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1.
Encephale ; 42(6): 582-588, 2016 Dec.
Artigo em Francês | MEDLINE | ID: mdl-27644917

RESUMO

Left temporal arachnoid cyst and specific learning disorders associated with pervasive developmental disorders - not otherwise specified (PDD-NOS): contributions of an integrative neuro-psychomotor, neuropsychological, psychopathological and neurosurgical approach about a case report in a child (François). With DSM-IV and DSM-IV-TR, the terminology of pervasive developmental disorders (PDD) covers two main categories of infantile disorders: disorders of "strictly" autistic nature and pervasive developmental disorders - not otherwise specified (PDD-NOS). Under the terminology of multiple complex developmental disorder (MCDD), it is proposed to classify children presenting symptoms approaching the psychotic disharmonies and usually diagnosed as PDD-NOS. Such a category of developmental disorders is now included without nosographic distinction in the autistic spectrum in the Diagnostic and Statistical Manual of mental disorders (DSM-V). CASE REPORT: We are reporting a case report of a 6-year-old boy which shows a PDD-NoS/MCDD complex symptomatology type. This child presents multiple disorders: minor neurological signs (soft signs), neuro-psychomotor disorders, developmental coordination disorder (DCD), communication, thought, and regulation of emotions disorders, attention deficit disorders (ADD); in the presence of a high verbal intellectual potential, which makes it difficult to establish a clear diagnosis. A cerebral magnetic resonance imaging (MRI) was carried out due to the presence of minor neurological signs (soft signs) and of neurodevelopmental multiple disorders. The MRI revealed a voluminous arachnoid temporo-polar left cyst with a marked mass effect on the left temporal lobe. DISCUSSION: A neurosurgical intervention allowed to observe the gradual disappearance of the specific symptomatology (in particular soft signs, neuro-psychomotor functions and autistic symptoms) secondary to the interference of the cyst's pressure with intracranial areas involving neurological and psychopathological abnormalities, underlying at the same time the reversibility of the disorders after decompression as demonstrated in some studies. There are always, with a quantitative and qualitative decrease, an emotional dysregulation, a DCD, an ADD as well as impairments in the executive functions. CONCLUSION: This clinical case underlines the necessity of an evaluation in a transdisciplinary way and to follow the developmental evolution of the child in order to focus adapted therapeutics. Furthermore, with neurodevelopmental disorders not specified, it is important to examine the presence of soft signs with standardized neuro-psychomotor assessment, and then, to propose an MRI investigation. To our knowledge, this is the first report in the literature with a school age child of an unusual association between a temporal arachnoid cyst associated with PDD-NOS/MCDD.


Assuntos
Cistos Aracnóideos/terapia , Transtornos Globais do Desenvolvimento Infantil/terapia , Procedimentos Neurocirúrgicos/métodos , Transtorno de Aprendizagem Específico/terapia , Lobo Temporal/cirurgia , Cistos Aracnóideos/psicologia , Cistos Aracnóideos/cirurgia , Transtorno do Deficit de Atenção com Hiperatividade/etiologia , Transtorno Autístico/etiologia , Transtorno Autístico/terapia , Criança , Transtornos Globais do Desenvolvimento Infantil/psicologia , Transtornos Globais do Desenvolvimento Infantil/cirurgia , Terapia Combinada , Humanos , Imageamento por Ressonância Magnética , Masculino , Transtornos das Habilidades Motoras/etiologia , Escalas de Graduação Psiquiátrica , Transtornos Psicomotores/etiologia , Transtornos Psicomotores/terapia , Transtorno de Aprendizagem Específico/psicologia , Transtorno de Aprendizagem Específico/cirurgia , Resultado do Tratamento
2.
Encephale ; 38(4): 318-28, 2012 Sep.
Artigo em Francês | MEDLINE | ID: mdl-22980473

