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Biomedical subjects

M Bergoin

Publications and source records attributed to M Bergoin.

At least 19 recordsLinked to original sources
PubMed2004

Expression strategy of densonucleosis virus from Mythimna loreyi.

The genome of Mythimna loreyi densovirus (MlDNV) was cloned into the pEMBL(19)+ vector. This clone was infectious upon transfection, both in LD cells and larvae. The genome possessed ITRs of 543 nucleotides of which the distal 126 nucleotides could form a hairpin. The nonstructural (NS) and structural (VP) genes were located on the 5'-halves of the complementary strands and their transcripts started 27 nts downstream of the ITRs. These transcripts had an overlap of 57 nucleotides in middle of the genome. The NS cassette consisted of three genes with NS1 and the overlapping NS2 downstream of NS3. The NS3 gene was spliced out from a fraction of the NS transcripts to allow leaky scanning translation of the downstream bicistronic NS1 and NS2 genes. The four VPs were similarly generated by leaky scanning translation of unspliced mRNA. The 5'-untranslated region of the VP transcript was only seven nucleotides long.

Amino Acid Sequence↗
PubMed2001

High amplification of a densovirus-derived vector in larval and adult tissues of Drosophila.

The Lepidopteran densovirus-derived vector, pJlacZDeltaNS3, is a defective virus genome with an insertion of lacZ DNA in the viral structural protein coding sequence, and a deletion of the sequence coding the non-structural polypeptide NS3. pJlacZDeltaNS3 was injected into Drosophila eggs and the maintenance of the viral genome was monitored by expression of beta-galactosidase and by Southern blot hybridizations. Intense beta-galactosidase activity was observed in many somatic tissues of third-instar larvae and adult flies, in more than 60% of the injected animals. DNA analyses showed that staining in adult tissues correlated with the amplification of the vector. Together, these results suggest the occurrence of early events of integration of the vector into the Drosophila host genome.

Animals↗
PubMed2000

Infectious hypodermal and hematopoietic necrosis virus of shrimp is related to mosquito brevidensoviruses.

We purified and sequenced infectious hypodermal and hematopoietic necrosis virus (IHHNV), a small DNA virus of shrimp, from wild Penaeus stylirostris. The virion has a buoyant density of 1.45 as determined by cesium chloride gradient. Analysis of 3873 nucleotides of the viral genome revealed three large open reading frames (ORFs) and parts of the noncoding termini of the viral genome. The left, mid, and right ORFs on the complementary (plus) strand have potential coding capacities of 666 amino acids (aa) (75.77 kDa), 363 aa (42.11 kDa), and 329 aa (37.48 kDa), respectively. The overall genomic organization is similar to that of the mosquito brevidensoviruses. The left ORF most likely encodes the major nonstructural (NS) protein (NS-1) since it contains conserved replication initiator motifs and NTP-binding and helicase domains similar to those in NS-1 from all other parvoviruses. The IHHNV putative NS-1 shares the highest aa sequence homology with the NS-1 of mosquito brevidensoviruses, Aedes densovirus and Aedes albopictus parvovirus. A search for putative splicing sites revealed that the N-terminal region of NS-1 is very likely located in a small ORF upstream of the left ORF. The right ORF is presumed to encode structural polypeptides (VPs), as in other parvoviruses. Two putative promoters, located upstream of the left and right ORFs, are presumed to regulate expression of NS and VP genes, respectively. Thus, IHHNV is closely related to densoviruses of the genus Brevidensovirus in the family Parvoviridae, and we therefore propose to rename this virus Penaeus stylirostris densovirus (PstDNV).

Amino Acid Sequence↗
PubMed2000

A new densovirus isolated from the mosquito Culex pipiens (Diptera: culicidae).

