Analysis of a cellular model to account for the natural history of infection by the hepatitis B virus and its role in the development of primary hepatocellular carcinoma.

Infection with the hepatitis B virus (HBV) can have many different outcomes. Transient infection may result in acute hepatitis or may remain subclinical. Persistent infection may also be subclinical, or may involve chronic active hepatitis, and can finally lead to the development of primary hepatocellular carcinoma.

Human immunodeficiency virus type 1 nef quasispecies in pathological tissue.

The role of the nef gene in human immunodeficiency virus type 1 (HIV-1) infection is poorly understood. To provide a basis for studies on the role of nef in AIDS, we used targeted polymerase chain reaction amplification and DNA sequencing to determine the structure of nef genes in pathologic tissue from HIV-1-infected children and adults. We find that the nef reading frame is open in 92% of clones derived from both brain and lymphocytic tissue of children, suggesting that nef is expressed in these tissues.

Gastrulation in the mouse: the role of the homeobox gene goosecoid.

Mouse goosecoid is a homeobox gene expressed briefly during early gastrulation. Its mRNA accumulates as a patch on the side of the epiblast at the site where the primitive streak is first formed. goosecoid-expressing cells are then found at the anterior end of the developing primitive streak, and finally in the anteriormost mesoderm at the tip of the early mouse gastrula, a region that gives rise to the head process.

Human immunodeficiency virus type 1 infection of neural xenografts.

Human immunodeficiency virus type 1 (HIV-1) infection is highly specific for its human host. To study HIV-1 infection of the human nervous system, we have established a small animal model in which second-trimester (11 to 17.5 weeks) human fetal brain or neural retina is transplanted to the anterior chamber of the eye of immunosuppressed adult rats.

Usage and bioassays in Phyllanthus (Euphorbiaceae): a compilation. III. The subgenera Eriococcus, Conami, Gomphidium, Botryanthus, Xylophylla and Phyllanthodendron, and a complete list of the species cited in the three-part series.

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published in four papers, including (in Part IV) analysis, discussion and conclusions concerning apparent clustering of some uses or effects within taxa. This paper (Part III) covers the subgenera Eriococcus, Conami, Gomphidium, Botryanthus, Xylophylla and Phyllanthodendron, and also includes a list of the species cited in this three-part series.

Macrophage tropism determinants of human immunodeficiency virus type 1 in vivo.

Strains of human immunodeficiency virus type 1 differ in their abilities to infect and replicate in primary human macrophages. Chimeric clones were constructed from a provirus unable to infect macrophages (NLHX) and envelope sequences (V3 loop) of viruses derived without cultivation from brain (YU2 and w1-1c1) or spleen (w2-1b4) tissues. The substituted V3 loop sequences in each case were sufficient to confer upon NLHX the ability to infect macrophages.

Multiple retinoid-responsive receptors in a single cell: families of retinoid "X" receptors and retinoic acid receptors in the Xenopus egg.

In a search for nuclear hormone receptors expressed in early development we found that Xenopus laevis eggs contain mRNAs from two retinoic acid receptor genes (xRAR alpha and xRAR gamma) and two retinoid "X" receptor genes (xRXR alpha and xRXR gamma). We also show that RXRs are members of a family of at least three genes, thus expanding the number of genes encoding retinoic acid-responsive transcription factors to six. With the exception of xRXR gamma, these maternal mRNAs are degraded before gastrulation.

Hepatitis B x antigen and polymerase antibodies in the serum of hepatitis B carriers with or without hepatitis delta virus infection. Effects of interferon treatment.

Previous work has shown that the hepatitis B x antigen (HBxAg) and antibodies directed against the polymerase of hepatitis B virus (anti-pol) are early markers of hepatitis B virus (HBV) replication in natural infections. The present study was carried out to test the hypothesis that the appearance of one or both of these markers signaled reactivation in chronic carriers with liver disease who were treated with alpha-interferon (IFN). The results show that HBV DNA decreased among the patients who responded to therapy, and that among these responders, neither HBxAg nor anti-pol became detectable in serum for 12 months after treatment, in contrast to controls.

Molecular nature of Spemann's organizer: the role of the Xenopus homeobox gene goosecoid.

This study analyzes the function of the homeobox gene goosecoid in Xenopus development. First, we find that goosecoid mRNA distribution closely mimics the expected localization of organizer tissue in normal embryos as well as in those treated with LiCl and UV light. Second, goosecoid mRNA accumulation is induced by activin, even in the absence of protein synthesis.

Characteristics of hepatitis B X antigen, antibodies to X antigen, and antibodies to the viral polymerase during hepatitis B virus infection.

The characteristics of hepatitis B virus (HBV) X antigen (HBxAg) and antibodies against the X antigen (anti-HBx) and the viral polymerase (anti-pol) were determined in 85 HBV-infected patients. HBxAg was detected in sera positive for HBV e antigen (HBeAg) and HBV DNA in patients with acute and chronic hepatitis, while anti-HBx appeared when markers of viral replication became undetectable. HBxAg was common in the liver among patients with chronic hepatitis independent of HBV replication markers but was closely correlated with elevated alanine aminotransferase, implying that HBxAg in liver may be important in the pathogenesis of chronic infection.

Uses and bioassays in Phyllanthus (Euphorbiaceae): a compilation. II. The subgenus Phyllanthus.

