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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 47(2): 137-140, 2024 Feb 12.
Artigo em Chinês | MEDLINE | ID: mdl-38309963

RESUMO

Tuberculous tracheobronchial fistulas are caused by mediastinal or hilar tuberculous lymph nodes ulcerating into the trachea or bronchus. Patients usually require flexible bronchoscopic interventional procedures in addition to systemic anti-tuberculosis chemotherapy in the ulceration phase. In this paper, we reported 2 cases of central airway stenosis caused by tuberculous tracheobronchial fistula, which had poor treatment results after flexible bronchoscopy. According to the patients' condition, the airway lesions were treated by rigid bronchoscopy combined with flexible bronchoscopy, cryotherapy, argon plasma coagulation, and so on. The central airway stenosis was resolved quickly, and the caseating lymph node tissue was removed as much as possible under the premise of ensuring safety, which shortened the recovery time of tuberculous fistula.


Assuntos
Fístula , Tuberculose , Humanos , Broncoscopia/métodos , Constrição Patológica , Tuberculose/complicações , Tuberculose/terapia , Brônquios
2.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(6): 587-591, 2023 Jun 12.
Artigo em Chinês | MEDLINE | ID: mdl-37278173

RESUMO

The lumen-occlusion type of tracheobronchial tuberculosis is the most severe type of tracheobronchial stenosis of tuberculosis, often leading to atelectasis or even lung damage in patients. Some patients require surgical resection of the diseased airways and lungs, which can seriously affect their quality of life and even be life-threatening. In order to improve the treatment ability of bronchoscopy physicians for lumen occlusion type of tracheobronchial tuberculosis, this article retrospectively analyzed 30 cases of tracheobronchial tuberculosis with lumen occlusion in Hunan Chest Hospital, and summarized the experience of achieving better results by high-frequency electrotome combined with balloon dilatation and cryotherapy.


Assuntos
Broncopatias , Estenose Traqueal , Tuberculose , Humanos , Broncoscópios , Broncopatias/terapia , Estenose Traqueal/terapia , Dilatação/métodos , Estudos Retrospectivos , Qualidade de Vida , Broncoscopia/métodos , Crioterapia
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 44(3): 237-242, 2021 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-33721938

RESUMO

Objective: To investigate the efficacy of balloon dilatation performed for patients who suffered from actively caseating endobronchial tuberculosis (EBTB) and central airway stenosis in clinical improving period who's bronchus has not formed mature scar tissue. Methods: A total of 152 tuberculous unilateral main bronchus stenosis patients (23 male and 129 female) who received treatment in Hunan Chest Hospital from January 1st 2014 to December 31st 2018 were included in this retrospective analysis. The age was 15-66 (33.3±11.9) years old. All patients received routine anti-tuberculosis chemotherapy. Sixty-four of them who suffered from actively caseating EBTB and unilateral main bronchus stenosis received cryotherapy and endobronchial isoniazid (INH) administration till the caseating necrosis in stenotic bronchus was disappeared and ulcers were recovered, and then received balloon dilatation combined with cryotherapy, were test group. Eighty-eight of them who suffered from fibrostenotic EBTB received balloon dilatation combined with cryotherapy were control group. We analyzed the efficacy and complications after treatments. Results: The lung re-expansion rate after treatment in test group was higher than the control group, and the differences were statistically significant [74.0%(37/50) vs. 37.9%(22/58), χ²=14.094, P<0.001]. The 6-month re-stenosis rate in test group was lower than control group, and the differences were statistically significant [10.9%(7/64) vs. 30.7% (27/88), χ²=8.318, P=0.004]. The differences of diameter and diameter variation after balloon dilatation, immediate effective rates, average times of balloon dilatation and procedure-related bleeding (<10 ml) rates, chest pain rates had no statistical signification in two groups. Severe complications including fatal bleeding (>100 ml) and mediastinal emphysema did not occur during our procedures. Conclusions: Performing balloon dilatation for patients who suffered from actively caseating EBTB and central airway stenosis in the clinical improvement period, when caseous necrosis tissue disappeared and ulcers were recovered, not only helps to perform interventional procedures on distal bronchus in time, increase the rate of lung re-expansion, can also reduce the rate of re-stenosis after 6 months, so it is effective and safe.


