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J Kirby

Publications and source records attributed to J Kirby.

At least 19 recordsLinked to original sources
PubMed2006

Clinical features of hereditary spastic paraplegia due to spastin mutation.

BACKGROUND: Mutations in the spastin gene are the commonest cause of hereditary spastic paraparesis (HSP), accounting for up to 40% of autosomal dominant cases. The phenotype associated with HSP due to mutation in the spastin gene (SPG4) tends to be pure HSP. OBJECTIVE: To characterize in more detail the genetic and phenotypic characteristics of SPG4 by examining a large cohort of patients with HSP. METHODS: The authors identified patients who tested positive for spastin mutation using a direct sequencing approach of all exons. RESULTS: The authors identified spastin mutations in 53 patients. Twenty-seven of the mutations identified were novel. The phenotype in the majority of patients was of pure HSP. In one individual, a complicated phenotype with progressive bulbar dysfunction and respiratory insufficiency was observed. Evidence of lower motor neuron dysfunction in a subgroup of SPG4 patients was identified. The missense changes S44L and P45Q were identified in patients with other spastin mutations and seemed to be exerting a phenotype-modifying effect. CONCLUSION: These findings add to the number of spastin mutations identified and demonstrate the importance of screening the whole gene, given the possibility of double mutations and intragenic modifiers. The identification of the complicated phenotypes has important implications for identifying the phenotype of patients in whom spastin screening should be considered. The presence of lower motor neuron dysfunction in a subgroup of SPG4 patients suggests that the cellular dysfunction in SPG4 extends beyond the axonal projections of upper motor neurons and ascending sensory pathways.

Adenosine Triphosphatases↗
PubMed2006

A systematic review of the clinical effectiveness of donepezil, rivastigmine and galantamine on cognition, quality of life and adverse events in Alzheimer's disease.

BACKGROUND: The use of cholinesterase inhibitors for Alzheimer's disease (AD) is currently being appraised by the National Institute for Clinical Evidence (NICE). This article provides the latest evidence that NICE will be using as part of this appraisal process. OBJECTIVE: To provide a systematic review of the best quality evidence of the effects of donepezil, rivastigmine and galantamine on cognition, quality of life and adverse events in people with mild to moderately-severe AD. DESIGN: Electronic databases were searched, references of all retrieved articles were checked, and experts were contacted for advice, peer review and to identify additional references. Randomised controlled trials (RCTs) were included if they fulfilled pre-specified criteria. Data were synthesised through a narrative review. RESULTS: Twenty-six RCTs that compared any one of the cholinesterase inhibitors with either a control group or with another cholinesterase inhibitor were included. The quality of reporting and methodology was varied. Treatment with donepezil, rivastigmine or galantamine resulted in significantly better cognitive performance using the ADAS-cog scale when compared with placebo. These findings were generally supported using the MMSE scale. Results from head to head comparisons were limited by the low number of studies and the study quality; generally showing no robust support for any one drug. Few studies evaluated quality of life. Adverse events were generally related to the gastrointestinal system, with a tendency for these to be more common in the treatment arms. CONCLUSIONS: The cholinesterase inhibitors donepezil, rivastigmine, and galantamine can delay cognitive impairment in patients with mild to moderately-severe AD for at least 6 months duration.

Alzheimer Disease↗
PubMed2006

The clinical and cost-effectiveness of donepezil, rivastigmine, galantamine and memantine for Alzheimer's disease.

