Impact of Physician-Coordinated Intensive Follow-Up on Long-Term Medical Costs in Patients with Unstable Angina Undergoing Percutaneous Coronary Intervention.

BACKGROUND: To investigate the impact of professional physician-coordinated intensive follow-up on long-term expenditures after percutaneous coronary intervention (PCI) in unstable angina (UA) patients. METHODS: In this study, there were 669 UA patients who underwent successful PCI and followed up for 3 years, then divided into the intensive follow-up group (N = 337), and the usual follow-up group (N = 332). Patients were provided with detailed discharge information and individualized follow-up schedules. The intensive group received the extra follow-up times and medical consultations, and all patients were followed up for approximately 3 years. RESULTS: At the 3-year mark after PCI, the cumulative major adverse cardiac events (MACE), recurrence of myocardial ischemia, cardiac death, all-cause death and revascularization in the intensive group were lower than in the usual group. Additionally, the proportion of good medication adherence was significantly higher than in the usual group (56.4% vs. 46.1%, p < 0.001). The hospitalization daytime, total hospitalization cost and total medical cost in the intensive group were lower. Multiple linear regression showed that diabetes, hypertension, intensive follow-up and good medication adherence were associated with emergency and regular clinical cost (p < 0.05), the re-hospitalization cost (p < 0.05) and the total medical cost (p < 0.05) of patient care. Intensive follow-up and good adherence were negatively correlated with the cost of re-hospitalization (standardized coefficients = -0.132, -0.128, p < 0.05) and total medical costs (standardized coefficients = -0.072, -0.086, p < 0.05). CONCLUSIONS: Intensive follow-up can reduce MACE, improve medication adherence and save long-term total medical costs, just by increasing the emergency and regular clinical visits cost in UA patients after PCI.

ACEI attenuates the progression of CCl4-induced rat hepatic fibrogenesis by inhibiting TGF-beta1, PDGF-BB, NF-kappaB and MMP-2,9.

AIM: Angiotensin II has pro-fibrotic function in the liver. Blockade of the renin-angiotensin-aldosterone-system (RAAS) attenuates hepatic fibrosis. The aim of the present study was to determine the mechanism of angiotensin-converting enzyme inhibitor (ACEI) on the progression of rat hepatic fibrosis. METHODS: Forty male Wistar rats were divided into three groups. Model group (Mo): The rats were injected subcutaneously with 40% of CCl(4) 0.25 mL/100 g. Perindopril group (Pe): The rats were injected subcutaneously with 40% of CCl(4). Perindopril, equivalent to 2 mg/(kg.d), was administrated. Control group (Nc): the rats were treated with olive oil only. After 4 and 6 wk, the rats were killed. The liver sections were stained with Masson. The protein expressions of AT1R, TGF-beta1 and PDGF-BB were examined by Western blot. Nuclear factor kappaB (NF-kappaB) DNA binding activity was examined by EMSA (Electrophoretic gel mobility shift assay). Matrix metalloproteinase-2,9 (MMP-2,9) activity was assessed by zymography. Serum laminin (LN) and hyaluronic acid (HA) were measured using radioimmunoassays. RESULTS: Using Western blot, we clearly provided direct evidence for the expression of AT1R in liver. The expression was up-regulated when fibrogenesis occurred. Perindopril treatment significantly reduced mean fibrosis score, protein levels of AT1R, TGF-beta1 and PDGF-BB, serum levels of HA and LN, and the activity of MMP-2,9. NF-kappaB DNA binding activity markedly increased in model group, perindopril treatment considerably reduced NF-kappaB DNA binding activity. CONCLUSION: Perindopril attenuates CCl(4)-induced hepatic fibrogenesis of rat by inhibiting TGF-beta1, PDGF-BB, NF-kappaB and MMP-2,9.

[Angiotensin II and aldosterone stimulate alpha1-(I) procollagen mRNA expression in hepatic stellate cells via activation of ERK1/2 and AP-1].

