bluuebunny/crossref_metadata_2025_split huggingface dataset:
Starting and Maintaining Monosiga brevicollis Cultures
Authors: King Nicole , Young Susan L. , Abedin Monika , Carr Martin , Leadbeater Barry S.C. 
Published: February 2009

INTRODUCTIONChoanoflagellates are heterotrophic nanoflagellates: small, colorless protozoa that are present in marine and freshwater environments as well as in hydrated soils. Because they are the closest living relatives of the metazoa, the study of their cell biology and genomes promises to provide new insights into metazoan ancestry and origins. Most, if not all, choanoflagellates are heterotrophs that prey on bacteria. Thus, all choanoflagellate media provide nutrition for bacteria, which are in turn consumed by the choanoflagellates. If a culture is axenic or has low bacterial content, it can be supplemented with a specific bacterial strain that has been grown separately. On the other hand, if a culture already contains a well-established flora of bacteria, it can be cocultured with the choanoflagellate isolate. In either case, it is common to enrich the medium with an organic extract, such as liver extract, cereal grass infusion, or a mixture of proteose peptone and yeast extract. This protocol describes how to start cultures of the marine choanoflagellate species, Monosiga brevicollis, from frozen stocks. These cultures can then be maintained and expanded in preparation for DNA or RNA isolation or cell biological assays.
Basics of Photoactivation
Authors: Ellis-Davies Graham C.R. 
Published: February 2009

INTRODUCTIONSpecific molecular interactions control cellular function. The photorelease of caged compounds (nucleotides, neurotransmitters, peptides, second messengers, proteins, etc.) can be used to control these interactions in living cells. Caged compounds are biological effector molecules whose active functionality has been chemically masked with a photoremovable protecting group. Illumination produces a concentration jump from the caged molecule. This article discusses the basic principles underlying photoactivation, the properties of caging chromophores and commercially available caged compounds, and practical considerations for their effective use.
Effects of ketoconazole and carbamazepine on lapatinib pharmacokinetics in healthy subjects
Authors: Smith Deborah A. , Koch Kevin M. , Arya Nikita , Bowen Carolyn J. , Herendeen Jill M , Beelen Andrew 
Published: February 2009

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT• Lapatinib is an orally administered tyrosine kinase inhibitor indicated for use in combination with capecitabine to treat advanced or metastatic breast cancers that overexpress ErbB2 in patients previously treated with anthracyclines, taxanes and trastuzumab.• In vitro studies have suggested that lapatinib is metabolized primarily by CYP3A4, that it is a substrate of the efflux transporter ABCB1, and that it is a modest inhibitor of both CYP3A4 and ABCB1.• However, no data regarding thein vivometabolism of lapatinib have as of yet been reported.WHAT THIS STUDY ADDS• Thein vivopharmacokinetics of lapatinib in healthy subjects was determined in the presence of a potent inhibitor (ketoconazole) or inducer (carbamazepine) of CYP3A4.• The results indicated that systemic exposure to lapatinib was significantly altered by inhibition or induction of CYP3A4.• Thus, dose adjustments may be required when lapatinib is administered orally concomitantly with drugs that potently alter CYP3A4 activity.AIMSTo characterize the impact of potent CYP3A4 inhibition and induction on lapatinib pharmacokinetics.METHODSTwo studies were conducted in healthy subjects. One study examined the effect of ketoconazole 200 mg b.i.d. for 7 days on a single 100‐mg dose of lapatinib in 22 healthy subjects. The other study examined the effect of carbamazepine titrated up to 200 mg b.i.d. over 20 days on a single 250‐mg dose of lapatinib in 24 healthy subjects.RESULTSKetoconazole altered lapatinib AUC,Cmaxand half‐life, with geometric mean [95% confidence interval (CI)] increases of 3.57‐fold (3.07, 4.15), 2.14‐fold (1.74, 2.64) and 1.66‐fold (1.50, 1.84), respectively, but had no effect on absorption rate. Carbamazepine altered lapatinib AUC,Cmaxand absorption rate, with geometric mean (95% CI) decreases of 72% (68, 77), 59% (49, 66) and 28% (4, 46), respectively, but had no effect on half‐life.CONCLUSIONSSystemic exposure to lapatinib was significantly altered by potent inhibition and induction of CYP3A4. Dose adjustments may be required when lapatinib is administered with orally administered drugs that potently alter the activity of this enzyme.
Large increase of the use of psycho‐stimulants among youth in the Netherlands between 1996 and 2006
Authors: Trip Anne‐Marie , Visser Sipke T. , Kalverdijk Luuk J. , De Jong‐van den Berg Lolkje T. W. 
Published: February 2009

