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1.
Mult Scler ; 21(8): 1013-24, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25680984

RESUMO

BACKGROUND AND OBJECTIVE: We explored which clinical and biochemical variables predict conversion from clinically isolated syndrome (CIS) to clinically definite multiple sclerosis (CDMS) in a large international cohort. METHODS: Thirty-three centres provided serum samples from 1047 CIS cases with at least two years' follow-up. Age, sex, clinical presentation, T2-hyperintense lesions, cerebrospinal fluid (CSF) oligoclonal bands (OCBs), CSF IgG index, CSF cell count, serum 25-hydroxyvitamin D3 (25-OH-D), cotinine and IgG titres against Epstein-Barr nuclear antigen 1 (EBNA-1) and cytomegalovirus were tested for association with risk of CDMS. RESULTS: At median follow-up of 4.31 years, 623 CIS cases converted to CDMS. Predictors of conversion in multivariable analyses were OCB (HR = 2.18, 95% CI = 1.71-2.77, p < 0.001), number of T2 lesions (two to nine lesions vs 0/1 lesions: HR = 1.97, 95% CI = 1.52-2.55, p < 0.001; >9 lesions vs 0/1 lesions: HR = 2.74, 95% CI = 2.04-3.68, p < 0.001) and age at CIS (HR per year inversely increase = 0.98, 95% CI = 0.98-0.99, p < 0.001). Lower 25-OH-D levels were associated with CDMS in univariable analysis, but this was attenuated in the multivariable model. OCB positivity was associated with higher EBNA-1 IgG titres. CONCLUSIONS: We validated MRI lesion load, OCB and age at CIS as the strongest independent predictors of conversion to CDMS in this multicentre setting. A role for vitamin D is suggested but requires further investigation.


Assuntos
Esclerose Múltipla/patologia , Adulto , Estudos de Coortes , Progressão da Doença , Endonucleases , Feminino , Seguimentos , Humanos , Imunoglobulina G/análise , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/líquido cefalorraquidiano , Proteínas Nucleares/análise , Bandas Oligoclonais/genética , Valor Preditivo dos Testes , Prognóstico , Medição de Risco , Análise de Sobrevida , Vitamina D/sangue
2.
Acta Neurol Scand ; 128(5): 321-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23465040

RESUMO

OBJECTIVES: Biomarkers with the potential for longitudinal measurements are needed in multiple sclerosis (MS). Urine is easy to collect, and repeated sampling is possible. METHODS: 39 paired CSF and urine samples were taken. Oligoclonal bands (OCBs) were measured in CSF. Kappa and lambda free light chain (FLC), neopterin and ubiquitin C-terminal hydrolase-L1 (UCHL1) were measured in CSF and urine. RESULTS: 16/39 samples had OCBs unique to the CSF. CSF FLC levels (P < 0.0001) were higher in OCB-positive subjects, with no difference in urinary FLC. CSF and urinary FLC did not correlate. There were a significant correlation between total CSF FLC and CSF neopterin in MS samples (correlation coefficient = 0.588, P = 0.016) and a strong correlation between CSF lambda FLC and CSF neopterin in MS samples (correlation coefficient = 0.875, P < 0.001). There was a strong correlation between urinary neopterin/creatinine levels and urinary total FLC/protein levels (correlation coefficient = 0.452, P = 0.004). Only three CSF samples (8%) had detectable levels of UCHL1. 18/38 (48%) (8/15 MS and 10/23 control) urine samples had detectable levels of UCLH1. CONCLUSIONS: This study confirms the relationship between CSF OCBs and CSF FLCs, highlighting the importance of intrathecal B- and plasma-cell activation in MS. There is a relationship between CSF FLC and CSF neopterin in MS, highlighting the multifaceted immune activation seen in MS. Correlations in the OCB-positive group highlight the multifaceted immune activation seen in MS. Further studies are required to evaluate CSF and urinary biomarkers.