OBJECTIVES: To provide an update review of the best quality evidence for the clinical effectiveness and cost-effectiveness of donepezil, rivastigmine and galantamine for mild to moderately severe Alzheimer's disease (AD) and of memantine for moderately severe to severe AD. DATA SOURCES: Electronic databases, experts in the field and manufacturer submissions to the National Institute for Health and Clinical Excellence (NICE). REVIEW METHODS: A systematic review of the literature and an economic evaluation were undertaken. The quality of included randomised controlled trials (RCTs) was assessed using criteria developed by the NHS Centre for Reviews and Dissemination. An outline assessment of economic evaluations was undertaken using a standard checklist. The clinical and cost-effectiveness data were synthesised through a narrative review with full tabulation of the results of included studies. Where appropriate, meta-analysis of data was undertaken. RESULTS: For mild to moderately severe AD, the results of the study suggested that all three treatments were beneficial when assessed using cognitive outcome measures. Global outcome measures were positive for donepezil and rivastigmine, but mixed for galantamine. Results for measures of function were mixed for donepezil and rivastigmine, but positive for galantamine. Behaviour and mood measures were mixed for donepezil and galantamine, but showed no benefit for rivastigmine. For memantine, two published RCTs were included; in one of these trials the participants were already being treated with donepezil. The results suggest that memantine is beneficial when assessed using functional and global measurements. The effect of memantine on cognitive and behaviour and mood outcomes is, however, less clear. Literature on the cost-effectiveness of donepezil, rivastigmine and galantamine was dominated by industry-sponsored studies, and studies varied in methods and results. Of the three UK studies, two report donepezil as not cost-effective, whereas a third study reports an additional cost (1996 pounds sterling) of between 1200 pounds sterling and 7000 pounds sterling per year in a non-severe AD health state (concerns over these estimates are raised, suggesting that they may underestimate the true cost-effectiveness of donepezil). Cost-effectiveness analysis undertaken in this review suggests that donepezil treatment has a cost per quality-adjusted life-year (QALY) in excess of 80,000 pounds sterling, with donepezil treatment reducing the mean time spent in full-time care (delays progression of AD) by 1.42-1.59 months (over a 5-year period). From four published cost-effectiveness studies, two UK studies report additional costs associated with rivastigmine treatment. Cost-effectiveness analysis undertaken in the current review suggests that rivastigmine treatment has a cost per QALY in excess of 57,000 pounds sterling, with rivastigmine treatment reducing the mean time spent in full-time care (delays progression) by 1.43-1.63 months (over a 5-year period). From five published cost-effectiveness studies, one UK study reports a cost per QALY of 8693 pounds sterling for 16-mg galantamine treatment and 10,051 pounds sterling for 24-mg galantamine treatment (concerns raised suggest that this may underestimate the true cost-effectiveness of galantamine). Cost-effectiveness analysis undertaken in the present review suggests that galantamine treatment has a cost per QALY in excess of 68,000 pounds sterling, with galantamine reducing the time spent in full-time care (delays progression) by 1.42-1.73 months (over a 5-year period). From two published cost-effectiveness studies, one reports analysis for the UK, finding that memantine treatment results in cost savings and benefits in terms of delaying disease progression (concerns raised suggest that this may underestimate the true cost-effectiveness of memantine). In the current review, the cost-effectiveness of memantine has not been modelled separately, but where alternative parameter inputs on the cost structure and utility values have been used in a reanalysis using the industry model, the cost-effectiveness is reported at between 37,000 pounds sterling and 52,000 pounds sterling per QALY, with this alternative analysis still based on what is regarded as an optimistic or favourable effectiveness profile for memantine. CONCLUSIONS: Although results from the clinical effectiveness review suggest that these treatments may be beneficial, a number of issues need to be considered when assessing the results of the present review, such as the characteristics of the participants included in the individual trials, the outcome measures used, the length of study duration, the effects of attrition and the relationship between statistical significance and clinical significance. Many included trials were sponsored by industry. For donepezil, rivastigmine and galantamine, the cost savings associated with reducing the mean time spent in full-time care do not offset the cost of treatment sufficiently to bring estimated cost-effectiveness to levels generally considered acceptable by NHS policy makers. It is difficult to draw conclusions on the cost-effectiveness of memantine; it is suggested that further amendments to the potentially optimistic industry model (measure of effect) would offer higher cost per QALY estimates. Future research should include: information on the quality of the outcome measures used; development of quality of life instruments for patients and carers; studies assessing the effects of these interventions of durations longer than 12 months; comparisons of benefits between interventions; and research on the prediction of disease progression.

