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1.
Radiography (Lond) ; 28(2): 524-530, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34961676

RESUMO

INTRODUCTION: The evolution of technology within healthcare is continuing at a rapid rate. Touchless technologies (i.e. those involving gestures and voice commands) are rapidly being integrated into daily life. The aim of this study was to investigate the potential role for such technologies within diagnostic radiography. METHODS: An online survey was developed, piloted and deployed using SurveyMonkey as part of an online radiology congress. Eligible respondents were radiographers or radiologic technologists, including students. The survey covered ten themes relating to the potential role of touchless technologies within diagnostic radiography. Results were analysed using descriptive and inferential statistics. RESULTS: 155 people completed the questionnaire. 100 (64.9%) were women and clinical experience ranged from 13.5 (0-40) years. The majority, 54 (35.1%), had a Bachelor's degree with respondents being from 23 different countries (five continents). 34 (21.9%) respondents did not personally own nor intended to purchase touchless technologies. 89 (84.8%) respondents saw themselves using touchless technologies, if available on current imaging equipment. 25 (16.0%) respondents reported that they currently have access to touchless technologies within their workplace. 88 (81.5%) and 67 (65.0%) respondents reported that they saw voice and gesture controls as being key in improving exam efficiency. CONCLUSION: Participants clearly perceived a role for touchless technologies within diagnostic radiography. Access to such technologies is not yet widely available within X-ray rooms. Voice activated technologies appear more appealing that gesture-based aids. The primary role for such technologies was defined by participants as focusing on improving examination efficiency. IMPLICATIONS FOR PRACTICE: Touchless technologies have been identified and as important and potentially useful in diagnostic radiography. Collaboration between healthcare institutions, industry and academia is required to design and successfully implement these technologies into practice.


Assuntos
Gestos , Radiologia , Feminino , Humanos , Masculino , Radiografia , Inquéritos e Questionários , Tecnologia
2.
Radiography (Lond) ; 27(1): 193-199, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32855021

RESUMO

INTRODUCTION: Modifications to common radiographic techniques have resulted from the challenges presented by the COVID-19 pandemic. Reports exist regarding the potential benefits of undertaking mobile radiography through side room windows. The aim of this study was to evaluate the impact on image quality and exposure factors when undertaking such examinations. METHODS: A phantom based study was undertaken using a digital X-ray room. Control acquisitions, using a commercially available image quality test tool, were performed using standard mobile chest radiography acquisition factors. Image quality (physical and visual), incidence surface air kerma (ISAK), Exposure Index (EI) and Deviation Index (DI) were recorded. Image quality and radiation dose were further assessed for two additional (experimental) scenarios, where a side room window was located immediately adjacent to the exit port of the light beam diaphragm. The goal of experimental scenario one was to modify exposure factors to maintain the control ISAK. The goal of experimental scenario two was to modify exposure factors to maintain the control EI and DI. Dose and image quality data were compared between the three scenarios. RESULTS: To maintain the pre-window (control) ISAK (76 µGy), tube output needed a three-fold increase (90 kV/4 mAs versus 90 kV/11.25 mAs). To maintain EI/DI a more modest increase in tube output was required (90 kV/8 mAs/ISAK 54 µGy). Physical and visual assessments of spatial resolution and signal-to-noise ratio were indifferent between the three scenarios. There was a slight statistically significant reduction in contrast-to-noise ratio when imaging through the glass window (2.3 versus 1.4 and 1.2; P = 0.005). CONCLUSION: Undertaking mobile X-ray examinations through side room windows is potentially feasible but does require an increase in tube output and is likely to be limited by minor reductions in image quality. IMPLICATIONS FOR PRACTICE: Mobile examinations performed through side room windows should only be used in limited circumstances and future clinical evaluation of this technique is warranted.


