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1.
Radiography (Lond) ; 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39214787

RESUMO

BACKGROUND: Ventricular tachycardia is an irregular heartbeat conventionally treated using invasive cardiac catheter ablation and medication. However, when standard treatments have been exhausted, cardiac SABR provides a final treatment option to this high-mortality condition. Complex diagnostic mapping and planning scans enable multi-disciplinary target delineation for a 25Gy single fraction. However, organs at risk (OAR) near the target make this treatment challenging to plan and deliver. Publications from cardiologists report the efficacy of cardiac SABR, however there is limited data on the treatment delivery and image matching of this complex procedure. METHODS: Four specialist therapeutic radiographers experienced in cardiac SABR reviewed 40 CBCTs from 10 patients treated in the UK. Each therapeutic radiographer conducted five image matches: a manual match (manual), an automatic match to the heart structure (auto) and the auto match followed by manual adjustment to the PTV (PTV), all using three degrees of freedom (DoF) only. The auto and PTV matches were also repeated using 6DoF. Inter-observer variability was quantified using 95% limits of agreement from a modified Bland-Altman analysis. RESULTS: The limits of agreement were smallest in the automatic matches suggesting the algorithm is reliable. A manual adjustment from the auto match to the PTV is clinically appropriate to optimise target coverage. The limits of agreement were smaller in the 6DoF PTV match 1.06 mm, 1.24 mm, 1.68 mm than the 3DoF PTV match 1.57 mm, 2.06 mm, 2.11 mm (lateral, vertical, longitudinal). CONCLUSION: The 6DoF CBCT image match has less variability and therefore suggest using a 6DoF couch for treatment delivery. IMPLICATIONS FOR PRACTICE: Cardiac SABR CBCT image matching at treatment delivery is complex, optimisation of CBCT acquisition parameters and therapeutic radiographer training is essential prior to implementation.

2.
Occup Med (Lond) ; 73(5): 263-267, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37253148

RESUMO

BACKGROUND: Job exposure matrices (JEMs) are epidemiological tools used to provide estimations of occupational exposures when it is not feasible to complete detailed individual occupational histories. AIMS: To identify and summarize the characteristics of published general population JEMs (GPJEM) of inhalable occupational exposures applied in studies of respiratory disease. METHODS: MEDLINE and EMBASE databases were searched using pre-defined search terms, with screening performed by two independent reviewers to identify studies reporting the use of a GPJEM. JEM creation papers were subsequently identified and reviewed for each individual GPJEM, noting its characteristics in terms of occupational classification system and exposure estimates. RESULTS: From 728 studies identified in initial searches, 33 GPJEMs of inhalable occupational exposures were identified. Versions of the International Standards Classification of Occupations were the most used occupational classification system. Binary, probability and intensity-based exposure estimates were most frequently reported in GPJEMs. CONCLUSIONS: Selection of a GPJEM to apply in epidemiological research should be based on the exposure(s) of interest, time period of occupations under review, geographical region for intended use, occupation classification system used and the exposure estimate outcome.


Assuntos
Doenças Profissionais , Exposição Ocupacional , Humanos , Ocupações , Exposição Ocupacional/efeitos adversos , Doenças Profissionais/epidemiologia
3.
Occup Med (Lond) ; 72(8): 541-549, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36097688

RESUMO

BACKGROUND: Work-related asthma symptoms are common in teachers and teaching assistants, there are few studies evaluating their causes. AIMS: To identify causes of occupational asthma in teachers and teaching assistants referred to the Birmingham Occupational Lung Disease clinic 2000-20 using evaluation of serial Peak Expiratory Flow (PEF) records. METHODS: Teachers and teaching assistants with possible occupational asthma were asked to record PEF 2-hourly at home and work for 4 weeks. Their records were evaluated with the Oasys programme. Those with a positive score for any of the three scores (area between curves (ABC), timepoint and Oasys score from discriminant analysis) were included. Repeat records were made as indicated to help identify the cause and the effects of remedial actions. RESULTS: Thirty-eight teachers or teaching assistants met the inclusion criteria with all three Oasys scores positive in 24, 2/3 scores in nine and 1/3 in five. The building was the likely cause in 17 (in new builds particularly acrylates from carpet adhesives and in old buildings mould and construction dust), bystander exposure to agents in the schools in 12 (cleaning agents, acrylates from photocopiers and chloramines from indoor pools) and materials used in the classroom in 9 (most commonly MDF in design and technology classes). We illustrate how the PEF records helped identify the cause. CONCLUSIONS: Oasys analysis of PEF records is a useful method of evaluating occupational asthma in teachers and identified difficult to confirm causes where successful remediation or redeployment was achieved.