Aged↗
PubMed2005

Arsenic occurrence and species in near-shore macroalgae-feeding marine animals.

This study was undertaken to improve the understanding of arsenic species and their pathways of formation in marine animals: fish (Odax cyanomelas), abalone (Haliotis rubra), and sea urchins (Heliocidaris erythrogramma and Centrostephanus rodgersii) that are directly exposed through their diets to dimethyl arsenoriboses in macroalgae (Phyllospora comosa and Halopteris platycena). The identification of dimethyl arsenoriboses (phosphate, sulfonate, and glycerol) in both dominant macroalgae species, and especially digestive tissues of marine animals that consume them, suggests these arsenic species, are to some degree accumulated directly from their diets without degradation or conversion. An unknown arsenic species in H. rubra intestinal tissue was identified using tandem mass spectrometry as 2',3'-dihydroxypropyl 5-deoxy-5-trimethyl arsonioriboside (trimethyl glycerol arsenoribose). The concentration of trimethyl glycerol arsenoribose in H. rubra intestinal tissue was estimated to account for 28% (5.0 microg g(-1) dry mass) of the methanol-water-soluble arsenic fraction. The presence of a trimethyl glycerol arsenoribose in marine animal tissues may be due to microbial-mediated processes that promote the reduction and methylation of dimethyl arsenoriboses released during the breakdown of macroalgae in their diets. Arsenobetaine formation may then occur in the lumen of the digestive tract (i.e., mediated by microorganisms) or in the liver catalyzed by enzymes. The identification of a large amount of trimethyl glycerol arsenoribose in H. rubra intestinal tissue suggests this species is a main constituent in the pathway for arsenic in this marine animal.

Animals↗
PubMed2005

Topical corticosteroids for atopic eczema: clinical and cost effectiveness of once-daily vs. more frequent use.

BACKGROUND: Topical corticosteroids remain the mainstay of treatment for atopic eczema, yet there is uncertainty over the frequency of their use in terms of clinical and cost effectiveness. OBJECTIVES: To assess the clinical and cost effectiveness of once-daily vs. more frequent use of same-potency topical corticosteroids in atopic eczema. METHODS: A systematic review of the clinical and cost-effectiveness literature was undertaken, together with a cost-minimization analysis. RESULTS: The review identified a sparse literature, comprising one previous systematic review and 10 randomized controlled trials (RCTs). No published cost-effectiveness studies were identified. RCTs were focused on potent topical corticosteroids (eight RCTs), with no trials (RCTs/controlled clinical trials) identified on mild potency products. There was broad heterogeneity in trial methods, and therefore we considered outcomes according to: (i) at least a good response or 50% improvement, and (ii) eczema rated as cleared or controlled. Studies found little difference between once-daily and more frequent use of topical corticosteroids. The literature on moderately potent and potent corticosteroids offered no basis for favouring once-daily or more frequent use, although some significant differences favouring twice-daily treatment were identified. One RCT on very potent products favoured three times daily use on the basis of clinical response, but reported no difference in the numbers with at least a good response. Given the similar outcomes seen in clinical effectiveness a cost-minimization approach was adopted to consider cost effectiveness, in order to identify the least-cost option. However, cost-minimization analysis proved complex due to wide variations in product price, with the relative cost of product comparisons by frequency proving the most important factor in determining the least-cost alternative. CONCLUSIONS: This review has not identified any clear differences in outcomes between once-daily and more frequent application of topical corticosteroids. We would encourage prescribing clinicians to consider the once-daily use of topical corticosteroids when making treatment decisions for patients with atopic eczema. However, we find that the literature on clinical effectiveness is limited and a broader understanding of compliance and phobia associated with topical steroids is needed to inform on this issue.

Administration, Cutaneous↗
PubMed2005

A methodological review of how heterogeneity has been examined in systematic reviews of diagnostic test accuracy.

OBJECTIVES: To review how heterogeneity has been examined in systematic reviews of diagnostic test accuracy studies. DATA SOURCES: Centre for Reviews and Dissemination's Database of Abstracts of Reviews of Effects (DARE). REVIEW METHODS: Systematic reviews that evaluated a diagnostic or screening test by including studies that compared a test with a reference test were identified from DARE. Reviews for which structured abstracts had been written up to December 2002 were screened for inclusion. Data extraction was undertaken using standardised data extraction forms. RESULTS: A total of 189 systematic reviews met the inclusion criteria. The median number of studies included was 18. Meta-analyses have a higher number with a median of 22 studies compared with 11 for narrative reviews. Graphical plots to demonstrate the spread in study results were provided in 56% of meta-analyses; in 79% these were plots of sensitivity and specificity in the receiver operating characteristic (ROC) space. Statistical tests to identify heterogeneity were used in 32% of reviews: 41% of meta-analyses and 9% of reviews using narrative syntheses. The chi-squared test and Fisher's exact test to assess heterogeneity in individual aspects of test performance were the most common. In contrast, only 16% of meta-analyses used correlation coefficients to test for a threshold effect. A narrative synthesis was used in 30% of reviews. Of the meta-analyses, 52% carried out statistical pooling alone, 18% conducted only summary receiver operator characteristic (SROC) analyses and 30% used both methods of statistical synthesis. For those undertaking SROC analyses, the main differences between the models used were the weights chosen for the regression models, although in 42% of cases the use of, or choice of, weight was not provided. The proportion of reviews using statistical pooling alone has declined from 67% in 1995 to 42% in 2001, with a corresponding increase in the use of SROC methods, from 33% to 58%. However, two-thirds of those using SROC methods also carried out statistical pooling rather than presenting only SROC models. Reviews using SROC analyses also tended to present their results as some combination of sensitivity and specificity rather than using alternative, perhaps less clinically meaningful, means of data presentation such as diagnostic odds ratios. Three-quarters of meta-analyses attempted to investigate statistically possible sources of variation, using subgroup analysis or regression analysis. The impact of clinical or socio-demographic variables was investigated in 74% of these reviews and test- or threshold-related variables in 79%. At least one quality-related variable was investigated in 63% of reviews. Within this subset, the most commonly considered variables were the use of blinding, sample size, the reference test used and the avoidance of verification bias. CONCLUSIONS: The emphasis on pooling individual aspects of diagnostic test performance and the under-use of statistical tests and graphical approaches to identify heterogeneity perhaps reflect the uncertainty in the most appropriate methods to use and also greater familiarity with more traditional indices of test accuracy. This indicates the difficulty and complexity of carrying out such reviews. In these cases it is strongly suggested that meta-analyses are carried out with the involvement of a statistician familiar with the field. Further methodological work on the statistical methods available for combining diagnostic test accuracy studies is needed, as are sufficiently large, prospectively designed primary studies of diagnostic test accuracy comparing two or more tests for the same target disorder. Use of individual patient data meta-analysis in diagnostic test accuracy reviews should be explored to allow heterogeneity to be considered in more detail.

Diagnostic Tests, Routine↗
PubMed2005

Natural history of asymptomatic bile duct stones at time of cholecystectomy.

OBJECTIVES: There is little data on the natural history of asymptomatic bile duct stones and hence there is uncertainty on the management of asymptomatic bile duct stones discovered incidentally at the time of laparoscopic cholecystectomy. We retrospectively reviewed a group of patients who had previously underwent laparoscopic cholecystectomy, but who did not have a pre-operative suspicion of intra-ductal stones, to determine if any biliary complications had subsequently developed. A group of patients who had no pre-operative suspicion of intra-ductal stones, but routinely underwent intraoperative cholangiogram (IOC) at time of cholecystectomy, served as the control group. METHODS: A telephone questionnaire was completed by each patient's family practitioner in 59 of 79 (75%) patients who underwent laparoscopic cholecystectomy. In the remaining 20 patients additional information was obtained from hospital records and from the central services agency (CSA). These patients had no pre-operative suspicion of bile duct stones and therefore did not undergo an IOC or ERCP. The control group (73 patients) had no pre-operative suspicion of bile duct stones but had a routine IOC performed to define the biliary anatomy. RESULTS: 59 patients were followed up for an average of 57 months (range 30-78 months) after laparoscopic cholecystectomy. None of these patients developed pancreatitis, jaundice, deranged liver function tests (LFT's), or required ERCP or other biliary intervention. In the additional 20 patients where no information was available from the family practitioner, 11 patients had follow up appointments with no documentation of biliary complications or abnormal LFT's. 19 of 20 patients were traceable through the CSA and were all alive. Only 1 patient was untraceable and therefore unknown if biliary complications had developed. In the control group, 4 of 73 (6%) patients had intraductal stones detected and extracted. Thus the prevalence of asymptomatic bile duct stones during the time of cholecystectomy in our population was 6%. CONCLUSIONS: Asymptomatic bile duct stones discovered at the time of cholecystectomy do not appear to cause any biliary complications over a 5-year follow up. Incidental bile duct stones found in patients undergoing laparoscopic cholecystectomy may not need to be removed.

