bluuebunny/crossref_metadata_2025 huggingface dataset:
Evidence for a photoprotective function of low‐temperature‐induced anthocyanin accumulation in apple and pear peel
Authors: Steyn Willem J. , Wand Stephanie J.E. , Jacobs Gerard , Rosecrance Richard C. , Roberts Stephanie C.
Published: April 2009

The light requirement and low‐temperature stimulation of anthocyanin synthesis in peel of apple (Malus domestica) and pears (Pyrus communis) and the presence of anthocyanins in immature fruits are not congruent with a visual function in dispersal. We hypothesized that anthocyanins afford photoprotection to peel during low‐temperature‐induced light stress and that the protection is not a fortuitous side‐effect of light absorption by anthocyanin. The extent of photoinhibition at harvest and after light stress treatment in pear cultivars differing in redness decreased with increasing red color on the sun‐exposed sides of fruits. Green‐shaded sides of the pears showed comparable levels of photoinhibition indicating that pears did not differ in their inherent photosensitivity. Apple and pear peel show considerable short‐term fluctuation in redness in response to temperature, with red color increasing rapidly in response to low temperature and just as quickly fading in response to high temperature. Briefly, shading pears and apples during cold conditions for 2 days reduced the accumulation of anthocyanin and increased the photosensitivity of peel. Subsequent shading during warm conditions did not affect the accumulation of anthocyanin or the photosensitivity of peel indicating that the response at low temperature was not due to shade adaptation. The assessment of photosystem II (PSII) efficiency and quenching of chlorophyll fluorescence between 16 and 40°C indicated that ‘Forelle’ pear peel was particularly sensitive to photostress at low temperature. The photosynthetic system in mature ‘Forelle’ leaves was comparatively much less sensitive to light stress at low temperature. Results support the view that anthocyanins are adaptable light screens deployed to modulate light absorption in sensitive tissues such as fruit peel in response to environmental triggers such as cold front snaps.
The alternative oxidase, a tool for compensating cytochrome c oxidase deficiency in human cells
Authors: Dassa Emmanuel P. , Dufour Eric , Goncalves Sergio , Jacobs Howard T. , Rustin Pierre
Published: April 2009

In plants as well as in a number of micro‐organisms, and in several animal phyla, but not in mammals, the alternative oxidase (AOX) possibly by‐passes the cytochrome segment of the respiratory chain. The AOX is located at the inner surface of the inner mitochondrial membrane, being activated by over‐reduction of the quinone pool and accumulation of keto‐acids such as pyruvate. Since these conditions are frequently encountered in patients with mitochondrial diseases, we hypothesized that the expression of the ascidian Ciona intestinalis AOX might alleviate the consequences of a blockade of the cytochrome segment of the respiratory chain in human cells. We previously expressed the C. intestinalis AOX in human embryonic kidney (HEK 293‐T‐derived) cells conferring cyanide‐resistance to cell respiration without any detectable detrimental effect (Hakkaart et al. 2006). We have now expressed the AOX in human cultured fibroblasts either with a functional respiratory chain (foreskin immortalized fibroblasts, BJ1‐htert) or presenting a cytochrome c oxidase deficiency resulting from an impaired heme aa3 biogenesis. We used immortalized COX15‐deficient skin fibroblasts from a patient who died from an early fatal cardiomyopathy. We found that the expression of the AOX in these cells was well tolerated and corrected for the various consequences of the cytochrome c oxidase deficiency in COX15‐mutant cells, i.e. decreased cell respiration, glucose and pyruvate dependency. We thus validated our hypothesis that AOX could compensate for cytochrome c oxidase deficiency in human cells.
The impact of introduced predators on two threatened prey species: A case study from western New South Wales
Authors: Wheeler Robert , Priddel David
Published: May 2009

Summary  Since European settlement, many Australian mammals have become extinct; numerous others survive within substantially reduced ranges. Predation by the Red Fox (Vulpes vulpes) and House Cat (Felis catus) are two of the major drivers of this decline. The demise of Australia's native fauna continues, with ground‐nesting birds such as the Malleefowl (Leipoa ocellata) now being at greatest risk of extinction. In regions of Western Australia, this situation has been partially reversed through the broadscale control of the Fox and the re‐introduction of locally extinct species. In this paper, we review research undertaken on Yathong Nature Reserve (YNR) in western New South Wales to (i) evaluate current threats, and (ii) assess our ability to restore locally extinct species across this particular landscape. We conducted releases of both the Malleefowl and Brush‐tailed Bettong (Bettongia penicillata), two species that were once common in the region. Despite the potential for food resources to have been diminished by exotic herbivores, we found no evidence that food shortage was a limiting factor for either of the two species we released. Predation by the Fox was the greatest single cause of Malleefowl mortality. Localized, intensive ground baiting of the Fox was essentially ineffective in mitigating this threat, whereas broadscale aerial baiting substantially enhanced Malleefowl survival, at least during the first few years. Accordingly, thrice‐yearly aerial baiting for the Fox has been conducted on YNR since 1996. Despite this, and a long‐term restocking programme, the size of the Malleefowl population has not increased since aerial baiting began. The release of the Brush‐tailed Bettong into YNR in 2001 confirmed the effectiveness of the ongoing fox‐control programme but demonstrated the detrimental impact of another introduced predator – the Cat. We conclude that, while current management actions continue, the Fox is no longer a threat to wildlife on YNR, and suggest that the Cat is now the major impediment to both the recovery of depleted faunal populations (including the Malleefowl) and the restoration of locally extinct species (such as bettongs) within this landscape.
The politics of risk in the Philippines: comparing state and NGO perceptions of disaster management
Authors: Bankoff Greg , Hilhorst Dorothea
Published: May 2009

