Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 33
Filtrar
1.
J Stomatol Oral Maxillofac Surg ; 124(1S): 101308, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36220549

RESUMEN

OBJECTIVE: To compare the treatment outcomes and effectiveness of Anterior Maxillary Distraction (AMD) with the LeFort I Osteotomy and Total Maxillary Distraction Osteogenesis (TMDO) to treat cleft maxillary hypoplasia. METHODS: (PROSPERO CRD42020223345) Thorough electronic search of seven databases, unpublished gray literature, and a hand search of the relevant studies reference lists was done. Studies assessing mid-facial skeletal, dentoalveolar, and soft-tissue outcomes of AMD in patients >8 years of age, hypoplastic cleft maxilla, and with either TMDO/LeFort 1/ both as control groups were included. Seven included articles were assessed for the study characteristics and qualitative synthesis. Three studies were analyzed quantitatively using the RevMan 5.4 software. The quality of studies was assessed using Cochrane ROB2 and the overall certainty of evidence using GRADE. RESULTS: AMD was performed in 241 subjects, LeFort 1 in 145 subjects, and TMDO in 42 subjects. Maxillary advancement for AMD and LeFort 1 groups showed no statistically significant difference (Mean Difference, MD -0.64°) while TMDO showed statistically significant advancement than AMD (MD -1.44°). Statistically significant upward rotation of anterior maxilla was noted with AMD (MD -6.15 degrees) than Lefort 1. Upper incisor inclination improved in both AMD and TMDO groups (MD 1.5°). Improvement in the maxilla-mandibular relationship, convexity of face, lip and nose, and marked dentoalveolar changes in overjet and upper incisor position were noted in all the three groups. Discernible airway alterations were noted in LeFort 1 and TMDOs. Total relapse was the least with AMD. CONCLUSION: Distraction osteogenesis exhibited better dento-skeletal outcomes and minor skeletal relapse than LeFort 1. TMDO is a preferred modality in treating severe maxillary hypoplasia associated with CLP than AMD. Further long-term prospective comparative studies are required, possibly involving the patient-centric merits.


Asunto(s)
Labio Leporino , Fisura del Paladar , Osteogénesis por Distracción , Humanos , Labio Leporino/cirugía , Labio Leporino/complicaciones , Fisura del Paladar/cirugía , Fisura del Paladar/complicaciones , Estudios Prospectivos , Cefalometría , Maxilar/cirugía , Osteotomía Le Fort , Recurrencia
2.
Bone Joint J ; 101-B(5): 582-588, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31039037

RESUMEN

AIMS: The aims of this study were to report the efficacy of revision surgery for patients with co-infective bacterial and fungal prosthetic joint infections (PJIs) presenting to a single institution, and to identify prognostic factors that would guide management. PATIENTS AND METHODS: A total of 1189 patients with a PJI were managed in our bone infection service between 2006 and 2015; 22 (1.85%) with co-infective bacterial and fungal PJI were included in the study. There were nine women and 13 men, with a mean age at the time of diagnosis of 64.5 years (47 to 83). Their mean BMI was 30.9 kg/m2 (24 to 42). We retrospectively reviewed the outcomes of these PJIs, after eight total hip arthroplasties and 14 total knee arthroplasties. The mean clinical follow-up was 4.1 years (1.4 to 8.8). RESULTS: The median number of risk factors for PJI was 5.5 (interquartile range (IQR) 3.25 to 7.25). All seven patients who initially underwent debridement and implant retention (DAIR) had a recurrent infection that led to a staged revision. All 22 patients underwent the first of a two-stage revision. None of the nine patients with negative tissue cultures at the second stage had a recurrent infection. The rate of recurrent infection was significantly higher in the presence of multidrug-resistant bacteria (p = 0.007), a higher C-reactive protein (CRP) at the time of presentation (p = 0.032), and a higher number of co-infective bacterial organisms (p = 0.041). The overall rate of eradication of infection after two and five years was 50% (95% confidence interval (CI) 32.9 to 75.9) and 38.9% (95% CI 22.6 to 67), respectively. CONCLUSION: The risk of failure to eradicate infection with the requirement of amputation associated with this diagnosis is much higher than in patients with PJI without bacterial and fungal co-infection, and this risk is heightened when the fungal organism is joined by polymicrobial and multidrug-resistant bacterial organisms. Cite this article: Bone Joint J 2019;101-B:582-588.


