Long-term prognosis of late spontaneous reperfusion after failed thrombolysis for acute myocardial infarction

BACKGROUND

Early reperfusion improves left ventricular (LV) function and survival after acute myocardial infarction (MI). Thrombolytic therapy achieves early patency of the infarct artery in about two-thirds of patients. In nearly half of the remaining patients, in whom early reperfusion was not achieved with thrombolytic therapy, the infarct artery might reopen by the time of predischarge angiography. However, the impact of such late spontaneous reperfusion after failed thrombolytic therapy on LV function and long-term survival remained unclear.

HYPOTHESIS

This study was undertaken to assess implication of late spontaneous reperfusion after failed thrombolytic therapy on LV function and long-term survival after acute MI.

METHODS

The study consisted of 198 patients with anterior acute MI who underwent thrombolytic therapy and predischarge angiography: 160 patients with infarct artery patent early and late after therapy (persistent patency), 17 patients with infarct artery occluded early after therapy but patent at predischarge angiography (late spontaneous reperfusion), and 21 patients with infarct artery occluded early and late after therapy (persistent occlusion).

RESULTS

Persistent patency was associated with enhanced improvement in LV ejection fraction (7.7 +/- 11.8%) compared with late spontaneous reperfusion (0.0 +/- 9.6%, p = 0.03) and persistent occlusion (-1.4 +/- 9.7%, p = 0.003). Persistent patency was associated with better long-term survival than with late spontaneous reperfusion (p < 0.001) and persistent occlusion (p < 0.001). Multivariate analysis comparing persistent patency and late spontaneous reperfusion showed that early reperfusion was an independent predictor of long-term survival.

CONCLUSION

Late spontaneous reperfusion after failed thrombolytic therapy was associated with poor LV function and long-term survival, emphasizing the importance of early reperfusion.

Development and characteristics of pannus-like soft tissue in osteoarthritic articular surface in rat osteoarthritis model

OBJECTIVES

Pannus is invasive granulation tissue found on the articular cartilage having rheumatoid arthritis (RA). However, pannus-like tissue has also been found in osteoarthritis (OA). Our previous study showed that pannus-like tissue in OA (OA pannus) was frequently found in human OA samples. The purpose of the study is to investigate the development and the characteristics of OA pannus in a rat OA model.

DESIGN

Ligaments of the knee joint were transected in Wister rats to induce OA. The knee joints were removed at weeks 1, 2, 4 and 6, and subjected to histological study. Samples were stained with hematoxylin and eosin (HE), Safranin-O and immuno-stained for vimentin, CD34, type II collagen and MMP-3. The whole knee joint of OA rats was implanted in SCID mice and kept for a further 3 weeks. Then the histological findings were evaluated in HE sections.

RESULT

OA pannus appeared at week 2 and extend over the articular surface. OA pannus cells were positive for vimentin and/or CD34. At week 6, a part of articular surface was restored with matrix. OA pannus cells expressed MMP-3 as well as type II collagen. Histological study of rat OA knees implanted in SCID mice showed that OA pannus cells filled the joint space and invaded articular cartilage.

CONCLUSIONS

The presence of OA pannus was found in a rat OA model and its features were similar to those in human OA. OA pannus had both catabolic and reparative features, and the latter feature were speculated to be dominant in the later phase of the disease under a certain environmental condition.

Tryptase enhances release of vascular endothelial growth factor from human osteoarthritic chondrocytes

OBJECTIVE

A contribution of mast cells and its mediators in the pathogenesis of arthritis has been postulated. We aimed to clarify the role of mast cell-derived serine protease tryptase and proteinase activated receptor (PAR)-2-mediated signaling in chondrocytes.

METHODS

Human articular cartilage specimens were obtained from patients with osteoarthritis (OA), rheumatoid arthritis (RA) and with traumatic fracture without arthritis (PT; as controls) who underwent joint surgery. Isolated chondrocytes were cultured in vitro by monolayer, and confluent cells were incubated with recombinant human lung Beta tryptase or with a PAR-2 agonist peptide. The secreted level of vascular endothelial growth factor (VEGF) in culture supernatant was measured using commercially available ELISA kits, and expression of VEGF mRNA was analyzed using real-time PCR.