We have isolated from a laboratory strain of Culex pipiens in which abnormal larval mortality occurred a small icosahedral nonenveloped DNA virus sharing the main biological and biophysical properties of densoviruses (DNVs). Unlike DNVs isolated previously from Aedes species, i.e. the AaeDNV and the AalDNV (Afanasiev, B.N., Galyov, E. E., Buchatsky, L.P., Kozlov, Y.V., 1991. Nucleotide sequence and genomic organization of Aedes densonucleosis virus. Virology 185, 323-336; Boublik, Y., Jousset, F.-X., Bergoin, M., 1994. Complete nucleotide sequence and genomic organization of the Aedes albopictus Parvovirus (AaPV) pathogenic for Aedes aegypti larvae. Virology 200, 752-763), this mosquito DNV named CpDNV possesses a genome of 6 kb separately encapsidated in stoichiometric proportion as 'plus' and 'minus' strands. The lack of sequence homology between the CpDNV and the AalDNV genome and of antigenic cross-reactivity between their capsid polypeptides indicates that these two mosquito DNVs are phylogenetically distant. In contrast, the CpDNV appears to be related to the Junonia coenia densovirus (JcDNV) at both serological and genomic levels.

Animals↗
PubMed2000

The spheroidin of an entomopoxvirus isolated from the grasshopper Anacridium aegyptium (AaEPV) shares low homology with spheroidins from lepidopteran or coleopteran EPVs.

Based on virion morphology, the current virus taxonomy groups entomopoxviruses (EPVs) (Poxvirus: Entomopoxvirinae) from coleopteran and dipteran hosts in separated genera, wilts it keeps viruses infecting either lepidopteran or orthopteran hosts in the same genus. In contrast to the morphological criteria, the few data available from recent studies at the genetic level have suggested that EPVs infecting different insect orders are phylogenetically distant. In order to elucidate EPVs phylogeny we have cloned and sequence the highly conserved/highly expressed spheroidin gene of Anacridium aegyptium entomopoxvirus (AaEPV). This gene and its promoter is of interest for the development of genetic engineering on EPVs. The spheroidin gene was located in the AaEPV genome by Southern blot and hybridisation with specific degenerated oligonucleotides probes synthesised after partial sequencing of the purified spheroidin protein. A total of 3489 bp were sequenced. This sequence included the coding and promoter region of 969 residues 108. 8 kDa protein identified as spheroidin. AaEPV spheroidin contains 21 cysteine residues (2.2%) and 14 N-glycosylation putative sites distributed along the sequence. The cysteine residues are particularly abundant at the C-terminal end of the protein, with 11 residues in the last 118 aa. Our results confirm that the spheroidin is highly conserved only between EPVs isolated from the same insect order. Polyclonal antibodies raised against AaEPV spherules specifically revealed spheroidin in Western Blots failing to cross-react with MmEPV or AmEPV spheroidins or MmEPV fusolin. Comparison of spheroidins at the aa level demonstrate that AaEPV spheroidin shares only 22.2 and 21.9% identity with the lepidopteran AmEPV and the coleopteran MmEPV spheroidins, respectively, but 82.8% identity with the orthopteran MsEPV spheroidin. Only two highly conserved domains containing the sequence (V/Y)NADTG(C/L) and LFAR(I/A) have been identified in all known spheroidins. The phylogenetic tree constructed according to the CLUSTALX analysis program revealed that EPVs are clearly separated in three groups - lepidopteran, coleopteran and orthopteran - according to the insect order of the virus hosts. In base to our results, the split of the genus Entomopoxvirus B dissociating lepidopteran and orthopteran EPVs into two different genera is suggested.

Amino Acid Sequence↗
PubMed2000

Treatment of a case of congenital pseudarthrosis of the tibia-fibular osteosynthesis.

We report the results of a case of congenital pseudarthrosis of the tibia treated by tibiofibular synthesis. A 1-year old girl was first treated by intramedullary fixation followed by an intertibiofibular bone graft. This method failed. She then underwent a new operation that was associated two simultaneous approaches, correction of the axis, tibiofibular synthesis and a new intertibiofibular bone graft. Union was achieved four months later. The child has now been followed up for 20 years. During this time, she has led a normal life as we have observed a "tibialisation" of the fibula. Intramedullary fixation has a success rate of 75% but requires repetitive insertion of intramedullary or telescopic rods. Transplantar intramedullary rods are responsible for significant ankle stiffness. Tibiofibular synthesis associated with an intertibiofibular bone graft after correction of the axis is the equivalent of vascularised graft of the fibula but with neither the difficulties of microsurgery nor valgus deformities of the ankle.