Asunto(s)
Infecciones Bacterianas/complicaciones , Micosis/complicaciones , Infecciones Relacionadas con Prótesis/cirugía , Reoperación/métodos , Anciano , Anciano de 80 o más Años , Antibacterianos/uso terapéutico , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Infecciones Bacterianas/cirugía , Coinfección , Femenino , Humanos , Masculino , Persona de Mediana Edad , Micosis/cirugía , Pronóstico , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Infecciones Relacionadas con Prótesis/microbiología , Estudios Retrospectivos , Factores de Riesgo , Análisis de Supervivencia
3.
NPJ Prim Care Respir Med ; 28(1): 44, 2018 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-30470741

RESUMEN

COPD self-management reduces hospital admissions and improves health-related quality of life (HRQoL). However, whilst most patients are managed in primary care, the majority of self-management trials have recruited participants with more severe disease from secondary care. We report the findings of a systematic review of the effectiveness of community-based self-management interventions in primary care patients with COPD. We systematically searched eleven electronic databases and identified 12 eligible randomised controlled trials with seven included in meta-analyses for HRQoL, anxiety and depression. We report no difference in HRQoL at final follow-up (St George's Respiratory Questionnaire total score -0.29; 95%CI -2.09, 1.51; I2 0%), nor any difference in anxiety or depression. In conclusion, supported self-management interventions delivered in the community to patients from primary care do not appear to be effective. Further research is recommended to identify effective self-management interventions suitable for primary care populations, particularly those with milder disease.


Asunto(s)
Atención Primaria de Salud , Enfermedad Pulmonar Obstructiva Crónica/terapia , Automanejo , Servicios de Salud Comunitaria , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
4.
Herz ; 38(4): 382-6, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23695652

RESUMEN

In patients with stable ischemic heart disease (SIHD), myocardial revascularization should be performed to either improve survival or improve symptoms and functional status among patients who are not well controlled with optimal medical therapy (OMT). A general consensus exists on the core elements of OMT, which include both lifestyle intervention and intensive secondary prevention with proven pharmacotherapies. By contrast, however, there is less general agreement as to what constitutes the optimal approach to revascularization in SIHD patients. The COURAGE and FAME 2 randomized trials form the foundation of the current clinical evidence base and raise the important question: "What is the impact of myocardial ischemia on myocardial revascularization in stable ischemic heart disease?"


Asunto(s)
Enfermedad de la Arteria Coronaria/mortalidad , Enfermedad de la Arteria Coronaria/cirugía , Isquemia Miocárdica/mortalidad , Isquemia Miocárdica/cirugía , Revascularización Miocárdica/mortalidad , Complicaciones Posoperatorias/mortalidad , Causalidad , Comorbilidad , Humanos , Prevalencia , Factores de Riesgo , Tasa de Supervivencia , Resultado del Tratamiento
5.
Meat Sci ; 94(1): 47-54, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23376436

RESUMEN

The effects of post-processing treatments on sensory quality and reduction of Shiga toxigenic Escherichia coli (STEC) in three formulations of two types of dry-fermented sausage (DFS; salami and morr) were evaluated. Tested interventions provided only marginal changes in sensory preference and characteristics. Total STEC reductions in heat treated DFS (32°C, 6days or 43°C, 24h) were from 3.5 to >5.5 log from production start. Storing of sausages (20°C, 1month) gave >1 log additional STEC reduction. Freezing and thawing of sausages in combination with storage (4°C, 1month) gave an additional 0.7 to 3.0 log reduction in STEC. Overall >5.5 log STEC reductions were obtained after storage and freezing/thawing of DFS with increased levels of glucose and salt. This study suggests that combined formulation optimisation and post-process strategies should be applicable for implementation in DFS production to obtain DFS with enhanced microbial safety and high sensory acceptance and quality.