Assuntos
Broncopatias , Tuberculose , Adolescente , Adulto , Idoso , Broncoscopia , Constrição Patológica , Dilatação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
4.
Zhonghua Liu Xing Bing Xue Za Zhi ; 41(8): 1328-1334, 2020 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-32867445

RESUMO

Objective: To understand the characteristics and differences of diarrhea-related symptoms caused by different pathogens, and the clinical features of various pathogens causing diarrhea. Methods: Etiology surveillance program was conducted among 20 provinces of China from 2010 to 2016. The acute diarrhea outpatients were collected from clinics or hospitals. A questionnaire was used to survey demographics and clinical features. VFeces samples were taken for laboratory detection of 22 common diarrhea pathogens, to detect and analyze the clinical symptom pattern characteristics of the patient's. Results: A total of 38 950 outpatients were enrolled from 20 provinces of China. The positive rates of Rotavirus and Norovirus were the highest among the five diarrhea-causing viruses (Rotavirus: 18.29%, Norovirus: 13.06%). In the isolation and culture of 17 diarrhea-causing bacterial, Escherichia coli showed the highest positive rates (6.25%). The clinical features of bacterial diarrhea and viral diarrhea were mainly reflected in the results of fecal traits and routine examination, but pathogenic Vibrio infection was similar to viral diarrhea. Conclusion: Infectious diarrhea presents different characteristics due to various symptoms which can provide a basis for clinical diagnosis.


Assuntos
Disenteria/microbiologia , Disenteria/virologia , Vigilância da População , China/epidemiologia , Disenteria/epidemiologia , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Fezes/virologia , Humanos , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação
5.
Eur Rev Med Pharmacol Sci ; 20(6): 1214-20, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049279

RESUMO

OBJECTIVE: To examine the skin whitening capabilities of shikimic acid pathway compounds and find the most effective molecule to be used as the active ingredient for skin whitening products. MATERIALS AND METHODS: Skin whitening is the practice of using chemical substances to lighten skin tone by the lessening the concentration of melanin. The whitening efficacy of shikimic acid pathway compounds was evaluated. Eight compounds in the shikimic acid pathway were chosen for this study: benzoic acid, p-coumaric acid, vanillic acid, syringic acid, quinic acid, shikimic acid, orcinol monohydrate, and phenyl pyruvic acid. We measured the tyrosinase inhibitory capacity of the compounds in the animal model of zebrafish and also evaluated the compounds' anti-oxidant activities using the DPPH radical scavenging, and ABTS+ free radical scavenging tests. Compounds' cytotoxicity effects were also evaluated. RESULTS: Amongst eight shikimic acid pathway compounds used in this study, shikimic acid was the most potent tyrosinase-inhibitor and the most efficient compound to be used as an active ingredient for skin whitening. Shikimic acid revealed a good radical scavenging activity (RAS) with low cell toxicity. CONCLUSIONS: Promising results obtained in this study may open a new window of opportunity to introduce another compound to be used in the skin-whiting cosmetics industry.


Assuntos
Melaninas/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Ácido Chiquímico/uso terapêutico , Pele/efeitos dos fármacos , Animais , Peixe-Zebra
6.
Genetika ; 49(12): 1357-63, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25438595