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT? • In the USA psycho‐stimulant use has increased rapidly in the 1990s and stabilized around 2000.• This study describes the prevalence of psycho‐stimulant use between1996 and 2006 in the Netherlands. WHAT THIS STUDY ADDS • The prevalence of psycho‐stimulant use among youth in the Netherlands has increased more than eightfold in the period 1996–2006, but in 2006 it is still below the prevalence in the USA.AIM To describe the use of psycho‐stimulants in the Netherlands between 1996 and 2006 in children and adolescents, and in relation to age and sex.METHODS With the pharmacy prescription database the IADB.nl, yearly prevalences of psycho‐stimulants per 1000 children were calculated, as was the length of psycho‐stimulant use with Kaplan–Meier method in SPSS 12.0.RESULTS Psycho‐stimulant use increased in boys (0–19) from 4.5‰ in 1996 to 31.1‰ in 2006 and for girls from 0.7 to 8.1‰, respectively. The largest increase was among boys aged 10–19 years. There is a trend towards prescribing the sustained release preparation of methylphenidate (Concerta).CONCLUSIONS In the Netherlands a large increase in psycho‐stimulants use is observed. However, in the Netherlands the prevalence ratio male/female declined from 6.4 in 1996 to 3.8 in 2006.
Time‐dependent interactions of the hypotensive effects of sildenafil citrate and sublingual glyceryl trinitrate
Authors: Oliver James J. , Kerr Debra M. , Webb David J. 
Published: February 2009

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Co‐administration of inhibitors of phosphodiesterase type 5 with organic nitrates can cause profound hypotension.• For this reason, it is recommended that sildenafil and organic nitrates are not administered within 24 h of one another.• However, the time course of the interaction between sildenafil and sublingual glyceryl trinitrate (GTN) has not previously been investigated. WHAT THIS STUDY ADDS • In men with angina there is an interaction between oral sildenafil and sublingual GTN for ≥8 h, but from 6 h this interaction is not more than additive.• These data may be helpful to clinicians who are considering the use of GTN in patients presenting with angina who have received sildenafil within 24 h.AIM To investigate the time course of the hypotensive interaction between sildenafil and glyceryl trinitrate (GTN).METHODS Two double‐blind, placebo‐controlled, randomized, crossover studies were performed. Subjects were challenged with sublingual GTN 400 µg at different times after oral sildenafil 100 mg. After each GTN challenge frequent measures of blood pressure (BP) were made. In the first study GTN was given 1–48 h after sildenafil/placebo to 33 healthy men. In the second study GTN was given 1–8 h after sildenafil/placebo to 20 men with stable angina.RESULTS In healthy men there was a greater mean maximum reduction in BP with sildenafil/GTN than with placebo/GTN only at 1 h. In angina patients, there was a greater mean maximum reduction in BP with sildenafil/GTN than with placebo/GTN for up to 8 h. The mean (95% confidence interval) differences in maximum systolic BP reduction (mmHg) at 1, 4, 6 and 8 h were −16 (−12, −21), −12 (−4, −20), −6 (1, −12) and −9 (−3, −15), all P < 0.05 except at 6 h (NS). At 6 and 8 h the interaction was not more than additive, and hypotensive symptoms did not occur.CONCLUSIONS In men with angina there is an interaction on BP reduction between sildenafil and GTN for ≥ 8 h after sildenafil administration, but this is no more than additive from 6 h. These data may be helpful to clinicians who are considering the use of GTN in patients presenting with angina who have received sildenafil within 24 h.
Electrocardiogram changes and arrhythmias in venlafaxine overdose
Authors: Isbister Geoffrey K. 
Published: February 2009

