GOAnno: GO annotation based on multiple alignment

GOAnno is a web tool that automatically annotates proteins according to the Gene Ontology (GO) using evolutionary information available in hierarchized multiple alignments. GO terms present in the aligned functional subfamily can be cross-validated and propagated to obtain highly reliable predicted GO annotation based on the GOAnno algorithm.

AVAILABILITY

The web tool and a reduced version for local installation are freely available at http://igbmc.u-strasbg.fr/GOAnno/GOAnno.html

SUPPLEMENTARY INFORMATION

The website supplies a detailed explanation and illustration of the algorithm at http://igbmc.u-strasbg.fr/GOAnno/GOAnnoHelp.html.

Unexpected pulmonary uptake of adenovirus vectors in animals with chronic liver disease

When adenovirus vectors are injected intravenously, most of the virions are quickly taken up by the reticuloendothelial system, primarily by the liver macrophages known as Kupffer cells. However, little is known about the behavior of adenovirus vectors when there is pre-existing liver disease. To study this, we examined the biodistribution of intravenously injected vector in a rat model of cirrhosis induced by bile duct ligation. Using quantitative PCR and fluorescently tagged adenovirus vectors, we observed a significant reduction in vector uptake by the cirrhotic liver and increased accumulation in the lungs. Immunocytochemistry and electron microscopy demonstrated that this was due to changes in the reticuloendothelial system, with the vector being taken up by large numbers of pulmonary intravascular macrophages in the lungs of cirrhotic rats. Interestingly, expression of vector-encoded luciferase was significantly reduced in the livers of cirrhotic rats, but was not increased in the lungs. These data demonstrate that the biodistribution of adenovirus vectors in rats is altered by cirrhosis, which suggests the possibility that these vectors might behave unexpectedly in patients with pre-existing liver conditions, particularly since pulmonary reticuloendothelial changes are known to occur in human disease.

The N- and C-terminal regions of rotavirus NSP5 are the critical determinants for the formation of viroplasm-like structures independent of NSP2

Molecular events and the interdependence of the two rotavirus nonstructural proteins, NSP5 and NSP2, in producing viroplasm-like structures (VLS) were previously evaluated by using transient cellular coexpression of the genes for the two proteins, and VLS domains as well as the NSP2-binding region of NSP5 were mapped in the context of NSP2. Review of the previous studies led us to postulate that NSP2 binding of NSP5 may block the N terminus of NSP5 or render it inaccessible and that any similar N-terminal blockage may render NSP5 alone capable of producing VLS independent of NSP2. This possibility was addressed in this report by using two forms of NSP5-green fluorescent protein (GFP) chimeras wherein GFP is fused at either the N or the C terminus of NSP5 (GFP-NSP5 and NSP5-GFP) and evaluating their VLS-forming capability (by light and electron microscopy) and phosphorylation and multimerization potential independent of NSP2. Our results demonstrate that NSP5 alone can form VLS when the N terminus is blocked by fusion with a nonrotavirus protein (GFP-NSP5) but the C terminus is unmodified. Only GFP-NSP5 was able to undergo hyperphosphorylation and multimerization with the native form of NSP5, emphasizing the importance of an unmodified C terminus for these events. Deletion analysis of NSP5 mapped the essential signals for VLS formation to the C terminus and clearly suggested that hyperphosphorylation of NSP5 is not required for VLS formation. The present study emphasizes in general that when fusion proteins are used for functional studies, constructs that represent fusions at both the N and the C termini of the protein should be evaluated.

[EVE, a regional campaign for the screening of cervical cancer. Organization, 7-years results and perspectives]

OBJECTIVE

Based on the 7-years results, assess the interest of organised cervical cancer screening on regional level (the EVE campaign). ORGANISATION AND METHOD: The screening relied on existing medical structures. The centralised data collection, with data from the cyto-pathology laboratories assessed the quality of screening and the participation of the women to the follow-up of abnormal smears. The campaign run by a local women's rights association and sponsored by National educational and health information funds (FNPEIS) and the local councils.