It is now generally appreciated that what constitutes vulnerability to one person is not necessarily perceived as such by the next. Different actors ‘see’ disasters as different types of events and as a result they prepare for, manage and record them in very different ways. This paper explores what different perceptions of vulnerability mean in terms of the understanding and practices of two significant sets of actors and stakeholders involved in disaster preparedness and management in the Philippines: the state and NGOs. Approaches to disaster are not just a function of people's perceptions of disaster risk but also of their understanding of the prevailing social order and social relations. Despite a shared vocabulary—which increasingly presents disasters as processes rather than events, takes a proactive rather than a reactive approach, and favours the inclusion of stakeholders rather than solely relying on technocratic management—different realities continue to make for different responses.
Wildland fire mitigation networks in the western United States
Authors: Wise Charles R. , McGuire Michael
Published: May 2009

Multiorganisational networks have become the primary vehicle through which disaster policy is designed and administered. Numerous case studies reveal their importance and the role they play in all phases of disaster management. This research emphasis on the description of coordination and collaboration lacks a descriptive framework, however, for examining the capabilities and potentialities of networks. This paper provides an overview of the network and disaster management literature and suggests six basic components of a network structural framework that can be used by researchers and practitioners. The framework is then applied to six wildland fire mitigation networks in the United States as a means of illustrating how such networks are actually configured. The results of the empirical research show that the capacity of the networks is mixed, with most lacking the ability to assess risk and evaluate their activities.
Debriefing with teachers after the Marmara earthquake: an evaluation study1
Authors: Şahin Nesrin Hisli , Batıgün Ayşegül Durak , Yılmaz Banu
Published: May 2009

The aim of this study was to evaluate the effectiveness of the debriefing meetings conducted after the 1999 earthquakes in Marmara, Turkey. The sample consisted of 265 teachers, 223 of whom attended the debriefing meetings. The personal satisfaction ratings of the teachers who attended the meetings revealed that they found the sessions satisfactory. The results of the comparison between those who reported that they benefited from the meetings and those who felt they did not indicated that the first group had lower scores on all of the psychopathology measures. A comparison between 42 teachers who did not attend the meetings and a randomly chosen group of 45 teachers who did attend revealed that the two groups differed significantly in terms of their post‐traumatic stress symptom scores. The findings of the study suggest that, in general, the teachers' debriefing sessions were satisfactory.
Participation Bias, Durable Opinion Shifts and Sabotage through Withdrawal in Citizens' Juries
Authors: French Damien , Laver Michael
Published: May 2009

We analyse a citizens' jury experiment held in Dublin on the ‘hot-button’ issue of waste incineration. The jury was a random sample drawn from the 2002 Irish Election Study (IES), and we compare jurors to non-jurors in the 2002 IES, and in 2003 and 2004 panel studies. Large opinion shifts were observed in a representative jury; these shifts remained observable nine months later. However, as a direct consequence of our choice of a contested issue, the jurors' verdict was framed by the unwillingness of key stakeholders to participate. Stakeholders who expect to be on the ‘losing’ side, including public representatives and officials, may obstruct and delegitimise citizens' juries by withholding participation. This informal gatekeeping power undermines the potential of citizens' juries to empower citizens.
THE HERMENEUTICS OF INTER‐FAITH RELATIONS: RETRIEVING MODERATION AND PLURALISM AS UNIVERSAL PRINCIPLES IN QUR'ANIC EXEGESES
Authors: Afsaruddin Asma
Published: May 2009

This article discusses the exegeses of two Qur'anic verses: Qur'an 2:143, which describes righteous Muslims as constituting a “middle/moderate community” (umma wasat) and Qur'an 5:66, which similarly describes righteous Jews and Christians as constituting a “balanced/moderate community” (umma muqtasida). Taken together, these verses clearly suggest that it is subscription to some common standard of righteousness and ethical conduct that determines the salvific nature of a religious community and not the denominational label it chooses to wear. Such a perspective offers the possibility of formulating universal principles of ethical and moral conduct, which may contribute to the formation of a genuinely pluralist global society today. Through a close study of Qur'anic exegeses of these verses from the late first/seventh century to modern times, I retrieve some of the most prevalent Muslim understandings of “moderation” through time and dwell on their contemporary implications.
Identifying the woes of the cotton textile industry in Bengal: tales of the nineteenth century
Authors: RAY INDRAJIT
Published: May 2009

This article seeks to answer three basic questions about the nineteenth‐century cotton textile industry in Bengal that still remain unresolved in the literature; namely, when did the industry begin to decay, what was the extent of its decay during the early nineteenth century, and what were the factors that led to this? In the absence of data on production, this article seeks to settle the debate on the basis of the industry's market performance and its consumption of raw materials. It contests the prevailing hypothesis that the industry's perpetual decline started in the late eighteenth or the early nineteenth century. Instead, it is argued that the decline started around the mid‐1820s. The pace of its decline was, however, slow though steady at the beginning, but reached crisis point by 1860, when around 563,000 workers lost their jobs. Regarding the extent of its decay, this article concludes that the industry was diminished by about 28 per cent by the mid‐1800s. However, it survived in the high‐end and low‐end domestic markets. Evidence is also gathered in favour of the hypothesis that, although British discriminatory policies undoubtedly depressed the industry's export outlet, its decay is better explained by technological innovations in Great Britain.
Choice, Culture and the Politics of Belonging: The Emerging Law of Forced and Arranged Marriage
Authors: Enright Máiréad
Published: May 2009

