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2.
Sensors (Basel) ; 20(4)2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32075308

RESUMO

In this study, a sensor based on the development of a planar antenna immersed in sediments dedicated to water content monitoring in this type of material is proposed and experimentally validated. It is produced by a conventional Printed Circuit Board (PCB) manufacturing process on a double-sided metalized FR4 substrate. The sensitivity of the sensor is ensured by the variation of the real part of the complex dielectric permittivity of sediments with water content at around 1 GHz. As shown, in this frequency range, electrode polarization and Maxwell-Wagner polarization effects become negligible, leading to only a bulk water polarization sensitivity. The sensor operates in the reflection mode by monitoring the variation of the resonant frequency as a function of the sediment density through the S11 reflection measurements. An experimental sensitivity of 820   MHz . g - 1 . cm 3 was achieved. Despite the simplification of data interpretation at the considered frequency, the influence of ionic species such as NaCl in sediments on the real part of the relative complex dielectric permittivity is highlighted. This demonstrates the importance of considering a second parameter such as the S11 level at low frequency or the electrical conductivity to extract the density from the frequency measurements.

3.
Br J Psychiatry ; 212(5): 274-278, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-30517072

RESUMO

Many novel therapeutic options for depression exist that are either not mentioned in clinical guidelines or recommended only for use in highly specialist services. The challenge faced by clinicians is when it might be appropriate to consider such 'non-standard' interventions. This analysis proposes a framework to aid this decision.Declaration of interestIn the past 3 years R.H.M.W. has received support for research, expenses to attend conferences and fees for lecturing and consultancy work (including attending advisory boards) from various pharmaceutical companies including Astra Zeneca, Cyberonics, Eli Lilly, Janssen, LivaNova, Lundbeck, MyTomorrows, Otsuka, Pfizer, Roche, Servier, SPIMACO and Sunovion. D.M.B.C. has received fees from LivaNova for attending an advisory board. In the past 3 years A.J.C. has received fees for lecturing from Astra Zeneca and Lundbeck; fees for consulting from LivaNova, Janssen and Allergan; and research grant support from Lundbeck.In the past 3 years A.C. has received fees for lecturing from pharmaceutical companies namely Lundbeck and Sunovion. In the past 3 years A.L.M. has received support for attending seminars and fees for consultancy work (including advisory board) from Medtronic Inc and LivaNova. R.M. holds joint research grants with a number of digital companies that investigate devices for depression including Alpha-stim, Big White Wall, P1vital, Intel, Johnson and Johnson and Lundbeck through his mindTech and CLAHRC EM roles. M.S. is an associate at Blueriver Consulting providing intelligence to NHS organisations, pharmaceutical and devices companies. He has received honoraria for presentations and advisory boards with Lundbeck, Eli Lilly, URGO, AstraZeneca, Phillips and Sanofi and holds shares in Johnson and Johnson. In the past 3 years P.R.A.S. has received support for research, expenses to attend conferences and fees for lecturing and consultancy work (including attending an advisory board) from life sciences companies including Corcept Therapeutics, Indivior and LivaNova. In the past 3 years P.S.T. has received consultancy fees as an advisory board member from the following companies: Galen Limited, Sunovion Pharmaceuticals Europe Ltd, myTomorrows and LivaNova. A.H.Y. has undertaken paid lectures and advisory boards for all major pharmaceutical companies with drugs used in affective and related disorders and LivaNova. He has received funding for investigator initiated studies from AstraZeneca, Eli Lilly, Lundbeck and Wyeth.


Assuntos
Transtorno Depressivo Maior/terapia , Transtorno Depressivo Resistente a Tratamento/terapia , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Resistente a Tratamento/diagnóstico , Humanos
4.
Mol Psychiatry ; 21(12): 1672-1679, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27698434