RESULTS

To date, 814 649 smears in the Bas-Rhin and 62 227 in the Haut-Rhin have been collected. After 3 years, 72% of women aged 25 to 64 in the year 1997, in the Bas-Rhin, had had at least one smear, and 82% after 5 years. Inadequate smears represented less than 1% of all smears of the region. Pathological smears represented around 4% of the total and benefited from strict monitoring which could be improved. However this could be improved on since only 75% of women in whom a low-grade lesion was suspected underwent a second examination within the year that followed. The rate was on 80% for those with suspected high-grade lesions. Reminders made by the EVE association, in agreement with practitioners, permitted postponed follow-up and improved screening coverage.

CONCLUSION

The EVE programme clearly shows that organized screening is feasible in France because the results obtained are satisfactory in terms of screening coverage and quality of smears. Centralised data collection permits detection of possible weak points and contributes to the improvement in efficacy.

[Rapid induction of withdrawal with opiate antagonists under anesthesia: an alternative to treatment of opiate dependence?]

Rapid induction of withdrawal by opiate antagonists under anesthesia is an opiate detoxification technique. This technique is useful to reduce intensity and duration of withdrawal. Therefore, this technique represents an alternative strategy in the treatment of opiate addicted patients. This paper attempts to present a brief history of this technique, and a critical review of related issues.

[Sonographic imaging of lymphatic vessels compared to other methods]

This paper reviews for the first time the normal and abnormal appearances of lymphatic channels of the skin using ultrasound. After a review of anatomy and histology, the authors present the current imaging modalities available for lymph vessel imaging. The ultrasound examination is presented with a description of the author's technique as well as the technical requirements of the ultrasound unit (12 MHz linear probe with a resolution of 400 microns). They present the ultrasound appearance of normal lymphatic channels and their relationships to the dermis, hypodermis and lymph nodes, and at last the ultrasound appearance of abnormal lymphatic pathways

Comparative evolution of muscular dystrophy in diaphragm, gastrocnemius and masseter muscles from old male mdx mice

X chromosome-linked muscular dystrophic mdx mouse lacks the sarcolemmal protein dystrophin and represents a genetic homologue of human Duchenne muscular dystrophy (DMD). The present study analysed some aspects of pathological processes such as fibrosis, frequency of centralized nuclei, presence of degenerative or regenerative fibres, expression of utrophin and associated protein complexes, and myosin heavy chain isoforms in three muscles [diaphragm (DIA), gastrocnemius (GTC) and masseter (MAS)] from old male mdx mice. All parameters investigated comparatively in these pathological muscles provided evidence that the MAS mdx muscle presents a slight deterioration pattern in comparison to that of DIA and GTC muscles. Utrophin and associated proteins are present in many cell clusters with continuous membrane labelling in MAS muscle. Respective proportions of myosin heavy chain isoforms, measured by electrophoresis/densitometry, showed only slight change in GTC muscle, significant evolution in DIA muscle but drastic isoform conversions in MAS muscle. These results highlighted the difference in deterioration susceptibility of various muscles to muscular dystrophy. The reason why this occurs in MAS muscles is still obscure and discussed in terms of the comparative developmental origins of these muscles.

Efficacy of a competitive enzyme-linked immunosorbent assay (cELISA) for estimating prevalence of immunity to rabbit haemorrhagic disease virus (RHDV) in populations of Australian wild rabbits (Oryctolagus cuniculus)

This study examines the efficacy of a cELISA in estimating the prevalence of immunity to rabbit haemorrhagic disease virus (RHDV) in wild rabbits in Australia. Rabbits (n = 343) captured from six locations in Victoria and Queensland were experimentally challenged with a lethal oral dose (1500 50%-lethal doses, LD50) of RHDV. Death or survival to challenge was used to determine the performance characteristics of the test. The diagnostic specificity, sensitivity and accuracy were highly variable between sites, making it difficult to select a representative cut-off value for all sites that achieved a reasonable level of accuracy for the prediction of surviving and non-surviving rabbits. Estimates of prevalence of immunity were biased owing to effects of site of capture (time of capture) and age structure of the population. Using predictive equations, the best estimates of survival were ±10% but these results came from a limited range of sites, all of which had survival in the range 49–70%. The cELISA will determine whether the RHDV is present in rabbit populations but it should be used with caution when estimating the prevalence of immunity to RHDV. The cELISA may thus be limited in its application for examining the epidemiology of RHDV in Australian rabbit populations.