Assuntos
COVID-19/diagnóstico por imagem , Radiografia Torácica/métodos , Serviço Hospitalar de Radiologia/organização & administração , Humanos , Imagens de Fantasmas , Doses de Radiação
3.
J Med Chem ; 39(3): 789-95, 1996 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-8576922

RESUMO

A series of 5-substituted 2'-deoxy-4'-thiopyrimidine nucleosides was synthesized and evaluated as potential antiviral agents. A number of analogues such as 2'-deoxy-5-propyl-4'-thiouridine (3ii), 2'-deoxy-5-isopropyl-4'-thiouridine (3iii), 5-cyclopropyl-2'-deoxy-4'-thiouridine (3iv), 2'-deoxy-4'-thio-5-vinyluridine (3viii), and 5-(2-chloroethyl)-2'-deoxy-4'-thiouridine (3xx) were found to be highly active against herpes simplex virus type-1 (HSV-1) and varicella zoster virus (VZV) in vitro with no significant cytotoxicity. The compound with the broadest spectrum of activity was 2'-deoxy-5-ethyl-4'-thiouridine (3i) which showed significant activity against HSV-1, HSV-2, and VZV.


Assuntos
Antivirais/síntese química , Antivirais/farmacologia , Nucleosídeos de Pirimidina/síntese química , Nucleosídeos de Pirimidina/farmacologia , Simplexvirus/efeitos dos fármacos , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Humanos , Células Vero , Ensaio de Placa Viral
4.
Chest ; 71(2): 234-6, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-832503

RESUMO

A bullet was found at necropsy in the left ventricle of a man who died of carcinoma of the urinary bladder. The bullet had entered the body at an unknown time in the remote past. The bullet probably gained entrance to the heart through the left atrial wall and lodged in the left ventricle.


Assuntos
Corpos Estranhos/etiologia , Ventrículos do Coração , Ferimentos por Arma de Fogo/complicações , Idoso , Ventrículos do Coração/patologia , Humanos , Pulmão/patologia , Masculino , Miocárdio/patologia
5.
Antivir Chem Chemother ; 12(3): 175-86, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-12959326

RESUMO

The efficacies of ganciclovir (GCV), penciclovir (PCV) and acyclovir (ACV) in inducing cell death in the herpes simplex virus thymidine kinase (HSVTK) system were compared. HSVTK-transformed baby hamster kidney cells treated with GCV, PCV or ACV were monitored for growth by viable count, and for death by TUNEL assay, propidium iodide staining, detection of phosphatidyl serine translocation and detection of DNA laddering. All compounds delayed growth or reduced viability of HSVTK-transformed cells. Drug treatment reduced levels of cyclin B1 message (which normally peaks in G2/M-phase of the cell cycle) and induced a four- to fivefold upregulation of GADD45 message. Treatment with GCV or PCV induced rapid accumulation of cells in S-phase and apoptotic death. Treatment with ACV, however, was associated with sustained S-phase arrest. GCV (and to a lesser extent PCV) increased phosphatidyl serine translocation, induced positive TUNEL results with alterations in cell morphology, caused marked propidium iodide staining and induced DNA laddering. By contrast, up to 7 days' exposure to ACV did not induce DNA laddering, with very little TUNEL staining. ACV treatment had little effect on phosphatidyl serine translocation and propidium iodide staining was markedly reduced compared with treatment with the other compounds. Thus, by all criteria, GCV was the most potent inducer of cell death. The current theories regarding apoptosis or necrosis as the preferred form of cell death in prodrug gene therapy are considered and the suitability of PCV or ACV as potential alternatives to GCV in the HSVTK system is discussed.


