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Background/Aims@#Bleeding events after percutaneous coronary intervention (PCI) have important prognostic implications. Data on the influence of an abnormal ankle-brachial index (ABI) on both ischemic and bleeding events in patients undergoing PCI are limited. @*Methods@#We included patients who underwent PCI with available ABI data (abnormal ABI, ≤ 0.9 or > 1.4). The primary endpoint was the composite of all-cause death, myocardial infarction (MI), stroke, and major bleeding. @*Results@#Among 4,747 patients, an abnormal ABI was observed in 610 patients (12.9%). During follow-up (median, 31 months), the 5-year cumulative incidence of adverse clinical events was higher in the abnormal ABI group than in the normal ABI group: primary endpoint (36.0% vs. 14.5%, log-rank test, p < 0.001); all-cause death (19.4% vs. 5.1%, log-rank test, p < 0.001); MI (6.3% vs. 4.1%, log-rank test, p = 0.013); stroke (6.2% vs. 2.7%, log-rank test, p = 0.001); and major bleeding (8.9% vs. 3.7%, log-rank test, p < 0.001). An abnormal ABI was an independent risk factor for all-cause death (hazard ratio [HR], 3.05; p < 0.001), stroke (HR, 1.79; p = 0.042), and major bleeding (HR, 1.61; p = 0.034). @*Conclusions@#An abnormal ABI is a risk factor for both ischemic and bleeding events after PCI. Our study findings may be helpful in determining the optimal method for secondary prevention after PCI.
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Background@#There are no data on comparison between clopidogrel monotherapy and prolonged dual antiplatelet therapy (DAPT) in patients at high-risk undergoing percutaneous coronary intervention (PCI). @*Methods@#Of 2,082 consecutive patients undergoing PCI using second-generation drugeluting stent (DES), we studied 637 patients at high-risk either angiographically or clinically who received clopidogrel longer than 24 months and were event-free at 12 months after index PCI. Patients were divided into 2 groups: the clopidogrel monotherapy group and the prolonged DAPT group. The primary outcome was a composite of all-cause death, non-fatal myocardial infarction (MI), definite or probable stent thrombosis, or stroke between 12 months and 36 months after the index PCI. @*Results@#In propensity score-matched population (246 pairs), the cumulative rate of primary outcome was 4.5% in the clopidogrel monotherapy group and 4.9% in the prolonged DAPT group (hazard ratio, 1.21; 95% confidence interval, 0.54–2.75; P = 0.643). There was no significant difference in all-cause death, MI, stent thrombosis, stroke between the clopidogrel monotherapy group and the prolonged DAPT group. @*Conclusion@#Compared with prolonged DAPT, clopidogrel monotherapy showed similar long-term outcomes in patients at high-risk after second-generation DES implantation.
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Background@#There are no data on comparison between clopidogrel monotherapy and prolonged dual antiplatelet therapy (DAPT) in patients at high-risk undergoing percutaneous coronary intervention (PCI). @*Methods@#Of 2,082 consecutive patients undergoing PCI using second-generation drugeluting stent (DES), we studied 637 patients at high-risk either angiographically or clinically who received clopidogrel longer than 24 months and were event-free at 12 months after index PCI. Patients were divided into 2 groups: the clopidogrel monotherapy group and the prolonged DAPT group. The primary outcome was a composite of all-cause death, non-fatal myocardial infarction (MI), definite or probable stent thrombosis, or stroke between 12 months and 36 months after the index PCI. @*Results@#In propensity score-matched population (246 pairs), the cumulative rate of primary outcome was 4.5% in the clopidogrel monotherapy group and 4.9% in the prolonged DAPT group (hazard ratio, 1.21; 95% confidence interval, 0.54–2.75; P = 0.643). There was no significant difference in all-cause death, MI, stent thrombosis, stroke between the clopidogrel monotherapy group and the prolonged DAPT group. @*Conclusion@#Compared with prolonged DAPT, clopidogrel monotherapy showed similar long-term outcomes in patients at high-risk after second-generation DES implantation.
