometrically for the following parameters: total cartilage area, percentage of safranin O stained area, mean gray scale (average stain intensity), and gray scale index (the relative total amount of glycosaminoglycans). Reproducibility was established for 12 specimens of normal cartilage and found to have a SD of less than 8% of the mean for each parameter that was measured. Image analysis of osteoarthritic cartilage revealed each of the parameters, except for average stain intensity, to be significantly lower than that in control cartilage.

Comparison of hemodynamic effects of nitric oxide (NO) donors with different NO-releasing properties in rats

The aim of this study was to compare the hemodynamic effects of three nitric oxide (NO) donors [i.e., (+/-)-(E)-ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409), (+/-)-N-[(E)-4-ethyl-3-[(Z)-hydroxyimino]-6-methyl-5-nitro-3-he ptenyl]-3-pyridinecarboxamide (FR 146801) and isosorbide dinitrate (ISDN)] in rats. In in vitro experiments, FK409 had a higher spontaneous NO-releasing rate in solution and more potent vasorelaxant activity in isolated rat aorta than other drugs. FR146801 and ISDN showed almost the same vasorelaxant activity. In in vivo experiments, FK409 significantly decreased hematocrit at 1.0 mg/kg p.o., whereas FR146801 and ISDN significantly decreased it at 10 mg/kg p.o., suggesting that these NO-donating agents cause significant plasma volume expansion. However, only FK409 showed significant hypotensive effects immediately after oral administration even at 0.32 mg/kg; FR146801 and ISDN did not cause any significant hypotension at 10 mg/kg, suggesting that FK409 induces much more potent arterial vasodilation than other drugs. These findings suggest that NO donors induce significant plasma volume expansion and that the differences in the selectivities between these effects and their hypotensive effects is probably produced by their different NO-releasing activities.

Structure-activity relationships of spontaneous nitric oxide releasers, FK409 and its derivatives

(+/-)-(E)-4-Ethyl-2-[(E)-hydroxyimino]-5-nitro-3-hexenamide (FK409) shows both potent in vitro vasorelaxant and antiplatelet activities via nitric oxide (NO) generated spontaneously from the compound. In this study, we measured spontaneous NO-releasing rates of a series of FK409 derivatives, of which chain lengths or substituents were systematically modified, in sodium-phosphate buffer solution at pH 7.4. Furthermore, we studied their in vitro antiplatelet and vasorelaxant effects to evaluate relationships between spontaneous NO-releasing activities of FK409 analogs and their biological activities. FK409 derivatives were found to possess different spontaneous NO-releasing rates and biological activities according to their structural modification. In addition, these studies revealed a close correlation between NO-releasing rates of FK409 derivatives and their in vitro antiplatelet activities in human platelet-rich plasma, whereas the in vitro vasorelaxant activities of these compounds in isolated rat aorta did not correlate with the rates of NO liberation. The vasorelaxant effects were supposed to be affected by the structural properties of FK409 derivatives as well as their NO-releasing abilities.

Distal acinar emphysema and interstitial pneumonia in a patient with von Recklinghausen's disease: five-year observation following quitting smoking

Cystic lesion, malignancy and interstitial pneumonia are well-known as pulmonary complications of patients with von Recklinghausen's disease. We report herein an unusual patient with distal acinar emphysema and interstitial pneumonia of prominent hypercellularity demonstrated by transbronchial biopsy and broncho-alveolar lavage fluid (BALF). Six months after quitting smoking, the total cell count of BALF was remarkably reduced. This patient remains stable under 5-year observation in terms of symptoms and findings of both BALF and pulmonary function tests. Quitting smoking may have facilitated a favorable prognosis for the particular lung disease complicated in this patient.

