bluuebunny/crossref_metadata_2025 huggingface dataset:
Condition‐dependent mate choice and a reproductive disadvantage for MHC‐divergent male tiger salamanders
Authors: BOS DAVID H. , WILLIAMS ROD N. , GOPURENKO DAVID , BULUT ZAFER , DEWOODY J. ANDREW
Published: June 2009

Major histocompatibility complex (MHC) alleles likely have adaptive value because of overdominance, in which case MHC heterozygous individuals have increased fitness relative to homozygotes. Because of this potential benefit, the evolution of sexual reproduction between MHC‐divergent individuals (i.e. negative assortative mating, NAM) may be favoured. However, the strongest evidence for MHC‐based NAM comes from inbred animals, and context‐dependent mating preferences have rarely been evaluated although they often occur in nature. We assessed the extent MHC‐based mating preferences among wild tiger salamanders (Ambystoma tigrinum) using multiple molecular approaches. We genotyped 102 adults and 864 larvae from 36 breeding trials at both microsatellite and MHC loci. Parentage analysis revealed that reproductive success among males was positively associated with increased tail length and that with respect to the focal female, MHC‐similar males sired a significantly higher number of offspring than more dissimilar males. This trend was consistent, even under context‐dependent scenarios that favour traditional MHC‐based NAM. These results suggest that the most MHC‐divergent males may be at a reproductive disadvantage in pairwise breeding trials. Our data add to a growing body of evidence that suggests where it exists, MHC‐based choice is probably dynamic and mediated by many factors that vary in the wild, notably signals from other indicator traits and by the quality and quantity of potential mates.
Avascular osteonecrosis after treatment of SARS: a 3‐year longitudinal study
Authors: Lv Hui , De Vlas Sake J. , Liu Wei , Wang Tian‐Bao , Cao Zhao‐Yang , Li Chun‐Peng , Cao Wu‐Chun , Richardus Jan Hendrik
Published: June 2009

Objective  To investigate the relationship between avascular osteonecrosis (AVN) and corticosteroid treatment given to patients with severe acute respiratory syndrome (SARS).

Methods  Longitudinal study of 71 former SARS patients (mainly health care workers) who had been treated with corticosteroids, with an observation time of 36 months. Magnetic resonance images (MRI) and X‐rays of hips, knees, shoulders, ankles and wrists were taken as part of the post‐SARS follow‐up assessments.

Results  Thirty‐nine per cent developed AVN of the hips within 3–4 months after starting treatment. Two more cases of hip necrosis were seen after 1 year and another 11 cases of AVN were diagnosed after 3 years, one with hip necrosis and 10 with necrosis in other joints. In total, 58% of the cohort had developed AVN after 3 years of observation. The sole factor explaining AVN in the hip was the total dose of corticosteroids received.

Conclusion  The use of corticosteroids in SARS has been debated; opinions conflict about whether the immediate benefits in terms of saving lives compensate for the adverse effects, including AVN.
High level of natural variation in a groundnut (Arachis hypogaea L.) germplasm collection assayed by selected informative SSR markers
Authors: Varshney R. K. , Mahendar T. , Aruna R. , Nigam S. N. , Neelima K. , Vadez V. , Hoisington D. A.
Published: June 2009

The ability to identify genetic variation is indispensable for effective management and use of genetic resources in crop breeding. Genetic variation among 189 groundnut (Arachis hypogaea L.) accessions comprising landraces, cultivars, a mutant, advanced breeding lines and others (unknown genetic background) representing 29 countries and 10 geographical regions was assessed at 25 microsatellite or simple sequence repeat loci. A high number of alleles (265) were detected in the range of 3 (Ah1TC6G09) to 20 (Ah1TC11H06) with an average of 10.6 alleles per locus. The polymorphism information content value at these loci varied from 0.38 (Ah1TC6G09) to 0.88 (Ah1TC11H06) with an average of 0.70. A total of 59 unique alleles and 127 rare alleles were detected at almost all the loci assayed. Cluster analysis grouped 189 accessions into four clusters. In general, genotypes of South America and South Asia showed high level of diversity. Extraordinary level of natural genetic variation reported here provides opportunities to the groundnut community to make better decisions and define suitable strategies for harnessing the genetic variation in groundnut breeding.
The relation of arterial stiffness with intrauterine growth retardation
Authors: Levent Ertürk , Atik Tahir , Darcan Şükran , Ülger Zülal , Gökşen Damla , Özyürek A. Ruhi
Published: June 2009

Background:  Much epidemiological evidence has linked low birthweight with late cardiovascular risk. Intrauterine growth retardation (IUGR) is associated with the increased risk of cardiovascular disease in adult life; it is unclear whether the relationship is present at younger ages. We evaluated whether abdominal aortic stiffness was altered in patients with IUGR (born at term with birthweight small for gestational age) in younger ages.

Methods:  Thirty‐two (24 girls and eight boys) IUGR children aged 8.77 ± 2.05 years were enrolled in the study. The birthweight was traced from the medical records. Their gestational ages were 38.9 ± 0.85 weeks and birthweights 2130 ± 198 g, respectively. Thirty‐one healthy subjects who had normal gestational age and birthweight, matched for age and sex were recruited as a control group. Aortic strain, pressure strain elastic modulus (Ep), and normalized Ep and aortic distensibility were measured by a sphygmomanometer and transthoracic echocardiography in all subjects from the abdominal aorta.

