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Recent Findings (recent + finding)
Selected AbstractsDO RECENT FINDINGS IN PLANT MITOCHONDRIAL MOLECULAR AND POPULATION GENETICS HAVE IMPLICATIONS FOR THE STUDY OF GYNODIOECY AND CYTONUCLEAR CONFLICT?EVOLUTION, Issue 5 2008David E. McCauley The coexistence of females and hermaphrodites in plant populations, or gynodioecy, is a puzzle recognized by Darwin. Correns identified cytoplasmic inheritance of one component of sex expression, now known as cytoplasmic male sterility (CMS). Lewis established cytonuclear inheritance of gynodioecy as an example of genetic conflict. Although biologists have since developed an understanding of the mechanisms allowing the joint maintenance of CMS and nuclear male fertility restorer genes, puzzles remain concerning the inheritance of sex expression and mechanisms governing the origination of CMS. Much of the theory of gynodioecy rests on the assumption of maternal inheritance of the mitochondrial genome. Here we review recent studies of the genetics of plant mitochondria, and their implications for the evolution and transmission of CMS. New studies of intragenomic recombination provide a plausible origin for the chimeric ORFs that characterize CMS. Moreover, evidence suggests that nonmaternal inheritance of mitochondria may be more common than once believed. These findings may have consequences for the maintenance of cytonuclear polymorphism, mitochondrial recombination, generation of gynomonoecious phenotypes, and interpretation of experimental crosses. Finally we point out that CMS can alter the nature of the cytonuclear conflict that may have originally selected for uniparental inheritance. [source] The Effects of Child-Only Insurance Coverage and Family Coverage on Health Care Access and Use: Recent Findings among Low-Income Children in CaliforniaHEALTH SERVICES RESEARCH, Issue 1 2006Sylvia Guendelman Objective. To compare the extent with which child-only and family coverage (child and parent insured) ensure health care access and use for low income children in California and discuss the policy implications of extending the State Children's Health Insurance Program (California's Healthy Families) to uninsured parents of child enrollees. Data Sources/Setting. We used secondary data from the 2001 California Health Interview Survey (CHIS), a representative telephone survey. Study Design. We conducted a cross-sectional study of 5,521 public health insurance,eligible children and adolescents and their parents to examine the effects of insurance (family coverage, child-only coverage, and no coverage) on measures of health care access and utilization including emergency room visits and hospitalizations. Data Collection. We linked the CHIS adult, child, and adolescent datasets, including the adolescent insurance supplement. Findings. Among the sampled children, 13 percent were uninsured as were 22 percent of their parents. Children without insurance coverage were more likely than children with child-only coverage to lack a usual source of care and to have decreased use of health care. Children with child-only coverage fared worse than those with family coverage on almost every access indicator, but service utilization was comparable. Conclusions. While extending public benefits to parents of children eligible for Healthy Families may not improve child health care utilization beyond the gains that would be obtained by exclusively insuring the children, family coverage would likely improve access to a regular source of care and private sector providers, and reduce perceived discrimination and breaks in coverage. These advantages should be considered by states that are weighing the benefits of expanding health insurance to parents. [source] Acamprosate: Recent Findings and Future Research DirectionsALCOHOLISM, Issue 7 2008Karl Mann This article explores the mechanisms of action and the potential responder profile of acamprosate, a compound efficacious in relapse prevention of alcoholism. New evidence at the molecular and cellular level suggests that acamprosate attenuates hyper-glutamatergic states that occur during early abstinence and involves iono (NMDA)- and metabotrotropic (mGluR5) glutamate receptors along with augmented intracellular calcium release and electrophysiological changes. Thus mutant mice with enhanced glutamate levels exhibit higher alcohol consumption than wild type mice and respond better to acamprosate, demonstrating that acamprosate acts mainly on a hyper-glutamatergic system. This mode of action further suggests that acamprosate exhibits neuroprotective properties. In rats, cue-induced reinstatement behavior is significantly reduced by acamprosate treatment whereas cue-induced craving responses in alcohol-dependent patients seem not to be affected by this treatment. An ongoing study ("Project Predict") defines specific responder profiles for an individualized use of acamprosate and naltrexone. Neurophysiological as well as psychometric data are used to define 2 groups of patients: "reward cravers" and "relief cravers". While naltrexone should work better in the first group, acamprosate is hypothesized to be efficacious in the latter where withdrawal associated and/or cue induced hyper-glutamatergic states are thought to trigger relapse. Further research should target the definition of subgroups applying endophenotypic approaches, e.g. by detecting a hyperglutamatergic syndrome using MR spectroscopy. [source] Female