Epidemiology of delta hepatitis in Switzerland.
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Biomedical subjects
Publications and source records attributed to M Schmid.
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Eleven Y-specific DNA probes hybridizing with DNA from one or more 46,XX males were isolated from a recombinant phage DNA library constructed from flow sorted human Y chromosomes. Two probes hybridized with DNA from nine out of eleven, i.e. greater than 80% of these 46,XX males. The relative frequency of hybridization of the probes in the 46,XX males and in a 46,X,dic(Y) female, together with in situ hybridization data, allowed mapping of the probes on Yp in relation to a putative testis determining locus. Several of those probes were also absent in a 46,XY female, further refining a model for ordering the probes on Yp. The DNA of one XX male hybridized both with probes from Yp and probes from proximal Yq (excluding the pericentral region). This suggests that complex translocations may occur into the DNA of 46,XX males that involve not only parts of Yp but also parts of Yq.
Unlike hepatocellular hepatoma (HCC), the so-called fibrolamellar hepatoma (FLH) is found almost exclusively in the non-cirrhotic, non-infected liver. Patient characteristics and the course of the disease in FLH differ markedly from HCC. FLH represents only a small portion of hepatomas in general (approx. 2%), but accounts for over 40% of hepatomas in young adults. We present the case of a 38-year-old woman showing the typical histological findings of polygonal eosinophilic tumor cells and characteristic lamellar bundles of fibrous stroma, which led to the diagnosis of FLH. The approx. 140 cases of FLH published in the world literature are also presented and discussed. The usefulness of additional examinations (neurotensin, vitamin B12 binding capacity and copper stains) is mentioned. The difficulty in diagnosing FLH lies in its histological differentiation from focal nodular hyperplasia. When diagnosed early, however, FLH is characterized by good resectability with a chance of cure or at least a markedly better survival rate than HCC.
The estrogen and progesterone receptor content of liver cytosol was measured in female patients with focal nodular hyperplasia associated with oral contraceptive use and compared with the receptor content of non-tumorous liver and of primary hepatocellular carcinomas. Receptors were found in very low concentrations or were not measurable at all. In one case of focal nodular hyperplasia the estrogen receptor content of the tumor was higher than that in the adjacent normal liver. Malignant liver tumors and the male liver were characterized by a low or non-measurable receptor content. The study of nuclear receptors combined with the use of monoclonal antibodies may be more helpful in elucidating the complex relationship between oral contraceptive use, benign liver tumors and hepatic steroid receptors.
Unusual neurological symptoms were observed in three homosexual men in whom antibodies against HTLV-III were demonstrated. In case 1, with a known Kaposi sarcoma, multiple intracerebral space-occupying lesions with severe perifocal oedema resulted in marked focal neurological deficits. In case 2, there occurred a transitory myelopathic syndrome lasting a few days, followed by severe retinal changes, associated with a generalized cytomegalic infection, and a cerebrovascular accident in the brainstem. In case 3, a severe myositis especially of the shoulder girdle was diagnosed and treated one year before the demonstration of the HTLV-III infection. The pathogenetic relationship between these illnesses and the HTLV-III infection remains unexplained.
Seven cases of agranulocytosis and two of liver damage that were probably due to amodiaquine treatment were studied. In five cases agranulocytosis was combined with liver damage, and in one case of primary liver damage moderate neutropenia was present. Three patients died. High total doses or prolonged duration of treatment, or both, appear to favour the occurrence of these reactions. The clustering of five of the seven cases of agranulocytosis within six months in one medical centre indicates that the risk to benefit ratio of amodiaquine for malaria prophylaxis should be re-evaluated.
In order to study the influence of the colloid osmotic pressure on albumin and total liver protein synthesis, rat hepatocytes were isolated by collagenase perfusion and incubated in Krebs-Ringer-buffer for 4 h. The colloid osmotic pressure produced by different bovine serum albumin (BSA) or dextran 60 concentrations varied from 3 to 80 mm Hg. A physiological colloid osmotic pressure of 20 mm Hg was obtained with 5.7 g BSA or 3.7 g dextran 60 per 100 ml of buffer. Albumin synthesis was measured by Laurell rocket immunoelectrophoresis. Total liver protein and total secretory protein synthesis were determined by the measurement of 1-14C-leucine incorporation. Albumin synthesis was not primarily regulated by the colloid osmotic pressure as was demonstrated by a lack of inhibition after addition of BSA. There was no significant influence of the oncotic pressure on the incorporation of 14C-leucine into total liver proteins. The incorporation into total secretory proteins was inhibited by an increasing colloid osmotic pressure, mediated either by BSA or dextran, suggesting an inhibition of the secretion of plasma proteins other than albumin.
The rare fragile site at 16q22 was experimentally induced in lymphocyte cultures with various AT-specific, non-intercalating DNA-ligands. The optimum conditions for the induction of fra(16)(q22) were determined. The best expression of fra(16)(q22) was found with the aromatic diamidine berenil which is recommended for further studies on this fragile site. The results indicate that fra(16)(q22) is a region with AT-rich, late replicating DNA. The simultaneous treatment of lymphocytes with berenil and aphidicolin (inhibitor of DNA polymerase alpha) induces both the rare fra(16)(q22) and the common fra(16)(q23) within the same chromosome. A population study on 350 unselected individuals showed that fra(16)(q22) is the most common of all rare autosomal fragile sites in man. The frequency of individuals heterozygous for fra(16)(q22) is 5.1%, no homozygosity for fra(16)(q22) was detected. Statistical analysis indicates that the population is in Hardy-Weinberg equilibrium with respect to the fragile and non-fragile chromosomes 16.