RESUMO

Five mitochondrial protein-encoding genes (COX1, COX2, CytB, ND4 and ND5) from the wheat midge, Sitodiplosis mosellana (Diptera: Cecidomyiidae), were sequenced and compared with those of 3 other Cecidoidae species, Mayetiola destructor, Rhopalomyia pomum and Asphondylia rosetta. These genes shared similar AT content (74.0-80.1%) and base substitution bias in favour of transversions (68.87-79.72%) over transitions (20.28-37.04%). Substitution saturation analyses indicated fast saturation of transitional substitutions in COX2, CytB, ND4 and ND5, especially at the 3rd codon positions. Analysis of interspecific divergence among the 4 species showed that the sequence divergence rates (evolutionary rates) were in the order of ND4 = CytB > COX2 = ND5 > COX1. Intraspecific genetic polymorphism analysis within the field populations of S. mosellana indicated that ND4 had the highest genetic polymorphism and COX1 the lowest. Genetic variation patterns suggested that COX1 could be used as a molecular marker for phylogenetic analysis across a relatively wide taxonomic range in Cecidomyiidae, while COX2 and ND5 may be useful for estimating relationships at a subgenus level or among closely related species. With its high genetic polymorphism, ND4 was the molecular market most suitable for population genetics studies. These findings will be valuable for our further understanding and studies in evolutionary biology and population genetics for S. mosellana and other Cecidomyiidae insects.


Assuntos
Composição de Bases , Dípteros/genética , Evolução Molecular , Genes de Insetos , Proteínas de Insetos/genética , Proteínas Mitocondriais/genética , Polimorfismo Genético , Animais , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 2/genética , Dípteros/classificação , Marcadores Genéticos , Mutação , NADH Desidrogenase/genética , Filogenia
7.
Neurology ; 77(1): 75-81, 2011 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-21700586

RESUMO

OBJECTIVE: Mutations in the PLA2G6 gene at the PARK14 locus have been reported in complicated parkinsonism. To assess the prevalence of and phenotypes associated with PLA2G6 gene mutations, we screened PLA2G6 mutations in a cohort of patients with autosomal recessive early-onset parkinsonism (AREP). METHODS: We selected 12 families with AREP in which the Parkin, PINK1, DJ-1, ATP13A2, and FBXO7 gene mutations had been previously excluded. All patients came from the mainland of China. The entire PLA2G6 coding region and exon-intron boundaries were sequenced from genomic DNA templates. We then performed PET studies on individuals in the pedigree with a homozygous PLA2G6 mutation, and investigated the enzyme activity level of the mutation. RESULTS: A homozygous missense mutation, c.G991T (p.D331Y), was identified in an autosomal recessive case. A younger sister of the p.D331Y-carrying patient was also homozygous for the mutation, but with no extrapyramidal symptoms. A PET study showed a substantial reduction in dopamine transporter (DAT) binding in the p.D331Y patient, and a slight reduction in DAT binding in his sister. In vitro, we experimentally demonstrate that the D331Y mutation caused an approximately 70%reduction in enzyme activity. CONCLUSIONS: We have confirmed that the PLA2G6 gene allocated PARK14 locus and is associated with AREP.


Assuntos
Fosfolipases A2 do Grupo VI/genética , Mutação de Sentido Incorreto/genética , Transtornos Parkinsonianos/genética , Adulto , Animais , Povo Asiático/genética , Linhagem Celular Transformada , Estudos de Coortes , Análise Mutacional de DNA , Saúde da Família , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Proteínas de Fluorescência Verde/genética , Humanos , Masculino , Transtornos Parkinsonianos/diagnóstico por imagem , Fosforilcolina/farmacologia , Piperazinas , Tomografia por Emissão de Pósitrons/métodos , Piridinas , Antagonistas da Serotonina , Transfecção/métodos
8.
Radiat Prot Dosimetry ; 144(1-4): 199-201, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21310735

RESUMO

The effects of UV-induced bleaching of deep traps on Harshaw thermoluminescent (TL) LiF:Mg,Cu,P and LiF:Mg,Ti materials were investigated. During a normal heating cycle, LiF:Mg,Cu,P is limited to a maximum temperature of 240 °C. LiF:Mg,Ti can be read to higher temperatures; however, encapsulation in polytetrafluoroethylene limits the maximum readout temperature to 300 °C. Generally, for both materials, these respective temperatures are sufficient for emptying traps corresponding to the main dosemetric peaks. However, when the dosemeters are subjected to a high dose level, such as 1 Gy (much higher than individual monitoring dose levels), higher temperature traps are filled that cannot be emptied without exceeding the above-mentioned maximum temperatures. These high temperature traps tend to be unstable during normal readout and can significantly increase the residual TL signal. The purpose of this study was to investigate the applicability of a UV-induced bleaching technique for emptying higher temperature traps following high-dose applications. In addition, in the case of LiF:Mg,Cu,P, where the maximum readout temperature is significantly lower, we investigated the possibility of reducing the residual signal using the application of repeated readout cycles. The optical bleaching approach was found to be effective in the case of LiF:Mg,Ti; however, for LiF:Mg,Cu,P, no reduction in the residual signal was observed. For this latter material, the application of repeatable readout cycles is very effective and residual signals equivalent to dose levels as low as 0.01 mGy were observed following an initial dose of 5 Gy. To the best of our knowledge, this work is the first attempt to apply an 'optical annealing' technique to the Harshaw thermoluminescent dosemeter (TLD) materials.