RESULTS

The tryptase-stimulated chondrocytes from OA or RA, but not from PT patients, produced significantly higher amount of VEGF in their supernatants. The response was blocked by a G-protein receptor inhibitor pertussis toxin, however, was not reproduced by incubation of cells with the PAR-2 agonist, suggesting a presence of non-PAR-2 dependent signals for the VEGF induction. In addition, actinomycin D and cycloheximide did not exert significant inhibition, indicating a regulation of VEGF release by tryptase.

CONCLUSION

The inflammatory mediator, mast cell-derived protease tryptase may modulate chondrocyte metabolism through induction of VEGF release.

Positron emission tomography with 18F-FDG in osteoarthritic knee

OBJECTIVES

To evaluate osteoarthritis (OA) of the knee using positron emission tomography (PET) with 2-(18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) as a tracer.

MATERIALS AND METHODS

Fifteen patients with medial-type knee OA and three healthy subjects were enrolled in the study. After clinical examination and conventional radiography, (18)F-FDG PET and magnetic resonance imaging (MRI) were performed. (18)F-FDG uptake was quantified as a standardized uptake value (SUV) and the localization of (18)F-FDG uptake was identified using fusion images created with MRI scans.

RESULTS

(18)F-FDG generally accumulated in periarticular lesions and was absent in the articular cartilage. SUVs of the whole knee were higher in OA than in controls, and those in the medial condyle were higher than in the lateral condyle in OA. Prominent (18)F-FDG uptake was found in the intercondylar notch in OA and extended along the posterior cruciate ligament (PCL) in some cases. Periosteophytic accumulation was found in one-half of cases with definite osteophytes. Accumulation was also found in subchondral lesions and bone marrow, which corresponded with bone edema diagnosed by MRI. No significant correlation was found between SUV and clinical manifestations.

CONCLUSIONS

(18)F-FDG uptake was upregulated in OA and generally accumulated in periarticular lesions. Increased uptake was found in the intercondylar notch extending along the PCL, periosteophytic lesions, and bone marrow. These results provide in vivo pathognomonic insights into OA.

Surgical resection of solitary adrenal metastasis from esophageal carcinoma following esophagectomy

The prognosis of esophageal carcinoma following esophagectomy is poor due to a high frequency of metastasis to periesophageal lymph nodes and distant organs. However, we experienced a case with good prognosis following resection of a solitary adrenal metastatic tumor. The patient was a 70-year-old man diagnosed with type 2 esophageal cancer (Lt-Ae, T2N1M0, Stage IIB) who was treated with esophagectomy. Eight months following surgery, solitary adrenal metastasis was detected by CT, and was resected. At 42 months follow-up he has had a good quality of life in the community without evidence of recurrence. To the best of our knowledge, only five cases with resected solitary adrenal metastases including our case, have been reported, and show a greater than 1-year survival. Consequently, we suggest that resection of solitary organ metastases is a good alternative, even following esophagectomy.

Effects of celecoxib on human chondrocytes--enhanced production of chemokines

OBJECTIVE

The purpose of this study was to examine the effects of a selective cyclooxigenase-2 (COX-2) inhibitor (celecoxib) comparing diclofenac.

METHODS

Using chondrocytes derived from cartilage of non-arthritic (NA) subjects or patients with osteoarthritis (OA) or rheumatoid arthritis (RA), we examined the effects of celecoxib on incorporation of 3H-thymidine and 35S-sulfate, apoptosis, and production of matrix metalloproteinase (MMP)-1, MMP-3, MMP-13, and regulated upon activation, normal T cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1a and nitric oxide (NO).