A paracentric inversion (7)(q11q22) and mosaicism 46,XX/45,X was detected in a female with minor malformations. The same inversion was observed in the mother of the patient. The analysis of high resolution banded chromosomes revealed no visible imbalance in the inverted long arm of the chromosome 7. All published cases of paracentric inversions in the human chromosome 7 are reviewed and the relationship between this inversion and the occurrence of an aneuploidy of the sex chromosomes is discussed.
A case report of a de novo deletion in the short arm of chromosome 7 is presented (46,XX,del(7)(p21----pter)). The five-month-old girl's major symptoms are: trigonocephalus with craniosynostosis, median bony forehead bulge, high palate, atrial septal defect, anal atresia and perineal fistula, thumb insertion far to ulnar-proximal, and a slightly retarded psychomotor development. The other cases with monosomy 7p described in the literature are reviewed.
The deoxycytidine analogue 5-azadeoxycytidine (5-aza-dC) induces differential inhibition of sister chromatid condensation when cells are treated with this substance for two replication cycles, as the subsequent staining of metaphase chromosomes with Giemsa shows. The bifilarly substituted chromatid is dramatically longer than the unifilar one. A percentage of the metaphases treated with 5-aza-dC even show a complete undercondensation of the bifilarly substituted chromatid. The optimum conditions for inducing sister chromatid differentiation were determined. No method has been developed as yet to permit enhancement of the differential staining in 5-aza-dC-treated preparations. The interactions between 5-aza-dC and chromosomal DNA as well as the factors involved in the differential staining of sister chromatids are discussed.
The development of visual acuity and stereopsis was studied in 321 boys and 340 girls aged between 5 and 10 years. Visual acuity was assessed by the E test and a modified version of the STYCAR test, stereo acuity by the Lang-Stereo test [17]. Both vision tests showed an increase in the median visual acuity between the ages of 5 and 10 years. The E test indicated an increase from 1.2 between 5 and 6 years to 1.5-1.7 between 7 and 10 years. The values obtained with the STYCAR test were 0.6-1.3 higher, depending on the test rating used. Visual acuity norms between 5 and 10 years are presented as empirical centile curves. No significant differences were observed in visual acuity between the left and right eyes, nor between the sexes. The right eye was found to be the leading eye in 54.8% of the boys and 54.5% of the girls (P less than 0.001). The Lang-Stereo test was passed by 87.9%-94.3% of all children, and there were no significant differences with respect to age and sex. Children who failed the test had a significantly lower visual acuity than those who passed it. In the former group a significant interocular difference in visual acuity was present (P less than 0.01).
To date there is little information about hemorheological data in the presence of secondary risk factors. Inter- and intraindividual comparisons of hemorheological parameters show that fitness has a significant influence on blood fluidity as quantified by ex vivo measurements of blood and plasma viscosity, red cell filterability and red cell aggregation. In fitter individuals blood is more fluid. Similar observations can be made with stress. Prolonged psychoemotional stress leads to a loss in blood fluidity and red cell filterability. Finally a comparison between excessively obese patients and healthy controls reveals a deterioration in hemorheological parameters in the obese group. These results, together with reports from the literature suggest that all accepted cardiovascular risk factors are associated with abnormalities in the flow properties of blood. It is proposed that partly the same phenomena are involved in the genesis of atherosclerotic lesions and influence rheological properties of blood.
This paper presents a case of gonadal dysgenesia with an uncommon structural X-chromosome abnormality (45, X-46, X, ring X mosaicism). The ring chromosome was not derived from an Y-chromosome as excluded by Q-banded analysis. The phenotypic expression of this abnormality caused typical Turner stigmata such as short stature, dysmorphic feature, streak ovaries with hypergonadotropic condition.
A de novo supernumerary small marker chromosome 15 was observed in a female infant with mental and statomotoric retardation as well as minor facial dysmorphia. The marker chromosome was analyzed by ten different staining techniques and 5-azacytidine treatment of lymphocyte cultures. It is shown that the supernumerary chromosome was derived by a non-sister chromatid exchange between the two homologous maternal chromosomes 15. The cytogenetical properties of the marker chromosome, the different activity of its two nucleolus organizer regions and the somatic pairing configurations revealed by 5-azacyidine are reported.
The chromosomes of the gorilla were extensively studied with various staining techniques labeling the different classes of heterochromatin. The chromosomal distribution of distamycin A/DAPI-, D287/170-, quinacrine-, and chromomycin A3-positive heterochromatic regions, as well as the nucleolus organizer regions, is described and compared with the karyotypes of other hominoid species. Lymphocyte cultures were treated with low doses of 5-azacytidine during the last hours of culture. This cytidine analog induces distinct undercondensation in 37 heterochromatic regions in the 24 gorilla chromosomes. The 5-azacytidine-induced undercondensations are localized not only in most of the distamycin A/DAPI-bright heterochromatic regions but also in many telomeric C-bands of the chromosomes. Furthermore, 5-azacytidine preserves the somatic pairing between heterochromatic regions from the interphase nuclei into the metaphase stage. The homeologies and differences in the chromosomal localization of the various classes of heterochromatin, 5-azacytidine-sensitive regions, 5-methylcytosine-rich DNA sequences, and satellite DNAs in the gorilla, chimpanzee, orangutan, and man are discussed.
The karyotypes of the two hamster species Phodopus sungorus and P. roborovskii were analyzed with several banding techniques and compared. The homoeologies found between all chromosomes led to the proposal of the most likely common ancestral karyotype of these two species. The differences in the karyotypes were found to be a result of seven independent centric fusions, three inversions, and one possible telomeric fusion, as well as changes in the quantity and DNA-base pair composition of the constitutive heterochromatin.