Asunto(s)
Escherichia coli , Manipulación de Alimentos/métodos , Microbiología de Alimentos , Congelación , Calor , Productos de la Carne/análisis , Toxinas Shiga , Animales , Bovinos , Comportamiento del Consumidor , Inocuidad de los Alimentos , Almacenamiento de Alimentos , Humanos , Productos de la Carne/microbiología , Productos de la Carne/normas , Ovinos , Porcinos
6.
Eur J Orthod ; 34(2): 198-201, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21320891

RESUMEN

The aim of this study was to evaluate the use of fluoride varnish as a prophylaxis method with self etching primer (SEP) and its comparison with pumice before orthodontic bonding. Thirty seven orthodontic patients participated in a prospective clinical trial. A split mouth technique was used in each patient, one quadrant was assigned to fluoride varnish and the contralateral quadrant to pumice prophylaxis. A total of 684 teeth were bonded with SEP (Transbond plus; 3M Unitek) and monitored for 6 months for bond failures. A total of 42 (6.1%) failures were recorded, 9 (2.6%) in the pumice group and 33 (9.6%) in the fluoride varnish group. Chi-square analysis was used to compare the number of bracket failures between the pumice and fluoride varnish groups and the number of patients in each group experiencing at least one bond failure. Statistically significant differences were found both in total number of bond failures (P < 0.001) and in the number of patients with bond failures (P < 0.05) between both groups. A significantly lower and clinically acceptable bond failure rate was observed with Transbond Plus self etching primer after pumice prophylaxis.


Asunto(s)
Cariostáticos/química , Recubrimiento Dental Adhesivo/métodos , Materiales Dentales/química , Profilaxis Dental/instrumentación , Fluoruros Tópicos/química , Soportes Ortodóncicos , Cementos de Resina/química , Silicatos/química , Diente Premolar/patología , Falla de Equipo , Humanos , Incisivo/patología , Mandíbula , Ensayo de Materiales , Maxilar , Estudios Prospectivos
7.
Vaccine ; 29(52): 9675-83, 2011 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-22008822

RESUMEN

13-Valent pneumococcal conjugate vaccine (PCV13) administered as a 4-dose series in infants, and as a toddler dose in infants previously vaccinated with PCV7 elicited comparable vaccine serotypes IgG responses to the seven common serotypes. PCV13 elicited functional responses to the six additional serotypes in both schedules after the toddler dose. The toddler dose boosted immune responses. The two regimens had comparable safety profiles. A toddler dose of PCV13 given in children previously vaccinated with PCV7 should be effective in preventing pneumococcal disease caused by common serotypes, providing protection against the additional serotypes, and supporting the transition from PCV7 to PCV13.


Asunto(s)
Inmunización Secundaria/métodos , Vacunas Neumococicas/efectos adversos , Vacunas Neumococicas/inmunología , Vacunación/métodos , Anticuerpos Antibacterianos/sangre , Femenino , Francia , Vacuna Neumocócica Conjugada Heptavalente , Humanos , Inmunoglobulina G/sangre , Lactante , Masculino , Vacunas Neumococicas/administración & dosificación
8.
Transplant Proc ; 39(3): 766-72, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17445595

RESUMEN

Polyclonal antibodies have been used in renal transplantation for the past four decades. Increasing knowledge regarding their varied mechanisms of action have confirmed their versatility in clinical practice. They can be used for induction, reversing acute rejections (especially those resistant to steroids), and possibly conferring an element of allotolerance, thereby reducing chronic allograft nephropathy. Their recent usage as IV bolus, single-dose, preoperative infusion as induction therapy in renal transplantation is an attractive and extremely cost-effective strategy, especially in a developing country such as India.


