Disappearance of perihepatic lymph node enlargement after hepatitis C viral eradication with direct-acting antivirals.

Perihepatic lymph node enlargement (PLNE) which has been shown to be negatively associated with hepatocellular carcinoma (HCC) occurrence is frequently observed in chronic liver disease; however, changes in the state of perihepatic lymph nodes after eradication of hepatitis C virus (HCV) have not been investigated yet. We aimed to evaluate this issue. We enrolled 472 patients with chronic HCV infection who achieved viral eradication with direct-acting antivirals (DAA). We investigated whether the status of perihepatic lymph nodes changed before and after HCV eradication (primary endpoint). We also evaluated the association between PLNE and clinical findings such as liver fibrosis or hepatocellular injury before HCV eradication (secondary endpoint). Perihepatic lymph node enlargement was detected in 164 of 472 (34.7%) patients before DAA treatment. Surprisingly, disappearance of PLNE was observed in 23.8% (39 patients) of all PLNE-positive patients after eradication of HCV. Disappearance of PLNE was not associated with baseline clinical parameters or changing rates of clinical findings before and after DAA treatment. At baseline, presence of PLNE was significantly associated with a lower serum HCV-RNA level (P = .03), a higher serum AST level (P = .004) and a higher ALT level (P < .001) after adjustment for sex and age. In conclusion, PLNEs became undetectable after DAA treatment in 23.8% of PLNE-positive patients. Further study with a longer follow-up period is needed to clarify the clinical importance of this phenomenon especially in relationship with the risk of HCC development.

Risk factors for hepatocellular carcinoma in hepatitis C patients with normal alanine aminotransferase treated with pegylated interferon and ribavirin.

Pegylated interferon (Peg-IFN) plus ribavirin combination therapy is effective in patients with hepatitis C virus (HCV) infection and normal alanine aminotransferase levels (NALT). However, it remains unclear whether the risk of hepatocellular carcinoma (HCC) incidence is actually reduced in virological responders. In this study, HCC incidence was examined for 809 patients with NALT (ALT ≤ 40 IU/mL) treated with Peg-IFN alpha-2b and ribavirin for a mean observation period of 36.2 ± 16.5 months. The risk factors for HCC incidence were analysed by Kaplan-Meier method and Cox proportional hazards model. On multivariate analysis among NALT patients, the risk of HCC incidence was significantly reduced in patients with sustained virological response (SVR) or relapse compared with those showing nonresponse (NR) (SVR vs NR, hazard ratio (HR): 0.16, P = 0.009, relapse vs NR, HR: 0.11, P = 0.037). Other risk factors were older age (≥65 years vs <60 years, HR: 6.0, P = 0.032, 60-64 vs <60 years, HR: 3.2, P = 0.212) and male gender (HR: 3.9, P = 0.031). Among 176 patients with PNALT (ALT ≤ 30 IU/mL), only one patient developed HCC and no significant risk factors associated with HCC development were found. In conclusion, antiviral therapy for NALT patients with HCV infection can lower the HCC incidence in responders, particularly for aged and male patients. The indication of antiviral therapy for PNALT (ALT ≤ 30 IU/mL) patients should be carefully determined.

Mcl-1 and Bcl-xL regulate Bak/Bax-dependent apoptosis of the megakaryocytic lineage at multistages.

Anti-apoptotic Bcl-2 family proteins, which inhibit the mitochondrial pathway of apoptosis, are involved in the survival of various hematopoietic lineages and are often dysregulated in hematopoietic malignancies. However, their involvement in the megakaryocytic lineage is not well understood. In the present paper, we describe the crucial anti-apoptotic role of Mcl-1 and Bcl-xL in this lineage at multistages. The megakaryocytic lineage-specific deletion of both, in sharp contrast to only one of them, caused apoptotic loss of mature megakaryocytes in the fetal liver and systemic hemorrhage, leading to embryonic lethality. ABT-737, a Bcl-xL/Bcl-2/Bcl-w inhibitor, only caused thrombocytopenia in adult wild-type mice, but further induced massive mature megakaryocyte apoptosis in the Mcl-1 knockout mice, leading to severe hemorrhagic anemia. All these phenotypes were fully restored if Bak and Bax, downstream apoptosis executioners, were also deficient. In-vitro study revealed that the Jak pathway maintained Mcl-1 and Bcl-xL expression levels, preventing megakaryoblastic cell apoptosis. Similarly, both were involved in reticulated platelet survival, whereas platelet survival was dependent on Bcl-xL due to rapid proteasomal degradation of Mcl-1. In conclusion, Mcl-1 and Bcl-xL regulate the survival of the megakaryocytic lineage, which is critically important for preventing lethal or severe hemorrhage in both developing and adult mice.