Results:  There was no statistically significant difference between the study and the control groups in sex, mean age, body mass index, lipid profile, leptin, insulin‐like growth factor‐1 or insulin‐like growth factor binding protein 3. In IUGR children, aortic strain (0.201 ± 0.027 vs 0.254 ± 0.031, P < 0.001) and aortic distensibility (1.08 ± 0.19 vs 1.42 ± 0.24, P < 0.001) were significantly lower compared with the control group. However Ep (188 ± 36.2 vs 146 ± 27.1, P < 0.001) and normalized Ep (2.97 ± 0.40 vs 2.1 ± 0.39, P < 0.001) were significantly higher in IUGR patients.

Conclusions:  This study demonstrates that abdominal aortic stiffness is increased in IUGR patients. These data suggest that prenatal events could be related to cardiovascular risk in later life.
Effect of ezetimibe/simvastatin compared with atorvastatin on lipoprotein subclasses in patients with type 2 diabetes and hypercholesterolaemia
Authors: Tomassini J. E. , Mazzone T. , Goldberg R. B. , Guyton J. R. , Weinstock R. S. , Polis A. , Jensen E. , Tershakovec A. M.
Published: June 2009

Aim: To evaluate the effects of the usual starting and next higher doses of ezetimibe/simvastatin and atorvastatin on the cholesterol content of lipoprotein subclasses in patients with type 2 diabetes and hypercholesterolaemia.

Methods: This post hoc analysis compared the effects of treatment with ezetimibe/simvastatin 10/20 mg vs. atorvastatin 10 and 20 mg/day and ezetimibe/simvastatin 10/40 mg/day vs. atorvastatin 40 mg/day on the cholesterol content of lipoprotein subclasses in the modified intent‐to‐treat (mITT) population (n = 1013) and in subgroups of patients with triglyceride (TG) levels <200 mg/dl (n = 600) and ≥200 mg/dl (2.6 mmol/l) (n = 413).

Results: Ezetimibe/simvastatin significantly reduced low‐density lipoprotein cholesterol (LDL‐C) subclasses LDL1‐C, LDL2‐C and LDL3‐C; real LDL‐C (LDL‐Cr); intermediate‐density lipoprotein cholesterol (IDL‐C), IDL1‐C, IDL2‐C; very low‐density lipoprotein cholesterol (VLDL‐C), VLDL3‐C; and remnant‐like lipoprotein cholesterol (RLP‐C) from baseline more than atorvastatin at all dose comparisons (p < 0.01) in the mITT population. Significant improvements were also observed in high‐density lipoprotein cholesterol (HDL‐C) subclass HDL3‐C at the ezetimibe/simvastatin 10/20 mg vs. atorvastatin 20 mg and highest dose comparisons (p < 0.001) and in VLDL1 + 2‐C at the lowest and highest dose comparisons (p < 0.001). Changes in LDL4‐C and LDL‐C subclass patterns (A, B and I) were comparable for both treatments. Generally, similar results were observed for patients with TG levels <200 and ≥200 mg/dl (2.3 mmol). For both treatments, notable differences between TG subgroups were that patients with elevated TGs had smaller reductions in LDL2‐C, slightly smaller decreases in all IDL subclasses and greater decreases in all VLDL‐C subclasses than those with lower TG levels. Frequency of pattern B was also reduced more in patients with higher TGs for both treatments.

Conclusions: Ezetimibe/simvastatin reduced the cholesterol content of most lipoprotein subclasses from baseline with generally similar efficacy in patients with low and high TGs. Despite the different mechanism of action of ezetimibe, the response to ezetimibe/simvastatin and atorvastatin treatment related to these lipoprotein subclasses was generally consistent with the overall effects of these therapies on the major lipid/lipoprotein classes. The clinical significance of these results awaits further study.
Non‐understanding as a heuristic to hypothesizing cultural models: A meta‐oriented sociolinguistic strategy1
Authors: Yamaguchi Masataka
Published: June 2009

This article is concerned with the development of an analytic strategy to construct U.S. cultural models of war and terrorism, which are ‘mediatized’ or significantly shaped by the media. Central to that strategy are repair cues to non‐understanding as heuristics in intercultural encounters. These are applied to an inherently mediatized discursive ‘reality’ of war and terrorism. Theoretically, I synthesize sociolinguistic and anthropological perspectives into a ‘meta‐oriented sociolinguistics’, which analytically focuses on the meta‐dimension of discourse. The strategy is applied to a text on war and terrorism from theNew York Times, to demonstrate its utility. Furthermore, I provide implications for enhancing validity in the ethnography of mediatized discourse. Specific to the findings of this article, I suggest that corpus studies of media discourse should be conducted on the metadiscursive keywordskamikaze,surprise attacks,Pearl Harbor, and9/11in particular temporal frames.
Temporal changes to spatially stratified waterbird communities of the Coorong, South Australia: implications for the management of heterogenous wetlands
Authors: Paton D. C. , Rogers D. J. , Hill B. M. , Bailey C. P. , Ziembicki M.
Published: June 2009

The Coorong, South Australia, is a globally significant wetland system, listed in the Ramsar Convention under a number of different criteria, including its importance to waterbird populations. Based on annual waterbird censuses conducted between 2000 and 2007, spatiotemporal analyses revealed that significant differences in waterbird community structure exist along the length of the Coorong. This spatial diversity in community structure was also found to be temporally consistent over this 8‐year period. The abundance of the most numerically dominant bird species, such as red‐necked stint Calidris ruficollis and grey teal Anas gracilis, explained much of this spatial variation. However, comparisons between data collected for the Coorong south lagoon in 1985 and 2000–2007 show that dramatic changes in these waterbird communities have occurred over longer periods of time, with 23 of the 27 most common species having declined in this period by at least 30%. The Coorong still regularly supports globally important populations (>1% of global population) of nine waterbird taxa, including three Palearctic shorebirds, confirming its Ramsar status. The functional links between the overutilized Murray‐Darling basin river system and the Coorong are discussed.
Degeneration of cultured cortical neurons following prolonged inactivation: molecular mechanisms
Authors: Schonfeld‐Dado Eldi , Fishbein Ianai , Segal Menahem
Published: June 2009