OBJECTIVE: To investigate the signal transduction mechanism underlying the effects of angiotensin II (Ang II) and aldosterone (Aldo) on the signal passageway of active protein-1 (AP-1). METHODS: In vitro, Hepatic stellate cells (HSCs) of the line HSC-T6 were cultured and treated with Ang II or Aldo, the principal effector molecules of the renin-angiotensin-aldosterone system (RAAS) for 10, 30, 60, 120, and 180 minutes respectively. The protein expression of phospho-P42/44 was detected by Western blotting. In addition, HSC-T6 cells were preincubated for 60 min with U0126, an inhibitor of MAPK/ERK kinase, irbesartan, an AT-1 receptor blocker, N-acetylcysteine (NAC), antioxidant, angiotensin converting enzyme inhibitor (ACEI), or tumor necrosis factor alpha (TNFalpha) prior to exposure to Ang II or Aldo. Then the protein expression of phospho-P42/44 was measured by Western blotting. The DNA biding activity of AP-1 was analyzed by electrophoretic gel mobility shift assay (EMSA). By means of RT-PCR, the mRNA expression of alpha1 (I) procollagen was detected. RESULTS: The levels of phopho-ERK1/2 protein increased after the treatment of Ang II and Aldo at all time points and both peaked 10 minutes after (both P < 0.01). The levels of phopho-ERK1/2 protein of the irbesartan + Ang II and U0126 + Ang II groups were significantly lower than that of the Ang II group (both P < 0.01). The level of phopho-ERK1/2 protein of the Ang II group was lower than that of the TNFalpha group, however, was especially significantly lower than that of the Ang II + TNFalpha group (P < 0.01). The level of phopho-ERK1/2 protein of the U0126 + Aldo group was significantly lower than that of the Aldo group (P < 0.01). The phopho-ERK1/2 protein level of the NAC + Aldo group was not significantly different from that of the Aldo group (P > 0.05). The phopho-ERK1/2 protein level of the Aldo group was lower than that of the TNFalpha group, however, was especially significantly lower than that of the Aldo + TNFalpha group (P < 0.01). The AP-1 DNA binding protein increased after the treatment of Ang II and peaked 30 min after. U0126, irbesartan, and NAC, as well as ACEUI, significantly inhibited the increased AP-1 DNA binding activity induced by Ang II. The AP-1 DNA binding protein increased after the treatment of Aldo and peaked twice, 30 min and 240 min after. U0126 and NAC significantly and NAC partly inhibited the increased AP-1 DNA binding activity induced by Aldo. CONCLUSION: Stimulation of HSC by Ang II and Aldo results in activation of AP-1 via ERK1/2 pathway leading to up-regulation of AP-1 target gene alpha1 (I) procollagen mRNA expression.

[Effects of angiotensin II and aldosterone on NF-kappaB binding activity in hepatic stellate cells].

