bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of integrins in the periodontal ligament: organizers and facilitators
Authors: Barczyk Malgorzata , Bolstad Anne Isine , Gullberg Donald 
Published: August 2013

AbstractThe periodontal ligament is the tissue that connects teeth to bone. The periodontal ligament is a fascinating tissue from a cell biologist's point of view, and because of its special properties and stem‐cell content it has also come into the limelight in emerging fields of regenerative medicine. An increased range of genetically modified mouse models offer new tools for studying molecular mechanisms of tooth development. However, owing to species‐specific organization of the tooth apparatus, the use of genetic animal models to study the role of the periodontal ligament in normal human tooth physiology and tooth pathology is challenging.
Extracellular matrix mineralization in periodontal tissues: Noncollagenous matrix proteins, enzymes, and relationship to hypophosphatasia and X‐linked hypophosphatemia
Authors: McKee Marc D. , Hoac Betty , Addison William N. , Barros Nilana M. T. , Millán José L. , Chaussain Catherine 
Published: August 2013

AbstractAs broadly demonstrated for the formation of a functional skeleton, proper mineralization of periodontal alveolar bone and teeth – where calcium phosphate crystals are deposited and grow within an extracellular matrix – is essential for dental function. Mineralization defects in tooth dentin and cementum of the periodontium invariably lead to a weak (soft or brittle) dentition in which teeth become loose and prone to infection and are lost prematurely. Mineralization of the extremities of periodontal ligament fibers (Sharpey's fibers) where they insert into tooth cementum and alveolar bone is also essential for the function of the tooth‐suspensory apparatus in occlusion and mastication. Molecular determinants of mineralization in these tissues include mineral ion concentrations (phosphate and calcium), pyrophosphate, small integrin‐binding ligand N‐linked glycoproteins and matrix vesicles. Amongst the enzymes important in regulating these mineralization determinants, two are discussed at length here, with clinical examples given, namely tissue‐nonspecific alkaline phosphatase and phosphate‐regulating gene with homologies to endopeptidases on the X chromosome. Inactivating mutations in these enzymes in humans and in mouse models lead to the soft bones and teeth characteristic of hypophosphatasia and X‐linked hypophosphatemia, respectively, where the levels of local and systemic circulating mineralization determinants are perturbed. In X‐linked hypophosphatemia, in addition to renal phosphate wasting causing low circulating phosphate levels, phosphorylated mineralization‐regulating small integrin‐binding ligand N‐linked glycoproteins, such as matrix extracellular phosphoglycoprotein and osteopontin, and the phosphorylated peptides proteolytically released from them, such as the acidic serine‐ and aspartate‐rich‐motif peptide, may accumulate locally to impair mineralization in this disease.
Matrix mechanics and regulation of the fibroblast phenotype
Authors: Hinz Boris 
Published: August 2013

AbstractThe oral cavity hosts a variety of different fibroblast populations that are generally responsible for maintaining homeostasis of the soft connective tissue. In addition to regulating the turnover and structural arrangement of collagen and other proteins of the extracellular matrix, fibroblasts perform a number of specialized functions. Certain fibroblast subpopulations in the gingiva, oral mucosa and periodontal ligament serve as progenitor cells with multilineage differentiation and self‐renewal characteristics. In the periodontal ligament, fibroblasts further appear to function as mechanosensing entities that regulate collagen‐secretory and collagen‐remodeling activities according to the level of strain in the ligament. Mechanical challenge also plays an important role during the activation of periodontal fibroblasts in response to injury. Dysregulation of this activation process can lead either to poor healing and chronic wounds or to overly healed wounds with fibrosis. This review will elaborate on the roles of mechanical factors and mechanoperception in fibroblast activation, the molecular features of activated fibroblasts and the regulation mechanisms of fibroblast contraction. Pharmacological interference at each level is currently being pursued to improve the outcome of healing of injured periodontal tissue.
Expression of odontogenic ameloblast‐associated and amelotin proteins in the junctional epithelium
Authors: Nishio Clarice , Wazen Rima , Moffatt Pierre , Nanci Antonio 
Published: August 2013