Assuntos
Aciclovir/análogos & derivados , Aciclovir/farmacologia , Apoptose/efeitos dos fármacos , Ganciclovir/farmacologia , Herpesvirus Humano 1/genética , Timidina Quinase/genética , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Transformada , Tamanho Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Citometria de Fluxo , Terapia Genética , Guanina , Herpesvirus Humano 1/enzimologia , Humanos , Rim/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timidina Quinase/metabolismo
12.
Cancer ; 36(6): 2206-13, 1975 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1203871

RESUMO

A case of histologically benign lymph nodal metastases from a uterine leiomyoma in a 27-year-old woman is reported. It is postulated that fragments of a leiomyoma, detached at the time of endometrial curettage, entered dilated lymphatic channels in or adjacent to a large projecting submucous leiomyoma, and seeded several pelvic and para-aortic lymph nodes. During an interval of 8 years, these grew slowly and did not infiltrate the perinodal tissues or give rise to secondary metastases.


Assuntos
Leiomioma/patologia , Neoplasias Uterinas/patologia , Adulto , Feminino , Humanos , Metástase Linfática , Inoculação de Neoplasia
13.
J Virol ; 62(10): 3892-5, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2843685

RESUMO

The establishment of mammalian and procaryotic systems which express the Epstein-Barr virus (EBV) thymidine kinase (TK) has been reported previously (E. Littler, J. Zeuthen, A. A. McBride, E. Trøst-Sørensen, K. L. Powell, J. E. Walsh-Arrand, and J. R. Arrand, EMBO J. 5:1959-1966, 1986). The EBV TK activity expressed in both of these systems was characterized by in vitro assays and found to resemble that of the herpes simplex virus TK both in its broad range of nucleoside and nucleotide utilization and also in its ability to accept antiviral nucleoside analogs as substrates. Further results are presented which suggest that these in vitro systems may prove suitable for studying the potential anti-EBV activity of other candidate antiviral compounds.


Assuntos
Herpesvirus Humano 4/enzimologia , Timidina Quinase/análise , Aciclovir/metabolismo , Animais , Linhagem Celular Transformada , Citarabina/metabolismo , Escherichia coli/enzimologia , Fosforilação , Timidina Quinase/antagonistas & inibidores , Timidina Quinase/biossíntese
14.
JAMA ; 241(2): Unknown, 1979 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-102804

RESUMO

Biological factitious, and technical reasons have previously been reported for real or apparent changes in blood type. In two cases, an apparent change in blood type resulted from a previous impersonation of the patient by a different person.


Assuntos
Antígenos de Grupos Sanguíneos , Enganação , Teste de Histocompatibilidade , Sistema ABO de Grupos Sanguíneos , Adulto , Transfusão de Sangue , Criança , Feminino , Humanos , Gravidez , Testes de Gravidez , Sistema do Grupo Sanguíneo Rh-Hr , Risco
15.
Int J Cancer ; 45(6): 1028-32, 1990 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-2161795

RESUMO

A bacterial expression system which produces large amounts of the Epstein-Barr-virus-coded thymidine kinase has been developed and used to produce protein for Western blot analysis of a number of human antisera. Interestingly, only sera from nasopharyngeal carcinoma (NPC) patients had any detectable IgA antibody which reacted with the EBV TK. These findings provided the basis for ELISA tests using a crude lysate of the E. coli cells expressing the EBV TK as target antigen. Sera from NPC patients showed high levels of IgA reactive antibodies in this test while other sera did not.


Assuntos
Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/genética , Herpesvirus Humano 4/genética , Neoplasias Nasofaríngeas/imunologia , Timidina Quinase/genética , Anticorpos Antivirais/análise , Especificidade de Anticorpos/genética , Especificidade de Anticorpos/imunologia , Western Blotting , Ensaio de Imunoadsorção Enzimática , Escherichia coli/enzimologia , Escherichia coli/imunologia , Regulação Bacteriana da Expressão Gênica/imunologia , Herpesvirus Humano 4/enzimologia , Herpesvirus Humano 4/imunologia , Humanos , Imunoglobulina A/análise , Neoplasias Nasofaríngeas/genética , Plasmídeos/genética , Plasmídeos/imunologia , Conformação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Timidina Quinase/análise , Timidina Quinase/imunologia , Proteínas Virais/análise
16.
Nucleic Acids Res ; 17(19): 7609-22, 1989 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-2552412

