Sex hormones and adult hippocampal neurogenesis: Regulation, implications, and potential mechanisms.
Mahmoud, Rand; Wainwright, Steven R; Galea, Liisa A M
2016-04-01
Neurogenesis within the adult hippocampus is modulated by endogenous and exogenous factors. Here, we review the role of sex hormones in the regulation of adult hippocampal neurogenesis in males and females. The review is framed around the potential functional implications of sex hormone regulation of adult hippocampal neurogenesis, with a focus on cognitive function and mood regulation, which may be related to sex differences in incidence and severity of dementia and depression. We present findings from preclinical studies of endogenous fluctuations in sex hormones relating to reproductive function and ageing, and from studies of exogenous hormone manipulations. In addition, we discuss the modulating roles of sex, age, and reproductive history on the relationship between sex hormones and neurogenesis. Because sex hormones have diverse targets in the central nervous system, we overview potential mechanisms through which sex hormones may influence hippocampal neurogenesis. Lastly, we advocate for a more systematic consideration of sex and sex hormones in studying the functional implications of adult hippocampal neurogenesis. Copyright © 2016 Elsevier Inc. All rights reserved.
The local work function: Concept and implications
NASA Astrophysics Data System (ADS)
Wandelt, K.
1997-02-01
The term 'local work function' is now widely applied. The present work discusses the common physical basis of 'photoemission of adsorbed xenon (PAX)' and 'two-photon photonemissionspectroscopy of image potential states' as local work function probes. New examples with bimetallic and defective surfaces are presented which demonstrate the capability of PAX measurements for the characterization of heterogeneous surfaces on an atomic scale. Finally, implications of the existence of short-range variations of the surface potential at surface steps are addressed. In particular, dynamical work function change measurements are a sensitive probe for the step-density at surfaces and, as such, a powerful in-situ method to monitor film growth.
Rouleau, Nicolas; Dotta, Blake T
2014-01-01
Within a cell system structure dictates function. Any interaction between cells, or a cell and its environment, has the potential to have long term implications on the function of a given cell and emerging cell aggregates. The structure and function of cells are continuously subjected to modification by electrical and chemical stimuli. However, biological systems are also subjected to an ever-present influence: the electromagnetic (EM) environment. Biological systems have the potential to be influenced by subtle energies which are exchanged at atomic and subatomic scales as EM phenomena. These energy exchanges have the potential to manifest at higher orders of discourse and affect the output (behavior) of a biological system. Here we describe theoretical and experimental evidence of EM influence on cells and the integration of whole systems. Even weak interactions between EM energies and biological systems display the potential to affect a developing system. We suggest the growing literature of EM effects on biological systems has significant implications to the cell and its functional aggregates.
Mapping Language Function in the Brain: A Review of the Recent Literature.
ERIC Educational Resources Information Center
Crafton, Robert E.; Kido, Elissa
2000-01-01
Considers the potential importance of brain study for composition instruction, briefly describes functional imaging techniques, and reviews the findings of recent brain-mapping studies investigating the neurocognitive systems involved in language function. Presents a review of the recent literature and considers the possible implications of this…
ERIC Educational Resources Information Center
Larbi-Apau, Josephine A.; Moseley, James L.
2012-01-01
This study examined the validity of Selwyn's computer attitude scale (CAS) and its implication for technology-based performance of randomly sampled (n = 167) multidiscipline teaching faculty in higher education in Ghana. Considered, computer attitude is a critical function of computer attitude and potential performance. Composed of four…
Dynamics of endoglucanase catalytic domains: implications towards thermostability
USDA-ARS?s Scientific Manuscript database
The function of proteins is controlled by their dynamics inherently determined by their structure. Exploring the protein structure-dynamics relationship is important to develop an understanding of protein function that allows tapping the potential of economically important proteins, such as endogluc...
Potential effects of restoration on biogeochemical functions of bottom land hardwood ecosystems
Graeme Lockaby; John A. Stanturf
2000-01-01
The concept of wetland restoration carries multiple meanings and implications. The scientific usage of the term connotes re-establishment of wetland functions, and often it is the functions, which society deems most valuable, that receive highest focus. Arguably, among key wetland functions, the highest societal value may be linked with the biogeochemical...
Mitochondrial dysfunction has been implicated in the pathogenesis of a variety of disorders including cancer, diabetes, and neurodegenerative and cardiovascular diseases. Understanding how different environmental chemicals and drug-like molecules impact mitochondrial function rep...
The thermolysin family (M4) of enzymes: therapeutic and biotechnological potential.
Adekoya, Olayiwola A; Sylte, Ingebrigt
2009-01-01
Zinc containing peptidases are widely distributed in nature and have important roles in many physiological processes. M4 family comprises numerous zinc-dependent metallopeptidases that hydrolyze peptide bonds. A large number of these enzymes are implicated as virulence factors of the microorganisms that produce them and are therefore potential drug targets. Some enzymes of the family are able to function at the extremes of temperatures, and some function in organic solvents. Thereby enzymes of the thermolysin family have an innovative potential for biotechnological applications.
Mortazavi, Martin M; Griessenauer, Christoph J; Adeeb, Nimer; Deep, Aman; Bavarsad Shahripour, Reza; Shahripour, Reza Bavarsad; Loukas, Marios; Tubbs, Richard Isaiah; Tubbs, R Shane
2014-02-01
The role of the choroid plexus in cerebrospinal fluid production has been identified for more than a century. Over the years, more intensive studies of this structure has lead to a better understanding of the functions, including brain immunity, protection, absorption, and many others. Here, we review the macro- and microanatomical structure of the choroid plexus in addition to its function and embryology. The literature was searched for articles and textbooks for data related to the history, anatomy, physiology, histology, embryology, potential functions, and surgical implications of the choroid plexus. All were gathered and summarized comprehensively. We summarize the literature regarding the choroid plexus and its surgical implications.
Evidence for social working memory from a parametric functional MRI study.
Meyer, Meghan L; Spunt, Robert P; Berkman, Elliot T; Taylor, Shelley E; Lieberman, Matthew D
2012-02-07
Keeping track of various amounts of social cognitive information, including people's mental states, traits, and relationships, is fundamental to navigating social interactions. However, to date, no research has examined which brain regions support variable amounts of social information processing ("social load"). We developed a social working memory paradigm to examine the brain networks sensitive to social load. Two networks showed linear increases in activation as a function of increasing social load: the medial frontoparietal regions implicated in social cognition and the lateral frontoparietal system implicated in nonsocial forms of working memory. Of these networks, only load-dependent medial frontoparietal activity was associated with individual differences in social cognitive ability (trait perspective-taking). Although past studies of nonsocial load have uniformly found medial frontoparietal activity decreases with increasing task demands, the current study demonstrates these regions do support increasing mental effort when such effort engages social cognition. Implications for the etiology of clinical disorders that implicate social functioning and potential interventions are discussed.
Field theoretic perspectives of the Wigner function formulation of the chiral magnetic effect
NASA Astrophysics Data System (ADS)
Wu, Yan; Hou, De-fu; Ren, Hai-cang
2017-11-01
We assess the applicability of the Wigner function formulation in its present form to the chiral magnetic effect and note some issues regarding the conservation and the consistency of the electric current in the presence of an inhomogeneous and time-dependent axial chemical potential. The problems are rooted in the ultraviolet divergence of the underlying field theory associated with the axial anomaly and can be fixed with the Pauli-Villars regularization of the Wigner function. The chiral magnetic current with a nonconstant axial chemical potential is calculated with the regularized Wigner function and the phenomenological implications are discussed.
Baxter, David
2010-06-01
Newborn infants, particularly those born prematurely are at increased risk of infections, including vaccine preventable ones, resulting in an increased morbidity and mortality risk. Defects associated with higher mortality may involve external barriers and the innate and adaptive systems. The available evidence suggests a complex situation that ranges from pathogen/immunogen non-responsiveness to fully mature adult-equivalent functionality depending on both host and vaccine characteristics. This review considers potential qualitative and quantitative differences with respect to immune defences between premature/term infants and adults and evaluates implications of such differences for immunization outcomes.
Long non-coding RNAs in hepatocellular carcinoma: Potential roles and clinical implications
Niu, Zhao-Shan; Niu, Xiao-Jun; Wang, Wen-Hong
2017-01-01
Long non-coding RNAs (lncRNAs) are a subgroup of non-coding RNA transcripts greater than 200 nucleotides in length with little or no protein-coding potential. Emerging evidence indicates that lncRNAs may play important regulatory roles in the pathogenesis and progression of human cancers, including hepatocellular carcinoma (HCC). Certain lncRNAs may be used as diagnostic or prognostic markers for HCC, a serious malignancy with increasing morbidity and high mortality rates worldwide. Therefore, elucidating the functional roles of lncRNAs in tumors can contribute to a better understanding of the molecular mechanisms of HCC and may help in developing novel therapeutic targets. In this review, we summarize the recent progress regarding the functional roles of lncRNAs in HCC and explore their clinical implications as diagnostic or prognostic biomarkers and molecular therapeutic targets for HCC. PMID:28932078
AMPK-mediated regulation of neuronal metabolism and function in brain diseases.
Liu, Yu-Ju; Chern, Yijuang
2015-01-01
The AMP-activated protein kinase (AMPK) is a serine/threonine kinase that functions as a key energy sensor in a wide variety of tissues. This kinase has been a major drug target for metabolic diseases (e.g., type 2 diabetes) and cancers. For example, metformin (an activator of AMPK) is a first-line diabetes drug that protects against cancers. Abnormal regulation of AMPK has been implicated in several brain diseases, including Alzheimer's disease, Parkinson's disease, Huntington's disease, amyotrophic lateral sclerosis, and stroke. Given the emerging importance of neurodegenerative diseases in our aging societies, this review features the recent studies that have delineated the functions of AMPK in brain diseases and discusses their potential clinical implications or roles as drug targets in brain diseases.
Potential mechanisms for chemotherapy-induced impairments in cognitive function.
Jansen, Catherine; Miaskowski, Christine; Dodd, Marilyn; Dowling, Glenna; Kramer, Joel
2005-11-03
To review the domains of cognitive function and their corresponding neuroanatomic structures as well as present current evidence for neurotoxicity associated with specific chemotherapeutic agents and potential mechanisms for chemotherapy-induced cognitive impairments. Published research articles, review articles, and textbooks. Chemotherapy does not appear to cross the blood-brain barrier when given in standard doses; however, many chemotherapy drugs have the potential to cause cognitive impairments through more than one mechanism. In addition, patient factors may be protective or place individuals at higher risk for cognitive impairments. Although evidence of chemotherapy-induced impairments in cognitive function exists, no clinical studies have attempted to elucidate the mechanisms for chemotherapy-induced impairments in cognitive function. In addition, further studies are needed to determine predictive factors, potential biomarkers, and relevant assessment parameters. The ability to identify high-risk patients has important implications for practice in regard to informed consent, patient education about the effects of treatment, and preventive strategies.
E.S. Euskirchen; A.D. McGuire; F.S. III Chapin; S. Yi; C.C. Thompson
2009-01-01
Assessing potential future changes in arctic and boreal plant species productivity, ecosystem composition, and canopy complexity is essential for understanding environmental responses under expected altered climate forcing. We examined potential changes in the dominant plant functional types (PFTs) of the sedge tundra, shrub tundra, and boreal forest ecosystems in...
Intermuscular Fat: A Review of the Consequences and Causes
Marcus, Robin L.; LaStayo, Paul C.; Ryan, Alice S.
2014-01-01
Muscle's structural composition is an important factor underlying muscle strength and physical function in older adults. There is an increasing amount of research to support the clear disassociation between the loss of muscle lean tissue mass and strength with aging. This disassociation implies that factors in addition to lean muscle mass are responsible for the decreases in strength and function seen with aging. Intermuscular adipose tissue (IMAT) is a significant predictor of both muscle function and mobility function in older adults and across a wide variety of comorbid conditions such as stroke, spinal cord injury, diabetes, and COPD. IMAT is also implicated in metabolic dysfunction such as insulin resistance. The purpose of this narrative review is to provide a review of the implications of increased IMAT levels in metabolic, muscle, and mobility function. Potential treatment options to mitigate increasing levels of IMAT will also be discussed. PMID:24527032
Sequence patterns mediating functions of disordered proteins.
Exarchos, Konstantinos P; Kourou, Konstantina; Exarchos, Themis P; Papaloukas, Costas; Karamouzis, Michalis V; Fotiadis, Dimitrios I
2015-01-01
Disordered proteins lack specific 3D structure in their native state and have been implicated with numerous cellular functions as well as with the induction of severe diseases, e.g., cardiovascular and neurodegenerative diseases as well as diabetes. Due to their conformational flexibility they are often found to interact with a multitude of protein molecules; this one-to-many interaction which is vital for their versatile functioning involves short consensus protein sequences, which are normally detected using slow and cumbersome experimental procedures. In this work we exploit information from disorder-oriented protein interaction networks focused specifically on humans, in order to assemble, by means of overrepresentation, a set of sequence patterns that mediate the functioning of disordered proteins; hence, we are able to identify how a single protein achieves such functional promiscuity. Next, we study the sequential characteristics of the extracted patterns, which exhibit a striking preference towards a very limited subset of amino acids; specifically, residues leucine, glutamic acid, and serine are particularly frequent among the extracted patterns, and we also observe a nontrivial propensity towards alanine and glycine. Furthermore, based on the extracted patterns we set off to infer potential functional implications in order to verify our findings and potentially further extrapolate our knowledge regarding the functioning of disordered proteins. We observe that the extracted patterns are primarily involved with regulation, binding and posttranslational modifications, which constitute the most prominent functions of disordered proteins.
Suetterlin, Karen Joan; Sayer, Avan Aihie
2014-05-01
Proprioception, the sense of where one is in space, is essential for effective interaction with the environment. A lack of or reduction in proprioceptive acuity has been directly correlated with falls and with reduced functional independence in older people. Proprioceptive losses have also been shown to negatively correlate with functional recovery post stroke and play a significant role in other conditions such as Parkinson's disease. However, despite its central importance to many geriatric syndromes, the clinical assessment of proprioception has remained remarkably static. We look at approaches to the clinical assessment of proprioception, changes in proprioception across the life course, functional implications of proprioception in health and disease and the potential for targeted interventions in the future such as joint taping, and proprioception-specific rehabilitation and footwear.
Functional Imaging for Prostate Cancer: Therapeutic Implications
Aparici, Carina Mari; Seo, Youngho
2012-01-01
Functional radionuclide imaging modalities, now commonly combined with anatomical imaging modalities CT or MRI (SPECT/CT, PET/CT, and PET/MRI) are promising tools for the management of prostate cancer particularly for therapeutic implications. Sensitive detection capability of prostate cancer using these imaging modalities is one issue; however, the treatment of prostate cancer using the information that can be obtained from functional radionuclide imaging techniques is another challenging area. There are not many SPECT or PET radiotracers that can cover the full spectrum of the management of prostate cancer from initial detection, to staging, prognosis predictor, and all the way to treatment response assessment. However, when used appropriately, the information from functional radionuclide imaging improves, and sometimes significantly changes, the whole course of the cancer management. The limitations of using SPECT and PET radiotracers with regards to therapeutic implications are not so much different from their limitations solely for the task of detecting prostate cancer; however, the specific imaging target and how this target is reliably imaged by SPECT and PET can potentially make significant impact in the treatment of prostate cancer. Finally, while the localized prostate cancer is considered manageable, there is still significant need for improvement in noninvasive imaging of metastatic prostate cancer, in treatment guidance, and in response assessment from functional imaging including radionuclide-based techniques. In this review article, we present the rationale of using functional radionuclide imaging and the therapeutic implications for each of radionuclide imaging agent that have been studied in human subjects. PMID:22840598
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matthew Mihelic, F.
2010-12-22
Nucleic acids theoretically possess a Szilard engine function that can convert the energy associated with the Shannon entropy of molecules for which they have coded recognition, into the useful work of geometric reconfiguration of the nucleic acid molecule. This function is logically reversible because its mechanism is literally and physically constructed out of the information necessary to reduce the Shannon entropy of such molecules, which means that this information exists on both sides of the theoretical engine, and because information is retained in the geometric degrees of freedom of the nucleic acid molecule, a quantum gate is formed through whichmore » multi-state nucleic acid qubits can interact. Entangled biophotons emitted as a consequence of symmetry breaking nucleic acid Szilard engine (NASE) function can be used to coordinate relative positioning of different nucleic acid locations, both within and between cells, thus providing the potential for quantum coherence of an entire biological system. Theoretical implications of understanding biological systems as such 'quantum adaptive systems' include the potential for multi-agent based quantum computing, and a better understanding of systemic pathologies such as cancer, as being related to a loss of systemic quantum coherence.« less
NASA Astrophysics Data System (ADS)
Matthew Mihelic, F.
2010-12-01
Nucleic acids theoretically possess a Szilard engine function that can convert the energy associated with the Shannon entropy of molecules for which they have coded recognition, into the useful work of geometric reconfiguration of the nucleic acid molecule. This function is logically reversible because its mechanism is literally and physically constructed out of the information necessary to reduce the Shannon entropy of such molecules, which means that this information exists on both sides of the theoretical engine, and because information is retained in the geometric degrees of freedom of the nucleic acid molecule, a quantum gate is formed through which multi-state nucleic acid qubits can interact. Entangled biophotons emitted as a consequence of symmetry breaking nucleic acid Szilard engine (NASE) function can be used to coordinate relative positioning of different nucleic acid locations, both within and between cells, thus providing the potential for quantum coherence of an entire biological system. Theoretical implications of understanding biological systems as such "quantum adaptive systems" include the potential for multi-agent based quantum computing, and a better understanding of systemic pathologies such as cancer, as being related to a loss of systemic quantum coherence.
Miranda T. Curzon; Anthony W. D' Amato; Brian J. Palik
2014-01-01
Understanding the effects of management on forest structure and function is increasingly important in light of projected increases in both natural and anthropogenic disturbance severity and frequency with global environmental change. We examined potential impacts of the procurement of forest-derived bioenergy, a change in land use that has been suggested as a climate...
2011-04-01
activation still needs to be determined (Strotmann et al. 2000). 7.2.4 The Use of MS Enzyme Inhibitors A further strategy for implicating potential MS...invasiveness and metastatic potential . 1.1 Use patch-clamp/pressure clamp techniques, confocal immunofluorescence, Westerns and surface biotinylation...9. Maroto, R. Kurosky, A. Hamill, O.P. Expression and function of canonical transient recptor potential channels in human prostate tumor cells
Evidenced-based review of clinical studies on periodontics.
2009-08-01
Periodontal diseases have several implications for the practice of endodontics. First, advanced periodontitis often has direct implications for the long-term prognosis of the case and requires careful evaluation and coordinated treatment of both the periodontic and endodontic diseases. Second, the potential for functional interactions between odontogenic pathoses and marginal periodontitis requires careful collection of clinical observations and monitoring the outcome of various treatments. In this section, we provide an analysis of recent clinical studies in this area.
Fazal, Shaline V; Gomez-Sanchez, Jose A; Wagstaff, Laura J; Musner, Nicolo; Otto, Georg; Janz, Martin; Mirsky, Rhona; Jessen, Kristján R
2017-12-13
Schwann cell c-Jun is implicated in adaptive and maladaptive functions in peripheral nerves. In injured nerves, this transcription factor promotes the repair Schwann cell phenotype and regeneration and promotes Schwann-cell-mediated neurotrophic support in models of peripheral neuropathies. However, c-Jun is associated with tumor formation in some systems, potentially suppresses myelin genes, and has been implicated in demyelinating neuropathies. To clarify these issues and to determine how c-Jun levels determine its function, we have generated c-Jun OE/+ and c-Jun OE/OE mice with graded expression of c-Jun in Schwann cells and examined these lines during development, in adulthood, and after injury using RNA sequencing analysis, quantitative electron microscopic morphometry, Western blotting, and functional tests. Schwann cells are remarkably tolerant of elevated c-Jun because the nerves of c-Jun OE/+ mice, in which c-Jun is elevated ∼6-fold, are normal with the exception of modestly reduced myelin thickness. The stronger elevation of c-Jun in c-Jun OE/OE mice is, however, sufficient to induce significant hypomyelination pathology, implicating c-Jun as a potential player in demyelinating neuropathies. The tumor suppressor P19 ARF is strongly activated in the nerves of these mice and, even in aged c-Jun OE/OE mice, there is no evidence of tumors. This is consistent with the fact that tumors do not form in injured nerves, although they contain proliferating Schwann cells with strikingly elevated c-Jun. Furthermore, in crushed nerves of c-Jun OE/+ mice, where c-Jun levels are overexpressed sufficiently to accelerate axonal regeneration, myelination and function are restored after injury. SIGNIFICANCE STATEMENT In injured and diseased nerves, the transcription factor c-Jun in Schwann cells is elevated and variously implicated in controlling beneficial or adverse functions, including trophic Schwann cell support for neurons, promotion of regeneration, tumorigenesis, and suppression of myelination. To analyze the functions of c-Jun, we have used transgenic mice with graded elevation of Schwann cell c-Jun. We show that high c-Jun elevation is a potential pathogenic mechanism because it inhibits myelination. Conversely, we did not find a link between c-Jun elevation and tumorigenesis. Modest c-Jun elevation, which is beneficial for regeneration, is well tolerated during Schwann cell development and in the adult and is compatible with restoration of myelination and nerve function after injury. Copyright © 2017 Fazal, Gomez-Sanchez et al.
Fazal, Shaline V.; Wagstaff, Laura J.; Musner, Nicolo; Janz, Martin
2017-01-01
Schwann cell c-Jun is implicated in adaptive and maladaptive functions in peripheral nerves. In injured nerves, this transcription factor promotes the repair Schwann cell phenotype and regeneration and promotes Schwann-cell-mediated neurotrophic support in models of peripheral neuropathies. However, c-Jun is associated with tumor formation in some systems, potentially suppresses myelin genes, and has been implicated in demyelinating neuropathies. To clarify these issues and to determine how c-Jun levels determine its function, we have generated c-Jun OE/+ and c-Jun OE/OE mice with graded expression of c-Jun in Schwann cells and examined these lines during development, in adulthood, and after injury using RNA sequencing analysis, quantitative electron microscopic morphometry, Western blotting, and functional tests. Schwann cells are remarkably tolerant of elevated c-Jun because the nerves of c-Jun OE/+ mice, in which c-Jun is elevated ∼6-fold, are normal with the exception of modestly reduced myelin thickness. The stronger elevation of c-Jun in c-Jun OE/OE mice is, however, sufficient to induce significant hypomyelination pathology, implicating c-Jun as a potential player in demyelinating neuropathies. The tumor suppressor P19ARF is strongly activated in the nerves of these mice and, even in aged c-Jun OE/OE mice, there is no evidence of tumors. This is consistent with the fact that tumors do not form in injured nerves, although they contain proliferating Schwann cells with strikingly elevated c-Jun. Furthermore, in crushed nerves of c-Jun OE/+ mice, where c-Jun levels are overexpressed sufficiently to accelerate axonal regeneration, myelination and function are restored after injury. SIGNIFICANCE STATEMENT In injured and diseased nerves, the transcription factor c-Jun in Schwann cells is elevated and variously implicated in controlling beneficial or adverse functions, including trophic Schwann cell support for neurons, promotion of regeneration, tumorigenesis, and suppression of myelination. To analyze the functions of c-Jun, we have used transgenic mice with graded elevation of Schwann cell c-Jun. We show that high c-Jun elevation is a potential pathogenic mechanism because it inhibits myelination. Conversely, we did not find a link between c-Jun elevation and tumorigenesis. Modest c-Jun elevation, which is beneficial for regeneration, is well tolerated during Schwann cell development and in the adult and is compatible with restoration of myelination and nerve function after injury. PMID:29109239
Gut microbiome can control antitumor immune function in liver
An NCI study in mice that found a connection between gut bacteria and antitumor immune responses in the liver has implications for understanding mechanisms that lead to liver cancer and for potential treatments. The study was published in Science.
Albumin in chronic liver disease: structure, functions and therapeutic implications.
Spinella, Rosaria; Sawhney, Rohit; Jalan, Rajiv
2016-01-01
Human serum albumin is a critical plasma protein produced by the liver with a number of accepted clinical indications in chronic liver disease including management of circulatory and renal dysfunction in patients with ascites. Advanced cirrhosis is characterised by reduced albumin concentration as well as impaired albumin function as a result of specific structural changes and oxidative damage. Traditionally, the biologic and therapeutic role of albumin in liver disease was attributed to its oncotic effects but it is now understood that albumin has a wide range of other important physiologic functions such as immunomodulation, endothelial stabilisation, antioxidant effects and binding multiple drugs, toxins and other molecules. This review discusses the multifunctional properties of albumin and, in particular, the biologic and clinical implications of structural and functional changes of albumin that are associated with cirrhosis. Based on these insights, we explore the current and potential future therapeutic uses of albumin in liver disease.
Jeltsch-David, Hélène; Koenig, Julie; Cassel, Jean-Christophe
2008-12-16
Cholinergic systems were linked to cognitive processes like attention and memory. Other neurotransmitter systems having minor influence on cognitive functions - as shown by the weakness of the effects of their selective lesions - modulate cholinergic functions. The serotonergic system is such a system. Conjoined functional changes in cholinergic and serotonergic systems may have marked cognitive consequences [Cassel JC, Jeltsch H. Serotoninergic modulation of cholinergic function in the central nervous system: cognitive implications. Neuroscience 1995;69(1):1-41; Steckler T, Sahgal A. The role of serotoninergic-cholinergic interactions in the mediation of cognitive behaviour. Behav Brain Res 1995;67:165-99]. A crucial issue in that concern is the identification of the neuroanatomical and neuropharmacological substrates where functional effects of serotonergic/cholinergic interactions originate. Approaches relying on lesions and intracerebral cell grafting, on systemic drug-cocktail injections, or even on intracerebral drug infusions represent the main avenues on which our knowledge about the role of serotonergic/cholinergic interactions has progressed. The present review will visit some of these avenues and discuss their contribution to what is currently known on the potential or established implication(s) into memory functions of serotonergic/cholinergic interactions. It will then focus on a brain region and a neuropharmacological substrate that have been poorly studied as regards serotonergic modulation of memory functions, namely the medial septum and its 5-HT(1A) receptors. Based on recent findings of our laboratory, we suggest that these receptors, located on both cholinergic and GABAergic septal neurons, take part in a mechanism that controls encoding, to some extent consolidation, but not retrieval, of hippocampal-dependent memories. This control, however, does not occur by the way of an exclusive action of serotonin on cholinergic neurons.
Wei, Feng; Yan, Li-Min; Su, Tao; He, Na; Lin, Zhi-Jian; Wang, Jie; Shi, Yi-Wu; Yi, Yong-Hong; Liao, Wei-Ping
2017-08-01
Ion channels are crucial in the generation and modulation of excitability in the nervous system and have been implicated in human epilepsy. Forty-one epilepsy-associated ion channel genes and their mutations are systematically reviewed. In this paper, we analyzed the genotypes, functional alterations (funotypes), and phenotypes of these mutations. Eleven genes featured loss-of-function mutations and six had gain-of-function mutations. Nine genes displayed diversified funotypes, among which a distinct funotype-phenotype correlation was found in SCN1A. These data suggest that the funotype is an essential consideration in evaluating the pathogenicity of mutations and a distinct funotype or funotype-phenotype correlation helps to define the pathogenic potential of a gene.
Mezzalira, Jean C; Bonnet, Olivier J F; Carvalho, Paulo C de F; Fonseca, Lidiane; Bremm, Carolina; Mezzalira, Carlos C; Laca, Emilio A
2017-09-01
The functional response (i.e. the relationship between consumers' intake rate and resource density) is central in plant-herbivore interactions. Its shape and the biological processes leading to it have significant implications for both foraging theory and ecology of grazing systems. A type IV functional response (i.e. dome-shaped relationship) of short-term intake rate of dry matter (intake while grazing) has rarely been reported for large herbivores and the conditions that can lead to it are poorly understood. We report a type IV functional response observed in heifers grazing monocultures of Cynodon sp. and Avena strigosa. The mechanisms and consequences of this type of functional response for grazed system dynamics are discussed. Intake rate was higher at intermediate than at short or tall sward heights in both grass species. The type IV functional response resulted from changes in bite mass instead of a longer time needed to encounter and process bites. Thus, the decrease of intake rate of dry matter in tall swards is not explained by a shift from process 3 (potential bites are concentrated and apparent) to process 2 (potential bites are apparent but dispersed, Spalinger & Hobbs 1992). Bite mass was smaller in tall than in intermediate swards due to a reduction of bite volume possibly caused by the greater proportion of stem and sheath acting as a physical barrier to bite formation. It is generally accepted that potential bites are abundant and apparent in most grassland and meadow systems, as they were in the present experiments. Therefore, a type IV response of intake rate not directly related to digestive constraints may determine the dynamics of intake and defoliation under a much larger set of conditions than previously thought. These results have implications for foraging theory and stability of grazing systems. For example, if animals prefer patches of intermediate stature that yield the highest intake rate, grazing should lead to the widely observed bimodal distribution of plant mass per unit area, even when tall patches are not of significantly lower digestive quality than the pasture average. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.
The Role of Exercise in Cardiac Aging: From Physiology to Molecular Mechanisms
Roh, Jason; Rhee, James; Chaudhari, Vinita; Rosenzweig, Anthony
2015-01-01
Aging induces structural and functional changes in the heart that are associated with increased risk of cardiovascular disease and impaired functional capacity in the elderly. Exercise is a diagnostic and therapeutic tool, with the potential to provide insights into clinical diagnosis and prognosis, as well as the molecular mechanisms by which aging influences cardiac physiology and function. In this review, we first provide an overview of how aging impacts the cardiac response to exercise and the implications this has for functional capacity in older adults. We then review the underlying molecular mechanisms by which cardiac aging contributes to exercise intolerance, and conversely how exercise training can potentially modulate aging phenotypes in the heart. Finally, we highlight the potential use of these exercise models to complement models of disease in efforts to uncover new therapeutic targets to prevent or treat heart disease in the aging population. PMID:26838314
The Role of Exercise in Cardiac Aging: From Physiology to Molecular Mechanisms.
Roh, Jason; Rhee, James; Chaudhari, Vinita; Rosenzweig, Anthony
2016-01-22
Aging induces structural and functional changes in the heart that are associated with increased risk of cardiovascular disease and impaired functional capacity in the elderly. Exercise is a diagnostic and therapeutic tool, with the potential to provide insights into clinical diagnosis and prognosis, as well as the molecular mechanisms by which aging influences cardiac physiology and function. In this review, we first provide an overview of how aging impacts the cardiac response to exercise, and the implications this has for functional capacity in older adults. We then review the underlying molecular mechanisms by which cardiac aging contributes to exercise intolerance, and conversely how exercise training can potentially modulate aging phenotypes in the heart. Finally, we highlight the potential use of these exercise models to complement models of disease in efforts to uncover new therapeutic targets to prevent or treat heart disease in the aging population. © 2016 American Heart Association, Inc.
Functional disability in paediatric patients with recurrent abdominal pain.
Wendland, M; Jackson, Y; Stokes, L D
2010-07-01
Recurrent abdominal pain (RAP) is common in childhood, affecting approximately 12% of children and adolescents. Children with RAP tend to experience impairments in functioning, such as increased school absences, anxiety and depression. The current study investigated the potential influences on the relation between functional disability and RAP in 100 school-aged children. A series of hierarchical regression analyses were conducted to test two models: main effects and moderation of the relation between abdominal pain symptoms, child anxiety, child depression, maternal emotional distress, maternal encouragement of child illness behaviour and functional disability. The results indicated support for abdominal pain symptoms and child depression in predicting functional disability. The results also indicated that child anxiety and child depression each moderated the relation between pain symptoms and functional disability. Implications of the findings are discussed in terms of potential influences on the development of functional disability in youth.
Steinman, Bernard A; Allen, Susan M; Chen, Jie; Pynoos, Jon
2015-02-01
To test whether limitations in mobility and large-muscle functioning mediate self-reported vision status to increase fall risk among respondents age 65 and above. This study used two waves from the Health and Retirement Study. We conducted binary logistic and negative binomial regression analyses to test indirect paths leading from self-reported vision status to falls, via indices of mobility and large-muscle functioning. Limited evidence was found for a mediating effect among women; however, large-muscle groups were implicated as partially mediating risk factors for falls among men with fair self-reported vision status. Implications of these findings are discussed including the need for prioritizing improved muscle strength of older men and women with poor vision as a preventive measure against falls. © The Author(s) 2014.
Sokhi, Upneet K.; Bacolod, Manny D.; Dasgupta, Santanu; Emdad, Luni; Das, Swadesh K.; Dumur, Catherine I.; Miles, Michael F.; Sarkar, Devanand; Fisher, Paul B.
2013-01-01
Human Polynucleotide Phosphorylase (hPNPaseold-35 or PNPT1) is an evolutionarily conserved 3′→5′ exoribonuclease implicated in the regulation of numerous physiological processes including maintenance of mitochondrial homeostasis, mtRNA import and aging-associated inflammation. From an RNase perspective, little is known about the RNA or miRNA species it targets for degradation or whose expression it regulates; except for c-myc and miR-221. To further elucidate the functional implications of hPNPaseold-35 in cellular physiology, we knocked-down and overexpressed hPNPaseold-35 in human melanoma cells and performed gene expression analyses to identify differentially expressed transcripts. Ingenuity Pathway Analysis indicated that knockdown of hPNPaseold-35 resulted in significant gene expression changes associated with mitochondrial dysfunction and cholesterol biosynthesis; whereas overexpression of hPNPaseold-35 caused global changes in cell-cycle related functions. Additionally, comparative gene expression analyses between our hPNPaseold-35 knockdown and overexpression datasets allowed us to identify 77 potential “direct” and 61 potential “indirect” targets of hPNPaseold-35 which formed correlated networks enriched for cell-cycle and wound healing functional association, respectively. These results provide a comprehensive database of genes responsive to hPNPaseold-35 expression levels; along with the identification new potential candidate genes offering fresh insight into cellular pathways regulated by PNPT1 and which may be used in the future for possible therapeutic intervention in mitochondrial- or inflammation-associated disease phenotypes. PMID:24143183
Cancer Stem Cells (CSCs) and Mechanisms of Their Regulation: Implications for Cancer Therapy
Bao, Bin; Ahmad, Aamir; Azmi, Asfar S.; Ali, Shadan; Sarkar, Fazlul H.
2013-01-01
The identification of small subpopulations of cancer stem cells (CSCs) from blood mononuclear cells in human acute myeloid leukemia (AML) in 1997 was the landmark observation for recognizing the potential role of CSCs in tumor aggressiveness. Two critical properties contribute to the functional role of CSCs in the establishment and recurrence of cancerous tumors: their self-renewal capacity and their potential to differentiate into unlimited heterogeneous populations of cancer cells. These findings suggest that CSCs may represent novel therapeutic targets for the treatment and/or prevention of tumor progression as they appear to be involved in cell migration, invasion, metastasis, and treatment resistance, all of which lead to poor clinical outcomes. The identification of CSC-specific markers, the isolation and characterization of CSCs from malignant tissues, and targeting strategies for the destruction of CSCs provides a novel opportunity for cancer research. Described in this overview is the potential implication of several common CSC markers in the identification of CSC subpopulation restricted to common malignant diseases e.g., leukemia, breast, prostate, pancreatic and lung cancers. The role of microRNAs (miRNAs) in the regulation of CSC function is also discussed, as are several methods commonly used in CSC research. The potential role of the anti-diabetic drug metformin that has been shown to have effects on CSCs, and known function as an anti-tumor agent, provides an example of this new class of chemotherapeutics. PMID:23744710
Tam, Bryan Wei Hoe; Lo, Dana Rui Ting; Seah, Daniel Wen Hao; Lee, Jun Xian; Foo, Zann Fang Ying; Poh, Zoe Yu Yah; Thong, Fionna Xiu Jun; Sim, Sam Kim Yang; Chee, Chew Sim
2017-01-01
There is a paucity of research available on the effect of mindfulness on cognitive function. However, the topic has recently gained more attention due to the ageing population in Singapore, catalysed by recent findings on brain function and cellular ageing. Recognising the potential benefits of practising mindfulness, we aimed to develop a localised, self-training mindfulness programme, guided by expert practitioners and usability testing, for older Singaporean adults. This was followed by a pilot study to examine the potential cognitive benefits and feasibility of this self-training programme for the cognitive function of older adults in Singapore. We found that the results from the pilot study were suggestive but inconclusive, and thus, merit further investigation. PMID:27868134
Tam, Bryan Wei Hoe; Lo, Dana Rui Ting; Seah, Daniel Wen Hao; Lee, Jun Xian; Foo, Zann Fang Ying; Poh, Zoe Yu Yah; Thong, Fionna Xiu Jun; Sim, Sam Kim Yang; Chee, Chew Sim
2017-03-01
There is a paucity of research available on the effect of mindfulness on cognitive function. However, the topic has recently gained more attention due to the ageing population in Singapore, catalysed by recent findings on brain function and cellular ageing. Recognising the potential benefits of practising mindfulness, we aimed to develop a localised, self-training mindfulness programme, guided by expert practitioners and usability testing, for older Singaporean adults. This was followed by a pilot study to examine the potential cognitive benefits and feasibility of this self-training programme for the cognitive function of older adults in Singapore. We found that the results from the pilot study were suggestive but inconclusive, and thus, merit further investigation. Copyright: © Singapore Medical Association.
Woodle, E S; Rothstein, D M
2015-01-01
B cells play a complex role in the immune response. In addition to giving rise to plasma cells (PCs) and promoting T cell responses via antigen presentation, they perform immunoregulatory functions. This knowledge has created concerns regarding nonspecific B cell depletional therapy because of the potential to paradoxically augment immune responses. Recent studies now indicate that PCs have immune functions beyond immunoglobulin synthesis. Evidence for a new role for PCs as potent regulatory cells (via IL-10 and IL-35 production) is discussed including the implications for PC-targeted therapies currently being developed for clinical transplantation. © Copyright 2014 The American Society of Transplantation and the American Society of Transplant Surgeons.
ERIC Educational Resources Information Center
Fontaine, Joseph J.; Stier, Samuel C.; Maggio, Melissa L.; Decker, Karie L.
2007-01-01
Students can gain an appreciation for the structure and function of local environments by studying the potential impacts of small changes in local microclimate on plant distribution. The concept of microclimate is easy for students to comprehend, simple to measure, exists in all schoolyards, and has important and tangible ecological implications.…
Dietary supplementation with coffee improves motor and cognitive performance in aged rats
USDA-ARS?s Scientific Manuscript database
Polyphenols found in fruits and nuts have anti-inflammatory properties that may provide protection against the decline of cognitive, motor and neuronal function in senescence. The presence of a number of bioactive compounds (e.g., polyphenols) implicates coffee as a potential nutritional therapeutic...
Neuropsychology of Child Maltreatment and Implications for School Psychologists
ERIC Educational Resources Information Center
Davis, Andrew S.; Moss, Lauren E.; Nogin, Margarita M.; Webb, Nadia Elizabeth
2015-01-01
Child maltreatment has the potential to alter a child's neurodevelopmental trajectory and substantially increase the risk of later psychiatric disorders, as well as to deleteriously impact neurocognitive functioning throughout the lifespan. Child maltreatment has been linked to multiple domains of neurocognitive impairment, including…
NASA Technical Reports Server (NTRS)
Leventis, Nicholas; Yang, Jinua; Fabrizio,Even F.; Rawashdeh, Abdel-Monem M.; Oh, Woon Su; Sotiriou-Leventis, Chariklia
2004-01-01
Dendrimers are self-repeating globular branched star molecules, whose fractal structure continues to fascinate, challenge, and inspire. Functional dendrimers may incorporate redox centers, and potential applications include antennae molecules for light harvesting, sensors, mediators, and artificial biomolecules. We report the synthesis and redox properties of four star systems incorporating the 4-benzoyl-N-alkylpyridinium cation; the redox potential varies along the branches but remains constant at fixed radii. Bulk electrolysis shows that at a semi-infinite time scale all redox centers are electrochemically accessible. However, voltammetric analysis (cyclic voltammetry and differential pulse voltammetry) shows that on1y two of the three redox-active centers in the perimeter are electrochemically accessible during potential sweeps as slow as 20 mV/s and as fast as 10 V/s. On the contrary, both redox centers along branches are accessible electrochemically within the same time frame. These results are explained in terms of slow through-space charge transfer and the globular 3-D folding of the molecules and are discussed in terms of their implications on the design of efficient redox functional dendrimers.
Poggio, Emilio D; Braun, William E; Davis, Connie
2009-10-01
Living kidney donor transplantation is now a common treatment for ESRD because it provides excellent outcomes to transplant recipients and is considered a safe procedure for prospective donors. The short- and long-term safety of prospective donors is paramount to the continued success of this procedure. Whereas the initial experiences with living kidney donors mostly included the healthiest, the increase in the need for organs and the changing demographic characteristics of the general population have subtly reshaped the suitability for donation. Kidney function assessment is a critical component of the evaluation of prospective donors; therefore, special emphasis is usually placed on this aspect of the evaluation. At the same time, consideration of kidney function after donation is important because it assists with the determination of renal health in donors. This review summarizes the process of predonation kidney function assessment, determinants of pre- and postdonation renal function, and, importantly, the potential implications of kidney function to the long-term outcomes of kidney donors.
The biology, function and clinical implications of exosomes in lung cancer.
Zhou, Li; Lv, Tangfeng; Zhang, Qun; Zhu, Qingqing; Zhan, Ping; Zhu, Suhua; Zhang, Jianya; Song, Yong
2017-10-28
Exosomes are 30-100 nm small membrane vesicles of endocytic origin that are secreted by all types of cells, and can also be found in various body fluids. Increasing evidence implicates that exosomes confer stability and can deliver their cargos such as proteins and nucleic acids to specific cell types, which subsequently serve as important messengers and carriers in lung carcinogenesis. Here, we describe the biogenesis and components of exosomes mainly in lung cancer, we summarize their function in lung carcinogenesis (epithelial mesenchymal transition, oncogenic cell transformation, angiogenesis, metastasis and immune response in tumor microenvironment), and importantly we focus on the clinical potential of exosomes as biomarkers and therapeutics in lung cancer. In addition, we also discuss current challenges that might impede the clinical use of exosomes. Further studies on the functional roles of exosomes in lung cancer requires thorough research. Copyright © 2017 Elsevier B.V. All rights reserved.
Integrating research, clinical care, and education in academic health science centers.
King, Gillian; Thomson, Nicole; Rothstein, Mitchell; Kingsnorth, Shauna; Parker, Kathryn
2016-10-10
Purpose One of the major issues faced by academic health science centers (AHSCs) is the need for mechanisms to foster the integration of research, clinical, and educational activities to achieve the vision of evidence-informed decision making (EIDM) and optimal client care. The paper aims to discuss this issue. Design/methodology/approach This paper synthesizes literature on organizational learning and collaboration, evidence-informed organizational decision making, and learning-based organizations to derive insights concerning the nature of effective workplace learning in AHSCs. Findings An evidence-informed model of collaborative workplace learning is proposed to aid the alignment of research, clinical, and educational functions in AHSCs. The model articulates relationships among AHSC academic functions and sub-functions, cross-functional activities, and collaborative learning processes, emphasizing the importance of cross-functional activities in enhancing collaborative learning processes and optimizing EIDM and client care. Cross-functional activities involving clinicians, researchers, and educators are hypothesized to be a primary vehicle for integration, supported by a learning-oriented workplace culture. These activities are distinct from interprofessional teams, which are clinical in nature. Four collaborative learning processes are specified that are enhanced in cross-functional activities or teamwork: co-constructing meaning, co-learning, co-producing knowledge, and co-using knowledge. Practical implications The model provides an aspirational vision and insight into the importance of cross-functional activities in enhancing workplace learning. The paper discusses the conceptual and empirical basis to the model, its contributions and limitations, and implications for AHSCs. Originality/value The model's potential utility for health care is discussed, with implications for organizational culture and the promotion of cross-functional activities.
Ozone is a ubiquitous smog-associated photochemical oxidant with deleterious health effects. While most of the adverse effects described to date involve the respiratory system (i.e, decrements in lung function, airway injury and inflammation, exacerbation of asthma, and compromis...
Biologic Activity of Lycopene Metabolites: Implications for Cancer Prevention
USDA-ARS?s Scientific Manuscript database
While early studies focused on the potential roles in health and disease of provitamin A carotenoids, such as beta-carotene, research over the past decade has provided a framework for our understanding of the functions of non-provitamin A carotenoids such as lycopene, especially in regards to its as...
Sokol, Kelsey; Tremblay, Douglas; Bhalla, Sheena; Rampal, Raajit; Mascarenhas, John O
2018-05-15
Myeloid malignancies arise from the acquisition of somatic mutations among various genes implicated in essential functioning of hematopoietic stem cells and progenitor cells. In this second part of our two-part review, we discuss the use of mutation profiling in the diagnosis, prognosis, and treatment of patients with myeloproliferative neoplasms and other myeloid diseases. We also discuss the entity known as clonal hematopoiesis of indeterminate potential, awareness of which is a result of the increasing availability and improved quality of mutation profiling.
Probiotics, prebiotics, and the host microbiome: the science of translation
Petschow, Bryon; Doré, Joël; Hibberd, Patricia; Dinan, Timothy; Reid, Gregor; Blaser, Martin; Cani, Patrice D; Degnan, Fred H; Foster, Jane; Gibson, Glenn; Hutton, John; Klaenhammer, Todd R; Ley, Ruth; Nieuwdorp, Max; Pot, Bruno; Relman, David; Serazin, Andrew; Sanders, Mary Ellen
2013-01-01
Recent advances in our understanding of the community structure and function of the human microbiome have implications for the potential role of probiotics and prebiotics in promoting human health. A group of experts recently met to review the latest advances in microbiota/microbiome research and discuss the implications for development of probiotics and prebiotics, primarily as they relate to effects mediated via the intestine. The goals of the meeting were to share recent advances in research on the microbiota, microbiome, probiotics, and prebiotics, and to discuss these findings in the contexts of regulatory barriers, evolving healthcare environments, and potential effects on a variety of health topics, including the development of obesity and diabetes; the long-term consequences of exposure to antibiotics early in life to the gastrointestinal (GI) microbiota; lactose intolerance; and the relationship between the GI microbiota and the central nervous system, with implications for depression, cognition, satiety, and mental health for people living in developed and developing countries. This report provides an overview of these discussions. PMID:24266656
Messing, Samuel; Chatterjee, Anjan
2011-01-01
Although a growing body of evidence suggests that noninvasive brain stimulation techniques such as transcranial magnetic stimulation and transcranial direct current stimulation have the capacity to enhance neural function in both brain-injured and neurally intact individuals, the implications of their potential use for cosmetic self-enhancement have not been fully explored. We review 3 areas in which noninvasive brain stimulation has the potential to enhance neurologic function: cognitive skills, mood, and social cognition. We then characterize the ethical problems that affect the practice of cosmetic neurology, including safety, character, justice, and autonomy, and discuss how these problems may apply to the use of noninvasive brain stimulation for self-enhancement. PMID:21220723
Hastings, Richard P; Boulton, Holly V N; Monzani, Louisa C; Tombs, Anna K H
2004-01-01
A variety of variables have been found to augment perceived social validity of behavioral interventions. In the present study, potential effects of behavioral function were evaluated. Sixty students inexperienced in work with people with mental retardation, and 60 experienced staff watched one of two carefully matched acted videos depicting self-injury maintained by attention or escape from task demands. Participants were also told whether the self-injury depicted typically led to mild or severe consequences for the person filmed. Participants rated six interventions in terms of their acceptability and effectiveness for the behavior depicted. A hierarchy of acceptability was replicated: reinforcement-based procedures were rated as more acceptable and effective. There were also effects of behavior severity and rater experience. However, few effects of behavioral function were found. Potential implications of staff undifferentiated attitudes towards functional treatments are discussed.
Rasic-Milutinovic, Z; Jovanovic, D; Bogdanovic, G; Trifunovic, J; Mutic, J
2017-02-01
Background: Besides genetic factors, it is known that some trace elements, as Selenium, Copper, and Zinc are essential for thyroid gland fuction and thyroid hormone metabolism. Moreover, there were some metals effect that suggested patterns associated with overt thyroid disease. Aim of study: Hashimoto thyroiditis (HT), chronic autoimune inflamation of thyroid gland with cosequtive hipothyroidism, is common disease in Serbia, and we thought it is worthwile to explore potential effects of essential and toxic metals and metalloides on thyroid function and ability to restore euthyroid status of them. Results: This cross-sectional, case-control, study investigated the status of essential elements (Selenium,Copper,and Zinc) and toxic metals and metalloides (Al, Cr, Mn, Co, As, Cd, Sb, Ba, Be, Pb and Ni) from the blood of 22 female, patients with Hashimoto thyroiditis and overt hypothyroidism, and compared it with those of 55 female healthy persons. We tried to establish the presence of any correlation between previous mentioned elements and thyroid function in hypothyroid patients and healthy participants. Conclusions: The results of our study suggested that the blood concentration of essential trace elements, especially the ratio of Copper, and Selenium may influence directly thyroid function in patients with HT and overt hypothyroidism.Thus, our findings may have implication to life-long substitution therapy in terms of l-thyroxine dose reduction. Furthermore, for the first time, our study shown potential toxic effect of Cadmium on thyroid function in HT patients, which may implicate the dose of l-thyroxine substitution. © Georg Thieme Verlag KG Stuttgart · New York.
Implications of contamination and surface area ratios for Langmuir probe diagnostics on CubeSats
NASA Astrophysics Data System (ADS)
Suresh, P.; Swenson, C.
2009-12-01
Theories describing the current collected by a biased probe under various conditions are necessary for such observation to be used to accurately determine plasma properties. Langmuir probes are routinely used on spacecraft to measure plasma parameters such as density, temperature, and vehicle charging. The collected current is a function of the potential between the surrounding plasma and probe surface. There have been both observations of and concepts for unaccounted variations of this potential which limit the application of Langmuir probe theory for determining plasma properties. These variations occur due to spatial variations of the work function across the probe surface due to non-uniformity of the crystalline surface properties and surface contamination of the probe. Currently we do not have theoretical expressions which consider these factors as first principles in their derivation. In the event of these surface potential variations, the analysis of the plasma using the currently available theories of the Langmuir probe yield erroneous results. We present a theory which models the current as a function of the surface potential variations. Another consideration for Langmuir probes on CubeSats is the ratio of the probe area to the return current collection area. If the area ratio is unfavorable this can also lead to erroneous results in the interpretation of observations. A mathematical formulation of the current collected by the probe for contaminated surfaces is presented and compared with data from a Langmuir probe flown on a sounding rocket mission. The implications of using Langmuir probes on CubeSats given the engineering limitations of probe cleanliness and area ratios are reviewed.
The LDL receptor gene family: signaling functions during development.
Howell, B W; Herz, J
2001-02-01
The traditional views regarding the biological functions of the low-density lipoprotein (LDL) receptor gene family have been revisited recently with new evidence that at least some of the members of this receptor family act as signal-transduction molecules. Known for their role in endocytosis, particularly of their namesake the LDLs, and for their role in the prevention of atherosclerosis, these receptors belong to an ancient family with numerous ligands, effector molecules and functions. Recent evidence implicates this family of receptors in diverse signaling pathways, long-term potentiation and neuronal degeneration.
Plasmacytoid pre-dendritic cells (pDC): from molecular pathways to function and disease association.
Alculumbre, Solana; Raieli, Salvatore; Hoffmann, Caroline; Chelbi, Rabie; Danlos, François-Xavier; Soumelis, Vassili
2018-02-19
Plasmacytoid pre-dendritic cells (pDC) are a specialized DC population with a great potential to produce large amounts of type I interferon (IFN). pDC are involved in the initiation of antiviral immune responses through their interaction with innate and adaptive immune cell populations. In a context-dependent manner, pDC activation can induce their differentiation into mature DC able to induce both T cell activation or tolerance. In this review, we described pDC functions during immune responses and their implication in the clearance or pathogenicity of human diseases during infection, autoimmunity, allergy and cancer. We discuss recent advances in the field of pDC biology and their implication for future studies. Copyright © 2018 Elsevier Ltd. All rights reserved.
Structural Priming: A Critical Review
Pickering, Martin J.; Ferreira, Victor S.
2009-01-01
Repetition is a central phenomenon of behavior, and researchers make extensive use of it to illuminate psychological functioning. In the language sciences, a ubiquitous form of such repetition is structural priming, a tendency to repeat or better process a current sentence because of its structural similarity to a previously experienced (“prime”) sentence (Bock, 1986). The recent explosion of research in structural priming has made it the dominant means of investigating the processes involved in the production (and increasingly, comprehension) of complex expressions such as sentences. This review considers its implications for the representation of syntax and the mechanisms of production, comprehension, and their relationship. It then addresses the potential functions of structural priming, before turning to its implications for first language acquisition, bilingualism, and aphasia We close with theoretical and empirical recommendations for future investigations. PMID:18444704
Phage-Phagocyte Interactions and Their Implications for Phage Application as Therapeutics
Jończyk-Matysiak, Ewa; Weber-Dąbrowska, Beata; Owczarek, Barbara; Międzybrodzki, Ryszard; Łusiak-Szelachowska, Marzanna; Łodej, Norbert; Górski, Andrzej
2017-01-01
Phagocytes are the main component of innate immunity. They remove pathogens and particles from organisms using their bactericidal tools in the form of both reactive oxygen species and degrading enzymes—contained in granules—that are potentially toxic proteins. Therefore, it is important to investigate the possible interactions between phages and immune cells and avoid any phage side effects on them. Recent progress in knowledge concerning the influence of phages on phagocytes is also important as such interactions may shape the immune response. In this review we have summarized the current knowledge on phage interactions with phagocytes described so far and their potential implications for phage therapy. The data suggesting that phage do not downregulate important phagocyte functions are especially relevant for the concept of phage therapy. PMID:28613272
Phage-Phagocyte Interactions and Their Implications for Phage Application as Therapeutics.
Jończyk-Matysiak, Ewa; Weber-Dąbrowska, Beata; Owczarek, Barbara; Międzybrodzki, Ryszard; Łusiak-Szelachowska, Marzanna; Łodej, Norbert; Górski, Andrzej
2017-06-14
Phagocytes are the main component of innate immunity. They remove pathogens and particles from organisms using their bactericidal tools in the form of both reactive oxygen species and degrading enzymes-contained in granules-that are potentially toxic proteins. Therefore, it is important to investigate the possible interactions between phages and immune cells and avoid any phage side effects on them. Recent progress in knowledge concerning the influence of phages on phagocytes is also important as such interactions may shape the immune response. In this review we have summarized the current knowledge on phage interactions with phagocytes described so far and their potential implications for phage therapy . The data suggesting that phage do not downregulate important phagocyte functions are especially relevant for the concept of phage therapy.
ERIC Educational Resources Information Center
Goldberg, Lynette R.; Heiss, Cynthia J.; White, Letitia; Kaf, Wafaa A.; Becker, Alan; Schindler, Jessica B.; Dion, Nancy; Oswalt, Jill
2010-01-01
Methamphetamine (meth) exposure during fetal development has the potential to adversely affect the development of multiple organ systems. An interdisciplinary case study of a 4-year 11-month-old child born to a mother addicted to meth revealed significant cognitive and communicative delays. Possible meth-related consequences for these delays…
Electronic Health Record Adoption as a Function of Success: Implications for Meaningful Use
ERIC Educational Resources Information Center
Naser, Riyad J.
2012-01-01
Successful electronic health records (EHR) implementation has the potential to transform the entire care delivery process across the enterprise. However, the rate of EHR implementation and use among physicians has been slow. Different factors have been reported in the literature that may hinder adoption of EHR. Identifying and managing these…
A Cognitive View of Reading Comprehension: Implications for Reading Difficulties
ERIC Educational Resources Information Center
Kendeou, Panayiota; Broek, Paul; Helder, Anne; Karlsson, Josefine
2014-01-01
Our aim in the present paper is to discuss a "cognitive view" of reading comprehension, with particular attention to research findings that have the potential to improve our understanding of difficulties in reading comprehension. We provide an overview of how specific sources of difficulties in inference making, executive functions, and…
USDA-ARS?s Scientific Manuscript database
The ubiquitin–proteasome pathway (UPP) plays important roles in many cellular functions, such as protein quality control, cell cycle control, and signal transduction. The selective degradation of aberrant proteins by the UPP is essential for the timely removal of potential cytotoxic damaged or other...
Population Abundance and Ecosystem Service Provision: The Case of Birds
Gaston, Kevin J; Cox, Daniel T C; Canavelli, Sonia B; García, Daniel; Hughes, Baz; Maas, Bea; Martínez, Daniel; Ogada, Darcy; Inger, Richard
2018-01-01
Abstract Although there is a diversity of concerns about recent persistent declines in the abundances of many species, the implications for the associated delivery of ecosystem services to people are surprisingly poorly understood. In principle, there are a broad range of potential functional relationships between the abundance of a species or group of species and the magnitude of ecosystem-service provision. Here, we identify the forms these relationships are most likely to take. Focusing on the case of birds, we review the empirical evidence for these functional relationships, with examples of supporting, regulating, and cultural services. Positive relationships between abundance and ecosystem-service provision are the norm (although seldom linear), we found no evidence for hump-shaped relationships, and negative ones were limited to cultural services that value rarity. Given the magnitude of abundance declines among many previously common species, it is likely that there have been substantial losses of ecosystem services, providing important implications for the identification of potential tipping points in relation to defaunation resilience, biodiversity conservation, and human well-being. PMID:29686433
Pathogenic Mechanisms and In Vitro Diagnosis of AERD
Schäfer, Dirk; Maune, Steffen
2012-01-01
Aspirin-exacerbated respiratory disease (AERD) refers to chronic rhinosinusitis, nasal polyposis, bronchoconstriction, and/or eosinophilic inflammation in asthmatics following the exposure to nonsteroidal anti-inflammatory drugs (NSAIDs). A key pathogenic mechanism associated with AERD is the imbalance of eicosanoid metabolism focusing on prostanoid and leukotriene pathways in airway mucosa as well as blood cells. Genetic and functional metabolic studies on vital and non-vital cells pointed to the variability and the crucial role of lipid mediators in disease susceptibility and their response to medication. Eicosanoids, exemplified by prostaglandin E2 (PGE2) and peptidoleukotrienes (pLT), are potential metabolic biomarkers contributing to the AERD phenotype. Also other mediators are implicated in the progress of AERD. Considering the various pathogenic mechanisms of AERD, a multitude of metabolic and genetic markers is suggested to be implicated and were introduced as potential biomarkers for in vitro diagnosis during the past decades. Deduced from an eicosanoid-related pathogenic mechanism, functional tests balancing PGE2 and pLT as well as other eicosanoids from preferentially vital leukocytes demonstrated their applicability for in vitro diagnosis of AERD. PMID:22654920
Alkaline Phosphatase, an Unconventional Immune Protein.
Rader, Bethany A
2017-01-01
Recent years have seen an increase in the number of studies focusing on alkaline phosphatases (APs), revealing an expanding complexity of function of these enzymes. Of the four human AP (hAP) proteins, most is known about tissue non-specific AP (TNAP) and intestinal AP (IAP). This review highlights current understanding of TNAP and IAP in relation to human health and disease. TNAP plays a role in multiple processes, including bone mineralization, vitamin B6 metabolism, and neurogenesis, is the genetic cause of hypophosphatasia, influences inflammation through regulation of purinergic signaling, and has been implicated in Alzheimer's disease. IAP regulates fatty acid absorption and has been implicated in the regulation of diet-induced obesity and metabolic syndrome. IAP and TNAP can dephosphorylate bacterial-derived lipopolysaccharide, and IAP has been identified as a potential regulator of the composition of the intestinal microbiome, an evolutionarily conserved function. Endogenous and recombinant bovine APs and recombinant hAPs are currently being explored for their potential as pharmacological agents to treat AP-associated diseases and mitigate multiple sources of inflammation. Continued research on these versatile proteins will undoubtedly provide insight into human pathophysiology, biochemistry, and the human holobiont.
Mesotrypsin promotes malignant growth of breast cancer cells through shedding of CD109
Hockla, Alexandra; Radisky, Derek C.
2010-01-01
Serine proteases have been implicated in many stages of cancer development, facilitating tumor cell growth, invasion, and metastasis, and naturally occurring serine protease inhibitors have shown promise as potential anticancer therapeutics. Optimal design of inhibitors as potential therapeutics requires the identification of the specific serine proteases involved in disease progression and the functional targets responsible for the tumor-promoting properties. Here, we use the HMT-3522 breast cancer progression series grown in 3D organotypic culture conditions to find that serine protease inhibitors cause morphological reversion of the malignant T4-2 cells, assessed by inhibition of proliferation and formation of acinar structures with polarization of basal markers, implicating serine protease activity in their malignant growth behavior. We identify PRSS3/mesotrypsin upregulation in T4-2 cells as compared to their nonmalignant progenitors, and show that knockdown of PRSS3 attenuates, and treatment with recombinant purified mesotrypsin enhances, the malignant growth phenotype. Using proteomic methods, we identify CD109 as the functional proteolytic target of mesotrypsin. Our study identifies a new mediator and effector of breast cancer growth and progression. PMID:20035377
Evidence for circulatory benefits of resveratrol in humans.
Wong, Rachel H X; Coates, Alison M; Buckley, Jonathan D; Howe, Peter R C
2013-07-01
Impairments of endothelial function, which can be assessed noninvasively by flow-mediated dilation (FMD) of the brachial artery, contribute to the development of cardiovascular disease. Associations between FMD and cognition suggest a vascular component in the loss of cognitive function. Certain vasoactive nutrients that have been shown to improve FMD may also have the potential to enhance cerebral perfusion and cognition. Preclinical studies show that trans-resveratrol can enhance nitric oxide bioavailability, thereby increasing endothelium-dependent vasodilation. We have now shown that acute administration of resveratrol elicits dose-dependent increases of FMD with greater potency than other vasoactive nutrients and that this benefit is sustained following regular consumption. We describe the potential implications of this vasodilator benefit of resveratrol and its role in enhancing cerebrovascular and cognitive functions. © 2013 New York Academy of Sciences.
Langberg, Joshua M.; Dvorsky, Melissa R.; Evans, Steven W.
2013-01-01
The purpose of the study was to evaluate the relation between ratings of Executive Function (EF) and academic functioning in a sample of 94 middle-school-aged youth with Attention-Deficit/Hyperactivity Disorder (ADHD; Mage = 11.9; 78% male; 21% minority). This study builds on prior work by evaluating associations between multiple specific aspects of EF (e.g., working memory, inhibition, and planning and organization) as rated by both parents and teachers on the Behavior Rating Inventory of Executive Function (BRIEF), with multiple academic outcomes, including school grades and homework problems. Further, this study examined the relationship between EF and academic outcomes above and beyond ADHD symptoms and controlled for a number of potentially important covariates, including intelligence and achievement scores. The EF Planning and Organization subscale as rated by both parents and teachers predicted school grades above and beyond symptoms of ADHD and relevant covariates. Parent ratings of youth’s ability to transition effectively between tasks/situations (Shift subscale) also predicted school grades. Parent-rated symptoms of inattention, hyperactivity/impulsivity, and planning and organization abilities were significant in the final model predicting homework problems. In contrast, only symptoms of inattention and the Organization of Materials subscale from the BRIEF were significant in the teacher model predicting homework problems. Organization and planning abilities are highly important aspects academic functioning for middle-school-aged youth with ADHD. Implications of these findings for the measurement of EF, and organization and planning abilities in particular, are discussed along with potential implications for intervention. PMID:23640285
Understanding the aetiology and resolution of chronic otitis media from animal and human studies
Thornton, Ruth B.; Kirkham, Lea-Ann S.; Kerschner, Joseph E.; Cheeseman, Michael T.
2017-01-01
ABSTRACT Inflammation of the middle ear, known clinically as chronic otitis media, presents in different forms, such as chronic otitis media with effusion (COME; glue ear) and chronic suppurative otitis media (CSOM). These are highly prevalent diseases, especially in childhood, and lead to significant morbidity worldwide. However, much remains unclear about this disease, including its aetiology, initiation and perpetuation, and the relative roles of mucosal and leukocyte biology, pathogens, and Eustachian tube function. Chronic otitis media is commonly modelled in mice but most existing models only partially mimic human disease and many are syndromic. Nevertheless, these models have provided insights into potential disease mechanisms, and have implicated altered immune signalling, mucociliary function and Eustachian tube function as potential predisposing mechanisms. Clinical studies of chronic otitis media have yet to implicate a particular molecular pathway or mechanism, and current human genetic studies are underpowered. We also do not fully understand how existing interventions, such as tympanic membrane repair, work, nor how chronic otitis media spontaneously resolves. This Clinical Puzzle article describes our current knowledge of chronic otitis media and the existing research models for this condition. It also identifies unanswered questions about its pathogenesis and treatment, with the goal of advancing our understanding of this disease to aid the development of novel therapeutic interventions. PMID:29125825
Early adversity and neural correlates of executive function: implications for academic adjustment.
McDermott, Jennifer M; Westerlund, Alissa; Zeanah, Charles H; Nelson, Charles A; Fox, Nathan A
2012-02-15
Early adversity can negatively impact the development of cognitive functions, although little is known about whether such effects can be remediated later in life. The current study examined one facet of executive functioning - inhibitory control - among children who experienced institutional care and explored the impact of a foster care intervention within the context of the Bucharest Early Intervention Project (BEIP). Specifically, a go/nogo task was administered when children were eight years old and behavioral and event-related potential (ERP) measures were collected. Results revealed that children assigned to care as usual (i.e. institutional care) were less accurate and exhibited slower neural responses compared to children assigned to the foster care intervention and children who had never been institutionalized. However, children in both the care as usual and foster care groups exhibited diminished attention processing of nogo cues as assessed via P300 amplitude. Foster care children also showed differential reactivity between correct and error responses via the error-related negativity (ERN) as compared to children in the care as usual group. Combined, the results highlight perturbations in neural sources of behavioral and attention problems among children experiencing early adversity. Potential implications for academic adjustment in at risk children are discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.