Assuntos
Asma , Doenças Profissionais , Professores Escolares , Humanos , Instituições Acadêmicas
4.
Occup Med (Lond) ; 72(6): 411-414, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35460246

RESUMO

BACKGROUND: Office work has a relative perception of safety for the worker. Data from surveillance schemes and population-based epidemiological studies suggest that office work carries a low risk of occupational asthma (OA). Office workers are frequently used as comparators in studies of occupational exposure and respiratory disease. AIMS: We aimed to describe and illustrate our tertiary clinical experience of diagnosing OA in office workers. METHODS: We searched the Birmingham NHS Occupational Lung Disease Service clinical database for cases of occupational respiratory disease diagnosed between 2002 and 2020, caused by office work or in office workers. For patients with OA, we gathered existing data on demographics, diagnostic tests including Occupational Asthma SYStem (OASYS) analysis of serial peak expiratory flow and specific inhalational challenge, and employment outcome. We summarised data and displayed them alongside illustrative cases. RESULTS: There were 47 cases of OA (5% of all asthma) confirmed using OASYS analysis of PEFs in the majority. Sixty percent of cases occurred in healthcare, education and government sectors. The most frequently implicated causative exposures or agents were: indoor air (9), printing, copying and laminating (7), cleaning chemicals (4), mould and damp (4), and acrylic flooring and adhesives (4). Exposures were grouped into internal office environment, office ventilation-related and adjacent environment. CONCLUSIONS: Clinicians should be vigilant for exposures associated with OA in office workers who present with work-related symptoms, where respiratory sensitizing agents may be present. A structured approach to assessment of the workplace is recommended.


Assuntos
Asma Ocupacional , Doenças Profissionais , Exposição Ocupacional , Asma Ocupacional/diagnóstico , Asma Ocupacional/epidemiologia , Asma Ocupacional/etiologia , Humanos , Doenças Profissionais/diagnóstico , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Pico do Fluxo Expiratório , Testes de Função Respiratória
5.
Clin Oncol (R Coll Radiol) ; 33(5): 283-291, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33341333

RESUMO

AIMS: To report long-term outcomes of patients treated with stereotactic ablative radiotherapy (SABR) for early stage, peripherally located non-small cell lung cancer. MATERIALS AND METHODS: Data were collected retrospectively between September 2009 and May 2019. Electronic medical records were reviewed for baseline characteristics, treatment details and outcomes. All patients were treated according to local protocol based on the national UK SABR Consortium guidelines. Risk-adapted treatment schedules were used depending on the size and the location of the tumour (54 Gy in three fractions, 55 Gy in five fractions, 60 Gy in eight fractions or 50 Gy in 10 fractions). Overall survival outcomes were evaluated using the Kaplan-Meier method. RESULTS: In total, 412 patients were included in the analysis. The median age was 76 years (range 48-93 years). Histological confirmation was obtained in 233 cases (56.6%). The median overall survival for all patients was 42.3 months (95% confidence interval 37.3-47.3 months), with 3- and 5-year overall survival of 52.8% and 37.3%, respectively. For biopsy-proven patients (56.6%), 3- and 5-year overall survival was 57.3% and 40.1%, respectively. With respect to overall survival, univariate and multivariate analysis revealed no significant difference in survival by technique (volume-modulated arc therapy versus conformal; three-dimensional computed tomography versus four-dimensional computed tomography), tumour location, smoking status at first contact, pre-treatment tumour stage or pre-treatment standardised uptake value. Survival was poorer for patients who received the 50 Gy in 10 fractions schedule. Treatment was very well tolerated with very low rates of grade 3-4 toxicity (1%). CONCLUSIONS: SABR for peripherally located, medically inoperable non-small cell lung cancer can be safely and effectively implemented in a non-academic institution with appropriate equipment and training. Overall survival outcomes and toxicity rates are comparable with internationally published studies. Patients treated with 50 Gy in 10 fractions had a poorer survival outcome.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/mortalidade , Radiocirurgia/mortalidade , Idoso , Idoso de 80 Anos ou mais , Institutos de Câncer , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Tomografia Computadorizada Quadridimensional , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radiocirurgia/métodos , Estudos Retrospectivos , Taxa de Sobrevida
6.
Occup Med (Lond) ; 70(7): 490-495, 2020 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-33063819

