22 resultados para G8630 1887 .B6

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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PURPOSE. A spontaneously arising retinal pigment epithelial (RPE) cell line (B6-RPE07) was cloned from a primary culture of mouse RPE cells and maintained in culture for more than 18 months. Morphologic and functional properties of this cell line have been characterized.

METHODS. The morphology of the B6-RPE07 cells was examined by phase-contrast light microscopy, electron microscopy, and confocal microscopy. Barrier properties were measured by the flux of fluorescence from the apical to the basolateral compartment of culture chambers. The abilities of the cells to bind/phagocytose photoreceptor outer segments (POS) were determined by confocal microscopy, electron microscopy, and flow cytometry. Cytokine/chemokine secretion was measured by cytometric bead array. The expression of visual cycle proteins was determined by RT-PCR and Western blotting.

RESULTS. In standard culture conditions, B6-RPE07 cells display cobblestone morphology. When cultured on three-dimensional (3D) collagen gel–coated membranes, B6-RPE07 cells exhibit a monolayer epithelial polarization with apical surface microvilli. Immunohistochemistry of B6-RPE07 cultures revealed a high expression of pan-cytokeratin. B6-RPE07 cells also expressed the retinal pigment epithelium-specific marker CRALBP, but not RPE65. Cell junction proteins ZO-1 and ß-catenin, but not claudin-1/3 or occludin-1, were observed in B6-RPE07 cells. B6-RPE07 cells are able to bind, phagocytose, and digest POS. Finally, B6-RPE07 cells produce high levels of IL-6 and CCL2.

CONCLUSIONS. This is the first report of a mouse RPE cell line with morphology, phenotype, and function similar to those of in vivo mouse RPE cells. This cell line will be a valuable resource for future RPE studies, in particular for in vivo gene modification and transplantation studies.

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This article deals with the encounters between a traditional Korean rural and island population and western military forces when the British navy occupied Geomundo, an archipelago known to them as Port Hamilton, for 22 months between 1885 and 1887. The paper first outlines the sometimes painful process of East Asian countries being opened up to trade and outside influences in the 19th century, a process sometimes urged upon them by naval weapons in this era of gunboat diplomacy. This provides the setting for the Port Hamilton Affair itself when in preparation for possible war with Russia, a British naval squadron steamed into Port Hamilton and took it without reference to the local people or their national government. After brief reference to the political consequences of this action, the focus is then on what the records from the occupation and earlier investigations by the British, who had long coveted the islands’ strategic harbour, reveal about the life of the islanders. The article considers both their traditional life, from a time rather before western travel accounts were written about the Korean mainland, and how the islanders fared under the British.

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BACKGROUND: Current data suggest that physiologic doses of vitamin B-6 have no significant homocysteine-lowering effect. It is possible that an effect of vitamin B-6 was missed in previous trials because of a much greater effect of folic acid, vitamin B-12, or both. OBJECTIVE: The aim of this study was to investigate the effect of low-dose vitamin B-6 supplementation on fasting total homocysteine (tHcy) concentrations in healthy elderly persons who were made replete with folate and riboflavin. DESIGN: Twenty-two healthy elderly persons aged 63-80 y were supplemented with a low dose of vitamin B-6 (1.6 mg/d) for 12 wk in a randomized, double-blind, placebo-controlled trial after repletion with folic acid (400 microg/d for 6 wk) and riboflavin (1.6 mg/d for 18 wk); none of the subjects had a vitamin B-12 deficiency. RESULTS: Folic acid supplementation lowered fasting tHcy by 19.6% (P

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Computational modelling is becoming ever more important for obtaining regulatory approval for new medical devices. An accepted approach is to infer performance in a population from an analysis conducted for an idealised or ‘average’ patient; we present here a method for predicting the performance of an orthopaedic implant when released into a population—effectively simulating a clinical trial. Specifically we hypothesise that an analysis based on a method for predicting the performance in a population will lead to different conclusions than an analysis based on an idealised or ‘average’ patient. To test this hypothesis we use a finite element model of an intramedullary implant in a bone whose size and remodelling activity is different for each individual in the population. We compare the performance of a low Young’s modulus implant (View the MathML source) to one with a higher Young’s modulus (200 GPa). Cyclic loading is applied and failure is assumed when the migration of the implant relative to the bone exceeds a threshold magnitude. The analysis for an idealised of ‘average’ patient predicts that the lower modulus device survives longer whereas the analysis simulating a clinical trial predicts no statistically-significant tendency (p=0.77) for the low modulus device to perform better. It is concluded that population-based simulations of implant performance–simulating a clinical trial–present a very valuable opportunity for more realistic computational pre-clinical testing of medical devices.