Programmed cell death in the unicellular protozoan parasite Leishmania

In the present study we have demonstrated some features characterizing programmed cell death (PCD) in the unicellular protozoan parasite Leishmania donovani, the causative agent of visceral Leishmaniasis. We report that PCD is initiated in stationary phase cultures of promastigotes and both in actively growing cultures of axenic amastigotes and promastigotes upon treatment with anti Leishmanial drugs (Pentostam and amphotericin B). However, the two cell types respond to antileishmanial drugs differently. The features of PCD in L. donovani promastigotes are nuclear condensation, nicked DNA in the nucleus, DNA ladder formation, increase in plasma membrane permeability, decrease in the mitochondrial membrane potential (DeltaPsi m) and induction of a PhiPhiLux (PPL)-cleavage activity. PCD in both stationary phase culture and upon induction by amphotericin B resulted first in the decrease of mitochondrial membrane potential followed by simultaneous change in plasma membrane permeability and induction of PPL-cleavage activity. Of the total PPL-cleavage activity, several caspase inhibitors inhibited a significant amount (21-34%). Inhibitors of cathepsin or calpain did not inhibit PPL-cleavage activity. Taken together this study demonstrates that the characteristic features of PCD exist in unicellular protozoan Leishmania donovani. The implication of PCD on the Leishmania pathogenesis is discussed.

Giant-cell tumor of bone arising from the falx cerebri. A case report

The histological and ultrastructural features of a giant-cell tumor of bone arising in the falx cerebri of a 27 year-old man are described. The tumor was embedded in the medial aspect of the left frontal lobe and was not attached to any of the bones of the skull. At surgery, the tumor was lightly adherent to the falx and was easily extracted. Histologically, the tumor was composed of mononuclear spindle-shaped and ovoid stromal cells, multinuclear giant cells containing 20-30 nuclei, and foci of osteoid and bone production. Hemorrhagic and cystic areas were also present within the tumor. Ultrastructurally, the spindle-shaped cells resembled fibroblasts and were surrounded by small bundles of collagen fibrils. The ovoid cells contained numerous mitochondria, abundant rough endoplasmic reticulum, vesicles, lysosomes, phagosomes and osseous material in the cytoplasm suggesting their monocyte-macrophage lineage. These cells were closely apposed and displayed evidence of fusion in the form of focal and linear subplasmalemmal densities to form multinucleated giant cells with similar organelles and multiple nuclei. It is suggested that the primary giant cell tumor of the one arose from the metaplastic ossification of the falx. To our knowledge, a giant-cell tumor of bone arising from the falx cerebri has not been previously described.

Programmed cell death in the unicellular protozoan parasite Leishmania

In the present study we have demonstrated some features characterizing programmed cell death (PCD) in the unicellular protozoan parasite Leishmania donovani, the causative agent of visceral Leishmaniasis. We report that PCD is initiated in stationary phase cultures of promastigotes and both in actively growing cultures of axenic amastigotes and promastigotes upon treatment with anti Leishmanial drugs (Pentostam and amphotericin B). However, the two cell types respond to antileishmanial drugs differently. The features of PCD in L. donovani promastigotes are nuclear condensation, nicked DNA in the nucleus, DNA ladder formation, increase in plasma membrane permeability, decrease in the mitochondrial membrane potential (DeltaPsi m) and induction of a PhiPhiLux (PPL)-cleavage activity. PCD in both stationary phase culture and upon induction by amphotericin B resulted first in the decrease of mitochondrial membrane potential followed by simultaneous change in plasma membrane permeability and induction of PPL-cleavage activity. Of the total PPL-cleavage activity, several caspase inhibitors inhibited a significant amount (21-34%). Inhibitors of cathepsin or calpain did not inhibit PPL-cleavage activity. Taken together this study demonstrates that the characteristic features of PCD exist in unicellular protozoan Leishmania donovani. The implication of PCD on the Leishmania pathogenesis is discussed.