Assuntos
Biomarcadores/líquido cefalorraquidiano , Biomarcadores/urina , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/urina , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Cadeias Leves de Imunoglobulina/líquido cefalorraquidiano , Cadeias Leves de Imunoglobulina/urina , Masculino , Pessoa de Meia-Idade , Neopterina/líquido cefalorraquidiano , Neopterina/urina , Bandas Oligoclonais/líquido cefalorraquidiano , Estatística como Assunto , Ubiquitina Tiolesterase/líquido cefalorraquidiano , Ubiquitina Tiolesterase/urina , Adulto Jovem
3.
J Virol Methods ; 156(1-2): 89-95, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19028524

RESUMO

A one-step reverse transcription quantitative real-time polymerase chain reaction (RT-QPCR) method in combination with RNase treatment and low copy number samples was developed in order to examine the effect of temperature on the ability of virus capsids to protect their RNA content. The method was applied to a non-cultivable virus (GII.4 norovirus) and Feline calicivirus vaccine strain F-9 (FCV) which is often used as a norovirus surrogate. Results demonstrated that FCV RNA is exposed maximally after 2min at 63.3 degrees C and this correlated with a greater than 4.5log reduction in infectivity as assessed by plaque assay. In contrast human GII.4 norovirus RNA present in diluted clinical specimens was not exposed maximally until 76.6 degrees C, at least 13.3 degrees C greater than that for FCV. These data suggest that norovirus possesses greater thermostability than this commonly used surrogate. Further, these studies indicate that current food processing regimes for pasteurisation are insufficient to achieve inactivation of GII.4 NoVs. The method provides a novel molecular method for predicting virus infectivity.


Assuntos
Calicivirus Felino/patogenicidade , Norovirus/patogenicidade , Inativação de Vírus , Animais , Calicivirus Felino/crescimento & desenvolvimento , Capsídeo/efeitos dos fármacos , Gatos , Temperatura Alta , Humanos , Modelos Biológicos , Norovirus/crescimento & desenvolvimento , Valor Preditivo dos Testes , RNA Viral/análise , RNA Viral/efeitos dos fármacos , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Ribonucleases/farmacologia , Ensaio de Placa Viral
4.
J Hum Nutr Diet ; 22(3): 246-54, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19493026

RESUMO

BACKGROUND: Obesity and being underweight in pregnancy are related to an increased risk of maternal and foetal morbidity, yet their prevalence is often unknown. The present study aimed to identify neighbourhoods with a higher than average prevalence or 'hot spots' of obesity and/or being underweight among first trimester pregnant women. METHODS: A database was compiled consisting of postcode, height and weight for 7981 women who had booked-in for antenatal care between July 2004 and June 2005 at Liverpool Women's Hospital. Body mass index (BMI) was calculated and women were categorised accordingly. Postcodes for 6865 cases across Merseyside were converted to geolocations (pin-points on a map) using conversion software (http://www.census.ac.uk/cdu/). RESULTS: There was a very high prevalence of being overweight (27%) and obesity (17%); 3.8% of women were underweight and probably malnourished (BMI < 18.5 kg m(-2)); and a further 10.7% of women were possibly malnourished (BMI < 20.0 kg m(-2). Deriving case density from the geolocations allowed visualisation and identification of six neighbourhoods with above average levels of obesity and three neighbourhoods had marked concentrations of both being underweight and obesity. CONCLUSIONS: These neighbourhoods, particularly those identified as 'hot spots' for both being underweight and obesity, include some of the most deprived wards in the UK. As dietetic intervention may help to promote optimal weight gain during pregnancy and improve dietary intake for pregnant women and their families, primary health care providers should target these localities with a high prevalence of low and high BMI as a priority.


Assuntos
Obesidade/epidemiologia , Complicações na Gravidez/epidemiologia , Magreza/epidemiologia , Adulto , Índice de Massa Corporal , Inglaterra/epidemiologia , Feminino , Humanos , Desnutrição/complicações , Desnutrição/epidemiologia , Obesidade/complicações , Sobrepeso/epidemiologia , Gravidez , Prevalência , Características de Residência , Fatores Socioeconômicos , Magreza/complicações , Saúde da População Urbana
5.
Can Commun Dis Rep ; 44(1): 1-5, 2018 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-29770090

RESUMO

The Federal/Provincial/Territorial (FPT) Public Health Response Plan for Biological Events was developed for the Public Health Network Council (PHNC). This plan outlines how the national response to public health events caused by biological agents will be conducted and coordinated, with a focus on implementation of responses led by senior-level FPT public health decision-makers. The plan was developed by an expert task group and was approved by PHNC in October, 2017. The plan describes roles, responsibilities and authorities of FPT governments for public health and emergency management, a concept of operations outlining four scalable response levels and a governance structure that aims to facilitate an efficient, timely, evidence-informed and consistent approach across jurisdictions. Improving effective engagement amongst public health, health care delivery and health emergency management authorities is a key objective of the plan.