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • The major clinical effects of venlafaxine overdose are seizures and serotonin toxicity.• There is controversy over the risk of cardiac toxicity in venlafaxine overdose. WHAT THIS STUDY ADDS • Venlafaxine overdose is unlikely to cause clinically significant cardiac toxicity, including QT prolongation or malignant arrhythmias, and the commonest cardiovascular effects are tachycardia and mild hypertension.• Massive ingestions >8 g may result in cardiac toxicity and patients should be observed carefully.AIMS To investigate serial electrocardiogram (ECG) parameters, haemodynamic changes and arrhythmias following venlafaxine overdose.METHODS The study included 369 venlafaxine overdoses in 273 patients presenting to a toxicology unit where an ECG was available. Demographic information, details of ingestion, haemodynamic effects [heart rate and blood pressure (BP)] and complications (arrhythmias and conduction defects) were obtained. ECG parameters (QT, QRS) were measured manually and analysed by visual inspection, including plotting QT–HR pairs on a QT nomogram.RESULTS The median ingested dose was 1500 mg [interquartile range (IQR) 600–3000 mg; range 75–13 500 mg). Tachycardia occurred in 54% and mild hypertension (systolic BP >140 mmHg) in 40%. Severe hypertension (systolic BP >180 mmHg) and hypotension (systolic BP <90 mmHg) occurred in 3% and 5%, respectively. No arrhythmias occurred based on continuous telemetry, and conduction defects were found in only seven of 369 admissions; five of these conduction defects were pre‐existing abnormalities. In 22 admissions [6%, 95% confidence interval (CI) 4–10] there was an abnormal QT–HR pair, with larger doses being more likely to be associated with an abnormal QT. The median maximum QRS width was 85 ms (IQR 80–90 ms; range 70–145 ms) and the QRS was greater than 120 ms in only 24 admissions (7%, 95% CI 4–10).CONCLUSIONS Venlafaxine overdose causes only minor abnormalities in the QT and QRS intervals, unlikely to be associated with major arrhythmias, except possibly with large doses.
Increase in tumour-infiltrating lymphocytes with regulatory T cell immunophenotypes and reduced ζ-chain expression in nasopharyngeal carcinoma patients
Authors: Yip W K , Abdullah M A , Yusoff S M , Seow H F 
Published: February 2009

Summary
The pathological significance of the mechanisms of tumour immune-evasion and/or immunosuppression, such as loss of T cell signalling and increase in regulatory T cells (Tregs), has not been well established in the nasopharyngeal carcinoma (NPC) microenvironment. To evaluate the Treg immunophenotypes in tumour-infiltrating lymphocytes (TILs), we performed a double-enzymatic immunostaining for detection of forkhead box P3 (FoxP3) and other markers including CD4, CD8, and CD25 on 64 NPC and 36 non-malignant nasopharyngeal (NP) paraffin-embedded tissues. Expression of CD3ζ and CD3ε was also determined. The prevalence of CD4+FoxP3+ cells in CD4+ T cells and the ratio of FoxP3+/CD8+ were increased significantly in NPC compared with those in NP tissues (P &lt; 0·001 and P = 0·025 respectively). Moreover, the ratio of FoxP3+/CD25+FoxP3− in NPC was significantly lower than that in NP tissues (P = 0·005), suggesting an imbalance favouring activated phenotype of T cells in NPC. A significant negative correlation between the abundance of FoxP3+ and CD25+FoxP3− cells (P &lt; 0·001) was also identified. When histological types of NPC were considered, a lower ratio of FoxP3+/CD25+FoxP3− was found in non-keratinizing and undifferentiated carcinomas. Increased CD4+FoxP3+/CD4+ proportion and FoxP3+/CD8+ ratio were associated with keratinizing squamous cell carcinoma. A reduced expression of CD3ζ in TILs was found in 20·6% of the NPC tissues but none of the NP tissues. These data provide evidence for the imbalances of Treg and effector T cell phenotypes and down-regulation of signal-transducing molecules in TILs, supporting their role in suppression of immune response and immune evasion of NPC.
T cell senescence and contraction of T cell repertoire diversity in patients with chronic obstructive pulmonary disease
Authors: Lambers C , Hacker S , Posch M , Hoetzenecker K , Pollreisz A , Lichtenauer M , Klepetko W , Jan Ankersmit H 
Published: February 2009