The article discusses recent legal and policy initiatives aimed at preventing forced marriage, placing them in the broader context of the exclusionary governance of British Muslim cultural difference. It argues that forced marriage is understood almost entirely as a product of cultural difference. Thus, attempts to prevent forced marriage focus on the control of cultural pressures at the point of marriage. This near‐exclusive focus on culture has two consequences for women. First, inadequate attention is paid to the social and economic problems which intersect with and aggravate cultural factors restricting women's marital choice. Second, this problematisation of culture has generated paternalistic legislation with the consequence that young women who wish to follow cultural practice and fully consent to an arranged marriage may be prevented from marrying as they choose.
Interpreting the Threshold Criteria under section 31(2) of the Children Act 1989 – the House of Lords decision in Re B1
Authors: Cobley Cathy , Lowe Nigel
Published: May 2009

The casenote considers the decision in Re B which confirms the threshold criteria in establishing the likelihood of future harm under section 31(2) of the Children Act 1989 and clarifies the civil standard of proof.
The Prevalence of Headache With Emphasis on Tension-Type Headache in Rural Tanzania: A Community-Based Study
Authors: Winkler AS , Stelzhammer B , Kerschbaumsteiner K , Meindl M , Dent W , Kaaya J , Matuja W , Schmutzhard E
Published: May 2009

The aim of the study was to assess the prevalence of headache with special attention to tension-type headache (TTH) in a rural area in northern Tanzania. A door-to-door study was performed using a standardized and validated questionnaire. A total of 7412 participants were screened. The total headache prevalence during the past year was 12.1%; the overall 1-year prevalence of TTH was 7%; 5% reported episodic TTH and 0.4% chronic TTH. Borderline cases (International Headache Society code 2.3) were described in 1.6%. The prevalence of headache was highest in the 41-50-year-old group in women and in the 61+ age group in men. This is the first account of the prevalence of TTH in a rural Tanzanian population, and shows that headache in general and, more specifically, TTH are prevalent disorders that deserve attention. However, the prevalence of primary headache seems to be lower than in Western countries.
Neurophysiological investigations of hepatic encephalopathy: ISHEN practice guidelines
Authors: Guerit Jean‐Michel , Amantini Aldo , Fischer Catherine , Kaplan Peter W. , Mecarelli Oriano , Schnitzler Alfons , Ubiali Emilio , Amodio Piero ,   the members of the ISHEN commission on Neurophysiological Investigations
Published: May 2009

By studying neuronal activity through neuronal electrogenesis, neurophysiological investigations provide a functional assessment of the nervous system and, therefore, has been used for quantitative assessment and follow‐up of hepatic encephalopathy (HE). The different clinical neurophysiological approaches can be classified depending on the function to explore and their sensitivity to HE. The reliable techniques are those that reflect cortical function, i.e., cognitive‐evoked potentials (EPs) (P300 paradigm), electroencephalogram (EEG), visual EPs (latency>100 ms) and somatosensory EPs (SEPs) (latency between 25 and 100 ms). Short‐latency EPs (brainstem acoustic EPs, SEPs of a latency<25 ms) are in principle insensitive to HE, but can disclose brainstem conduction deficits due to oedema. SEPs and motor EPs can disclose myelopathies. Because of its parallelism to the clinical examination, clinical neurophysiology can complement the neurological examination: (i) to provide evidence of HE in patients who have normal consciousness; (ii) to rule out, at least under some conditions, disturbances of consciousness due to other causes (e.g. drug‐induced disturbances, non‐convulsive status epilepticus) with the reservation that the mildest degrees of encephalopathy might be associated with an EEG pattern similar to that induced by drugs; and (iii) to demonstrate the worsening or, conversely improvement, of HE in the follow‐up period.
Sintering and Mechanical Properties of Mullite‐Reinforced Boron Carbide Matrix Composite
Authors: Zuoguang Zhang , Mingchao Wang , Min Li , Zhijie Sun
Published: May 2009

In order to improve the mechanical properties of boron carbide (B4C) ceramic, a mullite‐reinforced B4C matrix ceramic with complete densification was fabricated via hot pressing for the first time. The dense sintering mechanism of mullite‐reinforced B4C ceramic was discussed through the phase and element analysis. A new dense sintering mechanism was found in which the diffusion of Si in mullite through the B4C matrix enhances the sintering of mullite‐reinforced B4C ceramics effectively. The mechanical properties and microstructure of the composite ceramics were investigated in contrast with monolithic B4C and one kind of commercial B4C ceramic. The flexural strength and fractural toughness of B4C with 3 vol% mullite addition reached 560 MPa and 3.33 MPa·m1/2, which is 154% and 96% higher than that of monolithic B4C, respectively.
High kallikrein‐related peptidase 6 in non‐small cell lung cancer cells: an indicator of tumour proliferation and poor prognosis
Authors: Nathalie Heuzé‐Vourc’h , Chris Planque , Serge Guyetant , Catherine Coco , Benjamin Brillet , Claire Blechet , Christelle Parent , Briollais Laurent , Pascale Reverdiau , Marie‐Lise Jourdan , Yves Courty
Published: May 2009