Asunto(s)
Anticuerpos/sangre , Trasplante de Riñón/inmunología , Rechazo de Injerto/inmunología , Humanos , Inmunosupresores/uso terapéutico , Tolerancia al Trasplante
9.
Antimicrob Agents Chemother ; 46(11): 3606-12, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12384372

RESUMEN

A part (12 kb) of a plasmid containing the beta-lactamase genes of Tn552, the disinfectant resistance gene qacA, and flanking DNA has been cloned from a Staphylococcus haemolyticus isolate and sequenced. This region was used to map the corresponding regions in six other multiresistant S. haemolyticus isolates of human and animal origin. The organizations of the genetic structures were almost identical in all isolates studied. The beta-lactamase and qacA genes from S. haemolyticus have >99.9% identities at the nucleotide level with the same genes from S. aureus, demonstrating that various staphylococcal species able to colonize animal and human hosts can exchange the genetic elements involved in resistance to antibiotics and disinfectants. The use of antibiotics and disinfectants in veterinary practice and animal husbandry may also contribute to the selection and maintenance of resistance factors among the staphylococcal species. Different parts of the 12-kb section analyzed had high degrees of nucleotide identity with regions from several other different Staphylococcus aureus plasmids. This suggests the contribution of interplasmid recombination in the evolutionary makeup of this 12-kb section involving plasmids that can intermingle between various staphylococcal species. The lateral spread of resistance genes between various staphylococcal species is probably facilitated by the generation of large multiresistance plasmids and the subsequent interspecies exchange of them.


Asunto(s)
Antiinfecciosos Locales/farmacología , Proteínas Bacterianas/genética , Proteínas de Transporte de Membrana/genética , Infecciones Estafilocócicas/microbiología , Staphylococcus haemolyticus/efectos de los fármacos , Staphylococcus haemolyticus/genética , beta-Lactamasas/genética , Animales , Clonación Molecular , ADN Bacteriano/genética , Desoxirribonucleasas de Localización Especificada Tipo II/genética , Farmacorresistencia Bacteriana Múltiple , Etidio/farmacología , Humanos , Hibridación de Ácido Nucleico , Plásmidos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
10.
Microb Drug Resist ; 7(1): 73-83, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11310806

RESUMEN

Quaternary ammonium compounds (QACs) are widely used as disinfectant in medical and food environments. There is a growing concern about the increasing incidence of disinfectant-resistant microorganisms from food. Disinfectant-resistant lactic acid bacteria (LAB) may survive disinfection and cause spoilage problems. Moreover, resistant LAB may potentially act as a reservoir for resistance genes. A total number of 320 LAB from food industry and meat were screened for resistance to the QAC benzalkonium chloride (BC). Out of 320 strains, five strains (1.5%) were considered to be resistant and 56 (17.5%) were tolerant to BC. The resistant strains were isolated from food processing equipment after disinfection. The resistant, tolerant, and some sensitive control bacteria were examined for susceptibility to 18 different antibiotics, disinfectants, and dyes using disc agar diffusion test and microdilution method. Little systematic cross-resistance between BC and any of the antimicrobial agents tested were detected except for gentamycin and chlorhexidine. A BC-tolerant strain was much easier to adapt to higher levels of BC as compared to a BC-sensitive strain. No known gram-positive QAC resistance genes (qacA/B, qacC, qacG, and qacH) were detected in the BC-resistant strains. Identification to species level of the BC-resistant isolates was carried out by comparative analysis of 16S-rDNA sequencing. In conclusion, resistance to BC is not frequent in LAB isolated from food and food environments. Resistance may occur after exposure to BC. The BC resistant isolates showed no cross-resistance with other antimicrobial compounds, except for gentamycin and chlorhexidine. Nevertheless, BC-resistant LAB may be isolated after disinfection and may contribute to the dissemination of resistance.


