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1.
Ann Pharm Fr ; 78(2): 189-197, 2020 Mar.
Artigo em Francês | MEDLINE | ID: mdl-31806152

RESUMO

INTRODUCTION: The Medical Device Committee (CODIMS) evaluates all innovative medical devices (MD) before their introduction in the hospitals of the Assistance publique-hôpitaux de Paris (AP-HP). At the national level, the Medical Device and Health Technology Evaluation Committee (CNEDiMTS) provides recommendation for MD with respects to reimbursement by the National Health Insurance Fund. The aim of this study is to compare the recommendations of both committees and to analyze their timing on a six-year period. MATERIAL AND METHOD: We selected all innovative MD assessed by the CODIMS between 2013 and 2018. We retrieved all the recommendations for these MD from the CNEDiMTS. We performed quantitative and qualitative analysis of data collected. RESULTS: On 30 innovative MD assessed by both the CODIMS and the CNEDiMTS, 11 (37%) evaluations were performed by the CODIMS before the CNEDiMTS evaluation. They occurred approximately a year before the CNEDiMTS recommendation (an average of 378 days). Among the 25 MD with a recommendation of both committees, the two opinions were consistent in 88 per cent of all cases. DISCUSSION/CONCLUSION: This study highlights that there is a good consistency between the recommendations of both committees. This suggests that the MD evaluations conducted at the hospital level are relevant and timely. Finally, a better coordination between the national and local levels should be promoted for the MD assessment.


Assuntos
Equipamentos e Provisões/normas , Avaliação da Tecnologia Biomédica , França , Hospitais , Humanos , Reembolso de Seguro de Saúde , Programas Nacionais de Saúde
2.
Ann Pharm Fr ; 76(3): 228-234, 2018 May.
Artigo em Francês | MEDLINE | ID: mdl-29397920

RESUMO

OBJECTIVES: Single use patient-specific instruments (PSI) for total knee prosthesis are introduced as a new alternative to conventional ancillaries and computer assisted surgery by improving implants positioning. An exhaustive review was carried out to identify their specific characteristics, with their advantages and disadvantages. METHODS: Medical devices suppliers were consulted in 2015 for reviewing their PSI. Their technical, clinical and economic data were compared. The results had been submitted to an orthopaedics expert commission of our university hospital for clinical and financial opinion. RESULTS: Ten companies have provided the documentation for the analysis. PSI are manufactured by suppliers using a three dimensional printing method based on CT scans or MRI images. PSI are produced according to the surgeon's preferences after a preliminary data check, which can be performed by the suppliers' engineers, the surgeon and automatic calculation. Five suppliers can produce sterile PSI with optional delivery of 3D bone models. According to the experts, the studies failed to demonstrate the superiority of a PSI or hospital economic gain. The prices listed remain high and operating room time is not always significantly reduced. CONCLUSIONS: With the development of personalized medicine, the role of PSI grows in importance. They facilitate the surgeon's work by fully respecting the anatomy. These systems offer an interesting perspective in their technical and pedagogical aspects. But it seems premature to take them into routine use given the low number of high-level studies that were currently done.


Assuntos
Prótese do Joelho/normas , Medicina de Precisão/métodos , Artroplastia do Joelho/normas , Humanos , Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética , Impressão Tridimensional , Tomografia Computadorizada por Raios X
3.
Ann Pharm Fr ; 76(2): 122-128, 2018 Mar.
Artigo em Francês | MEDLINE | ID: mdl-29203035

RESUMO

OBJECTIVES: Since 2009, single-use (SU) ancillaries for total knee arthroplasty (TKA) and total hip arthroplasty (THA) have been marketed to replace reusable ancillaries. The concept is not innovative but their use in orthopedics is still uncommon. An assessment has been done for the use of SU ancillary in Assistance publique-hôpitaux de Paris with the consequences for the patient, the surgeon and the hospital. METHODS: A technical and a clinical review has been done with those devices in 2015. The economic and organizational impacts were identified and submitted for opinion to committee experts in orthopedics. RESULTS: Three SU ancillaries are commercialized. No clinical studies are currently available. There is no reimbursement for SU ancillaries whereas reusable ancillaries are included in prosthesis reimbursement price. Although SU ancillaries (TKA and THA) saving costs for sterilization, the annual additional budget estimated for their purchase would approximately be 2.5 times higher. Nevertheless, indirect savings could be also considered in the long-term period (global costs for sterilization, volume effect…). For the same quality, according to the experts, organizational impacts are low for the patient and the surgeon but potentially important for the hospital, the nursing and pharmaceutical staff, and logistical activities. CONCLUSIONS: On logistic, clinical and financial aspects, SU ancillaries need more evaluation. The switch to SU ancillaries allows saving sterilization costs and time, and provided an immediate mobilization of the equipment but their interest must be demonstrated by clinical and economic data.