SummaryPathogenetic mechanisms leading to chronic obstructive pulmonary disease (COPD) remain poorly understood. Because clonogenic T cells (CD4+CD28null) were shown to be increased in autoimmune diseases we hypothesized that CD4+CD28null T cells play a role in COPD. Here we describe that enhanced presence of CD4+CD28null cells is associated with impaired lung function. Sixty-four patients and controls were included. T cell phenotype was analysed using flow cytometry. Enzyme-linked immunosorbent assays were utilized to determine cytokines. Statistical evaluations were performed using non-parametric group comparisons and correlations. A logistic regression model was used to determine predictive values of CD4+CD28null in the diagnosis of COPD. Populations of CD4+ T cells lacking surface co-stimulatory CD28 were enlarged significantly in evaluated patients when compared with controls. Natural killer (NK)-like T cell receptors (CD94, 158) and intracellular perforin, granzyme B were increased in CD4+CD28null cells. Cytokine production after triggering of peripheral blood mononuclear cells (PBMCs) was elevated in patients at early disease stages. Receiver operating characteristic curve plotting revealed that presence of CD4+CD28null T cells has a diagnostic value. These CD4+CD28null T cells show increased expression of NK-like T cell receptors (CD94, 158) and intracellular perforin and granzyme B. Furthermore, triggering of PBMCs obtained from patients with mild COPD led to increased interferon-γ and tumour necrosis factor-α production in vitro compared with controls. Our finding of increased CD4+CD28null T cells in COPD indicates that chronic antigen exposure, e.g. through contents of smoke, leads to loss of CD28 and up-regulation of NK cell receptors expression on T cells in susceptible patients.
Ca2+ Affects Physicochemical and Conformational Changes of Threadfin Bream Myosin and Actin in a Setting Model
Authors: Hemung Bung‐Orn , Yongsawatdigul Jirawat 
Published: February 2009

ABSTRACTThe effect of Ca2+ on physicochemical and conformational changes of threadfin bream (TB) myosin and actin during setting at 25 and 40°C was investigated. Ca2+ ion at 10 to 100 mM induced the unfolding of myosin and actin as evident by an increase of surface hydrophobicity (So ANS) at 40 °C. Total SH groups also decreased with an increased Ca2+ concentration, suggesting that Ca2+ promoted the formation of disulfide bonds during setting at 40 °C. Both hydrophobic interactions and disulfide linkages were involved in formation of myosin aggregates at 40 °C and were enhanced by addition of 10 to 100 mM Ca2+. Myosin Ca‐ATPase activity decreased when Ca2+ was greater than 50 mM, indicating conformational changes of myosin head. Circular dichroism spectra demonstrated that Ca2+ reduced the α‐helical content of myosin and actin incubated at either 25 or 40 °C. Ca2+ induced conformational changes of TB myosin and actin incubated at 40 °C to a greater extent than at 25 °C.
Validation of a High‐performance Liquid Chromatography‐Ultraviolet Method to Quantify Soy Sapogenols A and B in Soy Germs from Different Cultivars and in Soy Isoflavone‐Enriched Supplements
Authors: Hubert Jane , Berger Monique , Daydé Jean 
Published: February 2009

