bluuebunny/crossref_metadata_2025 huggingface dataset:
Strain amplification in bone mechanobiology: a computational investigation of the
in vivo
mechanics of osteocytes
Authors: Verbruggen Stefaan W. , Vaughan Ted J. , McNamara Laoise M.
Published: June 2012

The osteocyte is believed to act as the main sensor of mechanical stimulus in bone, controlling signalling for bone growth and resorption in response to changes in the mechanical demands placed on our bones throughout life. However, the precise mechanical stimuli that bone cells experience
in vivo
are not yet fully understood. The objective of this study is to use computational methods to predict the loading conditions experienced by osteocytes during normal physiological activities. Confocal imaging of the lacunar–canalicular network was used to develop three-dimensional finite element models of osteocytes, including their cell body, and the surrounding pericellular matrix (PCM) and extracellular matrix (ECM). We investigated the role of the PCM and ECM projections for amplifying mechanical stimulation to the cells. At loading levels, representing vigorous physiological activity (3000 µ
ɛ
), our results provide direct evidence that (i) confocal image-derived models predict 350–400% greater strain amplification experienced by osteocytes compared with an idealized cell, (ii) the PCM increases the cell volume stimulated more than 3500 µ
ɛ
by 4–10% and (iii) ECM projections amplify strain to the cell by approximately 50–420%. These are the first confocal image-derived computational models to predict osteocyte strain
in vivo
and provide an insight into the mechanobiology of the osteocyte.
Scaling of form and function in the xenarthran femur: a 100-fold increase in body mass is mitigated by repositioning of the third trochanter
Authors: Milne Nick , O'Higgins Paul
Published: June 2012

How animals cope with increases in body size is a key issue in biology. Here, we consider scaling of xenarthrans, particularly how femoral form and function varies to accommodate the size range between the 3 kg armadillo and its giant relative the 300 kg glyptodont. It has already been noted that femoral morphology differs between these animals and suggested that this reflects a novel adaptation to size increase in glyptodont. We test this idea by applying a finite element analysis of coronal plane forces to femoral models of these animals, simulating the stance phase in the hind limb; where the femur is subject to bending owing to longitudinal compressive as well as abduction loads on the greater trochanter. We use these models to examine the hypothesis that muscles attaching on the third trochanter (T3) can reduce this bending in the loaded femur and that the T3 forces are more effective at reducing bending in glyptodont where the T3 is situated at the level of the knee. The analysis uses traditional finite element methods to produce strain maps and examine strains at 200 points on the femur. The coordinates of these points before and after loading are also used to carry out geometric morphometric (GM) analyses of the gross deformation of the model in different loading scenarios. The results show that longitudinal compressive and abductor muscle loading increases bending in the coronal plane, and that loads applied to the T3 reduce that bending. In the glyptodont model, the T3 loads are more effective and can more readily compensate for the bending owing to longitudinal and abductor loads. This study also demonstrates the usefulness of GM methods in interpreting the results of finite element analyses.
PUNCTATE VASCULAR EXPRESSION1Is a Novel Maize Gene Required for Leaf Pattern Formation That Functions Downstream of the Trans-Acting Small Interfering RNA Pathway
Authors: Zhang Xiaolan , Douglas Ryan N. , Strable Josh , Lee Michelle , Buckner Brent , Janick-Buckner Diane , Schnable Patrick S. , Timmermans Marja C.P. , Scanlon Michael J.
Published: June 2012

The maize (Zea mays) gene RAGGED SEEDLING2-R (RGD2-R) encodes an ARGONAUTE7-like protein required for the biogenesis of trans-acting small interfering RNA, which regulates the accumulation of AUXIN RESPONSE FACTOR3A transcripts in shoots. Although dorsiventral polarity is established in the narrow and cylindrical leaves of rgd2-R mutant plants, swapping of adaxial/abaxial epidermal identity occurs and suggests a model wherein RGD2 is required to coordinate dorsiventral and mediolateral patterning in maize leaves. Laser microdissection-microarray analyses of the rgd2-R mutant shoot apical meristem identified a novel gene, PUNCTATE VASCULAR EXPRESSION1 (PVE1), that is down-regulated in rgd2-R mutant apices. Transcripts of PVE1 provide an early molecular marker for vascular morphogenesis. Reverse genetic analyses suggest that PVE1 functions during vascular development and in mediolateral and dorsiventral patterning of maize leaves. Molecular genetic analyses of PVE1 and of rgd2-R;pve1-M2 double mutants suggest a model wherein PVE1 functions downstream of RGD2 in a pathway that intersects and interacts with the trans-acting small interfering RNA pathway.
Gene flow and effective population size in two life‐history types of broad whitefish Coregonus nasus from the Canadian Arctic
Authors: Harris L. N. , Taylor E. B. , Tallman R. F. , Reist J. D.
Published: June 2012