The human kallikrein‐related peptidases (KLK) are serine proteases whose concentrations are often abnormal in common human malignancies and contribute to neoplastic progression through multifaceted roles. However, little attention has been paid to their synthesis and involvement in the development and dissemination of lung cancer, the leading cause of cancer mortality worldwide. We have analysed the production of KLK6 in normal lung and tumour tissues from patients with non‐small cell lung cancer (NSCLC). KLK6 immunoreactivity was restricted to epithelial cells of the normal bronchi, but most of the cancer samples were moderately or highly immunoreactive, regardless of the histological subtype. In contrast, little or no KLK6 was detected in NSCLC cells. We have developed NSCLC lines expressing wild‐type KLK6 in order to investigate the role of KLK6 in lung cancer biology, and analysed its impact on proliferation. Ectopic KLK6 dramatically enhanced NSCLC cell growth and KLK6‐producing NSCLC cells had accelerated cell cycles, between the G1 and S phases. This was accompanied by a marked increase in cyclin E and decrease in p21. KLK6 production was also associated with enhanced synthesis of c‐Myc, which is known to promote cell‐cycle progression. Finally, examination of specimens from patients with NSCLC revealed that KLK6 mRNA is overexpressed in tumour tissue, and high KLK6 concentrations were associated with lower survival rates. We conclude that a high concentration of KLK6 is an indicator of tumour proliferation and an independent predictive factor in NSCLC.
A systematic review of the 5‐year survival and complication rates of implant‐supported single crowns
Authors: Jung Ronald E. , Pjetursson Bjarni E. , Glauser Roland , Zembic Anja , Zwahlen Marcel , Lang Niklaus P.
Published: May 2009

Objectives: The objective of this systematic review was to assess the 5‐year survival of implant‐supported single crowns (SCs) and to describe the incidence of biological and technical complications.

Methods: An electronic MEDLINE search complemented by manual searching was conducted to identify prospective and retrospective cohort studies on SCs with a mean follow‐up time of at least 5 years. Failure and complication rates were analyzed using random‐effects Poisson's regression models to obtain summary estimates of 5‐year proportions.

Results: Twenty‐six studies from an initial yield of 3601 titles were finally selected and data were extracted. In a meta‐analysis of these studies, survival of implants supporting SCs was 96.8% [95% confidence interval (CI): 95.9–97.6%] after 5 years. The survival rate of SCs supported by implants was 94.5% (95% CI: 92.5–95.9%) after 5 years of function. The survival rate of metal–ceramic crowns, 95.4% (95% CI: 93.6–96.7%), was significantly (P=0.005) higher than the survival rate, 91.2% (95% CI: 86.8–94.2%), of all‐ceramic crowns.

Peri‐implantitis and soft tissue complications occurred adjacent to 9.7% of the SCs and 6.3% of the implants had bone loss exceeding 2 mm over the 5‐year observation period. The cumulative incidence of implant fractures after 5 years was 0.14%. After 5 years, the cumulative incidence of screw or abutment loosening was 12.7% and 0.35% for screw or abutment fracture. For supra‐structure‐related complications, the cumulative incidence of ceramic or veneer fractures was 4.5%.

Conclusion: It can be concluded that after an observation period of 5 years, high survival rates for implants and implant‐supported SCs can be expected. However, biological and particularly technical complications are frequent.
Following the FateIn Vivoof COPI Vesicles GeneratedIn Vitro
Authors: Rutz Christoph , Satoh Ayano , Ronchi Paolo , Brügger Britta , Warren Graham , Wieland Felix T.
Published: April 2009

COPI vesicles are a class of transport carriers that function in the early secretory pathway. Their fate and function are still controversial. This includes their contribution to bidirectional transport within the Golgi apparatus and their role during cell division. Here we describe a method that should address several open questions about the fate and function of COPI vesiclesin vivo. To this end, fluorescently labeled COPI vesicles were generatedin vitrofrom isolated rat liver Golgi membranes, labeled with the fluorescent dyes Alexa‐488 or Alexa‐568. These vesicles appeared to be active and colocalized with endogenous Golgi membranes within 30 min after microinjection into mammalian cells. The COPI vesicle‐derived labeled membrane proteins could be classified into two types that behaved like endogenous proteins after Brefeldin A treatment.
Cerebral MRI findings in a cohort of ex‐preterm and control adolescents
Authors: Nagy Zoltan , Jónsson Baldvin
Published: May 2009

Aim: Newborn infants were entered between 1988 and 1993 into a prospective, long‐term, follow‐up study. We aimed to investigate how the outcome of preterm‐born individuals on cerebral magnetic resonance imaging (MRI) compared to that reported on similar cohorts internationally.

Methods: The 74 ex‐preterm (12.38–17.7 years, 51% girls) and 69 control participants (12.18–16.47 years, 53% girls) underwent a MRI examination on a 1.5T scanner. Two experienced neuroradiologists examined the T1‐ and T2‐weigthed images first independently and then in consensus without knowledge of group adherence.

Results: Only 21 (4 controls) of the 143 sets of scans showed any abnormalities. All but one of these were of mild extent. Among the ex‐preterm adolescents two showed only incidental findings while the other 15 had either gliosis or white matter loss. Eleven subjects had white matter loss, seven of which had no other abnormalities. Four subjects had gliosis, three of which had no other abnormalities. The extent, severity or frequency of injury was not related to being born small for gestational age.