AbstractTwo novel proteins – odontogenic ameloblast‐associated protein and amelotin – have recently been identified in maturation‐stage ameloblasts and in the junctional epithelium. This article reviews the structure and function of the junctional epithelium, the pattern of expression of odontogenic ameloblast‐associated and amelotin proteins and the potential involvement of these proteins in the formation and regeneration of the junctional epithelium.
Natural resolution of inflammation
Authors: Freire Marcelo O. , Van Dyke Thomas E. 
Published: August 2013

AbstractInflammation is a protective response essential for maintaining human health and for fighting disease. As an active innate immune reaction to challenge, inflammation gives rise to clinical cardinal signs: rubor, calor, dolor, tumor and functio laesa. Termination of acute inflammation was previously recognized as a passive process; a natural decay of pro‐inflammatory signals. We now understand that the natural resolution of inflammation involves well‐integrated, active, biochemical programs that return tissues to homeostasis. This review focuses on recent advances in the understanding of the role of endogenous lipid mediators that modulate cellular fate and inflammation. Biosynthesis of eicosanoids and other lipids in exudates coincides with changes in the types of inflammatory cells. Resolution of inflammation is initiated by an active class switch in lipid mediators, such as classic prostaglandins and leukotrienes, to the production of proresolution mediators. Endogenous pro‐resolving lipid mediators, including arachidonic acid‐derived lipoxins, aspirin‐triggered lipoxins, ω3‐eicosapentaenoic acid‐derived resolvins of the E‐series, docosahexaenoic acid‐derived resolvins of the D‐series, protectins and maresins, are biosynthesized during the resolution phase of acute inflammation. Depending on the type of injury and the type of tissue, the initial cells that respond are polymorphonuclear leukocytes, monocytes/macrophages, epithelial cells or endothelial cells. The selective interaction of specific lipid mediators with G protein‐coupled receptors expressed on innate immune cells (e.g. G protein‐coupled receptor 32, lipoxin A4 receptor/formyl peptide receptor2, chemokine‐like receptor 1, leukotriene B4 receptor type 1 and cabannoid receptor 2) induces cessation of leukocyte infiltration; vascular permeability/edema returns to normal with polymorphonuclear neutrophil death (mostly via apoptosis), the nonphlogistic infiltration of monocyte/macrophages and the removal (by macrophages) of apoptotic polymorphonuclear neutrophils, foreign agents (bacteria) and necrotic debris from the site. While an acute inflammatory response that is resolved in a timely manner prevents tissue injury, inadequate resolution and failure to return tissue to homeostasis results in neutrophil‐mediated destruction and chronic inflammation. A better understanding of the complex mechanisms of lipid agonist mediators, cell targets and actions allows us to exploit and develop novel therapeutic strategies to treat human inflammatory diseases, including periodontal diseases.
Information generation and processing systems that regulate periodontal structure and function
Authors: Bartold P. Mark , McCulloch Christopher A. 
Published: August 2013

AbstractThe periodontium is a very dynamic organ that responds rapidly to mechanical and chemical stimuli. It is very complex in that it is composed of two hard tissues (cementum and bone) and two soft connective tissues (periodontal ligament and gingiva). Together these tissues are defined by the molecules expressed by the resident periodontal cells in each compartment and this determines not only the structure and function of the periodontium but also how it responds to infection and inflammation. The biological activity of these molecules is tightly regulated in time and space to preserve tissue homeostasis, influence inflammatory responses and participate in tissue regeneration. In this issue of Periodontology 2000 we explore new experimental approaches and data sets which help to understand the molecules and cells that regulate tissue form and structure in health, disease and regeneration.
Association of hospitalizations for asthma with seasonal and pandemic influenza
Authors: Gerke Alicia K. , Yang Ming , Tang Fan , Foster Eric D. , Cavanaugh Joseph E. , Polgreen Philip M. 
Published: August 2013