Adult↗
PubMed2004

Clinical and cost-effectiveness of once-daily versus more frequent use of same potency topical corticosteroids for atopic eczema: a systematic review and economic evaluation.

OBJECTIVES: To assess the clinical and cost-effectiveness of once-daily use of topical corticosteroids versus more frequent use of same-potency topical corticosteroids in the treatment of people with atopic eczema. DATA SOURCES: Electronic databases. Bibliographies of included studies and related papers. Experts in the field. Manufacturer submissions to the National Institute for Clinical Excellence. REVIEW METHODS: Studies were assessed for inclusion according to predefined criteria by two reviewers. Data extraction and quality assessment were undertaken by one reviewer and checked by a second reviewer. Clinical effectiveness data were synthesised through a narrative review with full tabulation of results. RESULTS: One RCT comparing moderately potent corticosteroids, eight RCTs comparing potent corticosteroids and one RCT comparing very potent corticosteroids were included. No RCTs or CCTs of mild corticosteroids were eligible. Most RCTs were of poor methodological quality, although two were judged to be of good quality. The only study that compared moderately potent corticosteroids found no significant difference between once- and twice-daily application. For potent corticosteroids, some statistically significant differences in numbers of patients responding to treatment were identified favouring twice-daily treatment, but these were inconsistent between physician and patient assessment and outcomes selected for analysis. Two studies found a significant improvement in some symptoms with once-daily mometasone furoate compared with twice-daily application of a different active compound, while a third study found no significant differences. One good-quality study favoured twice-daily application of fluticasone propionate ointment, while other studies found no significant difference or an improvement in one symptom but not others. The only study comparing very potent corticosteroids found a statistically significant difference in comparative clinical response in favour of three-times daily treatment, but no difference in number of patients with at least a good response. There appears to be little difference in the frequency or severity of short-term events, however data are limited. No published economic evaluations were identified. Given findings on clinical effectiveness, where outcomes from the comparators are similar, the relative cost-effectiveness of once-daily versus more frequent application of topical corticosteroids becomes a case of cost-minimisation, where the least-cost alternative should be favoured, all else being equal. Topical corticosteroid products included in this review have a wide variation in price; the cost per 30 g/30 ml varies between GBP0.60 and GBP4.88. Specific decisions on the least-cost alternative, between once-daily and more frequent application of products, will be determined by the relative price of the products being compared. Where patients can be appropriately prescribed once-daily treatment of a similarly priced product, a reduction in the quantity of topical corticosteroid used will be expected. However, issues related to pack size for prescribed products and subsequent waste (unused product) could easily erode any potential saving. The potential cost-savings on prescribed products are very small at a patient level; although given the large numbers of patients with atopic eczema, cost savings in theory could be substantial. The presence of specifically marketed 'once-daily' topical corticosteroids, which are relatively expensive (per unit price), may result in additional costs should there be a general recommendation in favour of once-daily use of topical corticosteroids, compared to more frequent use. CONCLUSIONS: The literature is very limited; that available indicates the clinical effectiveness of once-daily and more frequent application of potent topical corticosteroids is very similar, but it does not offer a basis for favouring either option. The cost-effectiveness of once-daily versus more frequent use will depend on the generalisability of the findings to the specific treatment decision and the relative product prices. The trials included in this review generally refer to moderate to severe atopic eczema, whereas most patients have mild disease, and furthermore most of the included trials report on potent topical corticosteroids (eight of 10 RCTs); therefore the generalisability of the findings is limited. Further research is required on the clinical and cost-effectiveness of once-daily versus more frequent use of same potency corticosteroids, specifically on mild potency products for mild to moderate atopic eczema. Outcomes should include quality of life and compliance.