6.
Clin Obes ; 7(4): 239-244, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28557355

RESUMO

Obstructive sleep apnoea (OSA) is an often-overlooked diagnosis, more prevalent in the obese population. Screening method accuracy, uptake and hence diagnosis is variable. There is limited data available regarding the obese pregnant population; however, many studies highlight potential risks of apnoeic episodes to mother and foetus, including hypertension, diabetes and preeclampsia. A total of 162 women with a body mass index (BMI) ≥ 35 were recruited from a tertiary referral hospital in the northwest of England. They were invited to attend three research antenatal clinics, completing an Epworth Sleepiness Scale (ESS) questionnaire at each visit. A monitor measuring the apnoea hypopnoea index (AHI) was offered at the second visit. Data taken from consent forms, hospital notes and hospital computer records were collated and anonymized prior to statistical analysis. A total of 12.1% of women had an ESS score of >10, suggesting possible OSA. Rates increased throughout pregnancy, although unfortunately, the attrition rate was high; 29.0% of women used the RUSleeping (RUS) meter, and only one (2.1%) met pre-specified criteria for OSA (AHI ≥ 15). This individual had OSA categorized as severe and underwent investigations for preeclampsia, eventually delivering by emergency caesarean section due to foetal distress. The accuracy of the ESS questionnaire, particularly the RUS monitor, to screen for OSA in the pregnant population remains unclear. Further research on a larger sample size using more user-friendly technology to confidently measure AHI would be beneficial. There are currently no guidelines regarding screening for OSA in the obese pregnant population, yet risks to both mother and foetus are well researched.


Assuntos
Obesidade Mórbida/complicações , Complicações na Gravidez/diagnóstico , Apneia Obstrutiva do Sono/diagnóstico , Adulto , Índice de Massa Corporal , Feminino , Humanos , Gravidez , Fatores de Risco
7.
Clin Obes ; 6(1): 79-88, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26781604

RESUMO

UNLABELLED: The 'Fit for Birth' study aimed to explore patterns of gestational weight gain and their relationship with pregnancy outcomes. The study had three aims: 1. To explore the feasibility of conducting a large cohort study in this setting. 2. To describe patterns of weight gain through pregnancy in obese women. 3. To explore associations of weight change during pregnancy with outcomes. STUDY POPULATION: Pregnant women with a BMI ≥ 30 kg m(-2) at first antenatal clinic visit. METHODS: This was a single centre pilot observational study based at the Liverpool Women's Hospital, a large UK maternity hospital.Women were recruited into the study at their antenatal booking visit and had weights measured throughout pregnancy. Patterns of weight gain were described and related to maternal and neonatal outcomes. MAIN OUTCOME MEASURE: The primary outcome was a composite measure consisting of any of 12 adverse maternal and foetal outcomes. This was compared by categorized pregnancy weight gain (<0 kg, 0-5 kg, 5.1-9 kg and >9 kg). RESULTS: Eight hundred and twenty four women consented to participation between June 2009 and June 2010. Weight data were collected on 756 women. Only 385 women had weights measured in all three study assessment periods (6-20 weeks, 20 + 1 to 32 weeks and >32 weeks gestation) while 427 women had weights measured in period 3. Individual patterns of weight gain varied widely and missing data were common and non-random. There was a significant association between increased weight gain during pregnancy and poor maternal and foetal outcome. CONCLUSIONS: Weight gain in obese women during pregnancy can be highly variable. Our study supports an association between increased weight gain in pregnancy and adverse perinatal outcomes.


Assuntos
Obesidade/fisiopatologia , Complicações na Gravidez/fisiopatologia , Resultado da Gravidez , Adulto , Feminino , Humanos , Gravidez , Gestantes , Estudos Prospectivos , Reino Unido , Aumento de Peso , Adulto Jovem
8.
J Bone Miner Res ; 15(3): 557-63, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10750571