RESUMO

BACKGROUND: A previous systematic review of the diagnosis of reactive airways dysfunction syndrome (RADS), undertaken from 1985 to 2004, found a lack of standardization of case reporting, thus misattribution of symptoms can occur. AIMS: We aimed to update the systematic review, update the list of reported causes and see whether a more structured approach to reporting has been adopted. METHODS: We undertook a systematic literature review, using the databases EMBASE and Ovid MEDLINE, with search terms 'reactive airways dysfunction syndrome' or 'asthma AND acute irritant', and reported according to PRISMA guidelines. We included papers and abstracts published from January 2005 to September 2019, and articles were grouped by the presence or absence of diagnostic features: 'definite' RADS (met Brooks' criteria) or 'possible' RADS (Brooks' criteria not met or insufficient data). We collected demographic and diagnostic data for cases, where given. RESULTS: Eleven papers and six conference abstracts met the inclusion criteria, 13 of which were case series or reports, and comprised 752 cases in total; seven articles met Brooks' criteria for RADS diagnosis. A variety of agents were implicated, with chlorine or chlorine-releasing molecules most frequently reported. CONCLUSIONS: A lack of standardized reporting of RADS remains. The majority of published articles and conference abstracts either do not meet, or contain insufficient data to judge against, Brooks' criteria, particularly in relation to onset of symptoms and bronchial hyper-reactivity or variability of airflow obstruction. Some novel agents are described, in keeping with recognized structural taxonomies.


Assuntos
Asma/induzido quimicamente , Doenças Profissionais/induzido quimicamente , Hipersensibilidade Respiratória/induzido quimicamente , Poluentes Atmosféricos/efeitos adversos , Asma/diagnóstico , Exposição Ambiental/efeitos adversos , Humanos , Irritantes/efeitos adversos , Doenças Profissionais/diagnóstico , Exposição Ocupacional/efeitos adversos , Hipersensibilidade Respiratória/diagnóstico
7.
J Med Primatol ; 32(2): 82-8, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12823630

RESUMO

Human respiratory syncytial virus (RSV) is a major cause of acute upper and lower respiratory tract infections. RFI-641 is a novel RSV fusion inhibitor with potent in vitro activity. In vivo efficacy of RFI was determined in an African green monkey model of RSV infection involving prophylactic and therapeutic administration by inhalation exposure. Inhalation was with an RFI-641 nebulizer reservoir concentration of 15 mg/ml for 15 minutes (short exposure) or 2 hours (long exposure). Efficacy and RFI-641 exposure was determined by collection of throat swabs, nasal washes and bronchial alveolar lavage (BAL) on selected days. The short-exposure group (15 minutes) exhibited no effect on the nasal, throat or BAL samples. The throat and nasal samples for the long-exposure group failed to show a consistent reduction in viral titers. RFI-641 2 hours exposure-treated monkeys showed a statistically significantly log reduction for BAL samples of 0.73-1.34 PFU/ml (P-value 0.003) over all the sampling days. Analysis indicates that the long-exposure group titer was lower than the control titer on day 7 and when averaged across days. The results of this study demonstrate the ability of RFI-641 to reduce the viral load of RSV after inhalation exposure in the primate model of respiratory infection.