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Higher heating value (HHV) is probably the most important property of the fuels. Bomb calorimeter and derived empirical formulae are often used for accurate determination of HHV of fuels. A useful empirical equation was derived to estimate HHV of petro-diesels from their C and H contents: HHV (in MJ/kg) = 0.3482(C) + 1.1887(H), r (2) = 0.9956. The derived correlation was validated against the most common formulae in the literature, Boie and Channiwala-Parikh correlations. Accordingly, accurate determination of C and H contents is essential for estimation of HHV and avoids using a bomb calorimeter. However, accurate estimation of C and H contents requires using expensive and laborious gas chromatographic techniques. In this work, chemometry offered a simple method for HHV determination of petro-diesels without using bomb calorimeter or even gas chromatography. PLS-1 calibration was used instead of gas chromatography to find C and H contents from the non-selective mid-infrared (MIR) spectra of petro-diesels, HHV was then estimated from the earlier empirical equation. The proposed method predicts HHV of petro-diesels with high accuracy and precision, with modest analysis costs. The present method may be extended to other fuels.

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Background
Restorative justice is “a process whereby parties with a stake in a specific offence resolve collectively how to deal with the aftermath of the offence and its implications for the future” (Marshall 2003). Despite the increasing use of restorative justice programmes as an alternative to court proceedings, no systematic review has been undertaken of the available evidence on the effectiveness of these programmes with young offenders. Recidivism in young offenders is a particularly worrying problem, as recent surveys have indicated
the frequency of re-offences for young offenders has ranged from 40.2% in 2000 to 37.8% in 2007 (Ministry of Justice 2009)

Objectives
To evaluate the effects of restorative justice conferencing programmes for reducing recidivism in young offenders.

Search methods
We searched the following databases up to May 2012: CENTRAL, 2012 Issue 5, MEDLINE (1978 to current), Bibliography of Nordic Criminology (1999 to current), Index to Theses (1716 to current), PsycINFO (1887 to current), Social Sciences Citation Index (1970 to current), Sociological Abstracts (1952 to current), Social Care Online (1985 to current), Restorative Justice Online (1975 to current), Scopus (1823 to current), Science Direct (1823 to current), LILACS (1982 to current), ERIC (1966 to current), Restorative Justice Online (4May 2012),WorldCat (9May 2012), ClinicalTrials.gov (19May 2012) and ICTRP (19May 2012). ASSIA,National Criminal Justice Reference Service and Social Services Abstracts were searched up to May 2011. Relevant bibliographies, conference programmes and journals were also searched.

Selection criteria
Randomised controlled trials (RCTs) or quasi-RCTs of restorative justice conferencing versus management as usual, in young offenders.

Data collection and analysis
Two authors independently assessed the risk of bias of included trials and extracted the data. Where necessary, original investigators were contacted to obtain missing information.

Main results
Four trials including a total of 1447 young offenders were included in the review. Results failed to find a significant effect for restorative justice conferencing over normal court procedures for any of the main analyses, including number re-arrested (odds ratio (OR) 1.00, 95% confidence interval (CI) 0.59 to 1.71; P = 0.99), monthly rate of reoffending (standardised mean difference (SMD) -0.06, 95% CI -0.28 to 0.16; P = 0.61), young person’s remorse following conference (OR 1.73, 95% CI 0.97 to 3.10; P = 0.06), young person’s recognition of wrongdoing following conference (OR 1.97, 95% CI 0.81 to 4.80; P = 0.14), young person’s self-perception following conference (OR 0.95, 95% CI 0.55 to 1.63; P = 0.85), young person’s satisfaction following conference (OR 0.42, 95% CI 0.04 to 4.07; P = 0.45) and victim’s satisfaction following conference (OR 4.05, 95%CI 0.56 to 29.04; P = 0.16). A small number of sensitivity analyses did indicate significant effects, although all are to be interpreted with caution.