Assuntos
Cobre/análise , Fluoretos/análise , Compostos de Lítio/análise , Magnésio/análise , Fósforo/análise , Monitoramento de Radiação/instrumentação , Proteção Radiológica/instrumentação , Dosimetria Termoluminescente/instrumentação , Titânio/análise , Calibragem , Desenho de Equipamento , Humanos , Luz , Teste de Materiais , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Temperatura , Dosimetria Termoluminescente/métodos , Fatores de Tempo , Raios Ultravioleta
9.
Oncogene ; 29(29): 4183-93, 2010 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-20498637

RESUMO

Cancer cells often have unstable genomes and increased centrosome and chromosome numbers, which are an important part of malignant transformation in the most recent model of tumorigenesis. However, very little is known about divisional failures in cancer cells that may lead to chromosomal and centrosomal amplifications. In this study, we show that cancer cells often failed at cytokinesis because of decreased phosphorylation of the myosin regulatory light chain (MLC), a key regulatory component of cortical contraction during division. Reduced MLC phosphorylation was associated with high expression of myosin phosphatase and/or reduced myosin light-chain kinase levels. Furthermore, expression of phosphomimetic MLC largely prevented cytokinesis failure in the tested cancer cells. When myosin light-chain phosphorylation was restored to normal levels by phosphatase knockdown, multinucleation and multipolar mitosis were markedly reduced, resulting in enhanced genome stabilization. Furthermore, both overexpression of myosin phosphatase or inhibition of the myosin light-chain kinase in nonmalignant cells could recapitulate some of the mitotic defects of cancer cells, including multinucleation and multipolar spindles, indicating that these changes are sufficient to reproduce the cytokinesis failures we see in cancer cells. These results for the first time define the molecular defects leading to divisional failure in cancer cells.


Assuntos
Citocinese , Cadeias Leves de Miosina/metabolismo , Neoplasias/patologia , Linhagem Celular Tumoral , Polaridade Celular , Humanos , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Quinase de Cadeia Leve de Miosina/antagonistas & inibidores , Fosfatase de Miosina-de-Cadeia-Leve/análise , Fosfatase de Miosina-de-Cadeia-Leve/fisiologia , Neoplasias/metabolismo , Fosforilação
10.
Radiat Prot Dosimetry ; 125(1-4): 93-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17223631

RESUMO

The Harshaw TLD system has three key calibration procedures: the Reader, the Dosemeter and the Algorithm. These functions must be properly calibrated for the system to achieve the optimum results. For the conventional reader and dosemeter calibration, Harshaw TLD recommends a pre-fade and a post-fade of 24-48 h when calibrating the system for LiF:Mg,Ti type dosemeter. It is also recommended that keeping the fade time consistent is important to maintain the quality of the system performance. In recent years, new calibration features have been introduced into the Harshaw TLD models 6600 and 8800 operating systems. These new features are Auto Calibration, Auto QC and Auto Blank, and they give the user the ability to set up the clear-expose-read process to be performed automatically in a sequence for each dosemeter. This saves processing time and keeps the fade time the same. However, since the fade time is near zero, will it affect the TLD system calibration factors? What should the user expect? This paper presents a study of the effect of Auto Calibration/Auto QC to the TLD operation.


