Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 163
Filtrar
1.
Obes Sci Pract ; 4(5): 417-426, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30338112

RESUMEN

OBJECTIVE: There are conflicting data regarding the association between body mass index (BMI) and health-related quality of life (HRQoL), especially among certain population subgroups and for mental and physical health domains. METHODS: This study analysed the relationship between BMI and HRQoL (Patient-Reported Outcomes Measurement Information System mental and physical health scales) using ordinary least squares regression. Each model allowed for the possibility of a non-linear relationship between BMI and the outcome, adjusting for age, gender, comorbidities, diet and physical activity. RESULTS: A total of 10,133 respondents were predominantly female (71.7%), White (84.1%), median age of 52.1 years (interquartile range 37.2-63.3) and median BMI of 27.9 (interquartile range 24.0-33.2). In adjusted models, BMI was significantly associated with physical and mental HRQoL (p < 0.001). For physical HRQoL, there was a significant interaction with age (p = 0.02). For mental HRQoL, there was a significant interaction with sex (p = 0.0004) but not age (p = 0.7). CONCLUSIONS: This study demonstrates a non-linear association of variable clinical relevance between BMI and HRQoL after adjusting for demographic factors and comorbidities. The relationship between BMI and HRQoL is nuanced and impacted by gender and age. These findings challenge the idea of obesity as a main driver of reduced HRQoL, particularly among women and with respect to mental HRQoL.

2.
J Dev Orig Health Dis ; 8(3): 370-381, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28327211

RESUMEN

Placental transport of vitamin D and other nutrients (e.g. amino acids, fats and glucose) to the fetus is sensitive to maternal and fetal nutritional cues. We studied the effect of maternal calorific restriction on fetal vitamin D status and the placental expression of genes for nutrient transport [aromatic T-type amino acid transporter-1 (TAT-1); triglyceride hydrolase/lipoprotein uptake facilitator lipoprotein lipase (LPL)] and vitamin D homeostasis [CYP27B1; vitamin D receptor (VDR)], and their association with markers of fetal cardiovascular function and skeletal muscle growth. Pregnant sheep received 100% total metabolizable energy (ME) requirements (control), 40% total ME requirements peri-implantation [PI40, 1-31 days of gestation (dGA)] or 50% total ME requirements in late gestation (L, 104-127 dGA). Fetal, but not maternal, plasma 25-hydroxy-vitamin D (25OHD) concentration was lower in PI40 and L maternal undernutrition groups (P<0.01) compared with the control group at 0.86 gestation. PI40 group placental CYP27B1 messenger RNA (mRNA) levels were increased (P<0.05) compared with the control group. Across all groups, higher fetal plasma 25OHD concentration was associated with higher skeletal muscle myofibre and capillary density (P<0.05). In the placenta, higher VDR mRNA levels were associated with higher TAT-1 (P<0.05) and LPL (P<0.01) mRNA levels. In the PI40 maternal undernutrition group only, reduced fetal plasma 25OHD concentration may be mediated in part by altered placental CYP27B1. The association between placental mRNA levels of VDR and nutrient transport genes suggests a way in which the placenta may integrate nutritional cues in the face of maternal dietary challenges and alter fetal physiology.


Asunto(s)
Restricción Calórica/efectos adversos , Trastornos Nutricionales en el Feto/metabolismo , Desnutrición/metabolismo , Intercambio Materno-Fetal/fisiología , Efectos Tardíos de la Exposición Prenatal/metabolismo , Vitamina D/metabolismo , Animales , Femenino , Trastornos Nutricionales en el Feto/etiología , Feto , Desnutrición/complicaciones , Músculo Esquelético/metabolismo , Embarazo , Distribución Aleatoria , Ovinos
3.
J Periodontal Res ; 52(3): 636-643, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28177125