Conclusion: Although the rate of structural abnormalities was higher in the group of adolescents born preterm, this rate was well below that reported from other centres around the world. We attribute this to the minimally invasive neonatal care and to different social structures in Sweden compared to that of other reports on similar cohorts.
A primary care provider’s guide to preventive and acute care management of adults and children with sickle cell disease
Authors: Pack‐Mabien Ardie , Haynes Johnson
Published: May 2009

Purpose: To familiarize primary care providers (PCPs) with the pathophysiological processes, diagnostic evaluation, and medical management of sickle hemoglobinopathies and their complications. Current standards of care, clinical research advances, and new treatment options will also be addressed to assist PCPs in the management of sickle cell disease (SCD).

Data sources: A selective search and review of the current literature on SCD and the authors’ experience.

Conclusions: Management of individuals with SCD is very complex, requiring a multidisciplinary approach that includes the patient or parent, PCP, specialist, nurse, and social worker. More patients living with SCD are relying on PCPs in nonspecialty practices for comprehensive disease management.

Implications for practice: Newborn screening detects new cases of SCD annually. The median life expectancy has more than doubled for individuals with sickle cell anemia. Healthcare providers are now in an era of increased routine screening, assessment, and management of chronic complications from this illness not previously seen in the care of adults with SCD.
Current understanding and management of dilated cardiomyopathy in Duchenne and Becker muscular dystrophy
Authors: Kaspar Rita Wen , Allen Hugh D. , Montanaro Federica
Published: May 2009

Purpose: To review the current understanding of the pathophysiology of dilated cardiomyopathy (DCM) in patients with Duchenne and Becker muscular dystrophies, assessment of cardiac dysfunction for these patients, and the recommended pharmacological treatment options and ongoing research directions.

Data sources: Reviews and original research articles from scholarly journals and books.

Conclusions: Duchenne and Becker muscular dystrophies are debilitating neuromuscular disorders, both caused by mutations in the dystrophin gene. Most patients develop DCM as part of the disease course; in fact, DCM is the leading cause of death among these patients. Cardiac surveillance, including routine monitoring of electrocardiograms, echocardiograms, and appropriate blood biomarkers, may detect early DCM development. Although previous studies have shown that early administration of cardiac medications may delay the development of DCM, current standard of care does not emphasize cardiac surveillance and timely treatment. This, in turn, limits clinicians, including advanced practice nurses, to be optimally engaged in providing the most aggressive and proactive patient care.

Implications for practice: Implementing a routine cardiac assessment and timely pharmacological treatment in primary or specialty care settings is highlighted as an important step to optimize cardiac health among patients with Duchenne and Becker muscular dystrophies.
Carbon payments as a safeguard for threatened tropical mammals
Authors: Venter Oscar , Meijaard Erik , Possingham Hugh , Dennis Rona , Sheil Douglas , Wich Serge , Hovani Lex , Wilson Kerrie
Published: May 2009

One reason for the rapid loss of species‐rich tropical forests is the high opportunity costs of forest protection. In Kalimantan (Indonesian Borneo), the expansion of high‐revenue oil palm (Elaeis guineensis) plantations currently threatens 3.3 million ha of forest. We estimate that payments for Reduced Emissions from Deforestation and forest Degradation (REDD) could offset the costs of stopping this deforestation at carbon prices of US$10–33 per tonne of CO2, or $2–16 per tonne if forest conservation targets only cost‐efficient areas. Forty globally threatened mammals are found within these planned plantations, including the Bornean orangutan (Pongo pygmaeus) and Borneo pygmy elephant (Elephas maximus borneensis). Cost‐efficient areas for emissions reductions also contain higher‐than‐average numbers of threatened mammals, indicating that there may be synergies between mitigating climate change and conserving biodiversity. While many policy and implementation issues need clarification, our economic assessment suggests that REDD could offer a financially realistic lifeline for Kalimantan's threatened mammals if it is included in future climate agreements.
Glutathione homeostasis in ventricular myocytes from rat hearts with chronic myocardial infarction
Authors: Li Shumin , Zheng Ming‐Qi , Rozanski George J.
Published: April 2009

