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J de Groote

Publications and source records attributed to J de Groote.

At least 19 recordsLinked to original sources
PubMed1990

An exclusion map of Marfan syndrome.

The combined genetic data between the Marfan syndrome and 75 informative loci on 18 autosomes were used to construct an exclusion map for this disorder. Data are also presented for a further two unmapped markers. The most likely location of the Marfan syndrome gene is highlighted and all the unexcluded areas of the genome are displayed in a graphical form. This exclusion map shows that almost 75% of the genome has been excluded as a likely location for the Marfan syndrome gene in the majority of the families studied. Apart from chromosomes 8, 13, 21, and 22, for which no data were available, other regions not excluded yet include 5p, 6p, 9p, 10p, 12p, 15, 17p, 18, and 20p. Future linkage analysis using markers located in the highlighted regions should facilitate the identification of the site of the Marfan syndrome gene.

Chromosome Mapping↗
PubMed1990

Linkage data for Marfan syndrome and markers on chromosomes 1 and 11.

Six large families with classical Marfan syndrome were studied using markers on chromosomes 1 and 11. Two of three families tested showed negative scores using D1S7 but a third family gave a positive score (0.92) at theta = 0.1. The other chromosome 1 markers typed (MUCI, NGFB, D1S8) excluded close linkage. Negative lod scores with two chromosome 11q22 markers (D11S84, D11S148) excluded at least 20 cM in this area (Z = less than -2), which was chosen for study as two enzymes responsible for collagen degradation (collagenase and stromelysin) are localised to this region.

Chromosomes, Human, Pair 1↗
PubMed1987

Ulcerative colitis, primary sclerosing cholangitis, bile duct carcinoma, and generalized sarcoidosis. Report of a unique association.

We describe a young man with a hitherto unreported association of chronic ulcerative colitis, primary sclerosing cholangitis (PSC), bile duct carcinoma, and generalized sarcoidosis with features of high-intensity alveolitis. This finding suggests that common immunological mechanisms may be involved in the pathogenesis of these diseases.

Adenocarcinoma, Scirrhous↗
PubMed1985

Storage of alpha-1-antitrypsin in intrahepatic bile duct cells in alpha-1-antitrypsin deficiency (Pi Z phenotype).

Storage of alpha-1-antitrypsin (AAT) has been found in a small number of bile duct cells in liver tissue specimens from patients with Pi MZ, Pi SZ and Pi ZZ phenotypes. The storage appeared in the form of intracellular AAT immunoreactive inclusions. On EM investigation, AAT-like material was detected within cisternae of the RER and SER. Such AAT inclusions were found in proliferating bile ductules in conditions such as cirrhosis, focal nodular hyperplasia and extrahepatic obstruction. They were also observed in normal biliary structures at the level of the canals of Hering, bile ductules and interlobular ducts in 13 out of 47 cases. These findings are interpreted as indicating that the intrahepatic bile duct cells are a further source of AAT, and that in case of defective export of AAT from the cell, as is the case for the Z protein, the protein accumulates not only in hepatocytes but in biliary cells as well.

Bile Ducts, Intrahepatic↗
PubMed1984

Sclerotherapy of oesophageal varices after variceal haemorrhage.

Fifty-six patients with recent variceal haemorrhage were studied in a trial of repeated injection sclerotherapy through the flexible oesophagoscope, with a mean follow-up of 15.2 months (1-39). Twenty-five patients (45%) did not suffer further bleedings. The risk of bleeding per patient-month of follow-up decreased significantly (p less than 0.05) after starting therapy, in all groups of cirrhosis, classified according to Child's criteria. Mortality during the study period was 39% (19.6% due to recurrence of variceal bleeding). The main complications of the procedure were the development of oesophageal wall ulcerations and oesophageal stricture.

Adolescent↗
PubMed1984

Immunohistochemical characterization of inflammatory infiltrates in primary biliary cirrhosis.

Ten liver biopsy specimens from nine patients with PBC stages II to IV were studied immunohistochemically with a broad panel of monoclonal antibodies. In areas of bile-duct proliferation, many BA1+ B-lymphocytes and OKT4+/Leu3a+ helper/inducer T-cells were observed, admixed with some C3b-receptor positive, mono- and polymorphonuclear OKM1+ cells. Numerous IgM-containing plasma cells were seen in portal tracts showing bile-duct proliferation. In contrast, areas of piecemeal necrosis and intralobular spotty necrosis consisted mainly of OKT4+/Leu3a+ helper/inducer, and OKT8+ suppressor/cytotoxic T-cells, admixed with some OKM1+ polymorphonuclear granulocytes. Almost no BA1+ B-lymphocytes or Ig-containing plasma cells were observed in areas of piecemeal necrosis and spotty necrosis. Major histocompatibility complex (MHC)-class I antigens (i.e. HLA-A,B,C) were demonstrated either on the liver cell membrane, or on sinusoidal lining cells. The latter also expressed MHC-class II antigens (i.e. HLA-DR). In two liver biopsies, an increased expression of HLA antigens was observed near areas of piecemeal and spotty necrosis. Our results indicate that several immune mechanisms each with a particular topographical distribution, are operative in PBC. Inflammatory cells, involved in humoral immunity, are present mainly in areas of bile duct proliferation. In contrast, the effector cells of antigen-specific cellular cytotoxicity are present in areas of piecemeal necrosis and spotty necrosis. In the latter areas, a pronounced expression of MHC products representing the afferent limb of the cell-mediated immune response, may permit an optimal T-cell-mediated immune effect or, eventually, result in adverse effects.