Christidi, Foteini; Migliaccio, Raffaella; Santamaría-García, Hernando; Santangelo, Gabriella; Trojsi, Francesca
2018-01-01
Social cognitive function, involved in the perception, processing, and interpretation of social information, has been shown to be crucial for successful communication and interpersonal relationships, thereby significantly impacting mental health, well-being, and quality of life. In this regard, assessment of social cognition, mainly focusing on four key domains, such as theory of mind (ToM), emotional empathy, and social perception and behavior, has been increasingly evaluated in clinical settings, given the potential implications of impairments of these skills for therapeutic decision-making. With regard to neurodegenerative diseases (NDs), most disorders, characterized by variable disease phenotypes and progression, although similar for the unfavorable prognosis, are associated to impairments of social cognitive function, with consequent negative effects on patients' management. Specifically, in some NDs these deficits may represent core diagnostic criteria, such as for behavioral variant frontotemporal dementia (bvFTD), or may emerge during the disease course as critical aspects, such as for Parkinson's and Alzheimer's diseases. On this background, we aimed to revise the most updated evidence on the neurobiological hypotheses derived from network-based approaches, clinical manifestations, and assessment tools of social cognitive dysfunctions in NDs, also prospecting potential benefits on patients' well-being, quality of life, and outcome derived from potential therapeutic perspectives of these deficits.
The potential for dams to impact lowland meandering river floodplain geomorphology.
Marren, Philip M; Grove, James R; Webb, J Angus; Stewardson, Michael J
2014-01-01
The majority of the world's floodplains are dammed. Although some implications of dams for riverine ecology and for river channel morphology are well understood, there is less research on the impacts of dams on floodplain geomorphology. We review studies from dammed and undammed rivers and include influences on vertical and lateral accretion, meander migration and cutoff formation, avulsion, and interactions with floodplain vegetation. The results are synthesized into a conceptual model of the effects of dams on the major geomorphic influences on floodplain development. This model is used to assess the likely consequences of eight dam and flow regulation scenarios for floodplain geomorphology. Sediment starvation downstream of dams has perhaps the greatest potential to impact on floodplain development. Such effects will persist further downstream where tributary sediment inputs are relatively low and there is minimal buffering by alluvial sediment stores. We can identify several ways in which floodplains might potentially be affected by dams, with varying degrees of confidence, including a distinction between passive impacts (floodplain disconnection) and active impacts (changes in geomorphological processes and functioning). These active processes are likely to have more serious implications for floodplain function and emphasize both the need for future research and the need for an "environmental sediment regime" to operate alongside environmental flows.
The Potential for Dams to Impact Lowland Meandering River Floodplain Geomorphology
Marren, Philip M.; Grove, James R.; Webb, J. Angus; Stewardson, Michael J.
2014-01-01
The majority of the world's floodplains are dammed. Although some implications of dams for riverine ecology and for river channel morphology are well understood, there is less research on the impacts of dams on floodplain geomorphology. We review studies from dammed and undammed rivers and include influences on vertical and lateral accretion, meander migration and cutoff formation, avulsion, and interactions with floodplain vegetation. The results are synthesized into a conceptual model of the effects of dams on the major geomorphic influences on floodplain development. This model is used to assess the likely consequences of eight dam and flow regulation scenarios for floodplain geomorphology. Sediment starvation downstream of dams has perhaps the greatest potential to impact on floodplain development. Such effects will persist further downstream where tributary sediment inputs are relatively low and there is minimal buffering by alluvial sediment stores. We can identify several ways in which floodplains might potentially be affected by dams, with varying degrees of confidence, including a distinction between passive impacts (floodplain disconnection) and active impacts (changes in geomorphological processes and functioning). These active processes are likely to have more serious implications for floodplain function and emphasize both the need for future research and the need for an “environmental sediment regime” to operate alongside environmental flows. PMID:24587718
Santamaría-García, Hernando; Santangelo, Gabriella
2018-01-01
Social cognitive function, involved in the perception, processing, and interpretation of social information, has been shown to be crucial for successful communication and interpersonal relationships, thereby significantly impacting mental health, well-being, and quality of life. In this regard, assessment of social cognition, mainly focusing on four key domains, such as theory of mind (ToM), emotional empathy, and social perception and behavior, has been increasingly evaluated in clinical settings, given the potential implications of impairments of these skills for therapeutic decision-making. With regard to neurodegenerative diseases (NDs), most disorders, characterized by variable disease phenotypes and progression, although similar for the unfavorable prognosis, are associated to impairments of social cognitive function, with consequent negative effects on patients' management. Specifically, in some NDs these deficits may represent core diagnostic criteria, such as for behavioral variant frontotemporal dementia (bvFTD), or may emerge during the disease course as critical aspects, such as for Parkinson's and Alzheimer's diseases. On this background, we aimed to revise the most updated evidence on the neurobiological hypotheses derived from network-based approaches, clinical manifestations, and assessment tools of social cognitive dysfunctions in NDs, also prospecting potential benefits on patients' well-being, quality of life, and outcome derived from potential therapeutic perspectives of these deficits. PMID:29854017
Use of a latency-based demand assessment to identify potential demands for functional analyses.
Call, Nathan A; Miller, Sarah J; Mintz, Joslyn Cynkus; Mevers, Joanna Lomas; Scheithauer, Mindy C; Eshelman, Julie E; Beavers, Gracie A
2016-12-01
Unlike potential tangible positive reinforcers, which are typically identified for inclusion in functional analyses empirically using preference assessments, demands are most often selected arbitrarily or based on caregiver report. The present study evaluated the use of a demand assessment with 12 participants who exhibited escape-maintained problem behavior. Participants were exposed to 10 demands, with aversiveness measured by average latency to the first instance of problem behavior. In subsequent functional analyses, results of a demand condition that included the demand with the shortest latency to problem behavior resulted in identification of an escape function for 11 of the participants. In contrast, a demand condition that included the demand with the longest latency resulted in identification of an escape function for only 5 participants. The implication of these findings is that for the remaining 7 participants, selection of the demand for the functional analysis without using the results of the demand assessment could have produced a false-negative finding. © 2016 Society for the Experimental Analysis of Behavior.
Integrins in bone metastasis formation and potential therapeutic implications.
Clëzardin, P
2009-11-01
Integrins constitute a family of cell surface receptors that are heterodimers composed of noncovalently associated alpha and beta subunits. Integrins bind to extracellular matrix proteins and immunogobulin superfamily molecules. They exert a stringent control on cell migration, survival and proliferation. However, their expression and functions are often deregulated in cancer, and many lines of evidence implicate them as key regulators during progression from primary tumor growth to metastasis. Here, we review the role of integrins in bone metastasis formation and present evidence that the use of integrin-targeted therapeutic agents may be an efficient strategy to block tumor metastasis.
Neurobiological correlates of social functioning in autism.
Neuhaus, Emily; Beauchaine, Theodore P; Bernier, Raphael
2010-08-01
Although autism is defined by deficits in three areas of functioning (social, communicative, and behavioral), impairments in social interest and restricted behavioral repertoires are central to the disorder. As a result, a detailed understanding of the neurobiological systems subserving social behavior may have implications for prevention, early identification, and intervention for affected families. In this paper, we review a number of potential neurobiological mechanisms--across several levels of analysis--that subserve normative social functioning. These include neural networks, neurotransmitters, and hormone systems. After describing the typical functioning of each system, we review available empirical findings specific to autism. Among the most promising potential mechanisms of social behavioral deficits in autism are those involving neural networks including the amygdala, the mesocorticolimbic dopamine system, and the oxytocin system. Particularly compelling are explanatory models that integrate mechanisms across biological systems, such as those linking dopamine and oxytocin with brain regions critical to reward processing. Copyright 2010 Elsevier Ltd. All rights reserved.
Biological soil crusts: Diminutive communities of potential global importance
Ferrenberg, Scott; Tucker, Colin; Reed, Sasha C.
2017-01-01
Biological soil crusts (biocrusts) are widespread, diverse communities of cyanobacteria, fungi, lichens, and mosses living on soil surfaces, primarily in drylands. Biocrusts can locally govern primary production, soil fertility, hydrology, and surface energy balance, with considerable variation in these functions across alternate community states. Further, these communities have been implicated in Earth system functioning via potential influences on global biogeochemistry and climate. Biocrusts are easily destroyed by disturbances and appear to be exceptionally vulnerable to warming temperatures and altered precipitation inputs, signaling possible losses of dryland functions with global change. Despite these concerns, we lack sufficient spatiotemporal data on biocrust function, cover, and community structure to confidently assess their ecological roles across the extensive dryland biome. Here, we present the case for cross-scale research and restoration efforts coupled with remote-sensing and modeling approaches that improve our collective understanding of biocrust responses to global change and the ecological roles of these diminutive communities at global scales.
Cellular Mechanisms of Somatic Stem Cell Aging
Jung, Yunjoon
2014-01-01
Tissue homeostasis and regenerative capacity rely on rare populations of somatic stem cells endowed with the potential to self-renew and differentiate. During aging, many tissues show a decline in regenerative potential coupled with a loss of stem cell function. Cells including somatic stem cells have evolved a series of checks and balances to sense and repair cellular damage to maximize tissue function. However, during aging the mechanisms that protect normal cell function begin to fail. In this review, we will discuss how common cellular mechanisms that maintain tissue fidelity and organismal lifespan impact somatic stem cell function. We will highlight context-dependent changes and commonalities that define aging, by focusing on three age-sensitive stem cell compartments: blood, neural, and muscle. Understanding the interaction between extrinsic regulators and intrinsic effectors that operate within different stem cell compartments is likely to have important implications for identifying strategies to improve health span and treat age-related degenerative diseases. PMID:24439814
Child, Nicholas D; Benarroch, Eduardo E
2014-03-18
Neurons contain different functional somatodendritic and axonal domains, each with a characteristic distribution of voltage-gated ion channels, synaptic inputs, and function. The dendritic tree of a cortical pyramidal neuron has 2 distinct domains, the basal and the apical dendrites, both containing dendritic spines; the different domains of the axon are the axonal initial segment (AIS), axon proper (which in myelinated axons includes the node of Ranvier, paranodes, juxtaparanodes, and internodes), and the axon terminals. In the cerebral cortex, the dendritic spines of the pyramidal neurons receive most of the excitatory synapses; distinct populations of γ-aminobutyric acid (GABA)ergic interneurons target specific cellular domains and thus exert different influences on pyramidal neurons. The multiple synaptic inputs reaching the somatodendritic region and generating excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) sum and elicit changes in membrane potential at the AIS, the site of initiation of the action potential.
Rodriguez, Christina M
2006-04-01
To explore cognitive and emotional factors that may exacerbate child-abuse potential among domestic violence victims, 80 participants reported on their depression, hopelessness, anxiety, and anger as well as their attachment style and attributional style. Increased emotional difficulties as well as insecure attachment styles were significantly positively correlated with child abuse potential, although depression and anxiety were the strongest predictors. Externalizing blame for the spousal abuse was not associated with abuse risk. Women residing in shelters demonstrated significantly greater abuse risk than those in transitional housing programs, suggesting that greater temporal proximity to the spousal abuse may in part account for the increased abuse potential. Depression and hopelessness, however, appeared particularly relevant to increased abuse risk in domestic violence victims in the transitional housing system. Implications of these findings for working with battered women in terms of their emotional functioning and attachment style are discussed.
MicroRNA-542-5p as a Novel Tumor Suppressor in Neuroblastoma
Bray, Isabella; Tivnan, Amanda; Bryan, Kenneth; Foley, Niamh H; Watters, Karen M; Tracey, Lorraine; Davidoff, Andrew M; Stallings, Raymond L
2011-01-01
Several studies have implicated the dysregulation of microRNAs in neuroblastoma pathogenesis, an often fatal paediatric cancer arising from precursor cells of the sympathetic nervous system. Our group and others have demonstrated that lower expression of miR-542-5p is highly associated with poor patient survival, indicating a potential tumor suppressive function. Here, we demonstrate that ectopic over-expression of this miRNA decreases the invasive potential of neuroblastoma cell lines in vitro, along with primary tumor growth and metastases in an orthotopic mouse xenograft model, providing the first functional evidence for the involvement of miR-542-5p as a tumor suppressor in any type of cancer. PMID:21310526
Goshima, Yoshio; Hida, Tomonobu; Gotoh, Toshiyuki
2012-01-01
Axonal transport plays a crucial role in neuronal morphogenesis, survival and function. Despite its importance, however, the molecular mechanisms of axonal transport remain mostly unknown because a simple and quantitative assay system for monitoring this cellular process has been lacking. In order to better characterize the mechanisms involved in axonal transport, we formulate a novel computer-assisted monitoring system of axonal transport. Potential uses of this system and implications for future studies will be discussed.
Escaño, Mary Clare Sison; Arevalo, Ryan Lacdao; Gyenge, Elod; Kasai, Hideaki
2014-09-03
The electrocatalysis of borohydride oxidation is a complex, up-to-eight-electron transfer process, which is essential for development of efficient direct borohydride fuel cells. Here we review the progress achieved by density functional theory (DFT) calculations in explaining the adsorption of BH4(-) on various catalyst surfaces, with implications for electrocatalyst screening and selection. Wherever possible, we correlate the theoretical predictions with experimental findings, in order to validate the proposed models and to identify potential directions for further advancements.
NASA Astrophysics Data System (ADS)
Sison Escaño, Mary Clare; Lacdao Arevalo, Ryan; Gyenge, Elod; Kasai, Hideaki
2014-09-01
The electrocatalysis of borohydride oxidation is a complex, up-to-eight-electron transfer process, which is essential for development of efficient direct borohydride fuel cells. Here we review the progress achieved by density functional theory (DFT) calculations in explaining the adsorption of BH4- on various catalyst surfaces, with implications for electrocatalyst screening and selection. Wherever possible, we correlate the theoretical predictions with experimental findings, in order to validate the proposed models and to identify potential directions for further advancements.
Bilić, Ante; Reimers, Jeffrey R; Hush, Noel S
2005-03-01
The adsorption of phenylthiol on the Au(111) surface is modeled using Perdew and Wang density-functional calculations. Both direct molecular physisorption and dissociative chemisorption via S-H bond cleavage are considered as well as dimerization to form disulfides. For the major observed product, the chemisorbed thiol, an extensive potential-energy surface is produced as a function of both the azimuthal orientation of the adsorbate and the linear translation of the adsorbate through the key fcc, hcp, bridge, and top binding sites. Key structures are characterized, the lowest-energy one being a broad minimum of tilted orientation ranging from the bridge structure halfway towards the fcc one. The vertically oriented threefold binding sites, often assumed to dominate molecular electronics measurements, are identified as transition states at low coverage but become favored in dense monolayers. A similar surface is also produced for chemisorption of phenylthiol on Ag(111); this displays significant qualitative differences, consistent with the qualitatively different observed structures for thiol chemisorption on Ag and Au. Full contours of the minimum potential energy as a function of sulfur translation over the crystal face are described, from which the barrier to diffusion is deduced to be 5.8 kcal mol(-1), indicating that the potential-energy surface has low corrugation. The calculated bond lengths, adsorbate charge and spin density, and the density of electronic states all indicate that, at all sulfur locations, the adsorbate can be regarded as a thiyl species that forms a net single covalent bond to the surface of strength 31 kcal mol(-1). No detectable thiolate character is predicted, however, contrary to experimental results for alkyl thiols that indicate up to 20%-30% thiolate involvement. This effect is attributed to the asymptotic-potential error of all modern density functionals that becomes manifest through a 3-4 eV error in the lineup of the adsorbate and substrate bands. Significant implications are described for density-functional calculations of through-molecule electron transport in molecular electronics.
Association of MC4R variants with obesity-related traits in Hispanic children
USDA-ARS?s Scientific Manuscript database
Melanocortin 4 receptor (MC4R) has been implicated in the regulation of appetite and energy expenditure. In children, MC4R mutations have been associated with severe obesity. The main objective of this study was to investigate the potential functional effects of variants in MC4R gene on the variatio...
The South's outlook for sustainable forest bioenergy and biofuels production
David Wear; Robert Abt; Janaki Alavalapati; Greg Comatas; Mike Countess; Will McDow
2010-01-01
The future of a wood-based biofuel/bioenergy sector could hold important implications for the use, structure and function of forested landscapes in the South. This paper examines a set of questions regarding the potential effects of biofuel developments both on markets for traditional timber products and on the provision of various non-timber ecosystem services. In...
USDA-ARS?s Scientific Manuscript database
Benghal dayflower (BD) is an exotic weed that reduces yields in many agricultural crops. Potential dispersal of this weed by migratory Mourning doves was investigated in this study. Evidence shows that doves feed on BD seeds, with some birds containing hundreds of seeds. Seeds extracted from harvest...
ERIC Educational Resources Information Center
Lucey, Christopher F.; Lam, Sarah K. Y.
2012-01-01
This study was designed to identify characteristics of family functioning that relate to suicide potential in an outpatient adolescent population. Participants included 51 adolescents between the ages of 14 and 18 who were involved in outpatient counselling. The Family Environment Scale and the Suicide Probability Scale were used to assess…
Soil organic nitrogen mineralization across a global latitudinal gradient
D.L. Jones; K. Kielland; F.L. Sinclair; R.A. Dahlgren; K.K. Newsham; J.F. Farrar; D.V. Murphy
2009-01-01
Understanding and accurately predicting the fate of carbon and nitrogen in the terrestrial biosphere remains a central goal in ecosystem science. Amino acids represent a key pool of C and N in soil, and their availability to plants and microorganisms has been implicated as a major driver in regulating ecosystem functioning. Because of potential differences in...
ERIC Educational Resources Information Center
Brown, Ann L.; French, Lucia A.
The practice and interpretation of intelligence testing of educable retarded and learning disabled children is examined in this report. The current and future state of intelligence testing is discussed in terms of its predictive, diagnostic, and remedial functions. The first section places a consideration of individual testing formats within a…
The Elderly Population with Chronic Functional Disability: Implications for Home Care Eligibility.
ERIC Educational Resources Information Center
Stone, Robyn I.; Murtaugh, Christopher M.
1990-01-01
Assessed effect of changes in minimum number of activities of daily living (ALD) and instrumental activities of daily living (IADL) limitations, types of help, and duration of disability required on size of population potentially eligible for home care benefits. Only 411,000 elders met restrictive disability criteria; over 4 million would qualify…
KCNT1 gain-of-function in two epilepsy phenotypes is reversed by quinidine
Milligan, Carol J.; Li, Melody; Gazina, Elena V.; Heron, Sarah E.; Nair, Umesh; Trager, Chantel; Reid, Christopher A.; Venkat, Anu; Younkin, Donald P.; Dlugos, Dennis J.; Petrovski, Slavé; Goldstein, David B.; Dibbens, Leanne M.; Scheffer, Ingrid E.; Berkovic, Samuel F; Petrou, Steven
2014-01-01
Objective Mutations in KCNT1 have been implicated in autosomal dominant nocturnal frontal lobe epilepsy (ADNFLE) and epilepsy of infancy with migrating focal seizures (EIMFS). More recently, a whole exome sequencing study of epileptic encephalopathies identified an additional de novo mutation in one proband with EIMFS. We aim to investigate the electrophysiological and pharmacological characteristics of hKCNT1 mutations and examine developmental expression levels. Methods Here we use a Xenopus laevis oocyte based automated two-electrode voltage-clamp assay. The effects of quinidine (100 and 300 µM) are also tested. Using quantitative RT-PCR, the relative levels of mouse brain mKcnt1 mRNA expression are determined. Results We demonstrate that KCNT1 mutations implicated in epilepsy cause a marked increase in function. Importantly, there was a significant group difference in gain-of-function between mutations associated with ADNFLE and EIMFS. Finally, exposure to quinidine significantly reduces this gain-of-function for all mutations studied. Interpretation These results establish direction for a targeted therapy and potentially exemplify a translational paradigm for in vitro studies informing novel therapies in a neuropsychiatric disease. PMID:24591078
The human sirtuin family: Evolutionary divergences and functions
2011-01-01
The sirtuin family of proteins is categorised as class III histone deacetylases that play complex and important roles in ageing-related pathological conditions such as cancer and the deregulation of metabolism. There are seven members in humans, divided into four classes, and evolutionarily conserved orthologues can be found in most forms of life, including both eukaryotes and prokaryotes. The highly conserved catalytic core domain composed of a large oxidised nicotinamide adenine dinucleotide (NAD+)-binding Rossmann fold subunit suggests that these proteins belong to a family of nutrient-sensing regulators. Along with their function in regulating cellular metabolism in response to stressful conditions, they are implicated in modifying a wide variety of substrates; this increases the complexity of unravelling the interplay of sirtuins and their partners. Over the past few years, all of these new findings have attracted the interest of researchers exploring potential therapeutic implications related to the function of sirtuins. It remains to be elucidated whether, indeed, sirtuins can serve as molecular targets for the treatment of human illnesses. PMID:21807603
Kura, Branislav; Babal, Pavel; Slezak, Jan
2017-10-01
Radiotherapy is the most commonly used methodology to treat oncological disease, one of the most widespread causes of death worldwide. Oncological patients cured by radiotherapy applied to the mediastinal area have been shown to suffer from cardiovascular disease. The increase in the prevalence of radiation-induced heart disease has emphasized the need to seek new therapeutic targets to mitigate the negative impact of radiation on the heart. In this regard, microRNAs (miRNAs) have received considerable interest. miRNAs regulate post-transcriptional gene expression by their ability to target various mRNA sequences because of their imperfect pairing with mRNAs. It has been recognized that miRNAs modulate a diverse spectrum of cardiac functions with developmental, pathophysiological, and clinical implications. This makes them promising potential targets for diagnosis and treatment. This review summarizes the recent findings about the possible involvement of miRNAs in radiation-induced heart disease and their potential use as diagnostic or treatment targets in this respect.
Drug-Gut Microbiota Interactions: Implications for Neuropharmacology.
Walsh, Jacinta; Griffin, Brendan T; Clarke, Gerard; Hyland, Niall P
2018-05-21
The fate and activity of drugs are frequently dictated not only by the host per se but also by the microorganisms present in the gastrointestinal tract. The gut microbiome is known to, both directly and indirectly, affect drug metabolism. More evidence now hints at the impact that drugs can have on the function and composition of the gut microbiome. Both microbiota-mediated alterations in drug metabolism and drug-mediated alterations in the gut microbiome can have beneficial or detrimental effects on the host. Greater insights into the mechanisms driving these reciprocal drug-gut microbiota interactions are needed, to guide the development of microbiome-targeted dietary or pharmacological interventions, with the potential to enhance drug efficacy or reduce drug side-effects. In this review, we explore the relationship between drugs and the gut microbiome, with a specific focus on potential mechanisms underpinning the drug-mediated alterations on the gut microbiome and the potential implications for psychoactive drugs. This article is protected by copyright. All rights reserved.
Disease implication of hyper-Hippo signalling.
Wang, Shu-Ping; Wang, Lan-Hsin
2016-10-01
The Hippo signalling pathway regulates cellular proliferation, apoptosis and differentiation, thus exerting profound effects on cellular homeostasis. Inhibition of Hippo signalling has been frequently implicated in human cancers, indicating a well-known tumour suppressor function of the Hippo pathway. However, it is less certain whether and how hyperactivation of the Hippo pathway affects biological outcome in living cells. This review describes current knowledge of the regulatory mechanisms of the Hippo pathway, mainly focusing on hyperactivation of the Hippo signalling nexus. The disease implications of hyperactivated Hippo signalling have also been discussed, including arrhythmogenic cardiomyopathy, Sveinsson's chorioretinal atrophy, Alzheimer's disease, amyotrophic lateral sclerosis and diabetes. By highlighting the significance of disease-relevant Hippo signalling activation, this review can offer exciting prospects to address the onset and potential reversal of Hippo-related disorders. © 2016 The Authors.
Disease implication of hyper-Hippo signalling
Wang, Shu-Ping
2016-01-01
The Hippo signalling pathway regulates cellular proliferation, apoptosis and differentiation, thus exerting profound effects on cellular homeostasis. Inhibition of Hippo signalling has been frequently implicated in human cancers, indicating a well-known tumour suppressor function of the Hippo pathway. However, it is less certain whether and how hyperactivation of the Hippo pathway affects biological outcome in living cells. This review describes current knowledge of the regulatory mechanisms of the Hippo pathway, mainly focusing on hyperactivation of the Hippo signalling nexus. The disease implications of hyperactivated Hippo signalling have also been discussed, including arrhythmogenic cardiomyopathy, Sveinsson's chorioretinal atrophy, Alzheimer's disease, amyotrophic lateral sclerosis and diabetes. By highlighting the significance of disease-relevant Hippo signalling activation, this review can offer exciting prospects to address the onset and potential reversal of Hippo-related disorders. PMID:27805903
Lind, Christopher; Meyer, Carly; Young, Jessica
2016-01-01
The International Classification of Functioning, Disability and Health (ICF) has been applied widely in the literature to describe and differentiate the broad implications of hearing impairment (HI) and cognitive impairment (CI) on communication. As CI and HI are largely age-related conditions, the likelihood of comorbidity of these conditions is high. In the context of an aging population, the prevalence of comorbidity is likely to rise, yet much of the clinical assessment and intervention in HI and CI occur separately. The benefit of addressing the dual impact of these conditions is of increasing clinical importance for all clinicians working with older adults and for audiologists and speech pathologists in particular. In this article, the ICF model will be applied to explore the everyday implications of HI and CI. Furthermore, the clinical implications of the ICF model are explored with particular respect to communication assessment and intervention options. The potential benefit of combining activity- and participation-focused interventions currently offered for HI and CI independently is examined. PMID:27489399
Qualitative breakdown of the unrestricted Hartree-Fock energy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mori-Sánchez, Paula, E-mail: paula.mori@uam.es; Cohen, Aron J., E-mail: ajc54@cam.ac.uk
2014-10-28
The stretching of closed-shell molecules is a qualitative problem for restricted Hartree-Fock that is usually circumvented by the use of unrestricted Hartree-Fock (UHF). UHF is well known to break the spin symmetry at the Coulson-Fischer point, leading to a discontinuous derivative in the potential energy surface and incorrect spin density. However, this is generally not considered as a major drawback. In this work, we present a set of two electron molecules which magnify the problem of symmetry breaking and lead to drastically incorrect potential energy surfaces with UHF. These molecules also fail with unrestricted density-functional calculations where a functional suchmore » as B3LYP gives both symmetry breaking and an unphysically low energy due to the delocalization error. The implications for density functional theory are also discussed.« less
Analysis of the pattern of potential woody cover in Texas savanna
NASA Astrophysics Data System (ADS)
Yang, Xuebin; Crews, Kelley A.; Yan, Bowei
2016-10-01
While woody plant encroachment has been observed worldwide in savannas and adversely affected the ecosystem structure and function, a thorough understanding of the nature of this phenomenon is urgently required for savanna management and restoration. Among others, potential woody cover (the maximum realizable woody cover that a given site can support), especially its variation over environment has huge implication on the encroachment management in particular, and on tree-grass interactions in general. This project was designed to explore the pattern of potential woody cover in Texas savanna, an ecosystem with a large rainfall gradient in west-east direction. Substantial random pixels were sampled across the study area from MODIS Vegetation Continuous Fields (VCF) tree cover layer (250 m). Since potential woody cover is suggested to be limited by water availability, a nonlinear 99th quantile regression was performed between the observed woody cover and mean annual precipitation (MAP) to model the pattern of potential woody cover. Research result suggests a segmented relationship between potential woody cover and MAP at MODIS scale. Potential biases as well as the practical and theoretical implications were discussed. Through this study, the hypothesis about the primary role of water availability in determining savanna woody cover was further confirmed in a relatively understudied US-located savanna.
Wiley, N C; Dinan, T G; Ross, R P; Stanton, C; Clarke, G; Cryan, J F
2017-07-01
The brain-gut-microbiota axis comprises an extensive communication network between the brain, the gut, and the microbiota residing there. Development of a diverse gut microbiota is vital for multiple features of behavior and physiology, as well as many fundamental aspects of brain structure and function. Appropriate early-life assembly of the gut microbiota is also believed to play a role in subsequent emotional and cognitive development. If the composition, diversity, or assembly of the gut microbiota is impaired, this impairment can have a negative impact on host health and lead to disorders such as obesity, diabetes, inflammatory diseases, and even potentially neuropsychiatric illnesses, including anxiety and depression. Therefore, much research effort in recent years has focused on understanding the potential of targeting the intestinal microbiota to prevent and treat such disorders. This review aims to explore the influence of the gut microbiota on host neural function and behavior, particularly those of relevance to stress-related disorders. The involvement of microbiota in diverse neural functions such as myelination, microglia function, neuronal morphology, and blood-brain barrier integrity across the life span, from early life to adolescence to old age, will also be discussed. Nurturing an optimal gut microbiome may also prove beneficial in animal science as a means to manage stressful situations and to increase productivity of farm animals. The implications of these observations are manifold, and researchers are hopeful that this promising body of preclinical work can be successfully translated to the clinic and beyond.
Estrogen-Cholinergic Interactions: Implications for Cognitive Aging
Newhouse, Paul; Dumas, Julie
2015-01-01
While many studies in humans have investigated the effects of estrogen and hormone therapy on cognition, potential neurobiological correlates of these effects have been less well studied. An important site of action for estrogen in the brain is the cholinergic system. Several decades of research support the critical role of CNS cholinergic systems in cognition in humans, particularly in learning and memory formation and attention. In humans, the cholinergic system has been implicated in many aspects of cognition including the partitioning of attentional resources, working memory, inhibition of irrelevant information, and improved performance on effort-demanding tasks. Studies support the hypothesis that estradiol helps to maintain aspects of attention and verbal and visual memory. Such cognitive domains are exactly those modulated by cholinergic systems and extensive basic and preclinical work over the past several decades has clearly shown that basal forebrain cholinergic systems are dependent on estradiol support for adequate functioning. This paper will review recent human studies from our laboratories and others that have extended preclinical research examining estrogen-cholinergic interactions to humans. Studies examined include estradiol and cholinergic antagonist reversal studies in normal older women, examinations of the neural representations of estrogen-cholinergic interactions using functional brain imaging, and studies of the ability of selective estrogen receptor modulators such as tamoxifen to interact with cholinergic-mediated cognitive performance. We also discuss the implications of these studies for the underlying hypotheses of cholinergic-estrogen interactions and cognitive aging, and indications for prophylactic and therapeutic potential that may exploit these effects. PMID:26187712
Selfors, Laura M.; Schutzman, Jennifer L.; Borland, Christina Z.; Stern, Michael J.
1998-01-01
Activation of fibroblast growth factor (FGF) receptors elicits diverse cellular responses including growth, mitogenesis, migration, and differentiation. The intracellular signaling pathways that mediate these important processes are not well understood. In Caenorhabditis elegans, suppressors of clr-1 identify genes, termed soc genes, that potentially mediate or activate signaling through the EGL-15 FGF receptor. We demonstrate that three soc genes, soc-1, soc-2, and sem-5, suppress the activity of an activated form of the EGL-15 FGF receptor, consistent with the soc genes functioning downstream of EGL-15. We show that soc-2 encodes a protein composed almost entirely of leucine-rich repeats, a domain implicated in protein–protein interactions. We identified a putative human homolog, SHOC-2, which is 54% identical to SOC-2. We find that shoc-2 maps to 10q25, shoc-2 mRNA is expressed in all tissues assayed, and SHOC-2 protein is cytoplasmically localized. Within the leucine-rich repeats of both SOC-2 and SHOC-2 are two YXNX motifs that are potential tyrosine-phosphorylated docking sites for the SEM-5/GRB2 Src homology 2 domain. However, phosphorylation of these residues is not required for SOC-2 function in vivo, and SHOC-2 is not observed to be tyrosine phosphorylated in response to FGF stimulation. We conclude that this genetic system has allowed for the identification of a conserved gene implicated in mediating FGF receptor signaling in C. elegans. PMID:9618511
Macieira-Coelho, A
1995-01-01
Many gerontologists have been misdirected by the conclusion that the decline in the division potential of some cell compartments during aging is due to the increase in nondividing cells. Terminal postmitotic cells are called senescent cells although there is no evidence that they have any implications for aging of the organism. In an experimental system, Hayflick found a drift in cell functions created by proliferation, which is of relevance to the aging of the organism. Experimental evidence suggests that the presence of terminal postmitotic cells in excess in the tissues is associated with aging-related pathological states.
Reduced Gas Cycling in Microbial Mats: Implications for Early Earth
NASA Technical Reports Server (NTRS)
Hoehler, Tori M.; Bebout, Brad M.; DesMarais, David J.; DeVincenzi, Donald L. (Technical Monitor)
2000-01-01
For more than half the history of life on Earth, biological productivity was dominated by photosynthetic microbial mats. During this time, mats served as the preeminent biological influence on earth's surface and atmospheric chemistry and also as the primary crucible for microbial evolution. We find that modern analogs of these ancient mat communities generate substantial quantities of hydrogen, carbon monoxide, and methane. Escape of these gases from the biosphere would contribute strongly to atmospheric evolution and potentially to the net oxidation of earth's surface; sequestration within the biosphere carries equally important implications for the structure, function, and evolution of anaerobic microbial communities within the context of mat biology.
Uses of the Cell Phone for Education in the Philippines and Mongolia
ERIC Educational Resources Information Center
Librero, Felix; Ramos, Angelo Juan; Ranga, Adelina I.; Trinona, Jerome; Lambert, David
2007-01-01
The cell phone, now the most widely used medium in Asia, has major educational implications. Most users, however, do not realize the cell phone's potential for education, nor even for the communication functions for which it was originally designed. Most educators still see the computer and the cell phone as unrelated devices, and the tiny cell…
Aerophagia and belching after herpes simplex encephalitis.
Scheid, Rainer; Teich, Niels; Schroeter, Matthias L
2008-03-01
The etiology of abnormal belching is not known. Currently, it is being subsumed under "functional gastroduodenal disorders." Here, we report the unusual case history of a patient who developed aerophagia and consecutive excessive belching in association with herpes simplex encephalitis. The case report adds to the limited information about potential organic geneses of belching. Implications for possible medical therapies are discussed.
Crystal L. Raymond; Donald McKenzie
2014-01-01
We quantified carbon (C) dynamics of forests in Washington, US using theoretical models of C dynamics as a function of forest age. We fit empirical models to chronosequences of forest inventory data at two scales: a coarse-scale ecosystem classification (ecosections) and forest types (potential vegetation) within ecosections. We hypothesized that analysis at the finer...
ERIC Educational Resources Information Center
Johnson, Eugene G.; Lazer, Stephen; O'Sullivan, Christine Y.
Chapters in this report outline the potential plans for the redesign of the National Assessment of Educational Progress (NAEP). It is argued that any successful redesign must consider the NAEP as a whole. This report reviews overall NAEP designs and discusses the implications that each of the designs has for various functional areas. The following…
Soil health paradigms and implications for disease management.
Larkin, Robert P
2015-01-01
Soil health has been defined as the capacity of soil to function as a vital living system to sustain biological productivity, maintain environmental quality, and promote plant, animal, and human health. Building and maintaining soil health are essential to agricultural sustainability and ecosystem function. Management practices that promote soil health, including the use of crop rotations, cover crops and green manures, organic amendments, and conservation tillage, also have generally positive effects on the management of soilborne diseases through a number of potential mechanisms, including increasing soil microbial biomass, activity, and diversity, resulting in greater biological suppression of pathogens and diseases. However, there also may be particular disease issues associated with some soil health management practices. In this review, research and progress made over the past twenty years regarding soil health, sustainability, and soil health management practices, with an emphasis on their implications for and effects on plant disease and disease management strategies, are summarized.
Wu, Haipeng; Lai, Cui; Zeng, Guangming; Liang, Jie; Chen, Jin; Xu, Jijun; Dai, Juan; Li, Xiaodong; Liu, Junfeng; Chen, Ming; Lu, Lunhui; Hu, Liang; Wan, Jia
2017-09-01
Compost and biochar, used for the remediation of soil, are seen as attractive waste management options for the increasing volume of organic wastes being produced. This paper reviews the interaction of biochar and composting and its implication for soil amendment and pollution remediation. The interaction of biochar and composting affect each other's properties. Biochar could change the physico-chemical properties, microorganisms, degradation, humification and gas emission of composting, such as the increase of nutrients, cation exchange capacity (CEC), organic matter and microbial activities. The composting could also change the physico-chemical properties and facial functional groups of biochar, such as the improvement of nutrients, CEC, functional groups and organic matter. These changes would potentially improve the efficiency of the biochar and composting for soil amendment and pollution remediation. Based on the above review, this paper also discusses the future research required in this field.
Roles and Functions of Community Health Workers in Primary Care.
Hartzler, Andrea L; Tuzzio, Leah; Hsu, Clarissa; Wagner, Edward H
2018-05-01
Community health workers have potential to enhance primary care access and quality, but remain underutilized. To provide guidance on their integration, we characterized roles and functions of community health workers in primary care through a literature review and synthesis. Analysis of 30 studies identified 12 functions (ie, care coordination, health coaching, social support, health assessment, resource linking, case management, medication management, remote care, follow-up, administration, health education, and literacy support) and 3 prominent roles representing clusters of functions: clinical services, community resource connections, and health education and coaching. We discuss implications for community health worker training and clinical support in primary care. © 2018 Annals of Family Medicine, Inc.
Mapping Variation in Vegetation Functioning with Imaging Spectroscopy
NASA Astrophysics Data System (ADS)
Townsend, P. A.; Couture, J. J.; Kruger, E. L.; Serbin, S.; Singh, A.
2015-12-01
Imaging spectroscopy (otherwise known as hyperspectral remote sensing) offers the potential to characterize the spatial and temporal variation in biophysical and biochemical properties of vegetation that can be costly or logistically difficult to measure comprehensively using traditional methods. A number of recent studies have illustrated the capacity for imaging spectroscopy data, such as from NASA's AVIRIS sensor, to empirically estimate functional traits related to foliar chemistry and physiology (Singh et al. 2015, Serbin et al. 2015). Here, we present analyses that illustrate the implications of those studies to characterize within-field or -stand variability in ecosystem functioning. In agricultural ecosystems, within-field photosynthetic capacity can vary by 30-50%, likely due to within-field variations in water availability and soil fertility. In general, the variability of foliar traits is lower in forests than agriculture, but can still be significant. Finally, we demonstrate that functional trait variability at the stand scale is strongly related to vegetation diversity. These results have two significant implications: 1) reliance on a small number of field samples to broadly estimate functional traits likely underestimates variability in those traits, and 2) if trait estimations from imaging spectroscopy are reliable, such data offer the opportunity to greatly increase the density of measurements we can use to predict ecosystem function.
Valentino, Kristin; Hibel, Leah C; Cummings, E. Mark; Nuttall, Amy K.; Comas, Michelle; McDonnell, Christina G.
2016-01-01
Theoretical and empirical evidence suggest that the way in which parents discuss everyday emotional experiences with their young children (i.e., elaborative reminiscing) has significant implications for child cognitive and socio-emotional functioning, and that maltreating parents have a particularly difficult time in engaging in this type of dialogue. This dyadic interactional exchange, therefore, has the potential to be an important process variable linking child maltreatment to developmental outcomes at multiple levels of analysis. The current investigation evaluated the role of maternal elaborative reminiscing in associations between maltreatment and child cognitive, emotional, and physiological functioning. Participants included 43 maltreated and 49 nonmaltreated children (aged 3–6) and their mothers. Dyads participated in a joint reminiscing task about four past emotional events, and children participated in assessments of receptive language and emotion knowledge. Child salivary cortisol was also collected from children three times a day (waking, midday, and bedtime) on two consecutive days to assess daily levels and diurnal decline. Results indicated that maltreating mothers engaged in significantly less elaborative reminiscing than nonmaltreating mothers. Maternal elaborative reminiscing mediated associations between child maltreatment and child receptive language and child emotion knowledge. Additionally, there was support for an indirect pathway between child maltreatment and child cortisol diurnal decline through maternal elaborative reminiscing. Directions for future research are discussed and potential clinical implications are addressed. PMID:26535941
Bot, Nathalie; Schweizer, Claude; Ben Halima, Saoussen; Fraering, Patrick C.
2011-01-01
Neurexins (NRXNs) are synaptic cell adhesion molecules having essential roles in the assembly and maturation of synapses into fully functional units. Immunocytochemical and electrophysiological studies have shown that specific binding across the synaptic cleft of the ectodomains of presynaptic NRXNs and postsynaptic neuroligins have the potential to bidirectionally coordinate and trigger synapse formation. Moreover, in vivo studies as well as genome-wide association studies pointed out implication of NRXNs in the pathogenesis of cognitive disorders including autism spectrum disorders and different types of addictions including opioid and alcohol dependences, suggesting an important role in synaptic function. Despite extensive investigations, the mechanisms by which NRXNs modulate the properties of synapses remain largely unknown. We report here that α- and γ-secretases can sequentially process NRXN3β, leading to the formation of two final products, an ∼80-kDa N-terminal extracellular domain of Neurexin-3β (sNRXN3β) and an ∼12-kDa C-terminal intracellular NRXN3β domain (NRXN3β-ICD), both of them being potentially implicated in the regulation of NRXNs and neuroligins functions at the synapses or in yet unidentified signal transduction pathways. We further report that this processing is altered by several PS1 mutations in the catalytic subunit of the γ-secretase that cause early-onset familial Alzheimer disease. PMID:21084300
Shi, Yu; Liu, Rui; Zhang, Si; Xia, Yin-Yan; Yang, Hai-Jie; Guo, Ke; Zeng, Qi; Feng, Zhi-Wei
2011-04-01
Neural cell adhesion molecule (NCAM) has been implicated in tumor metastasis yet its function in melanoma progression remains unclear. Here, we demonstrate that stably silencing NCAM expression in mouse melanoma B16F0 cells perturbs their cellular invasion and metastatic dissemination in vivo. The pro-invasive function of NCAM is exerted via dual mechanisms involving both cAMP-dependent protein kinase (PKA) and phosphatidylinositol 3-kinase (PI3K) pathways. Pharmacologic inhibition of PKA and PI3K leads to impaired cellular invasion. In contrast, forced expression of constitutively activated Akt, the major downstream target of PI3K, restores the defective cellular invasiveness of NCAM knock-down (KD) B16F0 cells. Furthermore, attenuation of either PKA or Akt activity in NCAM KD cells is shown to affect their common downstream target, transcription factor cAMP response element binding protein (CREB), which in turn down-regulates mRNA expression of matrix metalloproteinase-2 (MMP-2), thus contributes to impaired cellular invasion and metastasis of melanoma cells. Together, these findings indicate that NCAM potentiates cellular invasion and metastasis of melanoma cells through stimulation of PKA and PI3K signaling pathways thus suggesting the potential implication of anti-NCAM strategy in melanoma treatment. Copyright © 2011 Elsevier Ltd. All rights reserved.
Printing Insecurity? The Security Implications of 3D-Printing of Weapons.
Walther, Gerald
2015-12-01
In 2013, the first gun printed out of plastic by a 3D-printer was successfully fired in the U.S. This event caused a major media hype about the dangers of being able to print a gun. Law enforcement agencies worldwide were concerned about this development and the potentially huge security implications of these functional plastic guns. As a result, politicians called for a ban of these weapons and a control of 3D-printing technology. This paper reviews the security implications of 3D-printing technology and 3D guns. It argues that current arms control and transfer policies are adequate to cover 3D-printed guns as well. However, while this analysis may hold up currently, progress in printing technology needs to be monitored to deal with future dangers pre-emptively.
Peripheral inflammation and cognitive aging.
Lim, Alvin; Krajina, Katarina; Marsland, Anna L
2013-01-01
Evidence suggests that inflammation, an innate immune response facilitating recovery from injury and pathogenic invasion, is positively associated with age-related cognitive decline and may play a role in risk for dementia. Physiological pathways linking the peripheral immune and central nervous systems are outlined, and studies linking inflammation with neurocognitive function are overviewed. We also present recent studies from our laboratory showing that midlife inflammation is related to cognitive function and brain morphology. Finally, potential implications for treatment, future directions, and limitations are discussed. Copyright © 2013 S. Karger AG, Basel.
Functional response of wolves preying on barren-ground caribou in a multiple-prey ecosystem
Dale, B.W.; Adams, Layne G.; Bowyer, R.T.
1994-01-01
1. We investigated the functional response of wolves (Canis lupus) to varying abundance of ungulate prey to test the hypothesis that switching from alternate prey to preferred prey results in regulation of a caribou (Rangifer tarandus) population at low densities. 2. We determined prey selection, kill rates, and prey abundance for four wolf packs during three 30-day periods in March 1989, March 1990, November 1990, and created a simple discrete model to evaluate the potential for the expected numerical and observed functional responses of wolves to regulate caribou populations. 3. We observed a quickly decelerating type II functional response that, in the absence of numerical response, implicates an anti-regulatory effect of wolf predation on barren-ground caribou dynamics. 4. There was little potential for regulation caused by the multiplicative effect of increasing functional and numerical responses because of presence of alternative prey. This resulted in high wolf:caribou ratios at low prey densities which precluded the effects of an increasing functional response. 5. Inversely density-dependent predation by other predators, such as bears, reduces the potential for predators to regulate caribou populations at low densities, and small reductions in predation by one predator may have disproportionately large effects on the total predation rate.
Cook, Donald N.; Kang, Hong Soon; Jetten, Anton M.
2015-01-01
In this overview, we provide an update on recent progress made in understanding the mechanisms of action, physiological functions, and roles in disease of retinoic acid related orphan receptors (RORs). We are particularly focusing on their roles in the regulation of adaptive and innate immunity, brain function, retinal development, cancer, glucose and lipid metabolism, circadian rhythm, metabolic and inflammatory diseases and neuropsychiatric disorders. We also summarize the current status of ROR agonists and inverse agonists, including their regulation of ROR activity and their therapeutic potential for management of various diseases in which RORs have been implicated. PMID:26878025
NASA Astrophysics Data System (ADS)
Göschl, Daniel
2018-03-01
We discuss simulation strategies for the massless lattice Schwinger model with a topological term and finite chemical potential. The simulation is done in a dual representation where the complex action problem is solved and the partition function is a sum over fermion loops, fermion dimers and plaquette-occupation numbers. We explore strategies to update the fermion loops coupled to the gauge degrees of freedom and check our results with conventional simulations (without topological term and at zero chemical potential), as well as with exact summation on small volumes. Some physical implications of the results are discussed.
Cocoa and cardiovascular health.
Corti, Roberto; Flammer, Andreas J; Hollenberg, Norman K; Lüscher, Thomas F
2009-03-17
Epidemiological data demonstrate that regular dietary intake of plant-derived foods and beverages reduces the risk of coronary heart disease and stroke. Among many ingredients, cocoa might be an important mediator. Indeed, recent research demonstrates a beneficial effect of cocoa on blood pressure, insulin resistance, and vascular and platelet function. Although still debated, a range of potential mechanisms through which cocoa might exert its benefits on cardiovascular health have been proposed, including activation of nitric oxide and antioxidant and antiinflammatory effects. This review summarizes the available data on the cardiovascular effects of cocoa, outlines potential mechanisms involved in the response to cocoa, and highlights the potential clinical implications associated with its consumption.
On the Evolution of Terrestrial Planets: Implications of Evolutionary Paths and Evolving Lid-States
NASA Astrophysics Data System (ADS)
Weller, M. B.; Lenardic, A.
2015-12-01
Growing geodynamic and geochemical evidence suggests that plate tectonics may not have operated on the early Earth, with both the timing of its onset and the length of its activity far from certain [e.g., 1, 2, and references therein]. Accordingly, information from current observations and processes have the potential of sampling portions of the Earth that has both formed under and been modified by differing tectonic regimes. Here we use coupled 3D mantle convection and planetary tectonics simulations to explore evolutionary paths and planetary tectonic regimes. Early in the geologic lifetime of a terrestrial planet, high mantle temperatures favour stagnant-lids. As radiogenics decay, an initial stagnant-lid may yield into a high temperature mobile-lid state. The transition from an initial stagnant-lid is a function of yield strength, in addition to both internal and surface temperatures. Each lid-state has specific diagnostics and implications for internal parameters, and consequently planetary evolution. The implication within this framework is that a system with a different thermal evolution has the potential to migrate through tectonic regimes at the same 'thermal time' (e.g. temperature), but very different 'temporal times'. This indicate that multiple modes of convection and surface tectonics can potentially operate on a single planetary body at different times in its evolution, as consequence of changing internal parameters, surface temperatures, and differing thermal histories. We will discuss the implications of terrestrial worlds that can alternate, and be offset between multiple tectonic states over giga-year timescales. [1] O'Neill et. al. (2013b) Geol. Soc. London; [2] Weller et al. (2015) EPSL
Williams, Leanne M; Tsang, Tracey W; Clarke, Simon; Kohn, Michael
2010-10-01
There remains a translational gap between research findings and their implementation in clinical practice that applies to attention-deficit/hyperactivity disorder (ADHD), as well as to other major disorders of brain health in childhood, adolescence and adulthood. Research studies have identified potential 'markers' to support diagnostic, functional assessment and treatment decisions, but there is little consensus about these markers. Of these potential markers, cognitive measures of thinking functions, such as sustaining attention and associated electrical brain activity, show promise in complementing the clinical management process. Emerging evidence highlights the relevance of emotional, as well as thinking, functions to ADHD. Here, we outline an integrative neuroscience framework for ADHD that offers one means to bring together cognitive measures of thinking functions with measures of emotion, and their brain and genetic correlates. Understanding these measures and the relationships between them is a first step towards the development of tools that will help to assess the heterogeneity of ADHD, and aid in tailoring treatment choices.
Knop, Karin; Hefner, Dorothée
2018-02-01
Friend or Foe in the Pocket? - The Role of the Individual, Peergroup and Parents for (dys)functional Mobile Phone Use In order to provide consultative support to parents as well as to children and young people, background knowledge regarding the motives of mobile phone use, functions of usage, comprehension of the attraction of this all-round medium also as knowledge about potential hazards are essential. This study offers empirical results about potentials and risks. The peergroup plays an important role for riskful and problematic mobile phone involvement. Parents function as a role model and the explicit parental mediation practices and their impact on the child are in focus. Data was acquired from a quota-sample survey with 500 children between the age of 8 and 14 years and one of their parents, qualitative interviews (20 children and their parents) and eight peergroup-discussions (52 participants). The present paper illuminates the above mentioned aspects and derives implications for guidance practice.
Hajdukiewicz, John R; Vicente, Kim J
2002-01-01
Ecological interface design (EID) is a theoretical framework that aims to support worker adaptation to change and novelty in complex systems. Previous evaluations of EID have emphasized representativeness to enhance generalizability of results to operational settings. The research presented here is complementary, emphasizing experimental control to enhance theory building. Two experiments were conducted to test the impact of functional information and emergent feature graphics on adaptation to novelty and change in a thermal-hydraulic process control microworld. Presenting functional information in an interface using emergent features encouraged experienced participants to become perceptually coupled to the interface and thereby to exhibit higher-level control and more successful adaptation to unanticipated events. The absence of functional information or of emergent features generally led to lower-level control and less success at adaptation, the exception being a minority of participants who compensated by relying on analytical reasoning. These findings may have practical implications for shaping coordination in complex systems and fundamental implications for the development of a general unified theory of coordination for the technical, human, and social sciences. Actual or potential applications of this research include the design of human-computer interfaces that improve safety in complex sociotechnical systems.
The Next G Web: Discernment, Meaning-Making, and the Implications of Web 3.0 for Education
ERIC Educational Resources Information Center
Poore, Megan
2014-01-01
What might Web 3.0 mean for education--that is, education seen as an intellectual and philosophical endeavour where we seek to critique the world and understand our place in it with others? In this paper, I argue that current emphases on the semantic functionality of Web 3.0 have the potential to concomitantly challenge and extend the humanist…
Anne E. Black; Peter Landres
2012-01-01
Current fire policy to restore ecosystem function and resiliency and reduce buildup of hazardous fuels implies a larger future role for fire (both natural and human ignitions) (USDA Forest Service and U.S. Department of the Interior 2000). Yet some fire management (such as building fire line, spike camps, or helispots) potentially causes both short- and longterm...
ERIC Educational Resources Information Center
Van Voorhees, Elizabeth E.; Dedert, Eric A.; Calhoun, Patrick S.; Brancu, Mira; Runnals, Jennifer; Beckham, Jean C.
2012-01-01
Objective: This study examined the relationship among childhood trauma, posttraumatic stress disorder (PTSD) symptoms, and adult social support in a large sample of veterans who served in the military after 09/11/2001, with a specific focus on the potential role of the PTSD avoidance and numbing cluster as intervening in the association between…
Takeshi Ise; Creighton M. Litton; Christian P. Giardina; Akihiko Ito
2010-01-01
Partitioning of gross primary production (GPP) to aboveground versus belowground, to growth versus respiration, and to short versus long�]lived tissues exerts a strong influence on ecosystem structure and function, with potentially large implications for the global carbon budget. A recent meta-analysis of forest ecosystems suggests that carbon partitioning...
Zhao Xiaoying; Ren Jizhou
2007-01-01
The leguminous Caragana species are important components of vegetation in the semi-arid Loess-gully region, China. These shrub species are important for maintaining the dynamics and function of the ecosystem in the region. They are potential plant resources for restoration of degraded ecosystems. The germination responses to temperatures in two...
Rabiller, Gratianne; He, Ji-Wei; Nishijima, Yasuo; Wong, Aaron; Liu, Jialing
2015-01-01
Brain waves resonate from the generators of electrical current and propagate across brain regions with oscillation frequencies ranging from 0.05 to 500 Hz. The commonly observed oscillatory waves recorded by an electroencephalogram (EEG) in normal adult humans can be grouped into five main categories according to the frequency and amplitude, namely δ (1–4 Hz, 20–200 μV), θ (4–8 Hz, 10 μV), α (8–12 Hz, 20–200 μV), β (12–30 Hz, 5–10 μV), and γ (30–80 Hz, low amplitude). Emerging evidence from experimental and human studies suggests that groups of function and behavior seem to be specifically associated with the presence of each oscillation band, although the complex relationship between oscillation frequency and function, as well as the interaction between brain oscillations, are far from clear. Changes of brain oscillation patterns have long been implicated in the diseases of the central nervous system including ischemic stroke, in which the reduction of cerebral blood flow as well as the progression of tissue damage have direct spatiotemporal effects on the power of several oscillatory bands and their interactions. This review summarizes the current knowledge in behavior and function associated with each brain oscillation, and also in the specific changes in brain electrical activities that correspond to the molecular events and functional alterations observed after experimental and human stroke. We provide the basis of the generations of brain oscillations and potential cellular and molecular mechanisms underlying stroke-induced perturbation. We will also discuss the implications of using brain oscillation patterns as biomarkers for the prediction of stroke outcome and therapeutic efficacy. PMID:26516838
Dhahbi, Joseph M; Spindler, Stephen R; Atamna, Hani; Yamakawa, Amy; Guerrero, Noel; Boffelli, Dario; Mote, Patricia; Martin, David I K
2013-02-01
MicroRNAs (miRNAs) function to modulate gene expression, and through this property they regulate a broad spectrum of cellular processes. They can circulate in blood and thereby mediate cell-to-cell communication. Aging involves changes in many cellular processes that are potentially regulated by miRNAs, and some evidence has implicated circulating miRNAs in the aging process. In order to initiate a comprehensive assessment of the role of circulating miRNAs in aging, we have used deep sequencing to characterize circulating miRNAs in the serum of young mice, old mice, and old mice maintained on calorie restriction (CR). Deep sequencing identifies a set of novel miRNAs, and also accurately measures all known miRNAs present in serum. This analysis demonstrates that the levels of many miRNAs circulating in the mouse are increased with age, and that the increases can be antagonized by CR. The genes targeted by this set of age-modulated miRNAs are predicted to regulate biological processes directly relevant to the manifestations of aging including metabolic changes, and the miRNAs themselves have been linked to diseases associated with old age. This finding implicates circulating miRNAs in the aging process, raising questions about their tissues of origin, their cellular targets, and their functional role in metabolic changes that occur with aging.
Animal pee in the sea: consumer-mediated nutrient dynamics in the world's changing oceans.
Allgeier, Jacob E; Burkepile, Deron E; Layman, Craig A
2017-06-01
Humans have drastically altered the abundance of animals in marine ecosystems via exploitation. Reduced abundance can destabilize food webs, leading to cascading indirect effects that dramatically reorganize community structure and shift ecosystem function. However, the additional implications of these top-down changes for biogeochemical cycles via consumer-mediated nutrient dynamics (CND) are often overlooked in marine systems, particularly in coastal areas. Here, we review research that underscores the importance of this bottom-up control at local, regional, and global scales in coastal marine ecosystems, and the potential implications of anthropogenic change to fundamentally alter these processes. We focus attention on the two primary ways consumers affect nutrient dynamics, with emphasis on implications for the nutrient capacity of ecosystems: (1) the storage and retention of nutrients in biomass, and (2) the supply of nutrients via excretion and egestion. Nutrient storage in consumer biomass may be especially important in many marine ecosystems because consumers, as opposed to producers, often dominate organismal biomass. As for nutrient supply, we emphasize how consumers enhance primary production through both press and pulse dynamics. Looking forward, we explore the importance of CDN for improving theory (e.g., ecological stoichiometry, metabolic theory, and biodiversity-ecosystem function relationships), all in the context of global environmental change. Increasing research focus on CND will likely transform our perspectives on how consumers affect the functioning of marine ecosystems. © 2017 John Wiley & Sons Ltd.
Section 3: Quality and Value-Based Requirements
NASA Astrophysics Data System (ADS)
Mylopoulos, John
Traditionally, research and practice in software engineering has focused its attention on specific software qualities, such as functionality and performance. According to this perspective, a system is deemed to be of good quality if it delivers all required functionality (“fitness-for-purpose”) and its performance is above required thresholds. Increasingly, primarily in research but also in practice, other qualities are attracting attention. To facilitate evolution, maintainability and adaptability are gaining popularity. Usability, universal accessibility, innovativeness, and enjoyability are being studied as novel types of non-functional requirements that we do not know how to define, let alone accommodate, but which we realize are critical under some contingencies. The growing importance of the business context in the design of software-intensive systems has also thrust economic value, legal compliance, and potential social and ethical implications into the forefront of requirements topics. A focus on the broader user environment and experience, as well as the organizational and societal implications of system use, thus has become more central to the requirements discourse. This section includes three contributions to this broad and increasingly important topic.
Mehta, Mitul A; Gore-Langton, Emma; Golembo, Nicole; Colvert, Emma; Williams, Steven C R; Sonuga-Barke, Edmund
2010-10-01
Severe deprivation in the first few years of life is associated with multiple difficulties in cognition and behavior. However, the brain basis for these difficulties is poorly understood. Structural and functional neuroimaging studies have implicated limbic system structures as dysfunctional, and one functional imaging study in a heterogeneous group of maltreated individuals has confirmed the presence of abnormalities in the basal ganglia. Based on these studies and known dopaminergic abnormalities from studies in experimental animals using social isolation, we used a task of monetary reward anticipation to examine the functional integrity of brain regions previously shown to be implicated in reward processing. Our sample included a group of adolescents (n = 12) who had experienced global deprivation early in their lives in Romania prior to adoption into UK families. In contrast to a nonadopted comparison group (n = 11), the adoptees did not recruit the striatum during reward anticipation despite comparable performance accuracy and latency. These results show, for the first time, an association between early institutional deprivation and brain reward systems in humans and highlight potential neural vulnerabilities resulting from such exposures.
Bonnelye, Edith; Aubin, Jane E
2013-02-01
Estrogen receptor-related receptor alpha (ERRα) is an orphan nuclear receptor with sequence homology to the estrogen receptors, ERα/β, but it does not bind estrogen. ERRα not only plays a functional role in osteoblasts but also in osteoclasts and chondrocytes. In addition, the ERRs, including ERRα, can be activated by coactivators such as peroxisome proliferator-activated receptor-gamma coactivator-1 (PGC1α and β) and are implicated in adipogenesis, fatty acid oxidation, and oxidative stress defense, suggesting that ERRα-through its activity in bone resorption and adipogenesis--may regulate the insulin and leptin pathways and contribute to aging-related changes in bone and cartilage. In this review, we discuss data on ERRα and its cellular and molecular modes of action, which have broad implications for considering the potential role of this orphan receptor in cartilage and bone endocrine function, on whole-organism physiology, and in the bone aging process. Copyright © 2013 American Society for Bone and Mineral Research.
The Subthalamic Nucleus, Limbic Function, and Impulse Control.
Rossi, P Justin; Gunduz, Aysegul; Okun, Michael S
2015-12-01
It has been well documented that deep brain stimulation (DBS) of the subthalamic nucleus (STN) to address some of the disabling motor symptoms of Parkinson's disease (PD) can evoke unintended effects, especially on non-motor behavior. This observation has catalyzed more than a decade of research concentrated on establishing trends and identifying potential mechanisms for these non-motor effects. While many issues remain unresolved, the collective result of many research studies and clinical observations has been a general recognition of the role of the STN in mediating limbic function. In particular, the STN has been implicated in impulse control and the related construct of valence processing. A better understanding of STN involvement in these phenomena could have important implications for treating impulse control disorders (ICDs). ICDs affect up to 40% of PD patients on dopamine agonist therapy and approximately 15% of PD patients overall. ICDs have been reported to be associated with STN DBS. In this paper we will focus on impulse control and review pre-clinical, clinical, behavioral, imaging, and electrophysiological studies pertaining to the limbic function of the STN.
Probiotics, prebiotics, and the host microbiome: the science of translation.
Petschow, Bryon; Doré, Joël; Hibberd, Patricia; Dinan, Timothy; Reid, Gregor; Blaser, Martin; Cani, Patrice D; Degnan, Fred H; Foster, Jane; Gibson, Glenn; Hutton, John; Klaenhammer, Todd R; Ley, Ruth; Nieuwdorp, Max; Pot, Bruno; Relman, David; Serazin, Andrew; Sanders, Mary Ellen
2013-12-01
Recent advances in our understanding of the community structure and function of the human microbiome have implications for the potential role of probiotics and prebiotics in promoting human health. A group of experts recently met to review the latest advances in microbiota/microbiome research and discuss the implications for development of probiotics and prebiotics, primarily as they relate to effects mediated via the intestine. The goals of the meeting were to share recent advances in research on the microbiota, microbiome, probiotics, and prebiotics, and to discuss these findings in the contexts of regulatory barriers, evolving healthcare environments, and potential effects on a variety of health topics, including the development of obesity and diabetes; the long-term consequences of exposure to antibiotics early in life to the gastrointestinal (GI) microbiota; lactose intolerance; and the relationship between the GI microbiota and the central nervous system, with implications for depression, cognition, satiety, and mental health for people living in developed and developing countries. This report provides an overview of these discussions. © 2013 The Authors. Annals of the New York Academy of Sciences published by Wiley Periodicals, Inc. on behalf of New York Academy of Sciences.
Ethical Implications in the Use of Embryonic and Adult Neural Stem Cells
Ramos-Zúñiga, Rodrigo; González-Pérez, Oscar; Macías-Ornelas, Ana; Capilla-González, Vivian; Quiñones-Hinojosa, Alfredo
2012-01-01
The advent and growth of technological advances have led to new routes of knowledge. Thereby, we currently face new challenges. We have just started to get a glimpse of the structural and functional role of neural stem cells in differentiation and migration processes, the origin of synaptic networks, and subsequent readjustments in specific circuits. A whole range of treatment possibilities originates from this knowledge that potentially can be used for different neurological diseases in humans. Although this is an encouraging scenario, it implies that the human brain is the object of such study, as well as its potential manipulation and transplantation. It is, therefore, pertinent that ethical principles should be followed in such research to have proper balance between what can be done and what should be done, according to every specific context. Hence, it is wise to consider ethical implications in every research project, along with potential clinical applications, under the principle of causing no harm, following risk and benefit rules in decision making and with respect of the human condition as a priority. PMID:22997522
Neural Systems Underlying Individual Differences in Intertemporal Decision-making.
Elton, Amanda; Smith, Christopher T; Parrish, Michael H; Boettiger, Charlotte A
2017-03-01
Excessively choosing immediate over larger future rewards, or delay discounting (DD), associates with multiple clinical conditions. Individual differences in DD likely depend on variations in the activation of and functional interactions between networks, representing possible endophenotypes for associated disorders, including alcohol use disorders (AUDs). Numerous fMRI studies have probed the neural bases of DD, but investigations of large-scale networks remain scant. We addressed this gap by testing whether activation within large-scale networks during Now/Later decision-making predicts individual differences in DD. To do so, we scanned 95 social drinkers (18-40 years old; 50 women) using fMRI during hypothetical choices between small monetary amounts available "today" or larger amounts available later. We identified neural networks engaged during Now/Later choice using independent component analysis and tested the relationship between component activation and degree of DD. The activity of two components during Now/Later choice correlated with individual DD rates: A temporal lobe network positively correlated with DD, whereas a frontoparietal-striatal network negatively correlated with DD. Activation differences between these networks predicted individual differences in DD, and their negative correlation during Now/Later choice suggests functional competition. A generalized psychophysiological interactions analysis confirmed a decrease in their functional connectivity during decision-making. The functional connectivity of these two networks negatively correlates with alcohol-related harm, potentially implicating these networks in AUDs. These findings provide novel insight into the neural underpinnings of individual differences in impulsive decision-making with potential implications for addiction and related disorders in which impulsivity is a defining feature.
Modulation of hippocampal neural plasticity by glucose-related signaling.
Mainardi, Marco; Fusco, Salvatore; Grassi, Claudio
2015-01-01
Hormones and peptides involved in glucose homeostasis are emerging as important modulators of neural plasticity. In this regard, increasing evidence shows that molecules such as insulin, insulin-like growth factor-I, glucagon-like peptide-1, and ghrelin impact on the function of the hippocampus, which is a key area for learning and memory. Indeed, all these factors affect fundamental hippocampal properties including synaptic plasticity (i.e., synapse potentiation and depression), structural plasticity (i.e., dynamics of dendritic spines), and adult neurogenesis, thus leading to modifications in cognitive performance. Here, we review the main mechanisms underlying the effects of glucose metabolism on hippocampal physiology. In particular, we discuss the role of these signals in the modulation of cognitive functions and their potential implications in dysmetabolism-related cognitive decline.