Assuntos
Equipamentos Descartáveis/economia , Reutilização de Equipamento/economia , Ortopedia/estatística & dados numéricos , Instrumentos Cirúrgicos/economia , Custos e Análise de Custo , Humanos , Reembolso de Seguro de Saúde , Procedimentos Ortopédicos/instrumentação
4.
Ann Pharm Fr ; 74(6): 473-481, 2016 Nov.
Artigo em Francês | MEDLINE | ID: mdl-27139164

RESUMO

INTRODUCTION: The Medical Devices Committee (CODIMS) of the Assistance publique-Hôpitaux de Paris (AP-HP) is responsible for deciding whether innovative and costly sterile medical devices (SMD) should be adopted for the AP-HP network and for issuing recommendations on their proper use. The aim of this study was to qualify retrospectively the level of evidence of clinical studies used for the device evaluations by the CODIMS in 2012 and 2013 and to analyze the relationship between levels of evidence and decisions. MATERIAL AND METHOD: Executive summaries written in 2012 and 2013 about studied SMD was analyzed and the level of evidence of clinical studies used was qualified in high/low levels of evidence according to the scale of Sackett et al. Then, levels of evidence were correlated to decisions published by the CODIMS. RESULTS: Sixty-one files of SMD (72.1% of implantable MD) have been evaluated (225 clinical studies). Among them, only 28% of clinical studies had a high level of evidence (and 28.6% of MD at-risk) and 18% did not have any clinical studies. The CODIMS delivered an unfavourable opinion for 16 SMD: only 28 clinicals studies were available for evaluation. Among these, only 6 studies had a high level of evidence. DISCUSSION ET CONCLUSION: The amount and level of evidence of clinical studies is naturally correlated to admittance of SMD. These findings suggest that the clinical evidence used to demonstrate safety and efficacy for high-risk medical devices is based on clinical studies with poor quality data, making more difficult the evaluation of SMD in hospital. The development of a multi-criteria tool to help decision-making would improve the process of SMD evaluation by the CODIMS.


Assuntos
Administração Hospitalar , Avaliação da Tecnologia Biomédica , Equipamentos e Provisões , Medicina Baseada em Evidências , Humanos , Paris , Estudos Retrospectivos
6.
Med Mal Infect ; 43(3): 114-7, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23498136

RESUMO

INTRODUCTION: Vaccine recommendations are the same for healthcare students than for other health care workers. The aim of this study was to describe mandatory and recommended vaccinal coverage and evaluate the benefit of systematic monitoring by a medical team in the Lille Medical School. POPULATION AND METHODS: A survey was performed from June 2011 to August 2011 on all students in the first year of Health Care Studies. The personal immunization record was considered as evidence of vaccination. The reference vaccinal schedule was the one recommended by the French High Council for Public Health in 2011. RESULTS: We analyzed the personal immunization records of 553 students. The vaccination coverage was 96.7% (535) for DTP, 74.7% (413) for hepatitis B, and 92.2% (510) of the students had a tuberculin test result. Concerning the recommended vaccinations, 78% (431) were covered for measles, and 78.9% (436) had a history of either chickenpox or its immunization. About 72.7% (402) of students were vaccinated for Haemophilus influenzae and Bordetella pertussis. Respectively, 24.2% (134) and 81% (448) had previously been vaccinated for Neisseria meningitis and tuberculosis. The monitoring of students allowed improving hepatitis B vaccination coverage by 22.28% (123). The student's vaccinal coverage was still inadequate for hepatitis B and measles. The systematic monitoring allowed significantly improving vaccinal coverage for hepatitis B.