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BACKGROUND AND OBJECTIVES@#After the first acute myocardial infarction (AMI), a considerable proportion of patients are newly diagnosed with diabetes mellitus (DM). However, in AMI, controversy remains regarding the disparity in prognosis between previously diagnosed DM (known-DM) and newly diagnosed DM (new-DM).@*METHODS@#The study included 10,455 patients with AMI (non-DM, 6,236; new-DM, 659; known-DM, 3,560) admitted to one of 15 participating centers in Korea between November 2011 and January 2016 (average follow-up, 523 days). We compared the characteristics and clinical course of patients with known-DM and those with new- or non-DM.@*RESULTS@#Compared to patients with known-DM, those with new-DM or non-DM were younger, more likely to be male, and less likely to have hypertension, dyslipidemia, prior stroke, angina, or myocardial infarction. Compared to patients with new-DM or non-DM (reference), those with known-DM had higher risks of major adverse cardiac events (hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.06–1.35; p=0.004), cardiac death (HR, 1.26; 95% CI, 1.01–1.57; p=0.042), and congestive heart failure (HR, 1.58; 95% CI, 1.20–2.08). Unlike known-DM, new-DM did not increase the risk of cardiac events (including death).@*CONCLUSIONS@#Known-DM was associated with a significantly higher risk of cardiovascular events after AMI, while new-DM had a similar risk of cardiac events as that noted for non-DM. There were different cardiovascular outcomes according to diabetes status in patients with AMI.
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BACKGROUND AND OBJECTIVES: After the first acute myocardial infarction (AMI), a considerable proportion of patients are newly diagnosed with diabetes mellitus (DM). However, in AMI, controversy remains regarding the disparity in prognosis between previously diagnosed DM (known-DM) and newly diagnosed DM (new-DM). METHODS: The study included 10,455 patients with AMI (non-DM, 6,236; new-DM, 659; known-DM, 3,560) admitted to one of 15 participating centers in Korea between November 2011 and January 2016 (average follow-up, 523 days). We compared the characteristics and clinical course of patients with known-DM and those with new- or non-DM. RESULTS: Compared to patients with known-DM, those with new-DM or non-DM were younger, more likely to be male, and less likely to have hypertension, dyslipidemia, prior stroke, angina, or myocardial infarction. Compared to patients with new-DM or non-DM (reference), those with known-DM had higher risks of major adverse cardiac events (hazard ratio [HR], 1.20; 95% confidence interval [CI], 1.06–1.35; p=0.004), cardiac death (HR, 1.26; 95% CI, 1.01–1.57; p=0.042), and congestive heart failure (HR, 1.58; 95% CI, 1.20–2.08). Unlike known-DM, new-DM did not increase the risk of cardiac events (including death). CONCLUSIONS: Known-DM was associated with a significantly higher risk of cardiovascular events after AMI, while new-DM had a similar risk of cardiac events as that noted for non-DM. There were different cardiovascular outcomes according to diabetes status in patients with AMI.
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Humains , Mâle , Mort , Diabète , Dyslipidémies , Études de suivi , Défaillance cardiaque , Hypertension artérielle , Corée , Infarctus du myocarde , Pronostic , Accident vasculaire cérébralRÉSUMÉ
BACKGROUND/AIMS: Although a low triiodothyronine (T3) state is closely associated with heart failure (HF), it is uncertain whether total T3 levels on admission is correlated with the clinical outcomes of acute myocardial infarction (AMI). The aim of this study is to investigate the prognostic value of total T3 levels for major adverse cardiovascular and cerebrovascular events (MACCEs) in patients with AMI undergone percutaneous coronary intervention (PCI). METHODS: A total of 765 PCI-treated AMI patients (65.4 ± 12.6 years old, 215 women) between January 2012 and July 2014 were included and 1-year MACCEs were analyzed. We assessed the correlation of total T3 and free thyroxine (fT4) with prevalence of 1-year MACCEs and the predictive values of total T3, fT4, and the ratio of total T3 to fT4 (T3/fT4), especially for HF requiring re-hospitalization. RESULTS: Thirty patients (3.9%) were re-hospitalized within 12 months to control HF symptoms. Total T3 levels were lower in the HF group than in the non-HF group (84.32 ± 21.04 ng/dL vs. 101.20 ± 20.30 ng/dL, p < 0.001). Receiver operating characteristic curve analysis showed the cut-offs of total T3 levels (≤ 85 ng/dL) and T3/fT4 (≤ 60) for HF (area under curve [AUC] = 0.734, p < 0.001; AUC = 0.774, p < 0.001, respectively). In multivariate analysis, lower T3/fT4 was an independent predictor for 1-year HF in PCI-treated AMI patients (odds ratio, 1.035; 95% confidential interval, 1.007 to 1.064; p = 0.015). CONCLUSIONS: Lower levels of total T3 were well correlated with 1-year HF in PCI-treated AMI patients. The T3/fT4 levels can be an additional marker to predict HF.