Asunto(s)
Bacterias/efectos de los fármacos , Bacterias/metabolismo , Desinfectantes/farmacología , Farmacorresistencia Microbiana , Microbiología de Alimentos , Ácido Láctico/metabolismo , Antiinfecciosos Locales/farmacología , Compuestos de Benzalconio/farmacología , Southern Blotting , ADN Bacteriano/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
11.
J Virol ; 75(2): 910-20, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11134304

RESUMEN

Protein-encoding nucleotide sequences of the N, P, M, F, H, and L genes were determined for a low-passage isolate of the Edmonston wild-type (wt) measles virus and five Edmonston-derived vaccine virus strains, including AIK-C, Moraten, Schwarz, Rubeovax, and Zagreb. Comparative analysis demonstrated a high degree of nucleotide sequence homology; vaccine viruses differed at most by 0. 3% from the Edmonston wt strain. Deduced amino acid sequences predicted substitutions in all viral polypetides. Eight amino acid coding changes were common to all vaccine viruses; an additional two were conserved in all vaccine strains except Zagreb. Comparisons made between vaccine strains indicated that commercial vaccine lots of Moraten and Schwarz had identical coding regions and were closely related to Rubeovax, while AIK-C and Zagreb diverged from the Edmonston wt along slightly different paths. These comparisons also revealed amino acid coding substitutions in Moraten and Schwarz that were absent from the closely related reactogenic Rubeovax strain. All of the vaccine viruses contained amino acid coding changes in the core components of the virus-encoded transcription and replication apparatus. This observation, combined with identification of noncoding region nucleotide changes in potential cis-acting sequences of the vaccine strains (C. L. Parks, R. A. Lerch, P. Walpita, H.-P. Wang, M. S. Sidhu, and S. A. Udem, J. Virol. 75:921-933, 2001), suggest that modulation of transcription and replication plays an important role in attenuation.


Asunto(s)
Genoma Viral , Virus del Sarampión/genética , Proteínas Virales/química , Proteínas Virales/genética , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Genes Virales , Humanos , Vacuna Antisarampión , Virus del Sarampión/química , Virus del Sarampión/clasificación , Virus del Sarampión/patogenicidad , Datos de Secuencia Molecular , Mutación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Vacunas Atenuadas
12.
J Virol ; 75(2): 921-33, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11134305

RESUMEN

The noncoding sequence of five Edmonston vaccine viruses (AIK-C, Moraten, Rubeovax, Schwarz, and Zagreb) and those of a low-passage Edmonston wild-type (wt) measles virus have been determined and compared. Twenty-one nucleotide positions were identified at which Edmonston wt and one or more vaccine strains differed. The location of some of these nucleotide substitutions suggests that they may influence the efficiency of mRNA synthesis, processing, and translation, as well as genome replication and encapsidation. Five nucleotide substitutions were conserved in all of the vaccine strains. Two of these were in the genomic 3'-terminal transcriptional control region and could affect RNA synthesis or encapsidation. Three were found within the 5'-untranslated region of the F mRNA, potentially altering translation control sequences. The remaining vaccine virus base changes were found in one to four vaccine strains. Their genomic localization suggests that some may modify cis-acting regulatory domains, including the Kozak consensus element of the P and M genes, the F gene-end signal, and the F mRNA 5'-untranslated sequence.


Asunto(s)
Genoma Viral , Vacuna Antisarampión , Virus del Sarampión/genética , ARN no Traducido/análisis , Regiones no Traducidas 5'/genética , Secuencia de Bases , ADN Intergénico , Regulación Viral de la Expresión Génica , Genes Reguladores , Humanos , Sarampión/virología , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Transcripción Genética , Proteínas Virales/genética
13.
Tidsskr Nor Laegeforen ; 121(27): 3201-6, 2001 Nov 10.
Artículo en Noruego | MEDLINE | ID: mdl-11876147