Assuntos
Chlorocebus aethiops/virologia , Modelos Animais de Doenças , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Sulfonamidas/administração & dosagem , Sulfonamidas/uso terapêutico , Triazinas/administração & dosagem , Triazinas/uso terapêutico , Administração por Inalação , Aerossóis/administração & dosagem , Aerossóis/química , Aerossóis/uso terapêutico , Animais , Líquido da Lavagem Broncoalveolar/virologia , Feminino , Masculino , Estrutura Molecular , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Vírus Sinciciais Respiratórios/fisiologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Triazinas/química , Triazinas/farmacologia
8.
Artigo em Inglês | MEDLINE | ID: mdl-11563103

RESUMO

The synthesis of 1-(beta-D-ribofuranosyl)pyridin-2-one-3-carboxylic acid and the 3-carboxamide as well as a short series of 3N-carboxamides, prepared by TPTU/HOBt coupling of primary amines with 1-(beta-D-ribofuranosyl)pyridin-2-one-3-carboxylic acid, and their evaluation as anti-infective agents is described.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Piridinas/síntese química , Piridinas/farmacologia , Ribonucleosídeos/síntese química , Ribonucleosídeos/farmacologia , Amidas/síntese química , Amidas/farmacologia , Ácidos Carboxílicos/síntese química , Ácidos Carboxílicos/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos
9.
Org Lett ; 2(20): 3143-4, 2000 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11009366

RESUMO

The structure of the active glyoxalase I inhibitor derived from the Streptomyces griseosporeus metabolite COTC 1 has been conclusively identified by means of total synthesis as 2c. Human glyoxalase I is competitively inhibited by 2c (K(i)() = 183 +/- 6 microM) but is not inhibited by 1 itself.


Assuntos
Antibióticos Antineoplásicos/química , Cicloexanonas/química , Inibidores Enzimáticos/síntese química , Glutationa/química , Lactoilglutationa Liase/antagonistas & inibidores , Inibidores Enzimáticos/química , Humanos , Streptomyces/química
10.
J Virol ; 74(13): 5886-95, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10846069

RESUMO

The phosphoproteins (P proteins) of paramyxoviruses play a central role in transcription and replication of the viruses by forming the RNA polymerase complex L-P and encapsidation complex (N-P) with nucleocapsid protein (N) and binding to N protein-encapsidated genome RNA template (N-RNA template). We have analyzed the human parainfluenza virus type 3 (HPIV3) P protein and deletion mutants thereof in an in vitro transcription and in vivo replication system. The in vitro system utilizes purified N-RNA template and cell extract containing L and P proteins coexpressed via plasmids using a recombinant vaccinia virus expression system. The in vivo system takes advantage of minigenome replication, which measures luciferase reporter gene expression from HPIV3 minigenomes by viral proteins in a recombinant vaccinia virus expression system. These studies revealed that the C-terminal 20-amino-acid region of P is absolutely required for transcription in vitro and luciferase expression in vivo, suggesting its critical role in viral RNA synthesis. The N-terminal 40-amino-acid region, on the other hand, is essential for luciferase expression but dispensable for transcription in vitro. Consistent with these findings, the C-terminal domain is required for binding of P protein to the N-RNA template involved in both transcription and replication, whereas the N-terminal domain is required for the formation of soluble N-P complex involved in encapsidation of nascent RNA chains during replication. Coimmunoprecipitation analysis showed that the P protein forms a stable homooligomer (perhaps a trimer) that is present in L-P and N-P complexes in the higher oligomeric forms (at least a pentamer). Interestingly, coexpression of a large excess of N- or C-terminally deleted P with wild-type P had no effect on minigenome replication in vivo, notwithstanding the formation of heterooligomeric complexes. These data indicate that P protein with a deleted terminal domain can function normally within the P heterooligomeric complex to carry out transcription and replication in vivo.


