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1.
J Clin Med ; 13(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38337380

RESUMEN

Background: Chronic conditions, especially pain conditions, have a very significant impact on quality of life and on workplaces. Workplace interventions for chronic conditions are heterogenous, multidimensional, and sometimes poorly evidenced. The Joint Action for Chronic Disease Plus (CHRODIS Plus), including The CHRODIS Plus Workbox on Employment and Chronic Conditions (CPWEC), aimed to combat this, prevent chronic disease and multimorbidity, and influence policy in Europe. However, the supporting evidence behind CHRODIS Plus has not been formally assessed. Methods: A scoping review was carried out; Embase, MEDLINE, and CINAHL were searched for literature related to CHRODIS Plus and pain. Title and abstract and full-text screening were carried out in duplicate and independently. Additionally, CHRODIS Plus authors were approached for unpublished data. Secondly, the search was broadened to CHRODIS Plus and pain-causing conditions. Grey literature was also searched. Appropriateness appraisal was derived from the Trial Forge Guidance. Systematic reviews, on which CPWEC was based, were appraised using the A Measurement Tool to Assess systematic Reviews (AMSTAR) 2 tool. Results: The initial search yielded two results, of which zero were suitable to be included in the scoping review. The second, broader search revealed 14 results; however, none were deemed suitable for inclusion. AMSTAR 2 scores revealed that the three systematic reviews influencing CPWEC were of varying quality (from critically low to moderate). Conclusions: CPWEC is based on heterogenous reviews of varying quality. However, comparable tools are designed using alternative forms of evidence. Further research evaluating the post-implementation efficacy of the tool is needed.

2.
J Clin Med ; 10(18)2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34575272

RESUMEN

BACKGROUND: Colorectal cancer (CRC) is a leading cause of mortality worldwide and in the UK. Surgical resection is the main curative treatment modality available and using a laparoscopic vs. an open approach may have a direct influence on the inflammatory response, influencing cancer biology and potentially the recurrence kinetics by promoting cancer growth. METHODS: This systematic review aims to compare laparoscopic with open surgery for the treatment of colon cancer with a specific focus on the moment of the recurrence. We included randomised controlled trials in intended curative surgery for colon cancer in adults. INTERVENTIONS: Studies investigating laparoscopic vs. open resection as an intended curative treatment for patients with confirmed carcinoma of the colon. The two co-primary outcomes were the time to recurrence and the overall survival (OS) and disease-free survival (DFS) at three and five years. Meta-analyses were done on the mean differences. RESULTS: After selection, we reviewed ten randomised controlled trials. Most of the trials did not display a statistically significant difference in either DFS or OS at three or at five years when comparing laparoscopic to open surgery. Groups did not differ for the OS and DFS, especially regarding the time needed to observe the median recurrence rate. The quality of evidence (GRADE) was moderate to very low. CONCLUSION: We observed no difference in the recurrence kinetics, OS or DFS at three or five years when comparing laparoscopic to open surgery in colon cancer.

3.
Brain Inj ; 30(10): 1213-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27466692

RESUMEN

BACKGROUND AND PURPOSE: Effects of high-intensity exercise on endurance, mobility and gait speed of adults with chronic moderate-to-severe acquired brain injury (ABI) were investigated. It was hypothesized that intensive exercise would be associated with improvements in impairment and activity limitation measures. PARTICIPANTS: Fourteen adults with chronic ABI in supported independent living who could stand with minimal or no assist and walk with or without ambulation device were studied. Eight presented with low ambulatory status. METHODS: This was a single group pre- and post-intervention study. Participants received a 6-week exercise intervention for 60-90 minutes, 3 days/week assisted by personal trainers under physical therapist supervision. Measures (6MWT, HiMAT and 10MWT) were collected at baseline, post-intervention and 6 weeks later. Repeated measures T-test and Wilcoxon Signed Ranks test were used. RESULTS: Post-intervention improvements were achieved on average on all three measures, greater than minimal detectable change (MDC) for this population. Three participants transitioned from low-to-high ambulatory status and maintained the change 6 weeks later. DISCUSSION AND CONCLUSION: People with chronic ABI can improve endurance, demonstrate the ability to do advanced gait and improve ambulatory status with 6 weeks of intensive exercise. Challenges to sustainability of exercise programmes for this population remain.