RESUMEN

BACKGROUND AND OBJECTIVE: The oral microbiome may help to maintain systemic health, including how it affects blood glucose levels; however, direct evidence linking the oral microbiome with diabetes is lacking. MATERIAL AND METHODS: We compared the oral microbiome profiles of 98 participants with incident diabetes, 99 obese non-diabetics and 97 normal weight non-diabetics, via deep sequencing of the 16S rRNA gene. RESULTS: We found that the phylum Actinobacteria was present significantly less abundant among patients with diabetes than among the controls (p = 3.9 × 10-3 ); the odds ratio (OR) and 95% confidence interval (CI) was 0.27 (0.11-0.66) for those individuals who had relative abundance higher than the median value. Within this phylum, five families and seven genera were observed, and most of them were less abundant among patients with diabetes. Notably, genera Actinomyces and Atopobium were associated with 66% and 72% decreased risk of diabetes with p-values of 8.9 × 10-3 and 7.4 × 10-3 , respectively. Stratified analyses by race showed that most taxa in this phylum were associated with diabetes in both black and white participants. This phylum was also less abundant among non-diabetic obese subjects compared to normal weight individuals, particularly genera Mobiluncus, Corynebacterium and Bifidobacterium, which showed p < 0.05. CONCLUSION: Our study revealed that multiple bacteria taxa in the phylum Actinobacteria are associated with the risk of type 2 diabetes. Some are also associated with the prevalence of obesity, suggesting that the oral microbiome may play an important role in diabetes etiology.


Asunto(s)
Diabetes Mellitus Tipo 2/etiología , Microbiota , Boca/microbiología , Actinobacteria/genética , Actinomyces/genética , Adulto , Anciano , Bifidobacterium/genética , Estudios de Casos y Controles , Corynebacterium/genética , Diabetes Mellitus Tipo 2/microbiología , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , Persona de Mediana Edad , Obesidad/microbiología , ARN Ribosómico 16S/genética , Factores de Riesgo
4.
Ann Oncol ; 27(7): 1329-36, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27217540

RESUMEN

BACKGROUND: While studies have shown that poor oral health status may increase the risk of cancer, evidence of a specific association with the risk of colorectal cancer (CRC) is inconclusive. We evaluated the association between oral health and CRC risk using data from three large cohorts: the Shanghai Men's Health Study (SMHS), the Shanghai Women's Health Study (SWHS), and the Southern Community Cohort Study (SCCS), and carried out a meta-analysis of results from other relevant published studies. PATIENTS AND METHODS: This study applied a nested case-control study design and included 825 cases/3298 controls from the SMHS/SWHS and 238 cases/2258 controls from the SCCS. The association between oral health status (i.e. tooth loss/tooth decay) and CRC risk was assessed using conditional logistic regression models. A meta-analysis was carried out based on results from the present study and three published studies. RESULTS: We found that tooth loss was not associated with increased risk of CRC. ORs and respective 95% CIs associated with loss of 1-5, 6-10, and >10 teeth compared with those with full teeth are 0.87 (0.69-1.10), 0.93 (0.70-1.24), and 0.85 (0.66-1.11) among SMHS/SWHS participants; and 1.13 (0.72-1.79), 0.87 (0.52-1.43), and 1.00 (0.63-1.58) for those with loss of 1-4, 5-10, and >10 teeth among SCCS participants. Data regarding tooth decay were available in the SCCS, but were not associated with CRC risk. Meta-analysis confirmed the null association between tooth loss/periodontal disease and CRC risk (OR 1.05, 95% CI 0.86-1.29). CONCLUSION: In this analysis of three cohorts and a meta-analysis, we found no evidence supporting an association between oral health and CRC risk.


Asunto(s)
Neoplasias Colorrectales/epidemiología , Salud Bucal , Higiene Bucal/efectos adversos , Pérdida de Diente/epidemiología , China/epidemiología , Neoplasias Colorrectales/patología , Femenino , Humanos , Modelos Logísticos , Masculino , Factores de Riesgo , Pérdida de Diente/patología
5.
Scand J Med Sci Sports ; 25 Suppl 4: 29-33, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26589114

RESUMEN

Carbohydrates (CHO) are a key source of energy for contracting skeletal muscle during strenuous exercise and fatigue during such exercise often coincides with CHO depletion. Our current understanding of the importance of CHO for exercise metabolism has its foundations in classic studies in the early 20th century by Scandinavian physiologists and Bengt Saltin contributed significantly to that tradition. This brief review summarizes our contemporary understanding of key aspects of muscle glycogen and glucose metabolism during exercise, through the lens of seminal studies by Bengt Saltin.