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Humains , Aire sous la courbe , Défaillance cardiaque , Coeur , Analyse multifactorielle , Infarctus du myocarde , Intervention coronarienne percutanée , Prévalence , Pronostic , Courbe ROC , Thyroxine , Tri-iodothyronineRÉSUMÉ
BACKGROUND AND OBJECTIVES: Combination antiplatelet therapy reduces the risk of ischemic stroke compared with aspirin monotherapy in non-valvular atrial fibrillation (NVAF) patients. The underlying mechanism, however, remains unclear. In addition, the association between platelet inhibition and thrombogenicity in NVAF has not been evaluated. SUBJECTS AND METHODS: We randomized 60 patients with NVAF that were taking 100 mg of aspirin daily (>1 month) to adding 75 mg of clopidogrel daily (CLPD group), 100 mg of cilostazol twice daily (CILO group), or 1000 mg of omega-3 polyunsaturated fatty acid twice daily (PUFA group). Biomarkers (von Willebrand factor antigen [vWF:Ag], fibrinogen, D-dimer, and high-sensitivity C-reactive protein [hs-CRP]) and platelet reactivity (PR), which were the levels stimulated by adenosine diphosphate (ADP), thrombin-receptor agonist peptide, collagen, and arachidonic acid, were measured at baseline and 30-day follow-up. RESULTS: Combination antiplatelet therapy significantly reduced vWF:Ag and fibrinogen levels (7.7 IU/dL, p=0.015 and 15.7 mg/dL, p=0.005, respectively), but no changes were found in D-dimer and hs-CRP levels. The CLPD and CILO groups showed fibrinogen and vWF:Ag level reductions (24.9 mg/dL, p=0.015 and 9.3 IU/dL, p=0.044, respectively), whereas the PUFA group did not show any differences in biomarkers. Irrespective of regimen, the changes in fibrinogen and vWF:Ag levels were mainly associated with the change in ADP-mediated PR (r=0.339, p=0.008 and r=0.322, p=0.012, respectively). CONCLUSION: In patients with NVAF, combination antiplatelet therapy showed reductions for vWF:Ag and fibrinogen levels, which may be associated with the inhibitory levels of ADP-mediated PR. The clinical implications of these findings need to be evaluated in future trials.
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Humains , ADP , Acide arachidonique , Acide acétylsalicylique , Fibrillation auriculaire , Marqueurs biologiques , Plaquettes , Protéine C-réactive , Collagène , Fibrinogène , Études de suivi , Antiagrégants plaquettaires , Accident vasculaire cérébralRÉSUMÉ
BACKGROUND/AIMS: This study is a head-to-head comparison of predictive values for long-term cardiovascular outcomes between exercise electrocardiography (ex-ECG) and computed tomography coronary angiography (CTCA) in patients with chest pain. METHODS: Four hundred and forty-two patients (mean age, 56.1 years; men, 61.3%) who underwent both ex-ECG and CTCA for evaluation of chest pain were included. For ex-ECG parameters, the patients were classified according to negative or positive results, and Duke treadmill score (DTS). Coronary artery calcium score (CACS), presence of plaque, and coronary artery stenosis were evaluated as CTCA parameters. Cardiovascular events for prognostic evaluation were defined as unstable angina, acute myocardial infarction, revascularization, heart failure, and cardiac death. RESULTS: The mean follow-up duration was 2.8 ± 1.1 years. Fifteen patients experienced cardiovascular events. Based on pretest probability, the low- and intermediate-risks of coronary artery disease were 94.6%. Odds ratio of CACS > 40, presence of plaque, coronary stenosis ≥ 50% and DTS ≤ 4 were significant (3.79, p = 0.012; 9.54, p = 0.030; 6.99, p < 0.001; and 4.58, p = 0.008, respectively). In the Cox regression model, coronary stenosis ≥ 50% (hazard ratio, 7.426; 95% confidence interval, 2.685 to 20.525) was only significant. After adding DTS ≤ 4 to coronary stenosis ≥ 50%, the integrated discrimination improvement and net reclassification improvement analyses did not show significant. CONCLUSIONS: CTCA was better than ex-ECG in terms of predicting long-term outcomes in low- to intermediate-risk populations. The predictive value of the combination of CTCA and ex-ECG was not superior to that of CTCA alone.
