Semiautomated quantification of hepatitis B virus DNA in a routine diagnostic laboratory

The Cobas Amplicor HBV Monitor test for quantitative determination of hepatitis B virus (HBV) DNA in serum has recently been introduced. To evaluate the performance of this assay in a routine diagnostic laboratory, reproducibility of results was determined with the First European Union Concerted Action HBV Proficiency Panel and the Accurun 325 HBV DNA Positive Control, Series 300. Results for 270 routine serum samples were additionally evaluated. To avoid the retesting of a large number of samples due to titers exceeding the upper limit for the linear range of the assay, sera of patients with chronic hepatitis B (CHB) were diluted prior to the assay to 10(-4) in normal human plasma, which is included in the assay. The mean coefficient of variation was 22.9% for all input HBV DNAs. Of 270 routine serum samples, 182 (150 sera from transplant donors and 32 sera from patients who had recovered from CHB) tested negative. Eighty-six sera were found to be HBV DNA positive; in six sera, HBV DNA levels were found to exceed the upper limit for the linear range of the assay and had to be retested. In the remaining two sera, inhibition occurred. The semiautomated Cobas Amplicor HBV Monitor test showed sufficient reproducibility and helped in avoiding human error. The relatively narrow linear range of detection is a limitation of the new assay.     

A new form of skeletal dysplasia with amelogenesis imperfecta and platyspondyly

We report two patients, born of consanguineous parents, affected by a disorder resulting in mild growth retardation. Hallmarks are amelogenesis imperfecta (absence of the enamel cap) associated with brachyolmia-like anomalies: platyspondyly with short pedicles, narrow intervertebral and interpedicular distances, rectangular-shaped vertebrae with posterior scalloping and herniation of the nuclei, and broad femoral necks. Inheritance appears to be autosomal recessive.     

Non-A, non-B hepatitis in persistent carriers of hepatitis B virus

There are reports in the literature that infection with hepatitis A virus in hepatitis B carriers can result in resolution of the carrier state. In an attempt to induce clearance of the carrier state of hepatitis B virus in two persistently infected chimpanzees, the chimpanzees were infused with documented non-A, non-B infectious material. Biochemical and histopathological evidence of hepatitis was accompanied by the unique abnormalities of endoplasmic reticulum associated with non-A, non-B hepatitis in the chimpanzees. Elevation of alanine aminotransferase was accompanied by fourfold reduction in one chimpanzee and sixfold reduction in the other in the plasma levels of HBV-associated DNA polymerase activity and simultaneously by twofold reduction in the concentration of hepatitis B surface antigen in both chimpanzees. A mediator may account for these changes in markers of hepatitis B virus infection, and this mechanism may also explain the occurrence of spontaneous regression in some persistently infected carriers. The significance of transient red cell anaemia in non-A, non-B hepatitis, which was observed in one of the chimpanzees, is yet to be established.     

Monomères acryliques à fonction carbonate cyclique, 2 Modification chimique de copolymères à groupements carbonate cyclique lateraux

Acrylic monomers with a cyclic carbonate function, their synthesis having been described previously, are used to synthesize copolymers with pendent cyclic carbonate side groups. Their chemical modification by ring opening addition reactions provides a convenient method for preparing functional polymers. The study of reactions with amines, on model compounds and on polymers, shows the possibility of obtaining a macromolecular network with crosslinking groups of carbamate type.     

Lack of selective Vβ deletion in peripheral CD4+ T cells of human immunodeficiency virus-infected infants

To investigate the possibility of superantigen-mediated deletions of T cells expressing particular T cell receptor Vβ (TcR Vβ) gene segments during human immunodeficiency virus (HIV) infection, TcR Vp usage in CD4⁺ and CD8⁺ subsets was analyzed in a cohort of infants maternally infected by HIV and in a group of healthy neonates. We used a semi-quantitative anchored polymerase chain reaction technique together with cytofluorographic analysis with anti-Vβ monoclonal antibodies. The representation of the 24 vβ families in CD4⁺ and CD8⁺ T cells from normal neonates was very similar to that in adults. Preferential expression of Vβ2 in the CD4⁺ subset was observed in both the neonates and in healthy adults. The representation of the 24 Vβ families in peripheral CD4⁺ T cells from the HIV-infected infants showed no selective vβ deletion, even when the CD4⁺ subset was globally depleted. Moreover, the main characteristics of the control group (predominance of certain Vβ families and Vβ2 skewing towards the CD4⁺ subset) were also present in all the HIV-infected infants.     

Mantle cell lymphoma, in leukaemic phase with prominent splenomegaly. A report of eight cases with similar clinical presentation and aggressive outcome

Mantle cell lymphoma (MCL) is a well-defined peripheral B-cell lymphoma usually diagnosed upon peripheral lymph node biopsy. We report eight cases of peripheral B-cell leukaemia that demonstrate presumptive evidence of mantle cell characteristics. The patients had a median age of 68.5 years, and five were male. All presented with an enlarged spleen without any peripheral lymphadenopathies, and they were leukaemic at presentation (median lymphocytosis, 38x10(9)/l). Morphological diagnosis of MCL was very difficult in five cases but easier in three because we were able to analyse either pre- or post-mortem lymph nodes and spleen. The immunophenotype of blood lymphocytosis using flow cytometry, the presence of a t(11;14)(q13;q32) and a cyclin D1 expression by leukaemic cells all fit with the diagnosis of MCL. All patients progressed and died with a median overall survival of 8 months. Multifocal areas of transformation in blastoid or large cell variants were observed in the three autopsied patients. In summary, one should consider the diagnosis of MCL at presentation in leukaemic phase even in the absence of peripheral adenopathies.     

Study of a new strain of paramyxoviruses isolated from wild ducks: structural polypeptides.

By polyacrylamide gel electrophoresis, Duck/Mississippi/75 virus was shown to contain five different types of polypeptides of mol. wt. ranging from 76 X 1O(3) to 43 X 10(3), two of which were glycosylated (mol. wt. 76 X 10(3) and 57 X 10(3). A comparison of this data with similar results obtained using Yucaipa and Newcastle disease virus (NDV) revealed a similarity with NDV, concerning the number, position and mol. wt. of the polypeptides. Haemagglutinating and neuraminidase properties are associated with surface glycoproteins which represent at least 40% of the virus protein. After KCl and Triton X-100 treatment and centrifugation on linear sucrose density gradients (10 to 25%, w/w) it was possible to isolate glycoprotein VP1 of mol. wt 76 X 10(3) with which haemagglutinating and neuraminidase activities were associated.     

Genetic and light intensity effects on the activity and emigratory behavior of the house fly,Musca domestica (L.)

The emigratory behavior and locomotor activity of yellow-eyed (y/y), wildtype (+/+), and heterozygous (+/y) house flies was examined at 8 fc (86 lx) and 1600 fc (17,223 lx) light intenstities. At 8 fc, emigration rate and activity of the y/y flies was similar to that of the +/+ and +/y flies. However, at 1600 fc, the y/y flies emigrated at twice the rate and showed an activity of about one-third that of the other genotypes. The behavior of the +/+ and +/y flies remained similar regardless of the experimental design or light intensity. The excessive neural stimulation by high-intensity light resulting from reduced shielding pigments led to behavioral modifications in the visual and tactile responses of the y/y flies.This research was supported in part by grants from the CUNY Faculty Research Award Program (No. 1103) and NIH Biomedical Research Support Grant 5-S05-R-07064.