Administration, Topical↗
PubMed2002

NAN fusions: a synthetic sialidase reporter gene as a sensitive and versatile partner for GUS.

GUS continues to be the reporter of choice for many gene fusion applications, due to the unparalleled sensitivity of the encoded enzyme and the ease with which it can be quantified in cell-free extracts and visualized histochemically in cells and tissues. A compatible and functionally equivalent reporter gene would facilitate dual promoter studies and internal standardization of expression analyses in the same plant. A search for a candidate enzyme activity not found in plants, which might form the basis of a novel GUS-compatible reporter system, led us to investigate nanH, a Clostridium perfringens gene which encodes the so-called 'small' cytoplasmic sialidase. Expression of the native, AT-rich nanH gene in transgenic plants did not, however, result in detectable sialidase activity. For this reason, a codon-optimized derivative, NAN, was synthesized which possesses a GC content similar to that found in highly expressed plant genes. NAN enzyme activity was expressed at high levels in both stably and transiently transformed cells, possessed kinetic and stability properties similar to those of GUS, and showed optimal activity in GUS buffer. Moreover, NAN and GUS activity could be visualized simultaneously in polyacrylamide gels using the corresponding methylumbelliferone-based substrates, and in whole seedlings and tissue sections using the histochemical substrates 5-bromo-4-chloro-3-indolyl alpha-d-N-acetylneuraminic acid (X-NeuNAc) and 5-bromo-6-chloro-3-indolyl beta-d-glucuronide (X-GlucM), respectively.

Amino Acid Sequence↗
PubMed2001

Legionella pneumophila is internalized by a macropinocytotic uptake pathway controlled by the Dot/Icm system and the mouse Lgn1 locus.

The products of the Legionella pneumophila dot/icm genes enable the bacterium to replicate within a macrophage vacuole. This study demonstrates that the Dot/Icm machinery promotes macropinocytotic uptake of L. pneumophila into mouse macrophages. In mouse strains harboring a permissive Lgn1 allele, L. pneumophila promoted formation of vacuoles that were morphologically similar to macropinosomes and dependent on the presence of an intact Dot/Icm system. Macropinosome formation appeared to occur during, rather than after, the closure of the plasma membrane about the bacterium, since a fluid-phase marker preloaded into the macrophage endocytic path failed to label the bacterium-laden macropinosome. The resulting macropinosomes were rich in GM1 gangliosides and glycosylphosphatidylinositol-linked proteins. The Lgn1 allele restrictive for L. pneumophila intracellular replication prevented dot/icm-dependent macropinocytosis, with the result that phagosomes bearing the microorganism were targeted into the endocytic network. Analysis of macrophages from recombinant inbred mouse strains support the model that macropinocytotic uptake is controlled by the Lgn1 locus. These results indicate that the products of the dot/icm genes and Lgn1 are involved in controlling an internalization route initiated at the time of bacterial contact with the plasma membrane.

Animals↗
PubMed2001

Machine perfusion for kidneys: how to do it at minimal cost.

Due to a shortage of organs for transplantation, many centres use marginal grafts to increase their donor pool. As kidneys from non-heart-beating donors (NHBD) have sustained initial ischaemic damage, their viability is difficult to predict. Hypothermic pulsatile perfusion has not only been used to improve the condition of such grafts, but also allows viability assessment. Suitable systems are becoming more readily available, but they are expensive. We have used existing dialysis equipment with modified sterilised inserts to create a pulsatile hypothermic perfusion system. With this system, 41 NHBD kidneys were perfused for up to 8 h; their intravascular renal resistance (IRVR), flow characteristics as well as glutathione S transferase (GST) measurements were performed to assess viability. This hypothermic pulsatile perfusion system is now an integral component of our NHBD programme.