RESUMO

BACKGROUND: Specific language impairment (SLI) is a primary developmental disorder in which language is significantly more impaired than other developmental domains. Abnormal electroencephalographic recordings without clinical seizures are often observed. The aim of this retrospective study was to characterize the frequency of these abnormalities, to describe them and to analyze their association with anamnestic, clinical, paraclinical and evolution characteristics. METHODS: The cases of 35 children with a diagnosis of SLI, who also underwent electroencephalography and MRI, were systematically reviewed retrospectively. RESULTS: In this population, aged between 4 and 7 years, 49% (n=17) of patients exhibited a specific expressive language disorder and 51% (n=18) a specific receptive disorder. Forty-nine percent of the children featured abnormal electroencephalography results. Abnormalities were essentially localized on the left side of the brain and in two specific regions: the temporo-occipital (60%) and the frontorolandic (30%) regions. The groups with and without abnormalities were compared statistically with each other in terms of clinical, paraclinical and evolution characteristics. Evolution data were available for 24 patients through a telephone interview and for nine patients through a new complete language evaluation. The comparison of the two groups showed significant differences in terms of severity of the phonological disorder, a higher number of delayed acquisition of walking and cleanliness and a higher range of non specific psychomotor difficulties. DISCUSSION: A large proportion of children suffering from SLI present abnormal electroencephalography recordings with no clinical seizures. This rate is much higher than in the general population and the abnormalities are essentially localized on the left side of the brain in regions known for their specific role in language development. These abnormalities are more frequent in children with a severe phonological disorder, suggesting that they may share common pathophysiological features with SLI. CONCLUSION: The presence of EEG abnormalities in a large group of patients suffering from SLI associated with minor neurological abnormalities suggests a possible theoretical neurodevelopmental model. Minor neurodevelopmental abnormalities, genetically transmitted or acquired during the pre- or perinatal period, may create vulnerability towards SLI. This vulnerability, in conjunction with environmental influences such as family environment, linguistic stimuli, exposure to multiple languages, or transitory hearing loss, might take the form of SLI. This hypothesis underlines the importance of prevention and early detection of SLI when identifying vulnerable subjects. Monitoring the family early through parental guidance and early school support would facilitate the acquisition of language.


Assuntos
Dano Encefálico Crônico/diagnóstico , Dano Encefálico Crônico/fisiopatologia , Córtex Cerebral/fisiopatologia , Eletroencefalografia , Transtornos do Desenvolvimento da Linguagem/diagnóstico , Transtornos do Desenvolvimento da Linguagem/fisiopatologia , Mapeamento Encefálico , Criança , Pré-Escolar , Comportamento Cooperativo , Dominância Cerebral/fisiologia , Potenciais Evocados/fisiologia , Feminino , Lobo Frontal/fisiopatologia , Humanos , Comunicação Interdisciplinar , Testes de Linguagem , Imageamento por Ressonância Magnética , Masculino , Lobo Occipital/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Lobo Temporal/fisiopatologia
3.
Science ; 179(4080): 1323-4, 1973 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-17835938

RESUMO

Natural populations of Sulfolobus, a new genus of bacteria occurring in sulfur-rich, acid hot springs and soils, were found to oxidize large amounts of sulfur to sulfuric acid at temperatures up to 85 degrees C. These bacteria are important high-temperature geochemical agents in solfatara soils.

5.
J Mol Biol ; 240(2): 127-37, 1994 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-8027997

RESUMO

The crystal structure of Fab17-IA, an antigen-binding fragment from a murine immunoglobulin that neutralizes human rhinovirus 14 (HRV14), has been solved to 2.7 A resolution. Fab17-IA crystallized into three different space groups depending upon the method used to purify the intact antibody. The structure was determined by use of molecular and isomorphous replacement methods. The current model has a crystallographic R-factor of approximately 19% for 10,192 independent reflections between 8 and 2.7 A. Correlation coefficient calculations showed that the Fab17-IA structure can be fit into the Fab17-IA/HRV14 image reconstruction density to within 5 A positional accuracy and to within a few degrees of rotation. The resulting interface of the docked antibody was examined and showed extensive charge and shape complementarity with the virus surface that was supported by site-directed mutagenesis experiments. The success of this approach validates the utility of combining X-ray crystallography with cryo-electron microscopy of complex macromolecular assemblies.