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published in four parts, including (Part IV) analysis, discussion and conclusions concerning apparent clustering of some uses or effects within taxa. This paper (Part II) covers the subgenus Phyllanthus.

Women's perceptions of early detection in breast cancer: how are we doing?

Breast cancer is a significant risk to many women in the United States. It is also a major cause of death among American women. The National Cancer Institute's Year 2000 breast screening goal is to increase the percentage of women aged 50 to 70 years who have physical examination and mammography to 80%.

Characterization of a COL1A1 splicing defect in a case of Ehlers-Danlos syndrome type VII: further evidence of molecular homogeneity.

A child affected by the type VII form of Ehlers-Danlos syndrome (EDS VII) was shown to have a heterozygous structural defect in the amino-terminus of pro-alpha 1(I) collagen. As a result, type I procollagen trimers containing defective subunits are not converted to mature collagen molecules. To identify the cause of the protein abnormality, specifically primed cDNAs and genomic DNA were PCR amplified and sequenced.

Organizer-specific homeobox genes in Xenopus laevis embryos.

The dorsal blastopore lip of the early Xenopus laevis gastrula can organize a complete secondary body axis when transplanted to another embryo. A search for potential gene regulatory components specifically expressed in the organizer was undertaken that resulted in the identification of four types of complementary DNAs from homeobox-containing genes that fulfill this criterion. The most abundant of these encodes a DNA-binding specificity similar to that of the Drosophila melanogaster anterior morphogen bicoid.

Selecting a systematic approach for educating hospitalized cancer patients.

Establishing cancer patient education programs for hospitalized cancer patients may follow a six-stage process that includes planning and strategy selection, selecting channels and materials, developing materials and pretesting, implementation, assessing effectiveness, and obtaining feedback to refine the program. The extent to which each of the stages is followed depends upon which stages are appropriate for the program and the consensus of hospital management.

HIV-1 V3 domain variation in brain and spleen of children with AIDS: tissue-specific evolution within host-determined quasispecies.

DNA coding for the principal neutralization epitope of HIV-1 (the V3 domain of the envelope glycoprotein gp120) was amplified by polymerase chain reaction from postmortem brain and spleen tissue of three perinatally infected children who died of AIDS with progressive encephalopathy. Sequences obtained directly (without cloning) from this DNA were compared with sequences of 52 molecular clones made from this DNA. Cluster analysis showed that V3 domain sequences from two of the three children were similar to sequences from the American MN/SC isolates, while those from one child were more closely similar to the Caribbean RF isolate.

S phase index and ploidy prognostic markers in node negative breast cancer: information for nurses.

The National Cancer Institute (NCI) issued a Clinical Alert on node negative breast cancer in May 1988. Based on findings of clinical studies, the Alert advised that adjuvant hormonal or cytotoxic chemotherapy could have a meaningful impact on the natural history of patients with node negative breast cancer. Prior to the Alert, the majority of women diagnosed with node negative breast cancer did not receive adjuvant treatment.

Monozygotic twins discordant for the Russell-Silver syndrome.

Russell-Silver syndrome is a disorder of unknown cause. A number of familial cases have suggested autosomal dominant inheritance. We report on monozygotic twins discordant for the Russell-Silver syndrome.

Records of usage or assays in Phyllanthus (Euphorbiaceae). I. Subgenera Isocladus, Kirganelia, Cicca and Emblica.

References to either indigenous uses or the results of controlled assays are numerous for species of Phyllanthus (Euphorbiaceae). These citations have been arranged by subgenus, section, subsection and species and will be published as three separate papers, followed by a paper discussing the apparent clustering of some uses or effects within taxa. This paper, the first of the series, covers the subgenera Isocladus, Kirganelia, Cicca and Emblica.

Effects of coping style and relaxation on cancer chemotherapy side effects and emotional responses.

This study was designed to determine (a) the relationship of coping style to cancer chemotherapy side effects and (b) whether coping style moderated the impact of a relaxation intervention on anxiety, depression, and nausea associated with chemotherapy. Forty-eight cancer patients were assigned randomly to receive either progressive muscle relaxation training before chemotherapy (experimental group) or standard care (control group). Spearman correlations indicated that a "blunting" or distraction-oriented coping style was associated with less anticipatory anxiety, less depression, and less nausea during and after chemotherapy.

Spinal cord disease in children with HIV-1 infection: a combined molecular biological and neuropathological study.

An autopsy study was performed on spinal cords from 18 children who died with HIV-1 infection, using standard histopathologic techniques as well as in situ hybridization and immunocytochemistry for HIV-1. Of 16 spinal cords examined by histology, nine had inflammatory cell infiltrates and six had multinucleated cells; both types of lesion are associated with the presence of HIV-1 in central nervous system tissue. HIV-1 type lesions were often present in the spinal cord and brain from the same patient.

Sequence comparison of five polymerases (L proteins) of unsegmented negative-strand RNA viruses: theoretical assignment of functional domains.

The large (L) protein subunit of unsegmented negative-strand RNA virus polymerases is thought to be responsible for the majority of enzymic activities involved in viral transcription and replication. In order to gain insight into this multifunctional role we compared the deduced amino acid sequences of five L proteins of rhabdoviruses (vesicular stomatitis virus and rabies virus) or paramyxoviruses (Sendai virus, Newcastle disease virus and measles virus). Statistical analysis showed that they share an atypical amino acid usage, outlining the uniqueness of the negative-strand virus life style.