In this study, the magnitude and direction of gene flow and estimates of effective population sizes (Ne) were quantified among two life‐history types (lacustrine and anadromous) of broad whitefish Coregonus nasus in the lower Mackenzie River system. The data suggest that dispersal and subsequent gene flow occurs between these groups, with the former appearing to be asymmetrical. Gene flow may potentially be directionally biased as well, a result attributed to source–sink population dynamics and the ongoing process of post‐glacial colonization and contemporary range expansion. Additionally, average Ne estimates were consistently lower for lacustrine populations of C. nasus although confidence intervals for both contemporary and historical estimates broadly overlapped. The lower average estimates of Ne for lacustrine populations was suggested to be the result of more recent founding events following post‐glacial dispersal. This study provides one of the first assessments of gene flow and Ne in an Arctic coregonine, results that may be relevant to other freshwater and anadromous Arctic species persisting in systems near the periphery of their range.
Characterization of MLSb resistance among Staphylococcus aureus and Staphylococcus epidermidis isolates carrying different SCCmec types
Authors: Teodoro Cristiane R. S. , Mattos Cláudio S. , Cavalcante Fernanda S. , Pereira Eliezer M. , Santos Kátia R. N. dos
Published: June 2012

This work characterizes MLSb resistance in 39 methicillin‐resistant Staphylococcus aureus (MRSA) and 32 Staphylococcus epidermidis (MRSE) isolates. Of 21 erm(A) gene encoding MRSA isolates, 71.4% carried SCCmecIII, whereas of 12 isolates carrying the erm(C) gene, 83.3% carried SCCmecIV. Among the 25 MRSE isolates positive for the erm(C) gene, 80% had SCCmecIV or nontypeable cassettes. Isolates carrying these genes had MIC90≥ 256 μg/mL to erythromycin and clindamycin. The msr(A) gene was associated with a low MIC90 to these drugs. The erm(A) gene was associated with SCCmecIII in MRSA isolates, whereas the erm(C) gene was associated with SCCmecIV in both MRSA and MRSE isolates.
(Un)‐blaming mothers whose partners sexually abuse children: in view of heteronormative myths, pressures and authorities
Authors: McLaren Helen Jaqueline
Published: June 2012

Mothers of children who have been sexually abused are often shamed, blamed and held guilty for their male partners' sexual perpetrations. These feelings are constrained by the dominant heteronormative discourses, institutions and systems that devalue women, that silence them and which subsequently blame women for the abuse as well as their silence. Paradoxically, the risks for mothers speaking out are reinforced by social criticism and professional response that draw on heteronormative discourses that accuse women for ‘failing to protect’ their children, for being ‘bad’ mothers or for making poor choices in their lovers. With these issues at the forefront, this paper illuminates how heteronormative discourses may operate to not only shame and blame women unable to leave their adult relationships and protect their children, but they also strengthen the perpetrator's power as strategic actors in concealing child sexual abuse. It is argued that the heteronormative discourses that reinforce women's sense of guilt obstruct professional intervention and make service engagement of these women difficult. In light of the power of discourse, the importance of combining an overlapping systems approach in which individualized client‐centred support is provided to each family member involved in child sexual abuse matters, including for the mothers in their own right, is discussed.
Activation of cytokines corroborate with development of inflammation and autoimmunity in thromboangiitis obliterans patients
Authors: Dellalibera-Joviliano R , Joviliano E E , Silva J S , Evora P R B
Published: June 2012

Thromboangiitis obliterans (TAO) is a segmental inflammatory occlusive disorder that affects the arm and leg arteries of young smokers. The immune system seems to play a critical role in the aetiology of TAO; however, knowledge of the aspects involved in the progression of vascular tissue inflammation and, consequently, the evolution of this disease is still limited. This study was carried out to investigate the cytokine levels of tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-4, IL-17 and IL-23 in the plasma of TAO patients presenting with acute clinical manifestations. The study included 20 TAO patients (n = 10 women; n = 10 men) aged 38–59 years under clinical follow-up, classified into two groups: (i) TAO former smokers (n = 11) and (ii) TAO active smokers (n = 9); the control groups included normal volunteer non-smokers (n = 10, active smokers (n = 10) and former smokers (n = 10). Patients' plasma samples were measured using the sandwich enzyme-linked immunosorbent assay. Statistical analyses were performed using the non-parametric Mann–Whitney U-test, with parameters significant at P < 0·05. The activities of all cytokines were different in groups of TAO patients when compared with normal controls, and decreased for control smokers. Increased levels of TNF-α, IL-1β, IL-4, IL-17 and IL-23 were significant in patients with TAO when compared to the controls (P < 0·005, all parameters). The results presented here indicate an increased production of cytokines in TAO, possibly contributing to the inflammatory response observed in the patients' vascular levels. In addition, the increased levels of IL-17 and IL-23 suggest that the disturbance of TAO is involved with mechanisms of autoimmunity. Thus, the discovery of IL-17 and its association with inflammation and autoimmune pathology has reshaped our viewpoint regarding the pathogenesis of TAO, which was based previously on the T helper type 1 (Th1)–Th2 paradigm.
Successful implementation of clinical practice guidelines for pressure risk management in a home nursing setting
Authors: Kapp Suzanne
Published: June 2012

Rationale  This paper reports an initiative which promoted evidence‐based practice in pressure risk assessment and management among home nursing clients in Melbourne, Australia.

Aim and objectives  The aim of this study was to evaluate the introduction and uptake of the Australian Wound Management Association Guidelines for the Prediction and Prevention of Pressure Ulcers.

Method  In 2007 a pilot study was conducted. Nurse perspectives (n=21) were obtained via survey and a client profile (n=218) was generated. Audit of the uptake and continued use of the pressure risk screening tool, during the pilot study and later once implemented as standard practice organizational wide, was conducted.