RESUMO

The effects of pregnancy on bone turnover and the potential risk of developing an osteoporotic fracture in pregnancy are controversial. Utilizing biochemical markers of bone formation and resorption and dual-energy X-ray absorptiometry (DEXA), bone turnover before, during, and after pregnancy was studied in detail. Ten women (mean age 30 years; range 23-40) were recruited. Prepregnancy data were obtained and then a review was performed at 2-week intervals , once pregnancy was confirmed, until 14 weeks of gestation and thereafter monthly until term. Bone mineral density (BMD) was estimated by DEXA scanning of hip, spine, and forearm preconception and postpartum. In addition, BMD of the forearm at 14 weeks and 28 weeks gestation was obtained. All pregnancies had a successful outcome. Urinary free pyridinium cross-links, free pyridinoline (fPyr) and free deoxypyridinoline (fDPyr), were normal prepregnancy (mean [+/-SD]) 14.6 nmol/mmol (1.8) and 5.0 nmol/mmol (1.0) creat, respectively. By 14 weeks, they had increased to 20.8 nmol/mmol (4.3) and 6.1 nmol mmol (1.4) (both p < 0.02) and by 28 weeks to 26.3 nmol/mmol (5.6) and 7.4 nmol/mmol (1.6) (both p < 0.01). The ratio of fPyr to fDPyr remained constant. A similar significant increase was observed in N-telopeptide (NTx). Bone formation was assessed by measurement of carboxyterminal propeptide of type 1 collagen (P1CP) and bone-specific alkaline phosphatase (BSAP). Neither were altered significantly before 28 weeks, but subsequently mean P1CP increased from 110 microg/liter (23) to 235 microg/liter (84) at 38 weeks and mean BSAP increased from 11.1 U/liter (5.0) to 28.6 U/liter (11.1) (p < 0.01 for both variables). Lumbar spine (L1-L4) BMD decreased from a prepregnancy mean of 1.075 g/cm (0.115) to 1.054 g/cm2 (0.150) postpartum (p < 0.05). Total hip BMD decreased from a prepregnancy mean of 0.976 g/cm2 (0.089) to 0.941 g/cm2 (0.097) (p < 0.05). Forearm BMD at midradius, one-third distal and ultradistal decreased but did not reach statistical significance. As assessed by these bone markers, in the first 2 trimesters of pregnancy, bone remodeling is uncoupled with a marked increase in bone resorption. A corresponding increase in formation markers is not observed until the third trimester. Spinal BMD exhibits a significant decrease from prepregnancy to the immediate postpartum period with a mean reduction in BMD of 3.5 % in 9 months.


Assuntos
Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Cálcio/metabolismo , Gravidez/metabolismo , Absorciometria de Fóton , Adulto , Fosfatase Alcalina/sangue , Aminoácidos/urina , Biomarcadores , Reabsorção Óssea/diagnóstico por imagem , Reabsorção Óssea/etiologia , Colágeno/sangue , Colágeno Tipo I , Feminino , Fraturas Espontâneas/epidemiologia , Quadril/diagnóstico por imagem , Homeostase , Humanos , Isoenzimas/sangue , Osteoporose/etiologia , Peptídeos/sangue , Trimestres da Gravidez , Compostos de Piridínio/urina , Cintilografia , Rádio (Anatomia)/diagnóstico por imagem , Risco , Coluna Vertebral/diagnóstico por imagem
9.
Am J Clin Nutr ; 71(6): 1582-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10837302

RESUMO

BACKGROUND: Acute phase proteins (APPs) are associated with malaria-induced hyporetinemia (serum retinol <0.70 micromol/L); however, the degree of the association is not well documented. OBJECTIVE: The association between malaria-induced hyporetinemia and APPs was assessed. DESIGN: In a cross-sectional study, 90 children with serum retinol concentrations from <0.35 to >1.05 micromol/L were selected from children in a clinical trial of vitamin A supplementation. Serum was collected before treatment allocation. Retinol binding protein (RBP) concentrations were determined by radioimmunoassays, and transthyretin, alpha(1)-acid glycoprotein (AGP), alpha(1)-antichymotrypsin, C-reactive protein (CRP), haptoglobin, and albumin concentrations by radial immunodiffusion assays. RESULTS: Children in the subsample had high rates of splenomegaly and Plasmodium-positive blood-smear slides (P < 0.01); AGP (Pearson's r = -0.40, P < 0.001) and CRP (r = -0.21, P = 0.04) were inversely correlated with retinol. The negative APPs RBP, transthyretin, and albumin were positively and significantly associated with retinol. All APPs, except alpha(1)-antichymotrypsin, were significantly correlated with splenomegaly. Of the positive APPs, AGP correlated with CRP (r = 0.37, P < 0.001), indicating chronic inflammation. In a stepwise regression analysis, 73% of retinol's variability was explained by RBP and transthyretin. The model predicted that a 1-SD increase in RBP or transthyretin increases retinol by approximately 0.38 or 0.47 micromol/L, respectively, whereas an equivalent increase in AGP decreases retinol by 0.12 micromol/L. CONCLUSIONS: The RBP-transthyretin transport complex of retinol is not altered by inflammation. Positive APPs are useful markers of type and severity of inflammation; however, except for AGP, it is unlikely that they can correct for malaria-induced hyporetinemia.