Asunto(s)
Glucemia/metabolismo , Ejercicio Físico/fisiología , Glucógeno/metabolismo , Músculo Esquelético/metabolismo , Carbohidratos de la Dieta/metabolismo , Glucogenólisis , Humanos , Contracción Muscular
6.
FASEB J ; 28(8): 3384-95, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24732133

RESUMEN

Some gene deletions or mutations have little effect on metabolism and metabolic adaptation because of redundancy and/or compensation in metabolic pathways. The mechanisms for redundancy and/or compensation in metabolic adaptation in mammalian cells are unidentified. Here, we show that in mouse muscle and myogenic cells, compensatory regulation of the histone deacetylase (HDAC5) transcriptional repressor maintains metabolic integrity. HDAC5 phosphorylation regulated the expression of diverse metabolic genes and glucose metabolism in mouse C2C12 myogenic cells. However, loss of AMP-activated protein kinase (AMPK), a HDAC5 kinase, in muscle did not affect HDAC5 phosphorylation in mouse skeletal muscle during exercise, but resulted in a compensatory increase (32.6%) in the activation of protein kinase D (PKD), an alternate HDAC5 kinase. Constitutive PKD activation in mouse C2C12 myogenic cells regulated metabolic genes and glucose metabolism. Although aspects of this response were HDAC5 phosphorylation dependent, blocking HDAC5 phosphorylation when PKD was active engaged an alternative compensatory adaptive mechanism, which involved post-transcriptional reductions in HDAC5 mRNA (-93.1%) and protein. This enhanced the expression of a specific subset of metabolic genes and mitochondrial metabolism. These data show that compensatory regulation of HDAC5 maintains metabolic integrity in mammalian cells and reinforces the importance of preserving the cellular metabolic adaptive response.


Asunto(s)
Adaptación Fisiológica/fisiología , Metabolismo Energético/fisiología , Regulación Enzimológica de la Expresión Génica/fisiología , Histona Desacetilasas/fisiología , Músculo Esquelético/enzimología , Mioblastos/metabolismo , Condicionamiento Físico Animal/fisiología , Proteína Quinasa C/fisiología , Proteínas Quinasas Activadas por AMP/genética , Proteínas Quinasas Activadas por AMP/fisiología , Acetilación , Animales , Línea Celular , Activación Enzimática , Glucosa/metabolismo , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/biosíntesis , Histona Desacetilasas/genética , Ratones , Ratones Endogámicos C57BL , Contracción Muscular , Fosforilación , Mutación Puntual , Proteína Quinasa C/genética , Procesamiento Proteico-Postraduccional , ARN Mensajero/biosíntesis , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/genética , Transducción de Señal/fisiología , Transcripción Genética/fisiología , Transgenes
7.
Epidemiol Infect ; 142(10): 2057-64, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24398184

RESUMEN

M. fortuitum is a rapidly growing mycobacterium associated with community-acquired and nosocomial wound, soft tissue, and pulmonary infections. It has been postulated that water has been the source of infection especially in the hospital setting. The aim of this study was to determine if municipal water may be the source of community-acquired or nosocomial infections in the Brisbane area. Between 2007 and 2009, 20 strains of M. fortuitum were recovered from municipal water and 53 patients' isolates were submitted to the reference laboratory. A wide variation in strain types was identified using repetitive element sequence-based PCR, with 13 clusters of ⩾2 indistinguishable isolates, and 28 patterns consisting of individual isolates. The clusters could be grouped into seven similar groups (>95% similarity). Municipal water and clinical isolates collected during the same time period and from the same geographical area consisted of different strain types, making municipal water an unlikely source of sporadic human infection.


Asunto(s)
Infecciones Comunitarias Adquiridas/microbiología , ADN Ribosómico/genética , Agua Potable/microbiología , Infecciones por Mycobacterium no Tuberculosas/microbiología , Mycobacterium fortuitum/genética , ARN Ribosómico 16S/genética , Infecciones de los Tejidos Blandos/microbiología , Tuberculosis Pulmonar/microbiología , Australia , Infecciones Comunitarias Adquiridas/transmisión , Femenino , Humanos , Secuencias Repetitivas Esparcidas/genética , Masculino , Infecciones por Mycobacterium no Tuberculosas/transmisión , Mycobacterium fortuitum/aislamiento & purificación , Reacción en Cadena de la Polimerasa , Infecciones de los Tejidos Blandos/transmisión , Tuberculosis Pulmonar/transmisión , Abastecimiento de Agua
8.
Syst Appl Microbiol ; 35(5): 326-33, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22742879