Networks of neurons express persistent spontaneous network activity when maintained in dissociated cultures. Prolonged blockade of the spontaneous activity with tetrodotoxin (TTX) causes the eventual death of the neurons. In this study, we investigated some molecular mechanisms that may underlie the activity‐suppressed slow degeneration of cortical neurons in culture. Already after 3–4 days of exposure to TTX, well before the neurons die, they began to express markers that lead to their eventual death, 7–10 days later. There was a reduction in glutamate receptor (GluR2) expression, a persistent increase in intracellular calcium concentration, activation of calpain, and an increase in spectrin breakdown products. At this point, blockade of GluR2‐lacking GluR1 or calpain (either with a selective antagonist or through the natural regulator of calpain, calpastatin), protected cells from the toxic action of TTX. Subsequently, mitochondria lost their normal elongated shape as well as their membrane potential. Eventually, neurons activated caspase 3 and PUMA (p53 up‐regulated modulator ofapoptosis), hallmarks of neuronal apoptosis, and died. These experiments will lead to a better understanding of slow neuronal death, typical of neurodegenerative diseases.
Transition novelty moderates daters' cortisol responses when talking about marriage
Authors: LOVING TIMOTHY J. , GLEASON MARCI E. J. , POPE MARK T.
Published: June 2009

Nonmarital couples' salivary cortisol responses during a likelihood of marriage discussion were assessed. Sixty‐eight couple members (34 couples) in the United States independently indicated the extent to which they had experience thinking about and talking about marriage to their current partners (i.e., marriage novelty). Couples subsequently jointly graphed their chance of marriage to each other over the course of their relationship histories. Increased levels of marriage novelty predicted heightened cortisol reactivity to the joint discussion relative to cortisol responses of couple members for whom the idea of marriage was less novel. These results highlight the impact simply discussing transitions can have on individuals' physiological responses, and add to the expanding literature concerning the link between nonmarital romances and biological outcomes.
Liver stiffness measurement using FibroScan® is influenced by serum total bilirubin in acute hepatitis
Authors: Kim Seung Up , Han Kwang‐Hyub , Park Jun Yong , Ahn Sang Hoon , Chung Moon Jae , Chon Chae Yoon , Choi Eun Hee , Kim Do Young
Published: June 2009

Background: Liver stiffness measurement (LSM) using FibroScan® is accepted as a highly reproducible and accurate technique for assessment of liver fibrosis. However, several studies have indicated that the LSM value can be significantly influenced by major changes in aminotransferases in patients with chronic viral hepatitis and LSM is unreliable for diagnosing underlying liver cirrhosis in patients with acute liver damage. We aimed to determine biochemical factors influencing the LSM value in patients with acute hepatitis.

Methods: From July to December 2007, a total of 60 patients with acute hepatitis of varying aetiologies were recruited prospectively. LSM and biochemical tests were performed at diagnosis and recovery from acute hepatitis.

Results: The mean age of the patients (38 men and 22 women) was 40.7±15.4 years. The aetiology of acute hepatitis included hepatitis A virus in 31 patients, drug induced in 19 and hepatitis B virus in 10. The mean LSM value was 19.6 kPa at diagnosis and 15.9 kPa at recovery. Correlation analysis showed that the LSM value at diagnosis was significantly associated with platelet count (P=0.023), alanine aminotransferase (P=0.045), albumin (P<0.001), total bilirubin (P=0.004) and prothrombin time (P=0.005). However, additional correlation analysis between the changes in LSM value and biochemical factors from diagnosis to recovery showed that the change in total bilirubin was found to be the only factor associated with the change in the LSM value (P<0.001).

Conclusions: Our data suggest that the LSM value might be influenced by serum total bilirubin in patients with acute hepatitis without pre‐existing underlying chronic liver disease.
Experimental models of hepatic encephalopathy: ISHEN guidelines
Authors: Butterworth Roger F. , Norenberg Michael D. , Felipo Vicente , Ferenci Peter , Albrecht Jan , Blei Andres T. ,   Members of the ISHEN Commission on Experimental Models of HE]
Published: June 2009

Objectives of the International Society for Hepatic Encephalopathy and Nitrogen Metabolism Commission were to identify well‐characterized animal models of hepatic encephalopathy (HE) and to highlight areas of animal modelling of the disorder that are in need of development. Features essential to HE modelling were identified. The best‐characterized animal models of HE in acute liver failure, the so‐called Type A HE, were found to be the hepatic devascularized rat and the rat with thioacetamide‐induced toxic liver injury. In case of chronic liver failure, surgical models in the rat involving end‐to‐side portacaval anastomosis or bile duct ligation were considered to best model minimal/mild (Type B) HE. Unfortunately, at this time, there are no satisfactory animal models of Type C HE resulting from end‐stage alcoholic liver disease or viral hepatitis, the most common aetiologies encountered in patients. The commission highlighted the urgent need for such models and of improved models of HE in chronic liver failure in general as well as a need for models of post‐transplant neuropsychiatric disorders. Studies of HE pathophysiology at the cellular and molecular level continue to benefit from in vitro and or ex vivo models involving brain slices or exposure of cultured cells (principally cultured astrocytes) to toxins such as ammonia, manganese and pro‐inflammatory cytokines. More attention could be paid in the future to in vitro models involving the neurovascular unit, microglia and neuronal co‐cultures in relation to HE pathogenesis.
Current Status of Hemofiltration
Authors: Henderson Lee W.
Published: June 2009