RESUMEN

BACKGROUND: Disinfectants are widely used in medicine, veterinary medicine, and the food processing industry. Increasingly, disinfectants are included in consumer products. Broad-scale use of antiseptics and disinfectants may have detrimental ecological consequences, for instance the development of antimicrobial resistance. MATERIAL AND METHODS: We give an overview of the correlation between the use of certain antiseptics and disinfectants, bacterial resistance to these agents, and antibiotic resistance. RESULTS: The mechanisms of antibiotic and biocide resistance share many common characteristics. There are links between disinfectant resistance and antibiotic resistance. Some biocides have the ability to select for antibiotic resistant mutants and vice versa. Resistance genes are often located on transferable genetic elements that facilitate horizontal gene transfer between microorganisms. Antibiotic resistance and disinfectant resistance may be stabilized and maintained even in the absence of a direct selective pressure. Higher incidence of bacteria resistant to certain disinfectants have been reported in environments where such agents are frequently used compared to environments where they are not in regular use. Increased domestic usage of non-antibiotic antimicrobial agents may select for antibiotic-resistant bacteria of clinical significance. INTERPRETATION: The use of antiseptics and disinfectants should be restricted to products and areas where they have an essential and documented effect.


Asunto(s)
Antiinfecciosos Locales/efectos adversos , Desinfectantes/efectos adversos , Farmacorresistencia Bacteriana , Animales , Antiinfecciosos Locales/metabolismo , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Desinfectantes/metabolismo , Farmacorresistencia Bacteriana/genética , Humanos , Pseudomonas fluorescens/efectos de los fármacos , Pseudomonas fluorescens/metabolismo , Pseudomonas fluorescens/ultraestructura , Triclosán/efectos adversos
14.
Microb Drug Resist ; 7(4): 363-71, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11822776

RESUMEN

Little is known about the occurrence of antimicrobial resistance determinants in staphylococci isolated from food and food processing industries. Quaternary ammonium compound (QAC)-resistant coagulase-negative staphylococci (CNS) isolated from food and food-processing industries were investigated for the presence of genetic determinants (qacA/B and qacC/smr) encoding resistance to the QAC benzalkonium chloride (BC), several antibiotic resistance genes, and staphylococcal insertion sequences IS257 and IS256. Six qacA/B-harboring strains were resistant to penicillin and hybridized to a blaZ probe. The qacA/B and blaZ probes hybridized to plasmids of similar size in three isolates. Molecular and genetic characterization of the 23-kb plasmid (pST6) of Staphylococcus epidermidis St.6 revealed the presence of qacB adjacent to an incomplete beta-lactamase transposon Tn552 encoding the gene cluster blaZ, blaR, and blaI. Sequence analysis of flanking regions and the intergenic region between blaZ and qacB revealed the presence of IS257 downstream of blaZ as well as sin and binR between blaZ and qacB. In the three other BC and penicillin-resistant strains, the qacA/B and blaZ genes were located on separate plasmids. A qacC harboring S. epidermidis strain (St.17) also hybridized to tetK (tetracycline resistance) and ermB (erythromycin resistance) genes. The individual genes were located on separate plasmids, suggesting no linkage between QAC and antibiotic resistance determinants. Plasmid-free Staphylococcus aureus RN4220 allowed uptake of the pST6 plasmid DNA, indicating that the resistance genes could potentially be transferred to pathogens under selective stress. In conclusion, presence of both resistance determinants could lead to co-selection during antimicrobial therapy or disinfection in hospitals or in food industries.


Asunto(s)
Antibacterianos/farmacología , Microbiología de Alimentos , Compuestos de Amonio Cuaternario/farmacología , Staphylococcus/efectos de los fármacos , Staphylococcus/crecimiento & desarrollo , Resistencia betalactámica/genética , Antiinfecciosos Locales/farmacología , Compuestos de Benzalconio/farmacología , Southern Blotting , Medios de Cultivo , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , Farmacorresistencia Microbiana , Hibridación Genética , Pruebas de Sensibilidad Microbiana , Plásmidos/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transformación Bacteriana/genética , beta-Lactamas
15.
J Virol ; 74(10): 4831-8, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10775622