Endothelium-derived nitric oxide regulates arterial elasticity in human arteries in vivo.

Arterial elasticity is determined by structural characteristics of the artery wall and by vascular smooth muscle tone. The identity of endogenous vasoactive substances that regulate elasticity has not been defined in humans. We hypothesized that NO, a vasodilator released constitutively by the endothelium, augments arterial elasticity. Seven healthy young men were studied. A 20-MHz intravascular ultrasound catheter was introduced through an arterial sheath to measure brachial artery cross-sectional area, wall thickness, and intra-arterial pressure. After control was established, indices of elasticity (pressure-area relationship, instantaneous compliance, and stress-strain, pressure-incremental elastic modulus (E(inc)), and pressure-pulse wave velocity relationships) were examined over 0 to 100 mm Hg transmural pressure obtained by inflation of an external cuff. Thereafter, the basal production of endothelium-derived NO was inhibited by N(G)-monomethyl-L-arginine (L-NMMA) (4 and 8 mg/min). Finally, nitroglycerin (2.5 and 12.5 microgram/min), an exogenous donor of NO, was given to relax the vascular smooth muscle. Elasticity was measured under all of these conditions. L-NMMA (8 mg/min) decreased brachial artery area (P=0.016) and compliance (P<0.0001) and increased E(inc) (P<0.01) and pulse wave velocity (P<0.0001). Nitroglycerin (12.5 microgram/min) increased brachial artery area (P<0.001) and compliance (P<0.001) and decreased pulse wave velocity (P=0.02). NO, an endothelium-derived vasodilator, augments arterial elasticity in the human brachial artery. Loss of constitutively released NO associated with cardiovascular risk factors may adversely affect arterial elasticity in humans.

Relation between vascular morphologic changes during stent implantation and the magnitude of in-stent neointimal hyperplasia.

Intimal hyperplasia usually occurs after balloon overstretch injury or wire coil stimuli to coronary arteries. We examined whether the degree of vessel wall stretch during coronary stent placement could predict the amount of in-stent neointimal hyperplasia after a 6-month follow-up. Serial (preintervention, postballooning, poststent implantation, and a follow-up after 6 months) intravascular ultrasound (IVUS) was used to study 457 consecutive cross-sectional areas in 28 patients. IVUS imaging, using a motorized pullback system at 0.5 mm/s, allowed 1-mm axial increment measurements of the total vascular, stent, and lumen cross-sectional areas. The mean total vascular area changed from 10.89 +/- 2.50 mm2 before to 11.27 +/- 2.49 mm2 after ballooning, to 12.80 +/- 2.59 mm2 after stenting, and to 12.58 +/- 2.41 mm2 at follow-up (p < 0.0001). The mean lumen area changed from 3.36 +/- 1.95 mm2 before to 4.21 +/- 1.65 mm2 after ballooning, to 5.16 +/- 1.09 mm2 after stenting, and to 3.57 +/- 1.23 mm2 at follow-up (p < 0.0001). The mean stent area decreased from 5.25 +/- 1.17 mm2 after stenting to 5.09 +/- 0.90 mm2 at follow-up (p < 0.0001). Stepwise logistic regression analysis showed that delta total vascular area (after stent implantation - before intervention) was a strong predictor of the amount of intimal hyperplasia (r = 0.57, p < 0.0001). Vascular overstretch caused by the stenting procedure promotes intimal hyperplasia in proportion to the degree of sectional vascular stretch.

Review article: the stages of gastrointestinal carcinogenesis--application of rodent models to human disease.