OBJECTIVE: To investigate the signal transduction mechanism underlying the effects of angiotensin II (AngII) and aldosterone (Aldo) on nuclear factor-kappaB (NF-kappaB) DNA binding activity. METHODS: Sixty male Wistar rats were randomly divided into 4 groups: model group (Mo group), injected with CCl(4) subcutaneously twice a week to establish a model of hepatic fibrosis; perindopril group (Pe group), injected with CCl(4) subcutaneously twice a week and perfused with perindopril once a day; losartan group (Lo group), injected with CCl(4) subcutaneously twice a week and perfused with losartan once a day; and control group (Nc group), injected with olive oil subcutaneously. The rats were killed in batches respectively 4 and 6 weeks after and their livers were collected to undergo Masson staining and be observed by light microscope. Electrophoretic gel mobility shift assay (EMSA) was used to detect the NF-kappaB DNA binding activity in the liver tissues. Western blotting was used to detect the expression of IkappaBalpha in the plasma protein. Hepatic stellate cells (HSCs)-T6 were cultured and preincubated for 1 h or not with U0126 (an inhibitor of MAPK/ERK kinase MEK), irbesartan (an AT-1 receptor blocker), and N-acetylcysteine (NAC, an antioxidant), angiotensin-converting enzyme inhibitor (ACEI), or tumor necrosis factor alpha (TNFalpha) prior to exposure to AngII or Aldo for 0.5 h, 1 h, 2 h, and 4 h respectively. The binding activities of NF-kappaB DNA were observed by EMSA. The expression of IkappaBalpha protein was detected with Western blotting. Histochemistry was used to detect the expression of NF-kappaB p65. RT-PCR was used to detect the expression of TNFalpha mRNA in HSC-T6 cells. RESULTS: The binding activity to NF-kappaB of the liver tissues was the strongest in the Mo group, followed by the Pe and Lo groups and Nc group. The IkappaBalpha expressions in liver tissues 4 and 6 weeks after the beginning of experiment in the Pe and Lo groups were significantly stronger than that in the Mo group (both P < 0.05). 0.5 hour after the intervention of AngII the DNA binding activity of the HSCs began to increase and peaked 1 hour later and then gradually decreased. The increase of NF-kappaB activity induced by AngII could be inhibited by irbesartan, ACEI and NAC pretreatment and could not be inhibited by U0126 pretreatment. Combined action of AngII and TNFalpha significantly increased the NF-kappaB DNA binding activity. The IkappaBalpha expression began to decrease 0.5 hour after the intervention of AngII and reached the lowest value 2 hours after. The expression of IkappaBalpha protein was increased by ACEI (P < 0.05), irbesartan and NAC (both P < 0.01). EMSA showed that 0.5 hour after the intervention of Aldo the DNA binding activity began to be increased and peaked by 1 hour and then began to be decreased. NAC, but not U0126 partly inhibited the increased of NF-kappaB activity induced by Aldo. Combined action of Aldo and TNFalpha significantly increased the NF-kappaB activity. Aldo increased the expression of IkappaBalpha protein in the HSCs at different time points (all P < 0.05). 0.5 hour after the AngII intervention the IkappaBalpha protein expression began to decrease and reach the lowest value 1 hour later and then began to increase 2 hours later. the IkappaBalpha protein expression was significantly decreased in the NAC and NAC+ Aldo intervention groups (both P < 0.05). There was no significant difference in IkappaBalpha protein expression between the Aldo intervention group and U0126 + Aldo, TNFalpha, and Aldo + TNFalpha treatment groups (all P > 0.05). Before stimulation, NF-kappaB was expressed in the plasma of HSCs, however, after the stimulation of AngII or Aldo for 1 hour it was expressed in the nuclei, and then transferred from the nuclei to the plasma 4 hours after the stimulation. However, little nuclear transfer was observed after pretreatment of NAC followed by AngII or Aldo intervention. The TNFalpha mRNA expression was significantly increased in the AngII and Aldo treatment groups in comparison with the control group (both P < 0.05). The TNFalpha mRNA expression was significantly weaker in the irbesartan + AngII, NAC + AngII, and ACEI groups in comparison with the AngII group (all P < 0.05). CONCLUSION: Stimulation of NF-kappaB activity mediates hepatic fibrosis induced by intrahepatic renin-angiotensin-aldosterone system (RAAS).

[Aldosterone stimulating PDGF-B expression in HSC via activation of EGR-1].

OBJECTIVE: It is known that intrahepatic renin-angiotensin-aldosterone system (RAAS) plays a key role in liver fibrogenesis. Aldosterone (Aldo), the principal effector molecule of the RAAS, exerts local effects on cell growth and fibrogenesis. However, the signal transduction mechanisms underlying the effects of Aldo on hepatic fibrogenesis remain to be fully elucidated. The present study aims to investigate the signal transduction mechanism underlying the effects of Aldo on extracellular signal-regulated kinase 1/2 (ERK1/2), early growth response-1 (EGR-1) and on the platelet-derived growth factor-B (PDGF-B). METHODS: In vitro, hepatic stellate cell (HSC)-T6 cell line was treated with Aldo for 10 min, 0.5 h, 1 h, 2 h and 3 h. Protein expression of phospho-p42/44 was detected by Western blot. In addition, HSC-T6 were preincubated for 1 h or not at all with U0126 (an inhibitor of the MAPK/ERK kinase), and antioxidant-N-acetylcysteine (NAC) prior to exposure to Aldo for the indicated times. Protein expressions of phospho-p42/44 and PDGF-B were measured by Western blot. DNA biding activity of EGR-1 was analyzed by electrophoretic gel mobility shift assay (EMSA). By means of immunohistochemistry, expression of PDGF-B was detected. RESULTS: Aldo induced phospho-p42/44 expression could be abrogated by U0126; NAC did not inhibit phospho-p42/44 expression. Gel shift study showed that stimulation of HSC by Aldo markedly increased the EGR-1 DNA binding activity, which was abrogated by U0126, reaching a maximum at 60 minutes, and then declined progressively. NAC did not reduce the EGR-1 activity. Aldo increased the PDGF-B protein level in HSC, which was not attenuated by NAC and U0126. CONCLUSIONS: Stimulation of HSC by Aldo results in activation of EGR-1 via ERK1/2 pathway, leading to up-regulation of PDGF-B expression.