Results  Nurses at the pilot site successfully implemented the practice guidelines, pressure risk screening was adopted and supporting resources were well received. Most clients were at low risk of pressure ulcer development. The pilot site maintained and extended their pilot study success, ensuring more than 90% of clients were screened for pressure risk over the 18 months which followed. All other sites performed less well initially, however subsequently improved, meeting the pilot sites success after 18 months. Two years later, the organization continues to screen more than 90% of all clients for pressure risk.

Conclusion  Implementation of clinical practice guidelines was successful in the pilot project and pressure risk screening became a well‐adopted practice. Success continued following organizational wide implementation. Pilot study findings suggest it may be prudent to monitor the pressure ulcer risk status of low risk clients so as to prevent increasing risk and pressure ulcer development among this group.
Fish immune responses against endoparasitic nematodes – experimental models
Authors: Buchmann K
Published: June 2012

Vertebrates mount a series of immune reactions when invaded by helminths but antihelmintic immune strategies allow, in many cases, the first invaders of the non‐immune host to survive for prolonged periods, whereas subsequent larval invaders of the same parasite species face increased host resistance and thereby decreased colonization success. This concomitant immunity may represent a trade‐off between adverse side effects (associated with killing of large helminths in the host tissue) and the need for future protection against invasion. Encapsulation and isolation of large live endoparasitic larvae may be associated with less pathology compared to coping with excess dead parasite tissue in host organs. Likewise, live adult nematodes may be accepted in tissues at a certain activity level for the same reasons. Various host cell receptors bind helminth molecules after which signal‐transducing events lead to mobilization of specific reaction patterns depending on the combination of receptors and ligands involved. Both innate and adaptive responses (humoral and cellular) are prominent actors, but skewing of the Th1 lymphocyte response towards a Th2 type is a characteristic element of antihelminthic responses in mammalian hosts. Similar patterns may be expected also to occur in at least some fish species, such as salmonids, producing relevant cytokines, MHCII and CD4+ cells required for these lymphocyte subpopulations. Atlantic cod, Gadus morhua L., is without these immunological elements that indicate that alternative reaction pathways exist in at least some fish groups. Recent achievements within teleost immunology have made it possible to track these host responses in fish and the present work outlines the main immune reactions in fish against helminths and suggests three experimental fish models for exploration of these immune pathways in fish infected with nematodes.
Treatment of vibriosis in European sea bass larvae, Dicentrarchus labrax L., with oxolinic acid administered by bath or through medicated nauplii of Artemia franciscana (Kellogg): efficacy and residual kinetics
Authors: Touraki M , Niopas I , Karagiannis V.
Published: June 2012

European sea bass larvae were challenged by bath with Listonella anguillarum strain 332A, 2.5 × 107 CFU mL−1 for 1 h. Fish either received no treatment or oral treatment with Artemia franciscana (Kellog) nauplii enriched with oxolinic acid, or bath treatments with oxolinic acid. Medication commenced 1 day following challenge and was performed on days 1, 3 and 5 post‐challenge at a dosage of 20 mg L−1 for 2 h for bath treatments, while two doses each of 750 nauplii per fish were administered daily for five consecutive days in oral treatments. Cumulative mortality reached 96% for the unmedicated challenged group, 32% in the group receiving bath treatments and 17% in the group receiving medicated nauplii. Pharmacokinetic parameters of oxolinic acid were calculated in sea bass larvae, for both treatments. Steady‐state concentrations of oxolinic acid of 48.0 and 75.2 μg g−1 were achieved for bath treatment and oral treatment, respectively, while the elimination half‐life was calculated to be 25.1 h for bath treatment and 21.7 h for oral treatment.
Evaluation of digestive tolerance of a soluble corn fibre
Authors: Housez B. , Cazaubiel M. , Vergara C. , Bard J.‐M. , Adam A. , Einerhand A. , Samuel P.
Published: June 2012

Background:  To assess consumers’ acceptance of a new fibre, it is essential to evaluate its digestive tolerance after ingestion. We aimed to determine the tolerance of increasing dosages of Promitor™ Soluble Gluco Fibre (SGF; Tate&Lyle, Hoffman Estates, IL, USA) up to 70 g fibre per day using a validated gastrointestinal composite score.

Methods:  A composite score of gastrointestinal tolerance integrating gastrointestinal symptoms, stool frequency and consistency was applied. To statistically validate this composite score, the gastrointestinal tolerance of inulin (10 g versus 20 g containing, respectively, 9 g versus 18 g of fibre) was assessed in 18 healthy volunteers in a randomised double‐blind placebo‐controlled cross‐over study. Second, in a double‐blind placebo‐controlled cross‐over study with 20 healthy volunteers, the gastrointestinal tolerance of SGF in both acute and ‘spread over the day’ conditions of consumption was assessed.

Results:  By contrast to 10 g, 20 g of inulin demonstrated a significant difference in composite score compared to placebo [P < 0.001, difference = 7.6; 95% confidence interval (CI) = 3.8–11.3]. These values were considered as reference during the second study. In acute conditions, 40 g of SGF fibre was the highest (threshold) dose tested that indicates the digestive tolerance criteria (difference from placebo on the composite score <7.6 and upper limit of the 95% CI <11.3); this is twice the amount tolerated for inulin. In ‘spread over the day’ conditions, 65 g of SGF fibre was the threshold dose (P < 0.001, difference = 6.5; 95% CI = 3.4–9.5).