The development of gastrointestinal cancer in humans and animals occurs through a consecutive series of stages termed initiation, promotion and progression. The characterization of each of these stages has been elucidated in several model systems as well as in human neoplasms. Both single, putatively initiated cells and preneoplastic foci have been identified by marker protein differences as well as by mutational changes. The promotion stage involves the clonal expansion of single initiated cells. Such expansion can be rapidly reversed by a variety of means, of which acute fasting (as exemplified in rat hepatocarcinogenesis) is among the most rapid and efficient. This reversal involves a selective apoptosis of preneoplastic cells and preneoplastic lesions, associated with a marked increase in expression of the proto-oncogene c-myc. Transition of cells from the stage of promotion to that of progression initially involves specific karyotypic alterations, as noted in both the rat liver model and human colon carcinogenesis. In the former, the transition appears to be associated with enhanced expression of the H119 imprinted putative tumour suppressor gene. Thus, the use of model systems may be applied directly to the human circumstance, increasing the potential both for rational prevention of gastrointestinal neoplasia and for new approaches to the therapy of neoplastic disease in the progression stage.

Primary cardiac malignant fibrous histiocytoma in the right ventricular infundibulum treated with a cavo-pulmonary shunt and coronary embolization.

A 51-year-old woman presented with progressive right ventricular infundibular wall thickening and outflow obstruction. She had had an aorto-coronary bypass for left main coronary artery disease 1 year after radiation therapy for left mammary cancer. Enhanced computed tomography showed a mass in the right ventricular free wall with no connection to the mediastinum; the tumor extended into the main pulmonary artery, but there was no other evidence of a primary or metastatic tumor. A biopsy specimen was obtained and based on the microscopic and immuno-histochemical findings (vimentin and Kp-1 positive) the diagnosis was primary cardiac malignant fibrous histiocytoma, which is very rare. A cavo-pulmonary artery connection lessened her symptoms, but embolization of the coronary artery to try and to reduce the mass had minimal effect. Four months after the tumor was diagnosed she died of extended pulmonary artery obstruction.

Effect of distal stenosis of internal thoracic artery bypass grafts on longitudinal phasic blood flow velocity characteristics.

BACKGROUND: Left internal thoracic artery (LITA) bypass conduits show gradual longitudinal transition in their phasic flow velocity patterns from the proximal to distal segments, but little is known about the influence of distal stenosis, particularly early after surgery, on that characteristic. The purpose of this study was to evaluate the influence of distal stenosis on these flow velocity patterns. METHODS: We examined 24 LITAs within 1 month (7 to 30 days) after surgery with a Doppler-tipped guide wire at the proximal, mid, and distal segments. Maximum peak velocities (MPV), time averaged peak velocities (APV), and velocity-time integrals (VTI) were measured. RESULTS: In LITAs without stenosis (n = 14, group A), the APV, MPV, and VTI values at the diastole were significantly greater than those for distal stenosis (minimal lumen diameter >75%, n = 10, group B). The values of the 3 indexes at the systole in each segment did not differ significantly between the 2 groups. Both groups showed gradual increases in the diastolic/systolic ratios of the 3 indexes from the proximal to distal portions, the ratios in group A being significantly larger than that in group B (APV, P <. 001; MPV, P <.01; TVI, P <.01, respectively). For these indexes, sensitivity and specificity for predicting stenosis of LITA was higher in the proximal and mid portion than in the distal. CONCLUSIONS: Anastomotic stenosis decreases the diastolic flow component but not the systolic one. By using diastolic/systolic ratios of the 3 indexes, it is possible to predict distal stenosis of LITA from the resting phasic flow velocity pattern.

Plasma alpha-tocopherol and coronary endothelium-dependent vasodilator function.