AbstractBackground and objectiveAlthough influenza has been associated with asthma exacerbations, it is not clear the extent to which this association affects health care use in the United States. The first goal of this project was to determine whether, and to what extent, the incidence of asthma hospitalizations is associated with seasonal variation in influenza. Second, we used influenza trends (2000–2008) to help predict asthma admissions during the 2009 H1N1 influenza pandemic.MethodsWe identified all hospitalizations between 1998 and 2008 in the Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project during which a primary diagnosis of asthma was recorded. Separately, we identified all hospitalizations during which a diagnosis of influenza was recorded. We performed time series regression analyses to investigate the association of monthly asthma admissions with influenza incidence. Finally, we applied these time series regression models using 1998–2008 data, to forecast monthly asthma admissions during the 2009 influenza pandemic.ResultsBased on time series regression models, a strong, significant association exists between concurrent influenza activity and incidence of asthma hospitalizations (P‐value < 0.0001). Use of influenza data to predict asthma admissions during the 2009 H1N1 pandemic improved the mean squared prediction error by 60.2%.ConclusionsInfluenza activity in the population is significantly associated with asthma hospitalizations in the United States, and this association can be exploited to more accurately forecast asthma admissions. Our results suggest that improvements in influenza surveillance, prevention and treatment may decrease hospitalizations of asthma patients.
Optimal Designs for Dose Finding Studies with an Active Control
Authors: Dette Holger , Kiss, Christine , Benda Norbert , Bretz Frank 
Published: August 2013

SummaryDose finding studies often compare several doses of a new compound with a marketed standard treatment as an active control. In the past, however, research has focused mostly on experimental designs for placebo controlled dose finding studies. To the best of our knowledge, optimal designs for dose finding studies with an active control have not been considered so far. As the statistical analysis for an active controlled dose finding study can be formulated in terms of a mixture of two regression models, the related design problem is different from what has been investigated before in the literature. We present a rigorous approach to the problem of determining optimal designs for estimating the smallest dose achieving the same treatment effect as the active control. We determine explicitly the locally optimal designs for a broad class of models employed in such studies. We also discuss robust design strategies and determine related Bayesian and standardized minimax optimal designs. We illustrate the results by investigating alternative designs for a clinical trial which has recently appeared in a consulting project of one of the authors.
The Joint Graphical Lasso for Inverse Covariance Estimation Across Multiple Classes
Authors: Danaher Patrick , Wang Pei , Witten Daniela M. 
Published: August 2013

SummaryWe consider the problem of estimating multiple related Gaussian graphical models from a high dimensional data set with observations belonging to distinct classes. We propose the joint graphical lasso, which borrows strength across the classes to estimate multiple graphical models that share certain characteristics, such as the locations or weights of non-zero edges. Our approach is based on maximizing a penalized log-likelihood. We employ generalized fused lasso or group lasso penalties and implement a fast alternating directions method of multipliers algorithm to solve the corresponding convex optimization problems. The performance of the method proposed is illustrated through simulated and real data examples.
Sociodemographic and Clinical Differences Between Suicide Ideators and Attempters: A Study of Mood Disordered Patients 50 Years and Older
Authors: Pompili Maurizio , Innamorati Marco , Di Vittorio Cristina , Sher Leo , Girardi Paolo , Amore Mario 
Published: August 2013