Hemofiltration is reviewed from the standpoint of the technical and clinical state of the art. It is a new technique and, at present, commercially available equipment is limited. Clinical experience suggests that hemofiltration results in easier attainment of salt and water balance and that control of hypertension is improved. The nomenclature used to describe convective solute and water removal alone and in conjunction with dialysis is outlined.
Dialysis of Schizophrenics Weird and Novel Applications of Dialysis, Hemofiltration, Hemoperfusion and Peritoneal Dialysis: Witchcraft?
Authors: Kolff Willem J.
Published: June 2009

Dialysis resulted in a remarkable cure of 17 out of 24 patients treated in Gainesville, Florida and Louisville, Kentucky. The diagnosis of these patients was schizophrenia. However, the diagnosis of schizophrenia is often controversial. It is also very difficult to eliminate the placebo effect. Leucine5‐endorphin was found in the dialyzing fluid of ten of these patients. Its concentration was Reported to be parallel to the clinical improvement. The finding of leucine5‐endorphin has, as yet, not been confirmed in other laboratories. Cats injected with concentrate of the dialysate into the ventricles of their brains exhibited symptoms reminiscent of schizophrenia. Cats injected with a synthetic preparation of leucine5‐endorphin exhibited the same symptoms. As yet, these experiments have not been repeated in other laboratories. If, indeed, leucine5‐endorphin or a similar substance is removed with dialysis, then it can be calculated that ultrafiltration would be more effective than dialysis and peritoneal lavage might be quite effective for its removal. The double blind studies which have been started will be fraught with difficulties and will be very time consuming. On the other hand, verification of the finding of endorphin or another substance would be relatively quick since a large number of patients could be given one diagnostic ultrafiltration each. The ultrafiltrate might be tested chemically and biologically. If, indeed, a substance were found but not in normal people, then the presence of such a substance might, in turn, help to establish the diagnosis of schizophrenia.
Low‐Dose Heparin in Routine Hemodialysis Monitored by Activated Partial Thromboplastin Time
Authors: Shapiro Warren B. , Faubert Pierre F. , Porush Jerome G. , Chou Shyan‐yih
Published: June 2009

To evaluate the use of the activated partial thromboplastin time (APTT), as measured by the Coag‐A‐Mate semi‐automatic unit, in lowering the dosage of heparin in stable chronic hemodialysis patients, four protocols for anticoagulation were utilized. Ten patients were dialyzed five times with each protocol. In protocol I, clotting time was performed baseline, 2 and 4 hours and in protocol II, baseline and every 30 minutes, with heparin administered by bolus to keep the clotting time at 2–2% times normal. In protocols III and IV the APTT was performed every 30 minutes, with heparin given by bolus in protocol III and infusion in protocol IV, to keep the APTT 11/2‐‐2 times normal. Protocol I required 6000±543 U of heparin with the dose decreasing significantly to 3694 ± 158 U in protocol II, 2634 ± 139 U in protocol III and 2013±117 U in protocol IV (P<0.05 ‐<0.001). Three episodes of clotting occurred, one in protocol III and two in protocol IV. There was no bleeding, and clearances of urea, creatinine, phosphate and uric acid at 1 and 5 hours were similar in all protocols. APTT, as measured by the Coag‐A‐Mate unit, provides a simple means of lowering heparin requirements in routine dialysis patients.
Stochasticity in Physiologically Based Kinetics Models: Implications for Cancer Risk Assessment
Authors: Péry Alexandre Roger Raymond , Bois Frederic Yves
Published: June 2009

In case of low‐dose exposure to a substance, its concentration in cells is likely to be stochastic. Assessing the consequences of this stochasticity in toxicological risk assessment requires the coupling of macroscopic dynamics models describing whole‐body kinetics with microscopic tools designed to simulate stochasticity. In this article, we propose an approach to approximate stochastic cell concentration of butadiene in the cells of diverse organs. We adapted the dynamics equations of a physiologically based pharmacokinetic (PBPK) model and used a stochastic simulator for the system of equations that we derived. We then coupled kinetics simulations with a deterministic hockey stick model of carcinogenicity. Stochasticity induced substantial modifications relative to dose‐response curve, compared with the deterministic situation. In particular, there was nonlinearity in the response and the stochastic apparent threshold was lower than the deterministic one. The approach that we developed could easily be extended to other biological studies to assess the influence of stochasticity at macroscopic scale for compound dynamics at the cell level.
Immediate restoration/loading of immediately placed single implants: is it an effective bimodal approach?
Authors: Atieh Momen A. , Payne Alan G. T. , Duncan Warwick J. , Cullinan Mary P.
Published: June 2009

Objective: To compare systematically the survival and radiographic marginal bone level changes of two immediate implant protocols in the aesthetic region; immediate single implant restoration/loading in extraction sockets (the bimodal approach) compared with the same in healed sites.

Material and methods: A literature search of electronic databases, Cochrane Oral Health Group's Trials Register, National Research Register, conference proceedings and abstracts was performed without language restriction up to 1 August 2008. Hand searching included several dental journals and authors were contacted for missing information. Controlled trials that compared immediate restoration/loading of single implants placed in extraction sites with those placed in healed sites were selected. The meta‐analysis was prepared according to the guidelines of the Quality of Reporting of Meta‐analyses statement. The data were analysed using RevMan version 5.0 software. A fixed effects model was chosen with standardized mean differences for continuous data, and risk ratios for dichotomous data with 95% confidence intervals.