RESUMO

Positron emission tomography (PET) imaging of the 18 kDa translocator protein (TSPO) has been used to investigate whether microglial activation, an indication of neuroinflammation, is evident in the brain of adults with schizophrenia. Interpretation of these studies is confounded by potential modulatory effects of antipsychotic medication on microglial activity. In the first such study in antipsychotic-free schizophrenia, we have used [11C](R)-PK11195 PET to compare TSPO availability in a predominantly antipsychotic-naive group of moderate-to-severely symptomatic unmedicated patients (n=8), similarly symptomatic medicated patients with schizophrenia taking risperidone or paliperidone by regular intramuscular injection (n=8), and healthy comparison subjects (n=16). We found no evidence for increased TSPO availability in antipsychotic-free patients compared with healthy controls (mean difference 4%, P=0.981). However, TSPO availability was significantly elevated in medicated patients (mean increase 88%, P=0.032) across prefrontal (dorsolateral, ventrolateral, orbital), anterior cingulate and parietal cortical regions. In the patients, TSPO availability was also strongly correlated with negative symptoms measured using the Positive and Negative Syndrome Scale across all the brain regions investigated (r=0.651-0.741). We conclude that the pathophysiology of schizophrenia is not associated with microglial activation in the 2-6 year period following diagnosis. The elevation in the medicated patients may be a direct effect of the antipsychotic, although this study cannot exclude treatment resistance and/or longer illness duration as potential explanations. It also remains to be determined whether it is present only in a subset of patients, represents a pro- or anti-inflammatory state, its association with primary negative symptoms, and whether there are significant differences between antipsychotics.


Assuntos
Receptores de GABA/fisiologia , Esquizofrenia/diagnóstico por imagem , Adulto , Antipsicóticos/uso terapêutico , Encéfalo/efeitos dos fármacos , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Isoquinolinas , Masculino , Microglia , Palmitato de Paliperidona , Tomografia por Emissão de Pósitrons/métodos , Risperidona , Esquizofrenia/tratamento farmacológico
6.
J Colloid Interface Sci ; 438: 306-317, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25454455

RESUMO

In this paper, a new comprehensive analysis of a suspended drop of a pure liquid evaporating into air is presented. Based on mass and energy conservation equations, a quasi-steady model is developed including diffusive and convective transports, and considering the non-isothermia of the gas phase. The main original feature of this simple analytical model lies in the consideration of the local dependence of the physico-chemical properties of the gas on the gas temperature, which has a significant influence on the evaporation process at high temperatures. The influence of the atmospheric conditions on the interfacial evaporation flux, molar fraction and temperature is investigated. Simplified versions of the model are developed to highlight the key mechanisms governing the evaporation process. For the conditions considered in this work, the convective transport appears to be opposed to the evaporation process leading to a decrease of the evaporation flux. However, this effect is relatively limited, the Péclet numbers happening to be small. In addition, the gas isothermia assumption never appears to be valid here, even at room temperature, due to the large temperature gradient that develops in the gas phase. These two conclusions are explained by the fact that heat transfer from the gas to the liquid appears to be the step limiting the evaporation process. Regardless of the complexity of the developed model, yet excluding extremely small droplets, the square of the drop radius decreases linearly over time (R(2) law). The assumptions of the model are rigorously discussed and general criteria are established, independently of the liquid-gas couple considered.

7.
Toxicol In Vitro ; 28(2): 198-208, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24516877

RESUMO

In a prior study on electronic cigarette (EC) refill fluids, Cinnamon Ceylon was the most cytotoxic of 36 products tested. The purpose of the current study was to determine if high cytotoxicity is a general feature of cinnamon-flavored EC refill fluids and to identify the toxicant(s) in Cinnamon Ceylon. Eight cinnamon-flavored refill fluids, which were screened using the MTT assay, varied in their cytotoxicity with most being cytotoxic. Human embryonic stem cells were generally more sensitive than human adult pulmonary fibroblasts. Most products were highly volatile and produced vapors that impaired survival of cells in adjacent wells. Cinnamaldehyde (CAD), 2-methoxycinnamaldehyde (2MOCA), dipropylene glycol, and vanillin were identified in the cinnamon-flavored refill fluids using gas chromatography­mass spectrometry and high-pressure liquid chromatography (HPLC). When authentic standards of each chemical were tested using the MTT assay, only CAD and 2MOCA were highly cytotoxic. The amount of each chemical in the refill fluids was quantified using HPLC, and cytotoxicity correlated with the amount of CAD/product. Duplicate bottles of the same product were similar, but varied in their concentrations of 2MOCA. These data show that the cinnamon flavorings in refill fluids are linked to cytotoxicity, which could adversely affect EC users.