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Humains , Mâle , Angor instable , Calcium , Douleur thoracique , Coronarographie , Maladie des artères coronaires , Sténose coronarienne , Vaisseaux coronaires , Mort , 4252 , Électrocardiographie , Études de suivi , Défaillance cardiaque , Infarctus du myocarde , Odds ratio , PronosticRÉSUMÉ
BACKGROUND/AIMS: Increased arterial stiffness is a well-known risk factor for cardiovascular disease. Cilostazol, a phosphodiesterase type 3 inhibitor, is a unique antiplatelet agent with vasodilatory and vasoprotective effects. Therefore, we hypothesized that cilostazol may affect arterial stiffness. METHODS: We enrolled 161 patients (112 males; mean age, 63 years) who had undergone percutaneous coronary intervention (PCI) for ischemic heart disease. The brachial-ankle pulse wave velocity (baPWV), radial augmentation index (rAI), rAI adjusted for a heart rate of 75 beats/min (rAI75), central systolic blood pressure (cSBP), and central pulse pressure (cPP), were measured at baseline and at the 30-day follow-up. Parameter changes were compared between the cilostazol group (n = 51) and the control group (n = 110). RESULTS: In the cilostazol group, the values for rAI, cSBP, and cPP all improved after 30 days, while the control group displayed no significant interval changes in these parameters. The changes in rAI75 and baPWV did not differ significantly between the two groups. The changes in rAI, cSBP, and cPP were related to brachial systolic blood pressure, brachial diastolic blood pressure, heart rate, and the use of cilostazol and beta-blockers. In a multivariate analysis, the use of cilostazol was identified an independent factor associated with changes in rAI, cSBP, and cPP. CONCLUSIONS: The addition of cilostazol to conventional antiplatelet therapy in patients undergoing PCI may be associated with improvements in rAI, cSBP, and cPP, but not in rAI75 or baPWV. Therefore, the effects of cilostazol might be related to an increased heart rate.
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Humains , Mâle , Pression sanguine , Maladies cardiovasculaires , Études de suivi , Rythme cardiaque , Analyse multifactorielle , Ischémie myocardique , Intervention coronarienne percutanée , Analyse de l'onde de pouls , Facteurs de risque , Rigidité vasculaireRÉSUMÉ
Autosomal dominant polycystic kidney disease (ADPKD) is a systemic disorder associated with various extrarenal complications. The major cardiovascular complications of ADPKD include valvulopathies and vascular ectasia. A 64-year-old man who was diagnosed with ADPKD seven years previously was admitted to our hospital for heart failure. Pelvic computed tomography revealed multiple variable-sized cysts in both kidneys. Transthoracic echocardiography showed enlargement of the left ventricle and left atrium. Severe mitral regurgitation and moderate aortic regurgitation with annuloaortic ectasia were observed. The left main coronary artery was dilated. The patient had various cardiovascular features associated with ADPKD.
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Humains , Adulte d'âge moyen , Insuffisance aortique , Vaisseaux coronaires , Dilatation pathologique , Échocardiographie , Atrium du coeur , Défaillance cardiaque , Ventricules cardiaques , Rein , Insuffisance mitrale , Polykystose rénale autosomique dominanteRÉSUMÉ
A 35-year-old male patient with heart and renal failure and pneumonia was transferred to our department due to recurrent cardiac standstill with syncope. He had been diagnosed as and treated for MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes) syndrome for the past 3 years. Electrocardiography (ECG) showed the Wolff-Parkinson-White pattern, and an echocardiogram showed hypertrophic cardiomyopathy. He developed syncopal attacks intermittently, and ECG monitoring showed intermittent bradycardia. His Holter monitoring showed several episodes of 5-16 seconds of sinus arrest. We conducted an electrophysiological study to evaluate the arrhythmia. During atrial and ventricular extra-stimuli, cardiac standstill developed several times, and the duration of pauses varied from 2.5 to 5.5 seconds. Abrupt asystolic events also developed accompanying syncopal attacks that were not related to the extra-stimuli. We decided to implant a permanent pacemaker. The patient's syncopal episodes disappeared after implantation of a DDD type pacemaker.