Results: Ten studies with 629 implants were included. Immediate single implant restoration/loading in extraction sockets in the aesthetic zone was associated with significantly higher risk of implant failure (risk ratio of 3.62, 95% confidence interval 1.15–11.45, P=0.03). However, the bimodal approach showed favourable marginal bone changes after 1 year.

Conclusion: The review and meta‐analysis supported the potential advantages offered by this bimodal approach, but indicated a higher risk when compared with immediate restoration/loading in healed ridges. Further long‐term, well‐conducted, randomized‐controlled studies are needed to confirm the validity of this treatment option.
Transport of Benzo[α]pyrene in the Dually Perfused Human Placenta Perfusion Model: Effect of Albumin in the Perfusion Medium
Authors: Mathiesen Line , Rytting Erik , Mose Tina , Knudsen Lisbeth E.
Published: June 2009

Abstract:  Transport of benzo[α]pyrene (BaP) across the placenta was examined because it is a ubiquitous and highly carcinogenic substance found in tobacco smoke, polluted air and certain foods. Foetal exposure to this substance is highly relevant but is difficult to estimate. The human placenta is unique compared to other species; since it is available without major ethical obstacles, we have used the human placenta perfusion model to study transport from mother to foetus. Placentas were donated after births at Rigshospitalet in Copenhagen from pregnant mothers who signed an informed consent. BaP is lipophilic and studies using cell culture medium in 6‐hr placenta perfusions showed minimal transport through the placenta. To increase the solubility of BaP in perfusion medium and to increase physiological relevance, perfusions were also performed with albumin added to the perfusion medium [2 and 30 mg/ml bovine serum albumin (BSA) and 30 mg/ml human serum albumin (HSA)]. The addition of albumin resulted in increased transfer of BaP from maternal to foetal reservoirs. The transfer was even higher in the presence of an HSA formulation containing acetyltryptophanate and caprylate, resulting in a foetal–maternal concentration (FM) ratio of 0.71 ± 0.10 after 3 hr and 0.78 ± 0.11 after 6 hr, whereas the FM ratio in perfusions without albumin was only 0.05 ± 0.03 after 6 hr of perfusion. Less BaP accumulated in placental tissue in perfusions with added albumin. This shows that transplacental transport of the pro‐carcinogenic substance BaP occurs, and emphasizes the importance of adding physiological concentrations of albumin when studying the transport of lipophilic substances.
DEVELOPMENT OF MULTIPLEX PCR ASSAYS FOR DETECTION OF ANTIMICROBIAL RESISTANCE GENES IN ESCHERICHIA COLI AND ENTEROCOCCI
Authors: SIANGLUM WIPAWADEE , KITTINIYOM KANOKWAN , SRIMANOTE POTJANEE , WONGLUMSOM WIJIT
Published: June 2009

Two multiplex polymerase chain reaction (mPCR) assays were developed for simultaneous detection of antimicrobial resistance genes in Escherichia coli and enterococci. Oligonucleotide primer sets were designed and formulated. Primer set I was used to detect resistance genes including tetracycline (tetM and tetA), chloramphenicol (cat1 and cmlA) and sulfonamide (sul1), in 20 E. coli isolates. Primer set II was designed to identify three target genes including tetM, tetL and ermB of tetracycline and erythromycin resistance genes, respectively. In the final volume of 25 µL, optimal concentrations of mPCR primer for investigation of E. coli and enterococci resistance genes were 0.1, 0.4, 0.2, 0.4 and 0.2 µM of tetA, tetM, cat1, cmlA and sul1, and 0.2, 0.2 and 0.1 µM of tetM, tetL and ermB, respectively. The optimal annealing temperatures were 51 and 57C to detect all expected resistance genes of E. coli and enterococci, respectively. The amplicon sizes ranged from 171 to 847 bp for E. coli and 171 to 505 bp for enterococci, differing by at least 83 bp to simplify gel electrophoretic separation. The correlation between dot blot hybridization and mPCR results were investigated. Two of the 20 E. coli isolates showed positive results by mPCR and negative results by hybridization assay. The same results were observed with two different methods among 20 enterococci isolates indicating that the targets were amplified efficiently. The developed mPCR assay is a simple, rapid and useful method for genotyping detection of multiple resistance genes in single reaction.

PRACTICAL APPLICATIONS

Multiplex polymerase chain reaction (mPCR) can allow the detection of various antimicrobial resistance genes in one PCR reaction tube. The technique is fast and reliable for rapid screening of multiple resistance genes. In this study, we focused on the simultaneous detection of five and three most commonly found resistance genes in Escherichia coli and enterococci isolates, respectively. Our research has shown that the mPCR method could be expanded to include the determination of other antibiotic resistance genes of interest. The system described here can decrease PCR reagent cost by multiple resistance genes detection in each reaction tube. The high throughput and cost‐effective mPCR system developed in this study could provide a powerful tool for more accurate detection of various antimicrobial resistance genes associated with E. coli and enterococci isolates.
SEROLOGICAL ATTRACTION OF NONTOXIC EGG COMPONENT TO STAPHYLOCOCCAL ANTI‐ENTEROTOXIN
Authors: BENNETT REGINALD W.
Published: June 2009

Raw whole liquid and dried eggs which were purported to contain staphylococcal enterotoxin were analyzed by a number of enzyme‐linked immunosorbent assay (ELISA)‐based methods. The initial evaluation was to establish whether the purported positive ELISA reactions were a result of toxin‐anti‐enterotoxin serological activity. A secondary consideration was to determine whether the putative protein occurred in the yolk and/or white portions of the eggs. A manual polyvalent detection system, manual monovalent ELISA and an automated polyvalent enzyme‐linked fluorescent immunoassay were used to investigate this component in eggs. The ELISA results were instantaneous and showed strong positive reactions (false positives) with the manual and automated polyvalent systems, suggesting nonspecific binding of the egg‐reactive component to one or more staphylococcal enterotoxin antibodies. Further analysis with the monovalent ELISA showed false‐positive reactions when egg extracts were tested separately for enterotoxins A–E. The putative protein from fertilized eggs had caused false‐positive reactions and the eggs did not contain preformed staphylococcal enterotoxin.