RESUMEN

A complete DNA copy of the genome of a Jeryl Lynn strain of mumps virus (15,384 nucleotides) was assembled from cDNA fragments such that an exact antigenome RNA could be generated following transcription by T7 RNA polymerase and cleavage by hepatitis delta virus ribozyme. The plasmid containing the genome sequence, together with support plasmids which express mumps virus NP, P, and L proteins under control of the T7 RNA polymerase promoter, were transfected into A549 cells previously infected with recombinant vaccinia virus (MVA-T7) that expressed T7 RNA polymerase. Rescue of infectious virus from the genome cDNA was demonstrated by amplification of mumps virus from transfected-cell cultures and by subsequent consensus sequencing of reverse transcription-PCR products generated from infected-cell RNA to verify the presence of specific nucleotide tags introduced into the genome cDNA clone. The only coding change (position 8502, A to G) in the cDNA clone relative to the consensus sequence of the Jeryl Lynn plaque isolate from which it was derived, resulting in a lysine-to-arginine substitution at amino acid 22 of the L protein, did not prevent rescue of mumps virus, even though an amino acid alignment for the L proteins of paramyxoviruses indicates that lysine is highly conserved at that position. This system may provide the basis of a safe and effective virus vector for the in vivo expression of immunologically and biologically active proteins, peptides, and RNAs.


Asunto(s)
ADN Complementario/genética , ADN Complementario/metabolismo , Virus de la Parotiditis/genética , Paperas/virología , Animales , Secuencia de Bases , Línea Celular , Embrión de Pollo , Cloranfenicol O-Acetiltransferasa/genética , Cloranfenicol O-Acetiltransferasa/metabolismo , Genes Reporteros , Datos de Secuencia Molecular , Virus de la Parotiditis/crecimiento & desarrollo , Virus de la Parotiditis/metabolismo , Nucleoproteínas/genética , Fosfoproteínas/genética , Plásmidos , Replicón/genética , Transfección
17.
J Virol ; 73(5): 3560-6, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10196245

RESUMEN

Rescue of negative-stranded RNA viruses from full-length genomic cDNA clones is an essential technology for genetic analysis of this class of viruses. Using this technology in our studies of measles virus (MV), we found that the efficiency of the measles virus rescue procedure (F. Radecke et al., EMBO J. 14:5773-5784, 1995) could be improved by modifying the procedure in two ways. First, we found that coculture of transfected 293-3-46 cells with a monolayer of Vero cells increased the number of virus-producing cultures about 20-fold. Second, we determined that heat shock treatment increased the average number of transfected cultures that produced virus another two- to threefold. In addition, heat shock increased the number of plaques produced by positive cultures. The effect of heat shock on rescue led us to test the effect on transient expression from an MV minireplicon. Heat shock increased the level of reporter gene expression when either minireplicon DNA or RNA was used regardless of whether complementation was provided by cotransfection with expression plasmids or infection with MV helper virus. In addition, we found that MV minireplicon gene expression could be stimulated by cotransfection with an Hsp72 expression plasmid, indicating that hsp72 likely plays a role in the effect of heat shock.


Asunto(s)
ADN Viral , Regulación Viral de la Expresión Génica , Respuesta al Choque Térmico/fisiología , Virus del Sarampión/genética , Animales , Línea Celular Transformada , Chlorocebus aethiops , Genes Virales , Proteínas del Choque Térmico HSP72 , Células HeLa , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Humanos , Replicón , Células Vero
19.
J Virol ; 72(4): 2905-16, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9525611