Asunto(s)
Lesión Encefálica Crónica/complicaciones , Terapia por Ejercicio/métodos , Trastornos Neurológicos de la Marcha/etiología , Trastornos Neurológicos de la Marcha/rehabilitación , Velocidad al Caminar/fisiología , Adulto , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Resistencia Física/fisiología , Proyectos Piloto , Estadísticas no Paramétricas
4.
PeerJ ; 3: e943, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26020003

RESUMEN

Transporter-facilitated arsenite extrusion is the major pathway of arsenic resistance within bacteria. So far only two types of membrane-bound transporter proteins, ArsB and ArsY (ACR3), have been well studied, although the arsenic transporters in bacteria display considerable diversity. Utilizing accumulated genome sequence data, we searched arsenic resistance (ars) operons in about 2,500 bacterial strains and located over 700 membrane-bound transporters which are encoded in these operons. Sequence analysis revealed at least five distinct transporter families, with ArsY being the most dominant, followed by ArsB, ArsP (a recently reported permease family), Major Facilitator protein Superfamily (MFS) and Major Intrinsic Protein (MIP). In addition, other types of transporters encoded in the ars operons were found, but in much lower frequencies. The diversity and evolutionary relationships of these transporters with regard to arsenic resistance will be discussed.

5.
Bioresour Technol ; 167: 521-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25016367

RESUMEN

Multi-wavelength chlorophyll fluorescence analysis was utilised to examine the photosynthetic efficiency of the biofuel-producing alga Nannochloropsis oculata, grown under two light regimes; low (LL) and high (HL) irradiance levels. Wavelength dependency was evident in the functional absorption cross-section of Photosystem II (σII(λ)), absolute electron transfer rates (ETR(II)), and non-photochemical quenching (NPQ) of chlorophyll fluorescence in both HL and LL cells. While σII(λ) was not significantly different between the two growth conditions, HL cells upregulated ETR(II) 1.6-1.8-fold compared to LL cells, most significantly in the wavelength range of 440-540 nm. This indicates preferential utilisation of blue-green light, a highly relevant spectral region for visible light in algal pond conditions. Under these conditions, the HL cells accumulated saturated fatty acids, whereas polyunsaturated fatty acids were more abundant in LL cells. This knowledge is of importance for the use of N. oculata for fatty acid production in the biofuel industry.


Asunto(s)
Aclimatación , Clorofila/metabolismo , Microalgas/metabolismo , Fotosíntesis , Absorción Fisicoquímica , Transporte de Electrón , Ésteres/análisis , Ácidos Grasos/análisis , Fluorescencia , Complejo de Proteína del Fotosistema II/metabolismo , Teoría Cuántica
6.
PLoS One ; 9(1): e86047, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24465862

RESUMEN

A matrix of photobioreactors integrated with metabolic sensors was used to examine the combined impact of light and temperature variations on the growth and physiology of the biofuel candidate microalgal species Nannochloropsis oculata. The experiments were performed with algal cultures maintained at a constant 20 °C versus a 15 °C to 25 °C diel temperature cycle, where light intensity also followed a diel cycle with a maximum irradiance of 1920 µmol photons m(-2) s(-1). No differences in algal growth (Chlorophyll a) were found between the two environmental regimes; however, the metabolic processes responded differently throughout the day to the change in environmental conditions. The variable temperature treatment resulted in greater damage to photosystem II due to the combined effect of strong light and high temperature. Cellular functions responded differently to conditions before midday as opposed to the afternoon, leading to strong hysteresis in dissolved oxygen concentration, quantum yield of photosystem II and net photosynthesis. Overnight metabolism performed differently, probably as a result of the temperature impact on respiration. Our photobioreactor matrix has produced novel insights into the physiological response of Nannochloropsis oculata to simulated environmental conditions. This information can be used to predict the effectiveness of deploying Nannochloropsis oculata in similar field conditions for commercial biofuel production.


Asunto(s)
Microalgas/crecimiento & desarrollo , Fotobiorreactores/microbiología , Biocombustibles/microbiología , Clorofila/metabolismo , Clorofila A , Diseño de Equipo , Luz , Microalgas/fisiología , Fotoperiodo , Fotosíntesis , Temperatura
7.
Plant Cell Environ ; 33(6): 995-1004, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20102538