PRACTICAL APPLICATIONS

The analysis of raw whole liquid and dried eggs for staphylococcal enterotoxin must be performed with circumspection when applying serological systems which use whole antibody, as the resulting positive reaction could be a false‐positive reaction due to a nontoxic component in eggs which reacts with the staphylococcal anti‐enterotoxins.
RAPID DETECTION OF LISTERIA MONOCYTOGENES IN GROUND TURKEY BY IMMUNOMAGNETIC SEPARATION AND POLYMERASE CHAIN REACTION
Authors: AYAZ N.D. , EROL I.
Published: June 2009

The aim of this study was to determine the prevalence of Listeria monocytogenes in packaged fresh ground turkey in Turkey using immunomagnetic separation (IMS) as a selective enrichment step in method and polymerase chain reaction (PCR). A total of 180 ground turkey samples were collected during a 1‐year period. Thirty‐two (17.7%) of the samples contained L. monocytogenes, 24 (13.3%) contained Listeria innocua, 7 (3.8%) had Listeria ivanovii and 5 (2.7%) had Listeria seeligeri by means of IMS‐based cultivation method. A PCR assay was performed, based on hlyA gene‐specific primers. In all L. monocytogenes isolates, hlyA gene was confirmed, indicating that the correlation between IMS‐based cultivation and PCR methods was 100%. The results suggest that the prevalence of L. monocytogenes in ground turkey is relatively high in Turkey and that ground turkey should be produced under appropriate hygienic and technological conditions for the prevention of public health hazards.

PRACTICAL APPLICATIONS

Using fast and reliable methods to detect and identify foodborne pathogenic bacteria, including Listeria monocytogenes, is important to detect the risk of contaminated product and protect public health. In some ways it is time‐consuming to isolate and identify the pathogenic microorganisms from food products using conventional techniques. Different methods or techniques can be used both for redounding the isolation chance and to gain time for this purpose. Immunomagnetic separation (IMS) and polymerase chain reaction (PCR) techniques are effective and rapid methods for separation, detection and confirmation of Listeria spp. from foods. In this study rapid, specific and sensitive IMS method was used to determine the prevalence of L. monocytogenes in fresh ground turkey and PCR technique was used for the verification of the L. monocytogenes isolates.
Microbial Inactivation Kinetics in Soymilk during Continuous Flow High‐Pressure Throttling
Authors: Sharma Vijendra , Singh Rakesh K. , Toledo Romeo T.
Published: June 2009

ABSTRACT:  The thermal resistance of Clostridium sporogenes PA 3679 ATCC 7955 was determined in soymilk (pH 7) and 0.1% peptone water (pH 7) by the capillary tube method. In the continuous flow high‐pressure throttling, the temperature of soymilk increased due to instantaneous pressure release and the additional heat was supplied by a heat exchanger to achieve the set temperature. The soymilk was immediately cooled after a short preset hold time to below 40 °C. A significant increase in the heat resistance was observed in C. sporogenes spores when heated in soymilk in comparison to 0.1% peptone water. The D121‐value for spores in soymilk was approximately 3‐folds higher than peptone water. The z‐value was also much higher in soymilk as compared to that in 0.1% peptone water. Continuous flow high‐pressure throttling (HPT) from 207 or 276 MPa to atmospheric pressure reduced the microbial populations in inoculated soymilk up to 6 log cycles when the holding times were 10.4, 15.6, and 20.8 s and the process temperatures were 85, 121, 133, and 145 °C, respectively. The sporicidal effect increased as the operating pressure, time, and temperature were increased. More injured spores were found at 207 MPa than at 276 MPa, indicating that lower pressure caused cell injury whereas high pressure caused cell death.
The Arterial Pulse Wave and Vascular Compliance
Authors: Noon Joseph P.
Published: June 2009

For just over 1 century, we have relied on cuff sphygmomanometry to measure blood pressure at a peripheral (brachial) site. This measurement provides a quantitative snapshot of hemodynamic activity at 1 part of the arterial tree. Because the heart and brain are exposed to central (aortic) and not peripheral (brachial) pressure, it might be timely for nurses to start looking at alternative techniques to provide more meaningful information on central hemodynamics. The noninvasive technique of applanation tonometry allows such measurements to be performed quickly in the nursing clinic. By analyzing the pulse wave and calculating pulse wave velocity, the technique also assesses arterial “stiffness.” This method of cardiovascular assessment further enables nurses to monitor the central effects of antihypertensive, lipid lowering, and other drug therapy over time.
FUZZY MULTIPLE OBJECTIVE PROGRAMMING IN AN INTERVAL PIECEWISE REGRESSION MODEL
Authors: YU JING-RUNG , TZENG GWO-HSHIUNG
Published: June 2009