Assuntos
Cinnamomum zeylanicum/química , Cinnamomum zeylanicum/toxicidade , Aromatizantes/toxicidade , Produtos do Tabaco , Acroleína/análogos & derivados , Acroleína/química , Acroleína/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Interpretação Estatística de Dados , Relação Dose-Resposta a Droga , Células-Tronco Embrionárias/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Pulmão/citologia , Pulmão/efeitos dos fármacos , Células-Tronco Neurais/efeitos dos fármacos , Espectrofotometria Ultravioleta , Sais de Tetrazólio , Tiazóis
8.
Eur J Cancer Care (Engl) ; 22(3): 300-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23279077

RESUMO

The purpose of this study was to explore the knowledge and attitudes of paid carers of people with a learning disability regarding cancer. A questionnaire was utilised to gather information from carers involved in the social care of adults with learning disabilities within the independent sector. A total of 324 questionnaires were returned. Subjects were asked to provide words that they associated with cancer to provide data on their attitude to cancer. Knowledge-based questions examined their knowledge on the possibility of recovery from cancer, the likelihood of cancer (particularly in relation to people with learning disabilities), types of cancer, risk reduction and early signs and detection. Subjects were also asked for their views regarding the adequacy of their knowledge and training needs. The findings indicated that the carers had some knowledge regarding cancer, but strategies for preventing and detecting cancer with adults with learning disabilities were not clearly elucidated.


Assuntos
Atitude Frente a Saúde , Cuidadores/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Deficiências da Aprendizagem/enfermagem , Neoplasias , Adulto , Cuidadores/economia , Feminino , Educação em Saúde/normas , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/prevenção & controle , Inquéritos e Questionários
9.
J Pharmacol Toxicol Methods ; 66(3): 238-45, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22820057

RESUMO

INTRODUCTION: Human embryonic stem cells (hESC) provide an invaluable model for assessing the effects of environmental chemicals and drugs on human prenatal development. However, hESC are difficult to adapt to 96-well plate screening assays, because they survive best when plated as colonies, which are difficult to count and plate accurately. The purpose of this study is to present an experimental method and analysis procedure to accomplish reliable screening of toxicants using hESC. METHODS: We present a method developed to rapidly and easily determine the number of cells in small colonies of hESC spectrophotometerically and then accurately dispense equivalent numbers of cells in 96-well plates. The MTT assay was used to evaluate plating accuracy, and the method was tested using known toxicants. RESULTS: The quality of the plate set-up and analysis procedure was evaluated with NIH plate validation and assessment software. All statistical parameters measured by the software were acceptable, and no drift or edge effects were observed. The 96-well plate MTT assay with hESC was tested by performing a dose-response screen of commercial products, which contain a variety of chemicals. The screen was done using single wells/dose, and the reliability of this method was demonstrated in a subsequent screen of the same products repeated three times. The single and triple screens were in good agreement, and NOAELs and IC(50)s could be determined from the single screen. The effects of vapor from volatile chemicals were studied, and methods to monitor and avoid vapor effects were incorporated into the assay. DISCUSSION: Our method overcomes the difficulty of using hESC for reliable quantitative 96-well plate assays. It enables rapid dose-response screening using equipment that is commonly available in laboratories that culture hESC. This method could have a broad application in studies of environmental chemicals and drugs using hESC as models of prenatal development.


Assuntos
Técnicas de Cultura de Células , Células-Tronco Embrionárias/efeitos dos fármacos , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Contagem de Células , Relação Dose-Resposta a Droga , Células-Tronco Embrionárias/metabolismo , Poluentes Ambientais/administração & dosagem , Humanos , Concentração Inibidora 50 , Nível de Efeito Adverso não Observado , Reprodutibilidade dos Testes , Espectrofotometria , Fatores de Tempo
10.
Chronic Dis Inj Can ; 32(1): 2-11, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22153171

