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Query: UMLS:C0023890 (cirrhosis)
 42,195 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Pulmonary hypertension is one of the major causes of morbidity and mortality of patients with sickle cell hemoglobinopathy (SCH). Although a clinically recognized complication of sickle cell disease (SCD), there are few published pathologic studies of pulmonary findings in these patients. The aim of this study was to define the pulmonary pathologic changes and to investigate correlation between the pathologic changes, the antemortem diagnosis of pulmonary hypertension, and the severity of SCH. Cases of SCH were identified from the autopsy database using Snomed codes. Clinical and echocardiograph data were collected for correlation with the pathologic data. A total of 20 adult patients (12 males and 8 females) were identified. Hemoglobin electrophoresis results were available for 16 patients, with hemoglobin S fraction percentages ranging from 23% to 97.8%. Eleven patients had SCD, 5 patients had sickle cell trait (SCT), and the remaining 4 patients without hemoglobin electrophoresis were included in the SCT group. The mean age of the SCT group was higher than that of the SCD group (P = 0.03). Histologically, all 20 patients demonstrated changes in pulmonary vasculature considered diagnostic of pulmonary hypertension grade I to grade IV, associated with plexiform lesions in 60% of patients. Medial hypertrophy and intimal hyperplasia/fibrosis, considered potentially reversible lesions, were seen in all patients. A weak association was found between SCD and plexiform lesions. Fibroelastic degeneration of small arteries, arterioles, and venules was identified in almost all (95%) cases. Clinically, tricuspid regurgitation was detected by echocardiogram in 10 of 20 (50%) patients; 6 of these 10 had significant regurgitation to allow estimation of systolic pressure. Sudden death occurred in 8 patients, with males having a significantly higher incidence. Cardiomegaly was present in 95% of patients, however, autosplenectomy and hepatic cirrhosis/hemochromatosis were observed almost exclusively in patients with SCD. Cirrhosis was found to have a strong positive association with SCD. This study demonstrates pulmonary hypertensive changes in all 20 autopsied patients who had SCH but died from various causes. We conclude that a high prevalence of pulmonary hypertension is associated with SCH with consequent high mortality. Therefore, patients with SCH would benefit from a regular periodic assessment for pulmonary hypertension regardless of age, sex, and severity of hemoglobinopathy.
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PMID:Pulmonary hypertension in sickle cell hemoglobinopathy: a clinicopathologic study of 20 cases. 1239 78

Our previous studies indicated that in the human paraventricular (PVN) and supraoptic (SON) nuclei, tyrosine hydroxylase (TH)--the first and rate-limiting enzyme in catecholamine synthesis--is localized mainly in magnocellular neurons and that antemortem factors regulate its expression. The purpose of the present study was to investigate the distribution of TH-immunoreactive (TH-IR) perikarya of the hypothalami of a large sample of well-documented adult subjects without neurological, psychiatric or endocrinological disease in order to identify factors that could regulate the expression of TH in the human neurosecretory neurons. Our material consisted of the hypothalami of 38 subjects studied immunohistochemically for TH using the peroxidase-antiperoxidase method. Striking individual differences were observed among the subjects studied concerning the number and distribution of TH-IR perikarya within the PVN and SON. These differences were evident throughout the entire rostrocaudal length of the hypothalamus and appeared to be related neither to the age or sex of the subjects nor to the postmortem interval or staining procedures. In the sample studied, a large number of TH-IR perikarya were observed specifically in all subjects that had suffered from right-sided heart failure due to pulmonary hypertension, liver cirrhosis or dehydration. In all the above illnesses, increased production and secretion of vasopressin (VP) are reported to occur due to a decrease in 'effective' blood volume or to osmotic stimulation. We conclude that somatic illnesses leading to prolonged osmotic or nonosmotic stimulation of VP release may induce increased expression of TH immunoreactivity in the human neurosecretory neurons related to neuronal activation.
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PMID:Increased expression of tyrosine hydroxylase immunoreactivity in paraventricular and supraoptic neurons in illnesses with prolonged osmotic or nonosmotic stimulation of vasopressin release. 1241 42

Chronic lung disease in humans is frequently complicated by the development of secondary pulmonary hypertension, which is associated with increased morbidity and mortality. Hypoxia, inflammation and increased shear stress are the primary stimuli although the exact pathways through which these initiating events lead to pulmonary hypertension remain to be completely elucidated. The increase in pulmonary vascular resistance is attributed, in part, to remodelling of the walls of resistance vessels. This consists of intimal, medial and adventitial hypertrophy, which can lead to encroachment into and reduction of the vascular lumen. In addition, it has been reported that there is a reduction in the number of blood vessels in the hypertensive lung, which could also contribute to increased vascular resistance. The pulmonary endothelium plays a key role in mediating and modulating these changes. These structural alterations in the pulmonary vasculature contrast sharply with the responses of the systemic vasculature to the same stimuli. In systemic organs, both hypoxia and inflammation cause angiogenesis. Furthermore, remodelling of the walls of resistance vessels is not observed in these conditions. Thus it has been generally stated that, in the adult pulmonary circulation, angiogenesis does not occur. Prompted by previous observations that chronic airway inflammation can lead to pulmonary vascular remodelling without hypertension, we have recently shown, using quantitative stereological techniques, that angiogenesis can occur in the adult pulmonary circulation. Pulmonary angiogenesis has also been reported in some other conditions including post-pneumonectomy lung growth, metastatic disease of the lung and in biliary cirrhosis. Such angiogenesis may serve to prevent or attenuate increased vascular resistance in lung disease. In view of these more recent data, the role of structural alterations in the pulmonary vasculature in the development of pulmonary hypertension should be carefully reconsidered.
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PMID:The structural basis of pulmonary hypertension in chronic lung disease: remodelling, rarefaction or angiogenesis? 1243 Sep 58

A patient with pulmonary hypertension and focal liver cirrhosis was hospitalized on the 12-th week of pregnancy because of threatened abortion and died after 2 days of hospital stay during which symptoms of portal and pulmonary hypertension progressed, decompensation of pulmonary heart and hepatic cellular insufficiency ensued and syndrome of disseminated intravascular coagulation developed.
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PMID:[Lethal outcome in a patient with pulmonary hypertension and liver cirrhosis on the 12-th week of pregnancy]. 1249 47

Osler-Weber-Rendu disease is a hereditary vascular disease with multiple manifestations. The liver is involved rarely. Vascular abnormalities include telangiectasis and arteriovenous fistulas, sometimes associated with fibrosis and cirrhosis. Hepatic arteriovenous shunting may include secondary portal hypertension, reduced liver function and high cardiac output. Two cases of Osler-Weber-Rendu disease with extensive hepatic arteriovenous fistulation were described in detail and we report on their clinical features. In the first patient, treatment was symptomatic since liver transplantation is not indicated because the patient was asymptomatic. Embolization treatment of hepatic arteries was indicated in the second patient because he had biliary disease and recurrent cholangitis secondary to vasculo-biliary shunts. Therapy with arterial embolization, banding, or ligature of hepatic arteries is still limited and provides unsatisfactory long-term results. Liver transplantation offers now another therapeutic option for patients with intrahepatic high shunting and secondary pulmonary hypertension.
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PMID:Intrahepatic Osler's disease: report of two cases and review of the literature. 1524 81

Urotensin-II (UII) is a highly potent endogenous peptide within the cardiovascular system. Through stimulation of Galphaq-coupled UT receptors, UII mediates contraction of vascular smooth muscle and endothelial-dependent vasorelaxation, and positive inotropy in human right atrium and ventricle. A pathogenic role of the UT receptor system is emerging in cardiovascular disease states, with evidence for up-regulation of the UT receptor system in patients with congestive heart failure (CHF), pulmonary hypertension, cirrhosis and portal hypertension, and chronic renal failure. In vitro and in vivo studies show that under pathophysiological conditions, UII might contribute to cardiomyocyte hypertrophy, extracellular matrix production, enhanced vasoconstriction, vascular smooth muscle cell hyperplasia, and endothelial cell hyper-permeability. Single nucleotide polymorphisms of the UII gene may also impart a genetic predisposition of patients to diabetes. Therefore, the UT receptor system is a potential therapeutic target in the treatment of cardiac, pulmonary, and renal diseases. UT receptor antagonists are currently being developed to prevent and/or reverse the effects of over-activated UT receptors by the endogenous ligand. This review describes UII peptide and converting enzymes, and UT receptors in the cardiovascular system, focusing on pathophysiological roles of UII in the heart and blood vessels.
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PMID:Emerging roles of urotensin-II in cardiovascular disease. 1546 91