Conclusions:  The results of the present study demonstrate that 40 g of SGF fibre, when consumed as a single dose, and 65 g of SGF fibre, when consumed in multiple‐doses, across the day are well‐tolerated by healthy volunteers.
Intrinsic material length, Theory of Critical Distances and Gradient Mechanics: analogies and differences in processing linear‐elastic crack tip stress fields
Authors: ASKES H. , LIVIERI P. , SUSMEL L. , TAYLOR D. , TOVO R.
Published: June 2012

The Theory of Critical Distances (TCD) is a bi‐parametrical approach suitable for predicting, under both static and high‐cycle fatigue loading, the non‐propagation of cracks by directly post‐processing the linear‐elastic stress fields, calculated according to continuum mechanics, acting on the material in the vicinity of the geometrical features being assessed. In other words, the TCD estimates static and high‐cycle fatigue strength of cracked bodies by making use of a critical distance and a reference strength which are assumed to be material constants whose values change as the material microstructural features vary. Similarly, Gradient Mechanics postulates that the relevant stress fields in the vicinity of crack tips have to be determined by directly incorporating into the material constitutive law an intrinsic scale length. The main advantage of such a method is that stress fields become non‐singular also in the presence of cracks and sharp notches. The above idea can be formalized in different ways allowing, under both static and high‐cycle fatigue loading, the static and high‐cycle fatigue assessment of cracked/notched components to be performed without the need for defining the position of the failure locationsa priori.

The present paper investigates the existing analogies and differences between the TCD and Gradient Mechanics, the latter formalized according to the so‐called Implicit Gradient Method, when such theories are used to process linear‐elastic crack tip stress fields.
Long‐term outcome of the use of intravesical botulinum toxin for the treatment of overactive bladder (OAB)
Authors: Mohee Amar , Khan Ayisha , Harris Neil , Eardley Ian
Published: June 2012

What's known on the subject? and What does the study add?

It is known that intravesical botulinum toxin (BT) is an effective treatment for overactive bladder, especially in the patients with neurogenic detrusor overactivity. Several studies have shown that diagnostic and health‐related quality of life parameters improve after intravesical BT treatment.

The present study has the merit of reporting a ‘real‐life’ experience in a large teaching hospital in the UK National Health Service. As opposed to controlled trials, this retrospective study based largely on patient choice, shows that most patients fail to persist with intravesical BT treatment, mainly due to tolerability issues.

Objectives

To assess the long‐term compliance with repeated injections of intravesical botulinum toxin (BT) in a ‘real‐life’ mixed population of patients with idiopathic detrusor overactivity and neurogenic detrusor overactivity.

To identify the reasons why patients discontinued BT therapy and to explore the outcomes of those patients who did discontinue treatment.

Patients and Methods

Retrospective evaluation of the case notes of a series of patients who had received intravesical BT treatment at a large UK teaching hospital.

No antibiotic prophylaxis was given for the procedure.

Results

Over a period of 7 years, 268 patients were initiated on intravesical BT treatment for overactive bladder (OAB) at our institution, with 137 followed up for ≥36 months, with 80 patients having ≥60 months follow‐up after their first injection.

Almost two‐thirds of patients (61.3%) had discontinued intravesical BT therapy at 36 months, with a 63.8% discontinuation rate at 60 months.

The main reasons for discontinuation were tolerability issues, mainly urinary tract infections and the need for clean intermittent self‐catheterisation. Primary and secondary losses of efficacy were of secondary importance.

Most of the patients that discontinued have remained under urology care and now receive alternative methods of treatment.

Conclusions

Intravesical BT therapy is an effective short‐term treatment for OAB.

With time, two‐thirds of patients discontinued treatment usually because of the tolerability issues associated with treatment.
COMMON FACTORS OF THE EXCHANGE RISK PREMIUM IN EMERGING EUROPEAN MARKETS
Authors: Byrne Joseph P. , Nagayasu Jun
Published: June 2012

Existing empirical evidence suggests that the Uncovered Interest Rate Parity condition may not hold due to an exchange risk premium. For a panel dataset of eleven emerging European economies we decompose this exchange risk premium into an idiosyncratic (country‐specific) element and a common factor using a principal components approach. We present evidence of stationary idiosyncratic and common factors. This result leads to the conclusion of a stationary risk premium for these countries, which is consistent with previous studies often documenting a stationary premium in advanced countries. Furthermore, we report that the variation in the premium is largely attributable to a common factor influenced by economic developments in the United States.
Reaching the Limits of Secularization? Turkish‐ and Moroccan‐Dutch Muslims in the Netherlands 1998–2006
Authors: Maliepaard Mieke , Gijsberts Mérove , Lubbers Marcel
Published: June 2012