The ubiquitous tripeptide glutathione (GSH) is an essential factor in many biological processes, thus its depletion has a major impact on cell function and survival. In this study, we examined regulation of GSH in cardiomyocytes under chronic oxidative stress elicited by myocardial infarction (MI). Cardiac dysfunction was induced in rats by coronary artery ligation, and experiments were conducted in myocytes isolated from non‐infarcted left ventricle and septum after 6–8 weeks. Fluorescence microscopy studies using the probe monochlorobimane showed that [GSH] in myocytes from post‐MI hearts was 42% less than in sham control hearts (P < 0.05). However, depleted GSH levels were normalized after 5–6 h by an insulin mimetic (bis‐peroxovanadium‐1,10‐phenanthroline, bpV(phen); 10 μmol l−1) or by exogenous pyruvate (5 mmol l−1). The increase in [GSH] by bpV(phen) was partly inhibited by buthionine sulphoximine (BSO; 50 μmol l−1), a blocker of GSH synthesis, and by 1,3‐bis‐(2‐chloroethyl)‐1‐nitrosourea (BCNU; 100 μmol l−1), an inhibitor of glutathione disulphide reductase. By comparison, the effect of pyruvate was not altered by BSO but was completely blocked by BCNU. Studies using inhibitors of signalling cascades indicated that upregulation of [GSH] by bpV(phen) in myocytes from post‐MI hearts was mediated by mitogen activated protein kinase/extracellular signal‐regulated kinase kinase 1/2 and p38 mitogen‐activated protein kinase but not by phosphatidylinositol 3‐kinase. The effect of pyruvate was not altered by any kinase inhibitor tested. In cells loaded with the probe TEMPO‐9‐AC to monitor superoxide anion, baseline fluorescence was 2.3‐fold greater in post‐MI myocytes than in sham control myocytes (P < 0.05) and was markedly decreased by diphenyleneiodonium (30 μmol l−1), an inhibitor of NADPH oxidase, exogenous GSH (10 mmol l−1) or bpV(phen). In parallel studies, [GSH] in post‐MI myocytes was also normalized by diphenyleneiodonium or exogenous GSH. These data show that GSH is differentially regulated by receptor tyrosine kinase‐dependent and ‐independent agonists that maintain functional GSH levels necessary to neutralize excess generation of reactive oxygen species in the failing heart.
Differential adaptations to eccentric versus conventional resistance training in older humans
Authors: Reeves Neil D. , Maganaris Constantinos N. , Longo Stefano , Narici Marco V.
Published: April 2009

We hypothesized that training with eccentric contractions only (therefore using higher loads) would yield greater muscle structural and strength gains compared with conventional resistance training. Nine older adults (mean ±s.d. age, 74 ± 3 years) were assigned to a conventional (CONV) resistance training group performing both concentric and eccentric contractions and 10 (age, 67 ± 2 years) to an eccentric‐only (ECC) resistance training group. Both groups trained three times per week for 14 weeks at 80% of the five‐repetition maximum, specific to each training mode. Maximal knee extensor torque was assessed during isometric, concentric and eccentric contractions across a range of angular velocities (0–3.49 rad s−1). Vastus lateralis muscle architecture (fascicle length, pennation angle and muscle thickness) was assessed in vivo at rest using ultrasonography. Training increased fascicle length in both groups, but the increase was significantly greater in the ECC (20% increase) than the CONV group (8% increase). Conversely, pennation angle significantly increased in the CONV (35% increase) but not in the ECC group (5% increase). Muscle thickness increased to a similar extent in both groups (∼12% increase). In the ECC group, eccentric knee extensor torque increased by 9–17% across velocities, but concentric torque was unchanged. Conversely, in the CONV group, concentric torque increased by 22–37% across velocities, but eccentric torque was unchanged. Instead, isometric torque increased to a similar extent in both groups (∼8% increase). Thus, the two training regimens resulted in differential adaptations in muscle architecture and strength. These results suggest that the stimulus for adding sarcomeres in‐series and in‐parallel may be different, which implies that different myogenic responses were induced by the two different training methods.
Developmental programming resulting from maternal obesity in mice: effects on myocardial ischaemia–reperfusion injury
Authors: Calvert John W. , Lefer David J. , Gundewar Susheel , Poston Lucilla , Coetzee William A.
Published: April 2009

A comprehensive number of epidemiological and animal studies suggest that prenatal and early life events are important determinants for disorders later in life. Among them, prenatal stress (i.e. stress experienced by the pregnant mother with impact on the fetal ontogeny) has clear programming effects on the cardiovascular system. A fetus developing in adverse conditions becomes an adult who is susceptible to disease, which may include hypertension, insulin resistance, altered blood lipid levels and cardiovascular disease. Recent evidence demonstrates that maternal programming can occur in the absence of other adverse environmental factors. Obesity, which is becoming a problem of large proportions in Western countries, is a possible cause of programming. With over 30% of the population of the USA currently obese, many mothers suffer from obesity during their child‐bearing years (in fact, these conditions are often aggravated during pregnancy). One of the targets of programming is the cardiovascular system, and reported consequences include hypertension, endothelial dysfunction and vascular abnormalities. The overall goal of our study was to investigate the susceptibility of the heart to ischaemia–reperfusion in an animal model of maternal obesity. Our data demonstrate that normal (non‐mutant) offspring from obese agouti mouse dams had an increased susceptibility to ischaemia–reperfusion injury. These data may provide insights into the long‐term cardiovascular consequences of programming.
Cardiac L‐type calcium current is increased in a model of hyperaldosteronism in the rat
Authors: Martin‐Fernandez Beatriz , Miana María , De las Heras Natalia , Ruiz‐Hurtado Gema , Fernandez‐Velasco María , Bas Manuel , Ballesteros Sandra , Lahera Vicente , Cachofeiro Victoria , Delgado Carmen
Published: April 2009