Assuntos
Estudantes de Ciências da Saúde/estatística & dados numéricos , Vacinação/estatística & dados numéricos , Adolescente , Vacinas Bacterianas , Feminino , França , Pesquisas sobre Atenção à Saúde , Humanos , Masculino , Prontuários Médicos , Teste Tuberculínico/estatística & dados numéricos , Vacinação/legislação & jurisprudência , Vacinação/normas , Vacinas Virais , Adulto Jovem
8.
Mutat Res ; 435(2): 111-9, 1999 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-10556591

RESUMO

Individuals with Xeroderma pigmentosum (XP) syndrome have a genetic predisposition to sunlight-induced skin cancer. Genetically different forms of XP have been identified by cell fusion. Cells of individuals expressing the classical form of XP (complementation groups A through G) are deficient in the nucleotide excision repair (NER) pathway. In contrast, the cells belonging to the variant class of XP (XPV) are NER-proficient and are only slightly more sensitive than normal cells to the killing action of UV light radiation. The XPV fibroblasts replicate damaged DNA generating abnormally short fragments either in vivo [A.R. Lehmann, The relationship between pyramidine dimers and replicating DNA in UV-irradiated human fibroblasts, Nucleic Acids Res. 7 (1979) 1901-1912; S.D. Park, J.E. Cleaver, Postreplication repair: question of its definition and possible alteration in Xeroderma pigmentosum cell strains, Proc. Natl. Acad. Sci. U.S.A. 76 (1979) 3927-3931.] or in vitro [S.M. Cordeiro, L.S. Zaritskaya, L.K. Price, W.K. Kaufmann, Replication fork bypass of a pyramidine dimer blocking leading strand DNA synthesis, J. Biol. Chem. 272 (1997) 13945-13954; D.L. Svoboda, L.P. Briley, J.M. Vos, Defective bypass replication of a leading strand cyclobutane thymine dimer in Xeroderma pigmentosum variant cell extracts, Cancer Res. 58 (1998) 2445-2448; I. Ensch-Simon, P.M. Burgers, J.S. Taylor, Bypass of a site-specific cis-syn thymine dimer in an SV40 vector during in vitro replication by HeLa and XPV cell-free extracts, Biochemistry 37 (1998) 8218-8226.], suggesting that in XPV cells, replication has an increased probability of being blocked at a lesion. Furthermore, extracts from XPV cells were found to be defective in translesion synthesis [A. Cordonnier, A.R. Lehmann, R.P.P. Fuchs, Impaired translesion synthesis in Xeroderma pigmentosum variant extracts, Mol. Cell. Biol. 19 (1999) 2206-2211.]. Recently, Masutani et al. [C. Masutani, M. Araki, A. Yamada, R. Kusomoto, T. Nogimori, T. Maekawa, S. Iwai, F. Hanaoka, Xeroderma pigmentosum variant (XP-V) correcting protein from HeLa cells has a thymine dimer bypass DNA polymerase activity, EMBO J. 18 (1999) 3491-3501.] have shown that the XPV defect can be corrected by a novel human DNA polymerase, homologue to the yeast DNA polymerase eta, which is able to replicate past cyclobutane pyrimidine dimers in DNA templates. This review focuses on our current understanding of translesion synthesis in mammalian cells whose defect, unexpectedly, is responsible for the hypermutability of XPV cells and for the XPV pathology.


Assuntos
Dano ao DNA/genética , Replicação do DNA/genética , Xeroderma Pigmentoso/genética , Xeroderma Pigmentoso/patologia , Animais , Humanos
9.
Mol Cell Biol ; 19(3): 2206-11, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10022907

RESUMO

Xeroderma pigmentosum variant (XPV) cells are characterized by a cellular defect in the ability to synthesize intact daughter DNA strands on damaged templates. Molecular mechanisms that facilitate replication fork progression on damaged DNA in normal cells are not well defined. In this study, we used single-stranded plasmid molecules containing a single N-2-acetylaminofluorene (AAF) adduct to analyze translesion synthesis (TLS) catalyzed by extracts of either normal or XPV primary skin fibroblasts. In one of the substrates, the single AAF adduct was located at the 3' end of a run of three guanines that was previously shown to induce deletion of one G by a slippage mechanism. Primer extension reactions performed by normal cellular extracts from four different individuals produced the same distinct pattern of TLS, with over 80% of the products resulting from the elongation of a slipped intermediate and the remaining 20% resulting from a nonslipped intermediate. In contrast, with cellular extracts from five different XPV patients, the TLS reaction was strongly reduced, yielding only low amounts of TLS via the nonslipped intermediate. With our second substrate, in which the AAF adduct was located at the first G in the run, thus preventing slippage from occurring, we confirmed that normal extracts were able to perform TLS 10-fold more efficiently than XPV extracts. These data demonstrate unequivocally that the defect in XPV cells resides in translesion synthesis independently of the slippage process.