Assuntos
Anticorpos Antivirais/química , Complexo Antígeno-Anticorpo/química , Fragmentos Fab das Imunoglobulinas/química , Rhinovirus/química , Sequência de Aminoácidos , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Complexo Antígeno-Anticorpo/imunologia , Complexo Antígeno-Anticorpo/ultraestrutura , Sequência de Bases , Criopreservação , Cristalografia por Raios X , Humanos , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/ultraestrutura , Microscopia Eletrônica , Modelos Moleculares , Dados de Sequência Molecular , Testes de Neutralização , Conformação Proteica , Rhinovirus/imunologia , Rhinovirus/ultraestrutura , Homologia de Sequência de Aminoácidos , Relação Estrutura-Atividade
6.
J Med Genet ; 41(1): 6-10, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14729817

RESUMO

BACKGROUND: Patients with hereditary haemochromatosis (HH) are usually homozygous for the C282Y mutation in the HFE gene. They have variable expression of iron overload and present with a variety of complications, including liver disease, diabetes, arthropathy, fatigue, and cardiomyopathy. The mitochondrial 16189 variant is associated with diabetes, dilated cardiomyopathy, and low body fat at birth, and might contribute to genetic predisposition in further multifactorial disorders. The objective of this study was to determine the frequency of the 16189 variant in a range of patients with haemochromatosis, who had mutations in the HFE gene. METHODS: Blood DNA was analysed for the presence of the 16189 variant in British, French, and Australian C282Y homozygotes and controls, with known iron status, and in birth cohorts. RESULTS: The frequency of the mitochondrial 16189 variant was found to be elevated in individuals with haemochromatosis who were homozygous for the C282Y allele, compared with population controls and with C282Y homozygotes who were asymptomatic (42/292 (14.4%); 102/1186 (8.6%) (p = 0.003); and 2/64 (3.1%) (p = 0.023), respectively). CONCLUSIONS: Iron loading in C282Y homozygotes with HH was exacerbated by the presence of the mitochondrial 16189 variant.


Assuntos
Substituição de Aminoácidos/genética , DNA Mitocondrial/genética , Hemocromatose/genética , Homozigoto , Mutação/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Cisteína/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Frequência do Gene/genética , Genótipo , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Sobrecarga de Ferro/genética , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Fenótipo , Tirosina/genética
7.
Biomaterials ; 11: 57-62, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2168765

RESUMO

After a brief review of the main characteristics of some spectroscopic and microscopic methods for surface and interface analysis, preliminary and prospective studies of biocompatible materials (hydroxyapatite, alumina) for implant coating purposes are presented. The results show that the use of complementary techniques allows information on the physical and chemical properties of the coatings both on a microscopic and on an atomic scale to be obtained.


Assuntos
Materiais Biocompatíveis , Teste de Materiais , Próteses e Implantes , Aço Inoxidável , Óxido de Alumínio , Pinos Ortopédicos , Durapatita , Hidroxiapatitas , Microscopia Eletrônica de Varredura , Estudos Prospectivos , Propriedades de Superfície
8.
Arch Virol Suppl ; 9: 111-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8032243

RESUMO

The WIN drugs and similar hydrophobic compounds that insert into the capsid of picornaviruses have been shown to block viral uncoating. In some of the human rhinoviruses they also block attachment of virus to cells. Spontaneously occurring drug-resistant mutants of human rhinovirus 14 and poliovirus type 3 were selected for their ability to make plaques in the presence of the selecting drug. The HRV-14 mutants either prevented drug binding or allowed the virus to attach to cells in the presence of drug. About two thirds of the poliovirus mutants were dependent on the presence of drug for plaque formation. In single cycle growth curves, drug was not required for the formation of drug-dependent progeny virus. However, progeny virus grown without drug never accumulated outside of cells, thus making the formation of plaques impossible. This behavior was apparently caused by the extreme thermolability of these mutants. In the absence of drug, heating to 37 degrees C rapidly converted them to non-infectious particles with a sedimentation coefficient of 135S.