BACKGROUND: In the presence of atherosclerosis, the coronary endothelial vasomotor response to acetylcholine is frequently abnormal but is variable between patients. We tested the hypothesis that the plasma concentration of alpha-tocopherol is associated with the preservation of nitric oxide-mediated endothelium-dependent vasomotion. METHODS AND RESULTS: We studied 15 men and 6 women (mean age 61+/-10 years) at coronary angiography who were not taking vitamin supplements. Coronary endothelium-dependent and -independent vasomotion was assessed by intracoronary infusions of acetylcholine and nitroglycerin. The vasomotor responses were compared with the plasma concentration of alpha-tocopherol and the plasma alpha-tocopherol concentration relative to total lipid (total cholesterol plus triglycerides). The mean plasma alpha-tocopherol was 25.6+/-6.1 micromol/L, total cholesterol 193+/-27 mg/dL, triglycerides 115+/-66 mg/dL, and alpha-tocopherol to total lipid 4. 2+/-0.9 micromol. L(-1). (mmol/L)(-1). The mean vasomotor response to acetylcholine was -1% (range -33% to 28%) and to nitroglycerin 22% (range 0% to 54%). Plasma alpha-tocopherol was significantly correlated with the acetylcholine response (r=0.49, P<0.05) but not the nitroglycerin response (r=0.13, P>0.05). The acetylcholine response remained significant after adjustment for other potential sources of oxidant stress (total cholesterol, diabetes mellitus, smoking, angina class) (P<0.01). The relative concentration of alpha-tocopherol to total lipid was not related to endothelial function (r=0.24, P=0.3, n=20). CONCLUSIONS: alpha-Tocopherol may preserve endothelial vasomotor function in patients with coronary atherosclerosis. This effect may be related primarily to the action of alpha-tocopherol in the vascular wall. Further studies that assess the impact of alpha-tocopherol supplementation as therapy of endothelial dysfunction are justified.

Transgene expression and repression in transgenic rats bearing the phosphoenolpyruvate carboxykinase-simian virus 40 T antigen or the phosphoenolpyruvate carboxykinase-transforming growth factor-alpha constructs.

Transgenic Sprague-Dawley rats expressing either human transforming growth factor-alpha (TGFalpha) or simian virus 40 large and small T antigen (TAg), each under the control of the phosphoenolpyruvate carboxykinase (PEPCK) promoter, were developed as an approach to the study of the promotion of hepatocarcinogenesis in the presence of a transgene regulatable by diet and/or hormones. Five lines of PEPCK-TGFalpha transgenic rats were established, each genetic line containing from one to several copies of the transgene per haploid genome. Two PEPCK-TAg transgenic founder rats were obtained, each with multiple copies of the transgene. Expression of the transgene was undetectable in the TGFalpha transgenic rats and could not be induced when the animals were placed on a high-protein, low-carbohydrate diet. The transgene was found to be highly methylated in all of these lines. No pathological alterations in the liver and intestine were observed at any time (up to 2 years) during the lives of these rats. One line of transgenic rats expressing the PEPCK-TAg transgene developed pancreatic islet cell hyperplasias and carcinomas, with few normal islets evident in the pancreas. This transgene is integrated as a hypomethylated tandem array of 10 to 12 copies on chromosome 8q11. Expression of large T antigen is highest in pancreatic neoplasms, but is also detectable in the normal brain, kidney, and liver. Mortality is most rapid in males, starting at 5 months of age and reaching 100% by 8 months. Morphologically, islet cell differentiation in the tumors ranges from poor to well differentiated, with regions of necrosis and fibrosis. Spontaneous metastasis of TAg-positive tumor cells to regional lymph nodes was observed. These studies indicate the importance of DNA methylation in the repression of specific transgenes in the rat. However, the expression of the PEPCK-TAg induces neoplastic transformation in islet cells, probably late in neuroendocrine cell differentiation. T antigen expression during neoplastic development may result in a pervasive change in the islet cell growth properties with selection of a transformed phenotype as a possible requirement for cell viability.

Frequency domain heart rate variability and plasma norepinephrine level in the coronary sinus during handgrip exercise.