Our study sought to characterize mood disordered suicide ideators and attempters 50 years and older admitted to a psychiatric ward either for a recent suicide attempt or for ongoing suicidal ideation. We enrolled 50 patients with suicide ideation consecutively admitted to an inpatient department and 50 patients admitted for a suicide attempt made in the last 48 hours. Suicide attempters more frequently had low social support and an age of onset of mood disorder of 46 years and older, and less frequently had a history of suicidal behaviors in the family members and pharmacological treatment, despite the fact that the groups did not differ with regard to antidepressants prescribed. The groups were not distinguishable based on several variables assumed to be risk factors for suicide behavior, such as proximal life events and stressors or alcohol use disorders. In both samples, comorbidity with organic diseases, the presence of stressful life events in the past 12 months, and a diagnosis of major depression were frequently reported. In conclusion, the presence of low social support and the absence of a pharmacotherapy may increase suicidal behaviors in patients at risk.
The Wild Side of Agro‐food Studies: On Co‐experimentation, Politics, Change, and Hope
Authors: Carolan Michael S. 
Published: August 2013

AbstractNoting that the field of agro‐food studies has undergone numerous ‘turns’ over the years, this article first seeks to make sense of this evolving literature by examining aspects of the metaphysical foreground upon which this ‘turning’ takes place. Doing this highlights a coalescing of sorts within the field; a movement the author describes as being less toward a specific theoretical framework as it is around a general way of doing agro‐food scholarship. This style of scholarship embraces relationality, process, and multiplicity while emphasising the generative capacities of what agro‐food scholars do for enacting novel political, ontological, and normative practices. The reminder of the article co‐experiments with what it means to be open to these productive capacities as researchers, in terms of making the un‐thought thinkable and un‐doable routine. In doing this the article offers an account of agro‐food imaginaries that is hopeful precisely because it is unsettling.
‘Our Entire People are Natural Born Friends of Peace’: The Norwegian Foreign Policy of Peace
Authors: Leira Halvard 
Published: August 2013

AbstractWhat makes a peace nation? In this article it is argued that the Norwegian foreign policy of peace is rooted in an historical self‐understanding of Norway and Norwegians as particularly peaceful, an identity which was first articulated around 1890. Norwegians hold a strong liberal/meliorist belief that the world can become a better place, and that Norway has an important role to play in this process. However, this general belief in peace and a Norwegian peaceful exceptionalism has been expressed in different ways over the last 120 years. Around 1900, the ideal was a passive state and an active people working for peace, while from around 1920 it was accepted that the state needed to take more active part. Where international peace activism was associated in particular withUNpeacekeeping during the Cold War, and peace mediation during the 1990's, increasingly a broader panoply of ‘good’ issues have been tied to an ever expanding notion of peace. The last two decades have also seen increased Norwegian participation in offensive military actions, couched at least partly in terms of peace. That the Norwegian attachment to peace remains strong while still allowing for support to military action suggests both that the Norwegian self‐understanding as a peace nation is deeply rooted and that it allows for a self‐righteous understanding of ‘peace through war’.
Low incidence of Pneumocystis jirovecii pneumonia in an unprophylaxed liver transplant cohort
Authors: Sarwar S. , Carey B. , Hegarty J.E. , McCormick P.A. 
Published: August 2013

AbstractBackgroundLiver transplant recipients are managed with a range of immunosuppressive regimens that place them at heightened risk of life‐threatening opportunistic infections such as Pneumocystis jirovecii pneumonia (PJP). No routine PJP prophylaxis is used at out institution. We reviewed the incidence of PJP in this cohort of unprophylaxed liver transplant recipients.MethodsWe examined all liver transplants performed between January 2000 and January 2012 in Ireland's National Liver Transplant Centre, St. Vincent's University Hospital, Dublin. Cases were identified through a computerized database and through the histopathology and microbiology registration system. The diagnosis of PJP was confirmed by identification of Pneumocystis cysts in bronchoalveolar lavage (BAL) fluid or on autopsy specimens using Grocott–Gomori methenamine‐silver nitrate or modified Wright–Giemsa staining methods.ResultsDuring the study period, 687 liver transplants were performed. We found 7 cases of PJP with an incidence rate of 0.84 per 1000 person transplant years. Five cases occurred within 12 months of transplant with 2 cases occurring at 56 and 60 months, respectively. Two cases were diagnosed at postmortem; 1 previously had negative cytology from BAL, while the other could not be bronchoscoped because of rapid deterioration in the clinical condition. Three of the 5 treated patients died.ConclusionsThe incidence of PJP in this cohort was very low, but the case fatality rate was high. Two cases occurred well after the usual recommended period of prophylaxis. In institutions with a very low risk of infection, targeted rather than universal prophylaxis may be reasonable.
A 22‐nt artificial microRNA mediates widespread RNA silencing in Arabidopsis
Authors: McHale Marcus , Eamens Andrew L. , Finnegan E. Jean , Waterhouse Peter M. 
Published: August 2013