ABSTRACTAn increasing number of studies investigating the health effects of soy phytochemicals has led to the commercialization of many soy‐based products. Due to its particularly high concentration in many secondary metabolites, the use of soy germ as raw material is emerging for the processing of soy dietary supplements. However, the soybean seeds and germs do not exhibit the same major phytochemical profiles. This is particularly the case for soy saponins. Due to their structural diversity, the analysis of each individual soy saponin remains difficult. In this study, the total amount of these health‐protective phytochemicals was determined through the quantification of their aglucon precursors, soy sapogenols A and B. A simple and rapid analytical method was developed using high‐performance liquid chromatography coupled with an ultraviolet detection. The within‐day and between‐day variabilities of total soy sapogenol concentration were 7.3% and 10.9% in the whole seed and 3.3% and 4.7% in the germ, respectively. The total soy sapogenol contents investigated among the germs from 43 cultivars ranged from 32.8 μmol/g to 63.1 μmol/g. High amounts of soy saponins were also observed in several soy‐based dietary supplements, from 5.5 μmol/g to 107.8 μmol/g, with an A/B ratio varying from 0.3 to 8.6, showing large differences between the raw materials and concentration process used. These results indicate that these compounds have to be clearly determined when discussing the biological activity of dietary supplements issued from soy.
Lipid Oxidation in Microsomal Fraction of Squid Muscle (Loligo peali)
Authors: Thanonkaew Amonrat , Benjakul Soottawat , Visessanguan Wonnop , Decker Eric A. 
Published: February 2009

ABSTRACTFrozen squid is susceptible to both lipid oxidation and yellow/brown discoloration during frozen storage. The involvement of lipid oxidation in the microsomal fraction of squid muscle on oxidative rancidity and discoloration was investigated using iron and either enzymatic or non‐enzymatic redox cycling pathways. Lipid oxidation was measured by thiobarbituric acid‐reactive substances (TBARS), and color changes were measured spectrophotometrically using an integrating sphere. The lipid oxidation was not observed in the squid microsomes in the presence of Fe3+ and β‐nicotinamide adenine dinucleotide disodium salt (NADH) or β‐nicotinamide adenine dinucleotide phosphate, reduced (NADPH), suggesting that the enzymatic redox cycling pathway was not active. Iron‐promoted TBARS formation was observed in the non‐enzymatic pathway when ascorbic acid was used as a reducing compound. Non‐enzymatic lipid oxidation increased with increasing temperature (4 °C to 37 °C), iron (0 to 100 μM), and ascorbic acid (0 to 200 μM) concentrations. As lipid oxidation in the microsomes or isolated microsomal lipids increased, color changes were observed as could be seen by an increase in b* values (yellowness) and a decrease in a* (redness) values. The ability of iron and ascorbate to promote both lipid oxidation and pigment formation in the microsomal fraction suggests that this pathway could be responsible for quality deterioration of squid muscle during storage.
Stability of α‐Linolenic Acid and Secoisolariciresinol Diglucoside in Flaxseed‐Fortified Macaroni
Authors: Hall Clifford A. , Manthey Frank A. , Lee Robert E. , Niehaus Mary 
Published: February 2009

ABSTRACTResearch was conducted to determine the stability of secoisolariciresinol diglucoside (SDG) and α‐linolenic acid (ALA) in flaxseed‐fortified macaroni. Macaroni was fortified with whole ground flaxseed (GWF) at levels of 10% to 20% and then dried under low temperature (LT, 40°C), high temperature (HT, 70°C), or ultrahigh temperature (UHT, 90°C). Macaroni was also fortified with 15% ground hull (GHF) or steam‐treated whole ground flaxseed (GSWF) and dried under UHT. The dried macaroni was stored for 32 wk under ambient conditions. Approximately 80% to 95% of the SDG was recovered, indicating that SDG was stable during the 32‐wk storage period. Total lipid and ALA levels in all flaxseed macaroni treatments remained unchanged throughout the 32‐wk storage. This observation was consistent across the drying conditions and flaxseed addition levels. Conjugated diene (CD) values indicated that macaroni fortified with GWF did not oxidize significantly during the 32‐wk storage for the macaroni dried under HT or UHT. However, a significant increase (P <0.05) in CD values for macaroni containing 10% and 20% flaxseed and dried using LT was observed at the 32‐wk storage period. Headspace volatile concentrations did increase over the storage period for macaroni containing GWF, but the increase was not significant. Significant increases (P < 0.05) in oxidation were found by 24 wk in GHF‐ and GSWF‐fortified macaroni. GWF macaroni dried at UHT, HT, or LT could be used as a way to improve our dietary consumption of ALA and SDG. However, use of steam as a method to inactivate unwanted enzyme activity is not recommended.
Detection of Fecal Contamination on Cantaloupes Using Hyperspectral Fluorescence Imagery
Authors: Vargas Angela M. , Kim Moon S. , Tao Yang , Lefcourt Alan M. , Chen Yud‐Ren , LUO Yaguang , SONG Yoonseok , Buchanan Robert 
Published: February 2009

ABSTRACTTo determine whether detection of fecal contamination on cantaloupes is possible using fluorescence imaging, hyperspectral images of cantaloupes artificially contaminated with a range of diluted bovine feces were acquired from 425 to 774 nm in responses to ultraviolet‐A (320 to 400 nm) excitation. Evaluation of images at emission peak wavelengths indicated that 675 nm exhibited the greatest contrast between feces contaminated and untreated surface areas. Two‐band ratios compared with the single‐band images enhanced the contrast between the feces contaminated spots and untreated cantaloupe surfaces. The 595/655‐nm, 655/520‐nm, and 555/655‐nm ratio images provided relatively high detection rates ranging from 79% to 96% across all feces dilutions. However, both single band and ratio methods showed a number of false positives caused by such features as scarred tissues on cantaloupes. Principal component analysis (PCA) was performed using the entire hyperspectral images data; 2nd and 5th principal component (PC) image exhibited differential responses between feces spots and false positives. The combined use of the 2 PC images demonstrated the detection of feces spots (for example, minimum level of 16‐μg/mL dry fecal matter) with minimal false positives. Based on the PC weighing coefficients, the dominant wavelengths were 465, 487, 531, 607, 643, and 688 nm. This research demonstrated the potential of multispectral‐based fluorescence imaging for online applications for detection of fecal contamination on cantaloupes.
Effects of High Pressure on Texture and Microstructure of Sea Bass (Dicentrarchus labrax L.) Fillets
Authors: Chéret Romuald , Chapleau Nicolas , Delbarre‐Ladrat Christine , Verrez‐Bagnis Véronique , Lamballerie Marie de 
Published: February 2009

ABSTRACTHigh pressure is an innovative non‐thermal food‐preservation technology. We studied the effect of high‐pressure treatment up to 500 MPa for 5 min on physical characteristics of sea bass fillets after 0, 7, and 14 d of refrigerated storage. Color results exhibited an increase of lightness and a slight change of hue, which might be imperceptible in cooked fish. High‐pressure treatment induced a decrease of exudation and water‐holding capacity. Pressure treatment above 300 MPa provoked higher fish hardness after storage than in untreated sample, proving the ability of high pressure to improve textural quality of chilled, stored fish fillet. These assessments were corroborated with microstructure observations. We showed that high‐pressure treatment at 500 MPa allowed, after 7 d of storage, a total aerobic count equivalent to that of untreated fresh fish fillet to be obtained. Thus, high pressure might be considered to be a technology able to improve safety and textural quality of fresh fish fillets.