This study proposes fuzzy multiple objective programming to determine the measure of fitness and the number of change-points in an interval piecewise regression model. To increase the measure of fitness, Tanaka and Lee proposed a conceptual procedure, which is a heuristic approach and becomes complicated for determining the proper polynomial. Therefore, a multiple objective approach is adopted to obtain a compromise solution among three objectives — maximizing the measure of fitness, minimizing the number of change-points and minimizing the width to obtain the interval regression models. By using the proposed method, a better measure of fitness can be obtained. Two numerical examples are used as demonstrations to illustrate our approach in more detail.
THE GENERALIZED BIPARABOLIC DISTRIBUTION
Authors: GARCÍA CATALINA BEATRIZ GARCÍA , PÉREZ JOSÉ GARCÍA , RAMBAUD SALVADOR CRUZ
Published: June 2009

Beta distributions have been applied in a variety of fields in part due to its similarity to the normal distribution while allowing for a larger flexibility of skewness and kurtosis coverage when compared to the normal distribution. In spite of these advantages, the two-sided power (TSP) distribution was presented as an alternative to the beta distribution to address some of its short-comings, such as not possessing a cumulative density function (cdf) in a closed form and a difficulty with the interpretation of its parameters. The introduction of the biparabolic distribution and its generalization in this paper may be thought of in the same vein. Similar to the TSP distribution, the generalized biparabolic (GBP) distribution also possesses a closed form cdf, but contrary to the TSP distribution its density function is smooth at the mode. We shall demonstrate, using a moment ratio diagram comparison, that the GBP distribution provides for a larger flexibility in skewness and kurtosis coverage than the beta distribution when restricted to the unimodal domain. A detailed mean-variance comparison of GBP, beta and TSP distributions is presented in a Project Evaluation and Review Technique (PERT) context. Finally, we shall fit a GBP distribution to an example of financial European stock data and demonstrate a favorable fit of the GBP distribution compared to other distributions that have traditionally been used in that field, including the beta distribution.
Mitochondrial Evolution and Functions in Malaria Parasites
Authors: Vaidya Akhil B. , Mather Michael W.
Published: June 2009

Mitochondria in malaria parasites have some unusual evolutionary and functional features. The drastic reduction in the size of their mitochondrial genome, encoding just three proteins, appears to have originated at the point of divergence of dinoflagellates and apicomplexan parasites from ciliates and may have accompanied the acquisition of plastids by the former. Unusual translational machinery as revealed by the highly fragmented mitochondrial ribosomal RNA genes also appears to have originated at this deflection point. Some of the biochemical properties of malarial mitochondria also appear to be unconventional. Although tricarboxylic acid cycle enzymes are encoded by the genome, they do not appear to be involved in the full oxidation of glucose to fuel mitochondrial ATP synthesis in the blood stages of malaria parasites. A critical role of the mitochondrial electron transport chain appears to be to serve pyrimidine biosynthesis. In spite of their minimal nature, Plasmodium mitochondria are attractive targets for antimalarial drugs.
Pricing Urban Congestion
Authors: Parry Ian W.H.
Published: June 2009

This paper reviews literature on the optimal design of pricing policies to reduce urban automobile congestion. The implications of a range of complicating factors are considered; these include traffic bottlenecks, constraints on which roads and freeway lanes in the road network can be priced, driver heterogeneity, private toll operators, other externalities besides congestion, and interactions between congestion taxes and the broader fiscal system. I also briefly discuss the incidence of congestion taxes and experience with this policy in the United States and elsewhere. Although the economics literature on congestion pricing has advanced considerably over the past 20 years, research is still needed on the empirical measurement of second-best efficient tolls for urban centers and whether alternative design features have substantial implications for efficiency. More research is also needed on the design of schemes to promote feasibility by compensating adversely affected groups with minimal loss in economic efficiency.
Peculiar flow patterns of RBCs suspended in viscous fluids and perfused through a narrow tube (25 μm)
Authors: Sakai Hiromi , Sato Atsushi , Okuda Naoto , Takeoka Shinji , Maeda Nobuji , Tsuchida Eishun
Published: June 2009

Red blood cells (RBCs) generally deform to adopt a parachute-like, torpedo-like, or other configuration to align and flow through a capillary that is narrower than their major axis. As described herein, even in a narrow tube (25 μm) with diameter much larger than that of a capillary, flowing RBCs at 1 mm/s align axially and deform to a paraboloid shape in a viscous Newtonian fluid (505 kDa dextran medium) with viscosity of 23.4–57.1 mPa·s. A high-speed digital camera image showed that the silhouette of the tip of RBCs fits a parabola, unlike the shape of RBCs in capillaries, because of the longer distance of the RBC-free layer between the tube wall and the RBC surface (∼8.8 μm). However, when RBCs are suspended in a “non-Newtonian” viscous fluid (liposome-40 kDa dextran medium) with a shear-thinning profile, they migrate toward the tube wall to avoid the axial lining, as “near-wall-excess,” which is usually observed for platelets. This migration results from the presence of flocculated liposomes at the tube center. In contrast, such near-wall excess was not observed when RBCs were suspended in a nearly Newtonian liposome-albumin medium. Such unusual flow patterns of RBCs would be explainable by the principle; a larger particle tends to flow near the centerline, and a small one tends to go to the wall to flow with least resistance. However, we visualized for the first time the complete axial aligning and near-wall excess of RBCs in the noncapillary size tube in some extreme conditions.
Subcellular movement and expression of HSP27, αB-crystallin, and HSP70 after two bouts of eccentric exercise in humans
Authors: Paulsen G. , Lauritzen F. , Bayer M. L. , Kalhovde J. M. , Ugelstad I. , Owe S. G. , Hallén J. , Bergersen L. H. , Raastad T.
Published: June 2009

The aims of this study were to investigate the sarcomeric accumulation and expression of heat shock proteins (HSPs) after two bouts of maximal eccentric exercise. Twenty-four subjects performed two bouts of 70 maximal voluntary eccentric actions using the elbow flexors in one arm. The bouts were separated by 3 wk. The changes in concentric (60°/s) and isometric (90°) force-generating capacity were monitored for 9 days after each bout, and biopsies were taken 1 and 48 h and 4 and 7 days after bout 1 and 1 and 48 h after bout 2. The content of HSP27, αB-crystallin, HSP70, and desmin in the cytosolic and cytoskeleton/myofibrillar fractions of homogenized muscle samples was determined by immunoassays, and the cellular and subcellular localization of the HSPs in the myofibrillar structure was analyzed by conventional and confocal immunofluorescence microscopy and quantitative electron microscopy. The force-generating capacity was reduced by ∼50% and did not recover completely during the 3 wk following bout 1. After bout 2, the subjects recovered within 4 days. The HSP levels increased in the cytosolic fraction after bout 1, especially HSP70 (∼300% 2–7 days after exercise). Increased levels of HSP27, αB-crystallin, and HSP70 were found in the cytoskeletal/myofibrillar fraction after both bouts, despite reduced damage after bout 2. At the ultrastructural level, HSP27 and αB-crystallin accumulated in Z-disks, in intermediate desmin-like structures (αB-crystallin), and in areas of myofibrillar disruption. In conclusion, HSP27 and αB-crystallin accumulated in myofibrillar structures, especially in the Z-disks and the intermediate structures (desmin). The function of the small HSPs is possibly to stabilize and protect the myofibrillar structures during and after unaccustomed eccentric exercise. The large amount of HSP27, αB-crystallin, and HSP70 in the cytoskeletal/myofibrillar fraction after a repeated bout of exercise suggests a protective role as part of the repeated-bout effect.
NADPH oxidase-derived reactive oxygen species in skeletal muscle modulates the exercise pressor reflex
Authors: Wang Han-Jun , Pan Yan-Xia , Wang Wei-Zhong , Zucker Irving H. , Wang Wei
Published: June 2009

Muscle metabolic by-products during exercise, such as K+, lactic acid, ATP, H+, and phosphate, are well established to be involved in the reflex cardiovascular response to static muscle contraction. However, the role of muscle reactive oxygen species (ROS), a metabolic by-product during muscle contraction, in the exercise pressor reflex (EPR) has not been investigated in detail. In the present study, we evaluated the role of muscle ROS in the EPR in a decerebrate rat model. We hypothesized that muscle NADPH oxidase-derived ROS contributes to sensitization of the EPR. Thus the rise in blood pressure and heart rate in response to a 30-s static contraction induced by electrical stimulation of L4/L5 ventral roots was compared before and after hindlimb arterial infusion of the redox agents: diethyldithiocarbamate, a superoxide dismutase inhibitor; the superoxide dismutase mimetic 4-hydroxy-2,2,6,6-tetramethyl piperidine 1-oxyl (tempol); the free radical scavenger dimethylthiourea; a NADPH oxidase inhibitor, apocynin; and a xanthine oxidase inhibitor, allopurinol. The EPR-induced pressor response was augmented after treatment with diethyldithiocarbamate and was attenuated after treatment with tempol, dimethylthiourea, and apocynin. Treatment with allopurinol did not affect the EPR function. None of the drug's affected the EPR heart rate response. In addition, neither the pressor response to electrical stimulation of the central end of dorsal roots, nor femoral blood flow was affected by any treatment. These data suggest that NADPH oxidase-derived muscle ROS plays an excitatory role in the EPR control of blood pressure.
Effect of exercise training on resistance arteries in rats with chronic NOS inhibition
Authors: Kuru Oktay , Şentürk Ümit Kemal , Koçer Günnur , Özdem Sadi , Başkurt Oǧuz K. , Çetin Arzu , Yeşilkaya Akin , Gündüz Filiz
Published: June 2009

Regular exercise has blood pressure-lowering effects, as shown in different types of experimental hypertension models in rats, including the nitric oxide synthase (NOS) inhibition model. We aimed to investigate possible mechanisms implicated in the exercise effect by evaluating the vasoreactivity of resistance arteries. Exercise effects on agonist-induced vasodilatory responses and flow-mediated dilation were evaluated in vessel segments of the rat chronic NOS inhibition model. Normotensive and hypertensive rats were subjected to swimming exercise (1 h/day, 5 days/wk, 6 wk), while rats in other sedentary and hypertensive groups did not. Hypertension was induced by oral administration of the nonselective NOS inhibitor l-NAME (25 mg/kg day) for 6 wk. Systolic blood pressure, as measured by the tail-cuff method, was significantly decreased by the training protocol in exercising hypertensive rats. The vasoreactivity of resistance arteries was evaluated by both wire and pressure myography studies. An impaired nitric oxide-mediated relaxation pathway in untrained hypertensive rats led to decreased relaxation responses in vessels with intact endothelium. Exercise training significantly improved the responses to acetylcholine and flow-mediated dilation in exercise-trained hypertensive rats in parallel with a decrease in blood pressure. On the other hand contraction (norepinephrine and KCl) and relaxation (sodium nitroprusside) responses of vascular smooth muscle were not different between the groups. Vascular endothelial NOS protein expression was found to be increased in both exercising groups. In conclusion, these results revealed evidence of an increased role of the nitric oxide-dependent relaxation pathway in exercising hypertensive rats.