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Humains , Mâle , Acidose lactique , Troubles du rythme cardiaque , Bradycardie , Cardiomyopathie hypertrophique , 1,1-Dichloro-2,2-bis(4-chlorophényl)éthane , Électrocardiographie , Électrocardiographie ambulatoire , Coeur , Syndrome MELAS , Maladies musculaires , Pacemaker , Pneumopathie infectieuse , Insuffisance rénale , Arrêt sinusal , SyncopeRÉSUMÉ
Isolated left ventricular noncompaction (LVNC) is a rare disorder caused by embryonic arrest of compaction. LVNC is sometimes associated with other congenital cardiac disorders; however, there have been few reports of its coexistence with a left ventricular aneurysm. A 40-year-old woman was admitted to our hospital for renal infarction. She had a history of embolic cerebral infarction 10 years ago. Transthoracic echocardiography showed prominent trabeculae and deep intertrabecular recesses which are filled with blood from the left ventricular (LV) cavity. A thrombus in the akinetic apical wall was confirmed by contrast echocardiography. Using cardiac computed tomography and magnetic resonance imaging, we rejected a possible diagnosis of suspicion of coronary artery disease. She was diagnosed LVNC with a thrombus in apical aneurysm. Here, we report the first patient in Korea known to have LVNC accompanying LV congenital aneurysm presenting with recurrent embolism.
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Adulte , Femelle , Humains , Anévrysme , Infarctus cérébral , Maladie des artères coronaires , Échocardiographie , Embolie , Infarctus , Corée , Imagerie par résonance magnétique , ThromboseRÉSUMÉ
Lesions with coronary artery aneurysm (CAA) can become complicated during percutaneous coronary intervention. Here, we report a case of a 78-year-old man who developed a rupture, and spontaneous sealing of the CAA occurred after stent implantation, as shown by computed tomography coronary angiography.
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Sujet âgé , Humains , Anévrysme , Malformations , Anévrysme coronarien , Coronarographie , Vaisseaux coronaires , Endoprothèses à élution de substances , Oreille , Intervention coronarienne percutanée , Rupture , EndoprothèsesRÉSUMÉ
BACKGROUND/AIMS: The prognostic impact of empirical anti-tuberculous management according to adenosine deaminase (ADA) levels in patients exhibiting pericardial effusion (PE) has not been established. We evaluated the appropriateness of ADA-guided anti-tuberculous medication for patients with PE. METHODS: From 2001 to 2010, 47 patients with PE and who were diagnosed with either tuberculous pericarditis (TbP) or idiopathic pericarditis (IP) were enrolled. The diagnosis of definite TbP was made by the presence of Tb bacilli or caseous granuloma in pericardial tissue or effusion. The diagnosis of probable TbP was made by the presence of one or more of the following: (1) elevated ADA (> or = 40 IU/L) in pericardial fluid, (2) positive Tb interferon test, or (3) extracardiac presence of Tb. All clinical information was collected by medical record review and telephone contact. RESULTS: Among the 47 patients with PE, 12 were diagnosed with definite TbP; 17, with probable TbP; and 18, with IP. The mean ADA level was significantly higher in patients with definite TbP than in patients with IP (74.97 +/- 36.79 vs. 20.14 +/- 7.39 IU/L; p < 0.001). The optimal ADA cutoff value for diagnosis of definite TbP was 64 IU/L. The median follow-up time was 12.1 months (range, 0.17-100 months). In patients with low levels of ADA (< 40 IU/L), the incidence of death or recurrence did not different between patients who were prescribed anti-tuberculous medication and those who were not. CONCLUSIONS: The ADA level in pericardial fluid was useful for making a rapid diagnosis of tuberculous pericarditis. Even in tuberculosis-endemic areas, patients with ADA < 40 IU/L may have a good prognosis without empirical anti-tuberculous treatment.