Assuntos
Proteínas de Fase Aguda/análise , Malária Falciparum/epidemiologia , Vitamina A/sangue , Animais , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Malária Falciparum/sangue , Malária Falciparum/complicações , Masculino , Morbidade , Papua Nova Guiné/epidemiologia , Plasmodium falciparum/isolamento & purificação , Pré-Albumina/análise , Proteínas de Ligação ao Retinol/análise , Esplenomegalia , Deficiência de Vitamina A/etiologia
10.
Obstet Gynecol ; 101(6): 1307-11, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12798541

RESUMO

OBJECTIVE: To assess the maternal response to low molecular weight heparin during pregnancy, by estimation of plasma anti-Xa activity, at three specified gestation points and in the nonpregnant state. METHODS: A longitudinal, prospective, observational study was set in a tertiary referral recurrent miscarriage clinic. Twenty-four women, attending consecutively, were invited to participate and gave informed consent. Each woman had a history of recurring pregnancy loss and positive preconception screening for antiphospholipid syndrome. After confirmation of a viable pregnancy all subjects began taking 5000 IU of dalteparin once daily subcutaneously. Serial measurement of plasma anti-Xa activity after administration of dalteparin was performed at three standard gestation points (12, 24, and 36 weeks) and in the nonpregnant state (6 weeks postpartum). RESULTS: Peak anti-Xa levels occurred at 4 hours postbolus in pregnancy, as compared with 2 hours in the nonpregnant state. The mean anti-Xa levels at 12, 24, and 36 weeks' gestation were significantly reduced, at 2 hours postinjection, as compared with the nonpregnant state (P <.001, P <.01, P <.001, respectively). The lowest dose-response curve was at 36 weeks' gestation. A repeated-measures analysis of variance found a significant difference (P <.05) between the 36-week group and the postterm group but not between any of the other groups. CONCLUSION: During pregnancy, differences in the pharmacokinetics of low molecular weight heparin were observed, with an overall reduction in anti-Xa activity. On the basis of this study it is questionable to extrapolate dosing and lack of dose monitoring, in pregnant women, using data derived from a nonpregnant population.


Assuntos
Anticoagulantes/administração & dosagem , Dalteparina/administração & dosagem , Inibidores do Fator Xa , Aborto Habitual/prevenção & controle , Análise de Variância , Anticoagulantes/farmacocinética , Área Sob a Curva , Dalteparina/farmacocinética , Relação Dose-Resposta a Droga , Fator Xa/metabolismo , Feminino , Humanos , Estudos Longitudinais , Gravidez
11.
Talanta ; 25(2): 61-72, 1978 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18962210

RESUMO

Methods developed and employed in the recent literature (1969-1975) for the detection and determination of tungsten in a wide variety of matrices are reviewed. This paper is a supplement to the books, monographs and review papers which deal with the earlier literature.

12.
Talanta ; 18(9): 865-72, 1971 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18960957

RESUMO

In acidic solution only molybdenum(VI), tungsten(VI), vanadium(V), niobium(V) and tantalum(V) form stable, anionic complexes with dilute hydrogen peroxide. This fact has been used in developing an analytical method of separating molybdenum(VI), tungsten(VI) and vanadium(V) from other metal ions and from each other. Preliminary investigations using reversed-phase paper chromatography and solvent extraction led to a reversed-phase column Chromatographic separation technique. These metal-peroxy anions are retained by a column containing a liquid anion-exchanger (General Mills Aliquat 336) in a solid support. Then molybdenum(VI), tungsten(VI) and vanadium(V) are selectively eluted with aqueous solutions containing dilute hydrogen peroxide and varying concentrations of sulphuric acid.