Bone Nails↗
PubMed2000

Protein requirements for assembly of virus-like particles of Junonia coenia densovirus in insect cells.

The coding sequences of four overlapping polypeptides starting at four different in-frame AUG codons and co-terminating at the stop codon of the cap gene of Junonia coenia densovirus (JcDNV) were inserted under the control of the p10 promoter of Autographa californica nucleopolyhedrovirus (AcMNPV) to generate AcMNPV-VP1 (four polypeptides), AcMNPV-VP2 (three polypeptides), AcMNPV-VP3 (two polypeptides), and AcMNPV-VP4 (one polypeptide) recombinant viruses. In all cases, infection of Spodoptera frugiperda cells (Sf9) by each of the four recombinant viruses resulted in the production of virus-like particles (VLPs) 22-25 nm in diameter. The VLPs produced by the three recombinants AcMNPV-VP2, AcMNPV-VP3 and AcMNPV-VP4 were abundant and contained three, two and one polypeptides, respectively. VP4, the shortest polypeptide, thus appears to be sufficient for assembly of VLPs morphologically similar to those formed with two to four polypeptides. The ratio of VPs did not appear to be critical for assembly of the particles. The polypeptide starting at the first AUG immediately downstream from the p10 promoter was always the most abundantly expressed in infected cells, regardless of the construct. In contrast, plaque-purified AcMNPV-VP1 recombinants were unstable and produced less than one-twentieth of the VLPs produced by the others. All VP transcripts started at the TAAG late motif of the p10 promoter and had a poly(A) tail 14 nt downstream of a poly(A) addition signal located 98 nucleotides downstream of the common stop codon. No significant transcription initiation inside the cap sequence of AcMNPV-VP2, AcMNPV-VP3 and AcMNPV-PV4 was observed.

3' Untranslated Regions↗
PubMed2000

Expression of heterologous promoters in Lutzomyia longipalpis and Phlebotomus papatasi (Diptera: Psychodidae) cell lines.

To establish a transient expression system for genes introduced into sand fly cell lines, we tested the expression of the luciferase reporter gene under control of different promoters. Towards this end, we lipofected cell lines obtained from New and Old World sand flies, LL-5 from Lutzomyia longipalpis Lutz & Neiva and PP-9 from Phlebotomus papatasi Scopoli, respectively. The relative levels of luciferase expression were studied under control of Drosophila melanogaster Meigen heat shock protein 70 (hsp70), human cytomegalovirus, simian virus 40 or Junonia coenia (Hübner) densovirus (P9) promoters. The Drosophila heat shock protein 70 promoter, originating from insect genes, functioned as a strong promoter in both cell lines. Promoters from the different virus genes also were capable of driving transgene expression in both cell lines.

Animals↗
PubMed1998

Anterior approach versus posterior approach to surgical treatment of children's supracondylar fractures: comparative study of thirty cases in each series.

The purpose of this study was to consider the surgical treatment of severe supracondylar fractures of the elbow in children, and to compare the anterior approach with the posterior approach used in two homogeneous groups of 30 cases each by two experienced surgeons. Control procedures were maintained with the children of both groups when the plaster was removed, during the fourth month after surgery, and throughout the follow-up that continued for more than 1 year. A posterior approach to surgery is simpler than an anterior approach, but it creates supplementary anatomic damage that can cause circulatory disorders in the external condyle and a higher percentage of limitation in articulation mobility. Thus, although the anterior approach is more technically demanding, it gives better functional results. Because this approach concerns a zone already damaged by the trauma, it eliminates hematoma in the anterior brachial muscle and again places the fragments in the untouched shell of the periosteum.

Adolescent↗
PubMed1997

Indications for surgery in so-called "regular" thoracic and thoracolumbar kyphosis.