Authors’ conclusions
There is currently a lack of high quality evidence regarding the effectiveness of restorative justice conferencing for young offenders. Caution is urged in interpreting the results of this review considering the small number of included studies, subsequent low power and high risk of bias. The effects may potentially be more evident for victims than offenders. The need for further research in this area is highlighted.

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Background: Despite differences in how it is defined, there is a general consensus amongst clinicians and researchers that the sexual abuse of children and adolescents (’child sexual abuse’) is a substantial social problem worldwide. The effects of sexual abuse manifest in a wide range of symptoms, including fear, anxiety, post-traumatic stress disorder and various externalising and internalising behaviour problems, such as inappropriate sexual behaviours. Child sexual abuse is associated with increased risk of psychological problems in adulthood. Cognitive-behavioural approaches are used to help children and their non-offending or ’safe’ parent tomanage the sequelae of childhood sexual abuse. This review updates the first Cochrane review of cognitive-behavioural approaches interventions for children who have been sexually abused, which was first published in 2006.

Objectives: To assess the efficacy of cognitive-behavioural approaches (CBT) in addressing the immediate and longer-term sequelae of sexual abuse on children and young people up to 18 years of age.

Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2011 Issue 4); MEDLINE (1950 to November Week
3 2011); EMBASE (1980 to Week 47 2011); CINAHL (1937 to 2 December 2011); PsycINFO (1887 to November Week 5 2011); LILACS (1982 to 2 December 2011) and OpenGrey, previously OpenSIGLE (1980 to 2 December 2011). For this update we also searched ClinicalTrials.gov and the International Clinical Trials Registry Platform (ICTRP).

Selection criteria: We included randomised or quasi-randomised controlled trials of CBT used with children and adolescents up to age 18 years who had experienced being sexually abused, compared with treatment as usual, with or without placebo control.

Data collection and analysis: At least two review authors independently assessed the eligibility of titles and abstracts identified in the search. Two review authors independently extracted data from included studies and entered these into Review Manager 5 software. We synthesised and presented data in both written and graphical form (forest plots).

Main results: We included 10 trials, involving 847 participants. All studies examined CBT programmes provided to children or children and a nonoffending parent. Control groups included wait list controls (n = 1) or treatment as usual (n = 9). Treatment as usual was, for the most part, supportive, unstructured psychotherapy. Generally the reporting of studies was poor. Only four studies were judged ’low risk of bias’ with regards to sequence generation and only one study was judged ’low risk of bias’ in relation to allocation concealment. All studies were judged ’high risk of bias’ in relation to the blinding of outcome assessors or personnel; most studies did not report on these, or other issues of bias. Most studies reported results for study completers rather than for those recruited.

Depression, post-traumatic stress disorder (PTSD), anxiety and child behaviour problems were the primary outcomes. Data suggest that CBT may have a positive impact on the sequelae of child sexual abuse, but most results were not statistically significant. Strongest evidence for positive effects of CBT appears to be in reducing PTSD and anxiety symptoms, but even in these areas effects tend to be 'moderate’ at best. Meta-analysis of data from five studies suggested an average decrease of 1.9 points on the Child Depression Inventory immediately after intervention (95% confidence interval (CI) decrease of 4.0 to increase of 0.4; I2 = 53%; P value for heterogeneity = 0.08), representing a small to moderate effect size. Data from six studies yielded an average decrease of 0.44 standard deviations on a variety of child post-traumatic stress disorder scales (95% CI 0.16 to 0.73; I2 = 46%; P value for heterogeneity = 0.10). Combined data from five studies yielded an average decrease of 0.23 standard deviations on various child anxiety scales (95% CI 0.3 to 0.4; I2=0%; P value for heterogeneity = 0.84). No study reported adverse effects.

Authors’ conclusions: The conclusions of this updated review remain the same as those when it was first published. The review confirms the potential of CBT to address the adverse consequences of child sexual abuse, but highlights the limitations of the evidence base and the need for more carefully conducted and better reported trials.