RESUMEN

This study compared virulence and antibiotic resistance traits in clinical and environmental Enterococcus faecalis and Enterococcus faecium isolates. E. faecalis isolates harboured a broader spectrum of virulence determinants compared to E. faecium isolates. The virulence traits Cyl-A, Cyl-B, Cyl-M, gel-E, esp and acm were tested and environmental isolates predominantly harboured gel-E (80% of E. faecalis and 31.9% of E. faecium) whereas esp was more prevalent in clinical isolates (67.8% of E. faecalis and 70.4% of E. faecium). E. faecalis and E. faecium isolated from water had different antibiotic resistance patterns compared to those isolated from clinical samples. Linezolid resistance was not observed in any isolates tested and vancomycin resistance was observed only in clinical isolates. Resistance to other antibiotics (tetracycline, gentamicin, ciprofloxacin and ampicillin) was detected in both clinical and water isolates. Clinical isolates were more resistant to all the antibiotics tested compared to water isolates. Multi-drug resistance was more prevalent in clinical isolates (71.2% of E. faecalis and 70.3% of E. faecium) compared to water isolates (only 5.7% E. faecium). tet L and tet M genes were predominantly identified in tetracycline-resistant isolates. All water and clinical isolates resistant to ciprofloxacin and ampicillin contained mutations in the gyrA, parC and pbp5 genes. A significant correlation was found between the presence of virulence determinants and antibiotic resistance in all the isolates tested in this study (p<0.05). The presence of antibiotic resistant enterococci, together with associated virulence traits, in surface recreational water could be a public health risk.


Asunto(s)
Enterococcus faecalis/efectos de los fármacos , Enterococcus faecalis/patogenicidad , Enterococcus faecium/efectos de los fármacos , Enterococcus faecium/patogenicidad , Infecciones por Bacterias Grampositivas/microbiología , Microbiología del Agua , Antibacterianos/farmacología , Distribución de Chi-Cuadrado , Farmacorresistencia Bacteriana , Enterococcus faecalis/genética , Enterococcus faecium/genética , Genes Bacterianos , Humanos , Incidencia , Pruebas de Sensibilidad Microbiana
9.
Diabetes Obes Metab ; 14(8): 768-71, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22340256

RESUMEN

The aim of the study was to determine the effect of a single bout of exercise on GLUT4 gene expression in muscle of patients with type 2 diabetes (T2D) and control subjects, matched for age and body mass index. Nine patients with T2D and nine control subjects performed 60 min of cycling exercise at ~55% peak power (W(max) ). Skeletal muscle biopsies were obtained at baseline, immediately post and 3-h post exercise. GLUT4 mRNA expression increased (p < 0.05) to a similar extent immediately post exercise in control (~60%) and T2D (~66%) subjects, and remained elevated (p < 0.05) 3-h post exercise with no differences between groups. Similarly, p-AMP-activated protein kinase, p38 mitogen-activated kinase and proliferator-activated receptor gamma co-activator-alpha mRNA expression were increased (p < 0.05) post exercise, and were not different between the groups. In conclusion, a single bout of exercise increased skeletal muscle GLUT4 mRNA expression in patients with T2D to a similar extent as in control subjects.


Asunto(s)
Diabetes Mellitus Tipo 2/metabolismo , Ejercicio Físico , Transportador de Glucosa de Tipo 4/metabolismo , Músculo Esquelético/patología , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/patología , Femenino , Expresión Génica , Transportador de Glucosa de Tipo 4/genética , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Factores de Transcripción
11.
Diabetes Obes Metab ; 13(10): 959-62, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21615668

RESUMEN

We investigated the effects of exercise training on adipose tissue and skeletal muscle GLUT4 expression in patients with type 2 diabetes (T2D). Muscle and adipose tissue samples were obtained before and after 4-weeks of exercise training in seven patients with T2D [47 ± 2 years, body mass index (BMI) 28 ± 2]. Seven control subjects (54 ± 4, BMI 30 ± 2) were recruited for baseline comparison. Adipose tissue GLUT4 protein expression was 43% lower (p < 0.05) in patients with T2D compared with control subjects and exercise training increased (p < 0.05) adipose tissue GLUT4 expression by 36%. Skeletal muscle GLUT4 protein expression was not different between control subjects and patients with T2D. Exercise training increased (p < 0.05) skeletal muscle GLUT4 protein expression by 20%. In conclusion, 4-weeks of exercise training increased GLUT4 expression in adipose tissue and skeletal muscle of patients with T2D, although the functional benefits of this adaptation appear to be dependent on an optimal ß-cell function.