Assuntos
Antivirais/farmacologia , Capsídeo/genética , Mutação , Poliovirus/genética , Rhinovirus/genética , Resistência Microbiana a Medicamentos/genética , Temperatura Alta/efeitos adversos , Poliovirus/efeitos dos fármacos , Poliovirus/crescimento & desenvolvimento , Rhinovirus/efeitos dos fármacos , Rhinovirus/crescimento & desenvolvimento , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
9.
Presse Med ; 15(41): 2051-5, 1986 Nov 22.
Artigo em Francês | MEDLINE | ID: mdl-2949227

RESUMO

An epidemiological and clinical survey of rheumatic fever was carried out in Martinique. The clinical manifestations, portal of entry and socio-economic facilitating factors appeared to be the same as those observed in metropolitan France when the disease occurred with a similar frequency. The prevalence and severity of rheumatic fever in Martinique are still high (in 1982, 49 new cases in a population of 300,000, including 12 with severe carditis), but they tend to diminish as the eradication campaign goes on. The reasons for the persistence of the disease and the problems encountered in the eradication campaign are discussed in the light of epidemiological data collected during the last 3 years.


Assuntos
Febre Reumática/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Martinica , Febre Reumática/diagnóstico , Febre Reumática/microbiologia , Estações do Ano , Fatores Socioeconômicos , Infecções Estreptocócicas/diagnóstico , Fatores de Tempo
11.
Arch Virol ; 151(10): 1933-46, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16732496

RESUMO

Interferons induced by viral infections can have powerful immuno- modulatory effects, and several epidemiologic studies have found an association between certain viral infections and reduced prevalence of allergy. We hypothesized that allergenic proteins could be synthesized by a replicating virus, and this construct could be useful as an immunomodulator. To test this hypothesis, we cloned an allergenic protein (ovomucoid [OVM]) into a murine picornavirus (Mengo virus) vector. This plasmid has a multicloning site surrounded by auto-catalytic sequences so that a foreign protein will be cleaved from viral proteins during replication. OVM sequences were cloned in the context of full-length viral genome cDNA, T7 RNA transcripts of this plasmid were transfected into HeLa cells, and recombinant virus plaques appeared on the second passage. Sequence analysis of recombinant viruses derived from individual plaques demonstrated that three viral isolates contained up to 2/3 of the OVM coding sequence, which was retained by the viruses after 5 additional passages in HeLa cells. The experiments verify the stable expression of immunoreactive OVM subunits by replicating viruses. These virus/allergen constructs could provide a tool to evaluate whether intracellular presentation of allergenic proteins in the context of a viral infection could prevent allergic sensitization upon re-challenge.


Assuntos
Alérgenos/biossíntese , Mengovirus/fisiologia , Ovomucina/biossíntese , Vírus Reordenados/fisiologia , Alérgenos/genética , Animais , Infecções por Cardiovirus/virologia , Vetores Genéticos/metabolismo , Vetores Genéticos/fisiologia , Genoma Viral/genética , Células HeLa/metabolismo , Humanos , Mengovirus/genética , Mengovirus/metabolismo , Camundongos , Ovomucina/genética , Ovomucina/imunologia , Plasmídeos/genética , Vírus Reordenados/metabolismo , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Recombinação Genética , Inoculações Seriadas , Especificidade da Espécie , Transfecção , Replicação Viral
12.
Sem Hop ; 60(13): 923-6, 1984 Mar 22.
Artigo em Francês | MEDLINE | ID: mdl-6326275

RESUMO

When the general practitioner is convinced that a somatic symptom covers a psychosomatic problem, he may choose one of two strategies. The first is to minimize it on the grounds of possible subsequent change or to spare a vital compromise (duty of reservation). The second is to ignore the request in order to offer the possibility of implementing his therapeutic conviction. In this strategic choice, the doctor's authority as a "trustee" is pitted, in practice, against the inconsistent and irresolute nature of the request, and the shortcomings of the institution or socioeconomic level. Strangely enough, psychologising information may jeopardize the therapeutic commitment. The higher the cultural level, the greater the deviation, especially in depression. Observations from everyday practice in urban centers exemplify the variety of these approaches.