RESULTS

Celecoxib and diclofenac tended to reduce 3H-tymidine incorporation of chondrocytes. Celecoxib induced apoptosis in a dose-dependent manner, but to a lesser degree than diclofenac. Celecoxib inhibited proteoglycan synthesis (indicated by 35S-sulfate incorporation) in NA chondrocytes, but not in OA and RA chondrocytes. Celecoxib increased interleukin-1 (IL-1)-induced production of RANTES and MIP-1alpha by chondrocytes and decreased IL-1-induced NO production by chondrocytes, whereas it did not affect MMP production.

CONCLUSION

Celecoxib had both beneficial and adverse effects on chondrocytes. RA, OA and NA chondrocytes showed different responses. Interestingly, celecoxib enhanced the production of chemokines.

Expression of proteinase-activated receptors (PAR)-2 in articular chondrocytes is modulated by IL-1beta, TNF-alpha and TGF-beta

OBJECTIVE

To investigate the modulation of expression of proteinase-activated receptor-2 (PAR-2) in articular chondrocytes by inflammatory cytokines.

DESIGN

Articular synovium and cartilage tissues were collected from eight patients with osteoarthritis (OA), and three patients without arthropathy ("normal"). Chondrocytes were stimulated with interleukin (IL)-1beta, tumor necrosis factor (TNF)-alpha or transforming growth factor (TGF)-beta1. The expression of PAR-2 was detected using reverse transcriptase-polymerase chain reaction (PCR), Western blotting and immunofluorescence. Quantitative PCR was performed to assess the expression levels of PAR-2 messenger RNA (mRNA).

RESULTS

The expression of PAR-2 mRNA was demonstrated in both OA and normal chondrocytes as well as in synovial fibroblasts. However, the level of PAR-2 in OA chondrocytes was much higher than in normal chondrocytes. Long-term culture revealed that PAR-2 mRNA expression was maintained up to three passages in OA but not in normal chondrocytes. IL-1beta and TNF-alpha both upregulated PAR-2 expression in normal and OA chondrocytes. In contrast, TGF-beta1 significantly decreased expression of PAR-2 in OA chondrocytes but increased PAR-2 in normal chondrocytes.

CONCLUSIONS

Overexpression of PAR-2 in OA chondrocytes is upregulated by proinflammatory cytokines IL-1beta and TNF-alpha, and down-regulated by regulatory cytokine TGF-beta1. PAR-2 may be involved in the pathogenesis of OA.

Staphylococcal scalded skin syndrome I. Purification of exfoliatin and maternal transmission of neutralizing ability against exfoliatin

Exfoliatin, an exotoxin produced by phage group 2 staphylococci, was separated and was analyzed. The toxin was separated in a single peak by Sephadex G-100 gel filtration and subsequent DEAE Sephadex chromatography. By acrylamide gel disc electrophoresis this single peak was found to contain 2 components both of which posessed exfoliative activity and the same antigenic properties. Their molecular weight, however, differed; the major component had a molecular weight of 30,000 and the minor component had 27,000. The toxin was stable when heated at 60 degrees C for 40 minutes, and labile at 100 degrees C for 20 minutes. The toxin was immunogenic to mice and produced antibody which could be transmitted to neonatal mice to neutralize exfoliative activity of the toxin. Innoculation of the bacteria caused the production of antibodies against both exfoliatin and alpha-hemolysin in mice. The antibodies were also transmitted to neonatal mice to neutralize the exfoliative activity of exfoliatin.

The role of subchondral bone resorption pits in osteoarthritis: MMP production by cells derived from bone marrow

OBJECTIVE

The vascular invasion of bone marrow tissue into the subchondral plate is often observed in articular cartilage and we named it the subchondral bone absorption pit; however, its implication in the pathogenesis of osteoarthritis (OA) has been poorly understood. The purpose of this study was to evaluate its characteristics and roles in osteoarthritic conditions.