Assuntos
Regulação Viral da Expressão Gênica , Vírus da Parainfluenza 3 Humana/genética , Fosfoproteínas/fisiologia , Transcrição Gênica , Proteínas Virais/fisiologia , Replicação Viral , Linhagem Celular , Genoma Viral , Células HeLa , Humanos , Mutagênese , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Estrutura Terciária de Proteína , RNA Mensageiro , RNA Viral , Moldes Genéticos , Proteínas Virais/genética , Proteínas Virais/metabolismo
11.
Am J Health Syst Pharm ; 55(2): 137-44, 1998 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9465977

RESUMO

Guidelines for describing cancer chemotherapy regimens in all aspects of drug development, including treatment protocols, order forms, and product labels, are proposed. To complement the approaches to reducing medication errors that have been recommended by ASHP and others, pharmacists at the National Institutes of Health and the National Cancer Institute, with the input of oncology pharmacists from diverse areas of practice, developed guidelines for expressing chemotherapy dosage schedules and treatment regimens. The guidelines present standards that are broadly applicable and can be adopted by other institutions. Clear and unambiguous expression of all medication orders and consistency of treatment descriptions are suggested. Written treatment plans and orders should contain enough information to allow health care providers from diverse disciplines to compare them with published treatment descriptions and investigational protocols and must therefore include planned dosages and schedules expressed in patient-specific units. In general, drug dosages should be expressed as the amount of drug administered from a single container. When ordering drugs that are part of complex or combination-drug regimens, prescribers should write as many of the orders at one time as is possible, so that continuity might be preserved. Standard rules are proposed for describing chemotherapy regimens.


Assuntos
Antineoplásicos/administração & dosagem , Esquema de Medicação , Rotulagem de Medicamentos/normas , Guias de Prática Clínica como Assunto , Terminologia como Assunto , American Medical Association , American Nurses' Association , Educação em Farmácia/normas , Controle de Formulários e Registros/normas , Humanos , Erros de Medicação , National Institutes of Health (U.S.) , Sociedades Farmacêuticas , Estados Unidos
12.
J Biol Chem ; 272(26): 16578-84, 1997 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-9195969

RESUMO

The phosphoproteins (P) of nonsegmented negative strand RNA viruses are viral RNA polymerase subunits involved in both transcription and replication during the virus life cycle. Phosphorylation of P proteins in several negative strand RNA viruses by specific cellular kinases was found to be required for P protein function. In the present study, using bacterially expressed unphosphorylated P protein of Sendai virus, a mouse parainfluenza virus, we have shown that the major cellular kinase that phosphorylates P protein in vitro is biochemically and immunologically indistinguishable from protein kinase C (PKC) zeta isoform. PKC zeta was packaged into the Sendai virion and remained associated with purified viral ribonucleoprotein, where it phosphorylated both the P and the nucleocapsid protein in vitro. When PKC zeta-specific inhibitory pseudosubstrate peptide was introduced into LLC-MK2 cells prior to Sendai virus infection, production of progeny virus was dramatically attenuated, and kinetic analysis revealed that primary transcription was repressed. These data indicate that phosphorylation of the Sendai virus P protein by PKC zeta plays a critical role in the virus life cycle.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Isoenzimas/fisiologia , Fosfoproteínas/metabolismo , Proteína Quinase C/fisiologia , Proteínas Virais/metabolismo , Animais , Camundongos , Fosforilação , Proteínas Recombinantes/metabolismo , Respirovirus/fisiologia , Ribonucleoproteínas/análise , Replicação Viral
13.
Virology ; 232(1): 198-206, 1997 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-9185603