Costs and Cost Analysis↗
PubMed2001

Selenium, cadmium, copper, and zinc concentrations in sediments and mullet (Mugil cephalus) from the southern Basin of Lake Macquarie, NSW, Australia.

Selenium, cadmium, copper, and zinc concentrations were measured in sediments and the tissues of mullet (Mugil cephalus) collected from the southern basin of Lake Macquarie, NSW, Australia. Trace metals in surficial sediments are enriched in trace metals relative to background concentrations (selenium, 3-19; cadmium, 14-42; copper, 1.5-3.6; zinc, 0.77-2.2 times background). Selenium, cadmium, and copper in Lake Macquarie mullet tissues are elevated compared to those in mullet collected from the Clyde River estuary, a relatively pristine location. Selenium and copper concentrations are also elevated compared to those reported in mullet tissues from other nonpolluted coastal environments. Zinc concentrations in Lake Macquarie mullet muscle tissues are significantly higher than those in muscle tissues of mullet from the Clyde River estuary, but mullet from both locations have similar zinc concentrations in other tissues. These results show that contamination of sediment with trace metals has resulted in elevated trace metals in the benthic feeding fish M. cephalus. Little of the variation of trace metal concentrations between fish was explained by variation in mass. Selenium concentrations in mullet are of concern in muscle tissues as they are above recommended acceptable limits for safe human consumption, while concentrations in tissues are at levels that may effect fish growth, reproduction, and survival. Copper concentrations in mullet tissues are also at levels that may reduce fish growth.

Animals↗
PubMed2001

Changes in selenium, copper, cadmium, and zinc concentrations in mullet (Mugil cephalus) from the southern basin of Lake Macquarie, Australia, in response to alteration of coal-fired power station fly ash handling procedures.

Selenium, copper, cadmium, and zinc concentrations were measured in mullet (Mugil cephalus) from the southern basin of Lake Macquarie, Australia, in 1997 to determine if improved ash-handling practices at an adjacent coal fired power station, implemented in 1995, had significantly lowered trace metal concentrations in mullet tissues. Mean muscle tissue concentrations of selenium (5.9 +/- 0.7 microg/g dry mass), copper (3.6 +/- 0.1 microg/g dry mass), and zinc (14 +/- 1 microg/g dry mass) are lower than previously reported for mullet analyzed in 1993 (10 +/- 2, 21 +/- 3, 27 +/- 3 microg/g dry mass, respectively). Cadmium concentrations in liver tissues increased from 2.3 +/- 0.3 to 6 +/- 2 microg/g dry mass. Significant intra-tissue correlations between metal concentrations were found for all tissues except muscle. Strong correlations of selenium, copper, and zinc concentrations were found in liver tissues, indicating a common primary source may exist for these metals, such as fly ash. All trace metals were found to have significant inter-tissue correlations, with strong correlations occurring for selenium between all tissues and for cadmium between all tissues except muscle. Regulation of copper, cadmium, and zinc appears to be occurring in muscle tissue. Selenium concentrations in mullet are still above levels considered to be of concern to human consumers. Trace metal concentrations are below that known to effect the health of fish. Mullet are directly exposed to trace metal concentrations as a result of feeding and the ingestion of contaminated sediment and detritus. Lower metal concentrations found in mullet tissues are attributed to the burial of highly contaminated sediment with material containing lower trace metal concentrations. Little of the variations in trace metal concentrations between mullet was explained by mass, gender, or age.

Air Pollutants↗
PubMed2001

EndB, a multidomain family 44 cellulase from Ruminococcus flavefaciens 17, binds to cellulose via a novel cellulose-binding module and to another R. flavefaciens protein via a dockerin domain.

