Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038002 (splenomegaly)
 9,873 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

2-Deoxy-D-galactose, in a dose of 3 mmol/kg, was administered intraperitoneally twice daily to young rats for periods up to 12 weeks. This dosage schedule resulted in recurrent phosphate trapping predominantly in liver. UTP deficiency was excluded by simultaneous uridine injections. Phosphate trapping was caused by the rapid accumulation of 2-deoxy-D-galactose 1-phosphate and was most pronounced in liver but also demonstrated in small intestine, brain, spleen, and thymus. The marked, although transient, drop in the hepatic content of inorganic phosphate triggered the catabolism of adenine nucleotides and a loss of ATP. Other metabolic pathways affected by phosphate deficiency include glycogenolysis and glycolysis. Increasing with time, repeated doses of the galactose analog led to retardation and arrest of growth, hepatomegaly, and splenomegaly. The average relative liver and spleen weights were elevated 2.5- and 4.5-fold, respectively, after 12 weeks of treatment. Liver damage was indicated by hyperbilirubinaemia and a progressive rise in the activity in plasma of sorbitol dehydrogenase, alkaline phosphatase, and gamma-glutamyltransferase. Examination by light and electron microscopy showed increasing numbers of vacuoles, surrounded by a single membrane, in hepatocytes, sinusoidal endothelial cells, and Kupffer cells. Focal cytoplasmic degeneration in hepatocytes was occasionally indicated by formation of autophagic vacuoles and finger print lysosomes. Hepatocytes of 2-deoxy-D-galactose-treated rats showed a dissociation and fragmentation of the rough endoplasmic reticulum. Sinusoidal endothelial cells and Kupffer cells were markedly enlarged, the latter contained a PAS-positive but amylase resistant substance. Extrahepatic changes included an increased occurrence of vacuolated cells in thymus. Phosphate trapping and its metabolic consequences are common phenomena in the experimental injury induced b 2-deoxy-D-galactose and in some hereditary diseases such as uridylyltransferase deficiency galactosaemia, fructose intolerance and glucose-6-phosphatase deficiency.
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PMID:Consequences of recurrent phosphate trapping induced by repeated injections of 2-deoxy-D-galactose. Biochemical and morphological studies in rats. 4 10

Two patients with portal hypertension following chronic exposure to vinyl chloride monomer were studied histologically and ultrastructurally. Both cases showed non-cirrhotic portal hypertension accompanied by esophageal varices and splenomegaly. They proved hepatic fibrosis with conventional microscope. Ultrastructurally, there were large amounts of small myelin-like lamellar materials with electron density and remarkable proliferation and vesiculation of smooth endoplasmic reticulum in the cytoplasms of hepatocytes. The widened Disse's spaces, were the sinusoidal lining cells were arranged in multilayers, were plugged by collagenous fiber bundles. The finding may be consistent with the development of portal hypertension.
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PMID:Electron microscopic observation of the liver in portal hypertension following chronic exposure to vinyl chloride monomer. 89 37

Lysinuric protein intolerance (LPI), an autosomal recessive defect of diamino acid transport, is characterized chemically by renal hyperdiaminoaciduria, especially lysinuria, and by impaired formation of urea with hyperammonemia after protein ingestion. Our 20 patients thrived during breast-feeding, but ingestion of cow's milk caused diarrhea and vomiting. When able to select their diet, they rejected all protein-rich foods. They were short staturated and had weak atrophic muscles, osteoporosis, hepatomegaly and often splenomegaly. Four patients were mentally retarded. Fifteen patients had leukocyte counts below 4,000/mm3, and 17 patients had platelet counts below 150,000/mm3. Serum lactate dehydrogenase activity was constantly increased, and transaminase and aldolase activities were often increased. In the infants' livers, changes were only revealed by electron microscopy: increased and vesicular smooth endoplasmic reticulum, and abundance of glycogen particles in the hepatocytes. In the older patients, light microscopy demonstrated clearly limited areas where hepatocytes had large pale cytoplasm and small pyknotic nuclei. The diamino acids lysine, arginine and ornithine had plasma concentrations only one-third to one-half the normal mean; the renal clearances were clearly increased. Oral diamino acid loading tests suggested impaired intestinal absorption. Urea is built in the liver through transformation of ornithine to arginine, and cleavage of arginine to ornithine and urea. The addition of ornithine to an intravenous I-alanine loading prevented the hyperammonemia and normalized the urea production. Therefore, the diet has been supplemented with arginine, and more protein has been added. This therapy has lead to a remarkable catch-up growth in some patients. The pathophysiology of LPI is explained. Because of defective intestinal absorption and incrased renal loss, the diamino acids have a low plasma concentration. Their transport from plasma to hepatocytes is also impaired, and the liver becomes deficient in ornithine. This retards the urea cycle, and leads to postprandial hyperammonemia and protein aversion. The presence of the transport defect in the hepatocytes distinguishes LPI from other hyperdibasicaminoacidurias.
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PMID:Lysinuric protein intolerance. 115 80