Assuntos
Exposição Ocupacional/análise , Proteção Radiológica/instrumentação , Proteção Radiológica/normas , Dosimetria Termoluminescente/instrumentação , Carga Corporal (Radioterapia) , Calibragem , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Internacionalidade , Exposição Ocupacional/prevenção & controle , Controle de Qualidade , Eficiência Biológica Relativa , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dosimetria Termoluminescente/normas , Estados Unidos
11.
Radiat Prot Dosimetry ; 123(3): 329-36, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17132668

RESUMO

A new type of extremity dosemeter, which incorporates the Harshaw TLD EXTRAD dosemeter element into a PVC finger stall, has been developed. The dosemeter uses high-sensitivity lithium fluoride, (7)LiF:Mg,Cu,P (TLD-700H) in a thin 7 mg cm(-2) layer, with alternative coverings of PVC at 10 mg cm(-2) and aluminised polyester at 3.2 mg cm(-2). Results are presented of the type testing of both versions of the finger stall dosemeter against published standards.


Assuntos
Dedos , Dosimetria Termoluminescente/instrumentação , Relação Dose-Resposta à Radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dosimetria Termoluminescente/métodos
12.
Radiat Prot Dosimetry ; 119(1-4): 248-54, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16835277

RESUMO

LiF:Mg,Cu,P is starting to replace LiF:Mg,Ti in a variety of personnel dosimetry applications. LiF:Mg,Cu,P has superior characteristics as compared to LiF:Mg,Ti including, higher sensitivity, improved energy response for photons, lack of supralinearity and insignificant fading. The use of LiF:Mg,Cu,P in large scale dosimetry programs is of particular interest due to the extreme sensitivity of this material to the maximum readout temperature, and the variety of different dosimetry aspects and details that must be considered for a successful implementation in routine dosimetry. Here we discuss and explain the various aspects of large scale LiF:Mg,Cu,P based dosimetry programs including the properties of the TL material, new generation of TLD readers, calibration methodologies, a new generation of dose calculation algorithms based on the use of artificial neural networks and the overall uncertainty of the dose measurement. The United States Navy (USN) will be the first US dosimetry processor who will use this new material for routine applications. Until June 2002, the Navy used two types of thermoluminescent materials for personnel dosimetry, CaF2:Mn and LiF:Mg,Ti. A program to upgrade the system and to implement LiF:Mg,Cu,P, started in the mid 1990s and was recently concluded. In 2002, the new system replaced the LiF:Mg,Ti and is scheduled to start replacing the CaF2:Mn system in 2006. A pilot study to determine the dosimetric performance of the new LiF:Mg,Cu,P based dosimetry system was recently completed, and the results show the new system to be as good or better than the current system in all areas tested. As a result, LiF:Mg,Cu,P is scheduled to become the primary personnel dosimeter for the entire US Navy in 2006.


Assuntos
Fluoretos/química , Fluoretos/efeitos da radiação , Compostos de Lítio/química , Compostos de Lítio/efeitos da radiação , Proteção Radiológica/instrumentação , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/tendências , Cobre/química , Cobre/efeitos da radiação , Relação Dose-Resposta à Radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Previsões , Magnésio/química , Magnésio/efeitos da radiação , Fósforo/química , Fósforo/efeitos da radiação , Doses de Radiação , Proteção Radiológica/métodos , Dosimetria Termoluminescente/métodos , Estados Unidos
13.
Radiat Prot Dosimetry ; 120(1-4): 303-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16835278

RESUMO

The Harshaw Model 6600 Plus is a reader with a capacity for 200 TLD cards or 800 extremity cards. The new unit integrates more functionality, and significantly automates the QC and calibration process compared to the Model 6600. The Model 6600 Plus was tested against the IEC 61066 (1991-2012) procedures using Harshaw TLD-700H and TLD-600H, LiF:Mg,Cu,P based TLD Cards. An overview of the type testing procedures is presented. These include batch homogeneity, detection threshold, reproducibility, linearity, self-irradiation, residue, light effects on dosemeter, light leakage to reader, voltage and frequency, dropping and reader stability. The new TLD reader was found to meet all the IEC criteria by large margins and appears well suited for whole body, extremity and environmental dosimetry applications, with a high degree of dosimetric performance.