[Aldosterone stimulates alpha1-(1) procollagen mRNA expression in HSC via activation of ERK1/2 and AP-1].

OBJECTIVE: It has been known that the intrahepatic renin-angiotensin-aldosterone system (RAAS) plays a key role in the fibrogenesis in livers. Aldosterone (Aldo), the principal effector molecule of the RAAS, exerts local effects on cell growth and fibrogenesis. However, the signal transduction mechanisms underlying the effects of Aldo on hepatic fibrogenesis remain to be fully elucidated. The present study aims to investigate the signal transduction mechanism underlying the effects of Aldo on the signal passageway of active protein-1 (AP-1). METHODS: In vitro, HSCs-T6 cell line was treated with Aldo for 10 min, 30 min, 60 min, 120 min and 180 min, and protein expression of Phospho-P42/44 was detected by Western blot. In addition, HSCs-T6 cell line was preincubated for 60 min or not with U0126 (an inhibitor of the MAPK/ERK kinase), and also with antioxidant-N-acetylcysteine (NAC) prior to exposure to Aldo for the indicated times. Protein expression of Phospho-P42/44 was measured by Western blot. DNA biding activity of AP-1 was analyzed by electrophoretic gel mobility shift assay (EMSA). By means of RT-PCR, expression of alpha1(1) procollagen mRNA was detected. RESULTS: Aldo stimulated HSC via extracellular signal-regulated kinase (ERK1/2) pathway. Time course experiments showed that Aldo induced Phospho-P42/44 expression, which was abrogated by U0126, reaching a maximum at 10 minutes, and then declined progressively. NAC inhibited the Phospho-P42/44 expression. EMSA showed that stimulation of HSC by Aldo markedly increased AP-1 DNA binding activity. U0126 markedly reduced AP-1 DNA binding activity induced by Aldo; NAC partly decreased AP-1 activity induced by Aldo. Aldo up-regulated expression of alpha1(1) procollagen mRNA, which was attenuated by U0126 and NAC. CONCLUSION: Stimulation of HSC by Aldo results in activation of AP-1 via ERK1/2 pathway, leading to up-regulation of AP-1 target gene alpha1(1) procollagen mRNA expression.

Association between left ventricular end-diastolic pressure and coronary artery disease as well as its extent and severity.

Patients with myocardial ischemia exhibit increased left ventricular end-diastolic pressure (LVEDP). The study was to evaluate the relationship between LVEDP measured by left cardiac catheterization and coronary artery disease (CAD) as well as its extent and severity evaluated by coronary angiography (CAG). 912 patients who underwent CAG and left cardiac catheterization were enrolled. There were 313 patients without CAD and 599 with CAD according to CAG. The extent and severity of coronary artery was evaluated by number of vessels and Gensini score. Analyze the correlation of LVEDP and CAD as well as its extent and severity. LVEDP was significantly higher in CAD patients than non-CAD (9.58±5.78 mmHg vs 10.9±5.46 mmHg, P<0.001), and was correlated independently with the presence of CAD (OR = 0.11, per 5 mmHg increase, 95% CI 1.02-1.29, P = 0.02). LVEDP was increased with an increase of number of vessels. By linear regression analysis, LVEDP was significantly associated with Gensini score (standardized ß = 0.034, P = 0.001). In non-CAD group, LVEDP was only correlated with age (r = 0.123, P = 0.030). In conclusion, our findings suggest that elevated LVEDP was significantly associated with CAD as well as its extent and severity. LVEDP was only correlated with age in non-CAD patients. LVEDP measurement provides incremental clinical value for CAD and non-CAD patients.

Changes in the expression of angiotensin II type 1 receptor in the development of liver fibrosis.