Duchene, Johan; Cayla, Cécile; Vessillier, Sandrine; Scotland, Ramona; Yamashiro, Kazuo; Lecomte, Florence; Syed, Irfan; Vo, Phuong; Marrelli, Alessandra; Pitzalis, Costantino; Cipollone, Francesco; Schanstra, Joost; Bascands, Jean-Loup; Hobbs, Adrian J; Perretti, Mauro; Ahluwalia, Amrita
2009-01-01
OBJECTIVE The pro-inflammatory phenotype induced by low laminar shear stress (LSS) is implicated in atherogenesis. The kinin B1 receptor (B1R), known to be induced by inflammatory stimuli, exerts many pro-inflammatory effects including vasodilatation and leukocyte recruitment. We investigated whether low LSS is a stimulus for endothelial B1R expression and function. METHODS AND RESULTS Human and mouse atherosclerotic plaques expressed high level of B1R mRNA and protein. In addition, B1R expression was upregulated in the aortic arch (low LSS region) of ApoE-/- mice fed a high fat diet compared to vascular regions of high LSS and animals fed normal chow. Of interest, a greater expression of B1R was noticed in endothelial cells from regions of low LSS in aortic arch of ApoE-/- mice. B1R was also upregulated in human umbilical vein endothelial cells (HUVEC) exposed to low LSS (0-2dyn/cm2) compared to physiological LSS (6-10dyn/cm2): an effect similarly evident in murine vascular tissue perfused ex vivo. Functionally, B1R activation increased prostaglandin and CXCL5 expression in cells exposed to low, but not physiological, LSS. IL-1β and ox-LDL induced B1R expression and function in HUVECs, a response substantially enhanced under low LSS conditions and inhibited by blockade of NFκB activation. CONCLUSION Herein, we show that LSS is a major determinant of functional B1R expression in endothelium. Furthermore, whilst physiological high LSS is a powerful repressor of this inflammatory receptor, low LSS at sites of atheroma are associated with substantial upregulation, identifying this receptor as a potential therapeutic target. CONDENSED ABSTRACT Low laminar shear stress (LSS) underlies the pro-inflammatory processes in atherogenesis. Herein, we demonstrate that whilst physiological LSS represses inflammatory kinin B1 receptor (B1R) expression/function, low atherogenic LSS is associated with profound upregulation of both in atherosclerosis in both humans and animal models, highlighting B1R as an exciting potential therapeutic target. PMID:19661485
NASA Astrophysics Data System (ADS)
Price, Mark C.; Kearsley, Anton T.; Burchell, Mark J.; Horz, Friedrich; Cole, Mike J.
2009-06-01
Recent experimental work (Price, M. C. et. al., LPSC XXXX, #1564, 2009) has shown that the lip-to-lip diameter of hypervelocity impact craters at micron-scales (Dp< 10 microns) is a non-linear function of the impactor's diameter (Dp). We present data for monodisperse silica projectiles impacting aluminium-1100 and elemental aluminium at 6.1 kmsec and discuss the implications of this effect for the Stardust fluence calibration for micron-scale particles (which make up the majority of the impactor flux). Hydrocodes have been used to investigate the potential causes of the phenomena and the results are presented.
microRNAs in the regulation of dendritic cell functions in inflammation and atherosclerosis.
Busch, Martin; Zernecke, Alma
2012-08-01
Atherosclerosis has been established as a chronic inflammatory disease of the vessel wall. Among the mononuclear cell types recruited to the lesions, specialized dendritic cells (DCs) have gained increasing attention, and their secretory products and interactions shape the progression of atherosclerotic plaques. The regulation of DC functions by microRNAs (miRNAs) may thus be of primary importance in disease. We here systematically summarize the biogenesis and functions of miRNAs and provide an overview of miRNAs in DCs, their targets, and potential implications for atherosclerosis, with a particular focus on the best characterized miRNAs in DCs, namely, miR-155 and miR-146. MiRNA functions in DCs range from regulation of lipid uptake to cytokine production and T cell responses with a complex picture emerging, in which miRNAs cooperate or antagonize DC behavior, thereby promoting or counterbalancing inflammatory responses. As miRNAs regulate key functions of DCs known to control atherosclerotic vascular disease, their potential as a therapeutic target holds promise and should be attended to in future research.
Role of p21-activated kinases in cardiovascular development and function.
Kelly, Mollie L; Astsaturov, Artyom; Chernoff, Jonathan
2013-11-01
p21-activated kinases (Paks) are a group of six serine/threonine kinases (Pak1-6) that are involved in a variety of biological processes. Recently, Paks, more specifically Pak1, -2, and -4, have been shown to play important roles in cardiovascular development and function in a range of model organisms including zebrafish and mice. These functions include proper morphogenesis and conductance of the heart, cardiac contractility, and development and integrity of the vasculature. The mechanisms underlying these effects are not fully known, but they likely differ among the various Pak isoforms and include both kinase-dependent and -independent functions. In this review, we discuss aspects of Pak function relevant to cardiovascular biology as well as potential therapeutic implications of small-molecule Pak inhibitors in cardiovascular disease.
A constitutively active dioxin/aryl hydrocarbon receptor induces stomach tumors
NASA Astrophysics Data System (ADS)
Andersson, Patrik; McGuire, Jacqueline; Rubio, Carlos; Gradin, Katarina; Whitelaw, Murray L.; Pettersson, Sven; Hanberg, Annika; Poellinger, Lorenz
2002-07-01
The dioxin/aryl hydrocarbon receptor (AhR) functions as a ligand-activated transcription factor regulating transcription of a battery of genes encoding xenobiotic metabolizing enzymes. Known receptor ligands are environmental pollutants including polycyclic aromatic hydrocarbons and polychlorinated dioxins. Loss-of-function (gene-disruption) studies in mice have demonstrated that the AhR is involved in toxic effects of dioxins but have not yielded unequivocal results concerning the physiological function of the receptor. Gain-of-function studies therefore were performed to unravel the biological functions of the AhR. A constitutively active AhR expressed in transgenic mice reduced the life span of the mice and induced tumors in the glandular part of the stomach, demonstrating the oncogenic potential of the AhR and implicating the receptor in regulation of cell proliferation.
Estrogen-cholinergic interactions: Implications for cognitive aging.
Newhouse, Paul; Dumas, Julie
2015-08-01
This article is part of a Special Issue "Estradiol and Cognition". While many studies in humans have investigated the effects of estrogen and hormone therapy on cognition, potential neurobiological correlates of these effects have been less well studied. An important site of action for estrogen in the brain is the cholinergic system. Several decades of research support the critical role of CNS cholinergic systems in cognition in humans, particularly in learning and memory formation and attention. In humans, the cholinergic system has been implicated in many aspects of cognition including the partitioning of attentional resources, working memory, inhibition of irrelevant information, and improved performance on effort-demanding tasks. Studies support the hypothesis that estradiol helps to maintain aspects of attention and verbal and visual memory. Such cognitive domains are exactly those modulated by cholinergic systems and extensive basic and preclinical work over the past several decades has clearly shown that basal forebrain cholinergic systems are dependent on estradiol support for adequate functioning. This paper will review recent human studies from our laboratories and others that have extended preclinical research examining estrogen-cholinergic interactions to humans. Studies examined include estradiol and cholinergic antagonist reversal studies in normal older women, examinations of the neural representations of estrogen-cholinergic interactions using functional brain imaging, and studies of the ability of selective estrogen receptor modulators such as tamoxifen to interact with cholinergic-mediated cognitive performance. We also discuss the implications of these studies for the underlying hypotheses of cholinergic-estrogen interactions and cognitive aging, and indications for prophylactic and therapeutic potential that may exploit these effects. Published by Elsevier Inc.
Franz, Jason R.; Thelen, Darryl G.
2016-01-01
The Achilles tendon (AT) is a complex structure, consisting of distinct fascicle bundles arising from each triceps surae muscle that may act as mechanically independent structures. Advances in tissue imaging are rapidly accelerating our understanding of the complexities of functional Achilles tendon behavior, with potentially important implications for musculoskeletal injury and performance. In this overview of our recent contributions to these efforts, we present the results of complementary experimental and computational approaches to investigate AT behavior during walking and its potential relevance to reduced triceps surae mechanical performance due to aging. Our experimental evidence reveals that older tendons exhibit smaller differences in tissue deformations than young adults between regions of the AT presumed to arise from the gastrocnemius and soleus muscles. These observations are consistent with a reduced capacity for inter-fascicle sliding within the AT, which could have implications for the mechanical independence of the triceps surae muscles. More uniform AT deformations are also correlated with hallmark biomechanical features of elderly gait – namely, a loss of net ankle moment, power, and positive work during push-off. Simulating age-related reductions in the capacity for inter-fascicle sliding in the AT during walking predicts detriments in gastrocnemius muscle-tendon mechanical performance coupled with underlying shifts in fascicle kinematics during push-off. AT compliance, also suspected to vary due to age, systematically modulates those effects. By integrating in vivo imaging with computational modeling, we have gained theoretical insight into multi-scale biomechanical changes due to aging, hypotheses regarding their functional effects, and opportunities for experiments that validate or invalidate these assertions. PMID:27209552
Shimotake, Akihiro; Matsumoto, Riki; Ueno, Taiji; Kunieda, Takeharu; Saito, Satoru; Hoffman, Paul; Kikuchi, Takayuki; Fukuyama, Hidenao; Miyamoto, Susumu; Takahashi, Ryosuke; Ikeda, Akio; Lambon Ralph, Matthew A.
2015-01-01
Semantic memory is a crucial higher cortical function that codes the meaning of objects and words, and when impaired after neurological damage, patients are left with significant disability. Investigations of semantic dementia have implicated the anterior temporal lobe (ATL) region, in general, as crucial for multimodal semantic memory. The potentially crucial role of the ventral ATL subregion has been emphasized by recent functional neuroimaging studies, but the necessity of this precise area has not been selectively tested. The implantation of subdural electrode grids over this subregion, for the presurgical assessment of patients with partial epilepsy or brain tumor, offers the dual yet rare opportunities to record cortical local field potentials while participants complete semantic tasks and to stimulate the functionally identified regions in the same participants to evaluate the necessity of these areas in semantic processing. Across 6 patients, and utilizing a variety of semantic assessments, we evaluated and confirmed that the anterior fusiform/inferior temporal gyrus is crucial in multimodal, receptive, and expressive, semantic processing. PMID:25491206
In search of a viable reaction pathway in the chelation of a metallo-protein
NASA Astrophysics Data System (ADS)
Rose, Frisco; Hodak, Miroslav; Bernholc, Jerry
2010-03-01
Misfolded metallo-proteins are potential causal agents in the onset of neuro-degenerative diseases, such as Alzheimer's and Parkinson's Diseases (PD). Experimental results involving metal chelation have shown significant promise in symptom reduction and misfolding reversal. We explore, through atomistic simulations, potential reaction pathways for the chelation of Cu^2+ from the metal binding site in our representation of a partially misfolded α-synuclein, the protein implicated in PD. Our ab initio simulations use Density Functional Theory (DFT) and nudged elastic band to obtain the minimized energy coordinates of this reaction. Our simulations include ab initio water at the interaction site and in its first solvation shells, while the remainder is fully solvated with orbital-free DFT water representation [1]. Our ongoing studies of viable chelation agents include nicotine, caffeine and other potential reagents, we will review the best case agents in this presentation. [4pt] [1] Hodak M, Lu W, Bernholc J. Hybrid ab initio Kohn-Sham density functional theory/frozen-density orbital-free density functional theory simulation method suitable for biological systems. J. Chem. Phys. 2008 Jan;128(1):014101-9.
Crosswatch: a System for Providing Guidance to Visually Impaired Travelers at Traffic Intersections
Coughlan, James M.; Shen, Huiying
2013-01-01
Purpose This paper describes recent progress on the “Crosswatch” project, a smartphone-based system developed for providing guidance to blind and visually impaired travelers at traffic intersections. Building on past work on Crosswatch functionality to help the user achieve proper alignment with the crosswalk and read the status of walk lights to know when it is time to cross, we outline the directions Crosswatch is now taking to help realize its potential for becoming a practical system: namely, augmenting computer vision with other information sources, including geographic information systems (GIS) and sensor data, and inferring the user's location much more precisely than is possible through GPS alone, to provide a much larger range of information about traffic intersections to the pedestrian. Design/methodology/approach The paper summarizes past progress on Crosswatch and describes details about the development of new Crosswatch functionalities. One such functionality, which is required for determination of the user's precise location, is studied in detail, including the design of a suitable user interface to support this functionality and preliminary tests of this interface with visually impaired volunteer subjects. Findings The results of the tests of the new Crosswatch functionality demonstrate that the functionality is feasible in that it is usable by visually impaired persons. Research limitations/implications While the tests that were conducted of the new Crosswatch functionality are preliminary, the results of the tests have suggested several possible improvements, to be explored in the future. Practical implications The results described in this paper suggest that the necessary technologies used by the Crosswatch system are rapidly maturing, implying that the system has an excellent chance of becoming practical in the near future. Originality/value The paper addresses an innovative solution to a key problem faced by blind and visually impaired travelers, which has the potential to greatly improve independent travel for these individuals. PMID:24353745
Does robotics improve minimally invasive rectal surgery? Functional and oncological implications.
Guerra, Francesco; Pesi, Benedetta; Amore Bonapasta, Stefano; Perna, Federico; Di Marino, Michele; Annecchiarico, Mario; Coratti, Andrea
2016-02-01
Robot-assisted surgery has been reported to be a safe and effective alternative to conventional laparoscopy for the treatment of rectal cancer in a minimally invasive manner. Nevertheless, substantial data concerning functional outcomes and long-term oncological adequacy is still lacking. We aimed to assess the current role of robotics in rectal surgery focusing on patients' functional and oncological outcomes. A comprehensive review was conducted to search articles published in English up to 11 September 2015 concerning functional and/or oncological outcomes of patients who received robot-assisted rectal surgery. All relevant papers were evaluated on functional implications such as postoperative sexual and urinary dysfunction and oncological outcomes. Robotics showed a general trend towards lower rates of sexual and urinary postoperative dysfunction and earlier recovery compared with laparoscopy. The rates of 3-year local recurrence, disease-free survival and overall survival of robotic-assisted rectal surgery compared favourably with those of laparoscopy. This study fails to provide solid evidence to draw definitive conclusions on whether robotic systems could be useful in ameliorating the outcomes of minimally invasive surgery for rectal cancer. However, the available data suggest potential advantages over conventional laparoscopy with reference to functional outcomes. © 2016 Chinese Medical Association Shanghai Branch, Chinese Society of Gastroenterology, Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine and John Wiley & Sons Australia, Ltd.
Magnetic resonance imaging based functional imaging in paediatric oncology.
Manias, Karen A; Gill, Simrandip K; MacPherson, Lesley; Foster, Katharine; Oates, Adam; Peet, Andrew C
2017-02-01
Imaging is central to management of solid tumours in children. Conventional magnetic resonance imaging (MRI) is the standard imaging modality for tumours of the central nervous system (CNS) and limbs and is increasingly used in the abdomen. It provides excellent structural detail, but imparts limited information about tumour type, aggressiveness, metastatic potential or early treatment response. MRI based functional imaging techniques, such as magnetic resonance spectroscopy, diffusion and perfusion weighted imaging, probe tissue properties to provide clinically important information about metabolites, structure and blood flow. This review describes the role of and evidence behind these functional imaging techniques in paediatric oncology and implications for integrating them into routine clinical practice. Copyright © 2016 Elsevier Ltd. All rights reserved.
Shetty, Mahesh Shivarama; Sharma, Mahima; Sajikumar, Sreedharan
2017-02-01
Aging is associated with decline in cognitive functions, prominently in the memory consolidation and association capabilities. Hippocampus plays a crucial role in the formation and maintenance of long-term associative memories, and a significant body of evidence shows that impairments in hippocampal function correlate with aging-related memory loss. A number of studies have implicated alterations in hippocampal synaptic plasticity, such as long-term potentiation (LTP), in age-related cognitive decline although exact mechanisms underlying are not completely clear. Zinc deficiency and the resultant adverse effects on cognition have been well studied. However, the role of excess of zinc in synaptic plasticity, especially in aging, is not addressed well. Here, we have investigated the hippocampal zinc levels and the impairments in synaptic plasticity, such as LTP and synaptic tagging and capture (STC), in the CA1 region of acute hippocampal slices from 82- to 84-week-old male Wistar rats. We report increased zinc levels in the hippocampus of aged rats and also deficits in the tetani-induced and dopaminergic agonist-induced late-LTP and STC. The observed deficits in synaptic plasticity were restored upon chelation of zinc using a cell-permeable chelator. These data suggest that functional plasticity and associativity can be successfully established in aged neural networks by chelating zinc with cell-permeable chelating agents. © 2016 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.
Mast cells: potential positive and negative roles in tumor biology.
Marichal, Thomas; Tsai, Mindy; Galli, Stephen J
2013-11-01
Mast cells are immune cells that reside in virtually all vascularized tissues. Upon activation by diverse mechanisms, mast cells can secrete a broad array of biologically active products that either are stored in the cytoplasmic granules of the cells (e.g., histamine, heparin, various proteases) or are produced de novo upon cell stimulation (e.g., prostaglandins, leukotrienes, cytokines, chemokines, and growth factors). Mast cells are best known for their effector functions during anaphylaxis and acute IgE-associated allergic reactions, but they also have been implicated in a wide variety of processes that maintain health or contribute to disease. There has been particular interest in the possible roles of mast cells in tumor biology. In vitro studies have shown that mast cells have the potential to influence many aspects of tumor biology, including tumor development, tumor-induced angiogenesis, and tissue remodeling, and the shaping of adaptive immune responses to tumors. Yet, the actual contributions of mast cells to tumor biology in vivo remain controversial. Here, we review some basic features of mast cell biology with a special emphasis on those relevant to their potential roles in tumors. We discuss how using in vivo tumor models in combination with models in which mast cell function can be modulated has implicated mast cells in the regulation of host responses to tumors. Finally, we summarize data from studies of human tumors that suggest either beneficial or detrimental roles for mast cells in tumors. ©2013 AACR.
Brozovich, F.V.; Nicholson, C.J.; Degen, C.V.; Gao, Yuan Z.; Aggarwal, M.
2016-01-01
The smooth muscle cell directly drives the contraction of the vascular wall and hence regulates the size of the blood vessel lumen. We review here the current understanding of the molecular mechanisms by which agonists, therapeutics, and diseases regulate contractility of the vascular smooth muscle cell and we place this within the context of whole body function. We also discuss the implications for personalized medicine and highlight specific potential target molecules that may provide opportunities for the future development of new therapeutics to regulate vascular function. PMID:27037223
Group I p21-activated kinases: emerging roles in immune function and viral pathogenesis.
Pacheco, Almudena; Chernoff, Jonathan
2010-01-01
Group I p21-activated kinases are a highly conserved three-member family of serine/threonine kinases that act as key effectors for the small GTPases Cdc42 and Rac. In man, these enzymes have been implicated in a wide range of biological processes and are beginning to draw the attention of the pharmaceutical industry as potential therapeutic targets in cancer and in inflammatory processes. In this review, we summarize basic properties of group I Paks and discuss recently uncovered roles for these kinases in immune function and in viral infection.
Motivations and usage patterns of Weibo.
Zhang, Lixuan; Pentina, Iryna
2012-06-01
Referred to as "Weibo," microblogging in China has witnessed an exponential growth. In addition to the Twitter-like functionality, Weibo allows rich media uploads into user feeds, provides threaded comments, and offers applications, games, and Weibo medals. This expanded functionality, as well as the observed differences in trending content, suggests potentially different user motivations to join Weibo and their usage patterns compared to Twitter. This pioneering study identifies dominant Weibo user motivations and their effects on usage patterns. We discuss the findings of an online survey of 234 Weibo users and suggest managerial implications and future research directions.
The Benefits of High Intensity Functional Training (HIFT) Fitness Programs for Military Personnel
Haddock, Christopher K.; Poston, Walker S.C.; Heinrich, Katie M.; Jahnke, Sara A.; Jitnarin, Nattinee
2016-01-01
High intensity functional training (HIFT) programs are designed to address multiple fitness domains, potentially providing improved physical and mental readiness in a changing operational environment. Programs consistent with HIFT principals such as CrossFit, SEALFIT and the US Marine Corps’ High Intensity Tactical Training (HITT) program are increasingly popular among military personnel. This article reviews the practical, health, body composition, and military fitness implications of HIFT exercise programs. We conclude that, given the unique benefits of HIFT, the military should consider evaluating whether these programs should be the standard for military fitness training. PMID:27849484
Physiological and ecological implications of ocean deoxygenation for vision in marine organisms
NASA Astrophysics Data System (ADS)
McCormick, Lillian R.; Levin, Lisa A.
2017-08-01
Climate change has induced ocean deoxygenation and exacerbated eutrophication-driven hypoxia in recent decades, affecting the physiology, behaviour and ecology of marine organisms. The high oxygen demand of visual tissues and the known inhibitory effects of hypoxia on human vision raise the questions if and how ocean deoxygenation alters vision in marine organisms. This is particularly important given the rapid loss of oxygen and strong vertical gradients in oxygen concentration in many areas of the ocean. This review evaluates the potential effects of low oxygen (hypoxia) on visual function in marine animals and their implications for marine biota under current and future ocean deoxygenation based on evidence from terrestrial and a few marine organisms. Evolutionary history shows radiation of eye designs during a period of increasing ocean oxygenation. Physiological effects of hypoxia on photoreceptor function and light sensitivity, in combination with morphological changes that may occur throughout ontogeny, have the potential to alter visual behaviour and, subsequently, the ecology of marine organisms, particularly for fish, cephalopods and arthropods with `fast' vision. Visual responses to hypoxia, including greater light requirements, offer an alternative hypothesis for observed habitat compression and shoaling vertical distributions in visual marine species subject to ocean deoxygenation, which merits further investigation. This article is part of the themed issue 'Ocean ventilation and deoxygenation in a warming world'.
Turner, Jill R; Ortinski, Pavel I; Sherrard, Rachel M; Kellar, Kenneth J
2011-12-01
Although recent studies have delineated the specific nicotinic subtypes present in the mammalian cerebellum, very little is known about their location or function within the cerebellum. This is of increased interest since nicotinic receptors (nAChRs) in the cerebellum have recently been implicated in the pathology of autism spectrum disorders. To begin to better understand the roles of these heteromeric nAChRs in the cerebellar circuitry and their therapeutic potential as targets for drug development, we used various chemical and stereotaxic lesion models in conjunction with slice electrophysiology to examine how specific heteromeric nAChR subtypes may influence the surrounding cerebellar circuitry. Using subunit-specific immunoprecipitation of radiolabeled nAChRs in the cerebella following N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride, p-chloroamphetamine, and pendunculotomy lesions, we show that most, if not all, cerebellar nicotinic receptors are present in cells within the cerebellum itself and not in extracerebellar afferents. Furthermore, we demonstrate that the β4-containing, but not the β2-containing, nAChRs intrinsic to the cerebellum can regulate inhibitory synaptic efficacy at two major classes of cerebellar neurons. These tandem findings suggest that nAChRs may present a potential drug target for disorders involving the cerebellum.
Turner, Jill R.; Ortinski, Pavel I.; Sherrard, Rachel M.
2016-01-01
Although recent studies have delineated the specific nicotinic subtypes present in the mammalian cerebellum, very little is known about their location or function within the cerebellum. This is of increased interest since nicotinic receptors (nAChRs) in the cerebellum have recently been implicated in the pathology of autism spectrum disorders. To begin to better understand the roles of these heteromeric nAChRs in the cerebellar circuitry and their therapeutic potential as targets for drug development, we used various chemical and stereotaxic lesion models in conjunction with slice electrophysiology to examine how specific heteromeric nAChR subtypes may influence the surrounding cerebellar circuitry. Using subunit-specific immunoprecipitation of radiolabeled nAChRs in the cerebella following N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine hydrochloride, p-chloroamphetamine, and pendunculotomy lesions, we show that most, if not all, cerebellar nicotinic receptors are present in cells within the cerebellum itself and not in extracerebellar afferents. Furthermore, we demonstrate that the β4-containing, but not the β2-containing, nAChRs intrinsic to the cerebellum can regulate inhibitory synaptic efficacy at two major classes of cerebellar neurons. These tandem findings suggest that nAChRs may present a potential drug target for disorders involving the cerebellum. PMID:21562921
NASA Technical Reports Server (NTRS)
Kohn, W.
1983-01-01
It is shown that if n(r) is the discrete density on a lattice (enclosed in a finite box) associated with a nondegenerate ground state in an external potential v(r) (i.e., is 'v-representable'), then the density n(r) + mu(r), with m(r) arbitrary (apart from trivial constraints) and mu small enough, is also associated with a nondegenerate ground state in an external potential v'(r) near v(r); i.e., n(r) + m(r) is also v-representable. Implications for the Hohenberg-Kohn variational principle and the Kohn-Sham equations are discussed.
Unacknowledged Rape: The Influences of Child Sexual Abuse and Personality Traits.
Wilson, Laura C; Scarpa, Angela
2015-01-01
Evidence supports that the majority of young women who experience sexual victimization that meets the legal definition of rape do not label their experiences as rape--this has been termed unacknowledged rape. In a sample of 77 young adult women, the odds of unacknowledged rape significantly increased as a function of less severe child sexual abuse histories and greater levels of dysfunctional personality traits. Potential explanations for these findings as well as clinical implications are discussed. Because of the potential psychological and societal consequences of unacknowledged rape, it is vital that researchers continue to examine this phenomenon.
Kang, Chang Moo; Babicky, Michele L; Lowy, Andrew M
2014-03-01
Pancreatic cancer remains a devastating disease with a mortality rate that has not changed substantially in decades. Novel therapies are therefore desperately needed. The RON receptor tyrosine kinase has been identified as an important mediator of KRAS oncogene addiction and is overexpressed in the majority of pancreatic cancers. Preclinical studies show that inhibition of RON function decreases pancreatic cancer cell migration, invasion, and survival and can sensitize pancreatic cancer cells to chemotherapy. This article reviews the current state of knowledge regarding RON biology and pancreatic cancer and discusses its potential as a therapeutic target.
Benskey, Matthew J; Perez, Ruth G; Manfredsson, Fredric P
2016-05-01
The aggregation of alpha synuclein (α-syn) is a neuropathological feature that defines a spectrum of disorders collectively termed synucleinopathies, and of these, Parkinson's disease (PD) is arguably the best characterized. Aggregated α-syn is the primary component of Lewy bodies, the defining pathological feature of PD, while mutations or multiplications in the α-syn gene result in familial PD. The high correlation between α-syn burden and PD has led to the hypothesis that α-syn aggregation produces toxicity through a gain-of-function mechanism. However, α-syn has been implicated to function in a diverse range of essential cellular processes such as the regulation of neurotransmission and response to cellular stress. As such, an alternative hypothesis with equal explanatory power is that the aggregation of α-syn results in toxicity because of a toxic loss of necessary α-syn function, following sequestration of functional forms α-syn into insoluble protein aggregates. Within this review, we will provide an overview of the literature linking α-syn to PD and the knowledge gained from current α-syn-based animal models of PD. We will then interpret these data from the viewpoint of the α-syn loss-of-function hypothesis and provide a potential mechanistic model by which loss of α-syn function could result in at least some of the neurodegeneration observed in PD. By providing an alternative perspective on the etiopathogenesis of PD and synucleinopathies, this may reveal alternative avenues of research in order to identify potential novel therapeutic targets for disease modifying strategies. The correlation between α-synuclein burden and Parkinson's disease pathology has led to the hypothesis that α-synuclein aggregation produces toxicity through a gain-of-function mechanism. However, in this review, we discuss data supporting the alternative hypothesis that the aggregation of α-synuclein results in toxicity because of loss of necessary α-synuclein function at the presynaptic terminal, following sequestration of functional forms of α-synuclein into aggregates. © 2016 The Authors. Journal of Neurochemistry published by John Wiley & Sons Ltd on behalf of International Society for Neurochemistry.
Shyness and Vocabulary: The Roles of Executive Functioning and Home Environmental Stimulation
Nayena Blankson, A.; O’Brien, Marion; Leerkes, Esther M.; Marcovitch, Stuart; Calkins, Susan D.
2010-01-01
Although shyness has often been found to be negatively related to vocabulary, few studies have examined the processes that produce or modify this relation. The present study examined executive functioning skills and home environmental stimulation as potential mediating and moderating mechanisms. A sample of 3.5-year-old children (N=254) were administered executive functioning tasks and a vocabulary test during a laboratory visit. Mothers completed questionnaires assessing child shyness and home environmental stimulation. Our primary hypothesis was that executive functioning mediates the association between shyness and vocabulary, and home environmental stimulation moderates the relation between executive functioning and vocabulary. Alternative hypotheses were also tested. Results indicated that children with better executive functioning skills developed stronger vocabularies when reared in more, versus less, stimulating environments. Implications of these results are discussed in terms of the role of shyness, executive functioning, and home environmental stimulation in early vocabulary development. PMID:22096267
Saas, Philippe; Varin, Alexis; Perruche, Sylvain; Ceroi, Adam
2017-01-01
There are more and more data concerning the role of cellular metabolism in innate immune cells, such as macrophages or conventional dendritic cells. However, few data are available currently concerning plasmacytoid dendritic cells (PDC), another type of innate immune cells. These cells are the main type I interferon (IFN) producing cells, but they also secrete other pro-inflammatory cytokines (e.g., tumor necrosis factor or interleukin [IL]-6) or immunomodulatory factors (e.g., IL-10 or transforming growth factor-β). Through these functions, PDC participate in antimicrobial responses or maintenance of immune tolerance, and have been implicated in the pathophysiology of several autoimmune diseases, as well as in tumor immune escape mechanisms. Recent data support the idea that the glycolytic pathway (or glycolysis), as well as lipid metabolism (including both cholesterol and fatty acid metabolism) may impact some innate immune functions of PDC or may be involved in these functions after Toll-like receptor (TLR) 7/9 triggering. The kinetics of glycolysis after TLR7/9 triggering may differ between human and murine PDC. In mouse PDC, metabolism changes promoted by TLR7/9 activation may depend on an autocrine/paracrine loop, implicating type I IFN and its receptor IFNAR. This could explain a delayed glycolysis in mouse PDC. Moreover, PDC functions can be modulated by the metabolism of cholesterol and fatty acids. This may occur via the production of lipid ligands that activate nuclear receptors (e.g., liver X receptor [LXR]) in PDC or through limiting intracellular cholesterol pool size (by statin or LXR agonist treatment) in these cells. Finally, lipid-activated nuclear receptors (i.e., LXR or peroxisome proliferator activated receptor) may also directly interact with pro-inflammatory transcription factors, such as NF-κB. Here, we discuss how glycolysis and lipid metabolism may modulate PDC functions and how this may be harnessed in pathological situations where PDC play a detrimental role.
Saas, Philippe; Varin, Alexis; Perruche, Sylvain; Ceroi, Adam
2017-01-01
There are more and more data concerning the role of cellular metabolism in innate immune cells, such as macrophages or conventional dendritic cells. However, few data are available currently concerning plasmacytoid dendritic cells (PDC), another type of innate immune cells. These cells are the main type I interferon (IFN) producing cells, but they also secrete other pro-inflammatory cytokines (e.g., tumor necrosis factor or interleukin [IL]-6) or immunomodulatory factors (e.g., IL-10 or transforming growth factor-β). Through these functions, PDC participate in antimicrobial responses or maintenance of immune tolerance, and have been implicated in the pathophysiology of several autoimmune diseases, as well as in tumor immune escape mechanisms. Recent data support the idea that the glycolytic pathway (or glycolysis), as well as lipid metabolism (including both cholesterol and fatty acid metabolism) may impact some innate immune functions of PDC or may be involved in these functions after Toll-like receptor (TLR) 7/9 triggering. The kinetics of glycolysis after TLR7/9 triggering may differ between human and murine PDC. In mouse PDC, metabolism changes promoted by TLR7/9 activation may depend on an autocrine/paracrine loop, implicating type I IFN and its receptor IFNAR. This could explain a delayed glycolysis in mouse PDC. Moreover, PDC functions can be modulated by the metabolism of cholesterol and fatty acids. This may occur via the production of lipid ligands that activate nuclear receptors (e.g., liver X receptor [LXR]) in PDC or through limiting intracellular cholesterol pool size (by statin or LXR agonist treatment) in these cells. Finally, lipid-activated nuclear receptors (i.e., LXR or peroxisome proliferator activated receptor) may also directly interact with pro-inflammatory transcription factors, such as NF-κB. Here, we discuss how glycolysis and lipid metabolism may modulate PDC functions and how this may be harnessed in pathological situations where PDC play a detrimental role. PMID:28580131
Benson, M
2016-03-01
Many patients with common diseases do not respond to treatment. This is a key challenge to modern health care, which causes both suffering and enormous costs. One important reason for the lack of treatment response is that common diseases are associated with altered interactions between thousands of genes, in combinations that differ between subgroups of patients who do or do not respond to a given treatment. Such subgroups, or even distinct disease entities, have been described recently in asthma, diabetes, autoimmune diseases and cancer. High-throughput techniques (omics) allow identification and characterization of such subgroups or entities. This may have important clinical implications, such as identification of diagnostic markers for individualized medicine, as well as new therapeutic targets for patients who do not respond to existing drugs. For example, whole-genome sequencing may be applied to more accurately guide treatment of neurodevelopmental diseases, or to identify drugs specifically targeting mutated genes in cancer. A study published in 2015 showed that 28% of hepatocellular carcinomas contained mutated genes that potentially could be targeted by drugs already approved by the US Food and Drug Administration. A translational study, which is described in detail, showed how combined omics, computational, functional and clinical studies could identify and validate a novel diagnostic and therapeutic candidate gene in allergy. Another important clinical implication is the identification of potential diagnostic markers and therapeutic targets for predictive and preventative medicine. By combining computational and experimental methods, early disease regulators may be identified and potentially used to predict and treat disease before it becomes symptomatic. Systems medicine is an emerging discipline, which may contribute to such developments through combining omics with computational, functional and clinical studies. The aims of this review are to provide a brief introduction to systems medicine and discuss how it may contribute to the clinical implementation of individualized treatment, using clinically relevant examples. © 2015 The Association for the Publication of the Journal of Internal Medicine.
Rehabilitation as "destination triage": a critical examination of discharge planning.
Durocher, Evelyne; Gibson, Barbara E; Rappolt, Susan
2017-06-01
In this paper we examine how the intersection of various social and political influences shapes discharge planning and rehabilitation practices in ways that may not meet the espoused aims of rehabilitation programs or the preferences of older adults and their families. Taking a critical bioethics perspective, we used microethnographic case study methods to examine discharge-planning processes in a well-established older adult inpatient rehabilitation setting in Canada. The data included observations of discharge-planning family conferences and semi-structured interviews conducted with older adults facing discharge, their family members and rehabilitation professionals involved in discharge planning. From the time of admission, a contextual push to focus on discharge superseded program aims of providing interventions to increase older adults' functional capabilities. Professionals' primary commitment to safety limited consideration of discharge options and resulted in costly and potentially unnecessary recommendations for 24-hour care. The resulting "rehabilitation" stay was more akin to an extended process of "destination triage" biased towards the promotion of physical safety than optimizing functioning. The resulting reduction of rehabilitation into "destination triage" has significant social, financial and occupational implications for older adults and their families, and broader implications for healthcare services and overarching healthcare systems. Implications for Rehabilitation Current trends promoting consideration of discharge planning from the point of admission and prioritizing physical safety are shifting the focus of rehabilitation away from interventions to maximize recovery of function, which are the stated aims of rehabilitation. Such practices furthermore promote assessments to determine prognosis early in the rehabilitation stay when accurate prognosis is difficult, which can lead to overly conservative recommendations for discharge from rehabilitation services, thus further negating the impact of rehabilitation. Further work is required to examine the social, occupational and functional implications of superseding rehabilitation interventions to maximize capabilities with practices that prioritize safety over quality of life for older adults and their family members.
Hemiplegic shoulder pain: implications for occupational therapy treatment.
Gilmore, Paula E; Spaulding, Sandi J; Vandervoort, Anthony A
2004-02-01
Hemiplegic shoulder pain is common after stroke causing hemiplegia. It adversely affects the recovery of arm function and independence in activities of daily living. Subluxation, abnormal tone and limited range of motion or capsular constrictions have been reported as potential causes. Other factors such as rotator cuff tears, brachial plexus injury, shoulder-hand syndrome and other pre-existing pathological conditions may also be associated with hemiplegic shoulder pain. The etiology remains unclear, but hemiplegic shoulder pain may result from a combination of the above factors. This literature review examines the possible causes of hemiplegic shoulder pain and discusses the implications for occupational therapy treatment. Occupational therapy interventions include proper positioning, facilitation of movement through purposeful therapeutic activities, increasing passive range of motion, implementation of external supports and treatment of shoulder-hand syndrome. Understanding the processes involved will assist with effective assessment, treatment and prevention of hemiplegic shoulder pain. This will facilitate clients' participation in rehabilitation programs and move them towards attainment of optimal function.
Vitamin D Axis in Inflammatory Bowel Diseases: Role, Current Uses and Future Perspectives
Del Pinto, Rita; Ferri, Claudio; Cominelli, Fabio
2017-01-01
Increasing evidence supports the concept that the vitamin D axis possesses immunoregulatory functions, with vitamin D receptor (VDR) status representing the major determinant of vitamin D’s pleiotropic effects. Vitamin D promotes the production of anti-microbial peptides, including β-defensins and cathelicidins, the shift towards Th2 immune responses, and regulates autophagy and epithelial barrier integrity. Impairment of vitamin D-mediated pathways are associated with chronic inflammatory conditions, including inflammatory bowel diseases (IBD). Interestingly, inhibition of vitamin D pathways results in dysbiosis of the gut microbiome, which has mechanistically been implicated in the development of IBD. Herein, we explore the role of the vitamin D axis in immune-mediated diseases, with particular emphasis on its interplay with the gut microbiome in the pathogenesis of IBD. The potential clinical implications and therapeutic relevance of this interaction will also be discussed, including optimizing VDR function, both with vitamin D analogues and probiotics, which may represent a complementary approach to current IBD treatments. PMID:29112157
The neovasculature homing motif NGR: more than meets the eye
Curnis, Flavio; Arap, Wadih; Pasqualini, Renata
2008-01-01
A growing body of evidence suggests that peptides containing the Asn-Gly-Arg (NGR) motif can selectively recognize tumor neovasculature and can be used, therefore, for ligand-directed targeted delivery of various drugs and particles to tumors or to other tissues with an angiogenesis component. The neovasculature binding properties of these peptides rely on the interaction with an endothelium-associated form of aminopeptidase N (CD13), an enzyme that has been implicated in angiogenesis and tumor growth. Recent studies have shown that NGR can rapidly convert to isoaspartate-glycine-arginine (isoDGR) by asparagine deamidation, generating αvβ3 ligands capable of affecting endothelial cell functions and tumor growth. This review focuses on structural and functional properties of the NGR motif and its application in drug development for angiogenesis-dependent diseases. Furthermore, we discuss the time-dependent transition of NGR to isoDGR in natural proteins, such as fibronectins, and its potential role of as a “molecular timer” for generating new binding sites for integrins impli-cated in angiogenesis. PMID:18574027
Disaggregation of small, cohesive rubble pile asteroids due to YORP
NASA Astrophysics Data System (ADS)
Scheeres, D. J.
2018-04-01
The implication of small amounts of cohesion within relatively small rubble pile asteroids is investigated with regard to their evolution under the persistent presence of the YORP effect. We find that below a characteristic size, which is a function of cohesive strength, density and other properties, rubble pile asteroids can enter a "disaggregation phase" in which they are subject to repeated fissions after which the formation of a stabilizing binary system is not possible. Once this threshold is passed rubble pile asteroids may be disaggregated into their constituent components within a finite time span. These constituent components will have their own spin limits - albeit potentially at a much higher spin rate due to the greater strength of a monolithic body. The implications of this prediction are discussed and include modification of size distributions, prevalence of monolithic bodies among meteoroids and the lifetime of small rubble pile bodies in the solar system. The theory is then used to place constraints on the strength of binary asteroids characterized as a function of their type.
Ruttle, Paula L.; Shirtcliff, Elizabeth A.; Essex, Marilyn J.; Susman, Elizabeth J.
2014-01-01
Substantial research has implicated the hypothalamic-pituitary-adrenal (HPA) and hypothalamic-pituitary-gonadal (HPG) axes independently in adolescent mental health problems, though this literature remains largely inconclusive. Given the cross-talk between the HPA and HPG axes and their increased activation in adolescence, a dual-axis approach that examines both axes simultaneously is proposed to predict the emergence and persistence of adolescent mental health problems. After briefly orienting readers to HPA and HPG axis functioning, we review the literature examining associations between hormone levels and changes with behavior during adolescence. Then, we provide a review of the literature supporting examination of both axes simultaneously and present the limited research that has taken a dual-axis approach. We propose future directions including consideration of between-person and within-person approaches to address questions of correlated changes in HPA and HPG hormones. Potential moderators are considered to increase understanding of the nuanced hormone–behavior associations during key developmental transitions. PMID:24729154
The Influence of Nicotinamide on Health and Disease in the Central Nervous System
Fricker, Rosemary A; Green, Emma L; Jenkins, Stuart I; Griffin, Síle M
2018-01-01
Nicotinamide, the amide form of vitamin B3 (niacin), has long been associated with neuronal development, survival, and function in the central nervous system (CNS), being implicated in both neuronal death and neuroprotection. Here, we summarise a body of research investigating the role of nicotinamide in neuronal health within the CNS, with a focus on studies that have shown a neuroprotective effect. Nicotinamide appears to play a role in protecting neurons from traumatic injury, ischaemia, and stroke, as well as being implicated in 3 key neurodegenerative conditions: Alzheimer’s, Parkinson’s, and Huntington’s diseases. A key factor is the bioavailability of nicotinamide, with low concentrations leading to neurological deficits and dementia and high levels potentially causing neurotoxicity. Finally, nicotinamide’s potential mechanisms of action are discussed, including the general maintenance of cellular energy levels and the more specific inhibition of molecules such as the nicotinamide adenine dinucleotide-dependent deacetylase, sirtuin 1 (SIRT1). PMID:29844677
The functional role of long non-coding RNA in digestive system carcinomas.
Wang, Guang-Yu; Zhu, Yuan-Yuan; Zhang, Yan-Qiao
2014-09-01
In recent years, long non-coding RNAs (lncRNAs) are emerging as either oncogenes or tumor suppressor genes. Recent evidences suggest that lncRNAs play a very important role in digestive system carcinomas. However, the biological function of lncRNAs in the vast majority of digestive system carcinomas remains unclear. Recently, increasing studies has begun to explore their molecular mechanisms and regulatory networks that they are implicated in tumorigenesis. In this review, we highlight the emerging functional role of lncRNAs in digestive system carcinomas. It is becoming clear that lncRNAs will be exciting and potentially useful for diagnosis and treatment of digestive system carcinomas, some of these lncRNAs might function as both diagnostic markers and the treatment targets of digestive system carcinomas.
Skeletal and cardiac muscle pericytes: Functions and therapeutic potential
Murray, Iain R.; Baily, James E.; Chen, William C.W.; Dar, Ayelet; Gonzalez, Zaniah N.; Jensen, Andrew R.; Petrigliano, Frank A.; Deb, Arjun; Henderson, Neil C.
2017-01-01
Pericytes are periendothelial mesenchymal cells residing within the microvasculature. Skeletal muscle and cardiac pericytes are now recognized to fulfill an increasing number of functions in normal tissue homeostasis, including contributing to microvascular function by maintaining vessel stability and regulating capillary flow. In the setting of muscle injury, pericytes contribute to a regenerative microenvironment through release of trophic factors and by modulating local immune responses. In skeletal muscle, pericytes also directly enhance tissue healing by differentiating into myofibers. Conversely, pericytes have also been implicated in the development of disease states, including fibrosis, heterotopic ossication and calcification, atherosclerosis, and tumor angiogenesis. Despite increased recognition of pericyte heterogeneity, it is not yet clear whether specific subsets of pericytes are responsible for individual functions in skeletal and cardiac muscle homeostasis and disease. PMID:27595928
Asp, Erik; Manzel, Kenneth; Koestner, Bryan; Denburg, Natalie L.; Tranel, Daniel
2013-01-01
The False Tagging Theory (FTT) is a neuroanatomical model of belief and doubt processes that proposes a single, unique function for the prefrontal cortex. Here, we review evidence pertaining to the FTT, the implications of the FTT regarding fractionation of the prefrontal cortex, and the potential benefits of the FTT for new neuroanatomical conceptualizations of executive functions. The FTT provides a parsimonious account that may help overcome theoretical problems with prefrontal cortex mediated executive control such as the homunculus critique. Control in the FTT is examined via the “heuristics and biases” psychological framework for human judgment. The evidence indicates that prefrontal cortex mediated doubting is at the core of executive functioning and may explain some biases of intuitive judgments. PMID:23745103
Jarajapu, Yagna P R
2017-01-01
In recent years, previously unknown functions have been conferred to the RAAS and have been explored in mechanistic studies and disease models. Implication of bone marrow stem/progenitor cells in the cardiovascular protective or detrimental effects of RAAS is a prominent advancement because of the translational significance. Selected members of RAAS are now known to modulate migration, proliferation, and mobilization of bone marrow cells in response to ischemic insult, which are sensitive indicators of vascular repair-relevant functions. In this Chapter, protocols for most frequently used, in vitro, ex vivo, and in vivo assays to explore the potential of RAAS members to stimulate vascular repair-relevant functions of bone marrow stem/progenitor cells of human and murine origin.
Holliday, Casey M.; Ridgely, Ryan C.; Sedlmayr, Jayc C.; Witmer, Lawrence M.
2010-01-01
Extinct archosaurs, including many non-avian dinosaurs, exhibit relatively simply shaped condylar regions in their appendicular bones, suggesting potentially large amounts of unpreserved epiphyseal (articular) cartilage. This “lost anatomy” is often underappreciated such that the ends of bones are typically considered to be the joint surfaces, potentially having a major impact on functional interpretation. Extant alligators and birds were used to establish an objective basis for inferences about cartilaginous articular structures in such extinct archosaur clades as non-avian dinosaurs. Limb elements of alligators, ostriches, and other birds were dissected, disarticulated, and defleshed. Lengths and condylar shapes of elements with intact epiphyses were measured. Limbs were subsequently completely skeletonized and the measurements repeated. Removal of cartilaginous condylar regions resulted in statistically significant changes in element length and condylar breadth. Moreover, there was marked loss of those cartilaginous structures responsible for joint architecture and congruence. Compared to alligators, birds showed less dramatic, but still significant changes. Condylar morphologies of dinosaur limb bones suggest that most non-coelurosaurian clades possessed large cartilaginous epiphyses that relied on the maintenance of vascular channels that are otherwise eliminated early in ontogeny in smaller-bodied tetrapods. A sensitivity analysis using cartilage correction factors (CCFs) obtained from extant taxa indicates that whereas the presence of cartilaginous epiphyses only moderately increases estimates of dinosaur height and speed, it has important implications for our ability to infer joint morphology, posture, and the complicated functional movements in the limbs of many extinct archosaurs. Evidence suggests that the sizes of sauropod epiphyseal cartilages surpassed those of alligators, which account for at least 10% of hindlimb length. These data suggest that large cartilaginous epiphyses were widely distributed among non-avian archosaurs and must be considered when making inferences about locomotor functional morphology in fossil taxa. PMID:20927347
Transcripts with in silico predicted RNA structure are enriched everywhere in the mouse brain
2012-01-01
Background Post-transcriptional control of gene expression is mostly conducted by specific elements in untranslated regions (UTRs) of mRNAs, in collaboration with specific binding proteins and RNAs. In several well characterized cases, these RNA elements are known to form stable secondary structures. RNA secondary structures also may have major functional implications for long noncoding RNAs (lncRNAs). Recent transcriptional data has indicated the importance of lncRNAs in brain development and function. However, no methodical efforts to investigate this have been undertaken. Here, we aim to systematically analyze the potential for RNA structure in brain-expressed transcripts. Results By comprehensive spatial expression analysis of the adult mouse in situ hybridization data of the Allen Mouse Brain Atlas, we show that transcripts (coding as well as non-coding) associated with in silico predicted structured probes are highly and significantly enriched in almost all analyzed brain regions. Functional implications of these RNA structures and their role in the brain are discussed in detail along with specific examples. We observe that mRNAs with a structure prediction in their UTRs are enriched for binding, transport and localization gene ontology categories. In addition, after manual examination we observe agreement between RNA binding protein interaction sites near the 3’ UTR structures and correlated expression patterns. Conclusions Our results show a potential use for RNA structures in expressed coding as well as noncoding transcripts in the adult mouse brain, and describe the role of structured RNAs in the context of intracellular signaling pathways and regulatory networks. Based on this data we hypothesize that RNA structure is widely involved in transcriptional and translational regulatory mechanisms in the brain and ultimately plays a role in brain function. PMID:22651826
Meier, Timothy B; Lancaster, Melissa A; Mayer, Andrew R; Teague, T Kent; Savitz, Jonathan
2017-02-15
There is a great need to identify potential long-term consequences of contact sport exposure and to identify molecular pathways that may be associated with these changes. We tested the hypothesis that football players with (Ath-mTBI) (n = 25) and without a concussion history (Ath) (n = 24) have altered resting state functional connectivity in regions with previously documented structural changes relative to healthy controls without football or concussion history (HC) (n = 27). As a secondary aim, we tested the hypothesis that group differences in functional connectivity are moderated by the relative ratio of neuroprotective to neurotoxic metabolites of the kynurenine pathway. Ath-mTBI had significantly increased connectivity of motor cortex to the supplementary motor area relative to Ath and HC. In contrast, both Ath-mTBI and Ath had increased connectivity between the left orbital frontal cortex and the right lateral frontal cortex, and between the left cornu ammonis areas 2 and 3/dentate gyrus (CA2-3/DG) of the hippocampus and the middle and posterior cingulate cortices, relative to HC. The relationship between the ratio of plasma concentrations of kynurenic acid to quinolinic acid (KYNA/QUIN) and left pregenual anterior cingulate cortex connectivity to multiple regions as well as KYNA/QUIN and right CA2-3/DG connectivity to multiple regions differed significantly according to football and concussion history. The results suggest that football exposure with and without concussion history can have a significant effect on intrinsic brain connectivity and implicate the kynurenine metabolic pathway as one potential moderator of functional connectivity dependent on football exposure and concussion history.
Holliday, Casey M; Ridgely, Ryan C; Sedlmayr, Jayc C; Witmer, Lawrence M
2010-09-30
Extinct archosaurs, including many non-avian dinosaurs, exhibit relatively simply shaped condylar regions in their appendicular bones, suggesting potentially large amounts of unpreserved epiphyseal (articular) cartilage. This "lost anatomy" is often underappreciated such that the ends of bones are typically considered to be the joint surfaces, potentially having a major impact on functional interpretation. Extant alligators and birds were used to establish an objective basis for inferences about cartilaginous articular structures in such extinct archosaur clades as non-avian dinosaurs. Limb elements of alligators, ostriches, and other birds were dissected, disarticulated, and defleshed. Lengths and condylar shapes of elements with intact epiphyses were measured. Limbs were subsequently completely skeletonized and the measurements repeated. Removal of cartilaginous condylar regions resulted in statistically significant changes in element length and condylar breadth. Moreover, there was marked loss of those cartilaginous structures responsible for joint architecture and congruence. Compared to alligators, birds showed less dramatic, but still significant changes. Condylar morphologies of dinosaur limb bones suggest that most non-coelurosaurian clades possessed large cartilaginous epiphyses that relied on the maintenance of vascular channels that are otherwise eliminated early in ontogeny in smaller-bodied tetrapods. A sensitivity analysis using cartilage correction factors (CCFs) obtained from extant taxa indicates that whereas the presence of cartilaginous epiphyses only moderately increases estimates of dinosaur height and speed, it has important implications for our ability to infer joint morphology, posture, and the complicated functional movements in the limbs of many extinct archosaurs. Evidence suggests that the sizes of sauropod epiphyseal cartilages surpassed those of alligators, which account for at least 10% of hindlimb length. These data suggest that large cartilaginous epiphyses were widely distributed among non-avian archosaurs and must be considered when making inferences about locomotor functional morphology in fossil taxa.
Landscape topography structures the soil microbiome in arctic polygonal tundra
Taş, Neslihan; Prestat, Emmanuel; Wang, Shi; ...
2018-02-22
Global temperature increases are resulting in thaw of permafrost soil in the arctic with increased emission of greenhouse gases (GHGs). Soil microorganisms are responsible for degradation of the trapped organic carbon (C) in permafrost and emission of GHG as it thaws. However, environmental factors governing microbial degradation of soil C and GHG emissions are poorly understood. Here we determined the functional potential of soil microbiomes in arctic tundra across a cryoperturbed polygonal landscape in Barrow, Alaska. Using a combination of metagenome sequencing and gas flux measurements, we found that the soil microbiome composition, diversity and functional potential varied across themore » polygon transect and that specific microbes and functional genes were correlated to GHG measurements. Several draft genomes of novel species were obtained with genes encoding enzymes involved in cycling of complex organic compounds. These results have larger implications for prediction of the influence of the soil microbiome on soil C flux from arctic regions undergoing environmental change.« less
Landscape topography structures the soil microbiome in arctic polygonal tundra
DOE Office of Scientific and Technical Information (OSTI.GOV)
Taş, Neslihan; Prestat, Emmanuel; Wang, Shi
Global temperature increases are resulting in thaw of permafrost soil in the arctic with increased emission of greenhouse gases (GHGs). Soil microorganisms are responsible for degradation of the trapped organic carbon (C) in permafrost and emission of GHG as it thaws. However, environmental factors governing microbial degradation of soil C and GHG emissions are poorly understood. Here we determined the functional potential of soil microbiomes in arctic tundra across a cryoperturbed polygonal landscape in Barrow, Alaska. Using a combination of metagenome sequencing and gas flux measurements, we found that the soil microbiome composition, diversity and functional potential varied across themore » polygon transect and that specific microbes and functional genes were correlated to GHG measurements. Several draft genomes of novel species were obtained with genes encoding enzymes involved in cycling of complex organic compounds. These results have larger implications for prediction of the influence of the soil microbiome on soil C flux from arctic regions undergoing environmental change.« less
Human mast cell and airway smooth muscle cell interactions: implications for asthma.
Page, S; Ammit, A J; Black, J L; Armour, C L
2001-12-01
Asthma is characterized by inflammation, hyperresponsiveness, and remodeling of the airway. Human mast cells (HMCs) play a central role in all of these changes by releasing mediators that cause exaggerated bronchoconstriction, induce human airway smooth muscle (HASM) cell proliferation, and recruit and activate inflammatory cells. Moreover, the number of HMCs present on asthmatic HASM is increased compared with that on nonasthmatic HASM. HASM cells also have the potential to actively participate in the inflammatory process by synthesizing cytokines and chemokines and expressing surface molecules, which have the capacity to perpetuate the inflammatory mechanisms present in asthma. This review specifically examines how the mediators of HMCs have the capacity to modulate many functions of HASM; how the synthetic function of HASM, particularly through the release and expression of stem cell factor, has the potential to influence HMC number and activation in an extraordinarily potent and proinflammatory manner; and how these interactions between HMCs and HASM have potential consequences for airway structure and inflammation relevant to the disease process of asthma.
A human in vitro model of Duchenne muscular dystrophy muscle formation and contractility.
Nesmith, Alexander P; Wagner, Matthew A; Pasqualini, Francesco S; O'Connor, Blakely B; Pincus, Mark J; August, Paul R; Parker, Kevin Kit
2016-10-10
Tongue weakness, like all weakness in Duchenne muscular dystrophy (DMD), occurs as a result of contraction-induced muscle damage and deficient muscular repair. Although membrane fragility is known to potentiate injury in DMD, whether muscle stem cells are implicated in deficient muscular repair remains unclear. We hypothesized that DMD myoblasts are less sensitive to cues in the extracellular matrix designed to potentiate structure-function relationships of healthy muscle. To test this hypothesis, we drew inspiration from the tongue and engineered contractile human muscle tissues on thin films. On this platform, DMD myoblasts formed fewer and smaller myotubes and exhibited impaired polarization of the cell nucleus and contractile cytoskeleton when compared with healthy cells. These structural aberrations were reflected in their functional behavior, as engineered tongues from DMD myoblasts failed to achieve the same contractile strength as healthy tongue structures. These data suggest that dystrophic muscle may fail to organize with respect to extracellular cues necessary to potentiate adaptive growth and remodeling. © 2016 Nesmith et al.
The implications of brain connectivity in the neuropsychology of autism
Maximo, Jose O.; Cadena, Elyse J.; Kana, Rajesh K.
2014-01-01
Autism is a neurodevelopmental disorder that has been associated with atypical brain functioning. Functional connectivity MRI (fcMRI) studies examining neural networks in autism have seen an exponential rise over the last decade. Such investigations have led to characterization of autism as a distributed neural systems disorder. Studies have found widespread cortical underconnectivity, local overconnectivity, and mixed results suggesting disrupted brain connectivity as a potential neural signature of autism. In this review, we summarize the findings of previous fcMRI studies in autism with a detailed examination of their methodology, in order to better understand its potential and to delineate the pitfalls. We also address how a multimodal neuroimaging approach (incorporating different measures of brain connectivity) may help characterize the complex neurobiology of autism at a global level. Finally, we also address the potential of neuroimaging-based markers in assisting neuropsychological assessment of autism. The quest for a biomarker for autism is still ongoing, yet new findings suggest that aberrant brain connectivity may be a promising candidate. PMID:24496901
Quantum dynamics of a plane pendulum
DOE Office of Scientific and Technical Information (OSTI.GOV)
Leibscher, Monika; Schmidt, Burkhard
A semianalytical approach to the quantum dynamics of a plane pendulum is developed, based on Mathieu functions which appear as stationary wave functions. The time-dependent Schroedinger equation is solved for pendular analogs of coherent and squeezed states of a harmonic oscillator, induced by instantaneous changes of the periodic potential energy function. Coherent pendular states are discussed between the harmonic limit for small displacements and the inverted pendulum limit, while squeezed pendular states are shown to interpolate between vibrational and free rotational motion. In the latter case, full and fractional revivals as well as spatiotemporal structures in the time evolution ofmore » the probability densities (quantum carpets) are quantitatively analyzed. Corresponding expressions for the mean orientation are derived in terms of Mathieu functions in time. For periodic double well potentials, different revival schemes, and different quantum carpets are found for the even and odd initial states forming the ground tunneling doublet. Time evolution of the mean alignment allows the separation of states with different parity. Implications for external (rotational) and internal (torsional) motion of molecules induced by intense laser fields are discussed.« less
Adam, Stéphane; Bonsang, Eric; Grotz, Catherine; Perelman, Sergio
2013-01-01
This paper investigates the relationship between the concept of activity (including both professional and nonprofessional) and cognitive functioning among older European individuals. In this research, we used data collected during the first wave of SHARE (Survey on Health, Ageing and Retirement in Europe), and a measurement approach known as stochastic frontier analysis, derived from the economic literature. SHARE includes a large population (n > 25,000) geographically distributed across Europe, and analyzes several dimensions simultaneously, including physical and mental health activity. The main advantages of stochastic frontier analysis are that it allows estimation of parametric function relating cognitive scores and driving factors at the boundary and disentangles frontier noise and distance to frontier components, as well as testing the effect of potential factors on these distances simultaneously. The analysis reveals that all activities are positively related to cognitive functioning in elderly people. Our results are discussed in terms of prevention of cognitive aging and Alzheimer’s disease, and regarding the potential impact that some retirement programs might have on cognitive functioning in individuals across Europe. PMID:23671387
Remsik, Alexander; Young, Brittany; Vermilyea, Rebecca; Kiekoefer, Laura; Abrams, Jessica; Elmore, Samantha Evander; Schultz, Paige; Nair, Veena; Edwards, Dorothy; Williams, Justin; Prabhakaran, Vivek
2016-01-01
Stroke is a leading cause of acquired disability resulting in distal upper extremity functional motor impairment. Stroke mortality rates continue to decline with advances in healthcare and medical technology. This has led to an increased demand for advanced, personalized rehabilitation. Survivors often experience some level of spontaneous recovery shortly after their stroke event; yet reach a functional plateau after which there is exiguous motor recovery. Nevertheless, studies have demonstrated the potential for recovery beyond this plateau. Non-traditional neurorehabilitation techniques, such as those incorporating the brain-computer interface (BCI), are being investigated for rehabilitation. BCIs may offer a gateway to the brain’s plasticity and revolutionize how humans interact with the world. Non-invasive BCIs work by closing the proprioceptive feedback loop with real-time, multi-sensory feedback allowing for volitional modulation of brain signals to assist hand function. BCI technology potentially promotes neuroplasticity and Hebbian-based motor recovery by rewarding cortical activity associated with sensory-motor rhythms through use with a variety of self-guided and assistive modalities. PMID:27112213
Abdelaziz, Rania R; Elkashef, Wagdi F; Said, Eman
2015-07-01
Hepatic encephalopathy is a serious neuropsychiatric disorder usually affecting either acute or chronic hepatic failure patients. Hepatic encephalopathy was replicated in a validated rat model to assess the potential protective efficacy of tranilast against experimentally induced hepatic encephalopathy. Thioacetamide injection significantly impaired hepatic synthetic, metabolic and excretory functions with significant increase in serum NO, IL-6 and IL-13 levels and negative shift in the oxidant/antioxidant balance. Most importantly, there was a significant increase in serum ammonia levels with significant astrocytes' swelling and vacuolization; hallmarks of hepatic encephalopathy. Tranilast administration (300 mg/kg, orally) for 15 days significantly improved hepatic functions, restored oxidant/antioxidant balance, reduced serum NO, IL-6 and IL-13 levels. Meanwhile, serum ammonia significantly declined with significant reduction in astrocytes' swelling and vacuolization. Several mechanisms can be implicated in the observed hepato- and neuroprotective potentials of tranilast, such as its anti-inflammatory potential, its antioxidant potential as well as its immunomodulatory properties. Copyright © 2015 Elsevier B.V. All rights reserved.
2010-01-01
scientific disciplines, who are rapidly pursuing a plethora of exciting and new applications. Concurrently, the implications for potential long-term...focus on the NP toxicity-associated bioeffects that produce acute dose-dependent decreases in viability and alterations in cell function (e.g...t h sufficient contrast and that only high atomic number NPs were readily detectable. More recently, de Jonge et al.25 have unveiled a new STEM
Anne E. Black; Peter Landres
2011-01-01
Current fire policy to restore ecosystem function and resiliency and reduce buildup of hazardous fuels implies a larger future role for fire (both natural and human ignitions) (USDA and USDOI 2000). Yet some fire management (such as building fire line, spike camps, or heli-spots) potentially causes both short- and long-term impacts to forest health. In the short run,...
2000-07-01
receptor 120 16. PRICE CODE 17. SECURITY CLASSIFICATION 18 . SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION 20. LIMITATION OF ABSTRACT OF REPORT OF...THIS PAGE OF ABSTRACT Unclassified Unclassified Unclassified Unlimited NSN 7540-01-280-5500 Standard Form 298 (Rev. 2-89) Prescribed by ANSI Std. Z39- 18 ... 18 -26 Appended Manuscripts 3 INTRODUCTION Recent work in our laboratory has established the importance of a
Structure-activity relationships in beta-defensin peptides.
Taylor, Karen; Barran, Perdita E; Dorin, Julia R
2008-01-01
The beta-defensins comprise a large family of small cationic antimicrobial peptides widely distributed in plants, mammals and insects. These cysteine rich peptides display multifunctional properties with implications as potential therapeutic agents. Recent research has highlighted their role in both the innate and adaptive immune systems as well as being novel melanocortin ligands. Studies investigating structure and function provide an insight into the molecular basis of their immunological properties. (c) 2007 Wiley Periodicals, Inc.
The role of p66Shc deletion in age-associated arterial dysfunction and disease states.
Camici, Giovanni G; Cosentino, Francesco; Tanner, Felix C; Lüscher, Thomas F
2008-11-01
Accumulation of oxidative stress with age is hypothesized to be the primary causative mediator of age-associated diseases. Among different tissues, aging vessels are known to accumulate oxidative damage and undergo functional impairment. Oxidative stress affects the availability and/or balance of key regulators of vascular homeostasis and favors the development of cardiovascular disease. Reactive oxygen species are generated by different intracellular molecular pathways principally located in the cytoplasm and in the mitochondria. The mitochondrial enzyme p66Shc is an adaptor protein and plays an important role as a redox enzyme implicated in mitochondrial reactive oxygen species generation and translation of oxidative signals into apoptosis. Mice lacking p66Shc-/- gene display reduced production of intracellular oxidants and a 30% prolonged life span. For this reasons, a series of studies conceived to elucidate the function of p66Shc and its possible implication in age-associated cardiovascular diseases have been carried out. Indeed, p66Shc-/- mice have been shown to be protected from age-dependent endothelial dysfunction as well as age-related risk factors such as diabetes and hypercholesterolemia. This review focuses on delineating the role of the p66Shc adaptor protein and its potential implication in the pathophysiology of aging and age-related cardiovascular disease.