This research note focuses on Muslim minorities living in a secular context, the Netherlands. The question is whether mosque attendance among Turkish‐ and Moroccan‐Dutch changed between 1998 and 2006, testing mechanisms of religious decline and religious vitality. Elaborating on previous research of the same Muslim groups, this study examines a longer time span and adds contextual‐level explanations. Whereas previous research reported a linear trend towards secularization over time and over generations, in recent years the trend has become more complex. The revival of religious attendance among the second generation is most striking. Forces of secularization such as educational attainment and generational replacement gradually lose their predictive power. Over time, processes of secularization are therefore not inevitable.
Warrior Chicks: Youthful Aging in a Postfeminist Prosperity Discourse
Authors: Jenkins Kathleen E. , Marti Gerardo
Published: June 2012

In a youth‐oriented evangelical congregation where being perceived as “old” might marginalize member involvement and participation, a Hollywood, California congregation's women's ministry, God Chicks, presents aging women as possessing “godly wisdom,” endowing older women with spiritually charged energy, authority, and responsibility for training younger women to live “godly” lives. Ethnographic research and in depth media analysis of the God Chicks ministry reveals a particularly energizing evangelical postfeminist orientation that applies prosperity theology to contemporary challenges of changing women's roles. Specifically, the God Chicks ministry provides “women over forty” with consumer and caretaking strategies for maintaining youthful selves and motivating younger women. A “God Chick” emerges as a compelling, youthful gendered religious identity that expects congregationally committed women to be strong, healthy, and active warriors who fight multiple relational and global humanitarian battles. Overall, this study demonstrates the construction of an innovative postfeminist evangelical identity through the tactical, opportunistic use of theological doctrine by ministry leaders within a particularistic geographic location.
Patterns of habitat use by female brown long‐eared bats presage negative impacts of woodland conservation management
Authors: Murphy S. E. , Greenaway F. , Hill D. A.
Published: June 2012

Reinstating forestry practices, such as coppicing, thinning the understorey and grazing, has become a key element of proposals for improving the conservation value of broadleaved woodlands in Europe. However, the consequences of such woodland management for bats are poorly understood because of a lack of knowledge concerning their habitat requirements. We studied the brown long‐eared bat Plecotus auritus in South East England to determine how their patterns of habitat use could inform conservation management. Radio‐tracking of 38 adult females showed that they foraged primarily in woodland and that each had a foraging area (mean = 4.4 ha) that they returned to on successive nights. Core foraging areas (mean = 2.1 ha) were characterized by more cover and greater species diversity in the understorey layer than more peripheral areas. Hedgerows were also used for foraging in the late summer and autumn. Most conservation activities for this species have focused on protecting roosts in houses and other buildings. While such protection is important for bat conservation, efforts should also be made to protect foraging habitats in woodlands by maintaining cover of native species in the understorey layer and hedgerows that provide connectivity between woodland patches. Common conservation management practices, such as reinstating coppicing or grazing in semi‐natural broadleaved woodlands, could be detrimental for P. auritus and other woodland bats. Their impact on bats should be tested experimentally before they are widely promoted as a woodland conservation strategy.
Phase Transition Behavior of the (1−x)PbZrO3−xBa(Al1/2Nb1/2)O3 Solid Solution
Authors: Sukkha Usa , Vittayakorn Wanwilai , Muanghlua Rangson , Niemcharoen Surasak , Boonchom Banjong , Vittayakorn Naratip
Published: June 2012

Solid solution of the (1−x)PbZrO3−xBa(Al1/2Nb1/2)O3 system, with x = 0.02–0.30, was prepared using solid state reaction. The effect of Ba(Al1/2Nb1/2)O3 on phase transitions and thermal and electrical properties was investigated. The stability of ferroelectric phase in pure PZ was found to improve with increasing BAN content, which corresponded to the increased tolerance factor (t) of solid solution. In comparison to other systems, results in this study indicated that the tolerance factor can predict the ferroelectric (FE)/antiferroelectric (AFE) stability of PZ‐based solid solution. If the t value of solid solution is higher than pure PZ, the FE phase can be induced. On the other hand, the AFE phase is stabilized when the t value of solid solution is lower than pure PZ.
Forecasting pseudo‐periodic seasonal patterns in agricultural prices
Authors: Martín‐Rodríguez Gloria , Cáceres‐Hernández José Juan
Published: June 2012

A seasonal model is proposed to forecast agricultural prices with pseudo‐periodic seasonal patterns, in which the length of the seasonal period does not remain the same over time. The seasonal effect at a season is defined as a function of the proportion of the seasonal period length elapsed up to that season, and the seasonal pattern is modeled by means of evolving splines to capture any dynamic process of change. Such a model is a useful tool to forecast seasonal behaviors. To illustrate the relevance of this modeling framework, the methodology is applied to weekly prices of tomatoes exported to German markets.
A Cross‐Talk of Decidual Stromal Cells, Trophoblast, and Immune Cells: A Prerequisite for the Success of Pregnancy
Authors: Oreshkova Tsvetelina , Dimitrov Roumen , Mourdjeva Milena
Published: June 2012

Embryo implantation and formation of a functional placenta are complex processes that require a plethora of regulatory mechanisms involving both mother and embryo cells. Recently, an important role in this complicated cells and factors network was assigned to the decidual stromal cells (DSC) and trophoblast cells. Decidualization includes biochemical changes that trigger DSC to produce a number of factors required for the implantation and induction of immunotolerance in maternal immune system. Immunotolerance is achieved by a cascade of strictly controlled events starting with selective homing of immune cells to the feto‐maternal site, regulated proliferation, and predominant differentiation into a regulatory type of immune cells. Furthermore, cytotoxic effector functions are reduced owing to the influence of steroid hormones, factors, cytokines, and inhibitory receptors. Altogether the entire immune system of the mother is switched to tolerogenic functional state which is a prerequisite for the successful maintenance of pregnancy.
Relationships between muscle growth potential, intramuscular fat content and different indicators of muscle fibre types in young Charolais bulls
Authors: HOCQUETTE Jean‐François , CASSAR‐MALEK Isabelle , JURIE Catherine , BAUCHART Dominique , PICARD Brigitte , RENAND Gilles
Published: June 2012

Genetic selection in favor of muscle growth at the expense of fat should affect characteristics of muscles, and therefore beef quality. This study was conducted with two extreme groups of six animals selected among 64 Charolais young bulls ranked according to their genetic potential for muscle growth. Muscle characteristics were assessed inRectus abdominis(RA, slow oxidative) andSemitendinosus(ST, fast glycolytic) muscles. Intramuscular fat content and proportions of myosin heavy chains I (slow) and IIA (fast oxido‐glycolytic) and certain indicators of oxidative metabolism (activities of citrate synthase (CS), isocitrate dehydrogenase and cytochrome‐coxidase (COX); expression of H‐fatty acid binding protein (FABP)) were higher in RA than in ST muscle. Genetic selection for muscle growth reduced intramuscular fat content and the activities of some oxidative metabolism indicators (namely CS, COX only). The positive correlation between muscle triacylglycerol content and A‐FABP messenger RNA level (a marker of adipocyte differentiation) (r = 0.53,P < 0.05) suggests that A‐FABP may be a good marker of the ability of bovines to deposit intramuscular fat. In conclusion, the metabolic muscle characteristics which respond to the selection process in favor of muscle growth clearly differ from the muscle characteristics which allow muscle types to be differentiated.
Understanding the rise of the regulatory state of the South*
Authors: Dubash Navroz K. , Morgan Bronwen
Published: June 2012

This paper, and the special issue it introduces, explores whether, and how, the rise of the regulatory state of the South, and its implications for processes of governance, are distinct from cases in the North. With the exception of a small but growing body of work on Latin America, most work on the regulatory state deals with the US or Europe, or takes a relatively undifferentiated “legal transplant” approach to the developing world. We use the term “the South” to invoke shared histories of many countries, rather than as a geographic delimiter, even while acknowledging continued and growing diversity among these countries, particularly in their engagement with globalization.

We suggest that three aspects of this common context are important in characterizing the rise of the regulatory state of the South. The first contextual element is the presence of powerful external pressures, especially from international financial institutions, to adopt the institutional innovation of regulatory agencies in infrastructure sectors. The result is often an incomplete engagement with and insufficient embedding of regulatory agencies within local political and institutional context. A second is the greater intensity of redistributive politics in settings where infrastructure services are of extremely poor quality and often non‐existent. The resultant politics of distribution draws in other actors, such as the courts and civil society; regulation is too important to be left to the regulators. The third theme is that of limited state capacity, which we suggest has both “thin” and “thick” dimensions. Thin state capacity issues include prosaic concerns of budget, personnel and training; thick issues address the growing pressures on the state to manage multiple forms of engagement with diverse stakeholders in order to balance competing concerns of growth, efficiency and redistribution.

These three themes provide a framework for this special issue, and for the case studies that follow. We focus on regulatory agencies in infrastructure sectors (water, electricity and telecoms) as a particular expression of the regulatory state, though we acknowledge that the two are by no means synonymous. The case studies are drawn from India, Colombia, Brazil, and the Philippines, and engage with one or more of these contextual elements. The intent is to draw out common themes that characterize a “regulatory state of the South,” while remaining sensitive to the variations in level of economic development and political institutional contexts within “the South.”
Perspectives on tight junction research
Authors: Schulzke Jörg‐Dieter , Günzel Dorothee , John Lena J. , Fromm Michael
Published: June 2012

The tight junction connects neighboring epithelial or endothelial cells. As a general function, it seals the paracellular pathway and thus prevents back‐leakage of just transported solutes and water. However, not all tight junctions are merely tight: some tight junction proteins build their own transport pathways by forming channels selective for small cations, anions, or water. Two families of tight junction proteins have been identified, claudins (27 members in mammals) and tight junction‐associated MARVEL proteins ((TAMPs) occludin, tricellulin, and MarvelD3); an additional, structurally different, junction protein is junction adhesion molecule (JAM). Besides classification by genetic or molecular kinship, classification of tight junction proteins has been suggested according to permeability attributes. Recent studies describe specific cis and trans interactions and manifold physiologic regulations of claudins and TAMPs. In many inflammatory and infectious diseases they are found to be altered, for example, causing adversely increased permeability. Currently, attempts are being made to alter the paracellular barrier for therapeutic interventions or for transiently facilitating drug uptake. This overview concludes with a list of open questions and future topics in tight junction research.
Claudins and alveolar epithelial barrier function in the lung
Authors: Frank James A.
Published: June 2012