Assuntos
Dano ao DNA , Xeroderma Pigmentoso/genética , Extratos Celulares , Primers do DNA , DNA de Cadeia Simples , Teste de Complementação Genética , Humanos , Xeroderma Pigmentoso/patologia
10.
J Virol ; 71(7): 5652-7, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9188643

RESUMO

We had previously identified a new family of human endogenous retrovirus-like elements, the HERV-L elements (human endogenous retrovirus with leucine tRNA primer), whose pol gene was most closely related to that of the foamy viruses. HERV-L pol-related sequences were also detected in other mammalian species. The recent cloning of the mouse Fv1 gene (S. Best, P. Le Tissier, G. Towers, and J. P. Stoye, Nature 382:826-829, 1996) has shed light on another HERV-L domain--identified as a gag gene based on its location within the provirus--which was found to be 60% identical, at the nucleotide level, to the Fv1 open reading frame (ORF). We have now cloned the murine homolog of HERV-L which, in contrast to HERV-L, displays fully open reading frames in the gag and pol genes. Its predicted Gag protein shares 43% identity with the Fv1 ORF product. Moreover, the characteristic major homology region of the capsid subdomain can be identified within both proteins, thus strongly emphasizing the gag-like origin of Fv1.


Assuntos
Proteínas de Ciclo Celular , Genes gag , Proteínas de Neoplasias , Proteínas/genética , Retroviridae/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , DNA Viral , Humanos , Camundongos , Dados de Sequência Molecular , Fases de Leitura Aberta , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
11.
J Virol ; 69(9): 5890-7, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7543594

RESUMO

A new class of reverse transcriptase coding sequences was detected in reverse-transcribed RNAs from human placenta by polymerase chain amplification with primers in highly conserved regions of the pol gene of mammalian retroviruses and retrotransposons. Using one of these novel sequences as a probe to screen a human genomic library, we isolated retrovirus-like elements bordered by long terminal repeats and having a potential leucine tRNA primer-binding site. Determination of the complete nucleotide sequence (6,591 bp) of one of these elements, termed HERV-L (for human endogenous retrovirus with leucine tRNA primer), revealed domains of amino acid similarities to retroviral reverse transcriptase and integrase proteins. In addition, a region with homologies to dUTPase proteins was found unexpectedly downstream from the integrase domain. Amino acid sequence and phylogenetic analysis indicate that the HERV-L pol gene is related to that of foamy retroviruses. HERV-L-related sequences are detected in several mammalian species and have expanded in primate and mouse genomes up to 100 to 200 copies.


Assuntos
Genes pol , Filogenia , Retroviridae/genética , Retroviridae/isolamento & purificação , Spumavirus/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Primers do DNA , DNA Viral/análise , Biblioteca Genômica , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , DNA Polimerase Dirigida por RNA/química , DNA Polimerase Dirigida por RNA/genética , Homologia de Sequência de Aminoácidos , Especificidade da Espécie
12.
Adv Contracept ; 11(2): 165-72, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7491857

RESUMO

The aim of the study was to check, in a European environment, the practical efficiency and the acceptability of a recent natural family planning (NFP) method. This method includes a double check to detect the beginning as well as the end of the fertile phase of the menstrual cycle. Up to now, 71 women of reproductive age have been registered. They agreed to provide their symptothermal charts and related information. Average age is 32 years. Average fertility is 2 children/woman. Fifty-nine percent of the participants have a professional occupation. The same percentages are found in those accepting a contraceptive method (oral contraceptives or intrauterine devices). Until today 1240 cycles (103 women-years) of experience have been gathered. The average participation was 17.5 cycles/woman. No method failure has been reported. One unintended pregnancy due to unprotected sexual intercourse during the fertile phase occurred (user failure). Overall Pearl Index (PI) was 0.96. In 84% of the cycles, no protected intercourse was reported (NFP only). According to PI, practical efficiency of the NFP method analyzed was 1.31. Sexual abstinence during the fertile phase was found in 71.4% of the cycles.