RESUMEN

This paper provides evidence for a measles virus receptor other than CD46 on transformed marmoset and human B cells. We first showed that most tissues of marmosets are missing the SCR1 domain of CD46, which is essential for the binding of Edmonston measles virus, a laboratory strain that has been propagated in Vero monkey kidney cells. In spite of this deletion, the common marmoset was shown to be susceptible to infections by wild-type isolates of measles virus, although they did not support Edmonston measles virus production. As one would expect from these results, measles virus could not be propagated in owl monkey or marmoset kidney cell lines, but surprisingly, both a wild-type isolate (Montefiore 89) and the Edmonston laboratory strain of measles virus grew efficiently in B95-8 marmoset B cells. In addition, antibodies directed against CD46 had no effect on wild-type infections of marmoset B cells and only partially inhibited the replication of the Edmonston laboratory strain in the same cells. A direct binding assay with insect cells expressing the hemagglutinin (H) proteins of either the Edmonston or Montefiore 89 measles virus strains was used to probe the receptors on these B cells. Insect cells expressing Edmonston H but not the wild-type H bound to rodent cells with CD46 on their surface. On the other hand, both the Montefiore 89 H and Edmonston H proteins adhered to marmoset and human B cells. Most wild-type H proteins have asparagine residues at position 481 and can be converted to a CD46-binding phenotype by replacement of the residue with tyrosine. Similarly, the Edmonston H protein did not bind CD46 when its Tyr481 was converted to asparagine. However, this mutation did not affect the ability of Edmonston H to bind marmoset and human B cells. The preceding results provide evidence, through the use of a direct binding assay, that a second receptor for measles virus is present on primate B cells.


Asunto(s)
Antígenos CD/metabolismo , Linfocitos B/metabolismo , Hemaglutininas Virales/metabolismo , Virus del Sarampión/metabolismo , Glicoproteínas de Membrana/metabolismo , Secuencia de Aminoácidos , Animales , Anticuerpos/inmunología , Antígenos CD/genética , Aotidae , Linfocitos B/citología , Secuencia de Bases , Callithrix , Línea Celular , Chlorocebus aethiops , ADN Complementario , Células HeLa , Humanos , Riñón/citología , Pulmón/citología , Proteína Cofactora de Membrana , Glicoproteínas de Membrana/genética , Datos de Secuencia Molecular , Saimiri , Eliminación de Secuencia , Células Vero
20.
Proc Natl Acad Sci U S A ; 94(25): 13961-6, 1997 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-9391135

RESUMEN

A live, cold-passaged (cp) candidate vaccine virus, designated respiratory syncytial virus (RSV) B1 cp-52/2B5 (cp-52), replicated efficiently in Vero cells, but was found to be overattenuated for RSV-seronegative infants and children. Sequence analysis of reverse-transcription-PCR-amplified fragments of this mutant revealed a large deletion spanning most of the coding sequences for the small hydrophobic (SH) and attachment (G) proteins. Northern blot analysis of cp-52 detected multiple unique read-through mRNAs containing SH and G sequences, consistent with a deletion mutation spanning the SH:G gene junction. Immunological studies confirmed that an intact G glycoprotein was not produced by the cp-52 virus. Nonetheless, cp-52 was infectious and replicated to high titer in tissue culture despite the absence of the viral surface SH and G glycoproteins. Thus, our characterization of this negative-strand RNA virus identified a novel replication-competent deletion mutant lacking two of its three surface glycoproteins. The requirement of SH and G for efficient replication in vivo suggests that selective deletion of one or both of these RSV genes may provide an alternative or additive strategy for developing an optimally attenuated vaccine candidate.


Asunto(s)
Proteína HN , Mutación , Virus Sincitial Respiratorio Humano/genética , Virus Sincitial Respiratorio Humano/fisiología , Proteínas Virales/genética , Proteínas Virales/fisiología , Animales , Niño , Chlorocebus aethiops , Mapeo Cromosómico , Eliminación de Gen , Genes Virales , Humanos , Lactante , Infecciones por Virus Sincitial Respiratorio/prevención & control , Virus Sincitial Respiratorio Humano/patogenicidad , Vacunas Atenuadas/genética , Vacunas Sintéticas/genética , Células Vero , Proteínas del Envoltorio Viral , Proteínas Virales/inmunología , Vacunas Virales/genética , Virulencia/genética , Replicación Viral/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA