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Full-Text Articles in Life Sciences

Prevention Of Staphylococcus Epidermidis Biofilm Formation Using A Low-Temperature Processed Silver-Doped Phenyltriethoxysilane Sol–Gel Coating, Niall Stobie, Brendan Duffy, Declan Mccormack, John Colreavy, Martha Hidalgo, Patrick Mchale, Steven Hinder Dec 2007

Prevention Of Staphylococcus Epidermidis Biofilm Formation Using A Low-Temperature Processed Silver-Doped Phenyltriethoxysilane Sol–Gel Coating, Niall Stobie, Brendan Duffy, Declan Mccormack, John Colreavy, Martha Hidalgo, Patrick Mchale, Steven Hinder

Articles

Sol–gel coatings which elute bioactive silver ions are presented as a potential solution to the problem of biofilm formation on indwelling surfaces. There is evidence that high-temperature processing of such materials can lead to diffusion of silver away from the coating surface, reducing the amount of available silver. In this study, we report the biofilm inhibition of a Staphylococcus epidermidis biofilm using a low-temperature processed silver-doped phenyltriethoxysilane sol–gel coating. The incorporation of a silver salt into a sol–gel matrix resulted in an initial high release of silver in de-ionised water and physiological buffered saline (PBS), followed by a lower sustained …


Extending And Measuring The Quality Of Fresh-Cut Fruit And Vegetables: A Review, Catherine Barry-Ryan, Ana Belen Martin-Diana, Daniel Rico, J. Barat Jul 2007

Extending And Measuring The Quality Of Fresh-Cut Fruit And Vegetables: A Review, Catherine Barry-Ryan, Ana Belen Martin-Diana, Daniel Rico, J. Barat

Articles

The market sales of ready-to-use fresh vegetables have grown rapidly in recent decades as a result of changes in consumer attitudes, especially consumption of fresh-cut lettuce and carrot due to their use in prepared salads. Chlorine solutions have been widely used to sanitise fruit and vegetables in the fresh-cut industry. However, the association of chlorine with the possible formation of carcinogenic chlorinated compounds in water has called into question the use of chlorine in food processing. There is a real need to find alternatives for preservation of fresh-cut fruit and vegetables in order to improve the efficacy of washing treatments. …


The Acyl-Coa Thioesterase I (Acot1) Is Regulated By The Peroxisome Proliferator-Activated Receptor Alpha And Hepatocyte Nuclear Factor 4 Alpha Via A Distal Response Element In The Promotor., Bikesh Dongol, Yatrik Shah, Insook Kim, Frank J. Gonzalez, Mary Hunt May 2007

The Acyl-Coa Thioesterase I (Acot1) Is Regulated By The Peroxisome Proliferator-Activated Receptor Alpha And Hepatocyte Nuclear Factor 4 Alpha Via A Distal Response Element In The Promotor., Bikesh Dongol, Yatrik Shah, Insook Kim, Frank J. Gonzalez, Mary Hunt

Articles

The cytosolic acyl-CoA thioesterase I (Acot1) is an enzyme that hydrolyzes longchain acyl-CoAs of C12-C20-CoA in chain-length, to the free fatty acid and coenzyme A. Acot1 was previously shown to be strongly upregulated at mRNA and protein level in rodents by fibrates. In this study, we show that Acot1 mRNA levels were increased 90-fold in liver by treatment with Wy-14,643 and that Acot1 mRNA is also increased 15-fold in the liver of hepatocyte nuclear factor 4 alpha (HNF4a) knockout animals. Our study identified a direct repeat 1 (DR1) located in the Acot1 gene promotor in mouse, which binds the peroxisome …


A Peroxisomal Acyltransferase In Mouse Identifies A Novel Pathway For Taurine Conjugation Of Fatty Acids., Sarah-Jayne Reilly, Eithne O'Shea, O'Byrne James, Stefan Alexson, Mary Hunt Jan 2007

A Peroxisomal Acyltransferase In Mouse Identifies A Novel Pathway For Taurine Conjugation Of Fatty Acids., Sarah-Jayne Reilly, Eithne O'Shea, O'Byrne James, Stefan Alexson, Mary Hunt

Articles

A wide variety of endogenous carboxylic acids and xenobiotics are conjugated with amino acids, before excretion in urine or bile. The conjugation of carboxylic acids and bile acids with taurine and glycine has been widely characterized and de-novo synthesized bile acids are conjugated to either glycine or taurine in peroxisomes. Peroxisomes are also involved in the oxidation of several other lipid molecules, such as very long chain acyl-CoAs, branched chain acyl-CoAs and prostaglandins. In this study we have now identified a novel peroxisomal enzyme called acyl-CoA:amino acid N-acyltransferase (ACNAT1). Recombinantly expressed ACNAT1 acts as an acyltransferase that efficiently conjugates very …


Extending And Measuring The Quality Of Fresh-Cut Fruit And Vegetables: A Review, Ana Belen Martin-Diana, Daniel Rico, Gary Henehan, Jesus Maria Frias, J. Barat Jan 2007

Extending And Measuring The Quality Of Fresh-Cut Fruit And Vegetables: A Review, Ana Belen Martin-Diana, Daniel Rico, Gary Henehan, Jesus Maria Frias, J. Barat

Articles

The market sales of ready - to - use vegetables have grown rapidly in recent decades as a result of changes in consumer attitudes especially consumption of fresh-cut lettuce and carrot due to their use in prepared salads. Chlorine solutions have been widely used to sanitise fruit and vegetables in the fresh-cut industry. However, the association of chlorine with the possible formation of carcinogenic chlorinated compounds in water has called into question the use of chlorine in food processing. There is a real need to find alternatives for preservation of fresh-cut fruit and vegetables in order to improve the efficacy …


Alternative Exon Usage Selectively Determines Both Tissue Distribution And Subcellular Localization Of The Acyl-Coa Thioesterase 7 Gene Products., Mary Hunt, Sinead Greene, Kjell Hultenby, L. Thomas Svensson, Susanna Engberg, Stefan E H Alexson Jan 2007

Alternative Exon Usage Selectively Determines Both Tissue Distribution And Subcellular Localization Of The Acyl-Coa Thioesterase 7 Gene Products., Mary Hunt, Sinead Greene, Kjell Hultenby, L. Thomas Svensson, Susanna Engberg, Stefan E H Alexson

Articles

Acyl-CoA thioesterases (ACOTs) catalyze the hydrolysis of acyl-CoAs to free fatty acids and coenzyme A. Recent studies have demonstrated that one gene named Acot7, reported to be mainly expressed in brain and testis, is transcribed in several different isoforms by alternative usage of first exons. Strongly decreased levels of ACOT7 activity and protein in both mitochondria and cytosol was reported in patients diagnosed with fatty acid oxidation defects, linking ACOT7 function to regulation of fatty acid oxidation in other tissues. In this study, we have identified five possible first exons in mouse Acot7 (Acot7a-e) and show that all five first …


Peroxisomes Contain A Specific Phytanoly-Coa/Pristanoyl-Coa Thioesterase Acting As A Novel Auxiliary Enzyme In Alpha-And Beta-Oxidation Of Methyl-Branched Fatty Acids In Mouse, Maria Westin, Mary Hunt, Stefan Alexson Jan 2007

Peroxisomes Contain A Specific Phytanoly-Coa/Pristanoyl-Coa Thioesterase Acting As A Novel Auxiliary Enzyme In Alpha-And Beta-Oxidation Of Methyl-Branched Fatty Acids In Mouse, Maria Westin, Mary Hunt, Stefan Alexson

Articles

Phytanic acid and pristanic acid are derived from phytol, which enter the body via the diet. Phytanic acid contains a methyl group in position three and therefore cannot undergo b-oxidation directly, but instead must first undergo a-oxidation to pristanic acid, which then enters b-oxidation. Both these pathways occur in peroxisomes, and in this study we have identified a novel peroxisomal acyl-CoA thioesterase, named ACOT6, which we show is specifically involved in phytanic acid and pristanic acid metabolism. Sequence analysis of ACOT6 revealed a putative peroxisomal targeting signal at the C-terminal end, and cellular localization experiments verified it as a peroxisomal …


Nitrocellulose As A General Tool For Fungal Slide Mounts, David Barry, Cecilia Chan, Gwilym A. Williams Jan 2007

Nitrocellulose As A General Tool For Fungal Slide Mounts, David Barry, Cecilia Chan, Gwilym A. Williams

Articles

No abstract provided.