A daily dose of 3 x 10(6) or 6 x 10(6) units of alpha-interferon was given during two 4- to 6-month periods to a 65-yr-old male patient with hairy cell leukemia, reducing splenomegaly and decreasing the number of hairy cells. Liver biopsy specimens taken during treatment revealed predominantly decreased hairy cell infiltration in the dilated sinusoids and enlarged or vacuolar nuclei of hepatocytes, compared with those in the liver before treatment. The ultrastructure of hepatocytes in specimens taken during treatment showed cytoplasmic vacuoles, weakly stained glycogen particles, and conspicuously decreased endoplasmic reticulum. Liver tests revealed decreased serum cholinesterase and total cholesterol levels in the early stage of treatment, low levels of total protein and albumin during treatment, and a very low value in the [13C]aminopyrine breath test. No clinical reports have been made on the decreased microsomal function during treatment with interferon. alpha-Interferon damaged the endoplasmic reticulum of hepatocytes, although it was effective for the reduction of hairy cells in the liver of hairy cell leukemia.
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PMID:The effect of alpha-interferon on the liver in a patient with hairy cell leukemia: light and electron microscopic studies. 275 86

An autopsy case of alpha-chain disease (ACD) clinically manifesting generalized lymph node swelling, slight splenomegaly and long-standing ichthyosiform skin eruptions, was reported. Autopsy revealed systemic superficial and profound lymph node swelling and slight splenomegaly, but little or no tumorous lesion in any part of the alimentary tract or pulmonary tissue. The histologic picture of the lymph nodes showed a diffuse monomorphic plasmocytic lymphoma, and there was tumor cell infiltration in the spleen and bone marrow. Immunohistochemistry demonstrated that the tumor cells contained IgA devoid of light chains, i.e. ACD protein. Immunoelectron microscopy revealed that this abnormal immunoglobulin was localized in the rough endoplasmic reticulum and perinuclear space. Persistent chronic inflammation with infiltration mainly of helper-inducer T cells were found in the skin and dermatopathic lymphadenopathy was confirmed in the lymph node biopsies. From these peculiar clinicopathological features, this case is considered to be a previously unknown form of ACD.
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PMID:A new form of alpha-chain disease with generalized lymph node involvement. 322 74

Hairy-cell leukemia is characterized clinically in splenomegaly and pancytopenia and pathologically by the proliferation in hematopoietic tissue of cells containing the tartrate-resistant isozyme 5 of acid phosphatase. We have described a patient with a T-lymphocyte variant of this disease. A permanent cell line obtained from the spleen of this patient has the biological and enzymatic characteristics of the fresh leukemic cells. We have used this line to study the surface morphology, ultrastructure, and ultrastructural localization of acid phosphatase in defined T-lymphoid hairy cells. The surface of the cells of the permanent line was smooth but many hair-like projections appeared after exposure to phytohemagglutinin (PHA). There was little acid phosphatase reaction produce visualized when beta-glycerophosphate was used as a substrate. With sodium haphthol AS-BI phosphoric acid heavy deposits were seen in the perinuclear membrane, mitochondria, and rough endoplasmic reticulum. Exposure to PHA and pokeweed mitogen resulted in increased reaction product, suggesting increased enzyme synthesis. Tartrate-resistant acid phosphatase was localized in the same organelles.
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PMID:Ultrastruct and tartrate-resistant acid phosphatase localization in a T-cell hairy-cell leukemia cell line. 696 46

Recent evidence suggests that interactions between spleen focus-forming virus (SFFV) env products and the erythropoietin receptor (EpoR) are responsible for viral pathogenicity. Infection of factor-dependent cell lines expressing epoR (the cloned gene for EpoR) with SFFVP is mitogenic, generating cell lines that are no longer dependent on added growth factor, and an immunoprecipitable complex between EpoR and immature env protein in the endoplasmic reticulum has been identified. The dependence of these in vitro activities on env protein processing and their relationship to pathogenicity of SFFV were explored by using glycosylation site mutants of SFFV env. Mutants carrying Asn-->Asp mutations at each of the two consensus signals for N-linked glycosylation in the N-terminal domain of SFFVAP-L env (gs1 and gs2), the gs1-2- double mutant, and the gs0 quadruple mutant (mutated at all four signals utilized for N-linked glycosylation in SFFVAP-L env) were made. The primary translation products (gp52) of single-site mutant envs were processed into more highly glycosylated forms, and the corresponding viruses induced splenomegaly in susceptible mice, whereas the gs1-2- and gs0 proteins were not processed, and these viruses were not pathogenic. Unprocessed env proteins of both pathogenic and nonpathogenic mutants coprecipitated with EpoR. In the BaF3 cell assay for epoR-dependent mitogenicity, the pathogenic single mutants induced factor-independent growth efficiently whereas the nonpathogenic gs1-2- and gs0 mutants did not. These data demonstrate that the ability of gp52 to form complexes with EpoR in the endoplasmic reticulum is not sufficient for either mitogenicity in cell culture or induction of splenomegaly in mice while supporting the hypothesis that pathogenicity and mitogenicity of SFFV both result from an interaction between EpoR and SFFV env protein.
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PMID:Erythropoietin receptor (EpoR)-dependent mitogenicity of spleen focus-forming virus correlates with viral pathogenicity and processing of env protein but not with formation of gp52-EpoR complexes in the endoplasmic reticulum. 843 18