RESUMO

INTRODUCTION: Identifying individuals in the prediabetic state may help delay/prevent disease progression to type 2 diabetes mellitus. We explored the feasibility of a household mailing approach for population-based screening of prediabetes and unidentified type 2 diabetes mellitus, developed standard protocol, and developed and implemented community-based lifestyle programs. METHODS: The 16-item Canadian Diabetes Risk Assessment Questionnaire (CANRISK) was mailed to every household in two rural Nova Scotia communities. In total 417 participants aged 40 to 74 years with no prior diagnosis of diabetes self-administered the CANRISK and completed a 2-hour oral glucose tolerance test (OGTT) at a local health care facility. Those with prediabetes were invited to participate in a Prediabetes Lifestyle Program. RESULTS: Glycemic status was identified as normal, prediabetes or diabetes for 84%, 13% and 3% of participants, respectively. Association between glycemic status and overall CANRISK risk score was statistically significant. Six CANRISK items were significantly associated with glycemic status: body mass index, waist circumference, history of hypertension and hyperglycemia, education and perceived health status. Participants and physicians gave positive feedback on the CANRISK screening process. CONCLUSION: The CANRISK holds promise as a population-based screening tool.


Assuntos
Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Estilo de Vida , Inquéritos e Questionários , Adulto , Idoso , Atitude do Pessoal de Saúde , Índice de Massa Corporal , Distribuição de Qui-Quadrado , Escolaridade , Feminino , Teste de Tolerância a Glucose , Conhecimentos, Atitudes e Prática em Saúde , Nível de Saúde , Humanos , Hiperglicemia/complicações , Hipertensão/complicações , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Nova Escócia , Satisfação do Paciente , Circunferência da Cintura
11.
Phys Med Biol ; 56(4): 931-49, 2011 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-21248391

RESUMO

Iterative image reconstruction methods such as ordered-subset expectation maximization (OSEM) are widely used in PET. Reconstructions via OSEM are however reported to be biased for low-count data. We investigated this and considered the impact for dynamic PET. Patient listmode data were acquired in [(11)C]DASB and [(15)O]H(2)O scans on the HRRT brain PET scanner. These data were subsampled to create many independent, low-count replicates. The data were reconstructed and the images from low-count data were compared to the high-count originals (from the same reconstruction method). This comparison enabled low-statistics bias to be calculated for the given reconstruction, as a function of the noise-equivalent counts (NEC). Two iterative reconstruction methods were tested, one with and one without an image-based resolution model (RM). Significant bias was observed when reconstructing data of low statistical quality, for both subsampled human and simulated data. For human data, this bias was substantially reduced by including a RM. For [(11)C]DASB the low-statistics bias in the caudate head at 1.7 M NEC (approx. 30 s) was -5.5% and -13% with and without RM, respectively. We predicted biases in the binding potential of -4% and -10%. For quantification of cerebral blood flow for the whole-brain grey- or white-matter, using [(15)O]H(2)O and the PET autoradiographic method, a low-statistics bias of <2.5% and <4% was predicted for reconstruction with and without the RM. The use of a resolution model reduces low-statistics bias and can hence be beneficial for quantitative dynamic PET.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Modelos Biológicos , Tomografia por Emissão de Pósitrons/métodos , Benzilaminas , Radioisótopos de Carbono , Humanos , Cinética , Método de Monte Carlo , Radioisótopos de Oxigênio , Água
12.
Hum Reprod ; 24(2): 386-97, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19043081

RESUMO

BACKGROUND: Embryonic stem cells (ESC), which originate from the inner cell mass of blastocysts, are valuable models for testing the effects of toxicants on preimplantation development. In this study, mouse ESC (mESC) were used to compare the toxicity of mainstream (MS) and sidestream (SS) cigarette smoke on cell attachment, survival and proliferation. In addition, smoke from a traditional commercial cigarette was compared with smoke from three harm-reduction brands. METHODS: MS and SS smoke solutions were made using an analytical smoking machine and tested at three doses using D3 mESC plated on 0.2% gelatin. At 6 and 24 h, images were taken and the number of attached cells was evaluated. RESULTS: Both MS and SS smoke from traditional and harm-reduction cigarettes inhibited cell attachment, survival and proliferation dose dependently. For all brands, SS smoke was more potent than MS smoke. However, removal of the cigarette filter increased the toxicity of MS smoke to that of SS smoke. Both MS and SS smoke from harm-reduction cigarettes were as inhibitory, or more inhibitory, than their counterparts from the traditional brand. When preimplantation mouse embryos were cultured for 1 h in MS or SS smoke solutions from a harm-reduction brand, blastomeres became apoptotic, in agreement with the data obtained using mESC. CONCLUSIONS: mESC provide a valuable model for toxicological studies on the preimplantation stage of development and were used to show that MS and SS smoke from traditional and harm-reduction cigarettes are detrimental to embryonic cells prior to implantation.


Assuntos
Desenvolvimento Embrionário/efeitos dos fármacos , Células-Tronco Embrionárias/efeitos dos fármacos , Redução do Dano , Nicotiana/toxicidade , Fumaça , Animais , Apoptose/efeitos dos fármacos , Blastômeros/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Camundongos
13.
Hum Reprod ; 22(2): 346-55, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17071822

RESUMO

BACKGROUND: Cigarette smoke from 2R1 research brand cigarettes and specific toxicants in smoke inhibit oviductal functioning. Our purpose was to test the hypothesis that smoke from commercial cigarettes, including harm reduction cigarettes, inhibits oviductal functioning and to measure the concentration of previously identified toxicants in smoke from research and commercial cigarettes. METHODS: Mainstream (MS) and sidestream (SS) smoke solutions from two research, six traditional commercial and three harm reduction brands were tested in vitro using an oviductal assay that measures ciliary beat frequency, oocyte retrieval rate and smooth muscle contraction. RESULTS: Generally, smoke from each brand of cigarette was inhibitory in the three oviductal bioassays. SS, the major component of environmental tobacco smoke, was usually more inhibitory than MS, the smoke inhaled by active smokers. Nine cigarette toxicants, previously shown to be highly inhibitory in the oviductal bioassays, were quantified in MS and SS. 4-Methylpyridine, which was inhibitory by itself in picomolar doses, was present in the highest concentration in MS and SS solutions from all brands tested. In general, toxicant concentrations were higher in SS than in MS solutions. CONCLUSIONS: These data show that commercial brands of cigarettes, including harm reduction cigarettes, contain toxicants that inhibit biological processes in the oviduct and could affect reproductive outcomes.


Assuntos
Tubas Uterinas/efeitos dos fármacos , Tubas Uterinas/fisiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Cílios/efeitos dos fármacos , Cílios/fisiologia , Cresóis/toxicidade , Cricetinae , Feminino , Indóis/análise , Indóis/toxicidade , Mesocricetus , Contração Muscular/efeitos dos fármacos , Nível de Efeito Adverso não Observado , Oócitos/citologia , Fenóis/análise , Fenóis/toxicidade , Picolinas/análise , Picolinas/toxicidade , Pirazinas/análise , Pirazinas/toxicidade , Piridinas/análise , Piridinas/toxicidade , Quinolinas/análise , Quinolinas/toxicidade , Coleta de Tecidos e Órgãos , Poluição por Fumaça de Tabaco/análise
14.
Eur Respir J ; 26(3): 435-41, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16135724

RESUMO

During pregnancy, patients with asthma are at risk of poor outcomes, particularly when asthma is poorly controlled. The aim of this study was to determine the level of asthma self-management skills and knowledge among pregnant subjects and describe the implementation of an asthma education programme delivered in an antenatal clinic setting. Pregnant subjects with asthma were assessed by an asthma educator at 20 (n = 211) and 33 weeks gestation (n = 149). Lung function, symptoms, medication use, adherence, knowledge and inhaler technique were assessed. They were asked whether they had a written asthma action plan, or performed peak flow monitoring. Asthma was classified as mild, moderate or severe. At the first visit with the asthma educator, 40% of females reported nonadherence to inhaled corticosteroids, inhaler technique was assessed as inadequate in 16% and 42% had inadequate medication knowledge. Peak flow monitoring was performed by 3% and 15% had a written action plan. There were significant improvements in all aspects of asthma self-management following education. In females with severe asthma, night symptoms and reliever medication use significantly decreased after education. In conclusion, during pregnancy, patients with asthma have poor asthma knowledge and skills, and may benefit from self-management education as part of their obstetric care.