BACKGROUND: Heart rate (HR) variability has been recognized as an important noninvasive index of autonomic nervous activities. However, the relationship between HR variability and cardiac circulating norepinephrine (NE), especially with respect to coronary ischemia, remains unclear. HYPOTHESIS: This study was undertaken to determine whether HR variability indices can reflect cardiac NE levels during handgrip exercise. METHODS: We simultaneously measured HR variability and cardiac NE overflow rate in 32 patients (30 men, 2 women) during a 6-min isometric handgrip exercise. Among the 32 subjects, 20 (19 men, 1 woman) had coronary artery disease (CAD) and 12 (control group; 11 men, 1 woman) did not. RESULTS: Hemodynamics and cardiac NE overflow rates among subjects at rest were not significantly different between the two groups. In the normal subjects, low-frequency (LF) spectra and LF/HF (high-frequency) ratios were not significantly changed during handgrip exercise, but HF spectra significantly increased from 10.1 +/- 4.5 to 12.2 +/- 7.0 ms (p < 0.05). In the subjects with CAD, LF and LF/HF spectra were significantly (p < 0.05 and 0.01, respectively) increased by handgrip exercise. High-frequency spectra were not significantly changed by handgrip exercise. In the normal subjects, a significant negative relation (r = -0.76, p < 0.01) was obtained between HF change and cardiac NE overflow rate, whereas this relationship was not significant in the subjects with CAD. The correlation between changes of LF/HF and cardiac NE overflow rate was significant in the normal (r = 0.56, p < 0.05) but not in subjects with CAD. CONCLUSION: These results suggest that vagal modulation of HR variability is more prominent in normal coronary artery subjects than in CAD subjects during handgrip exercise. Heart rate variability indices may thus serve as adequate indicators of autonomic nerve activity in subjects with normal coronary arteries but not in those with CAD, probably due to decreased adaptation to physical stress during handgrip exercise.

Short-term fasting and the reversal of the stage of promotion in rat hepatocarcinogenesis: role of cell replication, apoptosis, and gene expression.

Studies of the multistage nature of hepatocarcinogenesis in the rat have led to the development of models having significant potential application to carcinogenesis in other tissues as well as other species. Whereas the initial and final stages of carcinogenesis-initiation and progression-involve genetic changes and are operationally irreversible, the intermediate stage of promotion is operationally reversible and can be modulated by a variety of environmental factors. Numerous investigations have demonstrated that chronic caloric restriction modifies neoplastic development, primarily during the stage of promotion, so that fewer lesions develop. Short-term fasting of rats, initiated with a nonnecrogenic dose of diethylnitrosamine (DEN) and promoted with 0.05% phenobarbital (PB) for 4 weeks, results in loss of virtually all of the measurable altered hepatic foci (AHF) after two 5-day periods of fasting with an intermediate 2-day period of feeding. This change was accompanied by a marked decrease in bromodeoxyuridine (BrdU) labeling of hepatocytes within AHF together with a significant increase in apoptosis of such cells measured by nick end-labeling. Similar but lesser effects were noted in surrounding, nonfocal hepatocytes. On refeeding, both the numbers and volume percentage of AHF returned within 2 weeks to values seen in nonfasted controls. Administration of PB during the fasting period did not alter these results, although AHF reappeared more rapidly in such animals on refeeding. Nuclear DNA fragmentation was evident in samples of whole liver from fasted animals. During this same period the expression of c-myc mRNA increased 3- to 9-fold, while levels of albumin and insulin-like growth factor I mRNAs decreased significantly. This study demonstrates a model system in which the reversibility of the effects of promoting agents may be rapidly determined and the effects of chemopreventive inhibitors of promotion may be rapidly evaluated.

Differences in heart rate variability in the acute phase of first and second attacks of myocardial infarction.

The purpose of the study was to examine the differences between first and second myocardial infarctions with respect to improvement in measures of heart rate variability (HRV). The study population comprised 48 non-diabetic patients with acute myocardial infarction (AMI), and with angiographically documented coronary artery occlusion and successful reperfusion. The subjects were grouped as 35 cases with a first AMI attack and 13 with their second AMI. Two weeks after the onset of infarction, indices of HRV were higher in first infarction cases than in second infarction cases. In the latter, there were no significant increases in HRV indices from day of onset to 2 weeks later, nor were there any significant changes in left ventricular ejection fraction (LVEF) from onset to 3 weeks later. All patients studied had a patent infarct-related artery 3 weeks later. We found sustained low values of HRV after a second AMI. Different risk stratification may be needed between uncomplicated first AMI and second AMI cases.

The effect of short-term fasting, phenobarbital and refeeding on apoptotic loss, cell replication and gene expression in rat liver during the promotion stage.