The alveolar epithelium of the lung constitutes a unique interface with the outside environment. This thin barrier must maintain a surface for gas transfer while being continuously exposed to potentially hazardous environmental stimuli. Small differences in alveolar epithelial barrier properties could therefore have a large impact on disease susceptibility or outcome. Moreover, recent work has focused attention on the alveolar epithelium as central to several lung diseases, including acute lung injury and idiopathic pulmonary fibrosis. Although relatively little is known about the function and regulation of claudin tight junction proteins in the lung, new evidence suggests that environmental stimuli can influence claudin expression and alveolar barrier function in human disease. This review considers recent advances in the understanding of the role of claudins in the breakdown of the alveolar epithelial barrier in disease and in epithelial repair.
Charge‐selective claudin channels
Authors: Krug Susanne M. , Günzel Dorothee , Conrad Marcel P. , Lee In‐Fah M. , Amasheh Salah , Fromm Michael , Yu Alan S. L.
Published: June 2012

Claudins are the main determinants of barrier properties of the tight junction. Many claudins have been shown to act by tightening the paracellular pathway, but several function as paracellular channels. While some depend on the endogenous claudin background of the analyzed cell line, for other claudins, a distinct charge‐selectivity has been shown. This paper portrays cation‐selective (claudin‐2, claudin‐10b, claudin‐15) and anion‐selective (claudin‐10a, claudin‐17) claudins and claudins with debatable channel properties (claudin‐4, claudin‐7, claudin‐16). It also describes molecular properties determining the observed charge‐selectivity and pore properties in general. In leaky tissues, they widely determine overall transport characteristics by providing paracellular ion‐selective pathways. In small intestine, claudin‐2 and claudin‐15 replace each other in the developing gut. In kidney proximal tubules, claudin‐2, claudin‐10, and claudin‐17 allow for paracellular reabsorption of sodium, chloride, and water.
Claudin‐derived peptides are internalized via specific endocytosis pathways
Authors: Zwanziger Denise , Staat Christian , Andjelkovic Anuska V. , Blasig Ingolf E.
Published: June 2012

Claudin proteins are involved in the paracellular tightening of epithelia and endothelia. Their internalization, which can be modulated by extracellular stimuli, for example, proinflammatory cytokines, is a prerequisite for the regulation of the paracellular barrier to allow, for instance, cell migration or drug delivery. The internalization of peptide sequences of claudins is completely unknown. Here, we studied the internalization of two peptides, TAMRA‐claudin‐1 and TAMRA‐claudin‐5, derivatives of the extracellular loop of claudin‐1 and ‐5, respectively, in either epithelial or endothelial cells. The cellular uptake of the claudin‐1 peptide follows the clathrin‐mediated endocytosis as indicated by inhibitors and respective tracers for colocalization. In addition, macropinocytosis and caveolae‐mediated endocytosis of the peptide was observed. In contrast, the claudin‐5 peptide is mainly internalized via the caveolae‐mediated endocytosis evidenced by the colocalization with respective tracers and vesicle markers, whereas the nonselective macropinocytosis seems to be involved in a less effective manner. In conclusion, the assumption is supported that claudin peptides can be internalized by specific and nonspecific pathways.
The role for protein tyrosine phosphatase nonreceptor type 2 in regulating autophagosome formation
Authors: Scharl Michael , Rogler Gerhard
Published: June 2012

Genome‐wide association studies have identified single nucleotide polymorphisms within the gene locus encoding protein tyrosine phosphatase nonreceptor type 2 (PTPN2) as a risk factor for the development of chronic inflammatory diseases, such as inflammatory bowel disease (IBD), type 1 diabetes, and rheumatoid arthritis. IBD is characterized by a breakdown of the intestinal epithelial barrier function leading to an overwhelming and uncontrolled immune response to bacterial antigens. Recent studies demonstrated that PTPN2 regulates cytokine‐induced signaling pathways, epithelial barrier function, and cytokine secretion in human intestinal cells. Dysfunction of PTPN2 is also associated with impaired autophagosome formation and defective bacterial handling in intestinal cells. All of these cellular functions have been demonstrated to play a crucial role in the pathogenesis of IBD. The genetic variations within the PTPN2 gene may result in altered protein function, thereby essentially contributing to the onset and perpetuation of chronic inflammatory conditions in the intestine.
Within‐patient variation of hemoglobin and reticulocytes: implications for evaluating ESA responsiveness in dialysis patients
Authors: Van Wyck D. B. , Giles I. , Sharpe K.
Published: June 2012

Introduction:  Techniques that assess percent reticulocytes (%retics) or hemoglobin (Hb) to detect erythropoiesis‐stimulating agents (ESA) use in athletes may be useful in evaluating ESA responsiveness in dialysis patients. However, within‐patient variation, appropriate transformation, or the relationship between the blood draw interval length and analyte variation are untested.

Methods:  In a prospective, single‐arm trial, we determined Hb and %retics in 30 hemodialysis patients receiving stable ESA doses. Within‐patient results were evaluated for variance homogeneity and normality with and without transformation.

Results:  Square‐root transformation (sqrt) of %retics produced the most constant variance (lowest r‐value for correlation between sqrt|normalized residuals| and fitted values: 0.018 highest P‐value 0.739) compared with log transformation (r = −0.198, P < 0.001) or no transformation (r = 0.215, P < 0.001) and showed the least departure from normality (highest P‐value: 0.002 vs. < 0.001 vs. < 0.001, respectively). Hb results did not improve with transformation. Within‐patient variance in both %retics and Hb increased with interval length between lab draws (P < 0.001).