RESUMO

Transcription by nonsegmented negative-strand RNA viruses is mediated by the viral RNA-dependent RNA polymerase and transcriptional cofactor P. The P protein is activated by phosphorylation, an event initiated by cellular kinases. The kinase used differs among this group of RNA viruses; vesicular stomatitis virus and respiratory syncytial virus utilize casein kinase II (CKII), whereas human parainfluenza virus type 3 utilizes PKC isoform zeta (PKC-zeta) for activation of its P protein. To identify the cellular kinase(s) involved in the phosphorylation of the canine distemper virus (CDV) P protein, we used recombinant CDV P in phosphorylation assays with native kinase activities present in CV1 cell extracts or purified CKII and PKC isoforms. Here, we demonstrate that the CDV P protein is phosphorylated by two cellular kinases, where PKC-zeta has the major and CKII the minor activities. In contrast, the P protein of another member of the morbillivirus genus, measles virus, is phosphorylated predominantly by CKII, whereas PKC-zeta has only minor activity. Selective inhibition of PKC-zeta activity within CV1 cells eliminated permissiveness to CDV replication, indicating an in vivo role for PKC-zeta in the virus replication cycle. The broad tissue expression of PKC-zeta parallels the pantropic nature of CDV infections, suggesting that PKC-zeta activity is a determinant of cellular permissiveness to CDV replication.


Assuntos
Vírus da Cinomose Canina/metabolismo , Proteína Quinase C/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Virais/metabolismo , Animais , Caseína Quinase II , Chlorocebus aethiops , Clonagem Molecular , Vírus da Cinomose Canina/fisiologia , Inibidores Enzimáticos/farmacologia , Escherichia coli/genética , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Células Vero , Replicação Viral/efeitos dos fármacos
14.
Virology ; 211(2): 561-7, 1995 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-7645259

RESUMO

The human parainfluenza virus type 3 P protein is an RNA polymerase subunit involved in both transcription and replication during the life cycle of the virus. Our laboratory has recently shown that the P protein is phosphorylated both in vitro and in vivo by the cellular protein kinase C (PKC) isoform zeta and that this phosphorylation is essential for viral replication. To identify the site(s) of phosphorylation, we have used CNBr cleavage, phosphoamino acid analysis, and two-dimensional tryptic peptide mapping of the in vitro and in vivo phosphorylated P protein. We demonstrate that when bacterially expressed unphosphorylated P is labeled in vitro with either commercial PKC or purified recombinant PKC zeta P protein has one major phosphorylation site. By site-directed mutagenesis of PKC consensus sites in the P protein, the primary phosphorylation site is found to be Ser 333. The same site appeared to be modified when viral P protein was phosphorylated in vitro by the PKC packaged within the virion and in the P protein of progeny virion labeled in vivo.


Assuntos
Vírus da Parainfluenza 3 Humana/metabolismo , Fosfoproteínas/metabolismo , Proteína Quinase C/metabolismo , Serina/metabolismo , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Humanos , Dados de Sequência Molecular , Fosfoproteínas/genética , Fosforilação , Especificidade por Substrato , Proteínas Virais/genética
15.
Arch Virol Suppl ; 9: 181-94, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8032249

RESUMO

Studies using brome mosaic virus (BMV), Sindbis virus and poliovirus have provided evidence that disparate groups of plant and animal positive strand RNA viruses have remarkably similar replication strategies. The conservation of several functional domains within virus-encoded nonstructural proteins implies that, although the precise character of these and interacting host components varies for each virus, they employ similar mechanisms for RNA replication. For (+) strand replication, similarities in cis-acting sequence motifs and RNA secondary structures within 5' termini of genomic (+) strands have been identified and have been shown to participate in binding of host factors. The model presented for replication of BMV RNA suggests that binding of these factors to internal control region (ICR) sequence motifs in the double-stranded replication intermediate releases a single-stranded 3' terminus on the (-) strand that may be essential for initiation of genomic (+) strand synthesis. ICR sequences internal to the BMV genome were also found to be required for efficient replication. Asymmetric production of excess genomic (+) over (-) strand RNA, characteristic of all (+) strand viruses, may be accomplished through transition of the replicase from competence for (-) to (+) strand synthesis by the recruitment of additional host factors.