Assuntos
Asma/psicologia , Asma/terapia , Conhecimentos, Atitudes e Prática em Saúde , Complicações na Gravidez/psicologia , Complicações na Gravidez/terapia , Autocuidado , Corticosteroides/administração & dosagem , Adulto , Feminino , Seguimentos , Humanos , Avaliação das Necessidades , Educação de Pacientes como Assunto , Gravidez , Resultado da Gravidez , Testes de Função Respiratória , Índice de Gravidade de Doença
15.
Toxicol Sci ; 86(1): 141-51, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15716489

RESUMO

Previously, we showed that pyridines and pyrazines in cigarette smoke inhibit oviductal functioning in vitro in nanomolar and picomolar doses. The purpose of this study was to determine the lowest observable adverse effect levels (LOAELs) of phenols, quinolines, indoles, benzene, and 2-cyclopenten-1-ones found in mainstream smoke solutions on ciliary beat frequency, oocyte pickup rate, and infundibular smooth muscle contraction using the hamster oviduct. After solid phase extraction, mainstream smoke solution fractions were tested in the oviductal assays. The active fractions were analyzed using gas chromatography-mass spectrometry to identify individual chemicals. Using this approach, benzene, eleven phenolic, two indole, two quinoline, and two 2-cyclopenten-1-one derivatives were identified in the active fractions. Commercially available authentic standards of the identified compounds were tested in dose-response studies on hamster oviducts. The LOAELs were determined for each compound using the ciliary beat frequency, oocyte pickup rate, and infundibular smooth muscle contraction rate assays. Indole, the compound with the highest potency, showed inhibition of ciliary beat frequency (10(-13) M), oocyte pickup rate (10(-14) M), and infundibular smooth muscle contraction rate (10(-15) M) in femtomolar doses. All of the other compounds tested, except phenol, which only showed inhibition at millimolar concentrations, were inhibitory in picomolar, nanomolar, or micromolar concentrations. Derivitization of phenol increased its toxicity in the oviductal assays, especially when a methyl or ethyl group was substituted on the fourth position. The indoles, quinolines, and four phenolic compounds had both high potencies and efficacies in the oviductal assays.


Assuntos
Benzeno/toxicidade , Ciclopentanos/toxicidade , Tubas Uterinas/efeitos dos fármacos , Nicotiana/química , Fenóis/toxicidade , Quinolinas/toxicidade , Fumaça/análise , Animais , Cricetinae , Relação Dose-Resposta a Droga , Feminino , Mesocricetus
16.
J Virol Methods ; 122(1): 29-36, 2004 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-15488617

RESUMO

The SARS-associated human coronavirus (SARS-HCoV) is a newly described, emerging virus conclusively established as the etiologic agent of the severe acute respiratory syndrome (SARS). This study presents a single-tube RT-PCR assay that can detect with high analytical sensitivity the SARS-HCoV, as well as several other coronaviruses including other known human respiratory coronaviruses (HCoV-OC43 and HCoV-229E). Species identification is provided by sequencing the amplicon, although a rapid screening test by restriction enzyme analysis has proved to be very useful for the analysis of samples obtained during the SARS outbreak in Toronto, Canada.


Assuntos
Infecções por Coronavirus/diagnóstico , Coronavirus/classificação , Coronavirus/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Síndrome Respiratória Aguda Grave/diagnóstico , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/isolamento & purificação , Sequência de Bases , Coronavirus/genética , Coronavirus Humano 229E/classificação , Coronavirus Humano 229E/genética , Coronavirus Humano 229E/isolamento & purificação , Infecções por Coronavirus/virologia , Coronavirus Humano OC43/classificação , Coronavirus Humano OC43/genética , Coronavirus Humano OC43/isolamento & purificação , DNA Complementar , DNA Viral/análise , DNA Viral/isolamento & purificação , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Humanos , Dados de Sequência Molecular , Filogenia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/classificação , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Sensibilidade e Especificidade , Alinhamento de Sequência , Análise de Sequência de DNA , Síndrome Respiratória Aguda Grave/virologia
17.
Eur Respir J ; 23(5): 759-62, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15176693