Assuntos
Temperatura Corporal/fisiologia , Muco do Colo Uterino/fisiologia , Serviços de Planejamento Familiar/normas , Fertilidade/fisiologia , Abstinência Sexual , Adolescente , Adulto , Bélgica , Política de Planejamento Familiar , Serviços de Planejamento Familiar/métodos , Feminino , Humanos , Ciclo Menstrual/fisiologia , Pessoa de Meia-Idade , Ovulação/fisiologia , Participação do Paciente , Inquéritos e Questionários
13.
J Virol ; 67(10): 6253-8, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8371358

RESUMO

The fourth conserved region (C4) of human immunodeficiency virus type 1 (HIV-1) surface glycoprotein has been shown to participate in CD4 binding and to influence viral tropism (A. Cordonnier, L. Montagnier, and M. Emerman, Nature [London] 340:571-574, 1989). To define the role of the corresponding region of HIV-2, we introduce single amino acid changes into the C4 sequence of HIV-2ROD. The effects of these mutations on glycoprotein function and on virus infectivity have been examined. We have shown that the tryptophan residue at position 428 is necessary primarily for CD4 binding. The isoleucine residue at position 421 is necessary for the establishment of productive infection in the promonocytic cell line U937, while it is dispensable to some extent for infection of primary T lymphocytes or the lymphocytic cell line SUP-T1. This replication defect correlated with the failure of the Ile-421-to-Thr (Ile-421-->Thr) mutant glycoprotein to form syncytia in U937 cells. DNA analysis of revertant viruses revealed that a strong selective pressure was exerted on residue 421 of the surface glycoprotein to allow HIV-2 infection of U937 cells. These results demonstrate that this region of HIV-2 plays an important role in determining fusion efficiency in a cell-dependent manner and consequently can influence viral tropism.


Assuntos
Sequência Conservada , HIV-2/metabolismo , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Antígenos CD4/metabolismo , Linhagem Celular , Códon/genética , Cisteína/metabolismo , DNA Viral/metabolismo , Células Gigantes , Repetição Terminal Longa de HIV , HIV-2/genética , Células HeLa , Humanos , Fusão de Membrana , Metionina/metabolismo , Mutagênese Sítio-Dirigida , Fenótipo , Plasmídeos , Proteínas Recombinantes de Fusão/metabolismo , Transfecção , beta-Galactosidase/metabolismo
14.
AIDS Res Hum Retroviruses ; 9(8): 787-93, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8217346

RESUMO

The envelope (Env) protein from HIV-1 is the focus of several vaccine trials in humans. It could be considered for the optimization of Env vaccinal preparations to add within the molecule defined epitopes, for instance epitopes conserved among viral isolates from HIV-1, such as from Gag or Nef proteins. As a first step to this approach, we have constructed by in vitro mutagenesis HIV-1(LAI) Env gp120 molecules in which a 12-amino acid sequence in the first (V1) or the third (V3) hypervariable region was substituted by the hemagglutinin (HA) 307-318 peptide from the influenza virus, a dominant T helper cell epitope in humans. The proteins were produced by recombinant vaccinia viruses. They had kept their structural properties in terms of serological recognition and binding to CD4. Of note, we observed that the gp120 protein substituted in the V1 domain elicited a stronger serological immune response in mice compared to native or V3 substituted gp120. This indicates that gp120 can accommodate large substitutions without major structural perturbations and that, on the contrary, some of them could prove beneficial in terms of immunogenicity.


Assuntos
Proteína gp120 do Envelope de HIV/imunologia , Sequência de Aminoácidos , Animais , Antígenos CD4/metabolismo , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia
15.
Virology ; 192(1): 33-7, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8517024

RESUMO

During the phenotypic analysis of mutations in the HIV-2 envelope protein (gp140), we have identified a mutant that expresses high levels of gp140 in the absence of the Rev protein. This mutant was obtained by deletion of a 190-base pair fragment at the end of the env coding region. Northern blot analysis of RNAs produced by transfected HeLa cells showed that this fragment inhibits the cytoplasmic transport of unspliced env-specific RNAs in the absence of Rev. The "inhibitory element" was only active in the sense orientation and appeared to be specific for unspliced HIV-2 env RNAs, suggesting that it may have an important regulatory role for HIV-2 expression.