Assuntos
Modelos Genéticos , Vírus de RNA/crescimento & desenvolvimento , RNA Viral/biossíntese , Bromovirus/genética , Bromovirus/crescimento & desenvolvimento , Análise Mutacional de DNA , Conformação de Ácido Nucleico , Poliovirus/genética , Poliovirus/crescimento & desenvolvimento , Vírus de RNA/genética , Sindbis virus/genética , Sindbis virus/crescimento & desenvolvimento , Replicação Viral
16.
J Gen Virol ; 74 ( Pt 11): 2445-52, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8245860

RESUMO

Sense and antisense strategies for interfering with the replication of brome mosaic virus (BMV) were examined. The effects of 200 nucleotide-long sense and antisense transcripts, corresponding to the viral 3' end (-) strand promoter, on the accumulation of progeny viral RNAs were studied by co-inoculation with wildtype BMV RNAs. Progeny accumulation in barley protoplasts transfected with either sense or antisense transcripts of the (-) strand promoter and BMV RNAs-1 and -2 was decreased by more than 90%, and by 60 to 80% when RNA-3 was also present. This trans interference was concentration-dependent, and reduced both (+) and (-) strand progeny accumulation to a similar extent. The appearance of complementary (-) strands indicated that sense interfering transcripts could serve as templates for (-) strand synthesis, and the use of deletion mutants revealed that the observed interference was in part mediated by this template activity. The reproducibility of the protoplast assay used here allows rapid evaluation of interference strategies and comparisons to be made of alternative approaches to engineered resistance. The results presented here suggest that targeting viral (-) strand promoters with sense and antisense transcripts may be an effective method for engineering plant resistance to viral infection.


Assuntos
Bromovirus/fisiologia , Regiões Promotoras Genéticas/fisiologia , RNA Viral/fisiologia , Replicação Viral/genética , Sequência de Bases , Bromovirus/genética , Deleção de Genes , Hordeum/microbiologia , Dados de Sequência Molecular , Protoplastos/microbiologia , RNA Antissenso , RNA Mensageiro/fisiologia , RNA Viral/genética
17.
Ment Retard ; 31(4): 215-20, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8412726

RESUMO

Techniques were identified that staff of agencies serving adults or adolescents with mental retardation perceived would enable them to provide systematic sex education and counseling. Through the use of a structured interview process, we obtained opinions of professionals from 16 agencies. On the basis of these interviews and a thorough review of related literature, we made recommendations aimed at increasing professionals' ability to provide systematic sex education and counseling for individuals with mental retardation. Suggestions for further study were presented.


Assuntos
Educação de Pessoa com Deficiência Intelectual/métodos , Deficiência Intelectual/reabilitação , Educação Sexual/métodos , Adolescente , Adulto , Currículo , Desinstitucionalização , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Equipe de Assistência ao Paciente
18.
Virology ; 192(1): 290-7, 1993 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8517022

RESUMO

Interference with virus replication through the use of defective viral sequences is providing new insight to replication strategies and novel approaches for induced resistance. Because replication of brome mosaic virus (BMV) is potentiated by the intercistronic region of RNA-3, we examined the effect of adding various (-)sense RNAs corresponding to this region in co-transfections with wild type BMV RNAs. Progeny accumulation in barley protoplasts transfected with RNAs 1+2 was decreased by 90% in the presence of (-)RNA-3 delta HindIII, the longest (-)sense transcript tested, and by 85% when RNA-3 was also present. This trans interference was concentration dependent, and the use of deletion derivatives of (-)RNA-3 delta HindIII revealed that previously identified regulatory sequences within the intercistronic region were responsible for the observed interference. These deletion mutants were found to be of differing stabilities and several served as effective substrates for host-encoded polymerase to yield complementary (+)strands. Indeed, it is possible that the copying of viral RNA by the host polymerase serves as a hybrid arrest mechanism for discriminating against viral RNA functions. However, neither the ability of these sequences to serve as templates for host polymerase nor their (+)strand products contributed to the interference phenomenon, which may provide a new approach for engineering resistance to viral infection.