RESUMO

Excessive salivary contamination of induced sputum samples prevents the satisfactory examination of lower airway inflammation. The effects of salivary contamination on different sputum fluid phase measures and the levels of salivary contamination preventing analysis are not defined. The present study sought to examine this by investigating the effect of increasing salivary contamination on induced sputum samples. Sputum and saliva samples from subjects with asthma and healthy controls were collected, and treated with dithiothreitol (DTT). Saliva was then added to aliquots of dispersed sputum in increasing proportions (0% to 100%). The effect of increasing saliva contamination was assessed on sputum total cell count, viability, differential cell count and fluid phase levels of interleukin (IL)-8, eosinophil cationic protein (ECP) and total protein. The addition of saliva to induced sputum reduced total cell counts and absolute cell counts but did not change the differential cell count. Levels of fluid phase ECP and IL-8 were significantly reduced with increased salivary contamination. There was a progressive reduction in ECP and IL-8, which reached significance at 70% and 80% saliva contamination, respectively. IL-8 levels corrected for total protein showed no change with increasing saliva concentrations. Induced sputum differential cell counts expressed as the proportion of nonsquamous cells are robust measures that are not influenced by salivary contamination. Studies reporting total and absolute cell counts and fluid phase mediator levels require control for squamous contamination.


Assuntos
Asma/metabolismo , Asma/patologia , Proteínas Sanguíneas/análise , Interleucina-8/análise , Ribonucleases/análise , Saliva , Escarro/química , Escarro/citologia , Adulto , Idoso , Proteínas Sanguíneas/antagonistas & inibidores , Estudos de Casos e Controles , Contagem de Células , Proteínas Granulares de Eosinófilos , Feminino , Humanos , Interleucina-8/antagonistas & inibidores , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Ribonucleases/antagonistas & inibidores
18.
Anat Embryol (Berl) ; 208(2): 109-20, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15052477

RESUMO

Chorioallantoic membranes (CAMs) were used to determine which extracellular matrix molecules play essential roles in growth and vascular development in vivo and whether expression of critical molecules is affected by cigarette smoke exposure. Treatment of CAMs on day 5 of development with antibodies to CD44 or tenascin, but not to other matrix molecules, inhibited CAM growth and affected various aspects of blood vessel development including normal growth and branching of vessels, migration of vessels, and formation and differentiation of the capillary plexus. DNA synthesis was inhibited by antibodies to both C44 and tenascin which probably accounted for many of the phenotypic changes observed in treated CAMs. CD44 was located on all cells in day 5 CAMs, and tenascin, while present throughout the CAM, was especially abundant around large, non-migratory mesodermal blood vessels and endodermal cells that were positioned away from the direction of blood vessel migration. These data suggest that while tenascin is required for normal blood vessel migration, high levels of tenascin inhibit migration. The different distributions of CD44 and tenascin in CAMs and the observation that antibodies to either CD44 or tenascin produced similar phenotypes indicate that CD44 and tenascin were not functionally redundant. Mainstream smoke solutions, which produce a phenotype similar to that seen with anti-tenascin and anti-CD44, inhibited expression of CD44 mRNA and increased tenascin mRNA expression. 3-Ethylpyridine, a chemical in cigarette smoke that produced changes in CAM development similar to anti-CD44 and anti-tenascin treatment, also increased tenascin mRNA expression, but did not affect CD44. Together these data show that tenascin and CD44 play critical roles in early growth and vascular development of the CAM and support the idea that 3-ethylpyridine in mainstream smoke impairs CAM growth and vascular development by targeting expression of tenascin. 3-Ethylpyridine is generally regarded as safe and is used in many consumer products including food and tobacco.


Assuntos
Membrana Corioalantoide/crescimento & desenvolvimento , Receptores de Hialuronatos/farmacologia , Neovascularização Fisiológica , Tenascina/farmacologia , Poluição por Fumaça de Tabaco/efeitos adversos , Animais , Embrião de Galinha , DNA/biossíntese , Modelos Animais de Doenças , Receptores de Hialuronatos/biossíntese , Receptores de Hialuronatos/imunologia , Fenótipo , Piridinas/efeitos adversos , RNA Mensageiro/biossíntese , Tenascina/imunologia
19.
Microsc Res Tech ; 61(4): 349-57, 2003 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-12811740