METHODS

Articular cartilage specimens from 11 patients with medial type knee OA and 7 non-arthritic cadavers were analyzed with HE staining. OA sections were stained with safranin-O, TRAP (tartrate resistant acid phosphatase) and immunostained with anti-MMP-1, MMP-3, MMP-13, vitronectin receptor (VNR)-alpha chain, vimentin and bone morphogenic protein (BMP) 2/4 antibodies.

RESULTS

Subchondral bone resorption pits were classified according to the extent of invasion: pits with bone marrow tissue were located within uncalcified cartilage below the tidemark in grade I and invaded beyond the tidemark in grade II, while no invasion was seen in grade 0. Grade II pits were dominant in OA compared to non-arthritic joints, especially medial condyles. Proteoglycan detected with safranin-O staining was lost around the tip of grade II pits and the density of pits was related to the modified Mankin Score. Cells in pits expressed vimentin, MMP-1, MMP-3 and MMP-13. Some polynuclear cells co-expressed VNR-alpha chain and MMP-13, whereas pits showed reparative features expressing BMP.

CONCLUSION

These results suggest that subchondral bone resorption pits contribute to cartilage degradation by expressing matrix metalloproteinases in OA.

Implication of interleukin 18 in production of matrix metalloproteinases in articular chondrocytes in arthritis: direct effect on chondrocytes may not be pivotal

OBJECTIVE

To clarify the effect of interleukin (IL) 18 on cartilage degeneration by studying the profile of IL18 receptor (IL18R) on chondrocytes and the direct effect of IL18 on production of matrix metalloproteinases (MMPs), aggrecanases, and tissue inhibitors of metalloproteinases (TIMPs) in articular chondrocytes.

METHODS

Monolayer cultured human articular chondrocytes were isolated from non-arthritic subjects and patients with rheumatoid arthritis or osteoarthritis. Gene expression of IL18, IL18Ralpha, IL18Rbeta, MMPs, and aggrecanases was detected by RT-PCR. Protein levels of IL18Ralpha were analysed by flow cytometry. Protein levels of IL18, MMPs, and TIMPs were measured by ELISA. Aggrecanase-2 mRNA expression was quantitatively analysed by real time RT-PCR. Protein levels of signalling molecules were assayed by western blotting.

RESULTS

IL18 mRNA was constitutively expressed in chondrocytes, and was enhanced by IL1beta stimulation. Flow cytometric analysis showed that IL1beta, tumour necrosis factor alpha, and IL18 up regulated IL18Ralpha expression levels. The level of IL18Rbeta mRNA was much lower than that of IL18Ralpha, and was slightly up regulated by IL1beta. In chondrocytes responding to IL18, IL18 (1-100 ng/ml) slightly increased the production of MMP-1, MMP-3, and MMP-13, which was blocked by NF-kappaB inhibitor and p38 mitogen activated protein kinase inhibitor. IL18 up regulated mRNA expression of aggrecanase-2, but not aggrecanase-1. IL18 also slightly stimulated TIMP-1 production?through extracellular signal regulated kinase activation.

CONCLUSION

IL18 induces production of MMPs from chondrocytes in inflammatory arthritis. Although the direct effect of IL18 on chondrocytes may not be pivotal for the induction of cartilage degeneration, IL18 seems to play some part in the degradation of articular cartilage in arthritis.

Plasminogen activator inhibitor-1 is elevated, but not essential, in the development of bleomycin-induced murine scleroderma