Assuntos
Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/normas , Desenho de Equipamento , Análise de Falha de Equipamento , Doses de Radiação , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
14.
Radiat Prot Dosimetry ; 119(1-4): 184-90, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16581930

RESUMO

The glow curve shape of LiF:Mg,Cu,P (MCP) material is studied in this research. The study is focused on the effects of the heating rate on the dosimetric peaks. Different configurations of dosemeters (chips, cards and powder) are studied. The shifting of the dominant dosimetric peak is observed and analysed. The curves are deconvoluted using the new Harshaw Glow Curve Analyser (GCA) program. Results of the study are presented, as well as possible explanations as to the observed effects.


Assuntos
Fluoretos/química , Fluoretos/efeitos da radiação , Temperatura Alta , Compostos de Lítio/química , Compostos de Lítio/efeitos da radiação , Modelos Químicos , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/métodos , Simulação por Computador , Cobre/química , Cobre/efeitos da radiação , Relação Dose-Resposta à Radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Cinética , Magnésio/química , Magnésio/efeitos da radiação , Teste de Materiais , Fósforo/química , Fósforo/efeitos da radiação , Doses de Radiação
15.
Radiat Prot Dosimetry ; 119(1-4): 255-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16581931

RESUMO

Harshaw TLD-700H (7LiF:Mg,Cu,P) was previously characterised for low- to high-dose ranges from 1 microGy to 20 Gy. This paper describes the studies and results of dose-response and linearity at much higher doses. TLD-700H is a near perfect dosimetric material with near tissue equivalence, flat energy response, and the ability to measure beta, gamma and X rays. These new results extend the applicability of Harshaw TLD-700H into more dosimetric measurement environments. The simple glow curve structure provides insignificant fade, eliminating special oven preparation methods experienced by other materials. The work presented in this paper quantifies the performance of Harshaw TLD-700H in extended ranges.


Assuntos
Fluoretos/química , Fluoretos/efeitos da radiação , Compostos de Lítio/química , Compostos de Lítio/efeitos da radiação , Modelos Químicos , Dosimetria Termoluminescente/instrumentação , Dosimetria Termoluminescente/métodos , Simulação por Computador , Cobre/química , Cobre/efeitos da radiação , Relação Dose-Resposta à Radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Magnésio/química , Magnésio/efeitos da radiação , Teste de Materiais , Fósforo/química , Fósforo/efeitos da radiação , Doses de Radiação
16.
Radiat Prot Dosimetry ; 120(1-4): 324-30, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16644944

RESUMO

One of the advantages of LiF based thermoluminescent (TL) materials is its tissue-equivalent property. The Harshaw TLD-100H (LiF:Mg,Cu,P) material has demonstrated that it has a near-flat photon energy response and high sensitivity. With the optimized dosemeter filters built into the holder, the Harshaw TLD-100H two-element dosemeter can be used as a whole body personnel dosemeter for gamma, X ray and beta monitoring without the use of an algorithm or correction factor. This paper presents the dose performance of the Harshaw TLD-100H two-element dosemeter against the ANSI N13.11-2001 standard and the results of tests that are required in IEC 1066 International Standard.


Assuntos
Fluoretos/química , Fluoretos/efeitos da radiação , Compostos de Lítio/química , Compostos de Lítio/efeitos da radiação , Dosimetria Termoluminescente/instrumentação , Relação Dose-Resposta à Radiação , Análise de Falha de Equipamento , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Dosimetria Termoluminescente/métodos
17.
Radiat Prot Dosimetry ; 101(1-4): 211-6, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12382737

RESUMO

Evaluation of a new extremity dosemeter is presented. The dosemeter is a passive device that is easy to wear and features a permanent individual numerical ID with barcode, a watertight case, an automatic TLD reader and database management software. Two dosemeters were studied: the first consists of a 100 mg x cm(-2) 7LiF:Mg,Ti (TLD-700) chip and a 42 mg x cm(-2) cap, the other consists of a 7 mg x cm(-2) layer of 7LiF:Mg,Cu,P (TLD-700H) powder and a 5 mg x cm(-2) cap. Sensitivity, repeatability, lower limit detection, angular responses and energy responses for these dosemeters are studied and presented. The dose calculation algorithm is developed and its dosimetric performance accuracy is compared with the standard ANSI N13.32-1995, Performance Testing of Extremity Dosemeters.


Assuntos
Radioisótopos de Césio , Dosimetria Termoluminescente/métodos , Partículas beta , Cobre , Fluoretos , Compostos de Lítio , Magnésio , Modelos Teóricos , Fósforo , Sensibilidade e Especificidade , Titânio
18.
Virology ; 174(1): 70-8, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1688475

RESUMO

Strains of vesicular stomatitis virus, New Jersey serotype (VSV-NJ), isolated from diseased cattle or swine were examined by genomic RNA sequencing for genetic diversity potentially leading to antigenic variations in their type-specific glycoproteins as determined by reactivity with epitope-specific monoclonal antibodies (MAbs). Seven field isolates recovered in Colorado, New Mexico, Georgia, and Mexico during the widespread 1982-1985 epizootic in the western United States resembled the prototypic 1952 Hazelhurst subtype by partial sequence homology, but amino acid reversions to the 1949 Ogden subtype occurred frequently. When studies were performed with MAbs directed to the Ogden subtype glycoprotein, relatively limited antigenic variation, and only in neutralization epitope VIII, was noted among two of five epizootic isolates from Colorado and New Mexico. However, amino acid differences in the glycoprotein of a 1983 isolate from an enzootic region of Georgia resulted in major antigenic deficiencies in epitopes V, VI, and VII as determined by Western blotting and neutralization of infectivity with epitope-specific MAbs. Quite a few genetic but no antigenic differences were noted in an enzootic 1984 isolate from Mexico, a potential origin of the United States epizootic. Marked or complete loss of epitopes VII, VI, VIII, and V can be traced to spontaneous mutations leading to amino acid substitutions at glycoprotein positions 199, 263, 275, and 317, respectively, in the enzootic Georgia isolate 07/83-GA-P and the epizootic New Mexico isolate 06/85-NM-B. By comparison, closely adjacent amino acid substitutions at glycoprotein positions 210, 268, 277, and 364 occurred in epitope-deficient mutants selected for resistance to neutralization by MAbs specific for epitopes VII, VI, VIII, and V, respectively. Two neutralization epitopes designated X and XI were found to be unique for the G protein of the 1952 Hazelhurst isolate..../52-GA-P. The epitope X-specific MAb H21, in particular, failed to neutralize the infectivity not only of the Ogden subtype..../49-UT-B but also was ineffective against all the 1982-1985 field isolates. The classical 1952 Hazelhurst strain of VSV-NJ is genetically and antigenically quite different from those viruses isolated during the 1982-1985 epizootic.


Assuntos
Variação Antigênica/genética , Antígenos Virais/genética , Glicoproteínas de Membrana , RNA Viral/genética , Vesiculovirus/imunologia , Proteínas do Envelope Viral/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Surtos de Doenças/veterinária , Epitopos/genética , México/epidemiologia , Dados de Sequência Molecular , Estomatite/epidemiologia , Estomatite/microbiologia , Estomatite/veterinária , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Estados Unidos/epidemiologia , Vesiculovirus/genética , Proteínas do Envelope Viral/imunologia , Viroses/epidemiologia , Viroses/microbiologia , Viroses/veterinária
19.
J Virol ; 63(6): 2841-3, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2542594

RESUMO

The matrix (M) protein of vesicular stomatitis virus serves as an endogenous inhibitor of viral transcription, a function missing or deficient in M proteins of temperature-sensitive (ts) mutants assigned to complementation group III. Previous studies with mutant tsO23(III) and vaccinia virus M-gene expression vectors revealed that the temperature-sensitive phenotype is due to a mutation leading to substitution of phenylalanine for leucine at amino acid III, whereas loss of the major antigenic determinant (epitope 1) of the mutant M protein results from the substitution of glutamic acid for the wild-type amino acid glycine at position 21 (Y. Li, L. Luo, R. M. Snyder, and R. R. Wagner, J. Virol. 62:3729-3737, 1988). We demonstrate here that transcription inhibition activity is restored to rescued tsO23 virus only when the rescuing vaccinia virus recombinant expresses M protein with glycine and not glutamic acid at amino acid 21. These experiments indicate the importance of the conformational integrity of the amino-terminal domain in determining the capacity of the vesicular stomatitis virus M protein to down regulate endogenous transcription.


Assuntos
Regulação da Expressão Gênica , Vetores Genéticos , Transcrição Gênica , Vírus da Estomatite Vesicular Indiana/genética , Proteínas da Matriz Viral/genética , Western Blotting , Marcadores Genéticos , Mutação , Fenótipo , Plasmídeos , Temperatura , Transfecção
20.
J Virol ; 62(10): 3729-37, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2458488

RESUMO

Full-length cDNA copies of mRNAs coding for the matrix (M) proteins of vesicular stomatitis virus and its mutant tsO23(III) were cloned in pBSM13- (BlueScribe). The authenticity of these clones was demonstrated by restriction enzyme mapping, DNA sequencing, and in vitro transcription and translation to identify the two M proteins by Western immunoblotting with epitope-specific monoclonal antibodies. Site-directed mutants were constructed by primer extension of synthetic oligodeoxynucleotides with one or two nucleotide changes to alter the glycine at amino acid 21 of the wild-type (wt) M gene to glutamic acid, alanine, or proline. Similarly, a revertant was created in the M gene of mutant tsO23 by a Glu-21----Gly substitution. A series of wt- and mutant-M-gene chimeras was also constructed to create mutant and revertant clones with Leu----Phe and His----Tyr alterations at amino acids 111 and 227, respectively. We then moved the wt and tsO23 M genes and their site-specific mutants and chimeras cloned in pBSM13- into the eucaryotic expression vector pTF7 directed by the T7 bacteriophage RNA polymerase of the vaccinia virus recombinant vTF1-6,2. Western blot analysis of the M proteins transiently expressed in CV-1 cells by plasmids carrying M genes altered at amino acid 21 revealed that the critical antigenic determinant (epitope 1) is expressed only by the Gly-21 M protein and not by Glu-21, Ala-21, or Pro-21 M proteins. Of particular interest is an apparent conformational change, evidenced by slightly but significantly retarded electrophoretic migration, in plasmid-expressed M proteins with amino acids substituted for glycine at position 21. The glutamic acid at position 21 of tsO23 is not responsible for its temperature-sensitive phenotype, because a tsO23 revertant plasmid with glycine substituted at position 21 fails to rescue tsO23 virus in cells infected at the restrictive temperature; conversely, plasmids expressing wt M protein with substitutions of glutamic acid, alanine, or proline at position 21 are just as effective in marker rescue of tsO23 as is the Gly-21 wt M protein. Marker rescue experiments with wt- and mutant-M-gene chimeras support the hypothesis of K. Morita, R. Vanderoef, and J. Lenard (J. Virol. 61:256-263, 1987) that the temperature-sensitive phenotype of tsO23 is due to a phenylalanine substituted for leucine at amino acid 111, rather than the His-227----Tyr substitution or the Gly-21----Glu substitution, which independently accounts for the loss of epitope 1 in the mutant M protein of tsO23.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Antígenos Virais/genética , Vetores Genéticos , Vírus da Estomatite Vesicular Indiana/genética , Proteínas da Matriz Viral/genética , Animais , Sequência de Bases , Linhagem Celular , Quimera , Clonagem Molecular , DNA Viral/genética , Epitopos/genética , Regulação da Expressão Gênica , Genes Virais , Genótipo , Dados de Sequência Molecular , Mutação , Fenótipo , Plasmídeos , Temperatura , Vírus Vaccinia/genética , Vírus da Estomatite Vesicular Indiana/imunologia
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