Idiopathic thoracic, thoracolumbar, and Scheuermann's kyphosis do not figure in the same global entity. We propose a classification for so-called "regular" kyphosis. This classification is based on the location of the most rigid curvature segment. Segmental kyphosis may be short, in which case we can distinguish between four types: high kyphosis (type I), middle kyphosis (type II), low or thoracolumbar kyphosis (type III), and segmental kyphosis, which can extend along the entire thoracic spine (type IV). The symptomatology and therapeutic indications are different for each type. We report a series of 15 patients (6 female, 9 male), aged between 18 and 33 years (average age 24 years). The mean kyphosis angle (Cobb angle) in type I patients (n = 3) was 75 degrees in type II patients (n = 3) it was 82 degrees, and in type III patients (n = 9) it was 78 degrees. The pain was greater in type III patients. All patients were operated on using a double approach. As the first step, we performed an anterior approach, disc excision, and bone graft. Ten days later, a posterior approach with CD instrumentation was carried out on ten levels. The mean follow-up is 4 years (range 9 months in 7 years). We noticed no neurological complications and one case of late sepsis. Mean angular loss of correction was 6 degrees. The correction obtained depended on the type of kyphosis. We obtained a mean postoperative Cobb angle of 63 degrees in type I curves, 55 degrees in type II, and 45 degrees in type III. The new classification allows a better understanding of regular kyphosis and helps to define clinical and therapeutic approaches. An analysis of the resulting surgical correction can also be made by comparing homogeneous groups of patients.

Adolescent↗
PubMed1997

The treatment of idiopathic scoliosis in adolescents: rotation or in situ bending?

Rotation alone is not fully efficient in order to correct all types of scoliotic curvatures. We report a series of 30 cases instrumented with the EUROS spine system and analyse reductions obtained with in situ rotation or bending alone or with combined maneuvres. The average age of surgery is 17 years for this series composed of 24 female and 6 male patients. The average follow-up is 2.3 years. The curve patterns are displayed with 6 major thoracic, 5 genuine double major, 4 double major thoracic predominant, 6 double major lumbar predominant and 9 double thoracic curves. Combination of both reduction techniques is advisable and is to be made according to the type of curvature and its reducibility in situ bending is made easier with this system without lockers and by reduced diameter of the rod.

Adolescent↗
PubMed1997

Reassessment of the taxonomic position of Rickettsiella grylli.

We determined the 16S rRNA gene sequence of Rickettsiella grylli, an intracellular parasite of Gryllus bimaculatus and related species of crickets. Phylogenetic inferences made from alignment of this sequence with the sequences of other bacteria demonstrated that R. grylli is most closely related to Coxiella burnetii and Legionella species in the gamma subclass of the phylum Proteobacteria. R. grylli was previously thought to be related to members of the order Rickettsiales, but the representatives of this order have been shown to be members of the alpha 1 subclass of the Proteobacteria. Our results indicate that R. grylli should be removed from the order Rickettsiales.

Animals↗
PubMed1997

A nonoccluded reovirus of the olive fly, Dacus oleae.

We have isolated paraspherical viral particles, 60 nm in diameter, from adults of the olive fly (Dacus oleae) collected in Greece. The virus actively replicated in midgut epithelial cells and in advanced infections virions accumulated in microvilli. They were released in the gut lumen and were very abundant in fly faeces. The virions exhibited the salient features of reoviruses, with an external shell and an internal core with a tubular subunit protruding at each vertex of the icosahedron. The viral genome consisted of ten segments of double-stranded RNA totalling 23.4 kbp. Based on its overall properties, this virus can be considered as a nonoccluded insect reovirus.

Animals↗
PubMed1997

Venereal and vertical transmission of the Aedes albopictus parvovirus in Aedes aegypti mosquitoes.

Following per oral infection of Aedes aegypti larvae with Aedes albopictus parvovirus (AaPV), infected males and females adults were tested for their ability to transmit the virus venereally and vertically, respectively. Both types of transmission were observed. A low percentage (2.2%) of AaPV-free females were found contaminated by the virus after mating with AaPV-infected males. Although no significant difference was observed in the fecundity of orally infected and virus-free females, 17.1% of infected ones died before egg laying, whereas no mortality occurred during the same period in virus-free females. There was a clear relationship between the virus titer in the orally infected females and both mortality and infection in their offspring. The virus titer averaged 10(6.2) 50% tissue culture infective doses (TCID50s) in F1 females and 10(3.3) TCID50 in F1 females. Nevertheless, AaPV did not persist in an experimentally infected population of mosquitoes beyond the second generation.

Aedes↗