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Humains , Adénosine , Adenosine deaminase , Études de suivi , Granulome , Incidence , Interférons , Dossiers médicaux , Organophosphates , Épanchement péricardique , Péricardite , Péricardite tuberculeuse , Pronostic , Récidive , TéléphoneRÉSUMÉ
Streptococcal toxic shock syndrome (STSS) is an acute, progressive illness that manifests with fever, hypotension, and accelerated multi-organ failure. It is usually caused by Group A Streptococcus (Streptococcus pyogenes). STSS due to non-group A streptococci is rare, but its incidence has recently increased. We report here on two cases of STSS caused by Group B Streptococcus (Streptococcus agalactiae) and Group G Streptococcus (Streptococcus dysagalactiae).
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Fièvre , Hypotension artérielle , Incidence , Choc septique , Streptococcus , Streptococcus agalactiaeRÉSUMÉ
It is known that the toe-flexors exert some power generation in ankle plantar flexion. However, there has been no paper published in which the power generation was quantified. The purpose of this paper, therefore, is to quantify the amount of contribution of the toe-flexors to the ankle plantar-flexion in normal and rapid walking using the kinetic data of three dimensional gait analysis system. In order to restrict the action of the toe-flexors, we designed special braces which can be applied to the forefeet of the examinee during walking. We performed the gait analysis in ten normal adult volunteers with and without braces, and evaluated the moment and power of toe-flexors during terminal stance and pre-swing phase of gait cycle. Gait analysis was done with the VICON 3-dimensional motion analysis system (VICON, Oxford Metrics, Oxford, England) and 2 force plates (AMTI, Advanced Mechanical Technoiogy, Newton, MA, U.S.A,). The kinetic results are as follows: l. Average speeds of normal and rapid walking were 1.12m/sec and 1.41m/sec respectiveIy. 2. In normal walking, peak ankle plantar-tlexion moment decreased 5.5% with braces, and sum of ankle plantar-flexion moment decreased 12.3% with braces. Both of the results were not significant statistically (p>0.05). Peak ankle power generation decreased 11.0% with braces, and sum of ankle power generation decreased 10.4% with braces. These decreases were also insignificant statistically (p>0.05). 3. In rapid walking, peak ankle plantarflexion moment decreased 26.7% with braces. The decrease was horderline significant statistically (p=0.062). The sum of ankle plantar-tlexion moment decreased 26.6% with braces, but the decrease was not significant statistically (p>0.05). Peak ankle power generation decreased 40.2% with braces, and sum of ankle power generation decreased 37.9% with braces. These decreases showed borderline significance statistically (p=0.062). In conclusion, toe-flexors may contribute about 10% of the total ankle plantar-flexion power generation, and the contribution will be increased with increase of walking velocity. We must be very careful to sacrifice the toe-flexors in cases with weak triceps power.
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Adulte , Humains , Cheville , Orthèses de maintien , Démarche , Orteils , Bénévoles , Marche à piedRÉSUMÉ
Experimental findings have suggested that the metabolic activities of articular cartilage can be influenced by mechanical stimuli. Our recent mathematical analysis predicted that cyclic compressive loading may create periods of intermittent negative hydrostatic pressure within the cartilage extracellular matrix. Therefore, we hypothesize that intermittent negative hydrostatic pressure, created in the cartilage extracellular matrix during dynamic compression, has a stimulative effect on the biosynthesis of chondrocytes. In order to test this hypothesis, the present study developed a custom designed negative pressure generator to subject a monolayer culture of chondrocytes to an intermittent negative pressure. It was found that the intermittent negative pressure produced a 40% increase in proteoglycan and a l7% increase in non-collagenous protein synthesis during the pressurization period(p (0.05). The collagenous protein synthesis was not affected by the intermittent negative pressure regimen used in this study. After the intermittent negative pressurization, the metabolic activities of the chondrocytes returned to normal(control level). The intermittent negative pressure also produced an increase in the mRNA signals for aggrecan. Therefore, we conclude that intermittent negative pressure may be one of the major mechanical stimulators of chondrocytes in articular cartilage during dynamic compression.