RESUMO

Studies of nucleic acid homology suggest the BGLF5 open reading frame of Epstein-Barr virus (EBV) encodes an alkaline deoxyribonuclease (DNase) sharing some homology with that of herpes simplex virus. We report here the expression of the BGLF5 open reading frame in E. coli and the expression of high levels of a novel alkaline DNase activity in induced cells. This alkaline DNase has been purified to apparent homogeneity as a single protein species. This is the first report of the expression of a herpesvirus coded DNase in a prokaryotic system and of the purification of the EBV DNase to demonstrable purity. It has the biochemical characteristics of a typical herpesvirus alkaline exonuclease showing a high pH optimum, an absolute requirement for Mg2+ for activity and sensitivity to high salt concentrations and polyamines. The enzyme activity was neutralized by sera from patients with nasopharyngeal carcinoma and was reactive with these sera in Western blot analysis. Thus the prokaryotic expression system described here provides an economical and efficient source of the EBV DNase for biochemical and seroepidemiological analysis.


Assuntos
Clonagem Molecular , Desoxirribonucleases/genética , Escherichia coli/genética , Genes Virais , Herpesvirus Humano 4/genética , Proteínas Estruturais Virais/genética , Western Blotting , DNA Recombinante/metabolismo , Desoxirribonucleases/biossíntese , Desoxirribonucleases/metabolismo , Indução Enzimática , Herpesvirus Humano 4/enzimologia , Cinética , Peso Molecular , Plasmídeos , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo
17.
Carcinogenesis ; 12(4): 709-12, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1849471

RESUMO

Alkylated nucleotides have been detected by 32P-postlabelling using the enzyme T4 polynucleotide kinase which phosphorylates the 3'-mononucleotides to give the 3',[5'-32P]bisphosphates. These may then be separated by two-dimensional TLC as the bisphosphates or the [5'-32P]monophosphates. We describe here an alternative approach using the Epstein-Barr virus (EBV) encoded thymidine kinase (TK) to directly phosphorylate adducted nucleosides to give the [5'-32P]monophosphates. Using a series of methyl, ethyl and butyl thymidines EBV-encoded TK was shown to phosphorylate a wide range of adducted thymidines with varying degrees of labelling efficiency; N3-methyl thymidine was labelled with the highest efficiency and O4-ethyl thymidine the lowest. Whereas O4-methyl thymidine was labelled at a higher efficiency than O2-methyl thymidine, O4-ethyl and O4-butyl thymidines were labelled at a much lower efficiency than the corresponding O2-alkyl thymidines. Labelling efficiency increased with pH in the range pH 7 to pH 9, but the relative labelling efficiency was ATP independent. This direct phosphorylation of adducted nucleosides offers an alternative approach to the detection of alkylated residues in DNA which may complement current postlabelling procedures.


Assuntos
Herpesvirus Humano 4/enzimologia , Timidina Quinase/metabolismo , Timidina/metabolismo , Trifosfato de Adenosina/metabolismo , Alquilação , Autorradiografia , Cromatografia em Camada Fina/métodos , Herpesvirus Humano 4/genética , Concentração de Íons de Hidrogênio , Cinética , Nucleosídeos/metabolismo , Radioisótopos de Fósforo , Fosforilação , Timidina/análogos & derivados , Timidina Quinase/genética
18.
Virology ; 181(1): 390-4, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1847261

RESUMO

The Epstein-Barr virus (EBV) alkaline deoxyribonuclease (DNase) was inserted into the baculovirus Autographa californica nuclear polyhedrosis virus (AcMNPV). Infection of the insect cell line Spodoptera frugiperda (SF9) with the recombinant virus led to the expression of an enzymatically active alkaline DNase. The recombinant EBV alkaline DNase was highly soluble, and the recombinant baculovirus produced approximately 10-20 mg of EBV DNase per 1 X 10(9) cells. The recombinant enzyme activity was neutralized by specific antisera to the EBV DNase and was recognized by these sera in Western blot analysis and immunofluorescence tests. The recombinant EBV DNase was neutralized by these sera from patients with nasopharyngeal carcinoma and chronic infectious mononucleosis. Western blot analysis using these patients' sera showed that IgG and IgA antibodies to the EBV DNase could be readily detected.