Accumulative data have demonstrated that plasminogen activator inhibitor-1 (PAI-1) plays an important role in the extracellular matrix metabolism; however, the involvement of PAI-1 in scleroderma has not been fully elucidated. In this study, we investigated the role of PAI-1 in bleomycin-induced murine scleroderma. 100 microg of bleomycin was injected subcutaneously to the back skin of C3H/HeJ mice on alternate day for 4 weeks. Histopathological findings revealed that PAI-1 was positive in macrophage-like cells and fibroblastic cells in the dermis, in parallel with the induction of dermal sclerosis. PAI-1 mRNA expression in the whole skin was up-regulated at 1 and 4 weeks. The production of active PAI-1 protein in the lesional skin was significantly increased 3 and 4 weeks after bleomycin treatment. Next, we examined whether dermal sclerosis is induced by bleomycin in PAI-1-deficient (PAI-1-/-) mice. 10 microg of bleomycin was subcutaneously injected to PAI-1-/- and wild type (WT) mice 5 days per week for 4 weeks. Histological examination revealed that dermal sclerosis was similarly induced even in PAI-1-/- as well as WT mice. Dermal thickness and collagen contents in the skin were significantly increased by bleomycin injection in both PAI-1-/- and WT mice, and the rate of increase was similar. These data suggest that PAI-1 plays an important role, possibly via TGF-beta pathway activation. However, the fact that PAI-1 deficiency did not ameliorate skin sclerosis suggest that PAI-1 is not the essential factor in the development of bleomycin-induced scleroderma, and more complex biochemical effects other than PA/plasmin system are greatly suspected.

In vivo transfection of a cis element 'decoy' against signal transducers and activators of transcription 6 (STAT6)-binding site ameliorates IgE-mediated late-phase reaction in an atopic dermatitis mouse model

Signal transducers and activators of transcription 6 (STAT6) play a crucial role in the transactivation of IL-4 and IL-13, which might be involved in the pathogenesis of atopic dermatitis (AD). We herein reported that the IgE-mediated late-phase reaction significantly decreased in STAT6-deficient (STAT6(-/-)) mice in AD model mice induced by intravenous injection of monoclonal anti-dinitrophenyl (DNP)-IgE antibody and subsequent skin testing with dinitrofluorobenzene. We therefore hypothesized that synthetic double-stranded DNA with a high affinity for STAT6 could be introduced in vivo as decoy cis elements to bind the transcriptional factor and block the gene activation contributing to the onset and progression of AD, thus providing effective therapy for AD. Treatment by the transfection of STAT6 decoy oligodeoxynucleotides (ODNs), but not scramble decoy ODN after sensitization by anti-DNP-IgE antibody, had a significant inhibitory effect on not only STAT6 binding to nuclei but also on the late-phase response. A histological analysis revealed that both edema and the infiltration of neutrophils and eosinophils significantly decreased in STAT6 decoy ODN-transfected mice. To examine the mechanism of the in vivo effect of STAT6 decoy ODN, we employed an in vitro mast cells culture system. After IgE receptor engagement, mast cells transfected by STAT6 decoy ODN exhibited normal histamine release, but their cytokine release (TNF-alpha, IL-6) markedly decreased. We herein report the first successful in vivo transfer of STAT6 decoy ODN to reduce the late-phase reaction, thereby providing a new therapeutic strategy for AD.

In vivo transfection of a cis element 'decoy' against signal transducers and activators of the transcription 6 (STAT6) binding site ameliorates the response of contact hypersensitivity

We herein demonstrate that STAT6 plays an important role in the induction of not only acute contact hypersensitivity (CHS), but also chronic CHS in a mouse model using STAT6-deficient (STAT6(-/-)) mice. We, therefore, determine whether synthetic double-stranded DNA with a high affinity for STAT6 can be introduced in vivo as a decoy cis element to bind the transcriptional factor and block the induction of not only acute CHS but also chronic CHS. Treatment by the transfection of STAT6 decoy oligodeoxynucleotides (ODN), after the induction of 2,4,6-trinitrochlorobenzene or other haptens had a significant inhibitory effect on the induction of both acute CHS and chronic CHS. We thus examined the mechanism of the in vivo effect of the transfection of STAT6 decoy ODN in both acute and chronic CHS. In the histological analysis, the infiltration of eosinophils and degranulated mast cells, and the production of IL-4, IL-6 and eotaxin, but not IFN-gamma in the extracts from challenged skin significantly decreased by the transfection of STAT6 decoy ODN. We herein report the first successful in vivo transfer of STAT6 decoy ODN to inhibit acute and chronic CHS, thus providing a new therapeutic strategy not only for the treatment of CHS but also for atopic dermatitis.