Assuntos
Transtornos Psicofisiológicos/diagnóstico , Adolescente , Adulto , Criança , Medicina de Família e Comunidade/métodos , Feminino , Humanos , Masculino , Relações Médico-Paciente , Transtornos Psicofisiológicos/psicologia , Transtornos Psicofisiológicos/terapia
13.
J Virol ; 15(5): 1088-95, 1975 May.
Artigo em Inglês | MEDLINE | ID: mdl-1142473

RESUMO

The polypeptide composition of virions of spleen necrosis virus, a reticuloendotheliosis virus, was determined using electrophoresis on sodium dodecyl sulfate-containing, 10 percent polyacrylamide gels. Ten polypeptides were resolved. Four of these were present in minor and somewhat variable amounts. Two proteins, gp71 and gp22, contained D-glucosamine and were located on the outer surface of the lipid envelope, as demonstrated by lactoperoxidase-catalyzed iodination and by bromelain digestion. The results suggest that two of the minor proteins, p36 and p26, were also located on the outer surface, although they lacked D-glucosamine. Treatment of the virus with 0.25 percent Nonidet P-40 and 1 percent dithiothreitol produced a subparticle with a buoyant density of approximately 1.31 g/cm-3. This particle was relatively enriched with polypeptides p77, p62, and p50 and contained small amounts of three other polypeptides.


Assuntos
Doenças Linfáticas/microbiologia , Peptídeos/análise , Proteínas Virais/análise , Viroses/microbiologia , Vírus/metabolismo , Eletroforese em Gel de Poliacrilamida , Vírus/análise , Vírus/enzimologia
14.
J Virol ; 67(3): 1246-54, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8382293

RESUMO

Twenty-two spontaneous mutants of the Sabin strain of poliovirus type 3 were selected for drug resistance by plating on HeLa cell monolayers in the presence of WIN 51711, an uncoating inhibitor. When replated in the presence and absence of drug, two classes of mutants were observed; mutants displayed either a drug-dependent or a non-drug-dependent phenotype, in the proportion 14:8. Non-drug-dependent mutants plaqued with equal efficiency in the presence or absence of drug. By contrast, drug-dependent mutants made no plaques in the absence of drug, except for revertants. In single-step growth curve experiments, however, drug-dependent mutants grew as well in the absence of drug as in its presence. This paradoxical behavior of dependent mutants was traced to extreme thermolability at 37 degrees C (12- to 30-s half-life) in the absence of drug. Thermolability was exhibited only after the virus was released from the cell, implying the presence of a cell-associated protective factor, possibly pocket factor. Thus, in the absence of a thermostabilizing drug, drug-dependent mutants decayed too rapidly after release to permit spread in the plaque assay. The thermodecay product was shown to consist of 135S particles lacking VP4.


Assuntos
Antivirais/farmacologia , Resistência Microbiana a Medicamentos , Isoxazóis/farmacologia , Poliovirus/crescimento & desenvolvimento , Vírion/crescimento & desenvolvimento , Células HeLa , Temperatura Alta , Humanos , Mutagênese , Poliovirus/efeitos dos fármacos , Poliovirus/genética , Vírion/efeitos dos fármacos , Replicação Viral
15.
J Virol ; 67(6): 3126-33, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8388493

RESUMO

Nineteen neutralizing murine monoclonal antibodies against poliovirus type 1, including representatives reacting with each of the antigenic sites on the virion, were tested for their abilities to neutralize the virus either before or after attachment to susceptible cells. All antibodies neutralized unattached virus; six had reasonable titers of postabsorption neutralization (PAN). Experiments with antibodies lacking PAN activity showed that Fc-specific rabbit anti-mouse antibodies could confer PAN activity. PAN was shown to involve the prevention of the cell-mediated conversion of virus to 135S and 80S particles. Evidence that one of the PAN-positive antibodies probably bound bivalently to preabsorbed virions, whereas a PAN-negative antibody bound monovalently, is presented. Two PAN-positive antibodies were added to an excess of virus in suspension, and only one antibody caused the virus to aggregate.