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Folate and vitamin B-6 act in generating methyl groups for homocysteine remethylation, but the kinetic effects of folate or vitamin B-6 deficiency are not known. We used an intravenous primed, constant infusion of stable isotope-labeled serine, methionine, and leucine to investigate one-carbon metabolism in healthy control (n = 5), folate-deficient (n = 4), and vitamin B-6-deficient (n = 5) human subjects. The plasma homocysteine concentration in folate-deficient subjects [15.9 +/-2.1 (SD) mu mol/l] was approximately two times that of control (7.4 +/-1.7 mmol/l) and vitamin B-6-deficient (7.7 +/-2.1 mmol/l) subjects. The rate of methionine synthesis by homocysteine remethylation was depressed (P = 0.027) in folate deficiency but not in vitamin B-6 deficiency. For all subjects, the homocysteine remethylation rate was not significantly associated with plasma homocysteine concentration (r = -0.44, P = 0.12). The fractional synthesis rate of homocysteine from methionine was positively correlated with plasma homocysteine concentration (r = 0.60, P = 0.031), and a model incorporating both homocysteine remethylation and synthesis rates closely predicted plasma homocysteine levels (r = 0.85, P = 0.0015). Rates of homocysteine remethylation and serine synthesis were inversely correlated (r = -0.89, P < 0.001). These studies demonstrate distinctly different metabolic consequences of vitamin B-6 and folate deficiencies.

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Vitamin B-6 deficiency causes mild elevation in plasma homocysteine, but the mechanism has not been clearly established. Serine is a substrate in one-carbon metabolism and in the transsulfuration pathway of homocysteine catabolism, and pyridoxal phosphate (PLP) plays a key role as coenzyme for serine hydroxymethyltransferase (SHMT) and enzymes of transsulfuration. In this study we used [H-2(3)]serine as a primary tracer to examine the remethylation pathway in adequately nourished and vitamin B-6-deficient rats pi and 0.1 mg pyridoxine (PN)/kg diet]. [H-2(3)]Leucine and [1-C-13]methionine were also used to examine turnover of protein and methionine pools, respectively, All tracers were injected intraperitoneally as a bolus dose, and then rats were killed (n = 4/time point) after 30, 60 and 120 min. Rats fed the low-PN diet had significantly lower growth and plasma and liver PLP concentrations, reduced liver SHMT activity, greater plasma and liver total homocysteine concentration, and reduced liver S-adenosylmethionine concentration. Hepatic and whole body protein turnover were reduced in vitamin B-6-deficient rats as evidenced by greater isotopic enrichment of [H-2(3)]leucine. Hepatic [H-2(2)]methionine production from [H-2(3)]serine via cytosolic SHMT and the remethylation pathway was reduced by 80.6% in vitamin B-6 deficiency. The deficiency did not significantly reduce hepatic cystathionine-beta-synthase activity, and in vivo hepatic transsulfuration flux shown by production of [H-2(3)]cysteine from the [H-2(3)]serine increased over twofold. In contrast, plasma appearance of [H-2(3)]cysteine was decreased by 89% in vitamin B-6 deficiency. The rate of hepatic homocysteine production shown by the ratio of [1-C-13]homocysteine/[1-C-13]methionine areas under enrichment vs. time curves was not affected by vitamin B-6 deficiency. Overall, these results indicate that vitamin B-6 deficiency substantially affects one-carbon metabolism by impairing both methyl group production for homocysteine remethylation and flux through whole-body transsulfuration.

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Mild hyperhomocysteinaemia is a major risk factor for vascular disease and neural tube defects (NTDs), conferring an approximately three-fold relative risk for each condition. It has several possible causes: heterozygosity for rare loss of function mutations in the genes for 5,10-methylene tetrahydrofolate reductase (MTHFR) or cystathionine-beta-synthase (CBS); dietary insufficiency of vitamin co-factors B6, B12 or folates; or homozygosity for a common 'thermolabile' mutation in the MTHFR gene which has also been associated with vascular disease and NTDs. We quantified the contribution of the thermolabile mutation to the hyperhomocysteinaemic phenotype in a working male population (625 individuals). Serum folate and vitamin B12 concentrations were also measured and their relationship with homocysteine status and MTHFR genotype assessed. The homozygous thermolabile genotype occurred in 48.4, 35.5, and 23.4% of the top 5, 10, and 20% of individuals (respectively) ranked by plasma homocysteine levels, compared with a frequency of 11.5% in the study population as a whole, establishing that the mutation is a major determinant of homocysteine levels at the upper end of the range. Serum folate concentrations also varied with genotype, being lowest in thermolabile homozygotes. The MTHFR thermolabile genotype should be considered when population studies are designed to determine the effective homocysteine-lowering dose of dietary folate supplements, and when prophylactic doses of folate are recommended for individuals.