Development And Assessment Of A Rapid Method To Detect Escherichia Coli O26, O111 And O157 In Retail Minced Beef., Mary Murphy, Anne Carroll, Paul Whyte, Micheál O'Mahoney, Wayne Anderson, Eleanor Mcnamara, Seamus Fanning, Ciara Walsh Jan 2007

Development And Assessment Of A Rapid Method To Detect Escherichia Coli O26, O111 And O157 In Retail Minced Beef., Mary Murphy, Anne Carroll, Paul Whyte, Micheál O'Mahoney, Wayne Anderson, Eleanor Mcnamara, Seamus Fanning, Ciara Walsh

Articles

A molecular-based detection method was developed to detect Escherichia coli O26, O111 and O157 in minced (ground) beef samples. This method consists of an initial overnight enrichment in modified tryptone soya broth (mTSB) and novobiocin prior to DNA extraction and subsequent serogrouping using a triplex PCR. This method has a low limit of detection and results are available within 24 hours of receipt of samples. Once optimized, this rapid method was utilized to determine the prevalence of these E. coli serogroups in six hundred minced beef samples all of which were previously examined by immunomagnetic separation (IMS) and selective plating …


Chlamydia Trachomatis Detection In Cervical Preservcyt Specimens From An Irish Urban Female Population, Helen Keegan, Fergus Ryan, Alison Malkin, M. Griffin, Helen Lambkin Jan 2007

Chlamydia Trachomatis Detection In Cervical Preservcyt Specimens From An Irish Urban Female Population, Helen Keegan, Fergus Ryan, Alison Malkin, M. Griffin, Helen Lambkin

Articles

Objective: The aim of this study was to determine the prevalence of cervical Chlamydia trachomatis infection by polymerase chain reaction (PCR) in urban women undergoing routine cervical cytological screening and to investigate the relationship with age, cytology, smoking status and concurrent human papillomavirus (HPV) infection. Methods: A total of 996 women (age range 16–69 years) attending general practitioners for routine liquid-based cervical smear screening in the Dublin area were recruited in the study of prevalence of C. trachomatis. Informed consent was obtained and liquid-based cytology (LBC) specimens were sent for cytological screening. DNA was extracted from residual LBC and tested …


Human Papillomavirus Prevalence And Genotypes In An Opportunistically Screened Irish Female Population, Helen Keegan, Fergus Ryan, Alison Malkin, Mairead Griffin, Helen Lambkin Jan 2007

Human Papillomavirus Prevalence And Genotypes In An Opportunistically Screened Irish Female Population, Helen Keegan, Fergus Ryan, Alison Malkin, Mairead Griffin, Helen Lambkin

Articles

This study aims to evaluate human papillomavirus (HPV) prevalence and predominating genotypes in liquid-based cervical cytology samples from an Irish urban female population. In addition to use of routine cervical cytology testing, women are screened for HPV using the MY09/11 primers for the HPV L1 gene and primers for β-globin amplification in a multiplex format. Overall, 996 women between the ages of 16 and 72 years (average age: 35) are included in the study and HPV prevalence was 19.8%. Cytology results showed that 88.9% were normal, 9% borderline or mild dyskaryosis, 1.1% moderate dyskaryosis and 0.9% severe dyskaryosis. Human papillomavirus …


Simultaneous Modelling Of The Thermal Degradationa Kinetics Of Pectin, Daniel Rico, Ana Belen Martin-Diana, Catherine Barry-Ryan, Gary Henehan, Jesus Maria Frias Jan 2007

Simultaneous Modelling Of The Thermal Degradationa Kinetics Of Pectin, Daniel Rico, Ana Belen Martin-Diana, Catherine Barry-Ryan, Gary Henehan, Jesus Maria Frias

Articles

The thermal degradation kinetics of pectin methylesterase (PME) from carrot and lettuce were studied. Fresh extracts were exposed to temperatures from 55 to 70 °C until the enzyme was inactivated. A model based on the presence of two forms of the enzyme, one active and one non-active, is proposed. The natural variability of the PME activity was taken into the model in the form of normally distributed random effects. The common model parameters obtained (cleavage constant (0.0395±0.0062 s−1), degradation constant (0.556±0.112 s−1), cleavage energy of activation (469±23 kJ mol−1) and degradation energy of activation …


Proteinparser:A Community Based Tool For The Generation Of A Detailed Protein Consensus And Fasta Output, Barry Ryan, Ronan Barrett Jan 2007

Proteinparser:A Community Based Tool For The Generation Of A Detailed Protein Consensus And Fasta Output, Barry Ryan, Ronan Barrett

Articles

Comparison of bioinformatic data is a common application in the life sciences and beyond. In this communication, a novel Java based software tool, ProteinParser, is outlined. This soft- ware tool calculates a detailed consensus, or most common, amino acid at a given position in an aligned protein set, whilst also generating a full consensus protein FASTA output. A second application of this software tool, computing a consensus amino acid given a toler- ance threshold, is also demonstrated. The phytase and the common bacterial �-lactamase proteins are analysed as ‘proof of concept’ examples. Consensus proteins, as generated by ProteinParser, are regularly …


Characteristics Of Cooked Chickpeas And Soybeans During Combined Microwave–Convective Hot Air Drying, Aoife Gowen, Nissreen Abu-Ghannam, Jesus Maria Frias, Jorge Oliveira Jan 2007

Characteristics Of Cooked Chickpeas And Soybeans During Combined Microwave–Convective Hot Air Drying, Aoife Gowen, Nissreen Abu-Ghannam, Jesus Maria Frias, Jorge Oliveira

Articles

Moisture content, shrinkage, water activity (Aw), color and texture of cooked chickpeas and soybeans during convective, microwave and combined microwave–convective drying were studied. Combined drying was significantly (P < 0.05) faster than either convective or microwave drying, and resulted in less shrinkage of the dehydrated product. Rapid burning occurred when samples were dried below a Aw of 0.27 ± 0.07 for chickpeas (P < 0.05), and 0.13 ± 0.04 for soybeans (P < 0.05). Both chickpeas and soybeans displayed a transitional behavior in texture when dried to a Aw below 0.40 ± 0.10 (P < 0.05) for chickpeas, and below 0.63 ± 0.15 (P < 0.05) for soybeans, when samples became brittle. Shelf stable dehydrated chickpea and soybean products with low water activity (Aw = 0.35) and good visual quality could be obtained within 14 min of combination drying.


Calcium For Extending The Shelf Life Of Fresh Whole And Minimally Processed Fruits And Vegetables, Ana Belen Martin-Diana, Daniel Rico, Jesus Maria Frias, J. Barat, Gary Henehan Jan 2007

Calcium For Extending The Shelf Life Of Fresh Whole And Minimally Processed Fruits And Vegetables, Ana Belen Martin-Diana, Daniel Rico, Jesus Maria Frias, J. Barat, Gary Henehan

Articles

The preservation of quality of fresh products is relevant for the industry due to its economic impact. This paper presents a comprehensive review of the use of different sources of calcium to preserve fresh fruits and vegetables in order to extend the shelf life and enhance the nutritional value. Emphasis is on discussing about the best sources of calcium, concentration, temperature and method of application, suitability of the commodities; and some hints for the cost/benefit analysis are presented.


Arginine-To-Lysine Substitutions Influence Recombinant Horseradish Peroxidase Stability And Immobilisation Effectiveness., Barry Ryan, CiaráN Fagan Jan 2007

Arginine-To-Lysine Substitutions Influence Recombinant Horseradish Peroxidase Stability And Immobilisation Effectiveness., Barry Ryan, CiaráN Fagan

Articles

Background: Horseradish Peroxidase (HRP) plays important roles in many biotechnological fields, including diagnostics, biosensors and biocatalysis. Often, it is used in immobilised form. With conventional immobilisation techniques, the enzyme adheres in random orientation: the active site may face the solid phase rather than bulk medium, impeding substrate access and leading to sub-optimal catalytic performance. The ability to immobilise HRP in a directional manner, such that the active site would always face outwards from the insoluble matrix, would maximise the immobilised enzyme’s catalytic potential and could increase HRP’s range of actual and potential applications. Results: We have replaced arginine residues on …


Effects Of Single Mutations On The Stability Of Horseradish Peroxidase To Hydrogen Peroxide., Barry Ryan, CiaráN Fagan Jan 2007

Effects Of Single Mutations On The Stability Of Horseradish Peroxidase To Hydrogen Peroxide., Barry Ryan, CiaráN Fagan

Articles

Horseradish Peroxidase (HRP) is a commonly used enzyme in many biotechnological fields. Improvement of HRP stability would further increase its potential application range. In the present study, thirteen single- and three double- mutants of solvent exposed, proximal lysine and glutamic acid residues were analysed for enhanced H2O2 stability. Additionally, five single- and one pentuple-consensus mutants were investigated. Most mutants displayed little or no alteration in H2O2 stability; however, three (K232N, K241F and T110V) exhibit significantly increased H2O2 tolerances of 25- (T110V), 18- (K232N), and 12- fold (K241F). This improved stability may be due to an altered enzyme-H2O2 catalysis pathway or …


Effects Of Mutations In The Helix G Region Of Horseradish Peroxidase, Barry Ryan, CiaráN Ó'FáGáIn Jan 2007

Effects Of Mutations In The Helix G Region Of Horseradish Peroxidase, Barry Ryan, CiaráN Ó'FáGáIn

Articles

Horseradish Peroxidase (HRP) has long attracted intense research interest and is used in many biotechnological fields, including diagnostics, biosensors and biocatalysis. Enhancement of HRP catalytic activity and/or stability would further increase its usefulness. Based on prior art, we substituted solvent-exposed lysine and glutamic acid residues near the proximal helix G (Lys 232, 241; Glu 238, 239) and between helices F and F’ (Lys 174). Three single mutants (K232N, K232F, K241N) demonstrated increased stabilities against heat (up to two-fold) and solvents (up to four-fold). Stability gains are likely due to improved hydrogen bonding and space-fill characteristics introduced by the relevant substitution. …


Ef Fi Cacy Of Steamer Jet-Injection As Alternative To Chlorine In Fresh-Cut Lettuce, Daniel Rico, Ana Belen Martin-Diana, Jesus Maria Frias, J. Barat, Gary Henehan, Catherine Barry-Ryan Jan 2007

Ef Fi Cacy Of Steamer Jet-Injection As Alternative To Chlorine In Fresh-Cut Lettuce, Daniel Rico, Ana Belen Martin-Diana, Jesus Maria Frias, J. Barat, Gary Henehan, Catherine Barry-Ryan

Articles

The use of calcium lactate solutions has been shown to be a healthy alternative to chlorine washing in order to maintain the shelf-life of fresh-cut products. The aim of this research was to analyse the effects of calcium lactate (15 g L−1) treatment at 25 °C and 50 °C (heat-shock) on the textural properties of sliced carrots and to compare those with the chlorine treatment (120 mg L−1) widely used in industry. Several direct and indirect markers of textural changes in carrots during storage were used: Instron textural analysis, Cryo-SEM and optical microscopic, sensory analysis, pectin …


Efficacy Of Steamer Jet-Injection As Alternative To Chlorine In Fresh-Cut Lettuce, Ana Belen Martin-Diana, Daniel Rico, Catherine Barry-Ryan, Jesus Maria Frias, Gary Henehan, J. Barat Jan 2007

Efficacy Of Steamer Jet-Injection As Alternative To Chlorine In Fresh-Cut Lettuce, Ana Belen Martin-Diana, Daniel Rico, Catherine Barry-Ryan, Jesus Maria Frias, Gary Henehan, J. Barat

Articles

Short-time steam processing was used as an alternative to chlorine (100 mg L−1) in sanitising fresh-cut lettuce. Quality (pH, water content, colour, potential browning, browning-related enzymes and texture), safety (mesophilic counts) and antioxidant markers (ascorbic and carotenoids) were monitored in lettuce stored for 10 days at 4 °C. The steam treatment produced a shocking effect on lettuce metabolism, showing a significant (p < 0.05) reduction in respiration (from day 3 to 7) and a partial inactivation of browning-related enzymes. Both effects were reflected in a significant reduction of browning. From a safety point of view, steam treatment kept the mesophilic load as low as chlorine treatment, and significantly lowers than the water control. However, antioxidant content, especially ascorbic acid but also carotenoids in a lower degree, showed a reduction compared with chlorine-treated samples. Despite the lower visual browning in steam-treated samples, the sensory panel scored similar values of acceptability and fresh appearance for both samples similarity.


Enterobacter Sakazakii: An Emerging Microbe With Implications For Infant Health, N. R. Mullane, B. Healy, Ciara Walsh, C. Iversen, P. Whyte, P. G. Wall, T. Quinn, Seamus Fanning Jan 2007

Enterobacter Sakazakii: An Emerging Microbe With Implications For Infant Health, N. R. Mullane, B. Healy, Ciara Walsh, C. Iversen, P. Whyte, P. G. Wall, T. Quinn, Seamus Fanning

Articles

Enterobacter sakazakii (E. sakazakii) is an opportunistic pathogen and the aetiological agent in rare but life-threatening cases of meningitis, necrotizing enterocolitis, and sepsis in infants. Among infants, those at greatest risk are neonates (<28 >days), particularly those born prematurely or of low birth weight (g). Consumption of contaminated powdered infant formula (PIF) has been epidemiologically linked with cases of infection. Contamination can occur during the manufacturing process or during postmanufacture reconstitution of formula. Development of rapid, sensitive and specific detection methods will facilitate manufacturers efforts to reduce the occurrence of E. sakazakii in the final powdered product. Furthermore, since PIF …