We report about a 58-year-old female with coexisting type-I Gaucher's disease (GD) and multiple myeloma (MM). The diagnosis of GD was made in early childhood by means of bone marrow biopsy and was recently confirmed by analysis of the patient's genomic DNA for the underlying glucocerebrosidase mutations and the identification of the 1226G/1448C genotype. At the age of 24 years, the patient developed massive splenomegaly. Therefore, a splenectomy was performed. No further therapy was necessary for the next 34 years until 1999 when progressive anemia and thrombocytopenia occurred. Additional laboratory analysis revealed high serum protein and immunoglobulin (Ig) G levels and evidence of monoclonal gammopathy and lambda light-chain proteinuria, indicating plasma cell dyscrasia. This diagnosis was confirmed by the detection of osteolytic lesions in skeletal X-rays and a bone marrow biopsy showing an extensive infiltration with Gaucher cells and an increase of plasma cells, which expressed lambda light chains. When examined by means of electron microscopy, typical Gaucher cells, i.e., histiocytes containing tubular-structured cytoplasmatic material and spots of plasma cells with an increase of the endoplasmic reticulum, were found. GD associated with acquired MM has been described 13 times in the literature from 1968 to 1997. Only three of the patients were suffering from IgG myeloma. This distribution of the monoclonal component is in contrast to that of patients suffering from MM alone.
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PMID:Coincidence of Gaucher's disease due to a 1226G/1448C mutation and of an immunoglobulin G lambda multiple myeloma with Bence-Jones proteinuria. 1113 25

The maturation of N-glycans to complex type structures on cellular and secreted proteins is essential for the roles that these structures play in cell adhesion and recognition events in metazoan organisms. Critical steps in the biosynthetic pathway leading from high mannose to complex structures include the trimming of mannose residues by processing mannosidases in the endoplasmic reticulum (ER) and Golgi complex. These exo-mannosidases comprise two separate families of enzymes that are distinguished by enzymatic characteristics and sequence similarity. Members of the Class 2 mannosidase family (glycosylhydrolase family 38) include enzymes involved in trimming reactions in N-glycan maturation in the Golgi complex (Golgi mannosidase II) as well as catabolic enzymes in lysosomes and cytosol. Studies on the biological roles of complex type N-glycans have employed a variety of strategies including the treatment of cells with glycosidase inhibitors, characterization of human patients with enzymatic defects in processing enzymes, and generation of mouse models for the enzyme deficiency by selective gene disruption approaches. Corresponding studies on Golgi mannosidase II have employed swainsonine, an alkaloid natural plant product that causes "locoism", a phenocopy of the lysosomal storage disease, alpha-mannosidosis, as a result of the additional targeting of the broad-specificity lysosomal mannosidase by this compound. The human deficiency in Golgi mannosidase II is characterized by congenital dyserythropoietic anemia with splenomegaly and various additional abnormalities and complications. Mouse models for Golgi mannosidase II deficiency recapitulate many of the pathological features of the human disease and confirm that the unexpectedly mild effects of the enzyme deficiency result from a tissue-specific and glycoprotein substrate-specific alternate pathway for synthesis of complex N-glycans. In addition, the mutant mice develop symptoms of a systemic autoimmune disorder as a consequence of the altered glycosylation. This review will discuss the biochemical features of Golgi mannosidase II and the consequences of its deficiency in mammalian systems as a model for the effects of alterations in vertebrate N-glycan maturation during development.
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PMID:Golgi alpha-mannosidase II deficiency in vertebrate systems: implications for asparagine-linked oligosaccharide processing in mammals. 1241 4

Congenital dyserythropoietic anemias (CDAs) are phenotypically and genotypically heterogeneous diseases. CDA type II (CDAII) is the most frequent CDA. It is characterized by ineffective erythropoiesis and by the presence of bi- and multinucleated erythroblasts in bone marrow, with nuclei of equal size and DNA content, suggesting a cytokinesis disturbance. Other features of the peripheral red blood cells are protein and lipid dysglycosylation and endoplasmic reticulum double-membrane remnants. Development of other hematopoietic lineages is normal. Individuals with CDAII show progressive splenomegaly, gallstones and iron overload potentially with liver cirrhosis or cardiac failure. Here we show that the gene encoding the secretory COPII component SEC23B is mutated in CDAII. Short hairpin RNA (shRNA)-mediated suppression of SEC23B expression recapitulates the cytokinesis defect. Knockdown of zebrafish sec23b also leads to aberrant erythrocyte development. Our results provide in vivo evidence for SEC23B selectivity in erythroid differentiation and show that SEC23A and SEC23B, although highly related paralogous secretory COPII components, are nonredundant in erythrocyte maturation.
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PMID:Mutations affecting the secretory COPII coat component SEC23B cause congenital dyserythropoietic anemia type II. 1956 5


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