Accumulating evidence supports the importance of aldosterone as an independent risk factor in the pathophysiology of cardiovascular disease. It has been postulated that aldosterone could contribute to ventricular arrhythmogeneity by modulation of cardiac ionic channels. The aim of this study was to analyse ex vivo the electrophysiological characteristics of the L‐type cardiac calcium current (ICaL) in a model of hyperaldosteronism in the rat. Aldosterone was administered for 3 weeks, and cardiac collagen deposition and haemodynamic parameters were analysed. In addition, RT‐PCR and patch‐clamp techniques were applied to study cardiac L‐type Ca2+ channels in isolated cardiomyocytes. Administration of aldosterone induced maladaptive cardiac remodelling that was related to increased collagen deposition, diastolic dysfunction and cardiac hypertrophy. In addition, ventricular myocytes isolated from the aldosterone‐treated group showed increased ICaL density and conductance and prolongation of the action potential duration. No changes in kinetics or in voltage dependence of activation and inactivation of ICaL were observed, but relative expression of CaV1.2 mRNA levels was higher in cardiomyocytes isolated from the aldosterone‐treated group. The present study demonstrates that aldosterone treatment induces myocardial fibrosis, cardiac hypertrophy, increase of ICaL density, upregulation of L‐type Ca2+ channels and prolongation of action potential duration. It could be proposed that aldosterone, through these mechanisms, might exert pro‐arrhythmic effects in the pathological heart.
Co‐regulation of ocular dominance plasticity and NMDA receptor subunit expression in glutamic acid decarboxylase‐65 knock‐out mice
Authors: Kanold Patrick O. , Kim Yoon A. , GrandPre Tadzia , Shatz Carla J.
Published: May 2009

Experience can shape cortical circuits, especially during critical periods for plasticity. In visual cortex, imbalance of activity from the two eyes during the critical period shifts ocular dominance (OD) towards the more active eye. Inhibitory circuits are crucial in this process: OD plasticity is absent in GAD65KO mice that show diminished inhibition. This defect can be rescued by application of benzodiazepines, which increase GABAergic signalling. However, it is unknown how such changes in inhibition might disrupt and then restore OD plasticity. Since NMDA dependent synaptic plasticity mechanisms are also known to contribute to OD plasticity, we investigated whether NMDA receptor levels and function are also altered in GAD65KO. There are reduced NR2A levels and slower NMDA currents in visual cortex of GAD65KO mice. Application of benzodiazepines, which rescues OD plasticity, also increases NR2A levels. Thus it appears as if OD plasticity can be restored by adding a critical amount of excitatory transmission through NR2A‐containing NMDA receptors. Together, these observations can unify competing ideas of how OD plasticity is regulated: changes in either inhibition or excitation would engage homeostatic mechanisms that converge to regulate NMDA receptors, thereby enabling plasticity mechanisms and also ensuring circuit stability.
Regulators of PP2C Phosphatase Activity Function as Abscisic Acid Sensors
Authors: Ma Yue , Szostkiewicz Izabela , Korte Arthur , Moes Danièle , Yang Yi , Christmann Alexander , Grill Erwin
Published: May 2009

ABA Receptor Rumbled?

The plant hormone abscisic acid (ABA) is critical for normal development and for mediating plant responses to stressful environmental conditions. Now, two papers present analyses of candidate ABA receptors (see the news story by

Pennisi

).

Ma
et al.

(p. 1064; published online 30 April) and

Park
et al.

(p. 1068, published online 30 April) used independent strategies to search for proteins that physically interact with ABI family phosphatase components of the ABA response signaling pathway. Both groups identified different members of the same family of proteins, which appear to interact with ABI proteins to form a heterocomplex that can act as the ABA receptor. The variety of both families suggests that the ABA receptor may not be one entity, but rather a class of closely related complexes, which may explain previous difficulties in establishing its identity.
Robust Detection and Identification of Multiple Oomycetes and Fungi in Environmental Samples by Using a Novel Cleavable Padlock Probe-Based Ligation Detection Assay
Authors: van Doorn R. , Sławiak M. , Szemes M. , Dullemans A. M. , Bonants P. , Kowalchuk G. A. , Schoen C. D.
Published: April 2009

Simultaneous detection and identification of multiple pathogenic microorganisms in complex environmental samples are required in numerous diagnostic fields. Here, we describe the development of a novel, background-free ligation detection (LD) system using a single compound detector probe per target. The detector probes used, referred to as padlock probes (PLPs), are long oligonucleotides containing asymmetric target complementary regions at both their 5′ and 3′ ends which confer extremely specific target detection. Probes also incorporate a desthiobiotin moiety and an internal endonuclease IV cleavage site. DNA samples are PCR amplified, and the resulting products serve as potential targets for PLP ligation. Upon perfect target hybridization, the PLPs are circularized via enzymatic ligation, captured, and cleaved, allowing only the originally ligated PLPs to be visualized on a universal microarray. Unlike previous procedures, the probes themselves are not amplified, thereby allowing a simple PLP cleavage to yield a background-free assay. We designed and tested nine PLPs targeting several oomycetes and fungi. All of the probes specifically detected their corresponding targets and provided perfect discrimination against closely related nontarget organisms, yielding an assay sensitivity of 1 pg genomic DNA and a dynamic detection range of 10
4
. A practical demonstration with samples collected from horticultural water circulation systems was performed to test the robustness of the newly developed multiplex assay. This novel LD system enables highly specific detection and identification of multiple pathogens over a wide range of target concentrations and should be easily adaptable to a variety of applications in environmental microbiology.
Inactivation of Enteric Viruses in Minimally Processed Berries and Herbs
Authors: Butot S. , Putallaz T. , Amoroso R. , Sánchez G.
Published: April 2009