Early detection of endogenous retroviruses in chemically induced mouse cells

Endogenous retroviral sequences are present as an integral part of eukaryotic genomes. Although the majority of these sequences are defective, a few can produce infectious virus, either spontaneously upon long-term culture or by treatment with various chemical or other agents. Early, extensive studies of retrovirus induction were done in mouse cells; however, similar studies have not been done using state-of-the-art virus detection assays and with cells of other mammalian species. To investigate induction and detection of occult retroviruses in cells of different species, especially primate cells that are used in production of biologics, we have initially determined the optimum conditions for retrovirus induction in chemically treated K-BALB mouse cells using highly sensitive product-enhanced reverse transcriptase (PERT) assays as well as transmission electron microscopy (TEM). Retrovirus induction was detected at day 1 post-drug treatment under all test conditions but was optimum using 30 microg ml(-1) of 5-iododeoxyuridine (IdU) for 24 h. Additionally, the combination of IdU and 5-azacytidine specifically enhanced activation of type C particles. RT activity was detected by PERT assays in one microliter equivalent of test sample and retroviral particle production was seen by TEM analysis. The induction of infectious murine leukemia retroviruses was confirmed by infectivity assays and correlated with PERT activity. These results indicate that strategies for detection of occult viral agents should include optimization of induction conditions using multiple viral detection assays to evaluate virus activation.

A model for melanosome biogenesis based on the purification and analysis of early melanosomes

Melanosome biogenesis and function were studied after purification of early stage melanosomes and characterization of specific proteins sorted to that organelle. Melanosomes were isolated from highly pigmented human MNT1 melanoma cells after disruption and initial separation by sucrose density gradient centrifugation. Low-density sucrose fractions were found by electron microscopy to be enriched in stage I and stage II melanosomes, and these fractions were further separated and purified by free flow electrophoresis. Tyrosinase and dopachrome tautomerase (DCT) activities were found exclusively in stage II melanosomes, even though DCT (and to some extent tyrosinase) proteins were sorted to stage I melanosomes. Western immunoblotting revealed that these catalytic proteins, as well as TYRP1, MART1, and GP100, were cleaved and inactivated in stage I melanosomes. Proteolytic cleavage was critical for the refolding of GP100 within the melanosomal milieu, and subsequent reorganization of amorphous stage I melanosomes into fibrillar, ovoid, and highly organized stage II melanosomes appears to stabilize the catalytic functions of melanosomal enzymes and allows melanin biosynthesis to begin. These results provide a better understanding of the structural features seen during melanosome biogenesis, and they yield further clues as to the physiological regulation of pigmentation.

Effect of influenza virus matrix protein and viral RNA on ribonucleoprotein formation and nuclear export

The formation of influenza virus ribonucleoprotein (RNP) is a necessary step in viral assembly and maturation in infected cells, but the mechanism remains incompletely understood. Influenza virus proteins such as matrix (M1) and cellular proteins have been implicated in assembly and transport of RNP. To study the assembly of RNP and the translocation of RNP complexes in cells, RNPs were reconstituted from nucleoprotein (NP), M1, and viral RNA (vRNA) synthesized in vitro. The syntheses were accomplished using specific plasmids in a system coupling transcription and translation under the control of the T7 promoter. The density of the resulting RNP complexes was analyzed by glycerol gradient centrifugation and the morphology was examined by transmission electron microscopy. Protomers of NP self-assembled into circular oligomers regardless of the presence of vRNA or M1. However, helical structures similar in conformation and density to RNPs purified directly from influenza virus were formed only when M1 and vRNA were also present. In the absence of vRNA, no helical structures were formed from NP and M1. The plasmids also contained the CMV promoter, which permitted expression of M1, NP, and vRNA in Madin-Darby canine kidney (MDCK). M1 and NP were both present in the cytoplasm of MDCK also expressing vRNA, but NP was retained in the nucleus of cells expressing M1 without vRNA. Our data demonstrate for the first time that vRNA and M1 together promote the self-assembly of influenza virus NP into the quaternary helical structure typical of the viral RNP. The results also indicate that the interaction of NP with vRNA and M1 in a system devoid of other viral proteins can lead to translocation of RNP from nucleus to cytoplasm.