Assuntos
Anticorpos Antivirais , Poliovirus/imunologia , Vírion/imunologia , Anticorpos Monoclonais , Reações Antígeno-Anticorpo , Fragmentos Fc das Imunoglobulinas/imunologia , Cadeias kappa de Imunoglobulina/imunologia , Testes de Neutralização , Poliovirus/crescimento & desenvolvimento , Poliovirus/metabolismo , Vírion/crescimento & desenvolvimento , Vírion/metabolismo , Replicação Viral/imunologia
16.
Acta Crystallogr D Biol Crystallogr ; 51(Pt 4): 490-5, 1995 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-15299835

RESUMO

Capsid-binding drugs that inhibit the first stage of picornaviral uncoating were used to select drug-resistant mutants of the Sabin strain of poliovirus type 3. Such mutants provide information about parts of the capsid that are important for functions blocked by the drugs, and also about pathways to drug resistance. Amino-acid substitutions allowing virus to produce progeny in the presence of drug were mapped to 13 different residues occupying three distinct locations: (I) the canyon base; (II) the lining of the drug-binding pocket; and (III) the base of the protomer. These loci might be thought of as action points for transmitting the uncoating signal from receptor, through the pocket, and to the base of the protomer. All of the mutations in a special class of drug-dependent mutants were clustered at site (III) and all were hyperlabile, i.e., uncoated spontaneously (without receptor) at growth temperature unless prevented from doing so by the presence of drug in the pocket. Thus, site (III) seems to represent a kind of thermostat which regulates the temperature at which the uncoating transition (release of VP4 to form A particles) is triggered.

17.
Ann Trop Med Parasitol ; 83(3): 263-9, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2513787

RESUMO

In Martinique, intestinal schistosomiasis was discovered at the beginning of this century. The intermediate host snail, Biomphalaria glabrata, was considered in the past as a common species in the different habitats of the island, but during the last decade it has been found only in water-cress beds. Several of these water-cress cultures contained mixed populations of B. glabrata and B. straminea. Moreover, these habitats also constituted transmission sites for Schistosoma mansoni infection. In 1979 the thiarid snail Thiara ( = Melanoides) tuberculata was discovered in Madame river, Fort-de-France, and in the following years at other sites. In 1983 a programme of biological control using this snail was started in two groups of water-cress beds. In 1981-1982 the study site, Roxelane valley, sheltered important populations of B. glabrata (45-256 individuals/m2) and of B. straminea (2-30 ind./m2). In January 1983 the competitor T. tuberculata was introduced into the two groups of water-cress beds (1.3 and 1.7 ind./m2 respectively) and during subsequent years snail population sampling was carried out. The results showed rapid colonization by the competitor snail, whose densities reached 178 and 325 ind./m2 in November 1983 and a maximum of 9941 and 13,388 ind./m2 in October 1984. During that time, B. glabrata populations declined: 153 and 41 ind./m2 in November 1983, 4 and 0 ind./m2 in October 1984, and 0 ind./m2 in the two groups of water-cress beds in October 1985. A similar phenomenon was observed for B. straminea. Since October 1985 neither planorbid species has been found by exhaustive sampling of the habitats.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Biomphalaria/crescimento & desenvolvimento , Vetores de Doenças , Controle Biológico de Vetores , Esquistossomose mansoni/prevenção & controle , Caramujos/crescimento & desenvolvimento , Animais , Martinica , Esquistossomose mansoni/transmissão
18.
J Virol ; 34(2): 431-7, 1980 May.
Artigo em Inglês | MEDLINE | ID: mdl-6246274

RESUMO

Virions of Rous-associated virus type 61 contain a previously unrecognized p19-related protein, called p19f, which comigrates with gag protein p12 during electrophoresis in sodium dodecyl sulfate-polyacrylamide gels but can be separated by gel filtration chromatography in 6 M guanidine hydrochloride. It is shown that the existence of p19f accounts for the earlier inability to order p27 and p12 by the pactamycin mapping procedure. Remapping with pactamycin by using methods which take this new protein into account yielded a gag gene order of NH2-p219-p27-p12-p15-COOH. It also confirmed earlier positions for the env and pol genes and placed unclassified protein p10 near a translational initiation site. The pactamycin-derived mapping position of p12 differs from reports based on tryptic analysis. An analysis of procedural shortcomings emphasizes the need for more definitive determinations of the avian gag gene order.