Molecular Strategies for Targeting Antioxidants to Mitochondria: Therapeutic Implications
2015-01-01
Abstract Mitochondrial function and specifically its implication in cellular redox/oxidative balance is fundamental in controlling the life and death of cells, and has been implicated in a wide range of human pathologies. In this context, mitochondrial therapeutics, particularly those involving mitochondria-targeted antioxidants, have attracted increasing interest as potentially effective therapies for several human diseases. For the past 10 years, great progress has been made in the development and functional testing of molecules that specifically target mitochondria, and there has been special focus on compounds with antioxidant properties. In this review, we will discuss several such strategies, including molecules conjugated with lipophilic cations (e.g., triphenylphosphonium) or rhodamine, conjugates of plant alkaloids, amino-acid- and peptide-based compounds, and liposomes. This area has several major challenges that need to be confronted. Apart from antioxidants and other redox active molecules, current research aims at developing compounds that are capable of modulating other mitochondria-controlled processes, such as apoptosis and autophagy. Multiple chemically different molecular strategies have been developed as delivery tools that offer broad opportunities for mitochondrial manipulation. Additional studies, and particularly in vivo approaches under physiologically relevant conditions, are necessary to confirm the clinical usefulness of these molecules. Antioxid. Redox Signal. 22, 686–729. PMID:25546574
Baskerville, Tracey A; Douglas, Alison J
2010-06-01
Dopamine is an important neuromodulator that exerts widespread effects on the central nervous system (CNS) function. Disruption in dopaminergic neurotransmission can have profound effects on mood and behavior and as such is known to be implicated in various neuropsychiatric behavioral disorders including autism and depression. The subsequent effects on other neurocircuitries due to dysregulated dopamine function have yet to be fully explored. Due to the marked social deficits observed in psychiatric patients, the neuropeptide, oxytocin is emerging as one particular neural substrate that may be influenced by the altered dopamine levels subserving neuropathologic-related behavioral diseases. Oxytocin has a substantial role in social attachment, affiliation and sexual behavior. More recently, it has emerged that disturbances in peripheral and central oxytocin levels have been detected in some patients with dopamine-dependent disorders. Thus, oxytocin is proposed to be a key neural substrate that interacts with central dopamine systems. In addition to psychosocial improvement, oxytocin has recently been implicated in mediating mesolimbic dopamine pathways during drug addiction and withdrawal. This bi-directional role of dopamine has also been implicated during some components of sexual behavior. This review will discuss evidence for the existence dopamine/oxytocin positive interaction in social behavioral paradigms and associated disorders such as sexual dysfunction, autism, addiction, anorexia/bulimia, and depression. Preliminary findings suggest that whilst further rigorous testing has to be conducted to establish a dopamine/oxytocin link in human disorders, animal models seem to indicate the existence of broad and integrated brain circuits where dopamine and oxytocin interactions at least in part mediate socio-affiliative behaviors. A profound disruption to these pathways is likely to underpin associated behavioral disorders. Central oxytocin pathways may serve as a potential therapeutic target to improve mood and socio-affiliative behaviors in patients with profound social deficits and/or drug addiction.
Franz, Jason R; Thelen, Darryl G
2016-06-14
The Achilles tendon (AT) is a complex structure, consisting of distinct fascicle bundles arising from each triceps surae muscle that may act as mechanically independent structures. Advances in tissue imaging are rapidly accelerating our understanding of the complexities of functional Achilles tendon behavior, with potentially important implications for musculoskeletal injury and performance. In this overview of our recent contributions to these efforts, we present the results of complementary experimental and computational approaches to investigate AT behavior during walking and its potential relevance to reduced triceps surae mechanical performance due to aging. Our experimental evidence reveals that older tendons exhibit smaller differences in tissue deformations than young adults between regions of the AT presumed to arise from the gastrocnemius and soleus muscles. These observations are consistent with a reduced capacity for inter-fascicle sliding within the AT, which could have implications for the mechanical independence of the triceps surae muscles. More uniform AT deformations are also correlated with hallmark biomechanical features of elderly gait - namely, a loss of net ankle moment, power, and positive work during push-off. Simulating age-related reductions in the capacity for inter-fascicle sliding in the AT during walking predicts detriments in gastrocnemius muscle-tendon mechanical performance coupled with underlying shifts in fascicle kinematics during push-off. AT compliance, also suspected to vary due to age, systematically modulates those effects. By integrating in vivo imaging with computational modeling, we have gained theoretical insight into multi-scale biomechanical changes due to aging, hypotheses regarding their functional effects, and opportunities for experiments that validate or invalidate these assertions. Copyright © 2016 Elsevier Ltd. All rights reserved.
Little, D C; Newton, R W; Beveridge, M C M
2016-08-01
The status and potential of aquaculture is considered as part of a broader food landscape of wild aquatic and terrestrial food sources. The rationale and resource base required for the development of aquaculture are considered in the context of broader societal development, cultural preferences and human needs. Attention is drawn to the uneven development and current importance of aquaculture globally as well as its considerable heterogeneity of form and function compared with established terrestrial livestock production. The recent drivers of growth in demand and production are examined and the persistent linkages between exploitation of wild stocks, full life cycle culture and the various intermediate forms explored. An emergent trend for sourcing aquaculture feeds from alternatives to marine ingredients is described and the implications for the sector with rapidly growing feed needs discussed. The rise of non-conventional and innovative feed ingredients, often shared with terrestrial livestock, are considered, including aquaculture itself becoming a major source of marine ingredients. The implications for the continued expected growth of aquaculture are set in the context of sustainable intensification, with the challenges that conventional intensification and emergent integration within, and between, value chains explored. The review concludes with a consideration of the implications for dependent livelihoods and projections for various futures based on limited resources but growing demand.
Labrousse-Arias, David; Martínez-Ruiz, Antonio; Calzada, María J
2017-10-20
The extracellular matrix (ECM) is an essential modulator of cell behavior that influences tissue organization. It has a strong relevance in homeostasis and translational implications for human disease. In addition to ECM structural proteins, matricellular proteins are important regulators of the ECM that are involved in a myriad of different pathologies. Recent Advances: Biochemical studies, animal models, and study of human diseases have contributed to the knowledge of molecular mechanisms involved in remodeling of the ECM, both in homeostasis and disease. Some of them might help in the development of new therapeutic strategies. This review aims to review what is known about some of the most studied matricellular proteins and their regulation by hypoxia and redox signaling, as well as the pathological implications of such regulation. Matricellular proteins have complex regulatory functions and are modulated by hypoxia and redox signaling through diverse mechanisms, in some cases with controversial effects that can be cell or tissue specific and context dependent. Therefore, a better understanding of these regulatory processes would be of great benefit and will open new avenues of considerable therapeutic potential. Characterizing the specific molecular mechanisms that modulate matricellular proteins in pathological processes that involve hypoxia and redox signaling warrants additional consideration to harness the potential therapeutic value of these regulatory proteins. Antioxid. Redox Signal. 27, 802-822.
Therapeutic potential of metabotropic glutamate receptor modulators.
Hovelsø, N; Sotty, F; Montezinho, L P; Pinheiro, P S; Herrik, K F; Mørk, A
2012-03-01
Glutamate is the main excitatory neurotransmitter in the central nervous system (CNS) and is a major player in complex brain functions. Glutamatergic transmission is primarily mediated by ionotropic glutamate receptors, which include NMDA, AMPA and kainate receptors. However, glutamate exerts modulatory actions through a family of metabotropic G-protein-coupled glutamate receptors (mGluRs). Dysfunctions of glutamatergic neurotransmission have been implicated in the etiology of several diseases. Therefore, pharmacological modulation of ionotropic glutamate receptors has been widely investigated as a potential therapeutic strategy for the treatment of several disorders associated with glutamatergic dysfunction. However, blockade of ionotropic glutamate receptors might be accompanied by severe side effects due to their vital role in many important physiological functions. A different strategy aimed at pharmacologically interfering with mGluR function has recently gained interest. Many subtype selective agonists and antagonists have been identified and widely used in preclinical studies as an attempt to elucidate the role of specific mGluRs subtypes in glutamatergic transmission. These studies have allowed linkage between specific subtypes and various physiological functions and more importantly to pathological states. This article reviews the currently available knowledge regarding the therapeutic potential of targeting mGluRs in the treatment of several CNS disorders, including schizophrenia, addiction, major depressive disorder and anxiety, Fragile X Syndrome, Parkinson's disease, Alzheimer's disease and pain.
Gromann, Paula M; Tracy, Derek K; Giampietro, Vincent; Brammer, Michael J; Krabbendam, Lydia; Shergill, Sukhwinder S
2012-01-01
Repetitive transcranial magnetic stimulation (rTMS) has been shown to have clinically beneficial effects in altering the perception of auditory hallucinations (AH) in patients with schizophrenia. However, the mode of action is not clear. Recent neuroimaging findings indicate that rTMS has the potential to induce not only local effects but also changes in remote, functionally connected brain regions. Frontotemporal dysconnectivity has been proposed as a mechanism leading to psychotic symptoms in schizophrenia. The current study examines functional connectivity between temporal and frontal brain regions after rTMS and the implications for AH in schizophrenia. A connectivity analysis was conducted on the fMRI data of 11 healthy controls receiving rTMS, compared with 11 matched subjects receiving sham TMS, to the temporoparietal junction, before engaging in a task associated with robust frontotemporal activation. Compared to the control group, the rTMS group showed an altered frontotemporal connectivity with stronger connectivity between the right temporoparietal cortex and the dorsolateral prefrontal cortex and the angular gyrus. This finding provides preliminary evidence for the hypothesis that normalizing the functional connectivity between the temporoparietal and frontal brain regions may underlie the therapeutic effect of rTMS on AH in schizophrenia.
Inhibition of acid sphingomyelinase disrupts LYNUS signaling and triggers autophagy.
Justice, Matthew J; Bronova, Irina; Schweitzer, Kelly S; Poirier, Christophe; Blum, Janice S; Berdyshev, Evgeny V; Petrache, Irina
2018-04-01
Activation of the lysosomal ceramide-producing enzyme, acid sphingomyelinase (ASM), by various stresses is centrally involved in cell death and has been implicated in autophagy. We set out to investigate the role of the baseline ASM activity in maintaining physiological functions of lysosomes, focusing on the lysosomal nutrient-sensing complex (LYNUS), a lysosomal membrane-anchored multiprotein complex that includes mammalian target of rapamycin (mTOR) and transcription factor EB (TFEB). ASM inhibition with imipramine or sphingomyelin phosphodiesterase 1 ( SMPD1 ) siRNA in human lung cells, or by transgenic Smpd1 +/- haploinsufficiency of mouse lungs, markedly reduced mTOR- and P70-S6 kinase (Thr 389)-phosphorylation and modified TFEB in a pattern consistent with its activation. Inhibition of baseline ASM activity significantly increased autophagy with preserved degradative potential. Pulse labeling of sphingolipid metabolites revealed that ASM inhibition markedly decreased sphingosine (Sph) and Sph-1-phosphate (S1P) levels at the level of ceramide hydrolysis. These findings suggest that ASM functions to maintain physiological mTOR signaling and inhibit autophagy and implicate Sph and/or S1P in the control of lysosomal function. Copyright © 2018 by the American Society for Biochemistry and Molecular Biology, Inc.
Engineered BDNF producing cells as a potential treatment for neurologic disease
Deng, Peter; Anderson, Johnathon D.; Yu, Abigail S.; Annett, Geralyn; Fink, Kyle D.; Nolta, Jan A.
2018-01-01
Introduction Brain-derived neurotrophic factor (BDNF) has been implicated in wide range of neurological diseases and injury. This neurotrophic factor is vital for neuronal health, survival, and synaptic connectivity. Many therapies focus on the restoration or enhancement of BDNF following injury or disease progression. Areas covered The present review will focus on the mechanisms in which BDNF exerts its beneficial functioning, current BDNF therapies, issues and potential solutions for delivery of neurotrophic factors to the central nervous system, and other disease indications that may benefit from overexpression or restoration of BDNF. Expert opinion Due to the role of BDNF in neuronal development, maturation, and health, BDNF is implicated in numerous neurological diseases making it a prime therapeutic agent. Numerous studies have shown the therapeutic potential of BDNF in a number of neurodegenerative disease models and in acute CNS injury, however clinical translation has fallen short due to issues in delivering this molecule. The use of MSC as a delivery platform for BDNF holds great promise for clinical advancement of neurotrophic factor restoration. The ease with which MSC can be engineered opens the door to the possibility of using this cell-based delivery system to advance a BDNF therapy to the clinic. PMID:27159050
Test-specific control conditions for functional analyses.
Fahmie, Tara A; Iwata, Brian A; Querim, Angie C; Harper, Jill M
2013-01-01
Most functional analyses of problem behavior include a common condition (play or noncontingent reinforcement) as a control for both positive and negative reinforcement. However, test-specific conditions that control for each potential source of reinforcement may be beneficial occasionally. We compared responding during alone, ignore, play, and differential reinforcement of other behavior (DRO) control conditions for individuals whose problem behavior was maintained by positive or negative reinforcement. Results showed that all of the conditions were effective controls for problem behavior maintained by positive reinforcement; however, the DRO condition was consistently ineffective as a control for problem behavior maintained by negative reinforcement. Implications for the design of functional analyses and future research are discussed. © Society for the Experimental Analysis of Behavior.
Quantum electronic stress: density-functional-theory formulation and physical manifestation.
Hu, Hao; Liu, Miao; Wang, Z F; Zhu, Junyi; Wu, Dangxin; Ding, Hepeng; Liu, Zheng; Liu, Feng
2012-08-03
The concept of quantum electronic stress (QES) is introduced and formulated within density functional theory to elucidate extrinsic electronic effects on the stress state of solids and thin films in the absence of lattice strain. A formal expression of QES (σ(QE)) is derived in relation to deformation potential of electronic states (Ξ) and variation of electron density (Δn), σ(QE) = ΞΔn as a quantum analog of classical Hooke's law. Two distinct QES manifestations are demonstrated quantitatively by density functional theory calculations: (1) in the form of bulk stress induced by charge carriers and (2) in the form of surface stress induced by quantum confinement. Implications of QES in some physical phenomena are discussed to underlie its importance.
Olds, Daniel; Wang, Hsiu -Wen; Page, Katharine L.
2015-09-04
In this work we discuss the potential problems and currently available solutions in modeling powder-diffraction based pair-distribution function (PDF) data from systems where morphological feature information content includes distances in the nanometer length scale, such as finite nanoparticles, nanoporous networks, and nanoscale precipitates in bulk materials. The implications of an experimental finite minimum Q-value are addressed by simulation, which also demonstrates the advantages of combining PDF data with small angle scattering data (SAS). In addition, we introduce a simple Fortran90 code, DShaper, which may be incorporated into PDF data fitting routines in order to approximate the so-called shape-function for anymore » atomistic model.« less
Functional implications of Major Histocompatibility (MH) variation using estuarine fish populations.
Cohen, Sarah; Tirindelli, Joëlle; Gomez-Chiarri, Marta; Nacci, Diane
2006-12-01
Recently, there has been a dramatic expansion of studies of major histocompatibility complex (MHC) variation aimed at discovering functional differences in immunity across wild populations of diverse vertebrate species. Some species with relatively low genetic diversity or under strong directional selection by pathogens have revealed fascinating cases of MHC allelic disease linkage. More generally in genetically diverse species, however, these linkages may be hard to find. In this paper, we review approaches for assessing functional variation in MHC and discuss their potential use for discovering smaller-scale intraspecific spatial and temporal patterns of MHC variation. Then, we describe and illustrate an approach using the structural model to produce a population composite of variation in antigen-binding regions by mapping population-specific substitutions onto functional regions of the molecule. We are producing models of variation in major histocompatibility (MH) loci for populations of non-migratory fish (killifish, Fundulus heteroclitus) resident at sites that vary dramatically in environmental quality. We discuss the goal of relating MH population variation to functional differences in disease susceptibility such as those inferred by observations of parasitic infection and direct measurement of bacterial challenges in the laboratory. Our study has focused on relatively well-studied killifish populations, including those resident in a highly disturbed, chemically contaminated estuary and nearby less contaminated sites. Population-specific genetic changes at MHC antigen-binding loci are described, and evidence relevant to functional implications of these changes is reviewed. Population-specific patterns of variation in antigen-binding regions in combination with a range of assessments of immune function will provide a powerful new approach to reveal functional changes in MHC.
Villamena, Frederick A.
2018-01-01
Impaired mitochondrial function often results in excessive production of reactive oxygen species (ROS) and is involved in the etiology of many chronic diseases, including cardiovascular disease, diabetes, neurodegenerative disorders, and cancer. Moderate levels of mitochondrial ROS, however, can protect against chronic disease by inducing upregulation of mitochondrial capacity and endogenous antioxidant defense. This phenomenon, referred to as mitohormesis, is induced through increased reliance on mitochondrial respiration, which can occur through diet or exercise. Nutritional ketosis is a safe and physiological metabolic state induced through a ketogenic diet low in carbohydrate and moderate in protein. Such a diet increases reliance on mitochondrial respiration and may, therefore, induce mitohormesis. Furthermore, the ketone β-hydroxybutyrate (BHB), which is elevated during nutritional ketosis to levels no greater than those resulting from fasting, acts as a signaling molecule in addition to its traditionally known role as an energy substrate. BHB signaling induces adaptations similar to mitohormesis, thereby expanding the potential benefit of nutritional ketosis beyond carbohydrate restriction. This review describes the evidence supporting enhancement of mitochondrial function and endogenous antioxidant defense in response to nutritional ketosis, as well as the potential mechanisms leading to these adaptations. PMID:29607218
Shimotake, Akihiro; Matsumoto, Riki; Ueno, Taiji; Kunieda, Takeharu; Saito, Satoru; Hoffman, Paul; Kikuchi, Takayuki; Fukuyama, Hidenao; Miyamoto, Susumu; Takahashi, Ryosuke; Ikeda, Akio; Lambon Ralph, Matthew A
2015-10-01
Semantic memory is a crucial higher cortical function that codes the meaning of objects and words, and when impaired after neurological damage, patients are left with significant disability. Investigations of semantic dementia have implicated the anterior temporal lobe (ATL) region, in general, as crucial for multimodal semantic memory. The potentially crucial role of the ventral ATL subregion has been emphasized by recent functional neuroimaging studies, but the necessity of this precise area has not been selectively tested. The implantation of subdural electrode grids over this subregion, for the presurgical assessment of patients with partial epilepsy or brain tumor, offers the dual yet rare opportunities to record cortical local field potentials while participants complete semantic tasks and to stimulate the functionally identified regions in the same participants to evaluate the necessity of these areas in semantic processing. Across 6 patients, and utilizing a variety of semantic assessments, we evaluated and confirmed that the anterior fusiform/inferior temporal gyrus is crucial in multimodal, receptive, and expressive, semantic processing. © The Author 2014. Published by Oxford University Press.
Parrott, Andrew C; Downey, Luke A; Roberts, Carl A; Montgomery, Cathy; Bruno, Raimondo; Fox, Helen C
2017-08-01
The purpose of this article is to debate current understandings about the psychobiological effects of recreational 3,4-methylenedioxymethamphetamine (MDMA or 'ecstasy'), and recommend theoretically-driven topics for future research. Recent empirical findings, especially those from novel topic areas were reviewed. Potential causes for the high variance often found in group findings were also examined. The first empirical reports into psychobiological and psychiatric aspects from the early 1990s concluded that regular users demonstrated some selective psychobiological deficits, for instance worse declarative memory, or heightened depression. More recent research has covered a far wider range of psychobiological functions, and deficits have emerged in aspects of vision, higher cognitive skill, neurohormonal functioning, and foetal developmental outcomes. However, variance levels are often high, indicating that while some recreational users develop problems, others are less affected. Potential reasons for this high variance are debated. An explanatory model based on multi-factorial causation is then proposed. A number of theoretically driven research topics are suggested, in order to empirically investigate the potential causes for these diverse psychobiological deficits. Future neuroimaging studies should study the practical implications of any serotonergic and/or neurohormonal changes, using a wide range of functional measures.
Druggable pockets and binding site centric chemical space: a paradigm shift in drug discovery.
Pérot, Stéphanie; Sperandio, Olivier; Miteva, Maria A; Camproux, Anne-Claude; Villoutreix, Bruno O
2010-08-01
Detection, comparison and analyses of binding pockets are pivotal to structure-based drug design endeavors, from hit identification, screening of exosites and de-orphanization of protein functions to the anticipation of specific and non-specific binding to off- and anti-targets. Here, we analyze protein-ligand complexes and discuss methods that assist binding site identification, prediction of druggability and binding site comparison. The full potential of pockets is yet to be harnessed, and we envision that better understanding of the pocket space will have far-reaching implications in the field of drug discovery, such as the design of pocket-specific compound libraries and scoring functions.
Kang, Chang Moo; Babicky, Michele L.; Lowy, Andrew M.
2014-01-01
Pancreatic cancer remains a devastating disease with a mortality rate that has not changed substantially in decades. Novel therapies are therefore desperately needed. The RON receptor tyrosine kinase has been identified as an important mediator of KRAS oncogene addiction and is over-expressed in the majority of pancreatic cancers. Preclinical studies that inhibition of RON function decrease pancreatic cancer cell migration, invasion and survival and can sensitize pancreatic cancer cells to chemotherapy. This article reviews the current state of knowledge regarding RON biology and pancreatic cancer and discusses its potential as a therapeutic target. PMID:24518495
Civil Uses of Remotely Piloted Aircraft
NASA Technical Reports Server (NTRS)
Aderhold, J. R.; Gordon, G.; Scott, G. W.
1976-01-01
The economic, technical, and environmental implications of remotely piloted vehicles (RVP) are examined. The time frame is 1980-85. Representative uses are selected; detailed functional and performance requirements are derived for RPV systems; and conceptual system designs are devised. Total system cost comparisons are made with non-RPV alternatives. The potential market demand for RPV systems is estimated. Environmental and safety requirements are examined, and legal and regulatory concerns are identified. A potential demand for 2,000-11,000 RVP systems is estimated. Typical cost savings of 25 to 35% compared to non-RPV alternatives are determined. There appear to be no environmental problems, and the safety issue appears manageable.
Renal Denervation to Modify Hypertension and the Heart Failure State.
Zhong, Ming; Kim, Luke K; Swaminathan, Rajesh V; Feldman, Dmitriy N
2017-07-01
Sympathetic overactivation of renal afferent and efferent nerves have been implicated in the development and maintenance of several cardiovascular disease states, including resistant hypertension and heart failure with both reduced and preserved systolic function. With the development of minimally invasive catheter-based techniques, percutaneous renal denervation has become a safe and effective method of attenuating sympathetic overactivation. Percutaneous renal denervation, therefore, has the potential to modify and treat hypertension and congestive heart failure. Although future randomized controlled studies are needed to definitively prove its efficacy, renal denervation has the potential to change the way we view and treat cardiovascular disease. Copyright © 2017 Elsevier Inc. All rights reserved.
Gorain, Bapi; Choudhury, Hira; Pandey, Manisha; Kesharwani, Prashant; Abeer, Muhammad Mustafa; Tekade, Rakesh Kumar; Hussain, Zahid
2018-08-01
Myocardial infarction (cardiac tissue death) is among the most prevalent causes of death among the cardiac patients due to the inability of self-repair in cardiac tissues. Myocardial tissue engineering is regarded as one of the most realistic strategies for repairing damaged cardiac tissue. However, hindrance in transduction of electric signals across the cardiomyocytes due to insulating properties of polymeric materials worsens the clinical viability of myocardial tissue engineering. Aligned and conductive scaffolds based on Carbon nanotubes (CNT) have gained remarkable recognition due to their exceptional attributes which provide synthetic but viable microenvironment for regeneration of engineered cardiomyocytes. This review presents an overview and critical analysis of pharmaceutical implications and therapeutic feasibility of CNT based scaffolds in improving the cardiac tissue regeneration and functionality. The expository analysis of the available evidence revealed that inclusion of single- or multi-walled CNT into fibrous, polymeric, and elastomeric scaffolds results in significant improvement in electrical stimulation and signal transduction through cardiomyocytes. Moreover, incorporation of CNT in engineering scaffolds showed a greater potential of augmenting cardiomyocyte proliferation, differentiation, and maturation and has improved synchronous beating of cardiomyocytes. Despite promising ability of CNT in promoting functionality of cardiomyocytes, their presence in scaffolds resulted in substantial improvement in mechanical properties and structural integrity. Conclusively, this review provides new insight into the remarkable potential of CNT aligned scaffolds in improving the functionality of engineered cardiac tissue and signifies their feasibility in cardiac tissue regenerative medicines and stem cell therapy. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
Altered prefrontal correlates of monetary anticipation and outcome in chronic pain.
Martucci, Katherine T; Borg, Nicholas; MacNiven, Kelly H; Knutson, Brian; Mackey, Sean C
2018-04-04
Chronic pain may alter both affect- and value-related behaviors, which represents a potentially treatable aspect of chronic pain experience. Current understanding of how chronic pain influences the function of brain reward systems, however, is limited. Using a monetary incentive delay task and functional magnetic resonance imaging (fMRI), we measured neural correlates of reward anticipation and outcomes in female participants with the chronic pain condition of fibromyalgia (N = 17) and age-matched, pain-free, female controls (N = 15). We hypothesized that patients would demonstrate lower positive arousal, as well as altered reward anticipation and outcome activity within corticostriatal circuits implicated in reward processing. Patients demonstrated lower arousal ratings as compared with controls, but no group differences were observed for valence, positive arousal, or negative arousal ratings. Group fMRI analyses were conducted to determine predetermined region of interest, nucleus accumbens (NAcc) and medial prefrontal cortex (mPFC), responses to potential gains, potential losses, reward outcomes, and punishment outcomes. Compared with controls, patients demonstrated similar, although slightly reduced, NAcc activity during gain anticipation. Conversely, patients demonstrated dramatically reduced mPFC activity during gain anticipation-possibly related to lower estimated reward probabilities. Further, patients demonstrated normal mPFC activity to reward outcomes, but dramatically heightened mPFC activity to no-loss (nonpunishment) outcomes. In parallel to NAcc and mPFC responses, patients demonstrated slightly reduced activity during reward anticipation in other brain regions, which included the ventral tegmental area, anterior cingulate cortex, and anterior insular cortex. Together, these results implicate altered corticostriatal processing of monetary rewards in chronic pain.
Implications of dual practice for universal health coverage.
McPake, Barbara; Russo, Giuliano; Hipgrave, David; Hort, Krishna; Campbell, James
2016-02-01
Making progress towards universal health coverage (UHC) requires that health workers are adequate in numbers, prepared for their jobs and motivated to perform. In establishing the best ways to develop the health workforce, relatively little attention has been paid to the trends and implications of dual practice - concurrent employment in public and private sectors. We review recent research on dual practice for its potential to guide staffing policies in relation to UHC. Many studies describe the characteristics and correlates of dual practice and speculate about impacts, but there is very little evidence that is directly relevant to policy-makers. No studies have evaluated the impact of policies on the characteristics of dual practice or implications for UHC. We address this lack and call for case studies of policy interventions on dual practice in different contexts. Such research requires investment in better data collection and greater determination on the part of researchers, research funding bodies and national research councils to overcome the difficulties of researching sensitive topics of health systems functions.
RNAi and retroviruses: are they in RISC?
Vasselon, Thierry; Bouttier, Manuella; Saumet, Anne; Lecellier, Charles-Henri
2013-02-01
RNA interference (RNAi) is a potent cellular system against viruses in various organisms. Although common traits are observed in plants, insects, and nematodes, the situation observed in mammals appears more complex. In mammalian somatic cells, RNAi is implicated in endonucleolytic cleavage mediated by artificially delivered small interfering RNAs (siRNAs) as well as in translation repression mediated by microRNAs (miRNAs). Because siRNAs and miRNAs recognize viral mRNAs, RNAi inherently limits virus production and participates in antiviral defense. However, several observations made in the cases of hepatitis C virus and retroviruses (including the human immunodeficiency virus and the primate foamy virus) bring evidence that this relationship is much more complex and that certain components of the RNAi effector complex [called the RNA-induced silencing complex (RISC)], such as AGO2, are also required for viral replication. Here, we summarize recent discoveries that have revealed this dual implication in virus biology. We further discuss their potential implications for the functions of RNAi-related proteins, with special emphasis on retrotransposition and genome stability.
Neuroplasticity and functional recovery in multiple sclerosis
Tomassini, Valentina; Matthews, Paul M.; Thompson, Alan J.; Fuglø, Daniel; Geurts, Jeroen J.; Johansen-Berg, Heidi; Jones, Derek K.; Rocca, Maria A.; Wise, Richard G.; Barkhof, Frederik; Palace, Jacqueline
2013-01-01
The development of therapeutic strategies that promote functional recovery is a major goal of multiple sclerosis (MS) research. Neuroscientific and methodological advances have improved our understanding of the brain’s recovery from damage, generating novel hypotheses for potential targets or modes of intervention and laying the foundation for the development of scientifically informed strategies promoting recovery in interventional studies. This Review aims to encourage the transition from characterization of recovery mechanisms to the development of strategies that promote recovery in MS. We discuss current evidence for functional reorganization that underlies recovery and its implications for development of new recovery-oriented strategies in MS. Promotion of functional recovery requires an improved understanding of recovery mechanisms modulated by interventions and the development of reliable measures of therapeutic effects. As imaging methods can be used to measure functional and structural alterations associated with recovery, this Review discusses their use as reliable markers to measure the effects of interventions. PMID:22986429
Giant mitochondria do not fuse and exchange their contents with normal mitochondria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Navratil, Marian; Terman, Alexei; Arriaga, Edgar A.
2008-01-01
Giant mitochondria accumulate within aged or diseased postmitotic cells as a consequence of insufficient autophagy, which is normally responsible for mitochondrial degradation. We report that giant mitochondria accumulating in cultured rat myoblasts due to inhibition of autophagy have low inner membrane potential and do not fuse with each other or with normal mitochondria. In addition to the low inner mitochondrial membrane potential in giant mitochondria, the quantity of the OPA1 mitochondrial fusion protein in these mitochondria was low, but the abundance of mitofusin-2 (Mfn2) remained unchanged. The combination of these factors may explain the lack of mitochondrial fusion in giantmore » mitochondria and imply that the dysfunctional giant mitochondria cannot restore their function by fusing and exchanging their contents with fully functional mitochondria. These findings have important implications for understanding the mechanisms of accumulation of age-related mitochondrial damage in postmitotic cells.« less
Pharmacologic overview of Withania somnifera, the Indian Ginseng.
Dar, Nawab John; Hamid, Abid; Ahmad, Muzamil
2015-12-01
Withania somnifera, also called 'Indian ginseng', is an important medicinal plant of the Indian subcontinent. It is widely used, singly or in combination, with other herbs against many ailments in Indian Systems of Medicine since time immemorial. Withania somnifera contains a spectrum of diverse phytochemicals enabling it to have a broad range of biological implications. In preclinical studies, it has shown anti-microbial, anti-inflammatory, anti-tumor, anti-stress, neuroprotective, cardioprotective, and anti-diabetic properties. Additionally, it has demonstrated the ability to reduce reactive oxygen species, modulate mitochondrial function, regulate apoptosis, and reduce inflammation and enhance endothelial function. In view of these pharmacologic properties, W. somnifera is a potential drug candidate to treat various clinical conditions, particularly related to the nervous system. In this review, we summarize the pharmacologic characteristics and discuss the mechanisms of action and potential therapeutic applications of the plant and its active constituents.
Urrios, Arturo; de Nadal, Eulàlia; Solé, Ricard; Posas, Francesc
2016-01-01
Engineered synthetic biological devices have been designed to perform a variety of functions from sensing molecules and bioremediation to energy production and biomedicine. Notwithstanding, a major limitation of in vivo circuit implementation is the constraint associated to the use of standard methodologies for circuit design. Thus, future success of these devices depends on obtaining circuits with scalable complexity and reusable parts. Here we show how to build complex computational devices using multicellular consortia and space as key computational elements. This spatial modular design grants scalability since its general architecture is independent of the circuit’s complexity, minimizes wiring requirements and allows component reusability with minimal genetic engineering. The potential use of this approach is demonstrated by implementation of complex logical functions with up to six inputs, thus demonstrating the scalability and flexibility of this method. The potential implications of our results are outlined. PMID:26829588
Gong, Shi-qiang; Niu, Li-na; Kemp, Lisa K.; Yiu, Cynthia K.Y.; Ryou, Heonjune; Qi, Yi-pin; Blizzard, John D.; Nikonov, Sergey; Brackett, Martha G.; Messer, Regina L.W.; Wu, Christine D.; Mao, Jing; Brister, L. Bryan; Rueggeberg, Frederick A.; Arola, Dwayne D.; Pashley, David H.; Tay, Franklin R.
2012-01-01
Design of antimicrobial polymers for enhancing healthcare issues and minimizing environmental problems is an important endeavor with both fundamental and practical implications. Quaternary ammonium silane-functionalized methacrylate (QAMS) represents an example of antimicrobial macromonomers synthesized by a sol-gel chemical route; these compounds possess flexible Si-O-Si bonds. In present work, a partially-hydrolyzed QAMS copolymerized with bis-GMA is introduced. This methacrylate resin was shown to possess desirable mechanical properties with both a high degree of conversion and minimal polymerization shrinkage. Kill-on-contact microbiocidal activities of this resin were demonstrated using single-species biofilms of Streptococcus mutans (ATCC 36558), Actinomyces naeslundii (ATCC 12104) and Candida albicans (ATCC 90028). Improved mechanical properties after hydration provided the proof-of-concept that QAMS-incorporated resin exhibits self-repair potential via water-induced condensation of organic modified silicate (ormosil) phases within the polymerized resin matrix. PMID:22659173
Somasuntharam, Inthirai; Yehl, Kevin; Carroll, Sheridan L.; Maxwell, Joshua T.; Martinez, Mario D.; Che, Pao-Lin; Brown, Milton E.; Salaita, Khalid; Davis, Michael E.
2017-01-01
In this study, we used deoxyribozyme (DNAzyme) functionalized gold nanoparticles (AuNPs) to catalytically silence tumor necrosis factor-α (TNF-α) in vivo as a potential therapeutic for myocardial infarction (MI). Using primary macrophages as a model, we demonstrated 50% knockdown of TNF-α, which was not attainable using Lipofectamine-based approaches. Local injection of DNAzyme conjugated to gold particles (AuNPs) in the rat myocardium yielded TNF-α knockdown efficiencies of 50%, which resulted in significant anti-inflammatory effects and improvement in acute cardiac function following MI. Our results represent the first example showing the use of DNAzyme AuNP conjugates in vivo for viable delivery and gene regulation. This is significant as TNF-α is a multibillion dollar drug target implicated in many inflammatory-mediated disorders, thus underscoring the potential impact of DNAzyme-conjugated AuNPs. PMID:26773660
The fate of paternal mitochondria in marmoset pre-implantation embryos.
Luetjens, C M; Wesselmann, R
2008-06-01
Sperm-derived mitochondria are integrated into the oocyte at fertilization but seem to vanish during the early cleavage phase. The developmental potential of pre-implantation embryos seems to be closely related to their ability to induce degeneration of these mitochondria, but the mechanisms underlying their loss of function are not yet understood. This study focuses on the fate of paternal mitochondria in pre-implantation embryos. Stimulation, collection and in vitro culture of oocytes from Callithrix jacchus, allows the study of the destiny of paternal mitochondria by utilizing immunostaining of pre-implantation embryos, fluorescence and laserscanning microscopy. Live pre-implantation embryos were stained with a fluorescence indicator reflecting mitochondrial membrane potential. Evidence indicating the loss of mitochondrial function was not found nor that apoptosis pathways were involved in the disappearance of paternally derived mitochondria. These findings may have implications for mitochondrially inherited diseases and could lead to new strategies for improving assisted reproduction.
Physiological and ecological implications of ocean deoxygenation for vision in marine organisms.
McCormick, Lillian R; Levin, Lisa A
2017-09-13
Climate change has induced ocean deoxygenation and exacerbated eutrophication-driven hypoxia in recent decades, affecting the physiology, behaviour and ecology of marine organisms. The high oxygen demand of visual tissues and the known inhibitory effects of hypoxia on human vision raise the questions if and how ocean deoxygenation alters vision in marine organisms. This is particularly important given the rapid loss of oxygen and strong vertical gradients in oxygen concentration in many areas of the ocean. This review evaluates the potential effects of low oxygen (hypoxia) on visual function in marine animals and their implications for marine biota under current and future ocean deoxygenation based on evidence from terrestrial and a few marine organisms. Evolutionary history shows radiation of eye designs during a period of increasing ocean oxygenation. Physiological effects of hypoxia on photoreceptor function and light sensitivity, in combination with morphological changes that may occur throughout ontogeny, have the potential to alter visual behaviour and, subsequently, the ecology of marine organisms, particularly for fish, cephalopods and arthropods with 'fast' vision. Visual responses to hypoxia, including greater light requirements, offer an alternative hypothesis for observed habitat compression and shoaling vertical distributions in visual marine species subject to ocean deoxygenation, which merits further investigation.This article is part of the themed issue 'Ocean ventilation and deoxygenation in a warming world'. © 2017 The Author(s).
Neuregulin in Cardiovascular Development and Disease
Odiete, Oghenerukevwe; Hill, Michael F.; Sawyer, Douglas B.
2013-01-01
Studies in genetically modified mice have demonstrated that neuregulin-1 (NRG-1), along with the erythroblastic leukemia viral oncogene homolog (ErbB) 2, 3, and 4 receptor tyrosine kinases, is necessary for multiple aspects of cardiovascular development. These observations stimulated in vitro and in vivo animal studies, implicating NRG-1/ErbB signaling in the regulation of cardiac cell biology throughout life. Cardiovascular effects of ErbB2-targeted cancer therapies provide evidence in humans that ErbB signaling plays a role in the maintenance of cardiac function. These and other studies suggest a conceptual model in which a key function of NRG-1/ErbB signaling is to mediate adaptations of the heart to physiological and pathological stimuli through activation of intracellular kinase cascades that regulate tissue plasticity. Recent work implicates NRG-1/ErbB signaling in the regulation of multiple aspects of cardiovascular biology, including angiogenesis, blood pressure, and skeletal muscle responses to exercise. The therapeutic potential of recombinant NRG-1 as a potential treatment for heart failure has been demonstrated in animal models and is now being explored in clinical studies. NRG-1 is found in human serum and plasma, and it correlates with some clinical parameters, suggesting that it may have value as an indicator of prognosis. In this review, we bring together this growing literature on NRG-1 and its significance in cardiovascular development and disease. PMID:23104879
Voon, Valerie; Droux, Fabien; Morris, Laurel; Chabardes, Stephan; Bougerol, Thierry; David, Olivier; Krack, Paul; Polosan, Mircea
2017-01-01
Abstract Why do we make hasty decisions for short-term gain? Rapid decision-making with limited accumulation of evidence and delay discounting are forms of decisional impulsivity. The subthalamic nucleus is implicated in inhibitory function but its role in decisional impulsivity is less well-understood. Here we assess decisional impulsivity in subjects with obsessive compulsive disorder who have undergone deep brain stimulation of the limbic and associative subthalamic nucleus. We show that stimulation of the subthalamic nucleus is causally implicated in increasing decisional impulsivity with less accumulation of evidence during probabilistic uncertainty and in enhancing delay discounting. Subthalamic stimulation shifts evidence accumulation in subjects with obsessive-compulsive disorder towards a functional less cautious style closer to that of healthy controls emphasizing its adaptive nature. Thus, subjects with obsessive compulsive disorder on subthalamic stimulation may be less likely to check for evidence (e.g. checking that the stove is on) with no difference in subjective confidence (or doubt). In a separate study, we replicate in humans (154 healthy controls) using resting state functional connectivity, tracing studies conducted in non-human primates dissociating limbic, associative and motor frontal hyper-direct connectivity with anterior and posterior subregions of the subthalamic nucleus. We show lateralization of functional connectivity of bilateral ventral striatum to right anterior ventromedial subthalamic nucleus consistent with previous observations of lateralization of emotionally evoked activity to right ventral subthalamic nucleus. We use a multi-echo sequence with independent components analysis, which has been shown to have enhanced signal-to-noise ratio, thus optimizing visualization of small subcortical structures. These findings in healthy controls converge with the effective contacts in obsessive compulsive disorder patients localized within the anterior and ventral subthalamic nucleus. We further show that evidence accumulation is associated with anterior associative-limbic subthalamic nucleus and right dorsolateral prefrontal functional connectivity in healthy controls, a region implicated in decision-making under uncertainty. Together, our findings highlight specificity of the anterior associative-limbic subthalamic nucleus in decisional impulsivity. Given increasing interest in the potential for subthalamic stimulation in psychiatric disorders and the neuropsychiatric symptoms of Parkinson’s disease, these findings have clinical implications for behavioural symptoms and cognitive effects as a function of localization of subthalamic stimulation. PMID:28040671
Voon, Valerie; Droux, Fabien; Morris, Laurel; Chabardes, Stephan; Bougerol, Thierry; David, Olivier; Krack, Paul; Polosan, Mircea
2017-02-01
Why do we make hasty decisions for short-term gain? Rapid decision-making with limited accumulation of evidence and delay discounting are forms of decisional impulsivity. The subthalamic nucleus is implicated in inhibitory function but its role in decisional impulsivity is less well-understood. Here we assess decisional impulsivity in subjects with obsessive compulsive disorder who have undergone deep brain stimulation of the limbic and associative subthalamic nucleus. We show that stimulation of the subthalamic nucleus is causally implicated in increasing decisional impulsivity with less accumulation of evidence during probabilistic uncertainty and in enhancing delay discounting. Subthalamic stimulation shifts evidence accumulation in subjects with obsessive-compulsive disorder towards a functional less cautious style closer to that of healthy controls emphasizing its adaptive nature. Thus, subjects with obsessive compulsive disorder on subthalamic stimulation may be less likely to check for evidence (e.g. checking that the stove is on) with no difference in subjective confidence (or doubt). In a separate study, we replicate in humans (154 healthy controls) using resting state functional connectivity, tracing studies conducted in non-human primates dissociating limbic, associative and motor frontal hyper-direct connectivity with anterior and posterior subregions of the subthalamic nucleus. We show lateralization of functional connectivity of bilateral ventral striatum to right anterior ventromedial subthalamic nucleus consistent with previous observations of lateralization of emotionally evoked activity to right ventral subthalamic nucleus. We use a multi-echo sequence with independent components analysis, which has been shown to have enhanced signal-to-noise ratio, thus optimizing visualization of small subcortical structures. These findings in healthy controls converge with the effective contacts in obsessive compulsive disorder patients localized within the anterior and ventral subthalamic nucleus. We further show that evidence accumulation is associated with anterior associative-limbic subthalamic nucleus and right dorsolateral prefrontal functional connectivity in healthy controls, a region implicated in decision-making under uncertainty. Together, our findings highlight specificity of the anterior associative-limbic subthalamic nucleus in decisional impulsivity. Given increasing interest in the potential for subthalamic stimulation in psychiatric disorders and the neuropsychiatric symptoms of Parkinson's disease, these findings have clinical implications for behavioural symptoms and cognitive effects as a function of localization of subthalamic stimulation. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain.
Dantas, Joana M.; Morgado, Leonor; Aklujkar, Muktak; ...
2015-07-30
Multiheme cytochromes have been implicated in Geobacter sulfurreducens extracellular electron transfer (EET). These proteins are potential targets to improve EET and enhance bioremediation and electrical current production by G. sulfurreducens. However, the functional characterization of multiheme cytochromes is particularly complex due to the co-existence of several microstates in solution, connecting the fully reduced and fully oxidized states. Throughout the last decade, new strategies have been developed to characterize multiheme redox proteins functionally and structurally. These strategies were used to reveal the functional mechanism of G. sulfurreducens multiheme cytochromes and also to identify key residues in these proteins for EET. Inmore » previous studies, we set the foundations for enhancement of the EET abilities of G. sulfurreducens by characterizing a family of five triheme cytochromes (PpcA-E). These periplasmic cytochromes are implicated in electron transfer between the oxidative reactions of metabolism in the cytoplasm and the reduction of extracellular terminal electron acceptors at the cell's outer surface. The results obtained suggested that PpcA can couple e -/H + transfer, a property that might contribute to the proton electrochemical gradient across the cytoplasmic membrane for metabolic energy production. The structural and functional properties of PpcA were characterized in detail and used for rational design of a family of 23 single site PpcA mutants. In this review, we summarize the functional characterization of the native and mutant proteins. Mutants that retain the mechanistic features of PpcA and adopt preferential e -/H + transfer pathways at lower reduction potential values compared to the wild-type protein were selected for in vivo studies as the best candidates to increase the electron transfer rate of G. sulfurreducens. For the first time G. sulfurreducens strains have been manipulated by the introduction of mutant forms of essential proteins with the aim to develop and improve bioelectrochemical technologies.« less
The Relationship between Mathematical Induction, Proposition Functions, and Implication Functions
ERIC Educational Resources Information Center
Andrew, Lane
2010-01-01
In this study, I explored the relationship between mathematical induction ability and proposition and implication functions through a mixed methods approach. Students from three universities (N = 78) and 6 classrooms completed a written assessment testing their conceptual and procedural capabilities with induction and functions. In addition, I…
Linking plant functional trait plasticity and the large increase in forest water use efficiency
NASA Astrophysics Data System (ADS)
Mastrotheodoros, Theodoros; Pappas, Christoforos; Molnar, Peter; Burlando, Paolo; Keenan, Trevor F.; Gentine, Pierre; Gough, Christopher M.; Fatichi, Simone
2017-09-01
Elevated atmospheric CO2 concentrations are expected to enhance photosynthesis and reduce stomatal conductance, thus increasing plant water use efficiency. A recent study based on eddy covariance flux observations from Northern Hemisphere forests showed a large increase in inherent water use efficiency (IWUE). Here we used an updated version of the same data set and robust uncertainty quantification to revisit these contemporary IWUE trends. We tested the hypothesis that the observed IWUE increase could be attributed to interannual trends in plant functional traits, potentially triggered by environmental change. We found that IWUE increased by 1.3% yr-1, which is less than previously reported but still larger than theoretical expectations. Numerical simulations with the Tethys-Chloris ecosystem model using temporally static plant functional traits cannot explain this increase. Simulations with plant functional trait plasticity, i.e., temporal changes in model parameters such as specific leaf area and maximum Rubisco capacity, match the observed trends in IWUE. Our results show that trends in plant functional traits, equal to 1.0% yr-1, can explain the observed IWUE trends. Thus, at decadal or longer time scales, trait plasticity could potentially influence forest water, carbon, and energy fluxes with profound implications for both the monitoring of temporal changes in plant functional traits and their representation in Earth system models.
O’Callaghan, Maureen; Condron, Leo M.; Kowalchuk, George A.; Van Nostrand, Joy D.; Zhou, Jizhong; Wakelin, Steven A.
2018-01-01
Cropping soils vary in extent of natural suppression of soil-borne plant diseases. However, it is unknown whether similar variation occurs across pastoral agricultural systems. We examined soil microbial community properties known to be associated with disease suppression across 50 pastoral fields varying in management intensity. The composition and abundance of the disease-suppressive community were assessed from both taxonomic and functional perspectives. Pseudomonas bacteria were selected as a general taxonomic indicator of disease suppressive potential, while genes associated with the biosynthesis of a suite of secondary metabolites provided functional markers (GeoChip 5.0 microarray analysis). The composition of both the Pseudomonas communities and disease suppressive functional genes were responsive to land use. Underlying soil properties explained 37% of the variation in Pseudomonas community structure and up to 61% of the variation in the abundance of disease suppressive functional genes. Notably, measures of soil organic matter quality, C:P ratio, and aromaticity of the dissolved organic matter content (carbon recalcitrance), influenced both the taxonomic and functional disease suppressive potential of the pasture soils. Our results suggest that key components of the soil microbial community may be managed on-farm to enhance disease suppression and plant productivity. PMID:29734390
Dignam, Bryony E A; O'Callaghan, Maureen; Condron, Leo M; Kowalchuk, George A; Van Nostrand, Joy D; Zhou, Jizhong; Wakelin, Steven A
2018-01-01
Cropping soils vary in extent of natural suppression of soil-borne plant diseases. However, it is unknown whether similar variation occurs across pastoral agricultural systems. We examined soil microbial community properties known to be associated with disease suppression across 50 pastoral fields varying in management intensity. The composition and abundance of the disease-suppressive community were assessed from both taxonomic and functional perspectives. Pseudomonas bacteria were selected as a general taxonomic indicator of disease suppressive potential, while genes associated with the biosynthesis of a suite of secondary metabolites provided functional markers (GeoChip 5.0 microarray analysis). The composition of both the Pseudomonas communities and disease suppressive functional genes were responsive to land use. Underlying soil properties explained 37% of the variation in Pseudomonas community structure and up to 61% of the variation in the abundance of disease suppressive functional genes. Notably, measures of soil organic matter quality, C:P ratio, and aromaticity of the dissolved organic matter content (carbon recalcitrance), influenced both the taxonomic and functional disease suppressive potential of the pasture soils. Our results suggest that key components of the soil microbial community may be managed on-farm to enhance disease suppression and plant productivity.
Krystal, John H; Anticevic, Alan; Yang, Genevieve J; Dragoi, George; Driesen, Naomi R; Wang, Xiao-Jing; Murray, John D
2017-05-15
The functional optimization of neural ensembles is central to human higher cognitive functions. When the functions through which neural activity is tuned fail to develop or break down, symptoms and cognitive impairments arise. This review considers ways in which disturbances in the balance of excitation and inhibition might develop and be expressed in cortical networks in association with schizophrenia. This presentation is framed within a developmental perspective that begins with disturbances in glutamate synaptic development in utero. It considers developmental correlates and consequences, including compensatory mechanisms that increase intrinsic excitability or reduce inhibitory tone. It also considers the possibility that these homeostatic increases in excitability have potential negative functional and structural consequences. These negative functional consequences of disinhibition may include reduced working memory-related cortical activity associated with the downslope of the "inverted-U" input-output curve, impaired spatial tuning of neural activity and impaired sparse coding of information, and deficits in the temporal tuning of neural activity and its implication for neural codes. The review concludes by considering the functional significance of noisy activity for neural network function. The presentation draws on computational neuroscience and pharmacologic and genetic studies in animals and humans, particularly those involving N-methyl-D-aspartate glutamate receptor antagonists, to illustrate principles of network regulation that give rise to features of neural dysfunction associated with schizophrenia. While this presentation focuses on schizophrenia, the general principles outlined in the review may have broad implications for considering disturbances in the regulation of neural ensembles in psychiatric disorders. Published by Elsevier Inc.
Biological invasions as disruptors of plant reproductive mutualisms.
Traveset, Anna; Richardson, David M
2006-04-01
Invasive alien species affect the composition and functioning of invaded ecosystems in many ways, altering ecological interactions that have arisen over evolutionary timescales. Specifically, disruptions to pollination and seed-dispersal mutualistic interactions are often documented, although the profound implications of such impacts are not widely recognized. Such disruptions can occur via the introduction of alien pollinators, seed dispersers, herbivores, predators or plants, and we define here the many potential outcomes of each situation. The frequency and circumstances under which each category of mechanisms operates are also poorly known. Most evidence is from population-level studies, and the implications for global biodiversity are difficult to predict. Further insights are needed on the degree of resilience in interaction networks, but the preliminary picture suggests that invasive species frequently cause profound disruptions to plant reproductive mutualisms.
What can flies tell us about copper homeostasis?
Southon, Adam; Burke, Richard; Camakaris, James
2013-10-01
Copper (Cu) is an essential redox active metal that is potentially toxic in excess. Multicellular organisms acquire Cu from the diet and must regulate uptake, storage, distribution and export of Cu at both the cellular and organismal levels. Systemic Cu deficiency can be fatal, as seen in Menkes disease patients. Conversely Cu toxicity occurs in patients with Wilson disease. Cu dyshomeostasis has also been implicated in neurodegenerative disorders such as Alzheimer's disease. Over the last decade, the fly Drosophila melanogaster has become an important model organism for the elucidation of eukaryotic Cu regulatory mechanisms. Gene discovery approaches with Drosophila have identified novel genes with conserved protein functions relevant to Cu homeostasis in humans. This review focuses on our current understanding of Cu uptake, distribution and export in Drosophila and the implications for mammals.
A Noncoding, Regulatory Mutation Implicates HCFC1 in Nonsyndromic Intellectual Disability
Huang, Lingli; Jolly, Lachlan A.; Willis-Owen, Saffron; Gardner, Alison; Kumar, Raman; Douglas, Evelyn; Shoubridge, Cheryl; Wieczorek, Dagmar; Tzschach, Andreas; Cohen, Monika; Hackett, Anna; Field, Michael; Froyen, Guy; Hu, Hao; Haas, Stefan A.; Ropers, Hans-Hilger; Kalscheuer, Vera M.; Corbett, Mark A.; Gecz, Jozef
2012-01-01
The discovery of mutations causing human disease has so far been biased toward protein-coding regions. Having excluded all annotated coding regions, we performed targeted massively parallel resequencing of the nonrepetitive genomic linkage interval at Xq28 of family MRX3. We identified in the binding site of transcription factor YY1 a regulatory mutation that leads to overexpression of the chromatin-associated transcriptional regulator HCFC1. When tested on embryonic murine neural stem cells and embryonic hippocampal neurons, HCFC1 overexpression led to a significant increase of the production of astrocytes and a considerable reduction in neurite growth. Two other nonsynonymous, potentially deleterious changes have been identified by X-exome sequencing in individuals with intellectual disability, implicating HCFC1 in normal brain function. PMID:23000143
Inhibitors of Protein Methyltransferases and Demethylases
2017-01-01
Post-translational modifications of histones by protein methyltransferases (PMTs) and histone demethylases (KDMs) play an important role in the regulation of gene expression and transcription and are implicated in cancer and many other diseases. Many of these enzymes also target various nonhistone proteins impacting numerous crucial biological pathways. Given their key biological functions and implications in human diseases, there has been a growing interest in assessing these enzymes as potential therapeutic targets. Consequently, discovering and developing inhibitors of these enzymes has become a very active and fast-growing research area over the past decade. In this review, we cover the discovery, characterization, and biological application of inhibitors of PMTs and KDMs with emphasis on key advancements in the field. We also discuss challenges, opportunities, and future directions in this emerging, exciting research field. PMID:28338320
Shields, Richard K.; Dudley-Javoroski, Shauna; Littmann, Andrew E.
2012-01-01
Understanding the torque output behavior of paralyzed muscle has important implications for the use of functional neuromuscular electrical stimulation systems. Postfatigue potentiation is an augmentation of peak muscle torque during repetitive activation after a fatigue protocol. The purposes of this study were 1) to quantify postfatigue potentiation in the acutely and chronically paralyzed soleus and 2) to determine the effect of long-term soleus electrical stimulation training on the potentiation characteristics of recently paralyzed soleus muscle. Five subjects with chronic paralysis (>2 yr) demonstrated significant postfatigue potentiation during a repetitive soleus activation protocol that induced low-frequency fatigue. Ten subjects with acute paralysis (<6 mo) demonstrated no torque potentiation in response to repetitive stimulation. Seven of these acute subjects completed 2 yr of home-based isometric soleus electrical stimulation training of one limb (compliance = 83%; 8,300 contractions/wk). With the early implementation of electrically stimulated training, potentiation characteristics of trained soleus muscles were preserved as in the acute postinjury state. In contrast, untrained limbs showed marked postfatigue potentiation at 2 yr after spinal cord injury (SCI). A single acute SCI subject who was followed longitudinally developed potentiation characteristics very similar to the untrained limbs of the training subjects. The results of the present investigation support that postfatigue potentiation is a characteristic of fast-fatigable muscle and can be prevented by timely neuromuscular electrical stimulation training. Potentiation is an important consideration in the design of functional electrical stimulation control systems for people with SCI. PMID:16575026
Shields, Richard K; Dudley-Javoroski, Shauna; Littmann, Andrew E
2006-08-01
Understanding the torque output behavior of paralyzed muscle has important implications for the use of functional neuromuscular electrical stimulation systems. Postfatigue potentiation is an augmentation of peak muscle torque during repetitive activation after a fatigue protocol. The purposes of this study were 1) to quantify postfatigue potentiation in the acutely and chronically paralyzed soleus and 2) to determine the effect of long-term soleus electrical stimulation training on the potentiation characteristics of recently paralyzed soleus muscle. Five subjects with chronic paralysis (>2 yr) demonstrated significant postfatigue potentiation during a repetitive soleus activation protocol that induced low-frequency fatigue. Ten subjects with acute paralysis (<6 mo) demonstrated no torque potentiation in response to repetitive stimulation. Seven of these acute subjects completed 2 yr of home-based isometric soleus electrical stimulation training of one limb (compliance = 83%; 8,300 contractions/wk). With the early implementation of electrically stimulated training, potentiation characteristics of trained soleus muscles were preserved as in the acute postinjury state. In contrast, untrained limbs showed marked postfatigue potentiation at 2 yr after spinal cord injury (SCI). A single acute SCI subject who was followed longitudinally developed potentiation characteristics very similar to the untrained limbs of the training subjects. The results of the present investigation support that postfatigue potentiation is a characteristic of fast-fatigable muscle and can be prevented by timely neuromuscular electrical stimulation training. Potentiation is an important consideration in the design of functional electrical stimulation control systems for people with SCI.
Finn, Emily S; Todd Constable, R
2016-09-01
Functional brain connectivity measured with functional magnetic resonance imaging (fMRI) is a popular technique for investigating neural organization in both healthy subjects and patients with mental illness. Despite a rapidly growing body of literature, however, functional connectivity research has yet to deliver biomarkers that can aid psychiatric diagnosis or prognosis at the single-subject level. One impediment to developing such practical tools has been uncertainty regarding the ratio of intra- to interindividual variability in functional connectivity; in other words, how much variance is state- versus trait-related. Here, we review recent evidence that functional connectivity profiles are both reliable within subjects and unique across subjects, and that features of these profiles relate to behavioral phenotypes. Together, these results suggest the potential to discover reliable correlates of present and future illness and/or response to treatment in the strength of an individual's functional brain connections. Ultimately, this work could help develop personalized approaches to psychiatric illness.
Timmons, Adela C.; Margolin, Gayla; Saxbe, Darby E.
2015-01-01
Do partners’ levels of physiological arousal become linked in close relationships? The term “physiological linkage” describes covariation between people in their moment-to-moment physiological states. The current review presents a conceptual framework to guide research on linkage in romantic relationships and discusses the potential implications of being “linked.” Evidence of linkage was found across a broad range of physiological indices and in a variety of contexts, including during laboratory-based conflict and in daily life. Four hypotheses regarding how linkage relates to individual and interpersonal functioning are evaluated: (1) co-activation of the sympathetic nervous system or hypothalamic-pituitary adrenal axis is “bad,” (2) moderate physiological linkage is “just right,” (3) physiological linkage is problematic if the individual or couple is overloaded, and (4) the implications of physiological linkage depend on the emotional context. We found partial support for the first hypothesis and determined that more research is needed to evaluate the remaining hypotheses. Linkage in cortisol was negatively associated with relationship satisfaction; but at the same time, linkage in multiple systems was positively associated with indices of relationship connectedness, such as the amount of time spent together and the ability to identify the emotions of one’s partner. These results suggest that linkage may confer benefits but also may put couples at risk if they become entrenched in patterns of conflict or stress. With research in this area burgeoning in recent years, this review indicates that linkage is a promising construct with applications for interventions targeting individual health and couple functioning. PMID:26147932
Said-Mohamed, Rihlat; Pettifor, John M; Norris, Shane A
2018-01-01
Life history theory integrates ecological, physiological, and molecular layers within an evolutionary framework to understand organisms' strategies to optimize survival and reproduction. Two life history hypotheses and their implications for child growth, development, and health (illustrated in the South African context) are reviewed here. One hypothesis suggests that there is an energy trade-off between linear growth and brain growth. Undernutrition in infancy and childhood may trigger adaptive physiological mechanisms prioritizing the brain at the expense of body growth. Another hypothesis is that the period from conception to infancy is a critical window of developmental plasticity of linear growth, the duration of which may vary between and within populations. The transition from infancy to childhood may mark the end of a critical window of opportunity for improving child growth. Both hypotheses emphasize the developmental plasticity of linear growth and the potential determinants of growth variability (including the role of parent-offspring conflict in maternal resources allocation). Implications of these hypotheses in populations with high burdens of undernutrition and infections are discussed. In South Africa, HIV/AIDS during pregnancy (associated with adverse birth outcomes, short duration of breastfeeding, and social consequences) may lead to a shortened window of developmental plasticity of growth. Furthermore, undernutrition and infectious diseases in children living in South Africa, a country undergoing a rapid nutrition transition, may have adverse consequences on individuals' cognitive abilities and risks of cardio-metabolic diseases. Studies are needed to identify physiological mechanisms underlying energy allocation between biological functions and their potential impacts on health. © 2017 Wiley Periodicals, Inc.
Li, Chaoqun; Cao, Feifei; Li, Shengli; Huang, Shenglin; Li, Wei; Abumaria, Nashat
2018-01-01
Although studies provide insights into the neurobiology of stress and depression, the exact molecular mechanisms underlying their pathologies remain largely unknown. Long non-coding RNA (lncRNA) has been implicated in brain functions and behavior. A potential link between lncRNA and psychiatric disorders has been proposed. However, it remains undetermined whether IncRNA regulation, in the brain, contributes to stress or depression pathologies. In this study, we used a valid animal model of depression-like symptoms; namely learned helplessness, RNA-seq, Gene Ontology and co-expression network analyses to profile the expression pattern of lncRNA and mRNA in the hippocampus of mice. We identified 6346 differentially expressed transcripts. Among them, 340 lncRNAs and 3559 protein coding mRNAs were differentially expressed in helpless mice in comparison with control and/or non-helpless mice (inescapable stress resilient mice). Gene Ontology and pathway enrichment analyses indicated that induction of helplessness altered expression of mRNAs enriched in fundamental biological functions implicated in stress/depression neurobiology such as synaptic, metabolic, cell survival and proliferation, developmental and chromatin modification functions. To explore the possible regulatory roles of the altered lncRNAs, we constructed co-expression networks composed of the lncRNAs and mRNAs. Among our differentially expressed lncRNAs, 17% showed significant correlation with genes. Functional co-expression analysis linked the identified lncRNAs to several cellular mechanisms implicated in stress/depression neurobiology. Importantly, 57% of the identified regulatory lncRNAs significantly correlated with 18 different synapse-related functions. Thus, the current study identifies for the first time distinct groups of lncRNAs regulated by induction of learned helplessness in the mouse brain. Our results suggest that lncRNA-directed regulatory mechanisms might contribute to stress-induced pathologies; in particular, to inescapable stress-induced synaptic modifications. PMID:29375311
Li, Chaoqun; Cao, Feifei; Li, Shengli; Huang, Shenglin; Li, Wei; Abumaria, Nashat
2017-01-01
Although studies provide insights into the neurobiology of stress and depression, the exact molecular mechanisms underlying their pathologies remain largely unknown. Long non-coding RNA (lncRNA) has been implicated in brain functions and behavior. A potential link between lncRNA and psychiatric disorders has been proposed. However, it remains undetermined whether IncRNA regulation, in the brain, contributes to stress or depression pathologies. In this study, we used a valid animal model of depression-like symptoms; namely learned helplessness, RNA-seq, Gene Ontology and co-expression network analyses to profile the expression pattern of lncRNA and mRNA in the hippocampus of mice. We identified 6346 differentially expressed transcripts. Among them, 340 lncRNAs and 3559 protein coding mRNAs were differentially expressed in helpless mice in comparison with control and/or non-helpless mice (inescapable stress resilient mice). Gene Ontology and pathway enrichment analyses indicated that induction of helplessness altered expression of mRNAs enriched in fundamental biological functions implicated in stress/depression neurobiology such as synaptic, metabolic, cell survival and proliferation, developmental and chromatin modification functions. To explore the possible regulatory roles of the altered lncRNAs, we constructed co-expression networks composed of the lncRNAs and mRNAs. Among our differentially expressed lncRNAs, 17% showed significant correlation with genes. Functional co-expression analysis linked the identified lncRNAs to several cellular mechanisms implicated in stress/depression neurobiology. Importantly, 57% of the identified regulatory lncRNAs significantly correlated with 18 different synapse-related functions. Thus, the current study identifies for the first time distinct groups of lncRNAs regulated by induction of learned helplessness in the mouse brain. Our results suggest that lncRNA-directed regulatory mechanisms might contribute to stress-induced pathologies; in particular, to inescapable stress-induced synaptic modifications.
Chevalier, Benoit; Puisségur, Marie-Pierre; Lebrigand, Kevin; Robbe-Sermesant, Karine; Bertero, Thomas; Lino Cardenas, Christian L.; Courcot, Elisabeth; Rios, Géraldine; Fourre, Sandra; Lo-Guidice, Jean-Marc; Marcet, Brice; Cardinaud, Bruno; Barbry, Pascal; Mari, Bernard
2009-01-01
Background Epithelial-mesenchymal interactions are critical in regulating many aspects of vertebrate embryo development, and for the maintenance of homeostatic equilibrium in adult tissues. The interactions between epithelium and mesenchyme are believed to be mediated by paracrine signals such as cytokines and extracellular matrix components secreted from fibroblasts that affect adjacent epithelia. In this study, we sought to identify the repertoire of microRNAs (miRNAs) in normal lung human fibroblasts and their potential regulation by the cytokines TNF-α, IL-1β and TGF-β. Methodology/Principal Findings MiR-155 was significantly induced by inflammatory cytokines TNF-α and IL-1β while it was down-regulated by TGF-β. Ectopic expression of miR-155 in human fibroblasts induced modulation of a large set of genes related to “cell to cell signalling”, “cell morphology” and “cellular movement”. This was consistent with an induction of caspase-3 activity and with an increase in cell migration in fibroblasts tranfected with miR-155. Using different miRNA bioinformatic target prediction tools, we found a specific enrichment for miR-155 predicted targets among the population of down-regulated transcripts. Among fibroblast-selective targets, one interesting hit was keratinocyte growth factor (KGF, FGF-7), a member of the fibroblast growth factor (FGF) family, which owns two potential binding sites for miR-155 in its 3′-UTR. Luciferase assays experimentally validated that miR-155 can efficiently target KGF 3′-UTR. Site-directed mutagenesis revealed that only one out of the 2 potential sites was truly functional. Functional in vitro assays experimentally validated that miR-155 can efficiently target KGF 3′-UTR. Furthermore, in vivo experiments using a mouse model of lung fibrosis showed that miR-155 expression level was correlated with the degree of lung fibrosis. Conclusions/Significance Our results strongly suggest a physiological function of miR-155 in lung fibroblasts. Altogether, this study implicates this miRNA in the regulation by mesenchymal cells of surrounding lung epithelium, making it a potential key player during tissue injury. PMID:19701459
Chromatin Remodeling Function of BRCA1 and Its Implication in Regulation of DNA Replication
2001-09-01
Remodeling Function of BRCAI and its Implication in Regulation of DNA Replication PRINCIPAL INVESTIGATOR: Rong Li, Ph.D. CONTRACTING ORGANIZATION: University...of BRCAI and its Implication DAMD17-99-1-9572 in Regulation of DNA Replication 6. AUTHOR(S) Rong Li, Ph.D. 7. PERFORMING ORGANIZATION NAME(S) AND...1-mediated nuclear functions. 14. SUBJECT TERMS 15. NUMBER OF PAGES Breast Cancer, DNA replication , chromatin remodeling, transcription, 19 cell cycle
Unique catalytic activities and scaffolding of p21 activated kinase-1 in cardiovascular signaling.