SummaryIt is known that 22‐nucleotide (nt) microRNAs (miRNAs) derived from asymmetric duplexes trigger phased small‐interfering RNA (phasiRNA) production from complementary targets. Here we investigate the efficacy of 22‐nt artificial miRNA (amiRNA)‐mediated RNA silencing relative to conventional hairpin RNA (hpRNA) and 21‐nt amiRNA‐mediated RNA silencing. CHALCONE SYNTHASE (CHS) was selected as a target in Arabidopsis thaliana due to the obvious and non‐lethal loss of anthocyanin accumulation upon widespread RNA silencing. Over‐expression of CHS in the pap1‐D background facilitated visual detection of both local and systemic RNA silencing. RNA silencing was initiated in leaf tissues from hpRNA and amiRNA plant expression vectors under the control of an Arabidopsis RuBisCo small subunit 1A promoter (SSU). In this system, hpRNA expression triggered CHS silencing in most leaf tissues but not in roots or seed coats. Similarly, 21‐nt amiRNA expression from symmetric miRNA/miRNA* duplexes triggered CHS silencing in all leaf tissues but not in roots or seed coats. However, 22‐nt amiRNA expression from an asymmetric duplex triggered CHS silencing in all tissues, including roots and seed coats, in the majority of plant lines. This widespread CHS silencing required RNA‐DEPENDENT RNA POLYMERASE6‐mediated accumulation of phasiRNAs from the endogenous CHS transcript. These results demonstrate the efficacy of asymmetric 22‐nt amiRNA‐directed RNA silencing and associated phasiRNA production and activity, in mediating widespread RNA silencing of an endogenous target gene. Asymmetric 22‐nt amiRNA‐directed RNA silencing requires little modification of existing amiRNA technology and is expected to be effective in suppressing other genes and/or members of gene families.
Occult hepatitis B infections among blood donors in Lao PDR
Authors: Jutavijittum P. , Andernach I. E. , Yousukh A. , Samountry B. , Samountry K. , Thammavong T. , Keokhamphue J. , Toriyama K. , Muller C. P. 
Published: August 2013

Background and ObjectivesIn Lao People's Democratic Republic, hepatitis B virus is highly endemic. However, blood donations are only screened for HBsAg, leaving a risk of transmission by HBsAg‐negative occult infected donors. Here, we characterized first‐time blood donors to assess prevalence of hepatitis B virus infections and occult infected donors.Materials and MethodsSera were screened for HBsAg, HBeAg and anti‐HBs, anti‐HBc and anti‐HBe antibodies. Occult HBV infections (OBIs) were assessed in HBsAg‐negative sera by PCR, and sera of HBsAg positive and occult infected donors were phylogenetically characterized.Results9·6% of the donors were HBsAg positive, and 45.5% were positive for at least one of the hepatitis B virus serum markers. More than 40% HBsAg carriers were HBeAg positive, with HBeAg seroconversion occurring around 30 years of age. Furthermore, 10·9% of HBsAg‐negative, anti‐HBc and/or anti‐HBs‐positive donors were occult infected with hepatitis B virus. Thus, at least 3·9% of blood donations would potentially be unsafe, but hepatitis B virus DNA copy numbers greatly varied between donors.ConclusionIn Lao People's Democratic Republic, a sizable proportion of HBsAg‐negative and anti‐HBc antibody‐positive blood donations are potentially DNA positive and infective for hepatitis B.