Assuntos
Núcleo Celular/metabolismo , Genes env , HIV-2/genética , RNA Viral/metabolismo , Compartimento Celular , Produtos do Gene rev/metabolismo , Células HeLa , Humanos , Splicing de RNA , RNA Mensageiro/metabolismo , Sequências Reguladoras de Ácido Nucleico , Produtos do Gene rev do Vírus da Imunodeficiência Humana
16.
J Gen Virol ; 73 ( Pt 7): 1773-80, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1629702

RESUMO

The human immunodeficiency virus type 1 (HIV-1) regulatory protein Rev stimulates expression of structural viral proteins via a target response element (RRE) located within gag-pol and env mRNAs. To analyse the HIV-2 Rev trans-activation effect on the expression of the envelope protein, we cloned a functionally active HIV-2 rev cDNA and showed that it contained four exons. Using transient expression assays, we mapped a 353 bp RRE fragment within the env gene of HIV-2 on which both HIV-1 and HIV-2 Rev could act. Interestingly, smaller fragments suppressed the use of additional splice sites within the env gene and caused envelope protein expression independent of Rev.


Assuntos
Mapeamento Cromossômico , Genes Virais , Genes rev , Proteína gp120 do Envelope de HIV/biossíntese , HIV-2/genética , Sequência de Bases , Clonagem Molecular , Produtos do Gene rev/biossíntese , HIV-1/genética , Dados de Sequência Molecular , Ativação Viral , Produtos do Gene rev do Vírus da Imunodeficiência Humana
18.
J Virol ; 63(10): 4464-8, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2550679

RESUMO

Sequence comparison of the human immunodeficiency virus type 1 and type 2 env genes revealed the presence of six linear regions in the extracellular glycoprotein that are highly conserved. To investigate the functional significance of these regions, we made short deletions in each and assayed the ability of the mutated proteins to bind CD4 antigen. Small deletions in four of the highly conserved regions drastically reduced receptor binding. Some deletions interfered with the maturation of the envelope glycoprotein, but maturation did not necessarily correlate with the ability to bind CD4 antigen.


Assuntos
HIV/genética , Receptores Virais/metabolismo , Proteínas dos Retroviridae/metabolismo , Proteínas do Envelope Viral/metabolismo , Sequência de Aminoácidos , Glicosilação , Proteína gp120 do Envelope de HIV , Proteína gp160 do Envelope de HIV , Mutação , Receptores de HIV , Proteínas dos Retroviridae/análise , Proteínas dos Retroviridae/genética , Vaccinia virus/genética , Proteínas do Envelope Viral/análise , Proteínas do Envelope Viral/genética
20.
Nature ; 340(6234): 571-4, 1989 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-2475780

RESUMO

Infection by the human immunodeficiency virus (HIV) is initiated by the binding of its extracellular envelope glycoprotein, gp120, to the CD4 antigen on target cells. To map the residues of the HIV-1 glycoprotein that are critical for binding and to analyse the effects of binding on viral infectivity, we created 15 mutations in a region of gp120 that is important for binding to CD4 (refs 4,5). We find that substitution of a single amino acid (tryptophan at position 432) can abrogate CD4 binding and that virus carrying this mutation is non-infectious. By contrast, other amino-acid changes in the same region do not affect CD4 binding but restrict viral tropism: virions containing isoleucine substitutions at position 425 lose their ability to infect a monocyte cell line (U937 cells) but can still infect T-lymphocyte cell lines (CEM, SUP-T1) and activated human peripheral blood lymphocytes. These results indicate that cellular tropism of HIV can be influenced by a single amino-acid change in gp120.


Assuntos
HIV/patogenicidade , Receptores Virais/metabolismo , Proteínas dos Retroviridae/genética , Proteínas do Envelope Viral/genética , HIV/metabolismo , Proteína gp120 do Envelope de HIV , Mutação , DNA Polimerase Dirigida por RNA/análise , Receptores de HIV
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