Assuntos
Baculoviridae/genética , Desoxirribonucleases/genética , Herpesvirus Humano 4/isolamento & purificação , Neoplasias Nasofaríngeas/diagnóstico , Animais , Western Blotting , Linhagem Celular , Desoxirribonucleases/análise , Desoxirribonucleases/metabolismo , Eletroforese em Gel de Poliacrilamida , Imunofluorescência , Herpesvirus Humano 4/enzimologia , Herpesvirus Humano 4/genética , Humanos , Cinética , Peso Molecular , Neoplasias Nasofaríngeas/microbiologia , Plasmídeos , Transfecção
19.
Nature ; 358(6382): 160-2, 1992 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-1319559

RESUMO

Human cytomegalovirus (HCMV, a betaherpes virus) is the cause of serious disease in immunologically compromised individuals, including those with acquired immunodeficiency syndrome. One of the compounds used in the chemotherapy of HCMV infections is the nucleoside analogue 9-(1,3-dihydroxy-2-propoxymethyl)-guanine (ganciclovir). The mechanism of action of this drug is dependent on the formation of the nucleoside triphosphate, which is a strong inhibitor of the viral DNA polymerase. Thymidine kinase, which is encoded by many of the herpesviruses, catalyses the initial phosphorylation of ganciclovir. But there is no evidence for the coding of this enzyme by HCMV, and DNA sequence analysis of the HCMV genome has shown that there is no open reading frame characteristic of a herpesvirus thymidine kinase. Here we present biochemical and immunological evidence that the HCMV UL97 open reading frame codes for a protein capable of phosphorylating ganciclovir. This protein seems to be responsible for the selectivity of ganciclovir and will be useful tool in the understanding and refinement of the antiviral activity of new selective anti-HCMV compounds.


Assuntos
Citomegalovirus/genética , Ganciclovir/metabolismo , Genes Virais , Fosfotransferases (Aceptor do Grupo Álcool) , Fosfotransferases/genética , Proteínas Quinases/genética , Clonagem Molecular , Expressão Gênica , Inibidores da Síntese de Ácido Nucleico , Fosforilação , Fosfotransferases/metabolismo , Plasmídeos , Proteínas Quinases/metabolismo , Proteínas Recombinantes/metabolismo , Homologia de Sequência do Ácido Nucleico
20.
J Gen Virol ; 64(Pt 5): 983-95, 1983 May.
Artigo em Inglês | MEDLINE | ID: mdl-6302216

RESUMO

The herpes simplex virus type 2 major DNA-binding protein has been functionally characterized using temperature-sensitive mutants in the complementation group 2-2. The mutants were shown to be defective in the DNA-binding protein gene by mapping the mutants to the area of the genome known to code for the protein, and by demonstrating alterations in the major DNA-binding protein induced in mutant-infected cells. The mutants were shown to be defective in the replication of virus DNA. The nature of this defect was examined by studying virus DNA synthesis in vitro and by the examination of virus enzymes. An effect of mutation in the DNA-binding protein was to destabilize both the DNA polymerase and the alkaline exonuclease.


Assuntos
DNA Helicases/genética , Simplexvirus/genética , DNA Viral/biossíntese , Proteínas de Ligação a DNA , DNA Polimerase Dirigida por DNA/biossíntese , Vírus Defeituosos/genética , Indução Enzimática , Exodesoxirribonucleases/biossíntese , Genes Virais , Teste de Complementação Genética , Marcadores Genéticos , Mutação , Temperatura
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