Assuntos
Regulação Viral da Expressão Gênica , Vírus do Mosaico/genética , RNA Viral/genética , Replicação Viral , Capsídeo/metabolismo , Células Cultivadas , Hordeum , RNA Polimerase Dependente de RNA/metabolismo , Deleção de Sequência
19.
Virology ; 182(1): 76-83, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-2024481

RESUMO

Transfection of barley protoplasts with brome mosaic virus (BMV) RNAs 1 + 2 in the absence of RNA-3 yielded a molar ratio for (+):(-)-strand progeny at 24 hr postinoculation near unity, whereas over 100-fold more (+)- than (-)-strand progeny accumulated in its presence. The presence of RNA-3 enhanced total (+)-strand RNA production 205-fold and that of RNAs 1 + 2 by 29-fold. In contrast, total (-)-strand RNA accumulation decreased by 68% and that for (-)RNAs 1 + 2 by 79% in the presence of RNA-3. Transfections containing an RNA-3 mutant (Gsgi----U RNA-3) that is incapable of yielding RNA-4 as a result of a single nucleotide substitution at the subgenomic RNA initiation site yielded only 66% of the (+):(-) asymmetry seen in the presence of wild-type RNA-3. Only 1.8-fold excess of (+)-over (-)-strand production was obtained for transfections that included delta SGP RNA-3, a deletion that includes the subgenomic promoter core and extends 43 nt into the RNA-4 sequence. Transfections containing RNA-3 mutants bearing frameshifts or deletions in the coat protein cistron yielded levels of asymmetry similar to those seen for Gsgi----U RNA-3. These findings implicate the subgenomic promoter and other sequences in the intercistronic region of RNA-3 as the primary determinants of asymmetric replication, although the coat protein may be an additional factor enhancing the accumulation of (+)-strand RNA.


Assuntos
Vírus do Mosaico/genética , RNA Viral/genética , Replicação Viral , Capsídeo/genética , Clonagem Molecular , Análise Mutacional de DNA , Hordeum/microbiologia , Plasmídeos , Regiões Promotoras Genéticas , Mapeamento por Restrição , Transcrição Gênica
20.
J Virol Methods ; 30(3): 239-50, 1990 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1707891

RESUMO

Non-radioactive biotinylated RNA probes specific for plus (+) and minus (-) sense RNAs of brome mosaic virus (BMV) were synthesized in vitro from a plasmid bearing a 200 base pair fragment complementary to the 3' terminus of each of the three genomic RNAs of the virus. Using virion RNAs isolated from BMV infected barley plants, the sensitivity of biotinylated RNAs as hybridization probes was compared with that of 32P-labeled probes in Northern hybridization assays. Although the sensitivity of biotinylated and 32P-labeled probes is similar (approximately 5 pg), the time required to detect the RNA bands was much less than for autoradiography; (-) sense RNAs could be detected in 30 min whereas 48 h or more were required by autoradiography. The value of biotinylated probes for following RNA stability was exemplified by the detection of supplied inocula in protoplasts 24 h post-inoculation. Quantitation of relative accumulation of progeny (+) and (-) sense RNAs by densitometry of the Northern blots probed with biotinylated RNAs paralleled that of radiolabeled probes. The application of these probes was extended to the detection of RNAs in barley protoplasts and BMV infected plant sap by dot hybridization. In these tests, viral RNAs were detected in as few as 250 protoplasts and sap dilutions up to 1:2000. The merits of these non-radioactive probes in monitoring the replication events by the detection and quantitation of mutant progeny RNAs of BMV are discussed.


Assuntos
Biotina , Vírus do Mosaico/genética , Sondas RNA , RNA Viral/análise , RNA/análise , Northern Blotting , DNA Viral/análise , Densitometria , Vírus do Mosaico/crescimento & desenvolvimento , Mutação , Plantas/microbiologia , Plasmídeos , Protoplastos/ultraestrutura , RNA Complementar , Sensibilidade e Especificidade , Replicação Viral/genética
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