Assuntos
Vírus da Leucose Aviária/genética , Genes Virais , Proteínas Virais/genética , Vírus da Leucose Aviária/análise , Cromatografia em Gel , Eletroforese em Gel de Poliacrilamida , Pactamicina/farmacologia , Biossíntese de Proteínas , Proteínas Virais/análise
19.
J Virol ; 68(12): 8193-201, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7966611

RESUMO

We have previously described the use of an uncoating inhibitor, WIN 51711, to select drug-resistant mutants of the Sabin strain of poliovirus type 3. Two-thirds of the mutants proved to be dependent on the drug for plaque formation because of extreme thermolability (A. G. Mosser and R. R. Rueckert, J. Virol. 67:1246-1254, 1993). Here we report the responsible mutations; all were traced to single amino acid substitutions. Mutations conferring dependence and thermolability occurred in all four capsid proteins (VP1 to VP4), but all were clustered near residue 53 of VP4 at the inner capsid surface. Amino acid substitutions of the remaining non-drug-dependent mutants were mapped to three distinct loci: (i) on or near the inner capsid surface, at VP4 residue 46 or VP1 residue 129, in the vicinity of the drug dependence substitutions; (ii) at residues 192, 194, and 260 in the lining of the VP1 beta barrel, which is the drug-binding site; and (iii) at VP1 residue 105 on the edge of the canyon surrounding the fivefold axis of symmetry, the putative receptor-binding site. All of the mutations increased the eclipse rate of cell-attached virus. Such mutants help identify parts of the capsid that play a role in viral uncoating functions.


Assuntos
Capsídeo/química , Resistência Microbiana a Medicamentos/genética , Proteínas de Membrana , Mutação Puntual , Poliovirus/genética , Sequência de Aminoácidos , Antivirais/farmacologia , Sítios de Ligação , Capsídeo/genética , Capsídeo/metabolismo , Células HeLa , Humanos , Isoxazóis/farmacologia , Cinética , Modelos Biológicos , Modelos Moleculares , Poliovirus/efeitos dos fármacos , Poliovirus/metabolismo , Conformação Proteica , Estrutura Secundária de Proteína , RNA Viral/química , RNA Viral/metabolismo , Receptores Virais/fisiologia , Temperatura , Ensaio de Placa Viral
20.
J Virol ; 21(1): 105-12, 1977 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-189060

RESUMO

Previously it was shown that the host-range gene of the Bratislava strain of avain sarcoma virus (B77 virus) spontaneously mutates with a very high rate. The wild-type B77 virus called B77 virus-II, mutates either to virus that efficiently infects duck cells (B77 virus-III) or to virus that does not mutate to the ability to infect duck cells (B77 virus-I) (Zarling and Temin, 1976). No significant differences in either the virion envelope glycoproteins or other major virion proteins were detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. However, pseudotypes of B77 virus-I with proteins of a transformation-defective mutant of B77 virus-III formed foci efficiently in duck cells. An alteration in the envelope protein of B77 virus-I was demonstrated by experiments in which B77 firus-I was fused into duck cells with UV-irradiated Sendai virus and formed foci. Neutralization experiments further demonstrated that B77 virus host-range mutants have altered type-specific envelope antigens. Thus, the spontaneous mutations in the host-range gene of B77 virus involve changes in the type-specific virion envelope antigen.


Assuntos
Antígenos Virais , Vírus do Sarcoma Aviário/crescimento & desenvolvimento , Mutação , Proteínas Virais/imunologia , Animais , Antígenos Virais/análise , Vírus da Leucose Aviária/crescimento & desenvolvimento , Vírus da Leucose Aviária/imunologia , Vírus do Sarcoma Aviário/imunologia , Fusão Celular , Linhagem Celular , Transformação Celular Neoplásica , Patos , Genes , Testes de Neutralização , Vírus da Parainfluenza 1 Humana/crescimento & desenvolvimento , Proteínas Virais/análise , Replicação Viral
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