Asunto(s)
Tejido Adiposo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Terapia por Ejercicio , Transportador de Glucosa de Tipo 4/metabolismo , Músculo Esquelético/metabolismo , Tejido Adiposo/fisiopatología , Índice de Masa Corporal , Diabetes Mellitus Tipo 2/fisiopatología , Femenino , Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiopatología
12.
Drug Test Anal ; 3(9): 539-43, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20882583

RESUMEN

Recently, cocaine has been concealed by dissolving it in alcohol and then transporting it in solution through ports and airports. At the present time it is very difficult to detect cocaine in this form in these environments. However, it has been shown that Raman spectroscopy can successfully detect the presence of these drugs without removing specimens from their containers. Using two portable 785 nm instruments and a 1064 nm laboratory-based instrument, several common containers used in smuggling were analyzed with varying concentrations of cocaine in ethanol solutions. The presence of cocaine is detectable to about 6% w/v in most containers. Green glass presents a problem at 785 nm due to fluorescence but by switching to 1064 nm this can be removed. To apply this technique to real samples as met within law enforcement scenarios, cocaine was dissolved in a selection of dark and white rums including Lamb's Navy Rum(™) , Brugal Añejo(™) , Bacardi(™) and Captain Morgan(™) ; cocaine was detected in all these rum solutions.


Asunto(s)
Bebidas Alcohólicas/análisis , Cocaína/análisis , Espectrometría Raman/métodos , Etanol/química , Embalaje de Productos , Sensibilidad y Especificidad
13.
J Clin Microbiol ; 49(1): 367-72, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20980566

RESUMEN

A single nucleotide polymorphism (SNP) genotyping method for Enterococcus faecalis and Enterococcus faecium was developed using the "Minimum SNPs" program. SNP sets were interrogated using allele-specific real-time PCR. SNP typing subdivided clonal complexes 2 and 9 of E. faecalis and 17 of E. faecium, members of which cause the majority of nosocomial infections globally.


Asunto(s)
Técnicas de Tipificación Bacteriana/métodos , Enterococcus faecalis/clasificación , Enterococcus faecalis/genética , Enterococcus faecium/clasificación , Enterococcus faecium/genética , Polimorfismo de Nucleótido Simple , Alelos , Cartilla de ADN/genética , Humanos , Reacción en Cadena de la Polimerasa/métodos
14.
Thorax ; 64(11): 926-31, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19574243

RESUMEN

BACKGROUND: Pseudomonas aeruginosa is the most common bacterial pathogen in patients with cystic fibrosis (CF). Current infection control guidelines aim to prevent transmission via contact and respiratory droplet routes and do not consider the possibility of airborne transmission. It was hypothesised that subjects with CF produce viable respirable bacterial aerosols with coughing. METHODS: A cross-sectional study was undertaken of 15 children and 13 adults with CF, 26 chronically infected with P aeruginosa. A cough aerosol sampling system enabled fractioning of respiratory particles of different sizes and culture of viable Gram-negative non-fermentative bacteria. Cough aerosols were collected during 5 min of voluntary coughing and during a sputum induction procedure when tolerated. Standardised quantitative culture and genotyping techniques were used. RESULTS: P aeruginosa was isolated in cough aerosols of 25 subjects (89%), 22 of whom produced sputum samples. P aeruginosa from sputum and paired cough aerosols were indistinguishable by molecular typing. In four cases the same genotype was isolated from ambient room air. Approximately 70% of viable aerosols collected during voluntary coughing were of particles

Asunto(s)
Tos/microbiología , Fibrosis Quística/microbiología , Bacterias Gramnegativas/aislamiento & purificación , Infecciones por Bacterias Gramnegativas/microbiología , Adolescente , Adulto , Niño , Enfermedad Crónica , Estudios Transversales , Femenino , Volumen Espiratorio Forzado , Infecciones por Bacterias Gramnegativas/transmisión , Humanos , Exposición por Inhalación , Masculino , Persona de Mediana Edad , Esputo/microbiología , Adulto Joven
15.
J Appl Microbiol ; 106(5): 1438-47, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19191944