Conclusions:  Initial assessment of anti‐doping tool use in dialysis patient anemia management indicates square‐root transformation of %retics and adjustment for time between lab draw intervals for both %retics and Hb will be required.
RAD sequencing yields a high success rate for westslope cutthroat and rainbow trout species‐diagnostic SNP assays
Authors: AMISH STEPHEN J. , HOHENLOHE PAUL A. , PAINTER SALLY , LEARY ROBB F. , MUHLFELD CLINT , ALLENDORF FRED W. , LUIKART GORDON
Published: June 2012

Hybridization with introduced rainbow trout threatens most native westslope cutthroat trout populations. Understanding the genetic effects of hybridization and introgression requires a large set of high‐throughput, diagnostic genetic markers to inform conservation and management. Recently, we identified several thousand candidate single‐nucleotide polymorphism (SNP) markers based on RAD sequencing of 11 westslope cutthroat trout and 13 rainbow trout individuals. Here, we used flanking sequence for 56 of these candidate SNP markers to design high‐throughput genotyping assays. We validated the assays on a total of 92 individuals from 22 populations and seven hatchery strains. Forty‐six assays (82%) amplified consistently and allowed easy identification of westslope cutthroat and rainbow trout alleles as well as heterozygote controls. The 46 SNPs will provide high power for early detection of population admixture and improved identification of hybrid and nonhybridized individuals. This technique shows promise as a very low‐cost, reliable and relatively rapid method for developing and testing SNP markers for nonmodel organisms with limited genomic resources.
The novel ‘CandidatusAmphibiichlamydia ranarum’ is highly prevalent in invasive exotic bullfrogs (Lithobates catesbeianus)
Authors: Martel An , Adriaensen Connie , Sharifian‐Fard Mojdeh , Vandewoestyne Mado , Deforce Dieter , Favoreel Herman , Bergen Karolien , Spitzen‐van der Sluijs Annemarieke , Devisscher Sander , Adriaens Tim , Louette Gerald , Baert Kristof , Hyatt Alex , Crameri Sandra , Haesebrouck Freddy , Pasmans Frank
Published: June 2012

Knowledge concerning microbial infectious diseases in the current amphibian crisis is rudimentary and largely limited to ranavirosis and chytridiomycosis. The familyChlamydiaceaeis gaining attention as a common cause of disease in amphibians and may harbour new and emerging amphibian pathogens. We identified a novel species of Chlamydiales (CandidatusAmphibiichlamydia ranarum) with a prevalence of 71% in exotic invasive bullfrog tadpoles (Lithobates catesbeianus) from an introduced population in the Netherlands. The sequence of a 1474 bp 16S rRNA gene fragment showed that the novel taxon forms a well‐defined clade with ‘CandidatusAmphibiichlamydia salamandrae’ within theChlamydiaceaefamily. Although none of the tadpoles examined showed signs of clinical disease, urgent evaluation of its pathogenic potential for native amphibian species is required.
Frequencies of Circular Plates Weakened Along an Internal Concentric Circle and Elastically Restrained Edge Against Translation
Authors: Rao Lokavarapu Bhaskara , Rao Chellapilla Kameswara
Published: June 2012

The present study deals with the derivation of an exact solution for the problem of obtaining the natural frequencies of the vibration of circular plates weakened along an internal concentric circle due to the presence of a radial crack and elastically restrained along the outer edge of the plate against translation. The frequencies of the circular plates are computed for varying values of the elastic translational restraint, the radius of the radial crack, and the extent of the weakening duly simulated by considering the radial crack as a radial elastic rotational restraint on the plate. The results for the first six modes of the plate vibrations are computed. The effects of the elastic edge restraint, the radius of the weakened circle, and the extent of the weakening represented by an elastic rotational restraint on the vibration behavior of thin circular plates are studied in detail. The internal weakening due to a crack resulted in decreasing the fundamental frequency of the plate. The exact method of solution and the results presented in this paper are expected to be of specific use in analyzing the effect of a radial crack on the fundamental natural frequency of the circular plate in the presence of a translational restraint existing along the outer edge of the plate. These exact solutions can be used to check the numerical or approximate results.
Analysis of Thin-Walled Structures With Longitudinal and Transversal Stiffeners
Authors: Carrera E. , Zappino E. , Petrolo M.
Published: June 2012

This paper proposes the use of a one-dimensional (1D) structural theory to analyze thin walled structures with longitudinal and transverse stiffeners. The 1D theory has hierarchical features and it is based on the unified formulation (UF) which has recently been introduced by Carrera. UF permits us to introduce any order of expansion (N) for the unknown displacements over the cross section by preserving the compact form of the related governing equations. In this paper the latter are written in terms of finite element matrices. The same 1D structural theory is used to model a given thin-walled structure composed of stiffened (longitudinal and transverse) and unstiffened parts. It is shown that an appropriate choice of N permits us to accurately describe strain/stress fields of both transverse and longitudinal stiffeners. Comparisons with available results from open literature highlight the efficiency of the proposed model. Moreover, a set of sample problems are proposed and compared with plate/shell formulations from a commercial finite element (FE) software.