Ke, Yunbo; Lei, Ming; Wang, Xin; Solaro, R John
2013-09-27
P21 activated kinase-1 (Pak1) has diverse functions in mammalian cells. Although a large number of phosphoproteins have been designated as Pak1 substrates from in vitro studies, emerging evidence has indicated that Pak1 may function as a signaling molecule through a unique molecular mechanism - scaffolding. By scaffolding, Pak1 delivers signals through an auto-phosphorylation-induced conformational change without transfer of a phosphate group to its immediate downstream effector(s). Here we review evidence for this regulatory mechanism based on structural and functional studies of Pak1 in different cell types and research models as well as in vitro biochemical assays. We also discuss the implications of Pak1 scaffolding in disease-related signaling processes and the potential in cardiovascular drug development.
FKBP51 and FKBP52 in Signaling and Disease
Storer, Cheryl L.; Dickey, Chad A.; Galigniana, Mario D.; Rein, Theo; Cox, Marc B.
2011-01-01
FKBP51 and FKBP52 are diverse regulators of steroid hormone receptor signaling including regulation of receptor maturation, hormone binding, and nuclear translocation. Although structurally similar, they are functionally divergent, which is largely attributed to differences in the FK1 domain and the proline-rich loop. FKBP51 and FKBP52 have emerged as likely contributors to a variety of hormone-dependent diseases including stress-related diseases, immune function, reproductive functions and a variety of cancers. In addition, recent studies have implicated FKBP51 and FKBP52 in Alzheimer’s disease and other protein aggregation disorders. This review summarizes our current understanding of FKBP51 and FKBP52 interactions within the receptor-chaperone complex, their contributions to health and disease, and their potential as therapeutic targets for the treatment of these diseases. PMID:21889356
The Emerging Role of Epigenetics in Inflammation and Immunometabolism.
Raghuraman, Sukanya; Donkin, Ida; Versteyhe, Soetkin; Barrès, Romain; Simar, David
2016-11-01
Recent research developments have shed light on the risk factors contributing to metabolic complications, implicating both genetic and environmental factors, potentially integrated by epigenetic mechanisms. Distinct epigenetic changes in immune cells are frequently observed in obesity and type 2 diabetes mellitus, and these are associated with alterations in the phenotype, function, and trafficking patterns of these cells. The first step in the development of effective therapeutic strategies is the identification of distinct epigenetic signatures associated with metabolic disorders. In this review we provide an overview of the epigenetic mechanisms influencing immune cell phenotype and function, summarize current knowledge about epigenetic changes affecting immune functions in the context of metabolic diseases, and discuss the therapeutic options currently available to counteract epigenetically driven metabolic complications. Copyright © 2016 Elsevier Ltd. All rights reserved.
Cornils, Hauke; Kohler, Reto S; Hergovich, Alexander; Hemmings, Brian A
2011-06-15
The mammalian genome encodes four members of the NDR/LATS kinase family: NDR1 (STK38), NDR2 (STK38L), LATS1 and LATS2, which are highly conserved from yeast to man. Members of the NDR/LATS kinase family have been implicated in a variety of biological processes ranging from cell division and morphology to apoptosis and tumor suppression. In mammals, LATS1/2 function as central parts of the HIPPO tumor suppressor pathway by restricting the activity of the YAP/TAZ proto-oncogenes. Recent evidence suggested that NDR1/2 are also part of an extended HIPPO tumor suppressor pathway. Apart from functions in apoptosis signaling and tumor suppression, NDR1/2 have been implicated in controlling centrosome duplication and mitotic chromosome alignment downstream of the HIPPO kinase homologs MST1 and MST2. Significantly, we also reported recently that NDR1/2 are controlling G 1/S transition downstream of a third MST family member MST3. Intriguingly, this newly described MST3-NDR1/2 axis promotes G 1 progression by stabilizing c-myc and preventing p21 accumulation, indicating a potential pro-tumorigenic role for NDR kinases. Here, we discuss these novel cell cycle functions of NDR kinases in a broader context and elaborate on possible explanations for the opposing functions of NDR kinases in normal and tumor biology.
Marzluff, John
2017-01-01
Emerging evidence that cities drive micro-evolution raises the question of whether rapid urbanization of Earth might impact ecosystems by causing systemic changes in functional traits that regulate urban ecosystems' productivity and stability. Intraspecific trait variation—variation in organisms' morphological, physiological or behavioural characteristics stemming from genetic variability and phenotypic plasticity—has significant implications for ecological functions such as nutrient cycling and primary productivity. While it is well established that changes in ecological conditions can drive evolutionary change in species' traits that, in turn, can alter ecosystem function, an understanding of the reciprocal and simultaneous processes associated with such interactions is only beginning to emerge. In urban settings, the potential for rapid trait change may be exacerbated by multiple selection pressures operating simultaneously. This paper reviews evidence on mechanisms linking urban development patterns to rapid phenotypic changes, and differentiates phenotypic changes for which there is evidence of micro-evolution versus phenotypic changes which may represent plasticity. Studying how humans mediate phenotypic trait changes through urbanization could shed light on fundamental concepts in ecological and evolutionary theory. It can also contribute to our understanding of eco-evolutionary feedback and provide insights for maintaining ecosystem function over the long term. This article is part of the themed issue ‘Human influences on evolution, and the ecological and societal consequences’. PMID:27920374
Exarchos, Konstantinos P; Exarchos, Themis P; Rigas, Georgios; Papaloukas, Costas; Fotiadis, Dimitrios I
2011-05-10
In peptides and proteins, only a small percentile of peptide bonds adopts the cis configuration. Especially in the case of amide peptide bonds, the amount of cis conformations is quite limited thus hampering systematic studies, until recently. However, lately the emerging population of databases with more 3D structures of proteins has produced a considerable number of sequences containing non-proline cis formations (cis-nonPro). In our work, we extract regular expression-type patterns that are descriptive of regions surrounding the cis-nonPro formations. For this purpose, three types of pattern discovery are performed: i) exact pattern discovery, ii) pattern discovery using a chemical equivalency set, and iii) pattern discovery using a structural equivalency set. Afterwards, using each pattern as predicate, we search the Eukaryotic Linear Motif (ELM) resource to identify potential functional implications of regions with cis-nonPro peptide bonds. The patterns extracted from each type of pattern discovery are further employed, in order to formulate a pattern-based classifier, which is used to discriminate between cis-nonPro and trans-nonPro formations. In terms of functional implications, we observe a significant association of cis-nonPro peptide bonds towards ligand/binding functionalities. As for the pattern-based classification scheme, the highest results were obtained using the structural equivalency set, which yielded 70% accuracy, 77% sensitivity and 63% specificity.
Jayaraman, Shobini; Haupt, Christian; Gursky, Olga
2015-01-01
Serum amyloid A (SAA) is an acute-phase protein that circulates mainly on plasma HDL. SAA interactions with its functional ligands and its pathogenic deposition in reactive amyloidosis depend, in part, on the structural disorder of this protein and its propensity to oligomerize. In vivo, SAA can displace a substantial fraction of the major HDL protein, apoA-I, and thereby influence the structural remodeling and functions of acute-phase HDL in ways that are incompletely understood. We use murine SAA1.1 to report the first structural stability study of human plasma HDL that has been enriched with SAA. Calorimetric and spectroscopic analyses of these and other SAA-lipid systems reveal two surprising findings. First, progressive displacement of the exchangeable fraction of apoA-I by SAA has little effect on the structural stability of HDL and its fusion and release of core lipids. Consequently, the major determinant for HDL stability is the nonexchangeable apoA-I. A structural model explaining this observation is proposed, which is consistent with functional studies in acute-phase HDL. Second, we report an α-helix folding/unfolding transition in SAA in the presence of lipid at near-physiological temperatures. This new transition may have potentially important implications for normal functions of SAA and its pathogenic misfolding. PMID:26022803
NASA Astrophysics Data System (ADS)
Fyodorov, Yan V.; Bouchaud, Jean-Philippe
2008-09-01
We investigate some implications of the freezing scenario proposed by Carpentier and Le Doussal (CLD) for a random energy model (REM) with logarithmically correlated random potential. We introduce a particular (circular) variant of the model, and show that the integer moments of the partition function in the high-temperature phase are given by the well-known Dyson Coulomb gas integrals. The CLD freezing scenario allows one to use those moments for extracting the distribution of the free energy in both high- and low-temperature phases. In particular, it yields the full distribution of the minimal value in the potential sequence. This provides an explicit new class of extreme-value statistics for strongly correlated variables, manifestly different from the standard Gumbel class.
Strategies to enhance the bioavailability of curcumin: a potential antitumor drug
NASA Astrophysics Data System (ADS)
Kumar, Abhishek; Chittigori, Joshna; Li, Lian; Samuelson, Lynne; Sandman, Daniel; Kumar, Jayant
2012-02-01
Curcumin is a polyphenol which has elicited considerable interest for its antioxidant and anti tumor properties. Although curcumin may be used as potential therapeutic drug, it is very sparingly soluble in water which makes it less bioavailable under physiological conditions. We report two approaches to make curcumin more bioavailable. The first approach involves fabricating colloidal dispersions of curcumin in the range of tens of nanometers. The second approach involves functionalization of curcumin with polyethylene glycol (PEG) to render it water dispersible or soluble. Since curcumin is a fluorescent molecule as well as a potential drug, its interactions with cells have been investigated using one and two photon confocal fluorescence imaging. We have also observed strong interaction between curcumin and metal ions, which may have physiological implications.
Mitochondrial abnormalities in Alzheimer’s disease: Possible targets for therapeutic intervention
Silva, Diana F.; Selfridge, J. Eva; Lu, Jianghua; Lezi, E; Cardoso, Sandra M.; Swerdlow, Russell H.
2013-01-01
Mitochondria from persons with Alzheimer’s disease (AD) differ from those of age-matched, control subjects. Differences in mitochondrial morphology and function are well-documented, and are not brain-limited. Some of these differences are present during all stages of AD, and are even seen in individuals who are without AD symptoms and signs but who have an increased risk of developing AD. This chapter considers the status of mitochondria in AD subjects, the potential basis for AD subject mitochondrial perturbations, and the implications of these perturbations. Data from multiple lines of investigation, including epidemiologic, biochemical, molecular, and cytoplasmic hybrid studies are reviewed. The possibility that mitochondria could potentially constitute a reasonable AD therapeutic target is discussed, as are several potential mitochondrial medicine treatment strategies. PMID:22840745
Physiological functions and pathogenic potential of uric acid: A review.
El Ridi, Rashika; Tallima, Hatem
2017-09-01
Uric acid is synthesized mainly in the liver, intestines and the vascular endothelium as the end product of an exogenous pool of purines, and endogenously from damaged, dying and dead cells, whereby nucleic acids, adenine and guanine, are degraded into uric acid. Mentioning uric acid generates dread because it is the established etiological agent of the severe, acute and chronic inflammatory arthritis, gout and is implicated in the initiation and progress of the metabolic syndrome. Yet, uric acid is the predominant anti-oxidant molecule in plasma and is necessary and sufficient for induction of type 2 immune responses. These properties may explain its protective potential in neurological and infectious diseases, mainly schistosomiasis. The pivotal protective potential of uric acid against blood-borne pathogens and neurological and autoimmune diseases is yet to be established.
Genetic Otx2 mis-localization delays critical period plasticity across brain regions.
Lee, H H C; Bernard, C; Ye, Z; Acampora, D; Simeone, A; Prochiantz, A; Di Nardo, A A; Hensch, T K
2017-05-01
Accumulation of non-cell autonomous Otx2 homeoprotein in postnatal mouse visual cortex (V1) has been implicated in both the onset and closure of critical period (CP) plasticity. Here, we show that a genetic point mutation in the glycosaminoglycan recognition motif of Otx2 broadly delays the maturation of pivotal parvalbumin-positive (PV+) interneurons not only in V1 but also in the primary auditory (A1) and medial prefrontal cortex (mPFC). Consequently, not only visual, but also auditory plasticity is delayed, including the experience-dependent expansion of tonotopic maps in A1 and the acquisition of acoustic preferences in mPFC, which mitigates anxious behavior. In addition, Otx2 mis-localization leads to dynamic turnover of selected perineuronal net (PNN) components well beyond the normal CP in V1 and mPFC. These findings reveal widespread actions of Otx2 signaling in the postnatal cortex controlling the maturational trajectory across modalities. Disrupted PV+ network function and deficits in PNN integrity are implicated in a variety of psychiatric illnesses, suggesting a potential global role for Otx2 function in establishing mental health.
High Antibacterial Activity of Functionalized Chemically Exfoliated MoS2.
Pandit, Subhendu; Karunakaran, Subbaraj; Boda, Sunil Kumar; Basu, Bikramjit; De, Mrinmoy
2016-11-23
In view of the implications of inherent resistance of pathogenic bacteria, especially ESKAPE pathogens toward most of the commercially available antibiotics and the importance of these bacteria-induced biofilm formation leading to chronic infection, it is important to develop new-generation synthetic materials with greater efficacy toward antibacterial property. In addressing this issue, this paper reports a proof-of-principle study to evaluate the potential of functionalized two-dimensional chemically exfoliated MoS 2 (ce-MoS 2 ) toward inhibitory and bactericidal property against two representative ESKAPE pathogenic strain-a Gram-positive Staphylococcus aureus (MRSA) and a Gram-negative Pseudomonas aeruginosa. More significantly, the mechanistic study establishes a different extent of oxidative stress together with rapid membrane depolarization in contact with ce-MoS 2 having ligands of varied charge and hydrophobicity. The implication of our results is discussed in the light of the lack of survivability of planktonic bacteria and biofilm destruction in vitro. A comparison with widely used small molecules and other nanomaterial-based therapeutics conclusively establishes a better efficacy of 2D ce-MoS 2 as a new class of antibiotics.
Harikumar, Kaleeckal G.; Miller, Laurence J.; Chow, Billy K. C.
2016-01-01
The involvement of secretin (SCT) and secretin receptor (SCTR) in regulating body water homeostasis is well established. Identified as one of the vasopressin (Vp)-independent mechanisms in fluid balance, SCT regulates aquaporin 2 (AQP2) in the kidney distal collecting duct cells through activating intracellular cAMP production. This ability to bypass Vp-mediated water reabsorption in kidney implicates SCT’s potential to treat nephrogenic diabetes insipidus (NDI). Research on NDI in the past has largely been focused on the searching for mutations in vasopressin receptor 2 (AVPR2), while the functional relationship between SCTR, AVPR2 and NDI remains unclear. Here, we demonstrate the interaction between SCTR and AVPR2 to modulate cellular signaling in vitro. Interestingly, we show in this report that upon heteromer formation with SCTR, R137H, a NDI-causing AVPR2 mutant that is defective in trafficking to cell surface, can functionally be rescued. Our data may provide an explanation for this clinically mild case of NDI, and insights into the pathological development of NDI in the future. PMID:27649563
The Role of TAM Family Receptors in Immune Cell Function: Implications for Cancer Therapy.
Paolino, Magdalena; Penninger, Josef M
2016-10-21
The TAM receptor protein tyrosine kinases-Tyro3, Axl, and Mer-are essential regulators of immune homeostasis. Guided by their cognate ligands Growth arrest-specific gene 6 (Gas6) and Protein S (Pros1), these receptors ensure the resolution of inflammation by dampening the activation of innate cells as well as by restoring tissue function through promotion of tissue repair and clearance of apoptotic cells. Their central role as negative immune regulators is highlighted by the fact that deregulation of TAM signaling has been linked to the pathogenesis of autoimmune, inflammatory, and infectious diseases. Importantly, TAM receptors have also been associated with cancer development and progression. In a cancer setting, TAM receptors have a dual regulatory role, controlling the initiation and progression of tumor development and, at the same time, the associated anti-tumor responses of diverse immune cells. Thus, modulation of TAM receptors has emerged as a potential novel strategy for cancer treatment. In this review, we discuss our current understanding of how TAM receptors control immunity, with a particular focus on the regulation of anti-tumor responses and its implications for cancer immunotherapy.
Autophagy: a new player in skeletal maintenance?
Hocking, Lynne J; Whitehouse, Caroline; Helfrich, Miep H
2012-07-01
Imbalances between bone resorption and formation lie at the root of disorders such as osteoporosis, Paget's disease of bone (PDB), and osteopetrosis. Recently, genetic and functional studies have implicated proteins involved in autophagic protein degradation as important mediators of bone cell function in normal physiology and in pathology. Autophagy is the conserved process whereby aggregated proteins, intracellular pathogens, and damaged organelles are degraded and recycled. This process is important both for normal cellular quality control and in response to environmental or internal stressors, particularly in terminally-differentiated cells. Autophagic structures can also act as hubs for the spatial organization of recycling and synthetic process in secretory cells. Alterations to autophagy (reduction, hyperactivation, or impairment) are associated with a number of disorders, including neurodegenerative diseases and cancers, and are now being implicated in maintenance of skeletal homoeostasis. Here, we introduce the topic of autophagy, describe the new findings that are starting to emerge from the bone field, and consider the therapeutic potential of modifying this pathway for the treatment of age-related bone disorders. Copyright © 2012 American Society for Bone and Mineral Research.
The Role of Innate and Adaptive Immunity in Parkinson's Disease
Kannarkat, George T.; Boss, Jeremy M.; Tansey, Malú G.
2014-01-01
In recent years, inflammation has become implicated as a major pathogenic factor in the onset and progression of Parkinson's disease. Understanding the precise role for inflammation in PD will likely lead to understanding of how sporadic disease arises. In vivo evidence for inflammation in PD includes microglial activation, increased expression of inflammatory genes in the periphery and in the central nervous system (CNS), infiltration of peripheral immune cells into the CNS, and altered composition and phenotype of peripheral immune cells. These findings are recapitulated in various animal models of PD and are reviewed herein. Furthermore, we examine the potential relevance of PD-linked genetic mutations to altered immune function and the extent to which environmental exposures that recapitulate these phenotypes, which may lead to sporadic PD through similar mechanisms. Given the implications of immune system involvement on disease progression, we conclude by reviewing the evidence supporting the potential efficacy of immunomodulatory therapies in PD prevention or treatment. There is a clear need for additional research to clarify the role of immunity and inflammation in this chronic, neurodegenerative disease. PMID:24275605
Lavie, Carl J; McAuley, Paul A; Church, Timothy S; Milani, Richard V; Blair, Steven N
2014-04-15
Obesity has been increasing in epidemic proportions, with a disproportionately higher increase in morbid or class III obesity, and obesity adversely affects cardiovascular (CV) hemodynamics, structure, and function, as well as increases the prevalence of most CV diseases. Progressive declines in physical activity over 5 decades have occurred and have primarily caused the obesity epidemic. Despite the potential adverse impact of overweight and obesity, recent epidemiological data have demonstrated an association of mild obesity and, particularly, overweight on improved survival. We review in detail the obesity paradox in CV diseases where overweight and at least mildly obese patients with most CV diseases seem to have a better prognosis than do their leaner counterparts. The implications of cardiorespiratory fitness with prognosis are discussed, along with the joint impact of fitness and adiposity on the obesity paradox. Finally, in light of the obesity paradox, the potential value of purposeful weight loss and increased physical activity to affect levels of fitness is reviewed. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Child, M. S.; Bernstein, R. B.
1973-01-01
Spectroscopically derived potential curves for the low-lying excited states of homonuclear and heteronuclear diatomic interhalogens are systematized by the spin-orbit state of their dissociation products. The implications of spectroscopic interatomic potentials and curve crossings are discussed.
TRP channels in the digestive system
Holzer, Peter
2011-01-01
Several of the 28 mammalian transient receptor potential (TRP) channel subunits are expressed throughout the alimentary canal where they play important roles in taste, chemo- and mechanosensation, thermoregulation, pain and hyperalgesia, mucosal function and homeostasis, control of motility by neurons, interstitial cells of Cajal and muscle cells, and vascular function. While the implications of some TRP channels, notably TRPA1, TRPC4, TRPM5, TRPM6, TRPM7, TRPV1, TRPV4, and TRPV6, have been investigated in much detail, the understanding of other TRP channels in their relevance to digestive function lags behind. The polymodal chemo- and mechanosensory function of TRPA1, TRPM5, TRPV1 and TRPV4 is particularly relevant to the alimentary canal whose digestive and absorptive function depends on the surveillance and integration of many chemical and physical stimuli. TRPV5 and TRPV6 as well as TRPM6 and TRPM7 appear to be essential for the absorption of Ca2+ and Mg2+, respectively, while TRPM7 appears to contribute to the pacemaker activity of the interstitial cells of Cajal, and TRPC4 transduces smooth muscle contraction evoked by muscarinic acetylcholine receptor activation. The implication of some TRP channels in pathological processes has raised enormous interest in exploiting them as a therapeutic target. This is particularly true for TRPV1, TRPV4 and TRPA1, which may be targeted for the treatment of several conditions of chronic abdominal pain. Consequently, blockers of these TRP channels have been developed, and their clinical usefulness has yet to be established. PMID:20932260
Iraq’s Debt Relief: Procedure and Potential Implications for International Debt Relief
2008-10-02
Order Code RL33376 Iraq’s Debt Relief: Procedure and Potential Implications for International Debt Relief Updated October 2, 2008 Martin A. Weiss...4. TITLE AND SUBTITLE Iraq?s Debt Relief: Procedure and Potential Implications for International Debt Relief 5a. CONTRACT NUMBER 5b. GRANT NUMBER...b. ABSTRACT unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 Iraq’s Debt Relief: Procedure
Potential role of Arabidopsis PHP as an accessory subunit of the PAF1 transcriptional cofactor.
Park, Sunchung; Ek-Ramos, Maria Julissa; Oh, Sookyung; van Nocker, Steven
2011-08-01
Paf1C is a transcriptional cofactor that has been implicated in various transcription-associated mechanisms spanning initiation, elongation and RNA processing, and is important for multiple aspects of development in Arabidopsis. Our recent studies suggest Arabidopsis Paf1C is crucial for proper regulation of genes within H3K27me3-enriched chromatin, and that a protein named PHP may act as an accessory subunit of Paf1C that promotes this function.
Role of Endoplasmic Reticulum Stress in Metabolic Disease and Other Disorders
Ozcan, Lale; Tabas, Ira
2012-01-01
Perturbations in the normal functions of the endoplasmic reticulum (ER) trigger a signaling network that coordinates adaptive and apoptotic responses. There is accumulating evidence implicating prolonged ER stress in the development and progression of many diseases, including neurodegeneration, atherosclerosis, type 2 diabetes, liver disease, and cancer. With the improved understanding of the underlying molecular mechanisms, therapeutic interventions that target the ER stress response would be potential strategies to treat various diseases driven by prolonged ER stress. PMID:22248326
Evolution and function of the upper molar talon and its dietary implications in microbats.
Gutzwiller, Sarah C; Hunter, John P
2015-11-01
The evolution of mammalian molars has been marked by transitions representing significant changes in shape and function. One such transition is the addition and elaboration of the talon, the distolingual region of the ancestral tribosphenic upper molar of therian mammals and some extinct relatives. This study uses suborder Microchiroptera as a case study to explore the adaptive implications of the expansion of the talon on the tribosphenic molar, specifically focusing on the talon's role in the compression and shear of food during breakdown. Three-dimensional computer renderings of casts of the upper left first molars were created for microbat species of a variety of dietary categories (frugivore, etc.) and physical properties of food (hard and soft). Relief Index (RFI) was measured to estimate the topography and function of the whole tooth and of the talon and trigon (the remaining primitive tribosphenic region) individually, in order to examine 1) how the shape of the whole tooth, trigon, and talon reflects the compromise between their crushing and shearing functions, 2) how whole tooth, trigon, and talon function differs according to diet, and 3) how the presence of the talon affects overall molar function. Results suggest that RFI of both the whole tooth and the trigon varies according to dietary groups, with frugivores having greater crushing function when compared with the other groups. The talon, however, consistently has low RFI (a flatter topography), and its presence lowers the RFI of the whole tooth across all dietary categories, suggesting that the talon is primarily functioning in crushing during food breakdown. The potential benefits of a crushing talon for microbats of various dietary groups are discussed. © 2015 Wiley Periodicals, Inc.
Kujur, Alice; Bajaj, Deepak; Saxena, Maneesha S.; Tripathi, Shailesh; Upadhyaya, Hari D.; Gowda, C.L.L.; Singh, Sube; Jain, Mukesh; Tyagi, Akhilesh K.; Parida, Swarup K.
2013-01-01
We developed 1108 transcription factor gene-derived microsatellite (TFGMS) and 161 transcription factor functional domain-associated microsatellite (TFFDMS) markers from 707 TFs of chickpea. The robust amplification efficiency (96.5%) and high intra-specific polymorphic potential (34%) detected by markers suggest their immense utilities in efficient large-scale genotyping applications, including construction of both physical and functional transcript maps and understanding population structure. Candidate gene-based association analysis revealed strong genetic association of TFFDMS markers with three major seed and pod traits. Further, TFGMS markers in the 5′ untranslated regions of TF genes showing differential expression during seed development had higher trait association potential. The significance of TFFDMS markers was demonstrated by correlating their allelic variation with amino acid sequence expansion/contraction in the functional domain and alteration of secondary protein structure encoded by genes. The seed weight-associated markers were validated through traditional bi-parental genetic mapping. The determination of gene-specific linkage disequilibrium (LD) patterns in desi and kabuli based on single nucleotide polymorphism-microsatellite marker haplotypes revealed extended LD decay, enhanced LD resolution and trait association potential of genes. The evolutionary history of a strong seed-size/weight-associated TF based on natural variation and haplotype sharing among desi, kabuli and wild unravelled useful information having implication for seed-size trait evolution during chickpea domestication. PMID:23633531
Therapeutic Potential of Metabotropic Glutamate Receptor Modulators
Hovelsø, N; Sotty, F; Montezinho, L.P; Pinheiro, P.S; Herrik, K.F; Mørk, A
2012-01-01
Glutamate is the main excitatory neurotransmitter in the central nervous system (CNS) and is a major player in complex brain functions. Glutamatergic transmission is primarily mediated by ionotropic glutamate receptors, which include NMDA, AMPA and kainate receptors. However, glutamate exerts modulatory actions through a family of metabotropic G-protein-coupled glutamate receptors (mGluRs). Dysfunctions of glutamatergic neurotransmission have been implicated in the etiology of several diseases. Therefore, pharmacological modulation of ionotropic glutamate receptors has been widely investigated as a potential therapeutic strategy for the treatment of several disorders associated with glutamatergic dysfunction. However, blockade of ionotropic glutamate receptors might be accompanied by severe side effects due to their vital role in many important physiological functions. A different strategy aimed at pharmacologically interfering with mGluR function has recently gained interest. Many subtype selective agonists and antagonists have been identified and widely used in preclinical studies as an attempt to elucidate the role of specific mGluRs subtypes in glutamatergic transmission. These studies have allowed linkage between specific subtypes and various physiological functions and more importantly to pathological states. This article reviews the currently available knowledge regarding the therapeutic potential of targeting mGluRs in the treatment of several CNS disorders, including schizophrenia, addiction, major depressive disorder and anxiety, Fragile X Syndrome, Parkinson’s disease, Alzheimer’s disease and pain. PMID:22942876
Zuriaga, María Angeles; Mas-Coma, Santiago; Bargues, María Dolores
2015-05-01
A pseudogene, designated as "ps(5.8S+ITS-2)", paralogous to the 5.8S gene and internal transcribed spacer (ITS)-2 of the nuclear ribosomal DNA (rDNA), has been recently found in many triatomine species distributed throughout North America, Central America and northern South America. Among characteristics used as criteria for pseudogene verification, secondary structures and free energy are highlighted, showing a lower fit between minimum free energy, partition function and centroid structures, although in given cases the fit only appeared to be slightly lower. The unique characteristics of "ps(5.8S+ITS-2)" as a processed or retrotransposed pseudogenic unit of the ghost type are reviewed, with emphasis on its potential functionality compared to the functionality of genes and spacers of the normal rDNA operon. Besides the technical problem of the risk for erroneous sequence results, the usefulness of "ps(5.8S+ITS-2)" for specimen classification, phylogenetic analyses and systematic/taxonomic studies should be highlighted, based on consistence and retention index values, which in pseudogenic sequence trees were higher than in functional sequence trees. Additionally, intraindividual, interpopulational and interspecific differences in pseudogene amount and the fact that it is a pseudogene in the nuclear rDNA suggests a potential relationships with fitness, behaviour and adaptability of triatomine vectors and consequently its potential utility in Chagas disease epidemiology and control.
Targeting complement-mediated immunoregulation for cancer immunotherapy.
Kolev, Martin; Markiewski, Maciej M
2018-06-01
Complement was initially discovered as an assembly of plasma proteins "complementing" the cytolytic activity of antibodies. However, our current knowledge places this complex system of several plasma proteins, receptors, and regulators in the center of innate immunity as a bridge between the initial innate responses and adaptive immune reactions. Consequently, complement appears to be pivotal for elimination of pathogens, not only as an early response defense, but by directing the subsequent adaptive immune response. The discovery of functional intracellular complement and its roles in cellular metabolism opened novel avenues for research and potential therapeutic implications. The recent studies demonstrating immunoregulatory functions of complement in the tumor microenvironment and the premetastatic niche shifted the paradigm on our understanding of functions of the complement system in regulating immunity. Several complement proteins, through their interaction with cells in the tumor microenvironment and in metastasis-targeted organs, contribute to modulating tumor growth, antitumor immunity, angiogenesis, and therefore, the overall progression of malignancy and, perhaps, responsiveness of cancer to different therapies. Here, we focus on recent progress in our understanding of immunostimulatory vs. immunoregulatory functions of complement and potential applications of these findings to the design of novel therapies for cancer patients. Copyright © 2018 Elsevier Ltd. All rights reserved.
To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes
Hoey, Andrew S.; Bellwood, David R.; Barnett, Adam
2012-01-01
Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes. PMID:22319124
Lathe, R
2001-05-01
Hippocampal lesions produce memory deficits, but the exact function of the hippocampus remains obscure. Evidence is presented that its role in memory may be ancillary to physiological regulation. Molecular studies demonstrate that the hippocampus is a primary target for ligands that reflect body physiology, including ion balance and blood pressure, immunity, pain, reproductive status, satiety and stress. Hippocampal receptors are functional, probably accessible to their ligands, and mediate physiological and cognitive changes. This argues that an early role of the hippocampus may have been in sensing soluble molecules (termed here 'enteroception') in blood and cerebrospinal fluid, perhaps reflecting a common evolutionary origin with the olfactory system ('exteroception'). Functionally, hippocampal enteroception may reflect feedback control; evidence is reviewed that the hippocampus modulates body physiology, including the activity of the hypothalamus-pituitary-adrenal axis, blood pressure, immunity, and reproductive function. It is suggested that the hippocampus operates, in parallel with the amygdala, to modulate body physiology in response to cognitive stimuli. Hippocampal outputs are predominantly inhibitory on downstream neuroendocrine activity; increased synaptic efficacy in the hippocampus (e.g. long-term potentiation) could facilitate throughput inhibition. This may have implications for the role of the hippocampus and long-term potentiation in memory.
To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes.
Hoey, Andrew S; Bellwood, David R; Barnett, Adam
2012-06-22
Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes.
Potential implications of the helical heart in congenital heart defects.
Corno, Antonio F; Kocica, Mladen J
2007-01-01
The anatomic and functional observations made by Francisco Torrent-Guasp, in particular his discovery of the helical ventricular myocardial band (HVMB), have challenged what has been taught to cardiologists and cardiac surgeons over centuries. A literature debate is ongoing, with interdependent articles and comments from supporters and critics. Adequate understanding of heart structure and function is obviously indispensable for the decision-making process in congenital heart defects. The HVMB described by Torrent-Guasp and the potential impact on the understanding and treatment of congenital heart defects has been analyzed in the following settings: embryology, ventriculo-arterial discordance (transposition of great arteries), Ebstein's anomaly, pulmonary valve regurgitation after repair of tetralogy of Fallot, Ross operation, and other congenital heart defects. The common structural spiral feature is only one of the elements responsible for the functional interaction of right and left ventricles, and understanding the form/function relationship in congenital heart defects is more difficult than for acquired heart disease because of the variety and complexity of congenital heart defects. Individuals involved in the care of patients with congenital heart defects have to be stimulated to consider further investigations and alternative surgical strategies.
Novel role of transient receptor potential vanilloid 2 in the regulation of cardiac performance
Lasko, Valerie M.; Koch, Sheryl E.; Singh, Vivek P.; Carreira, Vinicius; Robbins, Nathan; Patel, Amit R.; Jiang, Min; Bidwell, Philip; Kranias, Evangelia G.; Jones, W. Keith; Lorenz, John N.
2013-01-01
Transient receptor potential cation channels have been implicated in the regulation of cardiovascular function, but only recently has our laboratory described the vanilloid-2 subtype (TRPV2) in the cardiomyocyte, though its exact mechanism of action has not yet been established. This study tests the hypothesis that TRPV2 plays an important role in regulating myocyte contractility under physiological conditions. Therefore, we measured cardiac and vascular function in wild-type and TRPV2−/− mice in vitro and in vivo and found that TRPV2 deletion resulted in a decrease in basal systolic and diastolic function without affecting loading conditions or vascular tone. TRPV2 stimulation with probenecid, a relatively selective TRPV2 agonist, caused an increase in both inotropy and lusitropy in wild-type mice that was blunted in TRPV2−/− mice. We examined the mechanism of TRPV2 inotropy/lusitropy in isolated myocytes and found that it modulates Ca2+ transients and sarcoplasmic reticulum Ca2+ loading. We show that the activity of this channel is necessary for normal cardiac function and that there is increased contractility in response to agonism of TRPV2 with probenecid. PMID:24322617
Polyimine and its potential significance for prebiotic chemistry on Titan
NASA Astrophysics Data System (ADS)
Rahm, Martin; Lunine, Jonathan I.; Usher, David; Shalloway, David
2016-10-01
Hydrogen cyanide (HCN), a key reagent in prebiotic chemistry, is being generated in large amounts in the atmosphere of Titan. Contradictions between Cassini-Huygens measurements of the atmosphere and the surface of Titan, suggest that HCN is undergoing reaction chemistry, despite the frigid temperatures of 90-94 K. We will discuss computational results [1] investigating polyimine as one potential explanation for this observation. Polyimine is a polymer identified as the major component of polymerized HCN in laboratory experiments. It is flexible, which aids low temperature mobility, and it is able to form intermolecular and intramolecular =N-H...N hydrogen bonds, allowing for different polymorphs. Polymorphs have been predicted and explored by density functional theory coupled with a structure-searching algorithm. We have calculated the thermodynamics of polymerization, and show that polyimine is capable of absorbing light in a window of relative transparency in Titan's atmosphere. Light absorption and the possible catalytic functions of polyimine are suggestive of it driving photochemistry on the surface, with potential prebiotic implications.References:[1] M. Rahm, J. I. Lunine, D. Usher, D. Shalloway, "Polymorphism and electronic structure of polyimine and its potential significance for prebiotic chemistry on Titan", PNAS, early view. doi: 10.1073/pnas.1606634113
Brohi, Rahim Dad; Wang, Li; Hassine, Najla Ben; Cao, Jing; Talpur, Hira Sajjad; Wu, Di; Huang, Chun-Jie; Rehman, Zia-Ur; Bhattarai, Dinesh; Huo, Li-Jun
2017-01-01
Mature spermatozoa have highly condensed DNA that is essentially silent both transcriptionally and translationally. Therefore, post translational modifications are very important for regulating sperm motility, morphology, and for male fertility in general. Protein sumoylation was recently demonstrated in human and rodent spermatozoa, with potential consequences for sperm motility and DNA integrity. We examined the expression and localization of small ubiquitin-related modifier-1 (SUMO-1) in the sperm of water buffalo (Bubalus bubalis) using immunofluorescence analysis. We confirmed the expression of SUMO-1 in the acrosome. We further found that SUMO-1 was lost if the acrosome reaction was induced by calcium ionophore A23187. Proteins modified or conjugated by SUMO-1 in water buffalo sperm were pulled down and analyzed by mass spectrometry. Sixty proteins were identified, including proteins important for sperm morphology and motility, such as relaxin receptors and cytoskeletal proteins, including tubulin chains, actins, and dyneins. Forty-six proteins were predicted as potential sumoylation targets. The expression of SUMO-1 in the acrosome region of water buffalo sperm and the identification of potentially SUMOylated proteins important for sperm function implicates sumoylation as a crucial PTM related to sperm function. PMID:28659810
d'Aldin, C G; Ruel, J; Assié, R; Pujol, R; Puel, J L
1997-07-01
In the adult mammalian cochlea, the ability of nerve fibres to regenerate has been observed following disruption of the organ of Corti by various means, or transsection of the cochlear nerve in the internal auditory meatus. Based upon the implication of glutamate as a neurotransmitter at synapses between sensory hair cells and terminal dendrites of the auditory nerve in the mammalian cochlea, we have developed, in a previous study, an in vivo model of neural regeneration and formation of synapses after the destruction of the afferent nerve endings by local application of the glutamate agonist alpha-amino-3-hydroxy-5-methyl-isoxazol-propionic acid (AMPA). In situ hybridization experiments performed during the re-innervation process revealed an overexpression of mRNA coding for NR1 subunit of N-methyl-D-aspartate (NMDA) receptors in the spiral ganglion neurons, suggesting that these receptors are implicated in neural regenerative processes. The present study has been designed to study the functional implication of NMDA receptors in the regrowth and synaptic repair of auditory dendrites in the guinea pig cochlea, by blocking the NMDA receptors during the period of normal functional recovery. In a first set of experiments, we recorded compound action potential after acute perilymphatic perfusion of cumulative doses (0.03-10mM) of DL 2-amino-5-phosphonovalerate (D-AP5), a NMDA antagonist, to determine the efficiency of the drug. In a second set of experiments, the auditory dendrites were destroyed by local application of the glutamate agonist AMPA. The blockage of NMDA by the antagonist D-AP5 applied with an osmotic micropump delayed the functional recovery and the regrowth of auditory dendrites. The findings of our study support the hypothesis that, in addition to acting as a fast transmitter, glutamate has a neurotrophic role via the activation of NMDA receptors.
NASA Technical Reports Server (NTRS)
Mayo, L. H.
1971-01-01
A preliminary provisional assessment of the prospects for the establishment of an adequate technology assessment function and the implications of the assessment function for the public decision process are presented. Effects of the technology assessment function on each phase of the public decision process and briefly explored. Significant implications during the next decade are projected with respect to the following phases: invention and development of alternative means (technological configurations); evaluation, selection and promotion of preferred courses of action; and modification of statutory scheme or social action program as an outcome of continuing monitoring and appraisal.
HOTAIR: An Oncogenic Long Non-Coding RNA in Human Cancer.
Tang, Qing; Hann, Swei Sunny
2018-05-24
Long non-coding RNAs (LncRNAs) represent a novel class of noncoding RNAs that are longer than 200 nucleotides without protein-coding potential and function as novel master regulators in various human diseases, including cancer. Accumulating evidence shows that lncRNAs are dysregulated and implicated in various aspects of cellular homeostasis, such as proliferation, apoptosis, mobility, invasion, metastasis, chromatin remodeling, gene transcription, and post-transcriptional processing. However, the mechanisms by which lncRNAs regulate various biological functions in human diseases have yet to be determined. HOX antisense intergenic RNA (HOTAIR) is a recently discovered lncRNA and plays a critical role in various areas of cancer, such as proliferation, survival, migration, drug resistance, and genomic stability. In this review, we briefly introduce the concept, identification, and biological functions of HOTAIR. We then describe the involvement of HOTAIR that has been associated with tumorigenesis, growth, invasion, cancer stem cell differentiation, metastasis, and drug resistance in cancer. We also discuss emerging insights into the role of HOTAIR as potential biomarkers and therapeutic targets for novel treatment paradigms in cancer. © 2018 The Author(s). Published by S. Karger AG, Basel.
The ortholog of the human proto-oncogene ROS1 is required for epithelial development in C. elegans
Jones, Martin R; Rose, Ann M; Baillie, David L
2013-01-01
The orphan receptor ROS1 is a human proto-oncogene, mutations of which are found in an increasing number of cancers. Little is known about the role of ROS1, however in vertebrates it has been implicated in promoting differentiation programs in specialized epithelial tissues. In this study we show that the C. elegans ortholog of ROS1, the receptor tyrosine kinase ROL-3, has an essential role in orchestrating the morphogenesis and development of specialized epidermal tissues, highlighting a potentially conserved function in coordinating crosstalk between developing epithelial cells. We also provide evidence of a direct relationship between ROL-3, the mucin SRAP-1, and BCC-1, the homolog of mRNA regulating protein Bicaudal-C. This study answers a longstanding question as to the developmental function of ROL-3, identifies three new genes that are expressed and function in the developing epithelium of C. elegans, and introduces the nematode as a potentially powerful model system for investigating the increasingly important, yet poorly understood, human oncogene ROS1. genesis 51:545–561. PMID:23733356
Li, Yuan; Li, Jiagen; Luo, Mei; Zhou, Chengcheng; Shi, Xuejiao; Yang, Wenhui; Lu, Zhiliang; Chen, Zhaoli; Sun, Nan; He, Jie
2018-05-12
Long noncoding RNAs (lncRNA) have been implicated in cancer but most of them remain largely unstudied. Here, we identified a novel NSUN2 methylated lncRNA (NMR), which was significantly upregulated in esophageal squamous cell carcinoma (ESCC), functioned as a key regulator of ESCC tumor metastasis and drug resistance. Upregulation of NMR correlated with tumor metastasis and indicated poor overall survival in ESCC patients. Functionally, NMR could promote tumor cell migration and invasion, inhibit cisplatin-induced apoptosis and increase drug resistance in ESCC cells. Mechanistically, transcription of NMR could be upregulated by NF-κB activation after IL-1β and TNF-α treatment. NMR was methylated by NSUN2 and might competitively inhibit methylation of potential mRNAs. NMR could directly bind to chromatin regulator BPTF, and potentially promote MMP3 and MMP10 expression by ERK1/2 pathway through recruiting BPTF to chromatin. Taken together, NMR functions as an oncogenic gene and may serve as new biomarker and therapeutic target in ESCC. Copyright © 2018 Elsevier B.V. All rights reserved.
GPR 120: The Potential Target for Obesity Treatment.
Tanagho, Peter A; Shohdy, Kyrillus S
2016-01-01
G protein coupled receptor 120 (GPR120) is a class of receptors in the gastrointestinal tract (GIT) that is implicated in nutrient sensing and body weight regulation. Functions of GPR120 are thought to be mediated by the release of a group of hormones known as incretins, such as glucagon like peptide 1 (GLP-1) and gastric inhibitory polypeptide (GIP). We have searched PubMed with the keywords "GPR120","GLP-1" and "obesity". Relevant studies were retrieved and included in the review. Recently, many exogenous compounds have been investigated in their role in the release of GLP-1 and in causing weight loss in obese rats. However, some results question the putative role of GPR120 in metabolic homeostasis. Herein, we evaluate the potential use of GPR120 as a target receptor in obesity and found it to be ubiquitous throughout the GIT, with various functions in each site. In order to find the optimal drug, the role of GPR120 in each site needs to be defined and selectivity of the potential drug needs to be studied to ensure the success of this growing line of obesity management.
Krzyzanowska, Agnieszka; Carro, Eva
2012-01-01
Morphological alterations of choroid plexus in Alzheimer's disease (AD) have been extensively investigated. These changes include epithelial atrophy, thickening of the basement membrane, and stroma fibrosis. As a result, synthesis, secretory, and transportation functions are significantly altered resulting in decreased cerebrospinal fluid (CSF) turnover. Recent studies discuss the potential impacts of these changes, including the possibility of reduced resistance to stress insults and slow clearance of toxic compounds from CSF with specific reference to the amyloid peptide. Here, we review new evidences for AD-related changes in the choroid plexus. The data suggest that the significantly altered functions of the choroid plexus contribute to the multiparametric pathogenesis of late-onset AD.
NMDA receptor dysfunction in autism spectrum disorders.
Lee, Eun-Jae; Choi, Su Yeon; Kim, Eunjoon
2015-02-01
Abnormalities and imbalances in neuronal excitatory and inhibitory synapses have been implicated in diverse neuropsychiatric disorders including autism spectrum disorders (ASDs). Increasing evidence indicates that dysfunction of NMDA receptors (NMDARs) at excitatory synapses is associated with ASDs. In support of this, human ASD-associated genetic variations are found in genes encoding NMDAR subunits. Pharmacological enhancement or suppression of NMDAR function ameliorates ASD symptoms in humans. Animal models of ASD display bidirectional NMDAR dysfunction, and correcting this deficit rescues ASD-like behaviors. These findings suggest that deviation of NMDAR function in either direction contributes to the development of ASDs, and that correcting NMDAR dysfunction has therapeutic potential for ASDs. Copyright © 2014 Elsevier Ltd. All rights reserved.
Harnessing dendritic cells in inflammatory skin diseases
Chu, Chung-Ching; Di Meglio, Paola; Nestle, Frank O.
2011-01-01
The skin immune system harbors a complex network of dendritic cells (DCs). Recent studies highlight a diverse functional specialization of skin DC subsets. In addition to generating cellular and humoral immunity against pathogens, skin DCs are involved in tolerogenic mechanisms to ensure the maintenance of immune homeostasis, as well as in pathogenesis of chronic inflammation in the skin when excessive immune responses are initiated and unrestrained. Harnessing DCs by directly targeting DC-derived molecules or selectively modulate DC subsets is a convincing strategy to tackle inflammatory skin diseases. In this review we discuss recent advances underlining the functional specialization of skin DCs and discuss the potential implication for future DC-based therapeutic strategies. PMID:21295490
Myeloid-derived suppressor cells modulate B-cell responses.
Lelis, Felipe J N; Jaufmann, Jennifer; Singh, Anurag; Fromm, Katja; Teschner, Annkathrin Chiara; Pöschel, Simone; Schäfer, Iris; Beer-Hammer, Sandra; Rieber, Nikolaus; Hartl, Dominik
2017-08-01
Myeloid-derived suppressor cells (MDSCs) are key regulators of adaptive immunity by suppressing T-cell functions. However, their potential action on or interaction with B cells remained poorly understood. Here we demonstrate that human polymorphonuclear MDSCs differentially modulate B-cell function by suppressing B-cell proliferation and antibody production. We further demonstrate that this MDSC-mediated effect is cell contact dependent and involves established mediators such as arginase-1, nitric oxide (NO), reactive oxygen species (ROS) as well as B-cell death. Collectively, our studies provide novel evidence that human MDSCs modulate B cells, which could have future implications for immunotherapy approaches. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.
Non-coding RNA networks underlying cognitive disorders across the lifespan
Qureshi, Irfan A.; Mehler, Mark F.
2011-01-01
Non-coding RNAs (ncRNAs) and their associated regulatory networks are increasingly being implicated in mediating a complex repertoire of neurobiological functions. Cognitive and behavioral processes are proving to be no exception. Here, we discuss the emergence of many novel, diverse, and rapidly expanding classes and subclasses of short and long ncRNAs. We briefly review the life cycles and molecular functions of these ncRNAs. We also examine how ncRNA circuitry mediates brain development, plasticity, stress responses, and aging and highlight its potential roles in the pathophysiology of cognitive disorders, including neural developmental and age-associated neurodegenerative diseases as well as those that manifest throughout the lifespan. PMID:21411369
Melatonin and Hippo Pathway: Is There Existing Cross-Talk?
Lo Sardo, Federica; Muti, Paola; Blandino, Giovanni; Strano, Sabrina
2017-09-06
Melatonin is an indolic hormone that regulates a plethora of functions ranging from the regulation of circadian rhythms and antioxidant properties to the induction and maintenance of tumor suppressor pathways. It binds to specific receptors as well as to some cytosolic proteins, leading to several cellular signaling cascades. Recently, the involvement of melatonin in cancer insurgence and progression has clearly been demonstrated. In this review, we will first describe the structure and functions of melatonin and its receptors, and then discuss both molecular and epidemiological evidence on melatonin anticancer effects. Finally, we will shed light on potential cross-talk between melatonin signaling and the Hippo signaling pathway, along with the possible implications for cancer therapy.
Using Technology to Facilitate Collaboration in Community-Based Participatory Research (CBPR)
Jessell, Lauren; Smith, Vivian; Jemal, Alexis; Windsor, Liliane
2017-01-01
This study explores the use of Computer-Supported Collaborative Work (CSCW) technologies, by way of a computer-based system called iCohere. This system was used to facilitate collaboration conducting Community-Based Participatory Research (CBPR). Data was gathered from 13 members of a Community Collaborative Board (CCB). Analysis revealed that iCohere served the following functions: facilitating communication, providing a depository for information and resource sharing, and allowing for remote meeting attendance. Results indicated that while iCohere was useful in performing these functions, less expensive technologies had the potential to achieve similar goals if properly implemented. Implications for future research on CSCW systems and CBPR are discussed. PMID:29056871
Lim, Jia Pei; Devaux, Jérôme; Yuki, Nobuhiro
2014-10-01
Guillain-Barré syndrome is classified into acute inflammatory demyelinating polyneuropathy and acute motor axonal neuropathy. Whereas autoantibodies to GM1 or GD1a induce the development of acute motor axonal neuropathy, pathogenic autoantibodies have yet to be identified in acute inflammatory demyelinating polyneuropathy and chronic inflammatory demyelinating polyneuropathy. This review highlights the importance of autoantibodies to peripheral nerve proteins in the physiopathology of acute and chronic inflammatory demyelinating polyneuropathies. Moreover, we listed up other potential antigens, which may become helpful biomarkers for acquired, dysimmune demyelinating neuropathies based on their critical functions during myelination and their implications in hereditary demyelinating neuropathies. Copyright © 2014 Elsevier B.V. All rights reserved.
An auditory-neuroscience perspective on the development of selective mutism.
Henkin, Yael; Bar-Haim, Yair
2015-04-01
Selective mutism (SM) is a relatively rare psychiatric disorder of childhood characterized by consistent inability to speak in specific social situations despite the ability to speak normally in others. SM typically involves severe impairments in social and academic functioning. Common complications include school failure, social difficulties in the peer group, and aggravated intra-familial relationships. Although SM has been described in the medical and psychological literatures for many years, the potential underlying neural basis of the disorder has only recently been explored. Here we explore the potential role of specific auditory neural mechanisms in the psychopathology of SM and discuss possible implications for treatment. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.
Parto, Parham; Lavie, Carl J; Arena, Ross; Bond, Samantha; Popovic, Dejana; Ventura, Hector O
2016-11-01
The prevalence of obesity among adults and children worldwide has reached epic proportions and has become a major independent risk factor for the development of heart failure (HF), in addition to a contributor of hypertension and cardiovascular disease. The implications of obesity in the development of HF involve adverse effects on cardiac structure and function. Despite all of this, in the setting of chronic HF, excess body mass is associated with improved clinical outcomes, demonstrating the presence of an obesity paradox. In this review, we will discuss the gender differences, global application, potential mechanisms and role of interventions based on fitness and purposeful weight loss as potential therapeutic strategies.
Why do depressed individuals have difficulties in their parenting role?
Psychogiou, L; Parry, E
2014-05-01
Although existing research has shown that depression in parents has a negative effect on parent-child interactions, the mechanisms underpinning impaired parenting are still unknown. In this editorial, we review core difficulties that have been noted in depressed individuals including reduced positive and increased negative affect, poor emotion regulation, executive function deficits, reduced motivation and rumination, and discuss how each of these can alter parenting. We suggest that these causal processes are inter-related and can interact with one another in affecting parenting. We conclude that an improved understanding of these processes will have implications for the development of more specific and potentially more effective treatments that have the potential to break the intergenerational transmission of psychopathology.
Brassard, Audrey; Dupuy, Emmanuelle; Bergeron, Sophie; Shaver, Phillip R
2015-01-01
We examined the potential role of three mediators--sexual self-esteem, sexual anxiety, and sexual assertiveness--of the association between romantic attachment insecurities (anxiety and avoidance) and two aspects of women's sexual functioning: sexual function and sexual satisfaction. A sample of 556 women aged 18 to 30 agreed to complete an online series of validated questionnaires assessing attachment insecurities and several aspects of sexual functioning. Lower sexual self-esteem and higher sexual anxiety mediated the associations between attachment anxiety and lower sexual function and satisfaction. Lower sexual self-esteem and higher sexual anxiety also partially mediated the links between attachment-related avoidance and the two sexual functioning variables. Sexual assertiveness, however, did not mediate these associations. A significant interaction between attachment anxiety and avoidance was also found to predict sexual satisfaction, with women high in avoidance and low in anxiety being the least satisfied. Results are discussed in terms of theoretical and clinical implications.
Composition and work function relationship in Os–Ru–W ternary alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Swartzentruber, Phillip D.; Detisch, Michael J.; Balk, T. John, E-mail: john.balk@uky.edu
2015-03-15
Os–Ru thin films with varying concentrations of W were sputter deposited in order to investigate their structure–property relationships. The films were analyzed with x-ray diffraction to investigate their crystal structures, and a Kelvin probe to investigate their work functions. An Os–Ru–W film with ∼30 at. % W yielded a work function maximum of approximately 5.38 eV. These results align well with other studies that found work function minima from thermionic emission data on M-type cathodes with varying amounts of W in the coatings. Furthermore, the results are consistent with other work explaining energy-level alignment and charge transfer of molecules on metalmore » oxides. This may shed light on the mechanism behind the “anomalous effect” first reported by Zalm et al., whereby a high work function coating results in a low work function for emitting cathode surfaces. An important implication of this work is the potential for the Kelvin probe to evaluate the effectiveness of dispenser cathode coatings.« less
Glutamate Receptor Homologs in Plants: Functions and Evolutionary Origins
Price, Michelle Beth; Jelesko, John; Okumoto, Sakiko
2012-01-01
The plant glutamate-like receptor homologs (GLRs) are homologs of mammalian ionotropic glutamate receptors (iGluRs) which were discovered more than 10 years ago, and are hypothesized to be potential amino acid sensors in plants. Although initial progress on this gene family has been hampered by gene redundancy and technical issues such as gene toxicity; genetic, pharmacological, and electrophysiological approaches are starting to uncover the functions of this protein family. In parallel, there has been tremendous progress in elucidating the structure of animal glutamate receptors (iGluRs), which in turn will help understanding of the molecular mechanisms of plant GLR functions. In this review, we will summarize recent progress on the plant GLRs. Emerging evidence implicates plant GLRs in various biological processes in and beyond N sensing, and implies that there is some overlap in the signaling mechanisms of amino acids between plants and animals. Phylogenetic analysis using iGluRs from metazoans, plants, and bacteria showed that the plant GLRs are no more closely related to metazoan iGluRs as they are to bacterial iGluRs, indicating the separation of plant, other eukaryotic, and bacterial GLRs might have happened as early on as the last universal common ancestor. Structural similarities and differences with animal iGluRs, and the implication thereof, are also discussed. PMID:23115559
Longo, Liam; Lee, Jihun; Blaber, Michael
2012-12-01
The acquisition of function is often associated with destabilizing mutations, giving rise to the stability-function tradeoff hypothesis. To test whether function is also accommodated at the expense of foldability, fibroblast growth factor-1 (FGF-1) was subjected to a comprehensive φ-value analysis at each of the 11 turn regions. FGF-1, a β-trefoil fold, represents an excellent model system with which to evaluate the influence of function on foldability: because of its threefold symmetric structure, analysis of FGF-1 allows for direct comparisons between symmetry-related regions of the protein that are associated with function to those that are not; thus, a structural basis for regions of foldability can potentially be identified. The resulting φ-value distribution of FGF-1 is highly polarized, with the majority of positions described as either folded-like or denatured-like in the folding transition state. Regions important for folding are shown to be asymmetrically distributed within the protein architecture; furthermore, regions associated with function (i.e., heparin-binding affinity and receptor-binding affinity) are localized to regions of the protein that fold after barrier crossing (late in the folding pathway). These results provide experimental support for the foldability-function tradeoff hypothesis in the evolution of FGF-1. Notably, the results identify the potential for folding redundancy in symmetric protein architecture with important implications for protein evolution and design. Copyright © 2012 The Protein Society.
NASA Astrophysics Data System (ADS)
Mejia-Rodriguez, Daniel; Trickey, S. B.
2017-11-01
We explore the simplification of widely used meta-generalized-gradient approximation (mGGA) exchange-correlation functionals to the Laplacian level of refinement by use of approximate kinetic-energy density functionals (KEDFs). Such deorbitalization is motivated by the prospect of reducing computational cost while recovering a strictly Kohn-Sham local potential framework (rather than the usual generalized Kohn-Sham treatment of mGGAs). A KEDF that has been rather successful in solid simulations proves to be inadequate for deorbitalization, but we produce other forms which, with parametrization to Kohn-Sham results (not experimental data) on a small training set, yield rather good results on standard molecular test sets when used to deorbitalize the meta-GGA made very simple, Tao-Perdew-Staroverov-Scuseria, and strongly constrained and appropriately normed functionals. We also study the difference between high-fidelity and best-performing deorbitalizations and discuss possible implications for use in ab initio molecular dynamics simulations of complicated condensed phase systems.
The sacroiliac joint: an overview of its anatomy, function and potential clinical implications
Vleeming, A; Schuenke, M D; Masi, A T; Carreiro, J E; Danneels, L; Willard, F H
2012-01-01
This article focuses on the (functional) anatomy and biomechanics of the pelvic girdle and specifically the sacroiliac joints (SIJs). The SIJs are essential for effective load transfer between the spine and legs. The sacrum, pelvis and spine, and the connections to the arms, legs and head, are functionally interrelated through muscular, fascial and ligamentous interconnections. A historical overview is presented on pelvic and especially SIJ research, followed by a general functional anatomical overview of the pelvis. In specific sections, the development and maturation of the SIJ is discussed, and a description of the bony anatomy and sexual morphism of the pelvis and SIJ is debated. The literature on the SIJ ligaments and innervation is discussed, followed by a section on the pathology of the SIJ. Pelvic movement studies are investigated and biomechanical models for SIJ stability analyzed, including examples of insufficient versus excessive sacroiliac force closure. PMID:22994881
Duménieu, Maël; Oulé, Marie; Kreutz, Michael R.; Lopez-Rojas, Jeffrey
2017-01-01
Neurons are highly polarized cells with apparent functional and morphological differences between dendrites and axon. A critical determinant for the molecular and functional identity of axonal and dendritic segments is the restricted expression of voltage-gated ion channels (VGCs). Several studies show an uneven distribution of ion channels and their differential regulation within dendrites and axons, which is a prerequisite for an appropriate integration of synaptic inputs and the generation of adequate action potential (AP) firing patterns. This review article will focus on the signaling pathways leading to segmented expression of voltage-gated potassium and sodium ion channels at the neuronal plasma membrane and the regulatory mechanisms ensuring segregated functions. We will also discuss the relevance of proper ion channel targeting for neuronal physiology and how alterations in polarized distribution contribute to neuronal pathology. PMID:28484374
Wagner, Karoline; Besemer, Katharina; Burns, Nancy R.; Battin, Tom J.
2015-01-01
Summary Changes in riparian vegetation or water turbidity and browning in streams alter the local light regime with potential implications for stream biofilms and ecosystem functioning. We experimented with biofilms in microcosms grown under a gradient of light intensities (range: 5–152 μmole photons s−1 m−2) and combined 454‐pyrosequencing and enzymatic activity assays to evaluate the effects of light on biofilm structure and function. We observed a shift in bacterial community composition along the light gradient, whereas there was no apparent change in alpha diversity. Multifunctionality, based on extracellular enzymes, was highest under high light conditions and decoupled from bacterial diversity. Phenol oxidase activity, involved in the degradation of polyphenolic compounds, was twice as high on average under the lowest compared with the highest light condition. This suggests a shift in reliance of microbial heterotrophs on biofilm phototroph‐derived organic matter under high light availability to more complex organic matter under low light. Furthermore, extracellular enzyme activities correlated with nutrient cycling and community respiration, supporting the link between biofilm structure–function and biogeochemical fluxes in streams. Our findings demonstrate that changes in light availability are likely to have significant impacts on biofilm structure and function, potentially affecting stream ecosystem processes. PMID:26013911
Potential oil spill risk from shipping and the implications for management in the Caribbean Sea.
Singh, Asha; Asmath, Hamish; Chee, Candice Leung; Darsan, Junior
2015-04-15
The semi enclosed Caribbean Sea is ranked as having one of the most intense maritime traffic in the world. These maritime activities have led to significant oil pollution. Simultaneously, this sea supports many critical habitats functioning as a Large Marine Ecosystem (LME). While the impacts of oil pollution are recognised, a number of management challenges remain. This study applies spatial modelling to identify critical areas potentially at risk from oil spills in the form of a potential oil spill risk (POSR) model. The model indicates that approximately 83% of the sea could be potentially impacted by oil spills due to shipping. The results from this study collectively support a management framework for minimising ship generated oil pollution in the Caribbean Sea. Among the recommended components are a common policy, surveillance and monitoring controls, standards, monitoring programmes, data collection and greater rates of convention ratifications. Copyright © 2015 Elsevier Ltd. All rights reserved.
Li, Yan; Wang, Wei; Lv, Zhe; Li, Yun; Chen, Yan; Huang, Kewu; Corrigan, Chris J; Ying, Sun
2018-04-01
The epithelial cytokines IL-33, thymic stromal lymphopoietin (TSLP), and IL-25 have been implicated in asthma pathogenesis because they promote Th2-type cytokine synthesis, but their expression is relatively poorly documented in "real-life" human asthma. Using bronchoalveolar lavage fluid (BALF), we measured airway concentrations of these mediators and compared them with those of Th1- and Th2-type cytokines, airway infiltration of neutrophils and eosinophils, and lung function in a large group of asthmatic patients with a range of disease severity ( n = 70) and control subjects ( n = 30). The median BALF concentrations of IL-33, TSLP, IL-4, IL-5, IL-13, and IL-12p70, but not IL-25, IL-2, or IFN-γ, were significantly elevated in asthmatics compared with controls ( p < 0.05). The concentrations of IL-33 and TSLP, but not IL-25, correlated inversely with the lung function (forced expiratory volume in the first second) of asthmatics (IL-33: r = -0.488, p < 0.0001; TSLP: r = -0.565, p < 0.0001) independently of corticosteroid therapy. When divided according to disease severity and corticosteroid therapy, all subgroups of asthmatics had elevated median numbers of eosinophils in BALF, whereas the patients with more severe disease who were treated with corticosteroids had higher numbers of neutrophils compared with milder asthmatics not so treated and control subjects ( p < 0.05). The data implicate TSLP and IL-33 in the pathogenesis of asthma that is characterized by persistent airway inflammation and impaired lung function despite intensive corticosteroid therapy, highlighting them as potential molecular targets. Copyright © 2018 by The American Association of Immunologists, Inc.
Prouty, Eric W; Chandler, Daniel J; Waterhouse, Barry D
2017-11-15
Serotonin (5-HT)-containing neurons in the dorsal raphe (DR) nucleus project throughout the forebrain and are implicated in many physiological processes and neuropsychiatric disorders. Diversity among these neurons has been characterized in terms of their neurochemistry and anatomical organization, but a clear sense of whether these attributes align with specific brain functions or terminal fields is lacking. DR 5-HT neurons can co-express additional neuroactive substances, increasing the potential for individualized regulation of target circuits. The goal of this study was to link DR neurons to a specific functional role by characterizing cells according to both their neurotransmitter expression and efferent connectivity; specifically, cells projecting to the medial prefrontal cortex (mPFC), a region implicated in cognition, emotion, and responses to stress. Following retrograde tracer injection, brainstem sections from Sprague-Dawley rats were immunohistochemically stained for markers of serotonin, glutamate, GABA, and nitric oxide (NO). 98% of the mPFC-projecting serotonergic neurons co-expressed the marker for glutamate, while the markers for NO and GABA were observed in 60% and less than 1% of those neurons, respectively. To identify potential target-specific differences in co-transmitter expression, we also characterized DR neurons projecting to a visual sensory structure, the lateral geniculate nucleus (LGN). The proportion of serotonergic neurons co-expressing NO was greater amongst cells targeting the mPFC vs LGN (60% vs 22%). The established role of 5-HT in affective disorders and the emerging role of NO in stress signaling suggest that the impact of 5-HT/NO co-localization in DR neurons that regulate mPFC circuit function may be clinically relevant. Copyright © 2017 Elsevier B.V. All rights reserved.
Ibarguren, Maitane; López, David J; Escribá, Pablo V
2014-06-01
This review deals with the effects of synthetic and natural fatty acids on the biophysical properties of membranes, and on their implication on cell function. Natural fatty acids are constituents of more complex lipids, like triacylglycerides or phospholipids, which are used by cells to store and obtain energy, as well as for structural purposes. Accordingly, natural and synthetic fatty acids may modify the structure of the lipid membrane, altering its microdomain organization and other physical properties, and provoking changes in cell signaling. Therefore, by modulating fatty acids it is possible to regulate the structure of the membrane, influencing the cell processes that are reliant on this structure and potentially reverting pathological cell dysfunctions that may provoke cancer, diabetes, hypertension, Alzheimer's and Parkinson's disease. The so-called Membrane Lipid Therapy offers a strategy to regulate the membrane composition through drug administration, potentially reverting pathological processes by re-adapting cell membrane structure. Certain fatty acids and their synthetic derivatives are described here that may potentially be used in such therapies, where the cell membrane itself can be considered as a target to combat disease. This article is part of a Special Issue entitled: Membrane Structure and Function: Relevance in the Cell's Physiology, Pathology and Therapy. Copyright © 2013 Elsevier B.V. All rights reserved.