The mechanisms by which cellulolytic enzymes and enzyme complexes in Ruminococcus spp. bind to cellulose are not fully understood. The product of the newly isolated cellulase gene endB from Ruminococcus flavefaciens 17 was purified as a His-tagged product after expression in Escherichia coli and found to be able to bind directly to crystalline cellulose. The ability to bind cellulose is shown to be associated with a novel cellulose-binding module (CBM) located within a region of 200 amino acids that is unrelated to known protein sequences. EndB (808 amino acids) also contains a catalytic domain belonging to glycoside hydrolase family 44 and a C-terminal dockerin-like domain. Purified EndB is also shown to bind specifically via its dockerin domain to a polypeptide of ca. 130 kDa present among supernatant proteins from Avicel-grown R. flavefaciens that attach to cellulose. The protein to which EndB attaches is a strong candidate for the scaffolding component of a cellulosome-like multienzyme complex recently identified in this species (S.-Y. Ding et al., J. Bacteriol. 183:1945-1953, 2001). It is concluded that binding of EndB to cellulose may occur both through its own CBM and potentially also through its involvement in a cellulosome complex.

Amino Acid Sequence↗
PubMed2001

A comparison of patient reading performance and preference: optical devices, handheld CCTV (Innoventions Magni-Cam), or stand-mounted CCTV (Optelec Clearview or TSI Genie).

BACKGROUND: Clinicians frequently prescribe reading devices for low vision patients having a central field loss. This study seeks to provide comparative information the clinician can use to assist patients in selecting the most cost-effective device(s) for reading. METHOD: In this study we compared optical devices with two types of closed-circuit televisions (CCTVs) that differed in two important characteristics: price, and whether the camera was stand-mounted with an X-Y table or whether the camera was handheld. A "within-subjects" design was used with 22 subjects. The primary comparisons between devices were subject reading speed, duration, and preference. RESULTS: Subject reading speed and duration were significantly greater with the CCTV systems than with optical devices; however, no significant performance differences were found between the two types of CCTVs. Patients did express a clear preference for one versus the other type of CCTV, with an overall preference for the stand-mounted system. When asked to consider the price differential between types of CCTVs, patient preferences were about equally divided. CONCLUSIONS: Clinicians can expect significantly better initial reading performance for patients with central visual-field losses when reading with CCTVs versus optical devices. Handheld CCTVs, when compared with stand-mounted systems, are less expensive, provide equal performance, and have slightly lower subject preference ratings. The current study provides clinicians with objective performance data and subjective preference data that can be used to help patients with central visual-field losses select the most cost-effective reading device.

Aged↗
PubMed2000

The trouble with kidneys derived from the non heart-beating donor: a single center 10-year experience.

BACKGROUND: The demand for renal transplantation has increasingly outstripped the supply of donor organs especially over the past 10 years. Although related and unrelated live donation is being promoted as one option for increasing the donor pool, it is unlikely that this will in itself be able to bridge the gap. Non-heart beating donors (NHBD) can provide an alternative supply of organs, which should substantially increase the donor pool. METHODS: In Newcastle, NHBD kidneys have been used for transplantation for a period of 10 years. In the early period (1988-1993) excellent results were obtained (90.5% success); however, these donors were controlled NHBD, Maastricht category III. In the second phase (1994-1998) increasing numbers of donors were obtained from the Accident and Emergency Department unit. These were failed resuscitation for cardiac arrest (category II). The rates of success in this period were poor (45.5% success) and the program was halted. The third phase of the program used machine perfusion of the kidneys and glutathione S transferase enzyme analysis to assess viability. RESULTS: Using such approaches renal transplants from largely category II donors produced a success rate of 92.3% which was significantly better than the phase II period of the program (P=0.023, Fisher two-tail test). CONCLUSION: Machine perfusion and viability assessment of NHB kidneys in phase III of the program has increased our donor pool as well as improved the graft survival. This is particularly relevant for the use of the category II NHB donor where the incidence of primary nonfunction was high, illustrated by phase II where machine perfusion/viability assessment was not used.

Adult↗