Biliary cirrhosis in the rat triggers intrapulmonary vasodilatation and gas-exchange abnormalities that characterize the hepatopulmonary syndrome. This vasodilatation correlates with increased levels of pulmonary microcirculatory endothelial NO synthase (eNOS) and hepatic and plasma endothelin-1 (ET-1). Importantly, during cirrhosis, the pulmonary vascular responses to acute hypoxia are blunted. The purpose of this work was to examine the pulmonary vascular responses and adaptations to the combination of liver cirrhosis and chronic hypoxia (CH). In addition to hemodynamic measurements, we investigated whether pulmonary expression changes of eNOS, ET-1 and its receptors (endothelin A and B), or heme oxygenase 1 in experimental cirrhosis affect the development of hypoxic pulmonary hypertension. We induced cirrhosis in male Sprague-Dawley rats using common bile duct ligation (CBDL) and exposed them to CH (inspired PO2 approximately 76 Torr) or maintained them in Denver (Den, inspired PO2 approximately 122 Torr) for 3 wk. Our data show 1) CBDL-CH rats had a persistent blunted hypoxic pulmonary vasoconstriction similar to CBDL-Den; 2) the development of hypoxic pulmonary hypertension was completely prevented in the CBDL-CH rats, as indicated by normal pulmonary arterial pressure and lack of right ventricular hypertrophy and pulmonary arteriole remodeling; and 3) selective increases in expression of ET-1, pulmonary endothelin B receptor, eNOS, and heme oxygenase 1 are potential mechanisms of protection against hypoxic pulmonary hypertension in the CBDL-CH rats. These data demonstrate that unique and undefined hepatic-pulmonary interactions occur during liver cirrhosis and chronic hypoxia. Understanding these interactions may provide important information for the prevention and treatment of pulmonary hypertension.
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PMID:Hypoxic pulmonary hypertension is prevented in rats with common bile duct ligation. 1551 65

Portopulmonary hypertension is a complication of end-stage liver disease that adversely affects the outcome of liver transplantation (LT). We report a case of living related LT who developed severe pulmonary hypertension during and after LT. This 16-year-old girl suffered from biliary atresia, having undergone a portoenterostomy at 60 days of age, at the time of discovery of liver cirrhosis. She had been admitted to a local hospital several times for episodes of esophageal variceal bleeding. Neither dyspnea nor cyanosis was discerned until LT. Although pulmonary hypertension (PH) was disclosed by echocardiogram upon preoperative evaluation, we did not consider this a contraindication for LT, because the PH was mild. She underwent living LT from her father (graft volume/recipient body weight ratio: 0.99%). After induction of anesthesia for LT, a pulmonary flotation catheterization showed severe PH (>40 mm Hg). The pulmonary artery pressure continued to be elevated during surgery, although it was possible that her severe scoliosis affected the data. Hyperbilirubinemia was observed after LT, despite good liver function tests. On postoperative day 12, a portal vein thrombosis was detected requiring emergency thrombectomy and splenectomy. Her general condition worsened after the second surgery. She died due to cardiopulmonary failure. Autopsy showed marked hypertrophy of the right ventricle with intimal thickening in the pulmonary artery. In this case, the underestimated PH might have resulted in the unfortunate outcome. Before LT, PH should be carefully evaluated by measures including invasive assessment.
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PMID:Living related liver transplantation for biliary atresia with portopulmonary hypertension: case report. 1556 Dec 4