OBJECTIVE: To detect the expression of angiotensin II type 1 receptor (AT1R) in the different stages of human liver fibrosis. METHODS: The morphology and ultrastructure of hepatic stellate cells (HSC) in hepatic sinusoids were studied by transmission electron microscopy, collagen I (col I) was tested by immunohistochemical method, an indirect immunofluorescence labeling method was used to detect AT1R, and semiquantitative RT-PCR was used to detect AT1R mRNA. RESULTS: Positive expression of AT1R was mainly distributed in the periphery of hepatic lobules and in the cytoplasm of HSC in the sinusoids. In normal liver tissue from 12 cases, positive expression of AT1R was seen in 8, whereas in 18 fibrotic livers, all showed positive expression. Cells that positively expressed AT1R were significantly more abundant in the fibrotic liver group than in the normal liver group (P < 0.001), and were significantly increased with an increase in the collagenous surface area. The relative expression level of AT1R mRNA in the fibrotic liver group was also higher than in the normal liver group (P < 0.01). CONCLUSIONS: The expressions of both AT1R and AT1R mRNA increased significantly with the degree of liver fibrosis, so angiotensin II and its receptor are probably important in the development of liver fibrosis.

[Effect of ACE-I and AT-1 receptor blocker on the progression of CCl(4)-inducing rat hepatic fibrogenesis].

OBJECTIVE: The aim of the present study was to determine the effects of angiotensin-converting enzyme inhibitor (ACE-I) and angiotensin II type 1 receptor (AT-1 receptor) blocker on the progression of rat hepatic fibrosis induced by CCl4. METHODS: 60 male wistar rats weighting about 250 g were divided into 4 groups. Model group (Mo): The rats were injected with 40% CCl(4) 0.25 ml/100 g subcutaneously three times a week. Perindopril group (Pe): The rats were injected with 40% CCl(4). Perindopril, equivalent to 2 mg x kg(-1) x d(-1), was given i.g. Losartan group (Lo): The rats were injected with 40% CCl(4). Losartan, equivalent to 50 mg x kg(-1) x d(-1), was given i.g. Control group (Nc): the rats were injected with olive oil only. After 4, 6 weeks, morphological examination was based on microscopy. RT-PCR was utilized to detect gene expression of AT-1 receptor in the liver. Meanwhile, the protein expressions of AT-1 receptor, TGF-beta1 and PDGF-BB in liver tissue were examined by Western blot. The activity of matrix metalloproteinase-2 (MMP-2) was assessed by zymography. Serum laminin (LN) and hyaluronic acid (HA) were measured using radioimmunoassays. RESULTS: RT-PCR and Western blot revealed that there was a up-regulation in AT-1 receptor expression in model group compared with control group. Both of perindopril and losartan treatment significantly reduced mean fibrosis score, messenger RNA and protein levels of AT1 receptor, protein levels of TGF-beta1 and PDGF-BB, Serum levels of HA and LN, and MMP-2 activity. CONCLUSION: These results suggest that angiotensin IImay play an important role in fibrosis of liver. Perindopril and losartan may have inhibiting effects on CCl(4)-induced hepatic fibrogenesis of rat.

[Endoscopic diagnosis and treatment of the early-stage malignant colorectal polyp and follow-up study].

In the past 20 years we have performed endoscopic removal of colorectal polyps in 4 000 cases, and thorough histological examination of the removed polyps identified 121 cases of early-stage malignant polyp. According to the depth of malignant invasion and whether malignant remnants were present after the initial surgical removal, conservative treatment or radical operation was implemented. During the follow-up study, endoscopy was performed once each year in all the patients with malignancies. No recurrence was found in the 33 patients with mucosa cancer or in the 27 patients with type I submucosa cancer who did not receive radical operation due to absence of malignant remnants or in the 38 patients with type II submucosa cancer who had the radical operation. Relapse occurred in 1 patient with malignant remnant and in another 3 cases of type II submucasa cancer without radical operation.

[Expressions of angiotensin II type 1 receptor mRNA in fibrotic and normal liver tissues].

OBJECTIVE: To investigate the expression profile of angiotensin type 1 receptor (AT1R) mRNA in fibrotic and normal liver tissues. METHODS: Semi-quantitative RT-PCR was used to detect the expression of AT1R mRNA in 18 specimens of fibrotic liver tissues adjacent to liver cancers and 12 normal liver tissue specimens. Specific AT1R product and GAPDH product used as internal control were both amplified by RT-PCR, and the ratio of their integrated optical densities calculated to estimate the relative quantity of AT1R mRNA expression. RESULTS: The relative mRNA expression of AT1R in fibrotic liver tissues was significantly higher than that of normal liver tissues (1.27+/-0.45 vs 0.71+/-0.21, P < 0.01). CONCLUSION: AT1R may play an important role in the development of hepatic fibrosis.