Primary cilia: cellular sensors for the skeleton.
Anderson, Charles T; Castillo, Alesha B; Brugmann, Samantha A; Helms, Jill A; Jacobs, Christopher R; Stearns, Tim
2008-09-01
The primary cilium is a solitary, immotile cilium that is present in almost every mammalian cell type. Primary cilia are thought to function as chemosensors, mechanosensors, or both, depending on cell type, and have been linked to several developmental signaling pathways. Primary cilium malfunction has been implicated in several human diseases, the symptoms of which include vision and hearing loss, polydactyly, and polycystic kidneys. Recently, primary cilia have also been implicated in the development and homeostasis of the skeleton. In this review, we discuss the structure and formation of the primary cilium and some of the mechanical and chemical signals to which it could be sensitive, with a focus on skeletal biology. We also raise several unanswered questions regarding the role of primary cilia as mechanosensors and chemosensors and identify potential research avenues to address these questions.
Primary Cilia: Cellular Sensors for the Skeleton
Anderson, Charles T.; Castillo, Alesha B.; Brugmann, Samantha A.; Helms, Jill A.; Jacobs, Christopher R.; Stearns, Tim
2010-01-01
The primary cilium is a solitary, immotile cilium that is present in almost every mammalian cell type. Primary cilia are thought to function as chemosensors, mechanosensors, or both, depending on cell type, and have been linked to several developmental signaling pathways. Primary cilium malfunction has been implicated in several human diseases, the symptoms of which include vision and hearing loss, polydactyly, and polycystic kidneys. Recently, primary cilia have also been implicated in the development and homeostasis of the skeleton. In this review, we discuss the structure and formation of the primary cilium and some of the mechanical and chemical signals to which it could be sensitive, with a focus on skeletal biology. We also raise several unanswered questions regarding the role of primary cilia as mechanosensors and chemosensors and identify potential research avenues to address these questions. PMID:18727074
Violence against teachers: prevalence and consequences.
Wilson, Catherine M; Douglas, Kevin S; Lyon, David R
2011-08-01
Data collected from 731 teachers were used to examine the consequences of violence directed toward teachers while in the workplace. Analyses showed that the majority of respondents (n = 585, 80.0%) had experienced school-related violence—broadly defined—at one point in their careers. Serious violence (actual, attempted, or threatened physical violence) was less common, but still common enough to be of concern (n = 202, 27.6%). Violence predicted physical and emotional effects, as well as teaching-related functioning. In addition, a model with fear as a potential mediator revealed that both fear and violence were independently predictive of these negative outcomes. Finally, analyses showed that, in general, women reported higher levels of physical symptoms compared to men. We discuss the implications of violence against teachers in terms of personal consequences and the implications for mental health professionals working in an educational setting.
Ras signaling in aging and metabolic regulation.
Slack, Cathy
2017-12-07
Aberrant signal transduction downstream of the Ras GTPase has a well-established role in tumorigenesis. Mutations that result in hyperactivation of Ras are responsible for a third of all human cancers. Hence, small molecule inhibitors of the Ras signal transduction cascade have been under intense focus as potential cancer treatments. In both invertebrate and mammalian models, emerging evidence has also implicated components of the Ras signaling pathway in aging and metabolic regulation. Here, I review the current evidence for Ras signaling in these newly discovered roles highlighting the interactions between the Ras pathway and other longevity assurance mechanisms. Defining the role of Ras signaling in maintaining age-related health may have important implications for the development of interventions that could not only increase lifespan but also delay the onset and/or progression of age-related functional decline.
NASA Astrophysics Data System (ADS)
Bresehars, D. D.; Myers, O. B.; Barnes, F. J.
2003-12-01
Woody plant encroachment in dryland ecosystems is an issue of global concern, yet mechanisms related to encroachment are poorly understood. Mechanisms associated with woody plant encroachment likely relate to soil water dynamics, yet few long-term data sets exist to evaluate soil water heterogeneity. Here we highlight how soil water varies both temporally (wet vs. dry years and snow vs. rain dominated months) and spatially (vertically with depth and horizontally beneath vs. between the canopies of woody plants). We measured soil water content using neutron probe over a 15-year period in a pinyon-juniper woodland at the Mesita del Buey Research Site in northern New Mexico. Our objectives included assessing (1) the temporal variability of soil water, both as a function of depth and as a function of cover (canopy patches beneath trees, intercanopy patches between trees, and edges between the two patch types); and (2) implications for the vertical and horizontal distributions of plant-available water. Our results highlight (1) large temporal variations in soil water availability, driven largely by differences in winter precipitation, and (2) the potential importance of considering horizontal as well as vertical heterogeneity in soil moisture. The spatio-temporal variation in soil water that we quantify highlights the potential complexity of changes in the water budget that could be associated with woody plant encroachment and emphasizes the importance of considering horizontal as well as vertical heterogeneity in soil water in improving our understanding of mechanisms associated with woody plant encroachment.
Scioli-Salter, Erica R; Forman, Daniel E; Otis, John D; Gregor, Kristin; Valovski, Ivan; Rasmusson, Ann M
2015-04-01
Chronic pain and posttraumatic stress disorder (PTSD) are disabling conditions that affect biological, psychological, and social domains of functioning. Clinical research demonstrates that patients who are affected by chronic pain and PTSD in combination experience greater pain, affective distress, and disability than patients with either condition alone. Additional research is needed to delineate the interrelated pathophysiology of chronic pain and PTSD, with the goal of facilitating more effective therapies to treat both conditions more effectively; current treatment strategies for chronic pain associated with PTSD have limited efficacy and place a heavy burden on patients, who must visit various specialists to manage these conditions separately. This article focuses on neurobiological factors that may contribute to the coprevalence and synergistic interactions of chronic pain and PTSD. First, we outline how circuits that mediate emotional distress and physiological threat, including pain, converge. Secondly, we discuss specific neurobiological mediators and modulators of these circuits that may contribute to chronic pain and PTSD symptoms. For example, neuropeptide Y, and the neuroactive steroids allopregnanolone and pregnanolone (together termed ALLO) have antistress and antinociceptive properties. Reduced levels of neuropeptide Y and ALLO have been implicated in the pathophysiology of both chronic pain and PTSD. The potential contribution of opioid and cannabinoid system factors also will be discussed. Finally, we address potential novel methods to restore the normal function of these systems. Such novel perspectives regarding disease and disease management are vital to the pursuit of relief for the many individuals who struggle with these disabling conditions.
Jin, Yulan; Sharma, Ashok; Bai, Shan; Davis, Colleen; Liu, Haitao; Hopkins, Diane; Barriga, Kathy; Rewers, Marian; She, Jin-Xiong
2014-07-01
There is tremendous scientific and clinical value to further improving the predictive power of autoantibodies because autoantibody-positive (AbP) children have heterogeneous rates of progression to clinical diabetes. This study explored the potential of gene expression profiles as biomarkers for risk stratification among 104 AbP subjects from the Diabetes Autoimmunity Study in the Young (DAISY) using a discovery data set based on microarray and a validation data set based on real-time RT-PCR. The microarray data identified 454 candidate genes with expression levels associated with various type 1 diabetes (T1D) progression rates. RT-PCR analyses of the top-27 candidate genes confirmed 5 genes (BACH2, IGLL3, EIF3A, CDC20, and TXNDC5) associated with differential progression and implicated in lymphocyte activation and function. Multivariate analyses of these five genes in the discovery and validation data sets identified and confirmed four multigene models (BI, ICE, BICE, and BITE, with each letter representing a gene) that consistently stratify high- and low-risk subsets of AbP subjects with hazard ratios >6 (P < 0.01). The results suggest that these genes may be involved in T1D pathogenesis and potentially serve as excellent gene expression biomarkers to predict the risk of progression to clinical diabetes for AbP subjects. © 2014 by the American Diabetes Association.
Long Noncoding RNAs and Cardiac Disease.
Greco, Simona; Salgado Somoza, Antonio; Devaux, Yvan; Martelli, Fabio
2017-08-30
To maintain homeostasis, gene expression has to be tightly regulated by complex and multiple mechanisms occurring at the epigenetic, transcriptional, and post-transcriptional levels. One crucial regulatory component is represented by long noncoding RNAs (lncRNAs), nonprotein-coding RNA species implicated in all of these levels. Thus, lncRNAs have been associated with any given process or pathway of interest in a variety of systems, including the heart. Recent Advances: Mounting evidence implicates lncRNAs in cardiovascular diseases (CVD) and progression and their presence in the blood of heart disease patients indicates that they are attractive potential biomarkers. Our understanding of the regulation and molecular mechanisms of action of most lncRNAs remains rudimentary. A challenge is represented by their often low evolutionary sequence conservation that limits the use of animal models for preclinical studies. Nevertheless, a growing number of lncRNAs with an impact on heart function is rapidly accumulating. In this study, we will discuss (a) lncRNAs that control heart homeostasis and disease; (b) concepts, approaches, and methodologies necessary to study lncRNAs in the heart; and (c) challenges posed and opportunities presented by lncRNAs as potential therapeutic targets and biomarkers. A deeper knowledge of the molecular mechanisms underpinning CVDs is necessary to develop more effective treatments. Further studies are needed to clarify the regulation and function of lncRNAs in the heart before they can be considered as therapeutic targets and disease biomarkers. Antioxid. Redox Signal. 00, 000-000.
Peng, Hui; Bian, Xi-Ling; Ma, Fu-Cui; Wang, Ke-Wei
2017-09-01
The prefrontal cortex (PFC) critical for higher cognition is implicated in neuropsychiatric diseases, such as Alzheimer's disease, depression and schizophrenia. The voltage-activated Kv7/KCNQ/M-channel or M-current modulates the neuronal excitability that defines the fundamental mechanism of brain function. However, whether M-current functions to regulate the excitability of PFC neurons remains elusive. In this study, we recorded the native M-current from PFC layer V pyramidal neurons in rat brain slices and showed that it modulated the intrinsic excitability and synaptic responses of PFC pyramidal neurons. Application of a specific M-channel blocker XE991 (40 μmol/L) or opener retigabine (10 μmol/L) resulted in inhibition or activation of M-current, respectively. In the current-clamp recordings, inhibition of M-current was evidenced by the increased average spike frequency and the reduced first inter-spike interval (ISI), spike onset latency and fast afterhyperpolarization (fAHP), whereas activation of M-current caused opposite responses. Furthermore, inhibition of M-current significantly increased the amplitude of excitatory postsynaptic potentials (EPSPs) and depolarized the resting membrane potential (RMP) without affecting the miniature EPSC (mEPSC) frequency. These data demonstrate that voltage-gated neuronal Kv7/KCNQ/M-current modulates the excitability and synaptic transmission of PFC neurons, suggesting that pharmacological modulation of M-current in the PFC may exert beneficial effects on cognitive deficits implicated in the pathophysiology of neuropsychiatric disorders.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Casida, M.E.
1995-03-01
The now classic optimized-effective-potential (OEP) approach of Sharp and Horton [Phys Rev. 90, 317 (1953)] and Talman and Shadwick [Phys. Rev. A 14, 36 (1976)] seeks the local potential that is variationally optimized to best approximate the Hartree-Fock exchange operator. The resulting OEP can be identified as the exchange potential of Kohn-Sham density-functional theory. The present work generalizes this OEP approach to treat the correlated case, and shows that the Kohn-Sham exchange-correlation potential is the variationally best local approximation to the exchange-correlation self-energy. This provides a variational derivation of the equation for the exact exchange-correlation potential that was derived bymore » Sham and Schlueter using a density condition. Implications for an approximate physical interpretation of the Kohn-Sham orbitals are discussesd. A correlated generalization of the Sharp-Horton--Krieger-Li-Iafrate [Phys Lett. A 146, 256 (1990)] approximation of the exchange potential is introduced in the quasiparticle limit.« less
Test-retest reliability of functional connectivity networks during naturalistic fMRI paradigms.
Wang, Jiahui; Ren, Yudan; Hu, Xintao; Nguyen, Vinh Thai; Guo, Lei; Han, Junwei; Guo, Christine Cong
2017-04-01
Functional connectivity analysis has become a powerful tool for probing the human brain function and its breakdown in neuropsychiatry disorders. So far, most studies adopted resting-state paradigm to examine functional connectivity networks in the brain, thanks to its low demand and high tolerance that are essential for clinical studies. However, the test-retest reliability of resting-state connectivity measures is moderate, potentially due to its low behavioral constraint. On the other hand, naturalistic neuroimaging paradigms, an emerging approach for cognitive neuroscience with high ecological validity, could potentially improve the reliability of functional connectivity measures. To test this hypothesis, we characterized the test-retest reliability of functional connectivity measures during a natural viewing condition, and benchmarked it against resting-state connectivity measures acquired within the same functional magnetic resonance imaging (fMRI) session. We found that the reliability of connectivity and graph theoretical measures of brain networks is significantly improved during natural viewing conditions over resting-state conditions, with an average increase of almost 50% across various connectivity measures. Not only sensory networks for audio-visual processing become more reliable, higher order brain networks, such as default mode and attention networks, but also appear to show higher reliability during natural viewing. Our results support the use of natural viewing paradigms in estimating functional connectivity of brain networks, and have important implications for clinical application of fMRI. Hum Brain Mapp 38:2226-2241, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
Li, Lian-Ju; Zhu, Zhi-Wei; Zhao, Wei; Tao, Sha-Sha; Li, Bao-Zhu; Xu, Shu-Zhen; Wang, Jie-Bing; Zhang, Ming-Yue; Wu, Jun; Leng, Rui-Xue; Fan, Yin-Guang; Pan, Hai-Feng; Ye, Dong-Qing
2018-04-26
Circular RNAs (circRNAs) represent as a class of non-coding RNAs which form covalently closed RNA circles, and their extensive expression and conservation in mammals are observed. CircRNAs regulate gene expression through acting as competitive endogenous RNAs (ceRNAs) and modulating gene transcription. Accumulating evidence supports the implication of circRNAs in a variety of human diseases. Yet, study exploring the role of circRNAs in systemic lupus erythematosus (SLE) is lacking. The present study measured the circRNAs expression profiles in T cells from SLE patients and healthy controls with human circRNA microarray and identified 127 differentially expressed circRNAs in SLE patients. Downregulation of hsa_circ_0045272 in SLE T cells was verified with quantitative PCR. Jurkat cells with stable hsa_circ_0045272 knockdown were generated using specific lentiviral shRNA for functional studies. Flow cytometric analysis indicated that hsa_circ_0045272 knockdown significantly upregulated the early apoptosis of Jurkat cells. Meanwhile, enzyme-linked immunosorbent assay showed that hsa_circ_0045272 knockdown significantly enhanced IL-2 production of activated Jurkat cells. ceRNAs were then predicted for hsa_circ_0045272 and the significant downregulation of two mRNAs predicted as its ceRNAs, NM_003466 (PAX8) and NM_015177 (DTX4), but not their corresponding proteins was validated. Furthermore, dual luciferase reporter assay indicated binding of hsa_circ_0045272 with hsa-miR-6127. circRNAs-mRNAs coexpression networks showed the correlation of circRNAs with mRNAs and provided additional clues to circRNA functions. Our study demonstrated the dysregulated circRNAs in SLE and revealed function of hsa_circ_0045272 in negatively regulating apoptosis and IL-2 secretion and its potential mechanism. The implication of hsa_circ_0045272 and other abnormal circRNAs in SLE merits further investigation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Hormones and immune function: implications of aging.
Arlt, Wiebke; Hewison, Martin
2004-08-01
Aging is associated with a decline in immunity described as immunosenescence. This is paralleled by a decline in the production of several hormones, as typically illustrated by the menopausal loss of ovarian oestrogen production. However, other hormonal changes that occur with aging and that potentially impact on immune function include the release of the pineal gland hormone melatonin and pituitary growth hormone, adrenal production of dehydroepiandrosterone and tissue-specific availability of active vitamin D. It remains to be established whether hormonal changes with aging actually contribute to immunosenescence and this area is at the interface of fact and fiction, clearly inviting systematic research efforts. As a step in this direction, the present review summarizes established facts on the physiology of secretion and function of hormones that, in most cases, decline with aging and that are likely to affect the immune system.
Immunological function of vitamin D during human pregnancy.
Ji, Jin-Lu; Muyayalo, Kahinho P; Zhang, Yong-Hong; Hu, Xiao-Hui; Liao, Ai-Hua
2017-08-01
The well-established classic role of vitamin D is implicated in the regulation of the balance between calcium and phosphorus. Furthermore, vitamin D is also involved in many non-classic physiological processes, mainly including the regulation of cell proliferation, differentiation, apoptosis and immune function, participation in the inflammatory response and maintenance of genome stability function. During pregnancy, vitamin D receptor and its metabolic enzymes are expressed at the placenta and decidua, indicating the potential role in the mechanism of immunomodulation at the maternal-fetal interface. The insufficiency or deficiency of vitamin D may affect the mother directly and is related to specific pregnancy outcomes, such as preeclampsia, gestational diabetes, and recurrent miscarriage. This article reviews the effects of vitamin D on immune regulation during pregnancy. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Franck, Grégory; Mawson, Thomas; Sausen, Grasiele; Salinas, Manuel; Masson, Gustavo Santos; Cole, Andrew; Beltrami-Moreira, Marina; Chatzizisis, Yiannis; Quillard, Thibault; Tesmenitsky, Yevgenia; Shvartz, Eugenia; Sukhova, Galina K.; Swirski, Filip K.; Nahrendorf, Matthias; Aikawa, Elena; Croce, Kevin J.; Libby, Peter
2017-01-01
Rationale Superficial erosion currently causes up to a third of acute coronary syndromes (ACS), yet we lack understanding of its mechanisms. Thrombi due to superficial intimal erosion characteristically complicate matrix-rich atheromata in regions of flow perturbation. Objective This study tested in vivo the involvement of disturbed flow, and of neutrophils, hyaluronan, and TLR2 ligation in superficial intimal injury, a process implicated in superficial erosion. Methods and Results : In mouse carotid arteries with established intimal lesions tailored to resemble the substrate of human eroded plaques, acute flow perturbation promoted downstream endothelial cell (EC) activation, neutrophil accumulation, EC death and desquamation, and mural thrombosis. Neutrophil loss-of-function limited these findings. TLR2 agonism activated luminal ECs, and deficiency of this innate immune receptor decreased intimal neutrophil adherence in regions of local flow disturbance, reducing EC injury and local thrombosis (p<0.05). Conclusions These results implicate flow disturbance, neutrophils, and TLR2 signaling as mechanisms that contribute to superficial erosion, a cause of ACS of likely growing importance in the statin era. PMID:28428204
Measurement, methods, and divergent patterns: Reassessing the effects of same-sex parents.
Cheng, Simon; Powell, Brian
2015-07-01
Scholars have noted that survey analysis of small subsamples-for example, same-sex parent families-is sensitive to researchers' analytical decisions, and even small differences in coding can profoundly shape empirical patterns. As an illustration, we reassess the findings of a recent article by Regnerus regarding the implications of being raised by gay and lesbian parents. Taking a close look at the New Family Structures Study (NFSS), we demonstrate the potential for misclassifying a non-negligible number of respondents as having been raised by parents who had a same-sex romantic relationship. We assess the implications of these possible misclassifications, along with other methodological considerations, by reanalyzing the NFSS in seven steps. The reanalysis offers evidence that the empirical patterns showcased in the original Regnerus article are fragile-so fragile that they appear largely a function of these possible misclassifications and other methodological choices. Our replication and reanalysis of Regnerus's study offer a cautionary illustration of the importance of double checking and critically assessing the implications of measurement and other methodological decisions in our and others' research. Copyright © 2015 Elsevier Inc. All rights reserved.
Sgnaolin, V; Pereira, T C B; Bogo, M R; Zanin, R; Battastini, A M O; Morrone, F B; Campos, M M
2013-08-01
Kinins and their receptors have been recently implicated in cancer. Using functional and molecular approaches, we investigated the relevance of kinin B1 and B2 receptors in bladder cancer. Functional studies were conducted using bladder cancer cell lines, and human biopsies were employed for molecular studies. Both B1 des-Arg(9)-BK and B2 BK receptor agonists stimulated the proliferation of grade 3-derived T24 bladder cancer cells. Furthermore, treatment with B1 and B2 receptor antagonists (SSR240612 and HOE140) markedly inhibited the proliferation of T24 cells. Only higher concentrations of BK increased the proliferation of the grade 1 bladder cancer cell line RT4, while des-Arg(9)-BK completely failed to induce its proliferation. Real-time PCR revealed that the mRNA expression of kinin receptors, particularly B1 receptors, was increased in T24 cells relative to RT4 cells. Data from bladder cancer human biopsies revealed that B1 receptor expression was increased in all tumor samples and under conditions of chronic inflammation. We also show novel evidence demonstrating that the pharmacological inhibition of PI3Kγ (phosphatidylinositol 3-kinase) with AS252424, concentration-dependently reduced T24 cell proliferation induced by BK or des-Arg(9)-BK. Finally, the incubation of T24 cells with kinin agonists led to a marked activation of the PI3K/AKT and ERK 1/2 signaling pathways, whereas p38 MAP kinase remained unaffected. Kinin receptors, especially B1 receptors, appear to be implicated in bladder cancer progression. It is tempting to suggest that selective kinin antagonists might represent potential alternative therapies for bladder cancer.
Inappropriate trust in technology: implications for critical care nurses.
Browne, Mike; Cook, Penny
2011-01-01
To explore evidence from the literature that critical care nurses may have inappropriate levels of trust in the technological equipment they use and the implications of this for patient safety. Nurses in intensive care units are required to observe the operation of an array of complex equipment. Failure of this equipment can have potentially fatal consequences for the patient. Research from other settings, such as the work of airline pilots, suggests that experienced operators of highly reliable automation may display inappropriately high levels of trust in the automation and this can lead to inadequate monitoring of the equipment by the operator. Inadequate monitoring means that the operator may fail to notice that the equipment is not functioning correctly which may have serious consequences. An initial search was made of a number of databases including Academic Search Premier, CINAHL, Pubmed and ScienceDirect. Extensive use was also made of citations found in articles uncovered by this initial search. Evidence suggests that there is potential for critical care nurses to display complacent attitudes. In addition, there are a number of reasons why the consequences of this complacency are not as visible as in other settings. If nurses are not aware of the potential and consequences of inappropriate trust, there is a real possibility that patients may suffer harm because of it. There is an urgent need for more research to identify direct evidence of complacency and its consequences. There is also a need for these issues to be highlighted in the training of intensive care nurses and there are implications for intensive care unit practice protocols and equipment manufacturers. © 2011 The Authors. Nursing in Critical Care © 2011 British Association of Critical Care Nurses.
Glial and Neuroimmune Mechanisms as Critical Modulators of Drug Use and Abuse.
Lacagnina, Michael J; Rivera, Phillip D; Bilbo, Staci D
2017-01-01
Drugs of abuse cause persistent alterations in synaptic plasticity that may underlie addiction behaviors. Evidence suggests glial cells have an essential and underappreciated role in the development and maintenance of drug abuse by influencing neuronal and synaptic functions in multifaceted ways. Microglia and astrocytes perform critical functions in synapse formation and refinement in the developing brain, and there is growing evidence that disruptions in glial function may be implicated in numerous neurological disorders throughout the lifespan. Linking evidence of function in health and under pathological conditions, this review will outline the glial and neuroimmune mechanisms that may contribute to drug-abuse liability, exploring evidence from opioids, alcohol, and psychostimulants. Drugs of abuse can activate microglia and astrocytes through signaling at innate immune receptors, which in turn influence neuronal function not only through secretion of soluble factors (eg, cytokines and chemokines) but also potentially through direct remodeling of the synapses. In sum, this review will argue that neural-glial interactions represent an important avenue for advancing our understanding of substance abuse disorders.
Rare platelet GPCR variants: what can we learn?
Nisar, S P; Jones, M L; Cunningham, M R; Mumford, A D; Mundell, S J
2015-07-01
Platelet-expressed GPCRs are critical regulators of platelet function. Pharmacological blockade of these receptors forms a powerful therapeutic tool in the treatment and prevention of arterial thrombosis associated with coronary atherosclerosis and ischaemic stroke. However, anti-thrombotic drug therapy is associated with high inter-patient variability in therapeutic response and adverse bleeding side effects. In order to optimize the use of existing anti-platelet drugs and to develop new therapies, more detailed knowledge is required relating to the molecular mechanisms that regulate GPCR and therefore platelet function. One approach has been to identify rare, function-disrupting mutations within key platelet proteins in patients with bleeding disorders. In this review, we describe how an integrated functional genomics strategy has contributed important structure-function information about platelet GPCRs with specific emphasis upon purinergic and thromboxane A2 receptors. We also discuss the potential implications these findings have for pharmacotherapy and for understanding the molecular basis of mild bleeding disorders. © 2014 The British Pharmacological Society.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huynh, Mioy T.; Anson, Colin W.; Cavell, Andrew C.
Quinones participate in diverse electron transfer and proton-coupled electron transfer processes in chemistry and biology. An experimental study of common quinones reveals a non-linear correlation between the 1 e – and 2 e –/2 H + reduction potentials. This unexpected observation prompted a computational study of 128 different quinones, probing their 1 e – reduction potentials, pKa values, and 2 e –/2 H + reduction potentials. The density functional theory calculations reveal an approximately linear correlation between these three properties and an effective Hammett constant associated with the quinone substituent(s). However, deviations from this linear scaling relationship are evident formore » quinones that feature halogen substituents, charged substituents, intramolecular hydrogen bonding in the hydroquinone, and/or sterically bulky substituents. These results, particularly the different substituent effects on the 1 e – versus 2 e – /2 H + reduction potentials, have important implications for designing quinones with tailored redox properties.« less
Cheng, Wei; Rolls, Edmund T; Zhang, Jie; Sheng, Wenbo; Ma, Liang; Wan, Lin; Luo, Qiang; Feng, Jianfeng
2017-03-01
A powerful new method is described called Knowledge based functional connectivity Enrichment Analysis (KEA) for interpreting resting state functional connectivity, using circuits that are functionally identified using search terms with the Neurosynth database. The method derives its power by focusing on neural circuits, sets of brain regions that share a common biological function, instead of trying to interpret single functional connectivity links. This provides a novel way of investigating how task- or function-related networks have resting state functional connectivity differences in different psychiatric states, provides a new way to bridge the gap between task and resting-state functional networks, and potentially helps to identify brain networks that might be treated. The method was applied to interpreting functional connectivity differences in autism. Functional connectivity decreases at the network circuit level in 394 patients with autism compared with 473 controls were found in networks involving the orbitofrontal cortex, anterior cingulate cortex, middle temporal gyrus cortex, and the precuneus, in networks that are implicated in the sense of self, face processing, and theory of mind. The decreases were correlated with symptom severity. Copyright © 2017. Published by Elsevier Inc.
Potential of mean force of DNA guided assemblies past Debye-Hückel regime
NASA Astrophysics Data System (ADS)
Girard, Martin; Seo, Soyoung; Li, Yaohua; Mirkin, Chad; Olvera de La Cruz, Monica
Many of the bioinspired systems make use of biopolymers such as polypeptides or DNA. The latter is widely used in self-assembled systems, from colloidal crystals to origami construction. In these systems, salt is commonly required to screen the electrostatic repulsion between the strands. In the classical Debye-Hückel picture, salt ions are point particles and the screening distance is a decreasing monotonic function of salt concentration. This picture breaks down at moderate salt concentrations, where the behavior becomes non-monotonic. In this talk, we will show results for potential of mean force of DNA grafted colloids obtained through multiscale molecular dynamics. In this picture, the highly charged DNA causes non-trivial behavior at moderate salt concentrations (c 0 . 3 - 0 . 7 M), namely increase of repulsion for non-complementary DNA strands while repulsion decreases for complementary strands. We will show spatial cluster distribution as function of size and charge as well as implications for experimental systems.
Aging and Down syndrome: implications for physical therapy.
Barnhart, Robert C; Connolly, Barbara
2007-10-01
The number of people over the age of 60 years with lifelong developmental delays is predicted to double by 2030. Down syndrome (DS) is the most frequent chromosomal cause of developmental delays. As the life expectancy of people with DS increases, changes in body function and structure secondary to aging have the potential to lead to activity limitations and participation restrictions for this population. The purpose of this update is to: (1) provide an overview of the common body function and structure changes that occur in adults with DS as they age (thyroid dysfunction, cardiovascular disorders, obesity, musculoskeletal disorders, Alzheimer disease, depression) and (2) apply current research on exercise to the prevention of activity limitations and participation restrictions. As individuals with DS age, a shift in emphasis from disability prevention to the prevention of conditions that lead to activity and participation limitations must occur. Exercise programs appear to have potential to positively affect the overall health of adults with DS, thereby increasing the quality of life and years of healthy life for these individuals.
The human gut microbiota and virome: Potential therapeutic implications.
Scarpellini, Emidio; Ianiro, Gianluca; Attili, Fabia; Bassanelli, Chiara; De Santis, Adriano; Gasbarrini, Antonio
2015-12-01
Human gut microbiota is a complex ecosystem with several functions integrated in the host organism (metabolic, immune, nutrients absorption, etc.). Human microbiota is composed by bacteria, yeasts, fungi and, last but not least, viruses, whose composition has not been completely described. According to previous evidence on pathogenic viruses, the human gut harbours plant-derived viruses, giant viruses and, only recently, abundant bacteriophages. New metagenomic methods have allowed to reconstitute entire viral genomes from the genetic material spread in the human gut, opening new perspectives on the understanding of the gut virome composition, the importance of gut microbiome, and potential clinical applications. This review reports the latest evidence on human gut "virome" composition and its function, possible future therapeutic applications in human health in the context of the gut microbiota, and attempts to clarify the role of the gut "virome" in the larger microbial ecosystem. Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Delayed collapses of Bose-Einstein condensates in relation to anti-de Sitter gravity.
Biasi, Anxo F; Mas, Javier; Paredes, Angel
2017-03-01
We numerically investigate spherically symmetric collapses in the Gross-Pitaevskii equation with attractive nonlinearity in a harmonic potential. Even below threshold for direct collapse, the wave function bounces off from the origin and may eventually become singular after a number of oscillations in the trapping potential. This is reminiscent of the evolution of Einstein gravity sourced by a scalar field in anti de Sitter space where collapse corresponds to black-hole formation. We carefully examine the long time evolution of the wave function for continuous families of initial states in order to sharpen out this qualitative coincidence which may bring new insights in both directions. On the one hand, we comment on possible implications for the so-called Bosenova collapses in cold atom Bose-Einstein condensates. On the other hand, Gross-Pitaevskii provides a toy model to study the relevance of either the resonance conditions or the nonlinearity for the problem of anti de Sitter instability.
Ren, Dayong; Li, Chang; Qin, Yanqing; Yin, Ronglan; Du, Shouwen; Liu, Hongfeng; Zhang, Yanfang; Wang, Cuiyan; Rong, Fengjun; Jin, Ningyi
2015-10-01
Here we evaluate the immunomodulatory function of two potential probiotic strains, Lactobacillus salivarius CICC 23174 and Lactobacillus plantarum CGMCC 1.557. Mice were fed with each Lactobacillus strain at different doses for several consecutive days. The effects of the two probiotic strains on immune organs, immune cells and immune molecules were investigated on days 10 and 20. Both Lactobacillus strains increased the spleen index, improved the spleen lymphocyte transformation rate, enhanced sIgA production and improved the number of CD11c(+) CD80(+) double-positive cells. L. plantarum CGMCC 1.557 was the more active strain in enhancing the phagocytic activity of macrophages, while, L. salivarius CICC 23174 was the more effective strain at maintaining the Th1/Th2 balance. This study suggests that these two Lactobacillus strains have beneficial effects on regulation of immune responses, which has promising implications for the development of ecological agents and functional foods. Copyright © 2015 Elsevier Ltd. All rights reserved.
Hamdani, El Hassan; Gudbrandsen, Marius; Bjørkmo, Mona; Chaudhry, Farrukh Abbas
2012-11-01
Activation of NMDA receptor requires two co-agonists, glutamate and glycine. Despite its intrinsic role in brain functions molecular mechanisms involved in glutamate replenishment and identification of the origin of glycine have eluded characterization. We have performed direct measurements of glycine flux by SN2 (Slc38a5; also known as SNAT5), executed extensive electrophysiological characterization as well as implemented ratiometric analyses to show that SN2 transport resembles SN1 in mechanism but differ in functional implications. We report that rat SN2 mediates electroneutral and bidirectional transport of glutamine and glycine at perisynaptic astroglial membranes. Sophisticated coupled and uncoupled movements of H(+) differentially associate with glutamine and glycine transport by SN2 and regulate pH(i) and the release mode of the transporter. Consequently, SN2 doubles as a transmitter precursor furnisher and a potential regulator of NMDA receptors. Copyright © 2012 Wiley Periodicals, Inc.
On the deep structure of social affect: Attitudes, emotions, sentiments, and the case of "contempt".
Gervais, Matthew M; Fessler, Daniel M T
2017-01-01
Contempt is typically studied as a uniquely human moral emotion. However, this approach has yielded inconclusive results. We argue this is because the folk affect concept "contempt" has been inaccurately mapped onto basic affect systems. "Contempt" has features that are inconsistent with a basic emotion, especially its protracted duration and frequently cold phenomenology. Yet other features are inconsistent with a basic attitude. Nonetheless, the features of "contempt" functionally cohere. To account for this, we revive and reconfigure the sentiment construct using the notion of evolved functional specialization. We develop the Attitude-Scenario-Emotion (ASE) model of sentiments, in which enduring attitudes represent others' social-relational value and moderate discrete emotions across scenarios. Sentiments are functional networks of attitudes and emotions. Distinct sentiments, including love, respect, like, hate, and fear, track distinct relational affordances, and each is emotionally pluripotent, thereby serving both bookkeeping and commitment functions within relationships. The sentiment contempt is an absence of respect; from cues to others' low efficacy, it represents them as worthless and small, muting compassion, guilt, and shame and potentiating anger, disgust, and mirth. This sentiment is ancient yet implicated in the ratcheting evolution of human ultrasocialty. The manifolds of the contempt network, differentially engaged across individuals and populations, explain the features of "contempt," its translatability, and its variable experience as "hot" or "cold," occurrent or enduring, and anger-like or disgust-like. This rapprochement between psychological anthropology and evolutionary psychology contributes both methodological and empirical insights, with broad implications for understanding the functional and cultural organization of social affect.
Schubert, Klaus Oliver; Föcking, Melanie; Cotter, David R
2015-09-01
Neuropathological changes of the hippocampus have been associated with psychotic disorders such as schizophrenia and bipolar disorder. Recent work has particularly implicated hippocampal GABAergic interneurons in the pathophysiology of these diseases. However, the molecular mechanisms underlying structural and cellular hippocampal pathology remain poorly understood. We used data from comprehensive difference-in-gel electrophoresis (2-D DIGE) investigations of postmortem human hippocampus of people with schizophrenia and bipolar disorder, covering the acidic (isoelectric point (pI) between pH4 and 7) and, separately, the basic (pI between pH6 and 11) sub-proteome, for Ingenuity Pathway Analysis (IPA) of implicated protein networks and pathways. Comparing disease and control cases, we identified 58 unique differentially expressed proteins in schizophrenia, and 70 differentially expressed proteins in bipolar disorder, using mass spectrometry. IPA implicated, most prominently, 14-3-3 and aryl hydrocarbon receptor signaling in schizophrenia, and gluconeogenesis/glycolysis in bipolar disorder. Both disorders were characterized by alterations of proteins involved in the oxidative stress response, mitochondrial function, and protein-endocytosis, -trafficking, -degradation, and -ubiquitination. These findings are interpreted with a focus on GABAergic interneuron pathology in the hippocampus. Copyright © 2015 Elsevier B.V. All rights reserved.
Browaldh, Nanna; Bautista, Tara G; Dutschmann, Mathias; Berkowitz, Robert G
2016-11-01
To review the scientific literature on the relationship between Kölliker-Fuse nucleus (KF) and cranial nerve function in animal models, with view to evaluating the potential role of KF maturation in explaining age-related normal physiologic parameters and developmental and acquired impairment of cranial nerve function in humans. Medical databases (Medline and PubMed). Studies investigating evidence of KF activity responsible for a specific cranial nerve function that were based on manipulation of KF activity or the use of neural markers were included. Twenty studies were identified that involved the trigeminal (6 studies), vagus (9), and hypoglossal nerves (5). These pertained specifically to a role of the KF in mediating the dive reflex, laryngeal adductor control, swallowing function and upper airway tone. The KF acts as a mediator of a number of important functions that relate primarily to laryngeal closure, upper airway tone and swallowing. These areas are characterized by a variety of disorders that may present to the otolaryngologist, and hence the importance of understanding the role played by the KF in maintaining normal function.
The impact of tinnitus upon cognition in adults: A systematic review.
Tegg-Quinn, Susan; Bennett, Rebecca J; Eikelboom, Robert H; Baguley, David M
2016-10-01
To systematically review and analyse experimental outcomes of studies exploring the impact of tinnitus upon cognitive function and their implications for clinical management of invasive tinnitus. A systematic and descriptive review. Eighteen studies were identified investigating the impact of tinnitus on cognitive function. The 18 studies evaluated cognitive function using 24 different objective behavioural tests, nine electrophysiological recordings, one oculomotor test, and one self-report questionnaire. The studies spanned 18 years and revealed numerous interactions potentially contributing to the cognitive difficulties frequently reported by people with invasive tinnitus. The studies indicate a clear association between tinnitus and aspects of cognitive function, specifically the executive control of attention. Tinnitus impairs cognitive function by way of impact upon executive control of attention. Clinical management of patients reporting tinnitus and cognitive difficulties requires an understanding of the reciprocal relationship between tinnitus and cognitive function, with additive effects of anxiety, depression, and somatic cognitive bias. Further study is required to establish the impact of advancing age, hearing loss, anxiety, depression tinnitus duration, and distress upon cognitive function in people with invasive tinnitus.
VASCULAR ACTIONS OF ESTROGENS: FUNCTIONAL IMPLICATIONS
Miller, Virginia M.; Duckles, Sue P.
2009-01-01
The impact of estrogen exposure in preventing or treating cardiovascular disease is controversial. But it is clear that estrogen has important effects on vascular physiology and pathophysiology, with potential therapeutic implications. Therefore, it is the goal of this review to summarize, using an integrated approach, current knowledge of the vascular effects of estrogen, both in humans and in experimental animals. Aspects of estrogen synthesis and receptors, as well as general mechanisms of estrogenic action are reviewed with an emphasis on issues particularly relevant to the vascular system. Recent understanding of the impact of estrogen on mitochondrial function suggests that the longer lifespan of women compared to men may depend in part on the ability of estrogen to decrease production of reactive oxygen species in mitochondria. Mechanisms by which estrogen increases endothelial vasodilator function, promotes angiogenesis and modulates autonomic function are summarized. Key aspects of the relevant pathophysiology of inflammation, atherosclerosis, stroke, migraine and thrombosis are reviewed concerning current knowledge of estrogenic effects. A number of emerging concepts are addressed throughout. These include the importance of estrogenic formulation and route of administration and the impact of genetic polymorphisms, either in estrogen receptors or in enzymes responsible for estrogen metabolism, on responsiveness to hormone treatment. The importance of local metabolism of estrogenic precursors and the impact of timing for initiation of treatment and its duration are also considered. While consensus opinions are emphasized, controversial views are presented in order to stimulate future research. PMID:18579753
Sugiura, Lisa; Hata, Masahiro; Matsuba-Kurita, Hiroko; Uga, Minako; Tsuzuki, Daisuke; Dan, Ippeita; Hagiwara, Hiroko; Homae, Fumitaka
2018-01-01
Learning a second language (L2) proceeds with individual approaches to proficiency in the language. Individual differences including sex, as well as working memory (WM) function appear to have strong effects on behavioral performance and cortical responses in L2 processing. Thus, by considering sex and WM capacity, we examined neural responses during L2 sentence processing as a function of L2 proficiency in young adolescents. In behavioral tests, girls significantly outperformed boys in L2 tests assessing proficiency and grammatical knowledge, and in a reading span test (RST) assessing WM capacity. Girls, but not boys, showed significant correlations between L2 tests and RST scores. Using functional near-infrared spectroscopy (fNIRS) and event-related potential (ERP) simultaneously, we measured cortical responses while participants listened to syntactically correct and incorrect sentences. ERP data revealed a grammaticality effect only in boys in the early time window (100–300 ms), implicated in phrase structure processing. In fNIRS data, while boys had significantly increased activation in the left prefrontal region implicated in syntactic processing, girls had increased activation in the posterior language-related region involved in phonology, semantics, and sentence processing with proficiency. Presumably, boys implicitly focused on rule-based syntactic processing, whereas girls made full use of linguistic knowledge and WM function. The present results provide important fundamental data for learning and teaching in L2 education. PMID:29568265
Baladi, J F; Bailey, P A; Black, S; Bouchard, R W; Farcnik, K D; Gauthier, S; Kertesz, A; Mohr, E; Robillard, A
2000-12-01
Clinical studies have shown that patients with Alzheimer's disease (AD) who are treated with rivastigmine have statistically significantly better scores on 5 scales used to assess AD than control patients receiving placebo. However, the clinical meaning and cost implications of these differences are not clear. The purpose of this study was to assess the clinical meaning and cost implications of statistically significant results obtained in clinical trials of rivastigmine for the treatment of AD. Potential cost implications for the health care system, caregivers, and society are considered. Data on clinical effects of rivastigmine were obtained from published North American and European clinical studies of patients with mild to moderately severe AD receiving rivastigmine 6 to 12 mg/d (n = 828) or placebo (n = 647). Differences in scores on the Alzheimer's Disease Assessment Scale-Cognitive Function, Clinician's Interview-Based Impression of Change with both clinical and caregiver information considered, Progressive Deterioration Scale, Mini-Mental State Examination (MMSE), and Global Deterioration Scale were assessed. A convenience panel of 9 Canadian specialists experienced in the treatment of AD provided their opinions on the clinical importance of the trial results. Chart review was performed to identify specific behaviors that improved, and cost implications of improvements were assessed. The panel determined that statistically significant differences in scores on all scales except the MMSE were likely associated with functional or cognitive differences that were clinically relevant for patients, reflecting stabilization that would have beneficial consequences for caregivers and health care resource use. Subsequent chart review showed that improvement on specific scale items confirmed the physician panel's opinion. Analysis of possible cost implications to society indicated that medication expenditures would be offset largely by delays in the need for paid home care and institutionalization, positive effects on caregiver health, and less time lost from work for the caregiver. From the perspective of a Canadian specialist panel, rivastigmine treatment for AD produces clinically relevant effects for patients that are beneficial to caregivers. These effects suggest decreased use of caregiver resources and delays in the need for institutionalization, both of which reduce societal costs.
Creed, Irena F; Bergström, Ann-Kristin; Trick, Charles G; Grimm, Nancy B; Hessen, Dag O; Karlsson, Jan; Kidd, Karen A; Kritzberg, Emma; McKnight, Diane M; Freeman, Erika C; Senar, Oscar E; Andersson, Agneta; Ask, Jenny; Berggren, Martin; Cherif, Mehdi; Giesler, Reiner; Hotchkiss, Erin R; Kortelainen, Pirkko; Palta, Monica M; Vrede, Tobias; Weyhenmeyer, Gesa A
2018-03-15
Northern ecosystems are experiencing some of the most dramatic impacts of global change on Earth. Rising temperatures, hydrological intensification, changes in atmospheric acid deposition and associated acidification recovery, and changes in vegetative cover are resulting in fundamental changes in terrestrial-aquatic biogeochemical linkages. The effects of global change are readily observed in alterations in the supply of dissolved organic matter (DOM)-the messenger between terrestrial and lake ecosystems-with potentially profound effects on the structure and function of lakes. Northern terrestrial ecosystems contain substantial stores of organic matter and filter or funnel DOM, affecting the timing and magnitude of DOM delivery to surface waters. This terrestrial DOM is processed in streams, rivers, and lakes, ultimately shifting its composition, stoichiometry, and bioavailability. Here, we explore the potential consequences of these global change-driven effects for lake food webs at northern latitudes. Notably, we provide evidence that increased allochthonous DOM supply to lakes is overwhelming increased autochthonous DOM supply that potentially results from earlier ice-out and a longer growing season. Furthermore, we assess the potential implications of this shift for the nutritional quality of autotrophs in terms of their stoichiometry, fatty acid composition, toxin production, and methylmercury concentration, and therefore, contaminant transfer through the food web. We conclude that global change in northern regions leads not only to reduced primary productivity but also to nutritionally poorer lake food webs, with discernible consequences for the trophic web to fish and humans. © 2018 John Wiley & Sons Ltd.
Function as a Determinant of Speech Production--Implications for Language Development in Schools.
ERIC Educational Resources Information Center
Skull, John
The function of speech and its implications for studying, understanding, and promoting language development are explored in this paper. Function is considered to be the purpose of the speaker when speaking, variously termed context of situation, situation, context, circumstance, or mode. It is noted that very few studies of speech and speech…
Krzyzanowska, Agnieszka; Carro, Eva
2012-01-01
Morphological alterations of choroid plexus in Alzheimer’s disease (AD) have been extensively investigated. These changes include epithelial atrophy, thickening of the basement membrane, and stroma fibrosis. As a result, synthesis, secretory, and transportation functions are significantly altered resulting in decreased cerebrospinal fluid (CSF) turnover. Recent studies discuss the potential impacts of these changes, including the possibility of reduced resistance to stress insults and slow clearance of toxic compounds from CSF with specific reference to the amyloid peptide. Here, we review new evidences for AD-related changes in the choroid plexus. The data suggest that the significantly altered functions of the choroid plexus contribute to the multiparametric pathogenesis of late-onset AD. PMID:22563316
Neurobehavioral Disorder Associated With Prenatal Alcohol Exposure
Hagan, Joseph F.; Balachova, Tatiana; Bertrand, Jacquelyn; Chasnoff, Ira; Dang, Elizabeth; Fernandez-Baca, Daniel; Kable, Julie; Kosofsky, Barry; Senturias, Yasmin N.; Singh, Natasha; Sloane, Mark; Weitzman, Carol; Zubler, Jennifer
2017-01-01
Children and adolescents affected by prenatal exposure to alcohol who have brain damage that is manifested in functional impairments of neurocognition, self-regulation, and adaptive functioning may most appropriately be diagnosed with neurobehavioral disorder associated with prenatal exposure. This Special Article outlines clinical implications and guidelines for pediatric medical home clinicians to identify, diagnose, and refer children regarding neurobehavioral disorder associated with prenatal exposure. Emphasis is given to reported or observable behaviors that can be identified as part of care in pediatric medical homes, differential diagnosis, and potential comorbidities. In addition, brief guidance is provided on the management of affected children in the pediatric medical home. Finally, suggestions are given for obtaining prenatal history of in utero exposure to alcohol for the pediatric patient. PMID:27677572
Harnessing dendritic cells in inflammatory skin diseases.
Chu, Chung-Ching; Di Meglio, Paola; Nestle, Frank O
2011-02-01
The skin immune system harbors a complex network of dendritic cells (DCs). Recent studies highlight a diverse functional specialization of skin DC subsets. In addition to generating cellular and humoral immunity against pathogens, skin DCs are involved in tolerogenic mechanisms to ensure the maintenance of immune homeostasis, as well as in pathogenesis of chronic inflammation in the skin when excessive immune responses are initiated and unrestrained. Harnessing DCs by directly targeting DC-derived molecules or selectively modulate DC subsets is a convincing strategy to tackle inflammatory skin diseases. In this review we discuss recent advances underlining the functional specialization of skin DCs and discuss the potential implication for future DC-based therapeutic strategies. Copyright © 2011 Elsevier Ltd. All rights reserved.
Origins and implications of pluripotent stem cell variability and heterogeneity
Cahan, Patrick; Daley, George Q.
2014-01-01
Pluripotent stem cells constitute a platform to model disease and developmental processes and can potentially be used in regenerative medicine. However, not all pluripotent cell lines are equal in their capacity to differentiate into desired cell types in vitro. Genetic and epigenetic variations contribute to functional variability between cell lines and heterogeneity within clones. These genetic and epigenetic variations could ‘lock’ the pluripotency network resulting in residual pluripotent cells or alter the signalling response of developmental pathways leading to lineage bias. The molecular contributors to functional variability and heterogeneity in both embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are only beginning to emerge, yet they are crucial to the future of the stem cell field. PMID:23673969
PROBING HUMAN AND MONKEY ANTERIOR CINGULATE CORTEX IN VARIABLE ENVIRONMENTS
Walton, Mark E.; Mars, Rogier B.
2008-01-01
Previous research has identified the anterior cingulate cortex (ACC) as an important node in the neural network underlying decision making in primates. Decision making can, however, be studied under large variety of circumstances, ranging from the standard well-controlled lab situation to more natural, stochastic settings during which multiple agents interact. Here, we illustrate how these different varieties of decision making studied can influence theories of ACC function in monkeys. Converging evidence from unit recordings and lesions studies now suggest that the ACC is important for interpreting outcome information according to the current task context to guide future action selection. We then apply this framework to the study of human ACC function and discuss its potential implications. PMID:18189014
Manifestations and mechanisms of stem cell aging
Liu, Ling
2011-01-01
Adult stem cells exist in most mammalian organs and tissues and are indispensable for normal tissue homeostasis and repair. In most tissues, there is an age-related decline in stem cell functionality but not a depletion of stem cells. Such functional changes reflect deleterious effects of age on the genome, epigenome, and proteome, some of which arise cell autonomously and others of which are imposed by an age-related change in the local milieu or systemic environment. Notably, some of the changes, particularly epigenomic and proteomic, are potentially reversible, and both environmental and genetic interventions can result in the rejuvenation of aged stem cells. Such findings have profound implications for the stem cell–based therapy of age-related diseases. PMID:21502357
Ma, Di; Feng, Liangshu; Deng, Fang; Feng, Jia-Chun
2017-01-01
Research on attenuating the structural and functional deficits observed following ischemia-reperfusion has become increasingly focused on the therapeutic potential of ischemic postconditioning. In recent years, various methods and animal models of ischemic postconditioning have been utilized. The results of these numerous studies have indicated that the mechanisms underlying the neuroprotective effects of ischemic postconditioning may involve reductions in the generation of free radicals and inhibition of calcium overload, as well as the release of endogenous active substances, alterations in membrane channel function, and activation of protein kinases. Here we review the novel discovery, mechanism, key factors, and clinical application of ischemic postconditioning and discuss its implications for future research and problem of clinical practice.
Potential Applications of Polyamines in Agriculture and Plant Biotechnology.
Tiburcio, Antonio F; Alcázar, Rubén
2018-01-01
The polyamines putrescine, spermidine and spermine have been implicated in a myriad of biological functions in many organisms. Research done during the last decades has accumulated a large body of evidence demonstrating that polyamines are key modulators of plant growth and development. Different experimental approaches have been employed including the measurement of endogenous polyamine levels and the activities of polyamine metabolic enzymes, the study of the effects resulting from exogenous polyamine applications and chemical or genetic manipulation of endogenous polyamine titers. This chapter reviews the role of PAs in seed germination, root development, plant architecture, in vitro plant regeneration, flowering and plant senescence. Evidence presented here indicates that polyamines should be regarded as plant growth regulators with potential applications in agriculture and plant biotechnology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wicks, June; Jackson, Jennifer M.; Sturhahn, Wolfgang
We explore the effect of Mg/Fe substitution on the sound velocities of iron-rich (Mg 1 - xFe x)O, where x = 0.84, 0.94, and 1.0. Sound velocities were determined using nuclear resonance inelastic X-ray scattering as a function of pressure, approaching those of the lowermost mantle. The systematics of cation substitution in the Fe-rich limit has the potential to play an important role in the interpretation of seismic observations of the core-mantle boundary. By determining a relationship between sound velocity, density, and composition of (Mg,Fe)O, this study explores the potential constraints on ultralow-velocity zones at the core-mantle boundary.
Cellular and molecular basis of RV hypertrophy in congenital heart disease
Iacobazzi, D; Suleiman, M-S; Ghorbel, M; George, SJ; Caputo, M; Tulloh, RM
2016-01-01
RV hypertrophy (RVH) is one of the triggers of RV failure in congenital heart disease (CHD). Therefore, improving our understanding of the cellular and molecular basis of this pathology will help in developing strategic therapeutic interventions to enhance patient benefit in the future. This review describes the potential mechanisms that underlie the transition from RVH to RV failure. In particular, it addresses structural and functional remodelling that encompass contractile dysfunction, metabolic changes, shifts in gene expression and extracellular matrix remodelling. Both ischaemic stress and reactive oxygen species production are implicated in triggering these changes and will be discussed. Finally, RV remodelling in response to various CHDs as well as the potential role of biomarkers will be addressed. PMID:26516182
Vitamin D: Implications for Ocular Disease and Therapeutic Potential
Reins, Rose Y.; McDermott, Alison M.
2015-01-01
Vitamin D is a multifunctional hormone that is now known to play a significant role in a variety of biological functions in addition to its traditional role in regulating calcium homeostasis. There are a large number of studies demonstrating that adequate vitamin D levels are important in maintaining health and show that vitamin D is able to be utilized at local tissue sites. In the eye, we have increasing evidence of the association between disease and vitamin D. In this narrative review, we summarize recent findings on vitamin D and its relationship to various ocular pathologies and the therapeutic potential for some of these, as well as examine the basic science studies that demonstrate that vitamin D is biologically relevant in the eye. PMID:25724179
Ellard, Kristen K; Zimmerman, Jared P; Kaur, Navneet; Van Dijk, Koene R A; Roffman, Joshua L; Nierenberg, Andrew A; Dougherty, Darin D; Deckersbach, Thilo; Camprodon, Joan A
2018-05-01
Patients with bipolar depression are characterized by dysregulation across the full spectrum of mood, differentiating them from patients with unipolar depression. The ability to switch neural resources among the default mode network, salience network, and executive control network (ECN) has been proposed as a key mechanism for adaptive mood regulation. The anterior insula is implicated in the modulation of functional network switching. Differential connectivity between anterior insula and functional networks may provide insights into pathophysiological differences between bipolar and unipolar mood disorders, with implications for diagnosis and treatment. Resting-state functional magnetic resonance imaging data were collected from 98 subjects (35 unipolar, 24 bipolar, and 39 healthy control subjects). Pearson correlations were computed between bilateral insula seed regions and a priori defined target regions from the default mode network, salience network, and ECN. After r-to-z transformation, a one-way multivariate analysis of covariance was conducted to identify significant differences in connectivity between groups. Post hoc pairwise comparisons were conducted and Bonferroni corrections were applied. Receiver-operating characteristics were computed to assess diagnostic sensitivity. Patients with bipolar depression evidenced significantly altered right anterior insula functional connectivity with the inferior parietal lobule of the ECN relative to patients with unipolar depression and control subjects. Right anterior insula-inferior parietal lobule connectivity significantly discriminated patients with bipolar depression. Impaired functional connectivity between the anterior insula and the inferior parietal lobule of the ECN distinguishes patients with bipolar depression from those with unipolar depression and healthy control subjects. This finding highlights a pathophysiological mechanism with potential as a therapeutic target and a clinical biomarker for bipolar disorder, exhibiting reasonable sensitivity and specificity. Copyright © 2018 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
James M. Vose; Chelcy F. Miniat; Ge Sun; Peter V. Caldwell
2014-01-01
The potential expansion of freeze-tolerant (FT) Eucalyptus plantations in the United States has raised concerns about the implications for water resources. Modeling was used to examine the potential effects of expanding the distribution of FT Eucalyptus plantations in US Department of Agriculture Plant Hardiness Zones 8b and...
[Psychosocial interventions in dementia].
Kurz, A
2013-01-01
Psychosocial interventions improve cognitive abilities (cognitive stimulation, cognitive training), enhance emotional well-being (activity planning, reminiscence), reduce behavioral symptoms (aromatherapy, music therapy) and promote everyday functioning (occupational therapy). Through these effects they reinforce and augment pharmacological treatments for dementia. In addition, psychosocial interventions complement the treatment of patients by supporting family caregivers (educational groups, support programs). The potential of psychosocial interventions in dementia needs to be explored further in studies using improved methodology to determine effective components, clinical relevance and duration of effects, predictors of individual treatment response and health-economic implications.
Isolation and Phenotyping of Intestinal Macrophages.
Petit, Vanessa
2018-01-01
Macrophages are one of the most abundant leucocytes in the intestinal mucosa where they are essential for maintaining homeostasis. However they are also implicated in the pathogenesis of disorders such as inflammatory bowel disease (IBD), offering potential targets for novel therapies.Tissue macrophages are a heterogeneous population of immune cells that fulfill tissue-specific and niche-specific functions. These unique phenotypes likely reflect the heterogeneity of tissue macrophage origins and influence the tissue environment in which they reside. Here we describe how we can characterize and isolate the colonic macrophages.
The Roles of CD147 and/or Cyclophilin A in Kidney Diseases
Wang, Chunting; Zhang, Jicheng; Qie, Guoqiang
2014-01-01
CD147 is a widely expressed integral plasma membrane glycoprotein and has been involved in a variety of physiological and pathological activities in combination with different partners, including cyclophilins, caveolin-1, monocarboxylate transporters, and integrins. Recent data demonstrate that both CyPA and CD147 significantly contribute to renal inflammation, acute kidney injury, renal fibrosis, and renal cell carcinoma. Here we review the current understanding of cyclophilin A and CD147 expression and functions in kidney diseases and potential implications for treatment of kidney diseases. PMID:25580061
Bana, Laura; Minniti, Stefania; Salvati, Elisa; Sesana, Silvia; Zambelli, Vanessa; Cagnotto, Alfredo; Orlando, Antonina; Cazzaniga, Emanuela; Zwart, Rob; Scheper, Wiep; Masserini, Massimo; Re, Francesca
2014-10-01
Targeting amyloid-β peptide (Aβ) within the brain is a strategy actively sought for therapy of Alzheimer's disease (AD). We investigated the ability of liposomes bi-functionalized with phosphatidic acid and with a modified ApoE-derived peptide (mApoE-PA-LIP) to affect Aβ aggregation/disaggregation features and to cross in vitro and in vivo the blood-brain barrier (BBB). Surface plasmon resonance showed that bi-functionalized liposomes strongly bind Aβ (kD=0.6 μM), while Thioflavin-T and SDS-PAGE/WB assays show that liposomes inhibit peptide aggregation (70% inhibition after 72 h) and trigger the disaggregation of preformed aggregates (60% decrease after 120 h incubation). Moreover, experiments with dually radiolabelled LIP suggest that bi-functionalization enhances the passage of radioactivity across the BBB either in vitro (permeability=2.5×10(-5) cm/min, 5-fold higher with respect to mono-functionalized liposomes) or in vivo in healthy mice. Taken together, our results suggest that mApoE-PA-LIP are valuable nanodevices with a potential applicability in vivo for the treatment of AD. From the clinical editor: Bi-functionalized liposomes with phosphatidic acid and a modified ApoE-derived peptide were demonstrated to influence Aβ aggregation/disaggregation as a potential treatment in an Alzheimer's model. The liposomes were able to cross the blood-brain barrier in vitro and in vivo. Similar liposomes may become clinically valuable nanodevices with a potential applicability for the treatment of Alzheimer's disease. Copyright © 2014 Elsevier Inc. All rights reserved.
Functional Alignment of Metabolic Networks.
Mazza, Arnon; Wagner, Allon; Ruppin, Eytan; Sharan, Roded
2016-05-01
Network alignment has become a standard tool in comparative biology, allowing the inference of protein function, interaction, and orthology. However, current alignment techniques are based on topological properties of networks and do not take into account their functional implications. Here we propose, for the first time, an algorithm to align two metabolic networks by taking advantage of their coupled metabolic models. These models allow us to assess the functional implications of genes or reactions, captured by the metabolic fluxes that are altered following their deletion from the network. Such implications may spread far beyond the region of the network where the gene or reaction lies. We apply our algorithm to align metabolic networks from various organisms, ranging from bacteria to humans, showing that our alignment can reveal functional orthology relations that are missed by conventional topological alignments.
Oxidative Stress in Hypertension: Role of the Kidney
Araujo, Magali
2014-01-01
Abstract Significance: Renal oxidative stress can be a cause, a consequence, or more often a potentiating factor for hypertension. Increased reactive oxygen species (ROS) in the kidney have been reported in multiple models of hypertension and related to renal vasoconstriction and alterations of renal function. Nicotinamide adenine dinucleotide phosphate oxidase is the central source of ROS in the hypertensive kidney, but a defective antioxidant system also can contribute. Recent Advances: Superoxide has been identified as the principal ROS implicated for vascular and tubular dysfunction, but hydrogen peroxide (H2O2) has been implicated in diminishing preglomerular vascular reactivity, and promoting medullary blood flow and pressure natriuresis in hypertensive animals. Critical Issues and Future Directions: Increased renal ROS have been implicated in renal vasoconstriction, renin release, activation of renal afferent nerves, augmented contraction, and myogenic responses of afferent arterioles, enhanced tubuloglomerular feedback, dysfunction of glomerular cells, and proteinuria. Inhibition of ROS with antioxidants, superoxide dismutase mimetics, or blockers of the renin-angiotensin-aldosterone system or genetic deletion of one of the components of the signaling cascade often attenuates or delays the onset of hypertension and preserves the renal structure and function. Novel approaches are required to dampen the renal oxidative stress pathways to reduced O2−• rather than H2O2 selectivity and/or to enhance the endogenous antioxidant pathways to susceptible subjects to prevent the development and renal-damaging effects of hypertension. Antioxid. Redox Signal. 20, 74–101. PMID:23472618
A computational study of astrocytic glutamate influence on post-synaptic neuronal excitability.
Flanagan, Bronac; McDaid, Liam; Wade, John; Wong-Lin, KongFatt; Harkin, Jim
2018-04-01
The ability of astrocytes to rapidly clear synaptic glutamate and purposefully release the excitatory transmitter is critical in the functioning of synapses and neuronal circuits. Dysfunctions of these homeostatic functions have been implicated in the pathology of brain disorders such as mesial temporal lobe epilepsy. However, the reasons for these dysfunctions are not clear from experimental data and computational models have been developed to provide further understanding of the implications of glutamate clearance from the extracellular space, as a result of EAAT2 downregulation: although they only partially account for the glutamate clearance process. In this work, we develop an explicit model of the astrocytic glutamate transporters, providing a more complete description of the glutamate chemical potential across the astrocytic membrane and its contribution to glutamate transporter driving force based on thermodynamic principles and experimental data. Analysis of our model demonstrates that increased astrocytic glutamate content due to glutamine synthetase downregulation also results in increased postsynaptic quantal size due to gliotransmission. Moreover, the proposed model demonstrates that increased astrocytic glutamate could prolong the time course of glutamate in the synaptic cleft and enhances astrocyte-induced slow inward currents, causing a disruption to the clarity of synaptic signalling and the occurrence of intervals of higher frequency postsynaptic firing. Overall, our work distilled the necessity of a low astrocytic glutamate concentration for reliable synaptic transmission of information and the possible implications of enhanced glutamate levels as in epilepsy.
Underappreciated species in ecology: "ugly fish" in the northwest Atlantic Ocean.
Link, Jason S
2007-10-01
Species shifts and replacements are common in ecological studies. Observations thereof serve as the impetus for many ecological endeavors. Many of the species now known to dominate ecosystem functioning were largely ignored until studies of those underappreciated species elucidated their critical roles. Recognizing the potential importance of underappreciated species has implications for functional redundancies in ecosystems and should alter our approach to long-term monitoring. One example of an applied ecological system containing species shifts, underappreciated species, and potential changes in functional redundancies is the topic of fisheries. The demersal component of many fish communities usually consists of high-profile and commercially valuable species that are targets of fisheries, plus a diverse group of lesser known species that have minimal commercial value and focus. Yet ecologically these traditionally nontargeted species are often a major biomass sink in marine ecosystems and can also be critical in the functioning of bentho-demersal food webs. I examined the biomass trajectories of several species of skates, cottids, lophiids, anarhichadids, zooarcids, and similar species in the northeast U.S. Atlantic ecosystem to determine whether their relative abundance has changed across the past four decades. Distribution and stomach contents of these species were also evaluated over time to further elucidate the relative importance of these species. Landings of these underappreciated bentho-demersal fish were also examined in comparison to those species that historically have been commercially targeted. Of particular emphasis was the evaluation of evidence for sequential stock depletion and the ramifications for functional redundancy for this ecosystem. Results indicate that some of these fish species are now the dominant piscivores, benthivores, and scavengers in this ecosystem. These formerly under-studied species generally have either maintained a consistent population size or have increased in abundance (and expanded in distribution) over the past several decades. Nontraditionally targeted fish species are an often overlooked but important component of bentho-demersal fish communities. Implications for the energy flow and resilience specifically for future fisheries and generally for harvesting biological resources are significant, remaining critical issues for the world's ecosystems.
Synchrony and motor mimicking in chimpanzee observational learning
Fuhrmann, Delia; Ravignani, Andrea; Marshall-Pescini, Sarah; Whiten, Andrew
2014-01-01
Cumulative tool-based culture underwrote our species' evolutionary success, and tool-based nut-cracking is one of the strongest candidates for cultural transmission in our closest relatives, chimpanzees. However the social learning processes that may explain both the similarities and differences between the species remain unclear. A previous study of nut-cracking by initially naïve chimpanzees suggested that a learning chimpanzee holding no hammer nevertheless replicated hammering actions it witnessed. This observation has potentially important implications for the nature of the social learning processes and underlying motor coding involved. In the present study, model and observer actions were quantified frame-by-frame and analysed with stringent statistical methods, demonstrating synchrony between the observer's and model's movements, cross-correlation of these movements above chance level and a unidirectional transmission process from model to observer. These results provide the first quantitative evidence for motor mimicking underlain by motor coding in apes, with implications for mirror neuron function. PMID:24923651
Sun, Guihong; Roediger, Julia; Shi, Yun-Bo
2016-12-01
Organ-specific adult stem cells are essential for organ homeostasis, tissue repair and regeneration. The formation of such stem cells often takes place during postembryonic development, a period around birth in mammals when plasma thyroid hormone concentration is high. The life-long self-renewal of the intestinal epithelium has made mammalian intestine a valuable model to study the function and regulation and adult stem cells. On the other hand, much less is known about how the adult intestinal stem cells are formed during vertebrate development. Here, we will review some recent progresses on this subject, focusing mainly on the formation of the adult intestine during Xenopus metamorphosis. We will discuss the role of thyroid hormone signaling pathway in the process and potential molecular conservations between amphibians and mammals as well as the implications in organ homeostasis and human diseases.