RESUMEN

The dinoflagellate alga Symbiodinium sp., living in symbiosis with corals, clams and other invertebrates, is a primary producer in coral reefs and other marine ecosystems. The function of the carbon-fixing enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) in dinoflagellates is difficult to study because its activity is rapidly lost after extraction from the cell. We report procedures for the extraction of Rubisco from Symbiodinium cells and for stable storage. We describe a continuous assay for Rubisco activity in these crude cell extracts using the Mn(2+) chemiluminescence of Rubisco oxygenase. Chemiluminescence time courses exhibited initial transients resembling bacterial Form II Rubisco, followed by several minutes of linearly decreasing activity. The initial activity was determined from extrapolation of this linear section of the time course. The activity of fast-frozen cell extracts was stable at -80 degrees C and, after thawing and storage on ice, remained stable for up to 1 h before declining non-linearly. Crude cell extracts bound [(14)C] 2-carboxy-D-arabitinol 1,5-bisphosphate to a high molecular mass fraction separable by gel filtration chromatography. After pre-treatment of Symbiodinium cell cultures in darkness at temperatures above 30 degrees C, the extracted Rubisco activities decreased, with almost complete loss of activity above 36 degrees C. The implications for the sensitivity to elevated temperature of Symbiodinium photosynthesis are assessed.


Asunto(s)
Dinoflagelados/enzimología , Mediciones Luminiscentes/métodos , Manganeso/metabolismo , Ribulosa-Bifosfato Carboxilasa/metabolismo , Estrés Fisiológico , Temperatura , Dominio Catalítico , Extractos Celulares , Células Cultivadas , Activación Enzimática , Factores de Tiempo
8.
J Biol Chem ; 278(19): 16488-93, 2003 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-12604603

RESUMEN

Chemiluminescence emitted by Mn(2+)-activated ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisco) while catalyzing oxygenation was analyzed to clarify the source of the emission. Using dual detectors capturing radiation over a wide range of visible and infrared wavelengths, we tested for radiation from singlet O(2) decay and found it to be essentially absent (less than 0.1% of the total luminescence intensity). Spectra were determined between 647 and 885 nm with a very sensitive, charge-coupled detector-based spectrograph to detect differences in the emission spectra between rubiscos from bacterial and higher plant sources. All Mn(2+)-activated rubiscos emitted a broad, smooth spectrum of chemiluminescence, unchanging as the reaction progressed. The spectra from higher plant rubiscos (spinach and both the wild type and an L335V mutant from tobacco), all exhibited maxima at about 800 nm. However, Mn(2+)-activated rubisco from the bacterium, Rhodospirillum rubrum, emitted at shorter wavelengths (760 nm peak), demonstrating host ligand-field influences arising from aminoacyl residue differences and/or conformational changes caused by the absence of small subunits. The findings provide strong evidence that the chemiluminescence arises from an excited state of the active-site Mn(2+) that is produced during oxygenation. We propose that the Mn(2+) becomes excited by a one-electron exchange mechanism of oxygenation that is not available to Mg(2+)-activated rubisco.


Asunto(s)
Proteínas de Plantas/química , Plantas/enzimología , Ribulosa-Bifosfato Carboxilasa/química , Activación Enzimática , Mediciones Luminiscentes , Magnesio/química , Magnesio/metabolismo , Proteínas de Plantas/metabolismo , Ribulosa-Bifosfato Carboxilasa/metabolismo
9.
Funct Plant Biol ; 29(1): 73-80, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32689453

RESUMEN

Compared with microorganisms and mammalian tissues, information is scant on the enzymes responsible for arsenic metabolism in plants. This study investigated the arsenic methylation activities extractable from leaves and roots of Agrostis tenuis Sibth. plants grown in complete nutrient media and exposed to arsenate (135-538 M) for 3 d before harvesting. Methylation activity was determined in leaf and root extracts using an in vitro assay based onS-[3H-methyl]adenosyl-L-methionine (3H-SAM) with either arsenite or arsenate as substrate. Arsenite methylation activity was low in leaf extracts from plants not exposed to arsenate, but was greatly enhanced after acute exposure, with the induced methylation activity greatest in extracts from plants exposed to 269 M arsenate. Monomethylarsonate (MMA) was the predominant early product, but over longer assay times dimethylarsinate (DMA) accumulated at the rate of 660 amol mg protein-1 min-1 to levels exceeding MMA. With arsenate as substrate, methylation activity was much lower than with arsenite, implying that arsenite is the preferred substrate for methylation. Root extract assays exhibited no DMA, however small amounts of MMA were formed with arsenite as substrate. In contrast to leaves, the methylation activity did not increase in root extracts from plants exposed to arsenate. These findings suggest that arsenate in the plant growth medium was taken up by the roots and converted to arsenite before methylation proceeded in the leaves, accompanied by induction of arsenic methyltransferase activities.

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