RESUMO

The perivitelline space of mammalian oocytes changes in size and composition during preimplantation development. Often overlooked in the past, this space contains a hyaluronan-rich extracellular matrix prior to fertilization and a cortical granule envelope following release of the cortical granules at fertilization. The hyaluronan-containing matrix of unfertilized oocytes is well developed in some species such as opossums and humans but is scant in rodents including the hamster and mouse. The significance of the hyaluronan-rich matrix, which attaches to the plasma membrane of the oocytes, is not fully understood. However, hyaluronan, which can inhibit membrane fusion, is present in the perivitelline space (PVS) of unfertilized oocytes and must be negotiated by the fertilizing sperm. Following fertilization, the cortical granule envelope forms as the cortical granules disperse, thereby causing the PVS to increase significantly in size. Calcium is important in the dispersion of the cortical granules following exocytosis. Once formed, the cortical granule envelope in some species is about the same thickness as the zona pellucida, but it is not readily visualized unless it is stained with fluorescent probes or examined ultrastructurally after following stabilization with ruthenium red. The envelope contains proteins that remain in the PVS until the time of blastocyst hatching. Although little work has been done on the functions of the cortical granule envelope, several studies are consistent with the idea that it plays a role in blocking polyspermy. While nicotine increases polyspermy in sea urchins, its effects on polyspermy in human smokers have not been characterized, but could be addressed in human in vitro fertilization labs.


Assuntos
Fertilização/fisiologia , Oócitos/fisiologia , Zona Pelúcida/fisiologia , Animais , Cricetinae , Grânulos Citoplasmáticos/fisiologia , Grânulos Citoplasmáticos/ultraestrutura , Exocitose , Feminino , Humanos , Masculino , Microscopia Confocal , Microscopia Eletrônica , Oócitos/ultraestrutura , Interações Espermatozoide-Óvulo , Zona Pelúcida/ultraestrutura
20.
J Virol ; 77(9): 5464-74, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12692247

RESUMO

Human papillomavirus type 16 (HPV16) E6 and E7 oncoproteins are required for cellular transformation and represent candidate targets for HPV-specific and major histocompatibility complex class I-restricted CD8(+)-T-cell responses in patients with cervical cancer. Recent evidence suggests that cross-reactivity represents the inherent nature of the T-cell repertoire. We identified HLA-A2 binding HPV16 E7 variant peptides from human, bacterial, or viral origin which are able to drive CD8(+)-T-cell responses directed against wild-type HPV16 E7 amino acid 11 to 19/20 (E7(11-19/20)) epitope YMLDLQPET(T) in vitro. CD8(+) T cells reacting to the HLA-A2-presented peptide from HPV16 E7(11-19(20)) recognized also the HLA-A2 binding peptide TMLDIQPED (amino acids 52 to 60) from the human coronavirus OC43 NS2 gene product. Establishment of coronavirus NS2-specific, HLA-A2-restricted CD8(+)-T-cell clones and ex vivo analysis of HPV16 E7 specific T cells obtained by HLA-A2 tetramer-guided sorting from PBL or tumor-infiltrating lymphocytes obtained from patients with cervical cancer showed that cross-reactivity with HPV16 E7(11-19(20)) and coronavirus NS2(52-60) represents a common feature of this antiviral immune response defined by cytokine production. Zero of 10 patients with carcinoma in situ neoplasia and 3 of 18 patients with cervical cancer showed > or =0.1% HPV16 E7-reactive T cells in CD8(+) peripheral blood lymphocytes. In vivo priming with HPV16 was confirmed in patients with cervical cancer or preinvasive HPV16-positive lesions using HLA-A2 tetramer complexes loaded with the E6-derived epitope KLPQLCTEL. In contrast, we could not detect E6-reactive T cells in healthy individuals. These data imply that the measurement of the HPV16 E7(11-19(20)) CD8(+)-T-cell response may reflect cross-reactivity with a common pathogen and that variant peptides may be employed to drive an effective cellular immune response against HPV.


Assuntos
Papillomaviridae/imunologia , Sequência de Aminoácidos , Linfócitos T CD8-Positivos/imunologia , Coronavirus/imunologia , Reações Cruzadas , Epitopos de Linfócito T/imunologia , Feminino , Antígeno HLA-A2/metabolismo , Humanos , Ativação Linfocitária , Dados de Sequência Molecular , Proteínas Oncogênicas Virais , Proteínas E7 de Papillomavirus , Infecções por Papillomavirus/imunologia , Peptídeos/química , Peptídeos/genética , Peptídeos/imunologia , Infecções Tumorais por Vírus/imunologia , Neoplasias do Colo do Útero/imunologia , Proteínas não Estruturais Virais/imunologia
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