The Aging Cardiovascular System: Understanding It at the Cellular and Clinical Levels.
Paneni, Francesco; Diaz Cañestro, Candela; Libby, Peter; Lüscher, Thomas F; Camici, Giovanni G
2017-04-18
Cardiovascular disease (CVD) presents a great burden for elderly patients, their caregivers, and health systems. Structural and functional alterations of vessels accumulate throughout life, culminating in increased risk of developing CVD. The growing elderly population worldwide highlights the need to understand how aging promotes CVD in order to develop new strategies to confront this challenge. This review provides examples of some major unresolved clinical problems encountered in daily cardiovascular practice as we care for elderly patients. Next, the authors summarize the current understanding of the mechanisms implicated in cardiovascular aging, and the potential for targeting novel pathways implicated in endothelial dysfunction, mitochondrial oxidative stress, chromatin remodeling, and genomic instability. Lastly, the authors consider critical aspects of vascular repair, including autologous transplantation of bone marrow-derived stem cells in elderly patients. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.
Synaptic, transcriptional and chromatin genes disrupted in autism.
De Rubeis, Silvia; He, Xin; Goldberg, Arthur P; Poultney, Christopher S; Samocha, Kaitlin; Cicek, A Erucment; Kou, Yan; Liu, Li; Fromer, Menachem; Walker, Susan; Singh, Tarinder; Klei, Lambertus; Kosmicki, Jack; Shih-Chen, Fu; Aleksic, Branko; Biscaldi, Monica; Bolton, Patrick F; Brownfeld, Jessica M; Cai, Jinlu; Campbell, Nicholas G; Carracedo, Angel; Chahrour, Maria H; Chiocchetti, Andreas G; Coon, Hilary; Crawford, Emily L; Curran, Sarah R; Dawson, Geraldine; Duketis, Eftichia; Fernandez, Bridget A; Gallagher, Louise; Geller, Evan; Guter, Stephen J; Hill, R Sean; Ionita-Laza, Juliana; Jimenz Gonzalez, Patricia; Kilpinen, Helena; Klauck, Sabine M; Kolevzon, Alexander; Lee, Irene; Lei, Irene; Lei, Jing; Lehtimäki, Terho; Lin, Chiao-Feng; Ma'ayan, Avi; Marshall, Christian R; McInnes, Alison L; Neale, Benjamin; Owen, Michael J; Ozaki, Noriio; Parellada, Mara; Parr, Jeremy R; Purcell, Shaun; Puura, Kaija; Rajagopalan, Deepthi; Rehnström, Karola; Reichenberg, Abraham; Sabo, Aniko; Sachse, Michael; Sanders, Stephan J; Schafer, Chad; Schulte-Rüther, Martin; Skuse, David; Stevens, Christine; Szatmari, Peter; Tammimies, Kristiina; Valladares, Otto; Voran, Annette; Li-San, Wang; Weiss, Lauren A; Willsey, A Jeremy; Yu, Timothy W; Yuen, Ryan K C; Cook, Edwin H; Freitag, Christine M; Gill, Michael; Hultman, Christina M; Lehner, Thomas; Palotie, Aaarno; Schellenberg, Gerard D; Sklar, Pamela; State, Matthew W; Sutcliffe, James S; Walsh, Christiopher A; Scherer, Stephen W; Zwick, Michael E; Barett, Jeffrey C; Cutler, David J; Roeder, Kathryn; Devlin, Bernie; Daly, Mark J; Buxbaum, Joseph D
2014-11-13
The genetic architecture of autism spectrum disorder involves the interplay of common and rare variants and their impact on hundreds of genes. Using exome sequencing, here we show that analysis of rare coding variation in 3,871 autism cases and 9,937 ancestry-matched or parental controls implicates 22 autosomal genes at a false discovery rate (FDR) < 0.05, plus a set of 107 autosomal genes strongly enriched for those likely to affect risk (FDR < 0.30). These 107 genes, which show unusual evolutionary constraint against mutations, incur de novo loss-of-function mutations in over 5% of autistic subjects. Many of the genes implicated encode proteins for synaptic formation, transcriptional regulation and chromatin-remodelling pathways. These include voltage-gated ion channels regulating the propagation of action potentials, pacemaking and excitability-transcription coupling, as well as histone-modifying enzymes and chromatin remodellers-most prominently those that mediate post-translational lysine methylation/demethylation modifications of histones.
Current Concepts of Hyperinflammation in Chronic Granulomatous Disease
Rieber, Nikolaus; Hector, Andreas; Kuijpers, Taco; Roos, Dirk; Hartl, Dominik
2012-01-01
Chronic granulomatous disease (CGD) is the most common inherited disorder of phagocytic functions, caused by genetic defects in the leukocyte nicotinamide dinucleotide phosphate (NADPH) oxidase. Consequently, CGD phagocytes are impaired in destroying phagocytosed microorganisms, rendering the patients susceptible to bacterial and fungal infections. Besides this immunodeficiency, CGD patients suffer from various autoinflammatory symptoms, such as granuloma formation in the skin or urinary tract and Crohn-like colitis. Owing to improved antimicrobial treatment strategies, the majority of CGD patients reaches adulthood, yet the autoinflammatory manifestations become more prominent by lack of causative treatment options. The underlying pathomechanisms driving hyperinflammatory reactions in CGD are poorly understood, but recent studies implicate reduced neutrophil apoptosis and efferocytosis, dysbalanced innate immune receptors, altered T-cell surface redox levels, induction of Th17 cells, the enzyme indolamine-2,3-dioxygenase (IDO), impaired Nrf2 activity, and inflammasome activation. Here we discuss immunological mechanisms of hyperinflammation and their potential therapeutic implications in CGD. PMID:21808651
Tapia, Pablo; Fernández-Galilea, Marta; Robledo, Fermín; Mardones, Pablo; Galgani, José E; Cortés, Víctor A
2018-05-01
The discovery of metabolically active brown adipose tissue (BAT) in adult humans has fuelled the research of diverse aspects of this previously neglected tissue. BAT is solely present in mammals and its clearest physiological role is non-shivering thermogenesis, owing to the capacity of brown adipocytes to dissipate metabolic energy as heat. Recently, a number of other possible functions have been proposed, including direct regulation of glucose and lipid homeostasis and the secretion of a number of factors with diverse regulatory actions. Herein, we review recent advances in general biological knowledge of BAT and discuss the possible implications of this tissue in human metabolic health. In particular, we confront the claimed thermogenic potential of BAT for human energy balance and body mass regulation, mostly based on animal studies, with the most recent quantifications of human BAT. © 2017 Cambridge Philosophical Society.
Implications of genome-wide association studies in cancer therapeutics.
Patel, Jai N; McLeod, Howard L; Innocenti, Federico
2013-09-01
Genome wide association studies (GWAS) provide an agnostic approach to identifying potential genetic variants associated with disease susceptibility, prognosis of survival and/or predictive of drug response. Although these techniques are costly and interpretation of study results is challenging, they do allow for a more unbiased interrogation of the entire genome, resulting in the discovery of novel genes and understanding of novel biological associations. This review will focus on the implications of GWAS in cancer therapy, in particular germ-line mutations, including findings from major GWAS which have identified predictive genetic loci for clinical outcome and/or toxicity. Lessons and challenges in cancer GWAS are also discussed, including the need for functional analysis and replication, as well as future perspectives for biological and clinical utility. Given the large heterogeneity in response to cancer therapeutics, novel methods of identifying mechanisms and biology of variable drug response and ultimately treatment individualization will be indispensable. © 2013 The British Pharmacological Society.
Co-Occurring Disorders in Substance Abuse Treatment: Issues and Prospects
Flynn, Patrick M.; Brown, Barry S.
2008-01-01
This paper explores the epidemiology of co-occurring disorders with an emphasis on the implications of study findings for the functioning and potential of substance abuse treatment. Severity of disorder is discussed as an issue that may have particular significance for the selection of specialized as opposed to traditional substance abuse treatment forms. Exploration is made, as well, of the resources currently available to substance abuse treatment, especially the human resources available, and the implications of resource availability for undertaking initiatives specific to co-occurring disorder. Findings from standard and enhanced treatment for comorbid individuals are examined in an effort to clarify areas of need for specialized and typical treatment personnel. Issues are raised for consideration by the clinical research and treatment provider communities in terms of assessment and diagnosis, manpower and training, and response to the challenge of relapse in this population. PMID:17574791
Synchrony and motor mimicking in chimpanzee observational learning.
Fuhrmann, Delia; Ravignani, Andrea; Marshall-Pescini, Sarah; Whiten, Andrew
2014-06-13
Cumulative tool-based culture underwrote our species' evolutionary success, and tool-based nut-cracking is one of the strongest candidates for cultural transmission in our closest relatives, chimpanzees. However the social learning processes that may explain both the similarities and differences between the species remain unclear. A previous study of nut-cracking by initially naïve chimpanzees suggested that a learning chimpanzee holding no hammer nevertheless replicated hammering actions it witnessed. This observation has potentially important implications for the nature of the social learning processes and underlying motor coding involved. In the present study, model and observer actions were quantified frame-by-frame and analysed with stringent statistical methods, demonstrating synchrony between the observer's and model's movements, cross-correlation of these movements above chance level and a unidirectional transmission process from model to observer. These results provide the first quantitative evidence for motor mimicking underlain by motor coding in apes, with implications for mirror neuron function.
Protein Kinase D1 Signaling in Angiogenic Gene Expression and VEGF-Mediated Angiogenesis.
Ren, Bin
2016-01-01
Protein kinase D 1 (PKD-1) is a signaling kinase important in fundamental cell functions including migration, proliferation, and differentiation. PKD-1 is also a key regulator of gene expression and angiogenesis that is essential for cardiovascular development and tumor progression. Further understanding molecular aspects of PKD-1 signaling in the regulation of angiogenesis may have translational implications in obesity, cardiovascular disease, and cancer. The author will summarize and provide the insights into molecular mechanisms by which PKD-1 regulates transcriptional expression of angiogenic genes, focusing on the transcriptional regulation of CD36 by PKD-1-FoxO1 signaling axis along with the potential implications of this axis in arterial differentiation and morphogenesis. He will also discuss a new concept of dynamic balance between proangiogenic and antiangiogenic signaling in determining angiogenic switch, and stress how PKD-1 signaling regulates VEGF signaling-mediated angiogenesis.
Protein Kinase D1 Signaling in Angiogenic Gene Expression and VEGF-Mediated Angiogenesis
Ren, Bin
2016-01-01
Protein kinase D 1 (PKD-1) is a signaling kinase important in fundamental cell functions including migration, proliferation, and differentiation. PKD-1 is also a key regulator of gene expression and angiogenesis that is essential for cardiovascular development and tumor progression. Further understanding molecular aspects of PKD-1 signaling in the regulation of angiogenesis may have translational implications in obesity, cardiovascular disease, and cancer. The author will summarize and provide the insights into molecular mechanisms by which PKD-1 regulates transcriptional expression of angiogenic genes, focusing on the transcriptional regulation of CD36 by PKD-1-FoxO1 signaling axis along with the potential implications of this axis in arterial differentiation and morphogenesis. He will also discuss a new concept of dynamic balance between proangiogenic and antiangiogenic signaling in determining angiogenic switch, and stress how PKD-1 signaling regulates VEGF signaling-mediated angiogenesis. PMID:27200349
Detection of functional protein domains by unbiased genome-wide forward genetic screening.
Herzog, Mareike; Puddu, Fabio; Coates, Julia; Geisler, Nicola; Forment, Josep V; Jackson, Stephen P
2018-04-18
Establishing genetic and chemo-genetic interactions has played key roles in elucidating mechanisms by which certain chemicals perturb cellular functions. In contrast to gene disruption/depletion strategies to identify mechanisms of drug resistance, searching for point-mutational genetic suppressors that can identify separation- or gain-of-function mutations has been limited. Here, by demonstrating its utility in identifying chemical-genetic suppressors of sensitivity to the DNA topoisomerase I poison camptothecin or the poly(ADP-ribose) polymerase inhibitor olaparib, we detail an approach allowing systematic, large-scale detection of spontaneous or chemically-induced suppressor mutations in yeast or haploid mammalian cells in a short timeframe, and with potential applications in other haploid systems. In addition to applications in molecular biology research, this protocol can be used to identify drug targets and predict drug-resistance mechanisms. Mapping suppressor mutations on the primary or tertiary structures of protein suppressor hits provides insights into functionally relevant protein domains. Importantly, we show that olaparib resistance is linked to missense mutations in the DNA binding regions of PARP1, but not in its catalytic domain. This provides experimental support to the concept of PARP1 trapping on DNA as the prime source of toxicity to PARP inhibitors, and points to a novel olaparib resistance mechanism with potential therapeutic implications.
Grant, Wally; Curthoys, Ian
2017-09-01
Vestibular otolithic organs are recognized as transducers of head acceleration and they function as such up to their corner frequency or undamped natural frequency. It is well recognized that these organs respond to frequencies above their corner frequency up to the 2-3 kHz range (Curthoys et al., 2016). A mechanics model for the transduction of these organs is developed that predicts the response below the undamped natural frequency as an accelerometer and above that frequency as a seismometer. The model is converted to a transfer function using hair cell bundle deflection. Measured threshold acceleration stimuli are used along with threshold deflections for threshold transfer function values. These are compared to model predicted values, both below and above their undamped natural frequency. Threshold deflection values are adjusted to match the model transfer function. The resulting threshold deflection values were well within in measure threshold bundle deflection ranges. Vestibular Evoked Myogenic Potentials (VEMPs) today routinely uses stimulus frequencies of 500 and 1000 Hz, and otoliths have been established incontrovertibly by clinical and neural evidence as the stimulus source. The mechanism for stimulus at these frequencies above the undamped natural frequency of otoliths is presented where otoliths are utilizing a seismometer mode of response for VEMP transduction. Copyright © 2017 Elsevier B.V. All rights reserved.
Carer Appraisal Scale: A Pilot Study of a Novel Carer-Based Assessment of Patient Functioning.
Jeyasingam, Neil
2018-03-01
Measurement of patient outcomes is an integral part of mental health service evaluation, as well as guiding clinical practice to ensure best outcomes for patients. Moreover, carers have long held a need for a voice in care outcomes. Despite there existing numerous tools for quantifying patient functioning based on clinician assessments or self-reports, there is a serious paucity of tools available for the carers of patients to appraise their functioning. This tool, developed for use in a community aged care psychiatric service, involves 4 sections-a global impression of patient progress, a scorable checklist of patient functioning in multiple domains, a qualitative section for identifying the most pressing concerns from the carer's perspective, and an open-ended feedback on treatment to date. In this pilot study, the Carer Appraisal Scale was found to have a fair correlation with the Health of Nation Outcomes Scale for over 65. This tool has potential for use in community aged care psychiatric services, as it provides a framework for communication of concerns, assists in prioritizing care, and adds value to clinician treatment plans, as well as providing another dimension to assessment of the patient while empowering carers in care participation. Practical implications of its use, limitations, and potential for modifications are also discussed.
Corno, Antonio F; Kocica, Mladen J; Torrent-Guasp, Francisco
2006-04-01
The new concepts of cardiac anatomy and physiology, based on the observations made by Francisco Torrent-Guasp's discovery of the helical ventricular myocardial band, can be useful in the context of the surgical strategies currently used to manage patients with congenital heart defects. The potential impact of the Torrent-Guasp's Heart on congenital heart defects have been analyzed in the following settings: ventriculo-arterial discordance (transposition of the great arteries), double (atrio-ventricular and ventriculo-arterial) discordance (congenitally corrected transposition of the great arteries), Ebstein's anomaly, pulmonary valve regurgitation after repair of tetralogy of Fallot, Ross operation, and complex intra-ventricular malformations. The functional interaction of right and left ventricles occurs not only through their arrangements in series but also thanks to the structural spiral features. Changes in size and function of either ventricle may influence the performance of the other ventricle. The variety and complexity of congenital heart defects make the recognition of the relationship between form and function a vital component, especially when compared to acquired disease. The new concepts of cardiac anatomy and function proposed by Francisco Torrent-Guasp, based on his observations, should stimulate further investigations of alternative surgical strategies by individuals involved with the management of patients with congenital heart defects.
NASA Astrophysics Data System (ADS)
Robinson, Georgina; Caldwell, Gary S.; Wade, Matthew J.; Free, Andrew; Jones, Clifford L. W.; Stead, Selina M.
2016-12-01
Deposit-feeding invertebrates are proposed bioremediators in microbial-driven sediment-based aquaculture effluent treatment systems. We elucidate the role of the sediment reduction-oxidation (redox) regime in structuring benthic bacterial communities, having direct implications for bioremediation potential and deposit-feeder nutrition. The sea cucumber Holothuria scabra was cultured on sediments under contrasting redox regimes; fully oxygenated (oxic) and redox stratified (oxic-anoxic). Taxonomically, metabolically and functionally distinct bacterial communities developed between the redox treatments with the oxic treatment supporting the greater diversity; redox regime and dissolved oxygen levels were the main environmental drivers. Oxic sediments were colonised by nitrifying bacteria with the potential to remediate nitrogenous wastes. Percolation of oxygenated water prevented the proliferation of anaerobic sulphate-reducing bacteria, which were prevalent in the oxic-anoxic sediments. At the predictive functional level, bacteria within the oxic treatment were enriched with genes associated with xenobiotics metabolism. Oxic sediments showed the greater bioremediation potential; however, the oxic-anoxic sediments supported a greater sea cucumber biomass. Overall, the results indicate that bacterial communities present in fully oxic sediments may enhance the metabolic capacity and bioremediation potential of deposit-feeder microbial systems. This study highlights the benefits of incorporating deposit-feeding invertebrates into effluent treatment systems, particularly when the sediment is oxygenated.
Robinson, Georgina; Caldwell, Gary S.; Wade, Matthew J.; Free, Andrew; Jones, Clifford L. W.; Stead, Selina M.
2016-01-01
Deposit-feeding invertebrates are proposed bioremediators in microbial-driven sediment-based aquaculture effluent treatment systems. We elucidate the role of the sediment reduction-oxidation (redox) regime in structuring benthic bacterial communities, having direct implications for bioremediation potential and deposit-feeder nutrition. The sea cucumber Holothuria scabra was cultured on sediments under contrasting redox regimes; fully oxygenated (oxic) and redox stratified (oxic-anoxic). Taxonomically, metabolically and functionally distinct bacterial communities developed between the redox treatments with the oxic treatment supporting the greater diversity; redox regime and dissolved oxygen levels were the main environmental drivers. Oxic sediments were colonised by nitrifying bacteria with the potential to remediate nitrogenous wastes. Percolation of oxygenated water prevented the proliferation of anaerobic sulphate-reducing bacteria, which were prevalent in the oxic-anoxic sediments. At the predictive functional level, bacteria within the oxic treatment were enriched with genes associated with xenobiotics metabolism. Oxic sediments showed the greater bioremediation potential; however, the oxic-anoxic sediments supported a greater sea cucumber biomass. Overall, the results indicate that bacterial communities present in fully oxic sediments may enhance the metabolic capacity and bioremediation potential of deposit-feeder microbial systems. This study highlights the benefits of incorporating deposit-feeding invertebrates into effluent treatment systems, particularly when the sediment is oxygenated. PMID:27941918
Suo, Chen; Hrydziuszko, Olga; Lee, Donghwan; Pramana, Setia; Saputra, Dhany; Joshi, Himanshu; Calza, Stefano; Pawitan, Yudi
2015-08-15
Genome and transcriptome analyses can be used to explore cancers comprehensively, and it is increasingly common to have multiple omics data measured from each individual. Furthermore, there are rich functional data such as predicted impact of mutations on protein coding and gene/protein networks. However, integration of the complex information across the different omics and functional data is still challenging. Clinical validation, particularly based on patient outcomes such as survival, is important for assessing the relevance of the integrated information and for comparing different procedures. An analysis pipeline is built for integrating genomic and transcriptomic alterations from whole-exome and RNA sequence data and functional data from protein function prediction and gene interaction networks. The method accumulates evidence for the functional implications of mutated potential driver genes found within and across patients. A driver-gene score (DGscore) is developed to capture the cumulative effect of such genes. To contribute to the score, a gene has to be frequently mutated, with high or moderate mutational impact at protein level, exhibiting an extreme expression and functionally linked to many differentially expressed neighbors in the functional gene network. The pipeline is applied to 60 matched tumor and normal samples of the same patient from The Cancer Genome Atlas breast-cancer project. In clinical validation, patients with high DGscores have worse survival than those with low scores (P = 0.001). Furthermore, the DGscore outperforms the established expression-based signatures MammaPrint and PAM50 in predicting patient survival. In conclusion, integration of mutation, expression and functional data allows identification of clinically relevant potential driver genes in cancer. The documented pipeline including annotated sample scripts can be found in http://fafner.meb.ki.se/biostatwiki/driver-genes/. yudi.pawitan@ki.se Supplementary data are available at Bioinformatics online. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
Time course of clinical change following neurofeedback.
Rance, Mariela; Walsh, Christopher; Sukhodolsky, Denis G; Pittman, Brian; Qiu, Maolin; Kichuk, Stephen A; Wasylink, Suzanne; Koller, William N; Bloch, Michael; Gruner, Patricia; Scheinost, Dustin; Pittenger, Christopher; Hampson, Michelle
2018-05-02
Neurofeedback - learning to modulate brain function through real-time monitoring of current brain state - is both a powerful method to perturb and probe brain function and an exciting potential clinical tool. For neurofeedback effects to be useful clinically, they must persist. Here we examine the time course of symptom change following neurofeedback in two clinical populations, combining data from two ongoing neurofeedback studies. This analysis reveals a shared pattern of symptom change, in which symptoms continue to improve for weeks after neurofeedback. This time course has several implications for future neurofeedback studies. Most neurofeedback studies are not designed to test an intervention with this temporal pattern of response. We recommend that new studies incorporate regular follow-up of subjects for weeks or months after the intervention to ensure that the time point of greatest effect is sampled. Furthermore, this time course of continuing clinical change has implications for crossover designs, which may attribute long-term, ongoing effects of real neurofeedback to the control intervention that follows. Finally, interleaving neurofeedback sessions with assessments and examining when clinical improvement peaks may not be an appropriate approach to determine the optimal number of sessions for an application. Copyright © 2018 Elsevier Inc. All rights reserved.
The tear turnover and tear clearance tests - a review.
Garaszczuk, Izabela K; Montes Mico, Robert; Iskander, D Robert; Expósito, Alejandro Cerviño
2018-03-01
The aim is to provide a summary of methods available for the assessment of tear turnover and tear clearance rates. The review defines tear clearance and tear turnover and describes their implication for ocular surface health. Additionally, it describes main types of techniques for measuring tear turnover, including fluorescein tear clearance tests, techniques utilizing electromagnetic spectrum and tracer molecule and novel experimental techniques utilizing optical coherence tomography and fluorescein profilometry. Areas covered: Internet databases (PubMed, Science Direct, Google Scholar) and most frequently cited references were used as a principal resource of information on tear turnover rate and tear clearance rate, presenting methodologies and equipment, as well as their definition and implications for the anterior eye surface health and function. Keywords used for data-search were as follows: tear turnover, tear clearance, fluorescein clearance, scintigraphy, fluorophotometry, tear flow, drainage, tear meniscus dynamics, Krehbiel flow and lacrimal functional unit. Expert commentary: After decades, the topic of tear turnover assessment has been reintroduced. Recently, new techniques have been developed to propose less invasive, less time consuming and simpler methodologies for the assessment of tear dynamics that have the potential to be utilized in clinical practice.
The role of the leptin in reproduction.
Cervero, Ana; Domínguez, Francisco; Horcajadas, José A; Quiñonero, Alicia; Pellicer, Antonio; Simón, Carlos
2006-06-01
Since its discovery in 1994, leptin has appeared to be a pleiotrophic hormone, governing energy homeostasis and affecting many tissues in the body. Numerous pieces of evidence have accumulated showing that leptin potentially plays an important role in the control of the reproductive function. This review presents the major concepts for the role of leptin in the modulation of reproductive function. As a marker of the nutritional status, leptin affects the hypothalamo-pituitary-gonadal axis, regulating gonadotrophin-releasing hormone and luteinising hormone secretion, and appears to be a permissive factor in the onset of the puberty. This protein and its receptor have been found in the reproductive tissues, indicating that this system could be also implicated in several processes such as embryo development, implantation and pregnancy. Moreover, disorders of the leptin system have been related to some reproductive pathologies such as pre-eclampsia and polycystic ovary syndrome. However, controversy surrounds several aspects of the action of leptin in reproduction that require a deeper investigation of this system. Results to date suggest that this system could be implicated in important reproductive processes such as embryonic development and implantation. Moreover, understanding the role of leptin might be useful for new treatments in reproductive pathologies.
Understanding attention deficit hyperactivity disorder as a continuum
McLennan, John D.
2016-01-01
Abstract Objective To review research findings that consider whether attention deficit hyperactivity disorder (ADHD) is a discrete entity or whether it is more consistent with an extreme end-of-trait distribution in the population and to then grapple with the potential clinical implications. Quality of evidence Peer-reviewed publications in the past 5 years, drawing from diverse fields (taxonomy, epidemiology, genetics, neurobiology, and neuropsychology), were identified through searches in MEDLINE and PsycINFO. Main message Accumulating research findings are most consistent with a predominately dimensional rather than a qualitatively distinct existence for ADHD. This does not negate the clinical needs of those who have substantial ADHD symptom clusters, nor the risks that such symptoms entail. However, the lack of discontinuity in the distribution of such traits in the population creates great uncertainty as to what thresholds should prompt explicit intervention. Conclusion The implications of this pattern of findings might include the need to de-emphasize categorical conceptualizations of ADHD, produce evidence to better inform risk-benefit ratios of interventions along a spectrum of symptom and functional severity, and more coherently triage and arrange service delivery on the basis of symptom and functional severity rather than artificial diagnostic categorizations. PMID:27965331
Casartelli, Luca; Molteni, Massimo
2014-11-01
The relationships between mirror neurons (MNs) and motor imitation, and its clinical implications in autism spectrum disorder (ASD) have been widely investigated; however, the literature remains—at least partially—controversial. In this review we support a multi-level action understanding model focusing on the mirror-based understanding. We review the functional role of the parieto-frontal MNs (PFMN) network claiming that PFMNs function cannot be limited to imitation nor can imitation be explained solely by the activity of PFMNs. The distinction between movement, motor act and motor action is useful to characterize deeply both act(ion) understanding and imitation of act(ion). A more abstract representation of act(ion) may be crucial for clarifying what, why and how an imitator is imitating. What counts in social interactions is achieving goals: it does not matter which effector or string of motor acts you eventually use for achieving (proximal and distal) goals. Similarly, what counts is the ability to recognize/imitate the style of act(ion) regardless of the way in which it is expressed. We address this crucial point referring to its potential implications in ASD. Copyright © 2014 Elsevier Ltd. All rights reserved.
Matrix metalloproteinases: their biological functions and clinical implications.
Hijova, E
2005-01-01
Matrix metalloproteinases (MMPs), which are also known as matrixins, are proteinases that participate in extracellular matrix remodelling and degradation. Under normal physiological conditions, the activities of MMPs are precisely regulated at the level of transcription, at that of activation of the pro-MMP precursor zymogenes as well as at that of inhibition by endogenous inhibitors (tissue inhibitors of metalloproteinases, TIMPs). Alterations in the regulation of MMP activity are implicated in diseases such as cancer, fibrosis, arthritis and atherosclerosis. The pathological effects of MMPs and TIMPs in cardiovascular diseases involve vascular remodelling, atherosclerotic plaque instability and cardiac remodelling in congestive heart failure or after myocardial infarction. Since excessive tissue remodelling and increased matrix metalloproteinases activity have been demonstrated during atherosclerotic lesion progression (including plaque disruption), MMPs represent a potential target for therapeutic intervention aimed at the modification of vascular pathology by restoring the physiological balance between MMPs and TIMPs. Recent findings suggest that MMPs are also involved in cancer initiation, invasion and metastasis; MMP inhibitors could be considered for evaluation as cancer chemopreventive molecules. This review describes the members of MMP and TIMP families and discusses the structure, function and regulation of MMP activity. (Tab. 1, Ref: 45.)
Functional Implications of the IL-23/IL-17 Immune Axis in Schizophrenia.
Debnath, Monojit; Berk, Michael
2017-12-01
The aetiology of schizophrenia seems to stem from complex interactions amongst environmental, genetic, metabolic, immunologic and oxidative components. Chronic low-grade inflammation has been persistently linked to schizophrenia, and this has primarily been based on the findings derived from Th1/Th2 cytokine balance. While the IL-23/IL-17 axis plays crucial role in the pathogenesis of several immune-mediated disorders, it has remained relatively unexplored in neuropsychiatric disorders. Altered levels of cytokines related to IL-23/IL-17 axis have been observed in schizophrenia patients in a few studies. In addition, other indirect factors known to confer schizophrenia risk like complement activation and altered gut microbiota are shown to modulate the IL-23/IL-17 axis. These preliminary observations provide crucial clues about the functional implications of IL-23/IL-17 axis in schizophrenia. In this review, an attempt has been made to highlight the biology of IL-23/IL-17 axis and its relevance to schizophrenia risk and pathogenesis. Given the pathogenic potential of the IL-23/IL-17 axis, therapeutic targeting of this axis may be a promising approach to benefit patients suffering from this devastating disorder.
The Role of TAM Family Receptors in Immune Cell Function: Implications for Cancer Therapy
Paolino, Magdalena; Penninger, Josef M.
2016-01-01
The TAM receptor protein tyrosine kinases—Tyro3, Axl, and Mer—are essential regulators of immune homeostasis. Guided by their cognate ligands Growth arrest-specific gene 6 (Gas6) and Protein S (Pros1), these receptors ensure the resolution of inflammation by dampening the activation of innate cells as well as by restoring tissue function through promotion of tissue repair and clearance of apoptotic cells. Their central role as negative immune regulators is highlighted by the fact that deregulation of TAM signaling has been linked to the pathogenesis of autoimmune, inflammatory, and infectious diseases. Importantly, TAM receptors have also been associated with cancer development and progression. In a cancer setting, TAM receptors have a dual regulatory role, controlling the initiation and progression of tumor development and, at the same time, the associated anti-tumor responses of diverse immune cells. Thus, modulation of TAM receptors has emerged as a potential novel strategy for cancer treatment. In this review, we discuss our current understanding of how TAM receptors control immunity, with a particular focus on the regulation of anti-tumor responses and its implications for cancer immunotherapy. PMID:27775650
Drug-drug interactions involving lysosomes: mechanisms and potential clinical implications.
Logan, Randall; Funk, Ryan S; Axcell, Erick; Krise, Jeffrey P
2012-08-01
Many commercially available, weakly basic drugs have been shown to be lysosomotropic, meaning they are subject to extensive sequestration in lysosomes through an ion trapping-type mechanism. The extent of lysosomal trapping of a drug is an important therapeutic consideration because it can influence both activity and pharmacokinetic disposition. The administration of certain drugs can alter lysosomes such that their accumulation capacity for co-administered and/or secondarily administered drugs is altered. In this review the authors explore what is known regarding the mechanistic basis for drug-drug interactions involving lysosomes. Specifically, the authors address the influence of drugs on lysosomal pH, volume and lipid processing. Many drugs are known to extensively accumulate in lysosomes and significantly alter their structure and function; however, the therapeutic and toxicological implications of this remain controversial. The authors propose that drug-drug interactions involving lysosomes represent an important potential source of variability in drug activity and pharmacokinetics. Most evaluations of drug-drug interactions involving lysosomes have been performed in cultured cells and isolated tissues. More comprehensive in vivo evaluations are needed to fully explore the impact of this drug-drug interaction pathway on therapeutic outcomes.
Childhood malnutrition and the intestinal microbiome.
Kane, Anne V; Dinh, Duy M; Ward, Honorine D
2015-01-01
Malnutrition contributes to almost half of all deaths in children under the age of 5 y, particularly those who live in resource-constrained areas. Those who survive frequently suffer from long-term sequelae including growth failure and neurodevelopmental impairment. Malnutrition is part of a vicious cycle of impaired immunity, recurrent infections, and worsening malnutrition. Recently, alterations in the gut microbiome have also been strongly implicated in childhood malnutrition. It has been suggested that malnutrition may delay the normal development of the gut microbiota in early childhood or force it toward an altered composition that lacks the required functions for healthy growth and/or increases the risk for intestinal inflammation. This review addresses our current understanding of the beneficial contributions of gut microbiota to human nutrition (and conversely the potential role of changes in that community to malnutrition), the process of acquiring an intestinal microbiome, potential influences of malnutrition on the developing microbiota, and the evidence directly linking alterations in the intestinal microbiome to childhood malnutrition. We review recent studies on the association between alterations in the intestinal microbiome and early childhood malnutrition and discuss them in the context of implications for intervention or prevention of the devastation caused by malnutrition.
McHugh, Neil J; Tansley, Sarah L
2018-04-20
The discovery of novel autoantigen systems related to idiopathic inflammatory myopathies (collectively referred to as myositis) in adults and children has had major implications for the diagnosis and management of this group of diseases across a wide range of medical specialties. Traditionally, autoantibodies found in patients with myositis are described as being myositis-specific autoantibodies (MSAs) or myositis-associated autoantibodies (MAAs), depending on their prevalence in other, related conditions. However, certain MSAs are more closely associated with extramuscular manifestations, such as skin and lung disease, than with myositis itself. It is very rare for more than one MSA to coexist in the same individual, underpinning the potential to use MSAs to precisely define genetic and disease endotypes. Each MSA is associated with a distinctive pattern of disease or phenotype, which has implications for diagnosis and a more personalized approach to therapy. Knowledge of the function and localization of the autoantigenic targets for MSAs has provided key insights into the potential immunopathogenic mechanisms of myositis. In particular, evidence suggests that the alteration of expression of a myositis-related autoantigen by certain environmental influences or oncogenesis could be a pivotal event linking autoantibody generation to the development of disease.
Gress, Ronald E; Miller, Jeffrey S; Battiwalla, Minoo; Bishop, Michael R; Giralt, Sergio A; Hardy, Nancy M; Kröger, Nicolaus; Wayne, Alan S; Landau, Dan A; Wu, Catherine J
2013-11-01
In the National Cancer Institute's Second Workshop on the Biology, Prevention, and Treatment of Relapse after Hematopoietic Stem Cell Transplantation, the Scientific/Educational Session on the Biology of Relapse discussed recent advances in understanding some of the host-, disease-, and transplantation-related contributions to relapse, emphasizing concepts with potential therapeutic implications. Relapse after hematopoietic stem cell transplantation (HSCT) represents tumor escape, from the cytotoxic effects of the conditioning regimen and from immunologic control mediated by reconstituted lymphocyte populations. Factors influencing the biology of the therapeutic graft-versus-malignancy (GVM) effect-and relapse-include conditioning regimen effects on lymphocyte populations and homeostasis, immunologic niches, and the tumor microenvironment; reconstitution of lymphocyte populations and establishment of functional immune competence; and genetic heterogeneity within the malignancy defining potential for clonal escape. Recent developments in T cell and natural killer cell homeostasis and reconstitution are reviewed, with implications for prevention and treatment of relapse, as is the application of modern genome sequencing to defining the biologic basis of GVM, clonal escape, and relapse after HSCT. Published by Elsevier Inc.
SET8 promotes epithelial–mesenchymal transition and confers TWIST dual transcriptional activities
Yang, Fen; Sun, Luyang; Li, Qian; Han, Xiao; Lei, Liandi; Zhang, Hua; Shang, Yongfeng
2012-01-01
SET8 is implicated in transcriptional regulation, heterochromatin formation, genomic stability, cell-cycle progression, and development. As such, it is predicted that SET8 might be involved in the development and progression of tumour. However, whether and how SET8 might be implicated in tumourigenesis is currently unknown. Here, we report that SET8 is physically associated with TWIST, a master regulator of epithelial–mesenchymal transition (EMT). We demonstrated that SET8 and TWIST are functionally interdependent in promoting EMT and enhancing the invasive potential of breast cancer cells in vitro and in vivo. We showed that SET8 acts as a dual epigenetic modifier on the promoters of the TWIST target genes E-cadherin and N-cadherin via its H4K20 monomethylation activity. Significantly, in breast carcinoma samples, SET8 expression is positively correlated with metastasis and the expression of TWIST and N-cadherin and negatively correlated with E-cadherin. Together, our experiments revealed a novel role for SET8 in tumour invasion and metastasis and provide a molecular mechanism underlying TWIST-promoted EMT, suggesting SET8 as a potential target for intervention of the metastasis of breast cancer. PMID:21983900
Childhood Malnutrition and the Intestinal Microbiome Malnutrition and the microbiome
Kane, Anne V.; Dinh, Duy M.; Ward, Honorine D.
2015-01-01
Malnutrition contributes to almost half of all deaths in children under the age of 5 years, particularly those who live in resource-constrained areas. Those who survive frequently suffer from long-term sequelae including growth failure and neurodevelopmental impairment. Malnutrition is part of a vicious cycle of impaired immunity, recurrent infections and worsening malnutrition. Recently, alterations in the gut microbiome have also been strongly implicated in childhood malnutrition. It has been suggested that malnutrition may delay the normal development of the gut microbiota in early childhood or force it towards an altered composition that lacks the required functions for healthy growth and/or increases the risk for intestinal inflammation. This review addresses our current understanding of the beneficial contributions of gut microbiota to human nutrition (and conversely the potential role of changes in that community to malnutrition), the process of acquiring an intestinal microbiome, potential influences of malnutrition on the developing microbiota and the evidence directly linking alterations in the intestinal microbiome to childhood malnutrition. We review recent studies on the association between alterations in the intestinal microbiome and early childhood malnutrition and discuss them in the context of implications for intervention or prevention of the devastation caused by malnutrition. PMID:25356748
Will Global Climate Change Alter Fundamental Human Immune Reactivity: Implications for Child Health?
Swaminathan, Ashwin; Lucas, Robyn M; Harley, David; McMichael, Anthony J
2014-11-11
The human immune system is an interface across which many climate change sensitive exposures can affect health outcomes. Gaining an understanding of the range of potential effects that climate change could have on immune function will be of considerable importance, particularly for child health, but has, as yet, received minimal research attention. We postulate several mechanisms whereby climate change sensitive exposures and conditions will subtly impair aspects of the human immune response, thereby altering the distribution of vulnerability within populations-particularly for children-to infection and disease. Key climate change-sensitive pathways include under-nutrition, psychological stress and exposure to ambient ultraviolet radiation, with effects on susceptibility to infection, allergy and autoimmune diseases. Other climate change sensitive exposures may also be important and interact, either additively or synergistically, to alter health risks. Conducting directed research in this area is imperative as the potential public health implications of climate change-induced weakening of the immune system at both individual and population levels are profound. This is particularly relevant for the already vulnerable children of the developing world, who will bear a disproportionate burden of future adverse environmental and geopolitical consequences of climate change.
Catecholamines and cognition after traumatic brain injury
Jenkins, Peter O.; Mehta, Mitul A.
2016-01-01
Abstract Cognitive problems are one of the main causes of ongoing disability after traumatic brain injury. The heterogeneity of the injuries sustained and the variability of the resulting cognitive deficits makes treating these problems difficult. Identifying the underlying pathology allows a targeted treatment approach aimed at cognitive enhancement. For example, damage to neuromodulatory neurotransmitter systems is common after traumatic brain injury and is an important cause of cognitive impairment. Here, we discuss the evidence implicating disruption of the catecholamines (dopamine and noradrenaline) and review the efficacy of catecholaminergic drugs in treating post-traumatic brain injury cognitive impairments. The response to these therapies is often variable, a likely consequence of the heterogeneous patterns of injury as well as a non-linear relationship between catecholamine levels and cognitive functions. This individual variability means that measuring the structure and function of a person’s catecholaminergic systems is likely to allow more refined therapy. Advanced structural and molecular imaging techniques offer the potential to identify disruption to the catecholaminergic systems and to provide a direct measure of catecholamine levels. In addition, measures of structural and functional connectivity can be used to identify common patterns of injury and to measure the functioning of brain ‘networks’ that are important for normal cognitive functioning. As the catecholamine systems modulate these cognitive networks, these measures could potentially be used to stratify treatment selection and monitor response to treatment in a more sophisticated manner. PMID:27256296
Common and distinct neural targets of treatment: changing brain function in substance addiction.
Konova, Anna B; Moeller, Scott J; Goldstein, Rita Z
2013-12-01
Neuroimaging offers an opportunity to examine the neurobiological effects of therapeutic interventions for human drug addiction. Using activation likelihood estimation, the aim of the current meta-analysis was to quantitatively summarize functional neuroimaging studies of pharmacological and cognitive-based interventions for drug addiction, with an emphasis on their common and distinct neural targets. More exploratory analyses also contrasted subgroups of studies based on specific study and sample characteristics. The ventral striatum, a region implicated in reward, motivation, and craving, and the inferior frontal gyrus and orbitofrontal cortex, regions involved in inhibitory control and goal-directed behavior, were identified as common targets of pharmacological and cognitive-based interventions; these regions were observed when the analysis was limited to only studies that used established or efficacious interventions, and across imaging paradigms and types of addictions. Consistent with theoretical models, cognitive-based interventions were additionally more likely to activate the anterior cingulate cortex, middle frontal gyrus, and precuneus, implicated in self-referential processing, cognitive control, and attention. These results suggest that therapeutic interventions for addiction may target the brain structures that are altered across addictions and identify potential neurobiological mechanisms by which the tandem use of pharmacological and cognitive-based interventions may yield synergistic or complementary effects. These findings could inform the selection of novel functional targets in future treatment development for this difficult-to-treat disorder. Copyright © 2013 Elsevier Ltd. All rights reserved.
Common and distinct neural targets of treatment: changing brain function in substance addiction
Konova, Anna B.; Moeller, Scott J.; Goldstein, Rita Z.
2013-01-01
Neuroimaging offers an opportunity to examine the neurobiological effects of therapeutic interventions for human drug addiction. Using activation likelihood estimation, the aim of the current meta-analysis was to quantitatively summarize functional neuroimaging studies of pharmacological and cognitive-based interventions for drug addiction, with an emphasis on their common and distinct neural targets. More exploratory analyses also contrasted subgroups of studies based on specific study and sample characteristics. The ventral striatum, a region implicated in reward, motivation, and craving, and the inferior frontal gyrus and orbitofrontal cortex, regions involved in inhibitory control goal-directed behavior, were identified as common targets of pharmacological and cognitive-based interventions; these regions were observed when the analysis was limited to only studies that used established or efficacious interventions, and across imaging paradigms and types of addictions. Consistent with theoretical models, cognitive-based interventions were additionally more likely to activate the anterior cingulate cortex, middle frontal gyrus, and precuneus, implicated in self-referential processing, cognitive control, and attention. These results suggest that therapeutic interventions for addiction may target the brain structures that are altered across addictions and identify potential neurobiological mechanisms by which the tandem use of pharmacological and cognitive-based interventions may yield synergistic or complementary effects. These findings could inform the selection of novel functional targets in future treatment development for this difficult-to-treat disorder. PMID:24140399
Kwenda, Stanford; Birch, Paul R J; Moleleki, Lucy N
2016-08-11
Long noncoding RNAs (lncRNAs) represent a class of RNA molecules that are implicated in regulation of gene expression in both mammals and plants. While much progress has been made in determining the biological functions of lncRNAs in mammals, the functional roles of lncRNAs in plants are still poorly understood. Specifically, the roles of long intergenic nocoding RNAs (lincRNAs) in plant defence responses are yet to be fully explored. In this study, we used strand-specific RNA sequencing to identify 1113 lincRNAs in potato (Solanum tuberosum) from stem tissues. The lincRNAs are expressed from all 12 potato chromosomes and generally smaller in size compared to protein-coding genes. Like in other plants, most potato lincRNAs possess single exons. A time-course RNA-seq analysis between a tolerant and a susceptible potato cultivar showed that 559 lincRNAs are responsive to Pectobacterium carotovorum subsp. brasiliense challenge compared to mock-inoculated controls. Moreover, coexpression analysis revealed that 17 of these lincRNAs are highly associated with 12 potato defence-related genes. Together, these results suggest that lincRNAs have potential functional roles in potato defence responses. Furthermore, this work provides the first library of potato lincRNAs and a set of novel lincRNAs implicated in potato defences against P. carotovorum subsp. brasiliense, a member of the soft rot Enterobacteriaceae phytopathogens.
Smith, Andrew J; Campbell, Ransom W; Harrison, Patti Kelly; Harrison, David W
2016-01-01
The current case study presents a 43 year old African American woman admitted to a Tertiary Care Rehabilitation unit at a major medical center for concerns over left-sided anesthesia and weakness. Head scans indicate a right middle cerebral arterial distribution infarct altering blood flow in temporal, parietal, and occipital regions in the right cerebral hemisphere. Physician and therapist reports (i.e., speech and occupational therapists) referred the patient for a neuropsychological evaluation for concerns over the patient's capacity to recognize the severity of her deficits and self-care, with potential rule-outs indicated by the extant literature on right CVA for anosognosia, anosodiaphoria, and left hemibody/hemispace neglect. The current case integrates interdisciplinary physician notation, magnetic resonance imaging and magnetic resonance angiogram, observations and reports from speech and occupational therapy, and neuropsychological assessment via standardized tests and neurobehavioral syndrome analysis. Evidence was found for co-occurring syndromes of moderate anosognosia, anosodiaphoria, and left hemibody/hemispatial neglect derived from shared functional cerebral space with overlapping temporal, parietal, and occipital damage. Clinical implications are discussed, including recommendations for therapy approaches based on functional cerebral space theory that may indicate the use of known techniques (e.g., for left hemibody neglect) that may also have therapeutic implications for treating other, more mercurial co-occurring syndromes of anosognosia and anosodiaphoria.
ERIC Educational Resources Information Center
Nam, Sang S.; Hwang, Young S.
2016-01-01
A literature review was conducted to describe important concepts involved in functional analysis of verbal behavior as well as to evaluate empirical research findings on acquisition of picture exchange-based vs. signed mands to suggest instructional implications for teachers and therapists to teach functional communication skills to children with…
Cheng, Wei; Rolls, Edmund T; Gu, Huaguang; Zhang, Jie; Feng, Jianfeng
2015-05-01
Whole-brain voxel-based unbiased resting state functional connectivity was analysed in 418 subjects with autism and 509 matched typically developing individuals. We identified a key system in the middle temporal gyrus/superior temporal sulcus region that has reduced cortical functional connectivity (and increased with the medial thalamus), which is implicated in face expression processing involved in social behaviour. This system has reduced functional connectivity with the ventromedial prefrontal cortex, which is implicated in emotion and social communication. The middle temporal gyrus system is also implicated in theory of mind processing. We also identified in autism a second key system in the precuneus/superior parietal lobule region with reduced functional connectivity, which is implicated in spatial functions including of oneself, and of the spatial environment. It is proposed that these two types of functionality, face expression-related, and of one's self and the environment, are important components of the computations involved in theory of mind, whether of oneself or of others, and that reduced connectivity within and between these regions may make a major contribution to the symptoms of autism. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain.
Secrétan, Philippe-Henri; Karoui, Maher; Bernard, Mélisande; Ghermani, Noureddine; Safta, Fathi; Yagoubi, Najet; Do, Bernard
2016-11-30
Argatroban (ARGA), used as intravenous anticoagulant drug, has been reported to photodegrade under light exposure, requiring specific precautions at handling, storage and administration. Thus, for the first time, aqueous ARGA photodegradation under aerobic conditions has been described in terms of photoproducts, phototransformation processes and potential implications. ARGA significant photoproducts were successfully separated and characterized by gradient reversed-phase liquid chromatography coupled with high-resolution multistage mass spectrometry (LC/HR-MS n ). Hitherto still not available in literature, ARGA in-depth fragmentation study was conducted so as to thoroughly sort out the main mechanisms specific to the molecule and therefore, to propose a fragmentation pattern relevant to the identification of ARGA related substances. Thereafter, in view of the structural characteristics of the photoproducts formed, ARGA photodegradation pathways could be worked out, showing that whether by direct photolysis or through photosensitization, the methyltetrahydroquinoline nitrogen and that of guanidine group would be mainly involved in photolysis initiation reactions, through one-electron oxidation along with proton loss. Desulfonation, cyclisation affording compounds of diazinane type, and/or rearrangements with transfer of the methyltetrahydroquinoline group toward the guanidine function were observed accordingly. Having a good insight into ARGA photodegradation pathways allows for consistent measures in view of mitigating or avoiding the drug decay and the related potential effects. Copyright © 2016 Elsevier B.V. All rights reserved.
Functional age as an indicator of reservoir senescence
Miranda, Leandro E.; Krogman, R. M.
2015-01-01
It has been conjectured that reservoirs differ in the rate at which they manifest senescence, but no attempt has been made to find an indicator of senescence that performs better than chronological age. We assembled an indicator of functional age by creating a multimetric scale consisting of 10 metrics descriptive of reservoir environments that were expected to change directionally with reservoir senescence. In a sample of 1,022 U.S. reservoirs, chronological age was not correlated with functional age. Functional age was directly related to percentage of cultivated land in the catchment and inversely related to reservoir depth. Moreover, aspects of reservoir fishing quality and fish population characteristics were related to functional age. A multimetric scale to indicate reservoir functional age presents the possibility for management intervention from multiple angles. If a reservoir is functionally aging at an accelerated rate, action may be taken to remedy the conditions contributing most to functional age. Intervention to reduce scores of selected metrics in the scale can potentially reduce the rate of senescence and increase the life expectancy of the reservoir. This leads to the intriguing implication that steps can be taken to reduce functional age and actually make the reservoir grow younger.
Noh, Hyun Ji; Tang, Ruqi; Flannick, Jason; O'Dushlaine, Colm; Swofford, Ross; Howrigan, Daniel; Genereux, Diane P; Johnson, Jeremy; van Grootheest, Gerard; Grünblatt, Edna; Andersson, Erik; Djurfeldt, Diana R; Patel, Paresh D; Koltookian, Michele; M Hultman, Christina; Pato, Michele T; Pato, Carlos N; Rasmussen, Steven A; Jenike, Michael A; Hanna, Gregory L; Stewart, S Evelyn; Knowles, James A; Ruhrmann, Stephan; Grabe, Hans-Jörgen; Wagner, Michael; Rück, Christian; Mathews, Carol A; Walitza, Susanne; Cath, Daniëlle C; Feng, Guoping; Karlsson, Elinor K; Lindblad-Toh, Kerstin
2017-10-17
Obsessive-compulsive disorder is a severe psychiatric disorder linked to abnormalities in glutamate signaling and the cortico-striatal circuit. We sequenced coding and regulatory elements for 608 genes potentially involved in obsessive-compulsive disorder in human, dog, and mouse. Using a new method that prioritizes likely functional variants, we compared 592 cases to 560 controls and found four strongly associated genes, validated in a larger cohort. NRXN1 and HTR2A are enriched for coding variants altering postsynaptic protein-binding domains. CTTNBP2 (synapse maintenance) and REEP3 (vesicle trafficking) are enriched for regulatory variants, of which at least six (35%) alter transcription factor-DNA binding in neuroblastoma cells. NRXN1 achieves genome-wide significance (p = 6.37 × 10 -11 ) when we include 33,370 population-matched controls. Our findings suggest synaptic adhesion as a key component in compulsive behaviors, and show that targeted sequencing plus functional annotation can identify potentially causative variants, even when genomic data are limited.Obsessive-compulsive disorder (OCD) is a neuropsychiatric disorder with symptoms including intrusive thoughts and time-consuming repetitive behaviors. Here Noh and colleagues identify genes enriched for functional variants associated with increased risk of OCD.
CRISPR: express delivery to any DNA address.
Peterson, A
2017-01-01
The sudden emergence and worldwide adoption of CRISPR gene-editing technology confronts humanity with unprecedented opportunities and choices. CRISPR's transformative impact on our future understanding of biology, along with its potential to unleash control over the most fundamental of biological processes, is predictable by already achieved applications. Although its origin, composition, and function were revealed only recently, close to 3000 CRISPR-based publications have appeared including insightful and diversely focused reviews referenced here. Adding further to scientific and public awareness, a recent symposium addressed the ethical implications of interfacing CRISPR technology and human biology. However, the magnitude of CRISPR's rapidly emerging power mandates its broadest assessment. Only with the participation of a diverse and informed community can the most effective and humanity-positive CRISPR applications be defined. This brief review is aimed at those with little previous exposure to the CRISPR revolution. The molecules that constitute CRISPR's core components and their functional organization are described along with how the mechanism has been harnessed to edit genome structure and modulate gene function. Additionally, a glimpse into CRISPR's potential to unleash genetic changes with far-reaching consequences is presented. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Cao, Yang; Zhang, Hongxia; Jin, Yifan; Zhang, Yihe; Hayford, Frank
2018-01-01
The human gut is densely populated with diverse microbial communities that are essential to health. Prebiotics and fiber have been shown to possess the ability to modulate the gut microbiota. One of the plants being considered as a potential source of prebiotic is yacon. Yacon is an underutilized plant consumed as a traditional root-based fruit in South America. Yacon mainly contains fructooligosaccharides (FOS) and inulin. Therefore, it has bifidogenic benefits for gut health, because FOS are not easily broken down by digestive enzymes. Bioactive chemical compounds and extracts isolated from yacon have been studied for their various nutrigenomic properties, including as a prebiotic for intestinal health and their antimicrobial and antioxidant effects. This article reviewed scientific studies regarding the bioactive chemical compounds and nutrigenomic properties of extracts and isolated compounds from yacon. These findings may help in further research to investigate yacon-based nutritional products. Yacon can be considered a potential prebiotic source and a novel functional food. However, more detailed epidemiological, animal, and human clinical studies, particularly mechanism-based and phytopharmacological studies, are lacking for the development of evidence-based functional food products. PMID:29649123
Cao, Yang; Ma, Zheng Feei; Zhang, Hongxia; Jin, Yifan; Zhang, Yihe; Hayford, Frank
2018-04-12
The human gut is densely populated with diverse microbial communities that are essential to health. Prebiotics and fiber have been shown to possess the ability to modulate the gut microbiota. One of the plants being considered as a potential source of prebiotic is yacon. Yacon is an underutilized plant consumed as a traditional root-based fruit in South America. Yacon mainly contains fructooligosaccharides (FOS) and inulin. Therefore, it has bifidogenic benefits for gut health, because FOS are not easily broken down by digestive enzymes. Bioactive chemical compounds and extracts isolated from yacon have been studied for their various nutrigenomic properties, including as a prebiotic for intestinal health and their antimicrobial and antioxidant effects. This article reviewed scientific studies regarding the bioactive chemical compounds and nutrigenomic properties of extracts and isolated compounds from yacon. These findings may help in further research to investigate yacon-based nutritional products. Yacon can be considered a potential prebiotic source and a novel functional food. However, more detailed epidemiological, animal, and human clinical studies, particularly mechanism-based and phytopharmacological studies, are lacking for the development of evidence-based functional food products.
2016-01-01
Learning and memory are crucial functions which enable insect pollinators to efficiently locate and extract floral rewards. Exposure to pesticides or infection by parasites may cause subtle but ecologically important changes in cognitive functions of pollinators. The potential interactive effects of these stressors on learning and memory have not yet been explored. Furthermore, sensitivity to stressors may differ between species, but few studies have compared responses in different species. Here, we show that chronic exposure to field-realistic levels of the neonicotinoid clothianidin impaired olfactory learning acquisition in honeybees, leading to potential impacts on colony fitness, but not in bumblebees. Infection by the microsporidian parasite Nosema ceranae slightly impaired learning in honeybees, but no interactive effects were observed. Nosema did not infect bumblebees (3% infection success). Nevertheless, Nosema-treated bumblebees had a slightly lower rate of learning than controls, but faster learning in combination with neonicotinoid exposure. This highlights the potential for complex interactive effects of stressors on learning. Our results underline that one cannot readily extrapolate findings from one bee species to others. This has important implications for regulatory risk assessments which generally use honeybees as a model for all bees. PMID:27053744
Blood biomarkers for brain injury: What are we measuring?
Kawata, Keisuke; Liu, Charles Y.; Merkel, Steven F.; Ramirez, Servio H.; Tierney, Ryan T.; Langford, Dianne
2016-01-01
Accurate diagnosis for mild traumatic brain injury (mTBI) remains challenging, as prognosis and return-to-play/work decisions are based largely on patient reports. Numerous investigations have identified and characterized cellular factors in the blood as potential biomarkers for TBI, in the hope that these factors may be used to gauge the severity of brain injury. None of these potential biomarkers have advanced to use in the clinical setting. Some of the most extensively studied blood biomarkers for TBI include S100β, neuron-specific enolase, glial fibrillary acidic protein, and Tau. Understanding the biological function of each of these factors may be imperative to achieve progress in the field. We address the basic question: what are we measuring? This review will discuss blood biomarkers in terms of cellular origin, normal and pathological function, and possible reasons for increased blood levels. Considerations in the selection, evaluation, and validation of potential biomarkers will also be addressed, along with mechanisms that allow brain-derived proteins to enter the bloodstream after TBI. Lastly, we will highlight perspectives and implications for repetitive neurotrauma in the field of blood biomarkers for brain injury. PMID:27181909
The emerging functions of UCP2 in health, disease, and therapeutics.
Mattiasson, Gustav; Sullivan, Patrick G
2006-01-01
The uncoupling proteins (UCPs) are attracting an increased interest as potential therapeutic targets in a number of important diseases. UCP2 is expressed in several tissues, but its physiological functions as well as potential therapeutic applications are still unclear. Unlike UCP1, UCP2 does not seem to be important to thermogenesis or weight control, but appears to have an important role in the regulation of production of reactive oxygen species, inhibition of inflammation, and inhibition of cell death. These are central features in, for example, neurodegenerative and cardiovascular disease, and experimental evidence suggests that an increased expression and activity of UCP2 in models of these diseases has a beneficial effect on disease progression, implicating a potential therapeutic role for UCP2. UCP2 has an important role in the pathogenesis of type 2 diabetes by inhibiting insulin secretion in islet beta cells. At the same time, type 2 diabetes is associated with increased risk of cardiovascular disease and atherosclerosis where an increased expression of UCP2 appears to be beneficial. This illustrates that therapeutic applications involving UCP2 likely will have to regulate expression and activity in a tissue-specific manner.
Buono, Frank D; Griffiths, Mark D; Sprong, Matthew E; Lloyd, Daniel P; Sullivan, Ryan M; Upton, Thomas D
2017-12-01
Background Internet gaming disorder (IGD) was introduced in the DSM-5 as a way of identifying and diagnosing problematic video game play. However, the use of the diagnosis is constrained, as it shares criteria with other addictive orders (e.g., pathological gambling). Aims Further work is required to better understand IGD. One potential avenue of investigation is IGD's relationship to the primary reinforcing behavioral functions. This study explores the relationship between duration of video game play and the reinforcing behavioral functions that may motivate or maintain video gaming. Methods A total of 499 video game players began the online survey, with complete data from 453 participants (85% white and 28% female), were analyzed. Individuals were placed into five groups based on self-reported hours of video gaming per week, and completed the Video Game Functional Assessment - Revised (VGFA-R). Results The results demonstrated the escape and social attention function were significant in predicting duration of video game play, whereas sensory and tangible were not significant. Conclusion Future implications of the VGFA-R and behaviorally based research are discussed.
Kiang, Michael; Light, Gregory A; Prugh, Jocelyn; Coulson, Seana; Braff, David L; Kutas, Marta
2007-07-01
A hallmark of schizophrenia is impaired proverb interpretation, which could be due to: (1) aberrant activation of disorganized semantic associations, or (2) working memory (WM) deficits. We assessed 18 schizophrenia patients and 18 normal control participants on proverb interpretation, and evaluated these two hypotheses by examining within patients the correlations of proverb interpretation with disorganized symptoms and auditory WM, respectively. Secondarily, we also explored the relationships between proverb interpretation and a spectrum of cognitive functions including auditory sensory-memory encoding (as indexed by the mismatch negativity (MMN) event-related brain potential (ERP)); executive function; and social/occupational function. As expected, schizophrenia patients produced less accurate and less abstract descriptions of proverbs than did controls. These proverb interpretation difficulties in patients were not significantly correlated with disorganization or other symptom factors, but were significantly correlated (p < .05) with WM impairment, as well as with impairments in sensory-memory encoding, executive function, and social/occupational function. These results offer no support for disorganized associations in abnormal proverb interpretation in schizophrenia, but implicate WM deficits, perhaps as a part of a syndrome related to generalized frontal cortical dysfunction.
Functional and clinical neuroanatomy of morality.
Fumagalli, Manuela; Priori, Alberto
2012-07-01
Morality is among the most sophisticated features of human judgement, behaviour and, ultimately, mind. An individual who behaves immorally may violate ethical rules and civil rights, and may threaten others' individual liberty, sometimes becoming violent and aggressive. In recent years, neuroscience has shown a growing interest in human morality, and has advanced our understanding of the cognitive and emotional processes involved in moral decisions, their anatomical substrates and the neurology of abnormal moral behaviour. In this article, we review research findings that have provided a key insight into the functional and clinical neuroanatomy of the brain areas involved in normal and abnormal moral behaviour. The 'moral brain' consists of a large functional network including both cortical and subcortical anatomical structures. Because morality is a complex process, some of these brain structures share their neural circuits with those controlling other behavioural processes, such as emotions and theory of mind. Among the anatomical structures implicated in morality are the frontal, temporal and cingulate cortices. The prefrontal cortex regulates activity in subcortical emotional centres, planning and supervising moral decisions, and when its functionality is altered may lead to impulsive aggression. The temporal lobe is involved in theory of mind and its dysfunction is often implicated in violent psychopathy. The cingulate cortex mediates the conflict between the emotional and the rational components of moral reasoning. Other important structures contributing to moral behaviour include the subcortical nuclei such as the amygdala, hippocampus and basal ganglia. Brain areas participating in moral processing can be influenced also by genetic, endocrine and environmental factors. Hormones can modulate moral behaviour through their effects on the brain. Finally, genetic polymorphisms can predispose to aggressivity and violence, arguing for a genetic-based predisposition to morality. Because abnormal moral behaviour can arise from both functional and structural brain abnormalities that should be diagnosed and treated, the neurology of moral behaviour has potential implications for clinical practice and raises ethical concerns. Last, since research has developed several neuromodulation techniques to improve brain dysfunction (deep brain stimulation, transcranial magnetic stimulation and transcranial direct current stimulation), knowing more about the 'moral brain' might help to develop novel therapeutic strategies for neurologically based abnormal moral behaviour.
Lochhead, Jeffrey J; Ronaldson, Patrick T; Davis, Thomas P
2017-07-01
A functional blood-brain barrier (BBB) is necessary to maintain central nervous system (CNS) homeostasis. Many diseases affecting the CNS, however, alter the functional integrity of the BBB. It has been shown that various diseases and physiological stressors can impact the BBB's ability to selectively restrict passage of substances from the blood to the brain. Modifications of the BBB's permeability properties can potentially contribute to the pathophysiology of CNS diseases and result in altered brain delivery of therapeutic agents. Hypoxia and/or inflammation are central components of a number of diseases affecting the CNS. A number of studies indicate hypoxia or inflammatory pain increase BBB paracellular permeability, induce changes in the expression and/or localization of tight junction proteins, and affect CNS drug uptake. In this review, we look at what is currently known with regard to BBB disruption following a hypoxic or inflammatory insult in vivo. Potential mechanisms involved in altering tight junction components at the BBB are also discussed. A more detailed understanding of the mediators involved in changing BBB functional integrity in response to hypoxia or inflammatory pain could potentially lead to new treatments for CNS diseases with hypoxic or inflammatory components. Additionally, greater insight into the mechanisms involved in TJ rearrangement at the BBB may lead to novel strategies to pharmacologically increase delivery of drugs to the CNS.
House, Carrie D.; Vaske, Charles J.; Schwartz, Arnold M.; Obias, Vincent; Frank, Bryan; Luu, Truong; Sarvazyan, Narine; Irby, Rosalyn; Strausberg, Robert L.; Hales, Tim G.; Stuart, Joshua M.; Lee, Norman H.
2010-01-01
Voltage-gated Na+ channels (VGSCs) have been implicated in the metastatic potential of human breast, prostate and lung cancer cells. Specifically, the SCN5A gene encoding the VGSC isotype Nav1.5 has been defined as a key driver of human cancer cell invasion. In this study, we examined the expression and function of VGSCs in a panel of colon cancer cell lines by electrophysiological recordings. Na+ channel activity and invasive potential were inhibited pharmacologically by tetrodotoxin or genetically by siRNAs specifically targeting SCN5A. Clinical relevance was established by immunohistochemistry of patient biopsies, where there was strong Nav1.5 protein staining in colon cancer specimens but little to no staining in matched-paired normal colon tissues. We explored the mechanism of VGSC-mediated invasive potential on the basis of reported links between VGSC activity and gene expression in excitable cells. Probabilistic modeling of loss-of-function screens and microarray data established an unequivocal role of VGSC SCN5A as a high level regulator of a colon cancer invasion network, involving genes that encompass Wnt signaling, cell migration, ectoderm development, response to biotic stimulus, steroid metabolic process and cell cycle control. siRNA-mediated knockdown of predicted downstream network components caused a loss of invasive behavior, demonstrating network connectivity and its function in driving colon cancer invasion. PMID:20651255
The eukaryotic genome is structurally and functionally more like a social insect colony than a book.