RESUMEN

AIMS: Influenza is commonly spread by infectious aerosols; however, detection of viruses in aerosols is not sensitive enough to confirm the characteristics of virus aerosols. The aim of this study was to develop an assay for respiratory viruses sufficiently sensitive to be used in epidemiological studies. METHOD: A two-step, nested real-time PCR assay was developed for MS2 bacteriophage, and for influenza A and B, parainfluenza 1 and human respiratory syncytial virus. Outer primer pairs were designed to nest each existing real-time PCR assay. The sensitivities of the nested real-time PCR assays were compared to those of existing real-time PCR assays. Both assays were applied in an aerosol study to compare their detection limits in air samples. CONCLUSIONS: The nested real-time PCR assays were found to be several logs more sensitive than the real-time PCR assays, with lower levels of virus detected at lower Ct values. The nested real-time PCR assay successfully detected MS2 in air samples, whereas the real-time assay did not. SIGNIFICANCE AND IMPACT OF THE STUDY: The sensitive assays for respiratory viruses will permit further research using air samples from naturally generated virus aerosols. This will inform current knowledge regarding the risks associated with the spread of viruses through aerosol transmission.


Asunto(s)
Microbiología del Aire , Reacción en Cadena de la Polimerasa/métodos , Virus/aislamiento & purificación , Aerosoles , Humanos , ARN Viral/aislamiento & purificación , Sensibilidad y Especificidad , Virus/genética
16.
J Aerosol Sci ; 40(2): 122-133, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32287373

RESUMEN

Size distributions of expiratory droplets expelled during coughing and speaking and the velocities of the expiration air jets of healthy volunteers were measured. Droplet size was measured using the interferometric Mie imaging (IMI) technique while the particle image velocimetry (PIV) technique was used for measuring air velocity. These techniques allowed measurements in close proximity to the mouth and avoided air sampling losses. The average expiration air velocity was 11.7 m/s for coughing and 3.9 m/s for speaking. Under the experimental setting, evaporation and condensation effects had negligible impact on the measured droplet size. The geometric mean diameter of droplets from coughing was 13.5 µm and it was 16.0 µm for speaking (counting 1-100). The estimated total number of droplets expelled ranged from 947 to 2085 per cough and 112-6720 for speaking. The estimated droplet concentrations for coughing ranged from 2.4 to 5.2 cm-3 per cough and 0.004-0.223 cm-3 for speaking.

17.
Artículo en Inglés | MEDLINE | ID: mdl-19070538

RESUMEN

Raman spectroscopic analyses of 1st century AD Romano-British villa wall-painting fragments from two important military and early urban centres at Colchester and Lincoln have demonstrated some interesting contrasts in technique and palette usage. Colchester, the earliest fortified settlement, developed a sophisticated painting and craft industry compared with Lincoln in the assimilation of novel substrate preparation ideas and pigment adoption. The earliest use of the rather rare purple mineral pigment, caput mortuum, hitherto reported in only a few Roman villas elsewhere in mainland Europe, is in evidence in this early phase settlement and the use of gypsum as a special ground preparation agent as an additive to the more common limewash putty to enhance the effect of the use of lazurite as a pigment is worthy of note in this context. Otherwise, the pigments are seen to be those that are quite normally encountered in Roman villas, namely, haematite, goethite, terre verte, and carbon. The results of this study indicate that at Colchester there was a continued development in technique into the colonial phase compared with a stagnation in Lincoln; these scientific results have created a stimulus for further historical research into pigment and techniques development for wall paintings at the fringe of the Roman Empire in the 1st-3rd Centuries AD.


Asunto(s)
Arqueología/métodos , Colorantes/análisis , Pinturas/historia , Espectrometría Raman/métodos , Historia Antigua , Minerales/análisis , Reino Unido
18.
Diabetologia ; 51(10): 1893-900, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18709353