Hydrostatic pressure influences mRNA expression of transforming growth factor-beta 1 and heat shock protein 70 in chondrocyte-like cell line

The present study investigated the influence of hydrostatic pressure on the expression of cytokines and heat shock protein 70 in a chondrocyte-like cell line. Chondrocyte-like cells (HCS-2/8) were exposed to hydrostatic pressure by a special pressure apparatus. Total RNA for cytokines (interleukin-1 beta, basic fibroblast growth factor, insulin-like growth factor-I, and transforming growth factor-beta 1) and for heat shock protein 70 was extracted and was analyzed by a polymerase chain reaction method and Northern blotting. An assay for incorporation of [35S]sulfate was performed to assess proteoglycan synthesis. The expression of transforming growth factor-beta 1 mRNA was enhanced after exposure to 5-MPa of hydrostatic pressure and was reduced after 50 MPa, whereas the expression of heat shock protein 70 was enhanced following exposure to 50 MPa of hydrostatic pressure. The incorporation of [35S]sulfate into the cultured cells increased following exposure to 1-5 MPa of hydrostatic pressure and decreased following 10-50 MPa of pressure. These results suggest that hydrostatic pressure at physiologic levels enhances the expression of transforming growth factor-beta 1 mRNA in addition to increasing proteoglycan synthesis in chondrocytes and that excessively high hydrostatic pressure reduces the expression of transforming growth factor-beta 1 mRNA and increases the expression of heat shock protein 70 mRNA while decreasing proteoglycan synthesis.

A study of the normal values and habituation phenomenon of sympathetic skin response

Sympathetic skin response (SSR) has been developed recently as a method of capturing the autonomic nerve response as a parameter of the sweat gland function. In this study, our aim was to obtain the normal values with regard to both amplitude and latency of SSR from 50 healthy subjects and to find out the habituation mode, which is one of the most characteristic phenomena of SSR. The measurements were recorded from the hand and foot by rectangular waveform electric stimulation. The correlation coefficient regarding hand and foot leads, amplitude, and latency were studied at normal values. The result was that no significant difference could be observed between the left and right leads with regard to amplitude and latency recorded from the hand and foot leads. However, between hand and foot leads, a significant difference was observed for both latency and amplitude. As for the habituation, electric stimulations were also applied to 20 healthy subjects (age range, 21-62 yr) in the same manner as that used in taking the normal values. For the latency and amplitude of the response in association with the stimulation trials (Rn), the mean values of the hand as well as the foot were determined by averaging the values recorded from both hands and both feet of the 20 subjects. These values were designated as the latency and the amplitude of the hand and foot from R1 to R15. The changes observed in response to the transition in the number of stimulations were statistically evaluated as a gradual decrease in the amplitude. This phenomenon is thought to be a result of learning. On the basis of the 15 consecutive stimulations, a decrease in amplitude to the 7th and 8th stimulations and constancy in the results thereafter was observed, although minor differences in the results were apparent between the hand and foot leads.

Epidural hematoma of the lumbar spine, simulating extruded lumbar disk herniation: clinical, discographic, and enhanced magnetic resonance imaging features. A case report

STUDY DESIGN

This case report describes a patient with epidural hematoma of the lumbar spine and progressive intermittent claudication whose imaging findings were similar to those of a patient with extruded disk herniation.

OBJECTIVES

To highlight the diagnosis and cause of the lumbar epidural hematoma.

SUMMARY OF BACKGROUND DATA

The characteristics of imaging of lumbar epidural hematomas have been reported. To the authors' knowledge, a case of epidural hematoma with leakage of the contrast medium into the mass at discogram has never been reported.

METHODS

A case of a lumbar epidural hematoma with 10-15 minutes of intermittent claudication was described. There was no history of major trauma or coagulation disorders. Diagnosis was made using magnetic resonance imaging, myelography, discography, and computed tomography. The magnetic resonance image demonstrated a relatively large, rounded mass posterior to the S1 vertebral body with L5-S1 disc protrusion. A gadolinium-enhanced magnetic resonance image showed a rim-enhancing lesion. A discogram revealed leakage of the contrast medium into the mass. The mass was diagnosed as extruded disk herniation, and surgery was performed.

RESULTS

At surgery no evidence of obvious disk herniation was detected, but the encapsulated hematoma was found.

CONCLUSIONS

A case of chronic lumbar epidural hematoma in which clinical and imaging findings were similar to those of an extruded lumbar disk herniation was reported. Clinical information and results of imaging studies should be analyzed carefully because the imaging findings of contained epidural hematomas are often quite specific to this condition and can be differentiated from those of extruded disc herniations. Management of chronic lumbar epidural hematoma may be altered by a specific diagnosis.