Qiu, Guo-Hua; Yang, Xiaoyan; Zheng, Xintian; Huang, Cuiqin
2017-11-01
Traditionally, the genome has been described as the 'book of life'. However, the metaphor of a book may not reflect the dynamic nature of the structure and function of the genome. In the eukaryotic genome, the number of centrally located protein-coding sequences is relatively constant across species, but the amount of noncoding DNA increases considerably with the increase of organismal evolutional complexity. Therefore, it has been hypothesized that the abundant peripheral noncoding DNA protects the genome and the central protein-coding sequences in the eukaryotic genome. Upon comparison with the habitation, sociality and defense mechanisms of a social insect colony, it is found that the genome is similar to a social insect colony in various aspects. A social insect colony may thus be a better metaphor than a book to describe the spatial organization and physical functions of the genome. The potential implications of the metaphor are also discussed.
Soluble NKG2D ligands: prevalence, release, and functional impact.
Salih, Helmut Rainer; Holdenrieder, Stefan; Steinle, Alexander
2008-05-01
Natural Killer (NK) cells are capable to recognize and eliminate malignant cells. Anti-tumor responses of NK cells are promoted by the tumor-associated expression of cell stress-inducible ligands of the activating NK receptor NKG2D. Current evidence suggests that established tumors subvert NKG2D-mediated tumor immunosurveillance by releasing NKG2D ligands (NKG2DL). Release of NKG2DL has been observed in a broad variety of human tumor entities and is thought to interfere with NKG2D-mediated tumor immunity in several ways. Further, levels of soluble NKG2DL (sNKG2DL) were also found to be elevated under various non-malignant conditions, although the functional implications remain largely unclear. Here we review and discuss the available data on the prevalence, release, functional impact, and potential clinical value of sNKG2DL.
Gutwinski, Stefan; Schreiter, Stefanie; Priller, Josef; Henssler, Jonathan; Wiers, Corinde E; Heinz, Andreas
2017-09-26
Regular alcohol consumption affects cognitive performance and the development of dementia. So far, findings are contradicting, which might be explained in part by dose-related effects. For this narrative review, we undertook a literature search for surveys investigating the impact of alcohol consumption on cognitive performance and the development of dementia. The majority of studies observed a U-shaped relationship between regular alcohol consumption and cognitive function: frequent heavy consumption of alcohol alters brain functions and decreases cognitive performance; regular light and moderate consumption may have protective impact. In many studies, total abstainers show an inferior cognitive performance than people with moderate or light consumption. Nevertheless, policy implications are difficult to draw for at least 2 reasons: (1) the possible risks associated with alcohol consumption and (2) the potential confounders in the group of non-consumers and heavy consumers. © Georg Thieme Verlag KG Stuttgart · New York.
NASA Astrophysics Data System (ADS)
Dholabhai, Pratik; Atta-Fynn, Raymond; Ray, Asok
2008-03-01
Ab initio total energy calculations within the framework of density functional theory have been performed for atomic hydrogen and oxygen chemisorptions on the (0001) surface of double hexagonal packed americium using a full-potential all-electron linearized augmented plane wave plus local orbitals (FLAPW+lo) method. The three-fold hollow hcp site was found to be the most stable site for H adsorption, while the two-fold bridge adsorption site was found to be the most stable site for O adsorption. Chemisorption energies and adsorption geometries for different adsorption sites will be discussed. The change in work functions, magnetic moments, partial charges inside muffin-tins, difference charge density distributions and density of states for the bare Am slab and the Am slab after adsorption of the adatom will be discussed. The implications of chemisorption on Am 5f electron localization-delocalization will also be discussed.
Reliability of real-time ultrasound for the assessment of transversus abdominis function.
Kidd, Adrian W; Magee, Scott; Richardson, Carolyn A
2002-07-01
Transversus abdominis (TrA) has now been established as a key muscle for the stabilization of the lumbar spine and sacroiliac joints. Significantly, dysfunction of this muscle has also been implicated in low back pain. Real-time ultrasound (US) is a non-invasive procedure that has the potential to evaluate objectively the function of TrA. To investigate M-mode US as a reliable method of assessing TrA function. M-mode US was used to measure the width of TrA as subjects drew in their lower abdominal wall at a controlled speed to a target depth. Eleven subjects were imaged. the measures of TrA width were reliable and ranged between 3.14mm relaxed and 6.35mm contracted. The standard error of measurement ranged between 0.18mm and 0.57mm. M-mode US provides a reliable non-invasive measure of a controlled contraction of TrA.
NASA Astrophysics Data System (ADS)
Ciompi, Luc
At variance with a purely cognitivistic approach, an affect-centered model of mental functioning called `fractal affect-logic' is presented on the basis of current emotional-psychological and neurobiological research. Functionally integrated feeling-thinking-behaving programs generated by action appear in this model as the basic `building blocks' of the psyche. Affects are understood as the essential source of energy that mobilises and organises both linear and nonlinear affective-cognitive dynamics, under the influence of appropriate control parameters and order parameters. Global patterns of affective-cognitive functioning form dissipative structures in the sense of Prigogine, with affect-specific attractors and repulsors, bifurcations, high sensitivity for initial conditions and a fractal overall structure that may be represented in a complex potential landscape of variable configuration. This concept opens new possibilities of understanding normal and pathological psychodynamics and sociodynamics, with numerous practical and theoretical implications.
Neuronal Lipid Metabolism: Multiple Pathways Driving Functional Outcomes in Health and Disease
Tracey, Timothy J.; Steyn, Frederik J.; Wolvetang, Ernst J.; Ngo, Shyuan T.
2018-01-01
Lipids are a fundamental class of organic molecules implicated in a wide range of biological processes related to their structural diversity, and based on this can be broadly classified into five categories; fatty acids, triacylglycerols (TAGs), phospholipids, sterol lipids and sphingolipids. Different lipid classes play major roles in neuronal cell populations; they can be used as energy substrates, act as building blocks for cellular structural machinery, serve as bioactive molecules, or a combination of each. In amyotrophic lateral sclerosis (ALS), dysfunctions in lipid metabolism and function have been identified as potential drivers of pathogenesis. In particular, aberrant lipid metabolism is proposed to underlie denervation of neuromuscular junctions, mitochondrial dysfunction, excitotoxicity, impaired neuronal transport, cytoskeletal defects, inflammation and reduced neurotransmitter release. Here we review current knowledge of the roles of lipid metabolism and function in the CNS and discuss how modulating these pathways may offer novel therapeutic options for treating ALS. PMID:29410613
The MPS1 family of protein kinases.
Liu, Xuedong; Winey, Mark
2012-01-01
MPS1 protein kinases are found widely, but not ubiquitously, in eukaryotes. This family of potentially dual-specific protein kinases is among several that regulate a number of steps of mitosis. The most widely conserved MPS1 kinase functions involve activities at the kinetochore in both the chromosome attachment and the spindle checkpoint. MPS1 kinases also function at centrosomes. Beyond mitosis, MPS1 kinases have been implicated in development, cytokinesis, and several different signaling pathways. Family members are identified by virtue of a conserved C-terminal kinase domain, though the N-terminal domain is quite divergent. The kinase domain of the human enzyme has been crystallized, revealing an unusual ATP-binding pocket. The activity, level, and subcellular localization of Mps1 family members are tightly regulated during cell-cycle progression. The mitotic functions of Mps1 kinases and their overexpression in some tumors have prompted the identification of Mps1 inhibitors and their active development as anticancer drugs.
Emerging Common Molecular Pathways for Primary Dystonia
LeDoux, Mark S; Dauer, William T; Warner, Thomas T
2013-01-01
Background The dystonias are a group of hyperkinetic movement disorders whose principal cause is neuron dysfunction at one or more interconnected nodes of the motor system. The study of genes and proteins which cause familial dystonia provides critical information about the cellular pathways involved in this dysfunction which disrupts the motor pathways at systems level. In recent years study of the increasing number of DYT genes has implicated a number of cell functions which appear to be involved in the pathogenesis of dystonia. Methods Review of literature published in English language publications available on Pubmed relating to the genetics and cellular pathology of dystonia Results and Conclusions Numerous potential pathogenetic mechanisms have been identified. We describe those which fall into three emerging thematic groups: cell cycle and transcriptional regulation in the nucleus, endoplasmic reticulum and nuclear envelope function, and control of synaptic function. PMID:23893453
Bacopa monnieri as an Antioxidant Therapy to Reduce Oxidative Stress in the Aging Brain
Simpson, Tamara; Pase, Matthew; Stough, Con
2015-01-01
The detrimental effect of neuronal cell death due to oxidative stress and mitochondrial dysfunction has been implicated in age-related cognitive decline and neurodegenerative disorders such as Alzheimer's disease. The Indian herb Bacopa monnieri is a dietary antioxidant, with animal and in vitro studies indicating several modes of action that may protect the brain against oxidative damage. In parallel, several studies using the CDRI08 extract have shown that extracts of Bacopa monnieri improve cognitive function in humans. The biological mechanisms of this cognitive enhancement are unknown. In this review we discuss the animal studies and in vivo evidence for Bacopa monnieri as a potential therapeutic antioxidant to reduce oxidative stress and improve cognitive function. We suggest that future studies incorporate neuroimaging particularly magnetic resonance spectroscopy into their randomized controlled trials to better understand whether changes in antioxidant status in vivo cause improvements in cognitive function. PMID:26413126
Hybrid Functional Study of Sodium and Potassium Incorporation in Cu2ZnSnS4
NASA Astrophysics Data System (ADS)
Tse, Kin Fai; Wong, Manhoi; Zhang, Yiou; Zhang, Jingzhao; Zhu, Junyi
The thermodynamics of Na and K incorporation and its effects in Cu2ZnSnS4 (CZTS) is studied using density functional theory with hybrid functional. The allowed chemical potential of Na/K in CZTS is established. Formation energy calculations shows that Na can be significantly incorporated as both substitutional defects and interstitial defects, and incorporation of K related defects are generally less favorable. Transition energy calculations is performed showing that both Na and K exhibit benign defect properties and act as a p-type dopant. The qualitative disagreement between GGA with rigid band edge shifting and HSE calculations, formation of defect complexes, and implications in experiment will also be discussed. The understandings on the defect properties of Na and K provides an essential knowledge to further understand the surfactant effects of Na and K observed in experiments. This work is supported by General Research Fund Ref. No: 14319416.
Long Non-Coding RNA as Potential Biomarker for Prostate Cancer: Is It Making a Difference?
Deng, Junli; Tang, Jie; Wang, Guo; Zhu, Yuan-Shan
2017-03-07
Whole genome transcriptomic analyses have identified numerous long non-coding RNA (lncRNA) transcripts that are increasingly implicated in cancer biology. LncRNAs are found to promote essential cancer cell functions such as proliferation, invasion, and metastasis, with the potential to serve as novel biomarkers of various cancers and to further reveal uncharacterized aspects of tumor biology. However, the biological and molecular mechanisms as well as the clinical applications of lncRNAs in diverse diseases are not completely understood, and remain to be fully explored. LncRNAs may be critical players and regulators in prostate cancer carcinogenesis and progression, and could serve as potential biomarkers for prostate cancer. This review focuses on lncRNA biomarkers that are already available for clinical use and provides an overview of lncRNA biomarkers that are under investigation for clinical development in prostate cancer.
Civil Uses of Remotely Piloted Aircraft
NASA Technical Reports Server (NTRS)
Aderhold, J. R.; Gordon, G.; Scott, G. W.
1976-01-01
The technology effort is identified and assessed that is required to bring the civil uses of RPVs to fruition and to determine whether or not the potential market is real and economically practical, the technologies are within reach, the operational problems are manageable, and the benefits are worth the cost. To do so, the economic, technical, and environmental implications are examined. The time frame is 1980-85. Representative uses are selected; detailed functional and performance requirements are derived for RPV systems; and conceptual system designs are devised. Total system cost comparisons are made with non-RPV alternatives. The potential market demand for RPV systems is estimated. Environmental and safety requirements are examined, and legal and regulatory concerns are identified. A potential demand for 2,000-11,000 RPV systems is estimated. Typical cost savings of 25-35% compared to non-RPV alternatives are determined. There appear to be no environmental problems, and the safety issue appears manageable.
Gate-Sensing the Potential Landscape of a GaAs Two-Dimensional Electron Gas
NASA Astrophysics Data System (ADS)
Croot, Xanthe; Mahoney, Alice; Pauka, Sebastian; Colless, James; Reilly, David; Watson, John; Fallahi, Saeed; Gardner, Geoff; Manfra, Michael; Lu, Hong; Gossard, Arthur
In situ dispersive gate sensors hold potential as a means of enabling the scalable readout of quantum dot arrays. Sensitive to quantum capacitance, dispersive sensors have been used to detect inter- and intra-dot transitions in GaAs double quantum dots, and can distinguish the spin states of singlet triplet qubits. In addition, the gate-sensing technique is likely of value in probing the physics of Majorana zero modes in nanowire devices. Beyond the readout signatures associated with charge and spin configurations of qubits, gate-sensing is sensitive to trapped charge in the potential landscape. Here, we report gate-sensing signals arising from tunnelling of electrons between puddles of trapped charge in a GaAs 2DEG. We examine these signals in a family of different devices with varying mobilities, and as a function of temperature and bias. Implications for qubit readout using the gate-sensing technique are discussed.
Three critical questions for future research on lesbian relationships.
Diamond, Lisa M
2017-01-02
In this article I discuss three questions that should be priorities for future research on lesbian love and relationships. The first question concerns the very definition of "lesbian relationship," given how many women may be engaged in same-sex relationships without identifying as lesbian. The second question concerns the potential influence of childhood neglect and abuse on adult women's same-sex relationships, a topic that has important implications for both psychological well-being and relationship functioning. The third question concerns the potential downsides of legal marriage for women's same-sex relationships, a topic that is particularly important in light of the newfound legal recognition of same-sex marriage in all 50 states. Although there are many understudied questions in the domain of women's same-sex relationships, research on these three questions has particularly strong potential to advance our understanding of lesbian love and relationships in important ways.
Coarse graining of NN inelastic interactions up to 3 GeV: Repulsive versus structural core
NASA Astrophysics Data System (ADS)
Fernández-Soler, P.; Ruiz Arriola, E.
2017-07-01
The repulsive short-distance core is one of the main paradigms of nuclear physics which even seems confirmed by QCD lattice calculations. On the other hand nuclear potentials at short distances are motivated by high energy behavior where inelasticities play an important role. We analyze NN interactions up to 3 GeV in terms of simple coarse grained complex and energy dependent interactions. We discuss two possible and conflicting scenarios which share the common feature of a vanishing wave function at the core location in the particular case of S waves. We find that the optical potential with a repulsive core exhibits a strong energy dependence whereas the optical potential with the structural core is characterized by a rather adiabatic energy dependence which allows one to treat inelasticity perturbatively. We discuss the possible implications for nuclear structure calculations of both alternatives.
Optimized nested Markov chain Monte Carlo sampling: theory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coe, Joshua D; Shaw, M Sam; Sewell, Thomas D
2009-01-01
Metropolis Monte Carlo sampling of a reference potential is used to build a Markov chain in the isothermal-isobaric ensemble. At the endpoints of the chain, the energy is reevaluated at a different level of approximation (the 'full' energy) and a composite move encompassing all of the intervening steps is accepted on the basis of a modified Metropolis criterion. By manipulating the thermodynamic variables characterizing the reference system we maximize the average acceptance probability of composite moves, lengthening significantly the random walk made between consecutive evaluations of the full energy at a fixed acceptance probability. This provides maximally decorrelated samples ofmore » the full potential, thereby lowering the total number required to build ensemble averages of a given variance. The efficiency of the method is illustrated using model potentials appropriate to molecular fluids at high pressure. Implications for ab initio or density functional theory (DFT) treatment are discussed.« less
Genome Editing Redefines Precision Medicine in the Cardiovascular Field
Lahm, Harald; Dreßen, Martina; Lange, Rüdiger; Wu, Sean M.; Krane, Markus
2018-01-01
Genome editing is a powerful tool to study the function of specific genes and proteins important for development or disease. Recent technologies, especially CRISPR/Cas9 which is characterized by convenient handling and high precision, revolutionized the field of genome editing. Such tools have enormous potential for basic science as well as for regenerative medicine. Nevertheless, there are still several hurdles that have to be overcome, but patient-tailored therapies, termed precision medicine, seem to be within reach. In this review, we focus on the achievements and limitations of genome editing in the cardiovascular field. We explore different areas of cardiac research and highlight the most important developments: (1) the potential of genome editing in human pluripotent stem cells in basic research for disease modelling, drug screening, or reprogramming approaches and (2) the potential and remaining challenges of genome editing for regenerative therapies. Finally, we discuss social and ethical implications of these new technologies. PMID:29731778
Barch, Deanna M; Treadway, Michael T; Schoen, Nathan
2014-05-01
One of the most debilitating aspects of schizophrenia is an apparent interest in or ability to exert effort for rewards. Such "negative symptoms" may prevent individuals from obtaining potentially beneficial outcomes in educational, occupational, or social domains. In animal models, dopamine abnormalities decrease willingness to work for rewards, implicating dopamine (DA) function as a candidate substrate for negative symptoms given that schizophrenia involves dysregulation of the dopamine system. We used the effort-expenditure for rewards task (EEfRT) to assess the degree to which individuals with schizophrenia were wiling to exert increased effort for either larger magnitude rewards or for rewards that were more probable. Fifty-nine individuals with schizophrenia and 39 demographically similar controls performed the EEfRT task, which involves making choices between "easy" and "hard" tasks to earn potential rewards. Individuals with schizophrenia showed less of an increase in effort allocation as either reward magnitude or probability increased. In controls, the frequency of choosing the hard task in high reward magnitude and probability conditions was negatively correlated with depression severity and anhedonia. In schizophrenia, fewer hard task choices were associated with more severe negative symptoms and worse community and work function as assessed by a caretaker. Consistent with patterns of disrupted dopamine functioning observed in animal models of schizophrenia, these results suggest that 1 mechanism contributing to impaired function and motivational drive in schizophrenia may be a reduced allocation of greater effort for higher magnitude or higher probability rewards.
Heyes, Susan M; Bond, Malcolm J; Harrington, Ann; Belan, Ingrid
2016-09-01
Bladder cancer is a genitourinary disease of increasing incidence. Despite improvements in treatment, outcomes remain equivocal with high recurrence rates. It is associated with poor psychosocial outcomes due to reduced functioning of the genitourinary system. The objective of these analyses was to query whether reported loss of function or the perception of psychological burden caused by this functional impedance was the key to understanding psychosocial outcomes. The sample comprised 119 participants with a confirmed diagnosis of bladder cancer. They completed a self-report questionnaire comprising the Bladder Cancer Index, Mini-mental Adjustment to Cancer Scale, Psychosocial Adjustment to Illness Scale and standard sociodemographic details. Simple mediation and serial mediation were used to explore the potential for psychological burden to mediate associations between loss of function and cognitive distress, and the potential additional contribution of positive partner support on these relationships. Age and duration of cancer were considered as covariates. Simple mediation demonstrated that the association between function and cognitive distress was fully mediated by perceived psychological burden. Serial mediation, which allowed for the addition of partner support, again demonstrated full mediation, with partner support being the key predictive variable. These analyses emphasise the importance of an appreciation of individuals' interpretation of the burden occasioned by bladder cancer and the role of a supportive partner. The implications for management discussions and support services in alleviating negative psychological outcomes in bladder cancer are highlighted. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Stage-dependent piRNAs in chicken implicated roles in modulating male germ cell development.
Chang, Kai-Wei; Tseng, Yen-Tzu; Chen, Yi-Chen; Yu, Chih-Yun; Liao, Hung-Fu; Chen, Yi-Chun; Tu, Yu-Fan Evan; Wu, Shinn-Chih; Liu, I-Hsuan; Pinskaya, Marina; Morillon, Antonin; Pain, Bertrand; Lin, Shau-Ping
2018-06-01
The PIWI/piRNA pathway is a conserved machinery important for germ cell development and fertility. This piRNA-guided molecular machinery is best known for repressing derepressed transposable elements (TE) during epigenomic reprogramming. The extent to which piRNAs are involved in modulating transcripts beyond TEs still need to be clarified, and it may be a stage-dependent event. We chose chicken germline as a study model because of the significantly lower TE complexity in the chicken genome compared to mammalian species. We generated high-confidence piRNA candidates in various stages across chicken germline development by 3'-end-methylation-enriched small RNA sequencing and in-house bioinformatics analysis. We observed a significant developmental stage-dependent loss of TE association and a shifting of the ping-pong cycle signatures. Moreover, the stage-dependent reciprocal abundance of LINE retrotransposons, CR1-C, and its associated piRNAs implicated the developmental stage-dependent role of piRNA machinery. The stage dependency of piRNA expression and its potential functions can be better addressed by analyzing the piRNA precursors/clusters. Interestingly, the new piRNA clusters identified from embryonic chicken testes revealed evolutionary conservation between chickens and mammals, which was previously thought to not exist. In this report, we provided an original chicken RNA resource and proposed an analytical methodology that can be used to investigate stage-dependent changes in piRNA compositions and their potential roles in TE regulation and beyond, and also revealed possible conserved functions of piRNAs in developing germ cells.
Spieler, Derek; Kaffe, Maria; Knauf, Franziska; Bessa, José; Tena, Juan J; Giesert, Florian; Schormair, Barbara; Tilch, Erik; Lee, Heekyoung; Horsch, Marion; Czamara, Darina; Karbalai, Nazanin; von Toerne, Christine; Waldenberger, Melanie; Gieger, Christian; Lichtner, Peter; Claussnitzer, Melina; Naumann, Ronald; Müller-Myhsok, Bertram; Torres, Miguel; Garrett, Lillian; Rozman, Jan; Klingenspor, Martin; Gailus-Durner, Valérie; Fuchs, Helmut; Hrabě de Angelis, Martin; Beckers, Johannes; Hölter, Sabine M; Meitinger, Thomas; Hauck, Stefanie M; Laumen, Helmut; Wurst, Wolfgang; Casares, Fernando; Gómez-Skarmeta, Jose Luis; Winkelmann, Juliane
2014-04-01
Genome-wide association studies (GWAS) identified the MEIS1 locus for Restless Legs Syndrome (RLS), but causal single nucleotide polymorphisms (SNPs) and their functional relevance remain unknown. This locus contains a large number of highly conserved noncoding regions (HCNRs) potentially functioning as cis-regulatory modules. We analyzed these HCNRs for allele-dependent enhancer activity in zebrafish and mice and found that the risk allele of the lead SNP rs12469063 reduces enhancer activity in the Meis1 expression domain of the murine embryonic ganglionic eminences (GE). CREB1 binds this enhancer and rs12469063 affects its binding in vitro. In addition, MEIS1 target genes suggest a role in the specification of neuronal progenitors in the GE, and heterozygous Meis1-deficient mice exhibit hyperactivity, resembling the RLS phenotype. Thus, in vivo and in vitro analysis of a common SNP with small effect size showed allele-dependent function in the prospective basal ganglia representing the first neurodevelopmental region implicated in RLS.
The Insula: A ‘Hub of Activity’ in Migraine
Borsook, David; Veggeberg, Rosanna; Erpelding, Nathalie; Borra, Ronald; Linnman, Clas; Burstein, Rami; Becerra, Lino
2017-01-01
The insula, a ‘cortical hub’ buried within the lateral sulcus, is involved in a number of processes including goal-directed cognition, conscious awareness, autonomic regulation, interoception and somatosensation. While some of these processes are well known in the clinical presentation of migraine (i.e., autonomic and somatosensory alterations), other more complex behaviors in migraine, such as conscious awareness and error detection, are less well described. Since the insula processes and relays afferent inputs from brain areas involved in these functions to areas involved in higher cortical function such as frontal, temporal and parietal regions, it may be implicated as a brain region that translates the signals of altered internal milieu in migraine, along with other chronic pain conditions, through the insula into complex behaviors. Here we review how the insula function and structure is altered in migraine. As a brain region of a number of brain functions, it may serve as a model to study new potential clinical perspectives for migraine treatment. PMID:26290446
The sacroiliac joint: an overview of its anatomy, function and potential clinical implications.
Vleeming, A; Schuenke, M D; Masi, A T; Carreiro, J E; Danneels, L; Willard, F H
2012-12-01
This article focuses on the (functional) anatomy and biomechanics of the pelvic girdle and specifically the sacroiliac joints (SIJs). The SIJs are essential for effective load transfer between the spine and legs. The sacrum, pelvis and spine, and the connections to the arms, legs and head, are functionally interrelated through muscular, fascial and ligamentous interconnections. A historical overview is presented on pelvic and especially SIJ research, followed by a general functional anatomical overview of the pelvis. In specific sections, the development and maturation of the SIJ is discussed, and a description of the bony anatomy and sexual morphism of the pelvis and SIJ is debated. The literature on the SIJ ligaments and innervation is discussed, followed by a section on the pathology of the SIJ. Pelvic movement studies are investigated and biomechanical models for SIJ stability analyzed, including examples of insufficient versus excessive sacroiliac force closure. © 2012 The Authors. Journal of Anatomy © 2012 Anatomical Society.
The evolutionary landscape of intergenic trans-splicing events in insects
Kong, Yimeng; Zhou, Hongxia; Yu, Yao; Chen, Longxian; Hao, Pei; Li, Xuan
2015-01-01
To explore the landscape of intergenic trans-splicing events and characterize their functions and evolutionary dynamics, we conduct a mega-data study of a phylogeny containing eight species across five orders of class Insecta, a model system spanning 400 million years of evolution. A total of 1,627 trans-splicing events involving 2,199 genes are identified, accounting for 1.58% of the total genes. Homology analysis reveals that mod(mdg4)-like trans-splicing is the only conserved event that is consistently observed in multiple species across two orders, which represents a unique case of functional diversification involving trans-splicing. Thus, evolutionarily its potential for generating proteins with novel function is not broadly utilized by insects. Furthermore, 146 non-mod trans-spliced transcripts are found to resemble canonical genes from different species. Trans-splicing preserving the function of ‘breakup' genes may serve as a general mechanism for relaxing the constraints on gene structure, with profound implications for the evolution of genes and genomes. PMID:26521696
Gap junctional communication in the male reproductive system.
Pointis, Georges; Fiorini, Céline; Defamie, Norah; Segretain, Dominique
2005-12-20
Male fertility is a highly controlled process that allows proliferation, meiosis and differentiation of male germ cells in the testis, final maturation in the epididymis and also requires functional male accessory glands: seminal vesicles, prostate and corpus cavernosum. In addition to classical endocrine and paracrine controls, mainly by gonadotropins LH and FSH and steroids, there is now strong evidence that all these processes are dependent upon the presence of homocellular or heterocellular junctions, including gap junctions and their specific connexins (Cxs), between the different cell types that structure the male reproductive tract. The present review is focused on the identification of Cxs, their distribution in the testis and in different structures of the male genital tract (epididymis, seminal vesicle, prostate, corpus cavernosum), their crucial role in the control of spermatogenesis and their implication in the function of the male accessory glands, including functional smooth muscle tone. Their potential dysfunctions in some testis (spermatogenic arrest, seminoma) and prostate (benign hyperplasia, adenocarcinoma) diseases and in the physiopathology of the human erectile function are also discussed.
Komar, Carolyn M
2005-01-01
The peroxisome proliferator-activated receptors (PPARs) are a family of transcription factors involved in varied and diverse processes such as steroidogenesis, angiogenesis, tissue remodeling, cell cycle, apoptosis, and lipid metabolism. These processes are critical for normal ovarian function, and all three PPAR family members – alpha, delta, and gamma, are expressed in the ovary. Most notably, the expression of PPARgamma is limited primarily to granulosa cells in developing follicles, and is regulated by luteinizing hormone (LH). Although much has been learned about the PPARs since their initial discovery, very little is known regarding their function in ovarian tissue. This review highlights what is known about the roles of PPARs in ovarian cells, and discusses potential mechanisms by which PPARs could influence ovarian function. Because PPARs are activated by drugs currently in clinical use (fibrates and thiazolidinediones), it is important to understand their role in the ovary, and how manipulation of their activity may impact ovarian physiology as well as ovarian pathology. PMID:16131403
Long Noncoding RNAs: Past, Present, and Future
Kung, Johnny T. Y.; Colognori, David; Lee, Jeannie T.
2013-01-01
Long noncoding RNAs (lncRNAs) have gained widespread attention in recent years as a potentially new and crucial layer of biological regulation. lncRNAs of all kinds have been implicated in a range of developmental processes and diseases, but knowledge of the mechanisms by which they act is still surprisingly limited, and claims that almost the entirety of the mammalian genome is transcribed into functional noncoding transcripts remain controversial. At the same time, a small number of well-studied lncRNAs have given us important clues about the biology of these molecules, and a few key functional and mechanistic themes have begun to emerge, although the robustness of these models and classification schemes remains to be seen. Here, we review the current state of knowledge of the lncRNA field, discussing what is known about the genomic contexts, biological functions, and mechanisms of action of lncRNAs. We also reflect on how the recent interest in lncRNAs is deeply rooted in biology’s longstanding concern with the evolution and function of genomes. PMID:23463798
Cai, Yin; Kandula, Vidya; Kosuru, Ramoji; Ye, Xiaodong; Irwin, Michael G; Xia, Zhengyuan
2017-10-02
Mammalian Rap1, the most conserved telomere-interacting protein, beyond its role within nucleus for the maintenance of telomeric functions, is also well known for its pleiotropic functions in various physiological and pathological conditions associated with metabolism, inflammation and oxidative stress. For all these, nowadays Rap1 is the subject of critical investigations aimed to unveil its molecular signaling pathways and to scrutinize the applicability of its modulation as a promising therapeutic strategy with clinical relevance. However, the underlying intimate mechanisms of Rap1 are not extensively studied, but any modulation of this protein level has been associated with pathologies like inflammation, oxidative stress and deregulated metabolism. This is considerably important in light of the recent discovery of Rap1 modulation in diseases like cancer and cardiac metabolic disorders. In this review, we focus on both the telomeric and nontelomeric functions of Rap1 and its modulation in various health risks, especially on the heart.
Banks, Matthew L.
2017-01-01
Many cathinone analogs act as substrates or inhibitors at dopamine, norepinephrine, and serotonin transporters (DAT, NET, SERT, respectively). Drug selectivity at DAT vs. SERT is a key determinant of abuse potential for monoamine transporter substrates and inhibitors, such that potency at DAT > SERT is associated with high abuse potential, whereas potency at DAT < SERT is associated with low abuse potential. Quantitative structure—activity relationship (QSAR) studies with a series of 4-substituted methcathinone analogs identified volume of the 4-position substituent on the methcathinone phenyl ring as one structural determinant of both DAT vs. SERT selectivity and abuse-related behavioral effects in an intracranial self-stimulation procedure in rats. Subsequent modeling studies implicated specific amino acids in DAT and SERT that might interact with 4-substituent volume to determine effects produced by this series of cathinone analogs. These studies illustrate use of QSAR analysis to investigate pharmacology of cathinones and function of monoamine transporters. PMID:27696217
ERIC Educational Resources Information Center
Lee, Chi-Ming Angela; Thoma, Stephen J.
2018-01-01
The purpose of this study was to develop and test a scale assessing students' moral thinking and communication (MTC) functioning as well as to explore the implications for moral development and education. The rationale of MTC functioning, including interaction of four independent competencies: moral awareness, moral judgement, moral discourse, and…
Circulating Endocannabinoid Concentrations and Sexual Arousal in Women
Klein, Carolin; Hill, Matthew N.; Chang, Sabrina C.H.; Hillard, Cecilia J.; Gorzalka, Boris B.
2013-01-01
Introduction Several lines of evidence point to the potential role of the endocannabinoid system in female sexual functioning. These include results from studies describing the subjective effects of exogenous cannabinoids on sexual functioning in humans and the observable effects of exogenous cannabinoids on sexual functioning in other species, as well as results from studies investigating the location of cannabinoid receptors in the brain and periphery, and the effects of cannabinoid receptor activation on neurotransmitters implicated in sexual functioning. While these lines of research suggest a role for the endocannabinoid system in female sexual functioning, no studies investigating the relationship between concentrations of endogenous cannabinoids (i.e., arachidonoylethanolamide [AEA] and 2-arachidonoylglycerol [2-AG]) and sexual functioning have been conducted in any species. Aim To measure circulating endocannabinoid concentrations in relation to subjective and physiological indices of sexual arousal in women (n = 21). Methods Serum endocannabinoid (AEA and 2-AG) concentrations were measured immediately prior to, and immediately following, viewing of neutral (control) and erotic (experimental) film stimuli in a repeated measures design. Physiological sexual arousal was measured via vaginal photoplethysmography. Subjective sexual arousal was measured both continuously and non-continuously. Pearson’s correlations were used to investigate the relationships between endocannabinoid concentrations and sexual arousal. Main Outcome Measures Changes in AEA and 2-AG concentrations from pre- to post-film and in relation to physiological and subjective indices of sexual arousal. Results Results revealed a significant relationship between endocannabinoid concentrations and female sexual arousal, whereby increases in both physiological and subjective indices of sexual arousal were significantly associated with decreases in AEA, and increases in subjective indices of sexual arousal were significantly associated with decreases in 2-AG. Conclusions These findings support the hypothesis that the endocannabinoid system is involved in female sexual functioning, with implications for furthering understanding of the biological mechanisms underlying female sexual functioning. PMID:22462722
Uljarević, Mirko; Katsos, Napoleon; Hudry, Kristelle; Gibson, Jenny L
2016-11-01
Language and communication skills are essential aspects of child development, which are often disrupted in children with neurodevelopmental disorders. Cutting edge research in psycholinguistics suggests that multilingualism has potential to influence social, linguistic and cognitive development. Thus, multilingualism has implications for clinical assessment, diagnostic formulation, intervention and support offered to families. We present a systematic review and synthesis of the effects of multilingualism for children with neurodevelopmental disorders and discuss clinical implications. We conducted systematic searches for studies on multilingualism in neurodevelopmental disorders. Keywords for neurodevelopmental disorders were based on Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition categories as follows; Intellectual Disabilities, Communication Disorders, Autism Spectrum Disorder (ASD), Attention-Deficit/Hyperactivity Disorder, Specific Learning Disorder, Motor Disorders, Other Neurodevelopmental Disorders. We included only studies based on empirical research and published in peer-reviewed journals. Fifty studies met inclusion criteria. Thirty-eight studies explored multilingualism in Communication Disorders, 10 in ASD and two in Intellectual Disability. No studies on multilingualism in Specific Learning Disorder or Motor Disorders were identified. Studies which found a disadvantage for multilingual children with neurodevelopmental disorders were rare, and there appears little reason to assume that multilingualism has negative effects on various aspects of functioning across a range of conditions. In fact, when considering only those studies which have compared a multilingual group with developmental disorders to a monolingual group with similar disorders, the findings consistently show no adverse effects on language development or other aspects of functioning. In the case of ASD, a positive effect on communication and social functioning has been observed. There is little evidence to support the widely held view that multilingual exposure is detrimental to the linguistic or social development of individuals with neurodevelopmental disorders. However, we also note that the available pool of studies is small and the number of methodologically high quality studies is relatively low. We discuss implications of multilingualism for clinical management of neurodevelopmental disorders, and discuss possible directions for future research. © 2016 Association for Child and Adolescent Mental Health.
Consciousness, Functional Networks and Delirium Screening.
Eeles, Eamonn; Burianova, Hana; Pandy, Shaun; Pinsker, Donna
2017-01-01
Consciousness, the medium of sentient thought, requires integrity of functional networks and their connectivity. In health, they function as a co-operative but mutually exclusive paradigm of introspection versus external awareness subserved via the Default Mode Network and Task Positive State, respectively. Higher thinking in the conscious state is then segregated according to need. There is research evidence to suggest that functional networks may be impacted in disorders of consciousness and conceptual support for a mechanistic role in delirium. This potentially central aspect of delirium manifestation is relatively unexplored. This article describes the role of disrupted functional networks in delirium. How this relates to current understanding of delirium neurobiology and the ramifications for clinical diagnosis is discussed. A review of the role of functional networks, particularly DMN and TPN, has been undertaken with respect to health and delirium. An exploration of how symptoms of delirium may be related to functional network aberrancy has been undertaken. Implications for research and clinical practice in delirium have been presented. In delirium, a disturbance of consciousness, the DMN is pathologically co-activated and functional cortical connectivity is compromised. The clinical correlate is of an experiential singularity where internal and external drivers become indistinguishable, reality and delusion merge and the notion of self is effaced. Our group propose that functional network disruption in conjunction with cortical disconnectivity is central to the mechanism of delirium. Clinical tools may exploit the neurobiology of delirium to improve its diagnosis and an example of such a simple screening instrument (SQeeC) is provided. Functional networks are critically disrupted in delirium and may be central to clinical features. A better understanding of the neurobiology of delirium will generate research opportunities with potential for therapeutic gains in detection, diagnosis, and management. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Disclosure of Traumas and Immune Function: Health Implications for Psychotherapy.
ERIC Educational Resources Information Center
Pennebaker, James W.; And Others
1988-01-01
Assigned 50 healthy undergraduates the task of writing about either traumatic experiences or superficial topics for four consecutive days. Examination of cellular-immune system function and health center visits suggests that confronting traumatic experiences was physically beneficial. Discusses implications of such active confrontation of…
Hazeldine, Jon; Lord, Janet M
2013-09-01
Forming the first line of defence against virally infected and malignant cells, natural killer (NK) cells are critical effector cells of the innate immune system. With age, significant impairments have been reported in the two main mechanisms by which NK cells confer host protection: direct cytotoxicity and the secretion of immunoregulatory cytokines and chemokines. In elderly subjects, decreased NK cell activity has been shown to be associated with an increased incidence and severity of viral infection, highlighting the clinical implications that age-associated changes in NK cell biology have on the health of older adults. However, is an increased susceptibility to viral infection the only consequence of these age-related changes in NK cell function? Recently, evidence has emerged that has shown that in addition to eliminating transformed cells, NK cells are involved in many other biological processes such as immune regulation, anti-microbial immune responses and the recognition and elimination of senescent cells, novel functions that involve NK-mediated cytotoxicity and/or cytokine production. Thus, the decrease in NK cell function that accompanies physiological ageing is likely to have wider implications for the health of older adults than originally thought. Here, we give a detailed description of the changes in NK cell biology that accompany human ageing and propose that certain features of the ageing process such as: (i) the increased reactivation rates of latent Mycobacterium tuberculosis, (ii) the slower resolution of inflammatory responses and (iii) the increased incidence of bacterial and fungal infection are attributable in part to an age-associated decline in NK cell function. Copyright © 2013 Elsevier B.V. All rights reserved.
Sominsky, Luba; Fuller, Erin A; Bondarenko, Evgeny; Ong, Lin Kooi; Averell, Lee; Nalivaiko, Eugene; Dunkley, Peter R; Dickson, Phillip W; Hodgson, Deborah M
2013-01-01
Neonatal exposure of rodents to an immune challenge alters a variety of behavioural and physiological parameters in adulthood. In particular, neonatal lipopolysaccharide (LPS; 0.05 mg/kg, i.p.) exposure produces robust increases in anxiety-like behaviour, accompanied by persistent changes in hypothalamic-pituitary-adrenal (HPA) axis functioning. Altered autonomic nervous system (ANS) activity is an important physiological contributor to the generation of anxiety. Here we examined the long term effects of neonatal LPS exposure on ANS function and the associated changes in neuroendocrine and behavioural indices. ANS function in Wistar rats, neonatally treated with LPS, was assessed via analysis of tyrosine hydroxylase (TH) in the adrenal glands on postnatal days (PNDs) 50 and 85, and via plethysmographic assessment of adult respiratory rate in response to mild stress (acoustic and light stimuli). Expression of genes implicated in regulation of autonomic and endocrine activity in the relevant brain areas was also examined. Neonatal LPS exposure produced an increase in TH phosphorylation and activity at both PNDs 50 and 85. In adulthood, LPS-treated rats responded with increased respiratory rates to the lower intensities of stimuli, indicative of increased autonomic arousal. These changes were associated with increases in anxiety-like behaviours and HPA axis activity, alongside altered expression of the GABA-A receptor α2 subunit, CRH receptor type 1, CRH binding protein, and glucocorticoid receptor mRNA levels in the prefrontal cortex, hippocampus and hypothalamus. The current findings suggest that in addition to the commonly reported alterations in HPA axis functioning, neonatal LPS challenge is associated with a persistent change in ANS activity, associated with, and potentially contributing to, the anxiety-like phenotype. The findings of this study reflect the importance of changes in the perinatal microbial environment on the ontogeny of physiological processes.
Ashok, A H; Marques, T R; Jauhar, S; Nour, M M; Goodwin, G M; Young, A H; Howes, O D
2017-01-01
Bipolar affective disorder is a common neuropsychiatric disorder. Although its neurobiological underpinnings are incompletely understood, the dopamine hypothesis has been a key theory of the pathophysiology of both manic and depressive phases of the illness for over four decades. The increased use of antidopaminergics in the treatment of this disorder and new in vivo neuroimaging and post-mortem studies makes it timely to review this theory. To do this, we conducted a systematic search for post-mortem, pharmacological, functional magnetic resonance and molecular imaging studies of dopamine function in bipolar disorder. Converging findings from pharmacological and imaging studies support the hypothesis that a state of hyperdopaminergia, specifically elevations in D2/3 receptor availability and a hyperactive reward processing network, underlies mania. In bipolar depression imaging studies show increased dopamine transporter levels, but changes in other aspects of dopaminergic function are inconsistent. Puzzlingly, pharmacological evidence shows that both dopamine agonists and antidopaminergics can improve bipolar depressive symptoms and perhaps actions at other receptors may reconcile these findings. Tentatively, this evidence suggests a model where an elevation in striatal D2/3 receptor availability would lead to increased dopaminergic neurotransmission and mania, whilst increased striatal dopamine transporter (DAT) levels would lead to reduced dopaminergic function and depression. Thus, it can be speculated that a failure of dopamine receptor and transporter homoeostasis might underlie the pathophysiology of this disorder. The limitations of this model include its reliance on pharmacological evidence, as these studies could potentially affect other monoamines, and the scarcity of imaging evidence on dopaminergic function. This model, if confirmed, has implications for developing new treatment strategies such as reducing the dopamine synthesis and/or release in mania and DAT blockade in bipolar depression. PMID:28289283
The adaptive evolution of the mammalian mitochondrial genome
da Fonseca, Rute R; Johnson, Warren E; O'Brien, Stephen J; Ramos, Maria João; Antunes, Agostinho
2008-01-01
Background The mitochondria produce up to 95% of a eukaryotic cell's energy through oxidative phosphorylation. The proteins involved in this vital process are under high functional constraints. However, metabolic requirements vary across species, potentially modifying selective pressures. We evaluate the adaptive evolution of 12 protein-coding mitochondrial genes in 41 placental mammalian species by assessing amino acid sequence variation and exploring the functional implications of observed variation in secondary and tertiary protein structures. Results Wide variation in the properties of amino acids were observed at functionally important regions of cytochrome b in species with more-specialized metabolic requirements (such as adaptation to low energy diet or large body size, such as in elephant, dugong, sloth, and pangolin, and adaptation to unusual oxygen requirements, for example diving in cetaceans, flying in bats, and living at high altitudes in alpacas). Signatures of adaptive variation in the NADH dehydrogenase complex were restricted to the loop regions of the transmembrane units which likely function as protons pumps. Evidence of adaptive variation in the cytochrome c oxidase complex was observed mostly at the interface between the mitochondrial and nuclear-encoded subunits, perhaps evidence of co-evolution. The ATP8 subunit, which has an important role in the assembly of F0, exhibited the highest signal of adaptive variation. ATP6, which has an essential role in rotor performance, showed a high adaptive variation in predicted loop areas. Conclusion Our study provides insight into the adaptive evolution of the mtDNA genome in mammals and its implications for the molecular mechanism of oxidative phosphorylation. We present a framework for future experimental characterization of the impact of specific mutations in the function, physiology, and interactions of the mtDNA encoded proteins involved in oxidative phosphorylation. PMID:18318906
Sominsky, Luba; Fuller, Erin A.; Bondarenko, Evgeny; Ong, Lin Kooi; Averell, Lee; Nalivaiko, Eugene; Dunkley, Peter R.; Dickson, Phillip W.; Hodgson, Deborah M.
2013-01-01
Neonatal exposure of rodents to an immune challenge alters a variety of behavioural and physiological parameters in adulthood. In particular, neonatal lipopolysaccharide (LPS; 0.05 mg/kg, i.p.) exposure produces robust increases in anxiety-like behaviour, accompanied by persistent changes in hypothalamic-pituitary-adrenal (HPA) axis functioning. Altered autonomic nervous system (ANS) activity is an important physiological contributor to the generation of anxiety. Here we examined the long term effects of neonatal LPS exposure on ANS function and the associated changes in neuroendocrine and behavioural indices. ANS function in Wistar rats, neonatally treated with LPS, was assessed via analysis of tyrosine hydroxylase (TH) in the adrenal glands on postnatal days (PNDs) 50 and 85, and via plethysmographic assessment of adult respiratory rate in response to mild stress (acoustic and light stimuli). Expression of genes implicated in regulation of autonomic and endocrine activity in the relevant brain areas was also examined. Neonatal LPS exposure produced an increase in TH phosphorylation and activity at both PNDs 50 and 85. In adulthood, LPS-treated rats responded with increased respiratory rates to the lower intensities of stimuli, indicative of increased autonomic arousal. These changes were associated with increases in anxiety-like behaviours and HPA axis activity, alongside altered expression of the GABA-A receptor α2 subunit, CRH receptor type 1, CRH binding protein, and glucocorticoid receptor mRNA levels in the prefrontal cortex, hippocampus and hypothalamus. The current findings suggest that in addition to the commonly reported alterations in HPA axis functioning, neonatal LPS challenge is associated with a persistent change in ANS activity, associated with, and potentially contributing to, the anxiety-like phenotype. The findings of this study reflect the importance of changes in the perinatal microbial environment on the ontogeny of physiological processes. PMID:23483921
Detecting and characterizing circular RNAs
Jeck, William R.; Sharpless, Norman E.
2014-01-01
Circular RNA transcripts were first identified in the early 1990s but knowledge of these species has remained limited, as their study has been difficult through traditional methods of RNA analysis. Now, novel bioinformatic approaches coupled with biochemical enrichment strategies and deep sequencing have allowed comprehensive studies of circular RNA species. Recent studies have revealed thousands of endogenous circular RNAs (circRNAs) in mammalian cells, some of which are highly abundant and evolutionarily conserved. Evidence is emerging that some circRNAs might regulate microRNA (miRNA) function, and roles in transcriptional control have also been suggested. Therefore, study of this class of non-coding RNAs has potential implications for therapeutic and research applications. We believe the key future challenge to the field will be to understand the regulation and function of these unusual molecules. PMID:24811520
Tetraspanin-enriched microdomains: a functional unit in cell plasma membranes.
Yáñez-Mó, María; Barreiro, Olga; Gordon-Alonso, Mónica; Sala-Valdés, Mónica; Sánchez-Madrid, Francisco
2009-09-01
Membrane lipids and proteins are non-randomly distributed and are unable to diffuse freely in the plane of the membrane. This is because of multiple constraints imposed both by the cortical cytoskeleton and by the preference of lipids and proteins to cluster into diverse and specialized membrane domains, including tetraspanin-enriched microdomains, glycosylphosphatidyl inositol-linked proteins nanodomains and caveolae, among others. Recent biophysical characterization of tetraspanin-enriched microdomains suggests that they might be specially suited for the regulation of avidity of adhesion receptors and the compartmentalization of enzymatic activities. Moreover, modulation by tetraspanins of the function of adhesion receptors involved in inflammation, lymphocyte activation, cancer and pathogen infection suggests potential as therapeutic targets. This review explores this emerging picture of tetraspanin microdomains and discusses the implications for cell adhesion, proteolysis and pathogenesis.
Aging in Two Languages: Implications for Public Health
Bialystok, Ellen; Abutalebi, Jubin; Bak, Thomas H.; Burke, Deborah M.; Kroll, Judith F.
2016-01-01
With the population aging and a dramatic increase in the number of senior citizens, public health systems will be increasingly burdened with the need to deal with the care and treatment of individuals with dementia. We review evidence demonstrating how a particular experience, bilingualism, has been shown to protect cognitive function in older age and delay onset of symptoms of dementia. This paper describes behavioral and brain studies that have compared monolingual and bilingual older adults on measures of cognitive function or brain structure and reviews evidence demonstrating a protective effect of bilingualism against symptoms of dementia. We conclude by presenting some data showing the potential savings in both human costs in terms of demented patients and economic considerations in terms of public money if symptoms of dementia could be postponed. PMID:26993154
Synaptic clustering within dendrites: an emerging theory of memory formation
Kastellakis, George; Cai, Denise J.; Mednick, Sara C.; Silva, Alcino J.; Poirazi, Panayiota
2015-01-01
It is generally accepted that complex memories are stored in distributed representations throughout the brain, however the mechanisms underlying these representations are not understood. Here, we review recent findings regarding the subcellular mechanisms implicated in memory formation, which provide evidence for a dendrite-centered theory of memory. Plasticity-related phenomena which affect synaptic properties, such as synaptic tagging and capture, synaptic clustering, branch strength potentiation and spinogenesis provide the foundation for a model of memory storage that relies heavily on processes operating at the dendrite level. The emerging picture suggests that clusters of functionally related synapses may serve as key computational and memory storage units in the brain. We discuss both experimental evidence and theoretical models that support this hypothesis and explore its advantages for neuronal function. PMID:25576663
Handwriting difficulties in children with autism spectrum disorders: a scoping review.
Kushki, Azadeh; Chau, Tom; Anagnostou, Evdokia
2011-12-01
Functional handwriting involves complex interactions among physical, cognitive and sensory systems. Impairments in many aspects of these systems are associated with Autism spectrum disorders (ASD), suggesting a heightened risk of handwriting difficulties in children with ASD. This scoping review aimed to: (1) survey the existing evidence about potential contributions to compromised handwriting function in children with ASD, and (2) map out the existing studies documenting handwriting difficulties in children with ASD. The current evidence implicates impairments in fine motor control and visual-motor integration as likely contributors to handwriting difficulties in children with ASD, though the role of the latter is not well-understood. Moreover, diminished overall legibility and compromised letter formation are emerging points of convergence among existing studies of handwriting quality in children with ASD.
Chung, ChiHye
2013-08-01
Recent reports have proposed a novel function for the N-methyl-D-aspartate (NMDA) receptor (NMDAR), a well-known excitatory, ionotropic receptor. A series of observations employing pharmacological techniques has proposed that upon ligand binding, this ionotropic receptor can actually function via signaling cascades independent of traditional ionotropic action. Moreover, the "metabotropic" action of NMDARs is suggested to mediate a form of synaptic plasticity, namely long-term synaptic depression (LTD), which shares cellular mechanisms with the synaptic deficits observed in Alzheimer's disease. Given that a growing body of clinical and preclinical evidence strongly recommends NMDAR antagonists for their therapeutic potentials and advantages in a variety of diseases, further investigation into their molecular and cellular mechanisms is required to better understand the "metabotropic" action of NMDARs.
The Hubble flow of plateau inflation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coone, Dries; Roest, Diederik; Vennin, Vincent, E-mail: a.a.coone@rug.nl, E-mail: d.roest@rug.nl, E-mail: vincent.vennin@port.ac.uk
2015-11-01
In the absence of CMB precision measurements, a Taylor expansion has often been invoked to parametrize the Hubble flow function during inflation. The standard ''horizon flow'' procedure implicitly relies on this assumption. However, the recent Planck results indicate a strong preference for plateau inflation, which suggests the use of Padé approximants instead. We propose a novel method that provides analytic solutions of the flow equations for a given parametrization of the Hubble function. This method is illustrated in the Taylor and Padé cases, for low order expansions. We then present the results of a full numerical treatment scanning larger ordermore » expansions, and compare these parametrizations in terms of convergence, prior dependence, predictivity and compatibility with the data. Finally, we highlight the implications for potential reconstruction methods.« less
Leptin regulates bone formation via the sympathetic nervous system
NASA Technical Reports Server (NTRS)
Takeda, Shu; Elefteriou, Florent; Levasseur, Regis; Liu, Xiuyun; Zhao, Liping; Parker, Keith L.; Armstrong, Dawna; Ducy, Patricia; Karsenty, Gerard
2002-01-01
We previously showed that leptin inhibits bone formation by an undefined mechanism. Here, we show that hypothalamic leptin-dependent antiosteogenic and anorexigenic networks differ, and that the peripheral mediators of leptin antiosteogenic function appear to be neuronal. Neuropeptides mediating leptin anorexigenic function do not affect bone formation. Leptin deficiency results in low sympathetic tone, and genetic or pharmacological ablation of adrenergic signaling leads to a leptin-resistant high bone mass. beta-adrenergic receptors on osteoblasts regulate their proliferation, and a beta-adrenergic agonist decreases bone mass in leptin-deficient and wild-type mice while a beta-adrenergic antagonist increases bone mass in wild-type and ovariectomized mice. None of these manipulations affects body weight. This study demonstrates a leptin-dependent neuronal regulation of bone formation with potential therapeutic implications for osteoporosis.
Recent findings and future directions for interpolar mitotic kinesin inhibitors in cancer therapy
Myers, Stephanie M.; Collins, Ian
2016-01-01
The kinesin class of microtubule-associated motor proteins present attractive anti-cancer targets owing to their roles in key functions in dividing cells. Two interpolar mitotic kinesins Eg5 and HSET have opposing motor functions in mitotic spindle assembly with respect to microtubule movement, but both offer opportunities to develop cancer selective therapeutic agents. Here, we summarize the progress to date in developing inhibitors of Eg5 and HSET, with an emphasis on structural biology insights into the binding modes of allosteric inhibitors, compound selectivity and mechanisms of action of different chemical scaffolds. We discuss translation of preclinical studies to clinical experience with Eg5 inhibitors, recent findings on potential resistance mechanisms, and explore the implications for future anticancer drug development against these targets. PMID:26976726
Quantum Stress: Density Functional Theory Formulation and Physical Manifestation
NASA Astrophysics Data System (ADS)
Hu, Hao; Liu, Feng
2012-02-01
The concept of ``quantum stress (QS)'' is introduced and formulated within density functional theory (DFT), to underlie extrinsic electronic effects on the stress state of solids and thin films in the absence of lattice strain. An explicit expression of QS (σ^Q) is derived in relation to the deformation potential of electronic states (ξ) and the variation of electron density (δn), σ^Q=ξ(δn), as a quantum analog of classical Hook's law. Two distinct QS manifestations are demonstrated quantitatively by DFT calculations: (1) in the form of bulk stress induced by charge carriers; and (2) in the form of surface stress induced by quantum confinement. QS has broad implications in physical phenomena and technological applications that are based on coupling of electronic structure with lattice strain.
The mere exposure effect in patients with schizophrenia.
Marie, A; Gabrieli, J D; Vaidya, C; Brown, B; Pratto, F; Zajonc, R B; Shaw, R J
2001-01-01
The mere exposure effect refers to the development of an emotional preference for previously unfamiliar material because of frequent exposure to that material. This study compared schizophrenia subjects (n = 20) to normal controls (n = 21) to determine whether implicit memory, as demonstrated by the mere exposure effect, was intact. Patients with schizophrenia demonstrated a normal preference for both verbal and visual materials seen earlier relative to novel materials, despite impaired performance on a recognition task for explicit memory using similar materials. Previous studies of schizophrenia subjects have shown a dissociation between implicit and explicit memory on verbal tasks. We found a similar dissociation demonstrated by normal functioning on an implicit memory task and impaired functioning on an explicit memory task. Potential implications of these findings are discussed with regard to treatment and rehabilitation.
Importance of β-defensins in sperm function.
Dorin, Julia R; Barratt, Christopher L R
2014-09-01
Recent work in humans and mouse has confirmed the involvement of the host defence β-defensin peptides in male fertility. We discuss here the work that has implicated β-defensins in sperm function including the identification of the epididymis as the predominant site of expression of the peptides and the in vivo consequences of mutation and deletion. The potential dual role of these peptides in the regulation of infection and control of sperm maturation is compelling and may combine their antimicrobial activity with the ability of these molecules to interact with cell membrane receptors and modulate ion transport. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Recent findings and future directions for interpolar mitotic kinesin inhibitors in cancer therapy.
Myers, Stephanie M; Collins, Ian
2016-01-01
The kinesin class of microtubule-associated motor proteins present attractive anticancer targets owing to their roles in key functions in dividing cells. Two interpolar mitotic kinesins Eg5 and HSET have opposing motor functions in mitotic spindle assembly with respect to microtubule movement, but both offer opportunities to develop cancer selective therapeutic agents. Here, we summarize the progress to date in developing inhibitors of Eg5 and HSET, with an emphasis on structural biology insights into the binding modes of allosteric inhibitors, compound selectivity and mechanisms of action of different chemical scaffolds. We discuss translation of preclinical studies to clinical experience with Eg5 inhibitors, recent findings on potential resistance mechanisms and explore the implications for future anticancer drug development against these targets.
Gain-of-function experiments: time for a real debate.
Duprex, W Paul; Fouchier, Ron A M; Imperiale, Michael J; Lipsitch, Marc; Relman, David A
2015-01-01
According to the WHO, dual use research of concern (DURC) is "life sciences research that is intended for benefit, but which might easily be misapplied to do harm". Recent studies, particularly those on influenza viruses, have led to renewed attention on DURC, as there is an ongoing debate over whether the benefits of gain-of-function (GOF) experiments that result in an increase in the transmission and/or pathogenicity of potential pandemic pathogens (PPPs) are outweighed by concerns over biosecurity and biosafety. In this Viewpoint article, proponents and opponents of GOF experiments discuss the benefits and risks associated with these studies, as well as the implications of the current debate for the scientific community and the general public, and suggest how the current discussion should move forward.
Implications of causality for quantum biology - I: topology change
NASA Astrophysics Data System (ADS)
Scofield, D. F.; Collins, T. C.
2018-06-01
A framework for describing the causal, topology changing, evolution of interacting biomolecules is developed. The quantum dynamical manifold equations (QDMEs) derived from this framework can be related to the causality restrictions implied by a finite speed of light and to Planck's constant to set a transition frequency scale. The QDMEs imply conserved stress-energy, angular-momentum and Noether currents. The functional whose extremisation leads to this result provides a causal, time-dependent, non-equilibrium generalisation of the Hohenberg-Kohn theorem. The system of dynamical equations derived from this functional and the currents J derived from the QDMEs are shown to be causal and consistent with the first and second laws of thermodynamics. This has the potential of allowing living systems to be quantum mechanically distinguished from non-living ones.
Symmetrization in jellyfish: reorganization to regain function, and not lost parts.
Abrams, Michael J; Goentoro, Lea
2016-02-01
We recently reported a previously unidentified strategy of self-repair in the moon jellyfish Aurelia aurita. Rather than regenerating lost parts, juvenile Aurelia reorganize remaining parts to regain essential body symmetry. This process that we called symmetrization is rapid and frequent, and is not driven by cell proliferation or cell death. Instead, the swimming machinery generates mechanical forces that drive symmetrization. We found evidence for symmetrization across three other species of jellyfish (Chrysaora pacifica, Mastigias sp., and Cotylorhiza tuberculata). We propose reorganization to regain function without recovery of initial morphology as a potentially broad class of self-repair strategy beyond radially symmetrical animals, and discuss the implications of this finding on the evolution of self-repair strategies in animals. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.
NASA Astrophysics Data System (ADS)
Niinemets, ÜLo; Copolovici, Lucian; Hüve, Katja
2010-12-01
Isoprene emission potential (ES) varies in tree canopies, and such variations have potentially major implications for predicting canopy level emissions. So far, quantitative relationships of ES with irradiance are missing, and interspecific variation in ES plasticity and potential effects on canopy level emissions have not been characterized. ES, foliage structural, chemical, and photosynthetic characteristics were studied relative to integrated within-canopy daily quantum flux density (Qint) in temperate deciduous tree species Quercus robur, Populus tremula, Salix alba, and Salix caprea, and canopy isoprene emissions were calculated considering observed variation in ES and under different simplifying assumptions. Strong positive curvilinear relationships between nitrogen and dry mass per unit area, photosynthetic potentials and ES per area with Qint were observed. Structural, chemical, and photosynthetic traits varied 1.5-fold to 4-fold and ES per area 3-fold to 27-fold within the canopy. ES variation reflected accumulation of mesophyll cell layers and greater emission capacity of average cells. Species with largest structural and photosynthetic plasticity had greatest plasticity in ES. Relative to the simulation considering within-canopy variation in ES, the bias from assuming a constant ES varied between -8% and +68%, and it scaled positively with ES plasticity. The bias of big-leaf simulations varied between -22% and -35%, and it scaled negatively with ES plasticity. A generalized canopy response function of ES developed for all species resulted in the lowest bias between -11% and 6% and can be recommended for practical applications. The results highlight huge within-canopy and interspecific variation in ES and demonstrate that ignoring these variations strongly biases canopy emission predictions.
Functional implications of changes in seagrass species composition in two shallow coastal lagoons
While the consequences of losing seagrass meadows are well known, there is less information on the functional implications of changes in seagrass species composition. In this study, we use data from a long-term monitoring project in shallow lagoons on the Florida Gulf Coast to as...
Signaling lymphocytic activation molecules Slam and cancers: friends or foes?
Fouquet, Gregory; Marcq, Ingrid; Debuysscher, Véronique; Bayry, Jagadeesh; Rabbind Singh, Amrathlal; Bengrine, Abderrahmane; Nguyen-Khac, Eric; Naassila, Mickael; Bouhlal, Hicham
2018-03-23
Signaling Lymphocytic Activation Molecules (SLAM) family receptors are initially described in immune cells. These receptors recruit both activating and inhibitory SH2 domain containing proteins through their Immunoreceptor Tyrosine based Switch Motifs (ITSMs). Accumulating evidence suggest that the members of this family are intimately involved in different physiological and pathophysiological events such as regulation of immune responses and entry pathways of certain viruses. Recently, other functions of SLAM, principally in the pathophysiology of neoplastic transformations have also been deciphered. These new findings may prompt SLAM to be considered as new tumor markers, diagnostic tools or potential therapeutic targets for controlling the tumor progression. In this review, we summarize the major observations describing the implications and features of SLAM in oncology and discuss the therapeutic potential attributed to these molecules.
Taymans, Jean-Marc; Nkiliza, Aurore; Chartier-Harlin, Marie-Christine
2015-08-01
Protein translation is one of the most fundamental and exquisitely controlled processes in biology, and is energetically demanding. The deregulation of this process is deleterious to cells, as demonstrated by several diseases caused by mutations in protein translation machinery. Emerging evidence now points to a role for protein translation in the pathogenesis of Parkinson's disease (PD); a debilitating neurodegenerative movement disorder. In this paper, we propose a hypothesis that protein translation machinery, PD-associated proteins and PD pathology are connected in a functional network linking cell survival to protein translation control. This hypothesis is a potential game changer in the field of the molecular pathogenesis of PD, with implications for the development of PD diagnostics and disease-modifying therapies. Copyright © 2015 Elsevier Ltd. All rights reserved.
Are sirtuins viable targets for improving healthspan and lifespan?
Baur, Joseph A.; Ungvari, Zoltan; Minor, Robin K.; Couteur, David G. Le; de Cabo, Rafael
2015-01-01
Although the increased lifespan of our populations illustrates the success of modern medicine, the risk of developing many diseases increases exponentially with old age. Caloric restriction is known to retard ageing and delay functional decline as well as the onset of disease in most organisms. Studies have implicated the sirtuins (SIRT1–SIRT7) as mediators of key effects of caloric restriction during ageing. Two unrelated molecules that have been shown to increase SIRT1 activity in some settings, resveratrol and SRT1720, are excellent protectors against metabolic stress in mammals, making SIRT1 a potentially appealing target for therapeutic interventions. This Review covers the current status and controversies surrounding the potential of sirtuins as novel pharmacological targets, with a focus on SIRT1. PMID:22653216
Innate Lymphoid Cells: A Promising New Regulator in Fibrotic Diseases.
Zhang, Yi; Tang, Jun; Tian, Zhiqiang; van Velkinburgh, Jennifer C; Song, Jianxun; Wu, Yuzhang; Ni, Bing
2016-09-02
Fibrosis is a consequence of chronic inflammation and the persistent accumulation of extracellular matrix, for which the cycle of tissue injury and repair becomes a predominant feature. Both the innate and adaptive immune systems play key roles in the progress of fibrosis. The recently identified subsets of innate lymphoid cells (ILCs), which are mainly localize to epithelial surfaces, have been characterized as regulators of chronic inflammation and tissue remodeling, representing a functional bridge between the innate and adaptive immunity. Moreover, recent research has implicated ILCs as potential contributing factors to several kinds of fibrosis diseases, such as hepatic fibrosis and pulmonary fibrosis. Here, we will summarize and discuss the key roles of ILCs and their related factors in fibrotic diseases and their potential for translation to the clinic.
Ghanekar, Yashoda; Kaur, Inderjeet
2007-01-01
In the last few years anti-vascular endothelial growth factor (VEGF) therapy has changed the paradigm in the treatment of neovascular age-related macular degeneration (ARMD). Besides, its potential use in the treatment of diabetic retinopathy and other possible proliferative vascular disorders has also shown promise. Clinical trial results have shown tremendous beneficial effect of ranibizumab in ARMD. Off-label use of bevacizumab has also shown similar benefit but long-term and clinical trial results do not exist. Some of the potential questions in the use of anti-VEGF are recurring cost, possible long-term effect on physiological function of VEGF and determination of endpoint of treatment. Overall, the use of anti-VEGF therapy in ocular angiogenesis has proven to be beneficial at least now. PMID:17951902
POTENTIAL IMPLICATIONS OF GENOMICS FOR REGULATORY AND RISK ASSESSMENT APPLICATIONS AT EPA
Benson, W.H., K. Gallagher and K. Dearfield. In press. Potential Implications of Genomics for Regulatory and Risk Assessment Applications at EPA (Abstract). To be presented at the SETAC Fourth World Congress, 14-18 November 2004, Portland, OR. 1 p. (ERL,GB R1002).
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