Previous work from this laboratory has reported on the effects of two sequential 5 day periods of fasting and subsequent refeeding on tumor promotion in multistage hepatocarcinogenesis in the rat (Carcinogenesis, 18, 159-166, 1997). In the present extension of the earlier study, the sequential fasting-refeeding regimen was begun at later time points (28 and 54 days post-initiation) than the first study. This was done to determine whether larger-sized altered hepatic foci (AHF) exhibited a depletion similar to that of the relatively small AHF in the published experiment and to study concomitant molecular changes during the fasting periods. Groups of animals were fasted in the presence and absence of 0.05% phenobarbital (PB) in the drinking water. During the fasting periods, both body and liver weights decreased dramatically, less in the fast begun at 54 days. This change was accompanied by a significant decrease in the bromodeoxyuridine (BrdU) labeling indices of hepatocytes within AHF. Apoptotic bodies increased dramatically in the non-focal (surrounding the AHF) hepatocytes during the fasting periods. These parameters were slightly lower in hepatocytes of rats administered PB during the fasting periods, most notably during the 54-66 day period. With the nick end-labeling method, the proportion of hepatocytes undergoing apoptosis was significantly higher in cells within AHF at the end of each of the fasting periods in all but one group. Concomitantly, the number of AHF and percentage of liver volume occupied by AHF decreased dramatically during the fasting periods. Refeeding caused a marked increase in BrdU labeling in hepatocytes within and surrounding AHF during the first week or two, most notably in animals not receiving PB during the fasting period. Both the number and volume percentage of liver AHF returned to control values within approximately 2 weeks of the refeeding regimen. Assays of nuclear DNA fragmentation with samples of whole liver indicated that a 'laddering' effect was most noticeable in livers of animals subjected to the fasting-refeeding regimen when phenobarbital was not present during the fasting period. Studies of the levels of mRNA of several genes in the total liver revealed that the expression of c-myc increased 3- to 9-fold during the fasting periods but rapidly returned to normal levels after refeeding. Levels of albumin and insulin-like growth factor I mRNAs decreased significantly during the fasting period, but rapidly reappeared on refeeding. These results indicate that the extensive loss of AHF during the short-term fasting periods occurs even when the number and volume of AHF are 10- to 50-fold greater at the beginning of the fast than the values published previously. Both the decrease in insulin growth factor I and the elevation of c-myc expression during the fasting period may indicate the role of these genes in the transcriptional regulation of hepatocyte apoptosis in both normal and preneoplastic hepatocytes in the rat.

Emergent Z stent placement for treatment of cor pulmonale due to pulmonary emboli after failed lytic treatment: technical considerations.

A patient with a pulmonary embolism due to deep vein thrombosis of a lower extremity developed hypotension and cor pulmonale despite prior placement of an inferior vena caval filter and treatment with a thrombolytic agent. After failure of percutaneous guidewire fragmentation and thrombosuction, self-expandable bilateral Z stents were positioned into the lower branches through the pulmonary arterial trunks. The patient experienced immediate relief of her cor pulmonale and successful recovery from hypotension.

Extent of ischemic stimulus and plasma beta-endorphin levels in silent myocardial ischemia.

BACKGROUND: Beta-endorphin has been reported to play a role in the mechanism of silent myocardial ischemia. OBJECTIVES: Plasma beta-endorphin levels during coronary angioplasty-induced silent and symptomatic myocardial ischemia were compared with those during exercise-induced silent ischemia. METHODS AND RESULTS: The study population consisted of 40 nondiabetic patients with angioplasty-indicated coronary artery disease. All patients underwent exercise treadmill testing 2 to 4 days before angioplasty. Patients were divided into three groups: group 1, 10 patients with silent ischemia during exercise and angioplasty; group 2, 15 patients with silent ischemia during exercise and symptomatic ischemia during angioplasty; and group 3, 15 patients with symptomatic ischemia during both exercise and angioplasty. In group 1, plasma beta-endorphin levels during balloon inflation were significantly higher than in groups 2 and 3 and also significantly higher than during exercise. In group 2, plasma beta-endorphin levels were significantly elevated at exercise-induced silent myocardial ischemia and balloon-induced symptomatic myocardial ischemia, but the levels between exercise and balloon inflation were not significantly different. CONCLUSIONS: For "silent" myocardial ischemia, it may be necessary for beta-endorphin levels to increase to sufficiently high levels to suppress anginal symptoms in response to the degree of ischemic stimuli.