13.
Talanta ; 21(12): 1281-6, 1974 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18961597

RESUMO

Studies were made of the solvent extraction of cadmium(II) from hydrochloric acid into a tri-n-octylamine-cyclohexene mixture. Distribution ratios, as a function of amine and acid concentration, were determined and this information was used to establish optimum extraction conditions and the probable nature of the extracted species. This system was used as the basis for the development of a reversed-phase column chromatographic technique for preconcentrating Cd(II). The amine-cyclohexene phase was coated on an inert macroreticular resin (XAD-2) to provide a stable column. With this system, Cd(II) in acidified water samples as large as 31. may be concentrated to 10 ml and determined by conventional atomic absorption. Interferences were studied, and the method was applied to the analysis of fresh-water streams for Cd(II).

14.
J R Coll Physicians Edinb ; 41(4): 319-22, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22184569

RESUMO

Enteric granulomatous inflammation can be caused by a number of conditions including Crohn's disease, sarcoidosis, enteric infections, chronic granulomatous disease and also by drug reactions. Granulomas have also been described in microscopic colitis associated with certain medications and autoimmune diseases. The association of granulomatous ileocolitis with coeliac disease is not common. We present a case of coeliac disease with granulomatous ileocolitis with follow-up and repeat histology on a gluten-free diet. We discuss the pathological mechanisms leading to the association of granulomatous ileocolitis with coeliac disease as well as other conditions.


Assuntos
Doença Celíaca/complicações , Doença de Crohn/complicações , Granuloma/complicações , Inflamação/etiologia , Doença Celíaca/dietoterapia , Doença Celíaca/patologia , Doença de Crohn/patologia , Dieta Livre de Glúten , Feminino , Seguimentos , Granuloma/patologia , Humanos , Pessoa de Meia-Idade
15.
J Virol Methods ; 174(1-2): 7-11, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21414362

RESUMO

The aim of this study was to develop a method for investigating the stability of the human NoV capsid in response to disinfectants and sanitisers (virucides) as an indirect method for determining virus infectivity. Capsid destruction or "virolysis" was measured using the reverse transcribed quantitative PCR (RT-QPCR) reaction in conjunction with RNase treatment (in order to destroy any exposed RNA). Two commercially available alcohol based handwashes, alcohols (75% (v/v) ethanol or isopropanol), quaternary ammonium compounds (0.14% BAC or 0.07% DIDAC), and chlorine dioxide (200 ppm) were all ineffective at promoting virolysis of human norovirus present in dilute clinical samples at the concentrations tested. GII.4 NoVs were sensitive to a combination of heat and alkali. These data show that NoVs present in dilute stool samples are resistant to virolysis using virucides that are used commonly.


Assuntos
Desinfetantes/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Norovirus/efeitos dos fármacos , 2-Propanol/farmacologia , Compostos Clorados/farmacologia , Etanol/farmacologia , Humanos , Óxidos/farmacologia , Compostos de Amônio Quaternário/farmacologia , RNA Viral/genética , RNA Viral/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribonucleases/metabolismo
16.
J Food Prot ; 74(12): 2113-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22186052

RESUMO

The relationship between the infectivity of the feline calicivirus (FCV) vaccine strain F-9 and capsid destruction (virolysis) in response to available chlorine was investigated under standardized light soil disinfection conditions. Virolysis was measured using RNase pretreatment (in order to destroy exposed RNA following chlorine treatment) and quantitative reverse transcription PCR. A comparison between the results of plaque assays and virolysis following exposure of FCV F-9 grown in tissue culture to different concentrations of available chlorine showed a similar log-linear relationship, with >4-log reductions occurring at 48 and 66 ppm, respectively. Three non-epidemiologically linked human GII.4 noroviruses (NoVs) present in dilute clinical samples showed behavior similar to each other and were 10 times more resistant to virolysis than cultured FCV F-9. FCV F-9 when present in dilute human GII.4 samples acquired increased resistance to virolysis approaching that of human NoVs. This study represents a direct comparison between the virolysis of a surrogate virus (FCV F-9) and that of human GII.4 NoVs within the same matrix in response to available chlorine. The results support the view that matrix effects have a significant effect on virus survival.


Assuntos
Calicivirus Felino/patogenicidade , Cloro/farmacologia , Desinfetantes/farmacologia , Norovirus/patogenicidade , Inativação de Vírus , Animais , Calicivirus Felino/crescimento & desenvolvimento , Proteínas do Capsídeo/efeitos dos fármacos , Contaminação de Alimentos , Microbiologia de Alimentos , Humanos , Norovirus/efeitos dos fármacos , Norovirus/crescimento & desenvolvimento , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos
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