New developments in the epidemiology, treatment and prognosis of thalassemia have dramatically altered the approach to the care of affected patients, and these developments are likely to have an even greater impact in the next few years. Demographic changes have required an awareness and understanding of the unique features of thalassemia disorders that were previously uncommon in North America but are now seen more frequently in children and recognized more consistently in adults. New methods for measuring tissue iron accumulation and new drugs to remove excessive iron are advancing two of the most challenging areas in the management of thalassemia as well as other transfusion-dependent disorders. Improved survival of patients with thalassemia has given new importance to adult complications such as endocrinopathies and hepatitis that have a major impact on the quality of life. This chapter describes how these changes are redefining the clinical management of thalassemia. In Section I, Dr. Renzo Galanello describes recent advances in iron chelation therapy. Several new chelators are either licensed in some countries, are in clinical trials or are in the late stages of preclinical development. Some of these iron chelators, such as deferiprone (DFP) and ICL670, are orally active. Others, such as hydroxybenzyl-ethylenediamine-diacetic acid (HBED) and starch deferoxamine, require parenteral administration but may be effective with less frequent administration than is currently required for deferoxamine. Chelation therapy employing two chelators offers the possibility of more effective removal of iron without compromising safety or compliance. Other strategies for chelation therapy may take advantage of the ability of particular chelators to remove iron from specific target organs such as the heart and the liver. In Section II, Dr. Dudley Pennell addresses cardiac iron overload, the most frequent cause of death from chronic transfusion therapy. The cardiac complications related to excessive iron may result from long-term iron deposition in vulnerable areas or may be due to the more immediate effects of nontransferrin-bound iron. Cardiac disease is reversible in some patients with intensive iron chelation therapy, but identification of cardiac problems prior to the onset of serious arrhythmias or congestive heart failure has proven difficult. New methods using magnetic resonance imaging (MRI) have recently been developed to assess cardiac iron loading, and studies suggest a clinically useful relationship between the results using these techniques and critical measures of cardiac function. Measurements such as T2* may help guide chelation therapy in individual patients and may also enhance the assessment of new chelators in clinical trials. The use of MRI-based technology also holds promise for wider application of non-invasive assessment of cardiac iron in the management of patients with thalassemia. In Section III, Dr. Melody Cunningham describes some of the important complications of thalassemia that are emerging as patients survive into adulthood. Hepatitis C infection is present in the majority of patients older than 25 years. However, antiviral therapy in patients with thalassemia has been held back by the absence of large clinical trials and concern about ribavirin-induced hemolysis. More aggressive approaches to the treatment of hepatitis C may be particularly valuable because of the additive risks for cirrhosis and hepatocellular carcinoma that are posed by infection and iron overload. Thrombosis is recognized with increasing frequency as a significant complication of thalassemia major and thalassemia intermedia, and pulmonary hypertension is now the focus of intense study. Risk factors for thrombosis such as splenectomy are being identified and new approaches to anticoagulation are being initiated. Pregnancies in women with thalassemia are increasingly common with and without hormonal therapy, and require a better understanding of the risks of iron overload and cardiac disease in the mother and exposure of the fetus to iron chelators. In Section IV, Dr. Elliott Vichinsky describes the dramatic changes in the epidemiology of thalassemia in North America. Hemoglobin E-beta thalassemia is seen with increasing frequency and poses a particular challenge because of the wide variability in clinical severity. Some affected patients may require little or no intervention, while others need chronic transfusion therapy and may be appropriate candidates for hematopoietic stem cell transplantation. Enhancers of fetal hemoglobin production may have a unique role in Hb E-beta thalassemia since a modest increase in hemoglobin level may confer substantial clinical benefits. Alpha thalassemia is also being recognized with increasing frequency in North America, and newborn screening for Hemoglobin Barts in some states is leading to early detection of Hb H disease and Hb H Constant Spring. New data clarify the importance of distinguishing these two disorders because of the increased severity associated with Hb H Constant Spring. The use of intrauterine transfusions to sustain the viability of fetuses with homozygous alpha thalassemia has created a new population of patients with severe thalassemia and has raised new and complex issues in genetic counseling for parents with alpha thalassemia trait.
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PMID:Thalassemia. 1556 74

Pyrrolizidine alkaloids initiate disease in the lung (pulmonary hypertension), liver (veno-occlusive disease and cirrhosis), and kidneys (afferent arteriolar block and mesangiolysis) by inducing a megalocytotic phenotype in target endothelial and parenchymal cells. A "hit-and-run" type of exposure to the bioactive pyrrolizidine results, within 2-3 days, in enlarged cells with large nuclei and enlarged Golgi and endoplasmic reticulum, while the cells remain in G2/M block. In the present study, we recapitulated monocrotaline pyrrole (MCTP)-induced megalocytosis in cultures of bovine pulmonary arterial endothelial cells (PAEC), human Hep3B hepatocytes, human type II-like alveolar epithelial cells (A549), and human pulmonary arterial smooth muscle cells (PASMC) and investigated the subcellular mechanism involved. There was an inverse relationship between reduction in caveolin (Cav)-1 levels and stimulation of promitogenic STAT3 and ERK1/2 cell signaling. In megalocytotic PAEC, the Golgi scaffolding protein GM130 was shifted from membranes with heavy density to those with a lighter density. This lighter Golgi fraction was enriched for hypo-oligomeric Cav-1, indicating dysfunctional trafficking of cargo. Immunofluorescence imaging studies confirmed the trapping of Cav-1 in a GM130-positive Golgi compartment. There was an increase in Ser25 phosphorylation of GM130 (typically a prelude to Golgi fragmentation and mitosis) and increased association between pGM130, cdc2 kinase, and Cav-1. Nevertheless, megalocytotic MCTP-treated cells showed reduced entry into mitosis upon stimulation with 2-methoxyestradiol (2-ME), reduced 2-ME-induced Golgi fragmentation, and a slowing of Golgi reassembly after nocodazole-induced fragmentation. These data suggest that a disruption of the trafficking and mitosis sensor functions of the Golgi may represent the subcellular mechanism leading to MCTP-induced megalocytosis ("the Golgi blockade hypothesis").
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PMID:Monocrotaline pyrrole-induced endothelial cell megalocytosis involves a Golgi blockade mechanism. 1556 61


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