Several hepatitis A virus (HAV) and human norovirus (HuNoV) outbreaks due to consumption of contaminated berries and vegetables have recently been reported. Model experiments were performed to determine the effectiveness of freeze-drying, freeze-drying combined with heating, and steam blanching for inactivation of enteric viruses that might be present on the surface of berries and herbs. Inactivation of HAV and inactivation of feline calicivirus, a surrogate for HuNoV, were assessed by viral culturing and quantitative reverse transcription PCR (RT-PCR), whereas HuNoV survival was determined only by quantitative RT-PCR. While freeze-drying barely reduced (<1.3 log
10
units) the amount of HAV RNA detected in frozen produce, a greater decline in HAV infectivity was observed. The resistance of HuNoV genogroup I (GI) to freeze-drying was significantly higher than that of HuNoV GII on berries. Addition of a terminal dry heat treatment at 120°C after freeze-drying enhanced virus inactivation by at least 2 log
10
units, except for HuNoV GII. The results suggest that steam blanching at 95°C for 2.5 min effectively inactivated infectious enteric viruses if they were present in herbs. Our results provide data for adjusting food processing technologies if viral contamination of raw materials is suspected.
Optimization of a Phage Amplification Assay To Permit Accurate Enumeration of Viable
Mycobacterium avium
subsp.
paratuberculosis
Cells
Authors: Foddai Antonio , Elliott Christopher T. , Grant Irene R.
Published: April 2009

A commercially available phage amplification assay,
FASTPlaque
TB (Biotec Laboratories, Ipswich, United Kingdom), when used according to the manufacturer's instructions, does not permit accurate enumeration of
Mycobacterium avium
subsp.
paratuberculosis
. The aim of this study was to optimize the phage amplification assay conditions to permit accurate quantification of viable
M. avium
subsp.
paratuberculosis
cells. The burst time for
M. avium
subsp.
paratuberculosis
was initially determined to inform decisions about optimal incubation time before plating, and then other test parameters were altered to evaluate how the correlation between plaque and colony counts was affected. The D29 mycobacteriophage replicates more slowly in
M. avium
subsp.
paratuberculosis
than in
Mycobacterium smegmatis
(used to optimize the commercial test originally), and the mean burst time for four
M. avium
subsp.
paratuberulosis
strains was 210 ± 36.8 min at 37°C compared to 63 ± 17.5 min for
M. smegmatis
mc
2
155. To achieve 100% correlation between plaque and colony counts, the optimized phage assay includes the following: (i) resuspension of the samples to be tested in Middlebrook 7H9 broth containing 10% oleic acid-albumin-dextrose-catalase and 2 mM calcium chloride, followed by overnight incubation at 37°C before performance of the phage assay; (ii) a 2-h incubation of the sample with D29 mycobacteriophage before viricide treatment; and (iii) a further 90-min incubation after viricide treatment and neutralization up to the burst time (total incubation time, 210 min) before plating with
M. smegmatis
mc
2
155 in 7H9 agar. The optimized phage amplification assay was able to detect 1 to 10 CFU/ml of
M. avium
subsp.
paratuberculosis
in spiked milk or broth within 48 h, as demonstrated by the results of several blind trials.
Species-Specific Cell Wall Binding Affinity of the S-Layer Proteins of Mosquitocidal Bacterium
Bacillus sphaericus
C3-41
Authors: Li Jia , Hu Xiaomin , Yan Jianpin , Yuan Zhiming
Published: April 2009

The binding affinities and specificities of six truncated S-layer homology domain (SLH) polypeptides of mosquitocidal
Bacillus sphaericus
strain C3-41 with the purified cell wall sacculi have been assayed. The results indicated that the SLH polypeptide comprised of amino acids 31 to 210 was responsible for anchoring the S-layer subunits to the rigid cell wall layer via a distinct type of secondary cell wall polymer and that a motif of the recombinant SLH polypeptide comprising amino acids 152 to 210 (rSLH
152-210
) was essential for the stable binding of the S-layer with the bacterial cell walls. The quantitative assays revealed that the

K
D

(equilibrium dissociation constant) values of rSLH
152-210
and rSLH
31-210
with purified cell wall sacculi were 1.11 × 10
−6
M and 1.40 × 10
−6
M, respectively. The qualitative assays demonstrated that the SLH domain of strain C3-41 could bind only to the cell walls or the cells treated with 5 M guanidinium hydrochloride of both toxic and nontoxic
B. sphaericus
strains but not to those from other bacteria, indicating the species-specific binding of the SLH polypeptide of
B. sphaericus
with bacterial cell walls.
Characterization of the Tn
916
Conjugative Transposon in a Food-Borne Strain of
Lactobacillus paracasei
Authors: Devirgiliis Chiara , Coppola Doriana , Barile Simona , Colonna Bianca , Perozzi Giuditta
Published: April 2009

Food-borne antibiotic-resistant lactic acid bacteria have received growing attention in the past few years. We have recently identified tetracycline-resistant
Lactobacillus paracasei
in samples of milk and natural whey starter cultures employed in the manufacturing process of a typical Italian fermented dairy product, Mozzarella di Bufala Campana. In the present study, we have characterized at the molecular level the genetic context of tetracycline resistance determinants in these natural strains, which we have identified as
tet
(M). This gene was present in 21 independent isolates, whose fingerprinting profiles were distributed into eight different repetitive extragenic palindromic groups by cluster analysis. We provide evidence that the gene is associated with the broad-host, conjugative transposon Tn
916
, which had never before been described to occur in
L. paracasei
. PCR analysis of four independent isolates by use of specifically designed primer pairs detected the presence of a circular intermediate form of the transposon, carrying a coupling sequence (GGCAAA) located between the two termini of Tn
916
. This novel coupling sequence conferred low conjugation frequency in mating experiments with the recipient strain JH2-2 of
Enterococcus faecalis
.