Effects of angiotensin II and losartan on the growth and proliferation of hepatic stellate cells.

OBJECTIVE: To investigate the effects of angiotensin II (AngII) and AT1a blocker losartan on growth and proliferation of rat hepatic stellate cells (HSCs). METHODS: Rat HSCs were isolated, cultured and identified, followed by incubation with AngII or losartan at different concentrations. The cell growth and proliferation were assessed via cell counting and MTT assay, and the effects of the agents on HSC DNA synthesis evaluated by way of (3)H-thymidine incorporation ((3)H-TDR). RESULTS: AngII (1 x 10(-9) to 1 x 10(-7) mol/L) stimulated HSC proliferation as demonstrated by cell counting, MTT assay and thymidine incorporation test (P < 0.05), but such effect was not observed at lower doses (<1 x 10(-9) mol/L). Losartan had significant inhibitory effect on HSC growth at the concentration of 1 x 10(-8) to 1 x 10(-6) mol/L (P < 0.05), but not at lower doses (<1 x 10(-8) mol/L). Co-stimulation of the cells with losartan and AngII did not result in a significant increase in cell number as compared with the control group (P > 0.05). CONCLUSION: Rapid proliferation of rat HSCs occurs in response to AngII treatment, but is inhibited after AT1a receptor is blocked with the antagonist losartan.

Detection of soluble tumor necrosis factor-p55 levels in the serum and ascitic fluid of patients with hepatocellular carcinoma.

OBJECTIVE: To examine soluble tumor necrosis factor receptor-p55 (sTNFR-p55) levels in the serum and ascitic fluid and investigate the significance of this examination in assessment of the clinical status of patients with primary hepatocellular carcinoma (HCC). METHODS: Enzyme-linked immunosorbent assay (ELISA) was used to examine sTNFR-p55 levels in the serum and ascitic fluid in 25 patients with HCC and 25 with liver cirrhosis (LC). RESULTS: sTNFR-p55 levels in the serum and ascitic fluid in patients with HCC were significantly higher than those in patients with LC and controls (P=0.001). No significant difference was found between LC and the control in terms of serum sTNFR-p55 levels (P=0.19). Positive correlation was observed between sTNFR-p55 levels in the serum and in ascitic fluid of patients with HCC and LC (r=1.000, P<0.001). Logistic regression revealed that in patients with HCC, serum sTNFR-p55 levels were positively correlated with TBil and AFP in the peripheral blood (r=0.524, P=0.01 and r=0.234, P=0.03, respectively). CONCLUSIONS: Increased sTNFRs-p55 levels in the serum and ascitic fluid reflect abnormal immune status of the patients with HCC and help predict the development of tumor.

[Perindopril attenuates the progression of CCl4-inducing rat hepatic fibrosis].

OBJECTIVES: The aim of the present study was to determine the effects of angiotensin-converting enzyme inhibitor, perindopril, on the progression of rat hepatic fibrosis induced by CCl4. METHODS: Male wistar rats weighting about 250g were treated with perindopril (2mg/kg, daily gavage), except for model group and control group. After 4, 6 weeks, morphological examination was based on microscopy. RT-PCR was utilized to detect gene expression of angiotensin II type 1 receptor (AT1 receptor) in the liver. Meanwhile, the protein expressions of AT1 receptor, transforming growth factor beta 1 (TGF-beta1) and platelet-derived growth factor-BB (PDGF-BB) in liver tissue were examined by Western blot. The activity of matrix metalloproteinase-2 (MMP-2) was assessed by zymography. Serum laminin (LN) and hyaluronic acid (HA) were measured using radio-immunity technique. RESULTS: RT-PCR and Western blot revealed that there was a up-regulation in AT1 receptor expression in model group compared with control group. Perindopril treatment significantly reduced mean fibrosis score, messenger RNA and protein levels of AT1 receptor, protein levels of TGF-beta1 and PDGF-BB, Serum levels of HA and LN, and MMP-2 activity. CONCLUSION: These results suggest that angiotensin II may play an important role in fibrosis of liver. Perindopril may have a inhibiting effect on CCl4-induced hepatic fibrogenesis of rat.