Antibodies, Monoclonal↗
PubMed1984

Alpha-1-antitrypsin (AAT) and its stimulation in the liver of PiMZ phenotype individuals. A "recruitment-secretory block" ("R-SB") phenomenon.

PiMZ individuals in conditions of clinical stimulation show a peculiar immunohistochemical staining pattern for alpha-1-antitrypsin (AAT) in the liver: 1) the positivity involves large zones of parenchyma (up to 100% of hepatocytes); 2) in zone 2 and zone 3 hepatocytes the positivity appears in the form of crescents or rectilinear arrays along the sinusoids. This new pattern is designated type II, in contrast to type I which occurs in periportal hepatocytes in the form of inclusions spread over the whole cytoplasm. This peculiar staining pattern is associated with serum elevation of AAT and is considered to be an expression of liver reactivity. Type II positivity marks the hepatocytes which are newly recruited for the synthesis of AAT; owing to its defective export, the Z AAT is retained within the cell and detectable by immunohistochemistry. Thus this staining pattern is an expression of both recruitment for synthesis and block of secretion ("Recruitment-Secretory Block" "R-SB" phenomenon). In PiMZ individuals, the secretory block affects selectively and exclusively the Z fraction of AAT. At the EM level the vast majority of the retained protein is found in the RER, which represents the major and the earliest site of storage. Viewed in the framework of present knowledge of glycoprotein biosynthesis, the results of this study shed further light on the nature and cellular site of the Z AAT defect.

Biopsy↗
PubMed1983

Comparative histology of acute hepatitis B and non-A, non-B in Leuven and Padova.

A histological study was performed on liver biopsies from patients with acute hepatitis A (n = 13), B (n = 35) and non-A, non-B (nAnB) (n = 35) in search for microscopical features characteristic for each type of hepatitis. Biopsies from two centres (Padova, Italy and Leuven, Belgium) were studied in order to determine whether the histological pattern in acute hepatitis A, B and nAnB may differ from one centre to another. The histology of cases of hepatitis A and B from Italy and Belgium did not differ. Less liver cell plemorphism was found in hepatitis A than in B. Clear differences were observed between acute hepatitis nAnB occurring in Padova when compared with cases from Leuven. The Padova-biopsies obtained from patients with transfusion-induced viral hepatitis were mainly characterized by a high degree of lympho-histiocytic intrasinusoidal infiltration whereas the Leuven-biopsies, mostly taken in patients with sporadic hepatitis, were characterized by the presence of numerous acidophilic bodies and Mallory body-like cytoplasmic alterations. Morphologically, the latter cases appear to be closely related to hepatitis B.

Belgium↗
PubMed1983

Prognostic significance of piecemeal necrosis in acute viral hepatitis.

The predictive value of piecemeal necrosis (PMN) in acute hepatitis was investigated in 62 patients (39 hepatitis B virus infection, 9 hepatitis A virus infection and 14 possible hepatitis NANB virus infection). The 62 initial biopsies were blindly recoded and classified into three groups: 1. Acute hepatitis with signs of possible transition to chronicity (AHTC) (n = 35) (i.e. a picture of acute hepatitis associated with PMN). 2. AHTC-borderline group (BL) (n = 15) (i.e. a picture of acute hepatitis with minimal PMN). 3. Uncomplicated acute hepatitis (AH) (n = 12) (i.e. a picture of acute hepatitis without PMN). Follow-up of the patients revealed an evolution to chronicity in a very high percentage of the AHTC-cases of hepatitis B (95%) and NANB (89%) etiology. Also 67% of the BL-cases of hepatitis B etiology developed chronic liver disease. In hepatitis B the immunohistochemical pattern of HBsAg is of additional help. In hepatitis A, PMN is often present (5/9) but no evolution to chronicity was observed. This study shows that PMN in acute hepatitis appears to be a useful prognostic feature for chronicity in hepatitis B and NANB.

Acute Disease↗
PubMed1975

Ligandin.

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Animals↗