RESUMEN

AIMS/HYPOTHESIS: The 5'-AMP-activated protein kinase (AMPK) pathway is intact in type 2 diabetic patients and is seen as a target for diabetes treatment. In this study, we aimed to assess the impact of the AMPK activator 5-aminoimidazole-4-carboxamide riboside (AICAR) on both glucose and fatty acid metabolism in vivo in type 2 diabetic patients. METHODS: Stable isotope methodology and blood and muscle biopsy sampling were applied to assess blood glucose and fatty acid kinetics following continuous i.v. infusion of AICAR (0.75 mg kg(-1) min(-1)) and/or NaCl (0.9%) in ten male type 2 diabetic patients (age 64 +/- 2 years; BMI 28 +/- 1 kg/m(2)). RESULTS: Plasma glucose rate of appearance (R (a)) was reduced following AICAR administration, while plasma glucose rate of disappearance (R (d)) was similar in the AICAR and control test. Consequently, blood glucose disposal (R (d) expressed as a percentage of R (a)) was increased following AICAR infusion (p < 0.001). Accordingly, a greater decline in plasma glucose concentration was observed following AICAR infusion (p < 0.001). Plasma NEFA R (a) and R (d) were both significantly reduced in response to AICAR infusion, and were accompanied by a significant decline in plasma NEFA concentration. Although AMPK phosphorylation in skeletal muscle was not increased, we observed a significant increase in acetyl-CoA carboxylase phosphorylation (p < 0.001). CONCLUSIONS/INTERPRETATION: The i.v. administration of AICAR reduces hepatic glucose output, thereby lowering blood glucose concentrations in vivo in type 2 diabetic patients. Furthermore, AICAR administration stimulates hepatic fatty acid oxidation and/or inhibits whole body lipolysis, thereby reducing plasma NEFA concentration.


Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Diabetes Mellitus Tipo 2/metabolismo , Glucosa/metabolismo , Hipoglucemiantes/farmacología , Hígado/efectos de los fármacos , Ribonucleótidos/farmacología , Aminoimidazol Carboxamida/farmacología , Aminoimidazol Carboxamida/uso terapéutico , Glucemia/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Inyecciones Intravenosas , Lipólisis/efectos de los fármacos , Hígado/metabolismo , Masculino , Persona de Mediana Edad , Ribonucleótidos/uso terapéutico , Resultado del Tratamiento
19.
Mar Pollut Bull ; 56(8): 1469-75, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18561957

RESUMEN

Biochemical fingerprinting (BF) databases of 524 enterococci and 571 Escherichia coli isolates and an antibiotic resistance analysis (ARA) database comprising of 380 E. coli isolates from four suspected sources (i.e. dogs, chickens, waterfowls, and human sewage) were developed to predict the sources of faecal pollution in a recreational coastal lake. Twenty water samples representing four sampling episodes were collected from five sites and the enterococci and E. coli population from each site were compared with those of the databases. The degree of similarity between bacterial populations was measured as population similarity (Sp) coefficient. Using the BF-database, bacterial populations of waterfowls showed the highest similarity with the water samples followed by a sewage treatment plant (STP). Higher population similarities were found between samples from STP and water samples especially at two sites (T2 and T3) which were located near the sewerage pipes collecting wastewater from the study area. When using the ARA-database, the highest similarity was found between E. coli populations from STP and water samples at sites T2 and T4. Both faecal indicators and as well as methods predicted human faecal pollution, possibly through leakage from submerged sewerage pipes. The results indicated that the Sp-analysis of faecal indicator bacterial populations from suspected sources and water samples can be used as a simple tool to predict the source(s) of faecal pollution in surface waters.


Asunto(s)
Monitoreo del Ambiente , Heces/microbiología , Agua de Mar/microbiología , Contaminantes del Agua/análisis , Recuento de Colonia Microbiana , Farmacorresistencia Bacteriana , Enterococcus/química , Enterococcus/aislamiento & purificación , Escherichia coli/química , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación
20.
Anal Chim Acta ; 588(1): 108-16, 2007 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-17386799

RESUMEN

In archaeometry, one of the main concerns is to extract information from an art object, without damaging it. Raman spectroscopy is being applied in this research field with recent developments in mobile instrumentation facilitating more routine analysis. This research paper evaluates the performances of five mobile Raman instruments (Renishaw RA100, Renishaw Portable Raman Analyser RX210, Ocean Optics RSL-1, Delta Nu Inspector Raman, Mobile Art Analyser--MArtA) in three different laboratories. A set of samples were collected, in order to obtain information on the spectral performances of the instruments including: spectral resolution, calibration, laser cut-off, the ability to record spectra of organic and inorganic pigments through varnish layers and on the possibilities to identify biomaterials. Spectra were recorded from predefined regions on a canvas painting to simulate the investigation of artworks and the capabilities to record spectra from hardly accessible areas was evaluated.


Asunto(s)
Arte , Espectrometría Raman/instrumentación , Espectrometría Raman/métodos , Arqueología/instrumentación , Arqueología/métodos , Técnicas de Laboratorio Clínico , Diseño de Equipo , Tecnología de Fibra Óptica , Proyectos de Investigación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...