Offspring of Alcoholic Individuals: Recent Findings on Alcoholism and Psychopathology Risks: Symposium Presented at the Research Society on Alcoholism, 2004, Vancouver Aruna Gogineni, ChairALCOHOLISM, Issue 2 2006Aruna Gogineni First page of article [source] Energy Regulation and Aging: Recent Findings and Their ImplicationsNUTRITION REVIEWS, Issue 4 2000Susan B. Roberts Ph.D. Old age is a time of vulnerability to unintentional weight loss, a factor that is associated with increased morbidity and premature death. Many possible causes of weight loss in old age have been suggested. The so-called anorexia of aging may play a particular role, by either reducing food intake directly or reducing food intake in response to such adverse factors as age-associated reductions in taste and smell, poor dentition, use of multiple prescription medicines, and depression. Recent studies also raise the question of whether a reduction in dietary variety may be important. These findings emphasize the need for regular monitoring of body weight to detect unintentional weight loss in older individuals and suggest testable ways to minimize the impact of the anorexia of aging on body weight through improved dietary management. [source] Essential roles of Gli3 and sonic hedgehog in pattern formation and developmental anomalies caused by their dysfunctionCONGENITAL ANOMALIES, Issue 3 2006Jun Motoyama ABSTRACT Pattern formation along the body axis directs the proportion of different types of cells required for functional tissue structures. The secreted protein sonic hedgehog (Shh) and zinc finger transcription factor Gli3 are key players in pattern formation during brain and limb development; the antagonistic action of Shh towards Gli3 may be crucial for pattern formation. Recent findings from Shh/Gli3 double homozygous mutants suggest that a balance of both activities is required for the production of the normal proportion of different cell types during organogenesis. This conclusion contrasts with the alternative hypothesis that a Shh gradient directs the specification of several different cell types. The observations reviewed here offer a new perspective on understanding the pathogenesis of human birth defects caused by mutations of the Shh and Gli3 genes. [source] Interactions of orexins/hypocretins with adrenocortical functionsACTA PHYSIOLOGICA, Issue 3 2010S. M. Kagerer Abstract The neuropeptides orexin A and B (hypocretin-1 and -2) are involved in numerous central regulation processes such as energy homeostasis, sleeping behaviour and addiction. The expression of orexins and orexin receptors in a variety of tissues outside the brain and the presence of orexin A in the circulation indicate the existence of an additional peripheral orexin system. Furthermore, it is well established that orexins exert an influence on the regulation of the hypothalamus,pituitary,adrenal axis, acting both on its central and peripheral branch. In rat and human adrenal cortices the expression of both orexin receptors has been verified with a predominance of OX2R. The local expression of orexin receptors was observed to be gender specific and to be modified by plasma glucose and insulin concentrations, nutritional status as well as gonadal steroids. Various studies consistently demonstrated orexin A to enhance glucocorticoid secretion of rat and human adrenal cortices, while orexin B was found to be either less potent or ineffective. On the contrary, the influence of orexins on adrenocortical aldosterone production and cell proliferation is still more controversial. Recent findings indicate that orexins stimulate adrenocortical steroidogenesis by augmenting transcription of selective steroidogenic enzymes and proteins such as steroidogenic acute regulatory protein. Both, Gq and Gs, signalling pathways with a downstream activation of MAP kinases appear to be involved in this regulation. [source] Downstream from calcium signalling: mitochondria, vacuoles and pancreatic acinar cell damageACTA PHYSIOLOGICA, Issue 1 2009S. Voronina Abstract Ca2+ is one of the most ancient and ubiquitous second messengers. Highly polarized pancreatic acinar cells serve as an important cellular model for studies of Ca2+ signalling and homeostasis. Downstream effects of Ca2+ signalling have been and continue to be an important research avenue. The primary functions regulated by Ca2+ in pancreatic acinar cells , exocytotic secretion and fluid secretion , have been defined and extensively characterized in the second part of the last century. The role of cytosolic Ca2+ in cellular pathology and the related question of the interplay between Ca2+ signalling and bioenergetics are important current research lines in our and other laboratories. Recent findings in these interwoven research areas are discussed in the current review. [source] Inhibitory functioning across ADHD subtypes: Recent findings, clinical implications, and future directionsDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 4 2008Zachary W. Adams Abstract Although growing consensus supports the role of deficient behavioral inhibition as a central feature of the combined subtype of ADHD (ADHD/C; Barkley 1997 Psychol Bull 121:65,94; Nigg 2001 Psychol Bull 127:571,598), little research has focused on how this finding generalizes to the primarily inattentive subtype (ADHD/I). This question holds particular relevance in light of recent work suggesting that ADHD/I might be better characterized as a disorder separate from ADHD/C (Diamond 2005 Dev Psychopathol 17:807,825; Milich et al. 2001 Clin Psychol Sci Pract 8:463,488). This article describes major findings in the area of inhibitory performance in ADHD and highlights recent research suggesting important areas of divergence between the subtypes. In particular, preliminary findings point to potential differences between the subtypes with respect to how children process important contextual information from the environment, such as preparatory cues that precede responses and rewarding or punishing feedback following behavior. These suggestive findings are discussed in the context of treatment implications, which could involve differential intervention approaches for each subtype targeted to the specific deficit profiles that characterize each group of children. Future research avenues aimed toward building a sound theoretical model of ADHD/I and a better understanding of its relation to ADHD/C are also presented. Specifically, investigators are encouraged to continue studying the complex interplay between inhibitory and attentional processes, as this area seems particularly promising in its ability to improve our understanding of the potentially distinct pathologies underlying the ADHD subtypes. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:268,275. [source] The role of autophagy in , -cell lipotoxicity and type 2 diabetesDIABETES OBESITY & METABOLISM, Issue 2010G. Las Autophagy, a ubiquitous catabolic pathway involved in both cell survival and cell death, has been implicated in many age-associated diseases. Recent findings have shown autophagy to be crucial for proper insulin secretion and , -cell viability. Transgenic mice lacking autophagy in their , -cells showed decreased , -cell mass and suppressed glucose-stimulated insulin secretion. Several studies showed that stress can stimulate autophagy in , -cells: the number of autophagosomes is increased in different in vivo models for diabetes, such as db/db mice, mice fed high-fat diet, pdx-1 knockout mice, as well as in in vitro models of glucotoxicity and lipotoxicity. Pharmacological and molecular inhibition of autophagy increases the susceptibility to cell stress, suggesting that autophagy protects against diabetes-relevant stresses. Recent findings, however, question these conclusions. Pancreases of diabetics and , -cells exposed to fatty acids show accumulation of abnormal autophagosome morphology and suppression of lysosomal gene expression suggesting impairment in autophagic turnover. In this review we attempt to give an overview of the data generated by others and by us in view of the possible role of autophagy in diabetes, a role which depending on the conditions, could be beneficial or detrimental in coping with stress. [source] Insulin therapy and quality of life.DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue S1 2009A review Abstract Three central goals in the treatment of diabetes mellitus are (1) the avoidance of hyperglycaemia to prevent the development or progression of diabetes complications over time, (2) the avoidance of hypoglycaemia and (3) the maintenance or achievement of good quality of life. Insulin is the most powerful agent that can be used to control blood glucose levels. This article reviews the studies that have investigated the effects of different types of insulin and insulin delivery techniques on quality of life of patients with type 1 or type 2 diabetes. First, the concept of ,quality of life' (QoL) is defined and different ways of measuring QoL are explained. Secondly, the effects of different aspects of insulin therapy on QoL are reviewed: (1) the phenomenon of ,psychological insulin resistance'; (2) the effects of different types of insulin: regular insulin versus short-acting insulin analogues, long-acting insulin analogues or biphasic mixtures; (3) multiple daily injections versus pump therapy. Having multiple complications of diabetes is clearly associated with decreased QoL. Results from large studies such as the Diabetes Control and Complications Trial (DCCT) and United Kingdom Prospective Diabetes Study (UKPDS) suggest that intensive treatment itself does not impair QoL. Recent findings further suggest that pump therapy, compared to multiple daily injections, has beneficial effects on QoL. The fact that multiple tools are used to assess QoL makes it difficult to draw conclusions regarding the effects of different types of insulin on QoL. More work on the standardization of the assessment of QoL in diabetes is urgently needed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Assessment and surgical outcomes for mild type I and severe type II cortical dysplasia: A critical review and the UCLA experienceEPILEPSIA, Issue 6 2009Jason T. Lerner Summary Recent findings on the clinical, electroencephalography (EEG), neuroimaging, and surgical outcomes are reviewed comparing patients with Palmini type I (mild) and type II (severe) cortical dysplasia. Resources include peer-reviewed studies on surgically treated patients and a subanalysis of the 2004 International League Against Epilepsy (ILAE) Survey of Pediatric Epilepsy Surgery. These sources were supplemented with data from University of California, Los Angeles (UCLA). Cortical dysplasia is the most frequent histopathologic substrate in children, and the second most common etiology in adult epilepsy surgery patients. Cortical dysplasia patients present with seizures at an earlier age than other surgically treated etiologies, and 33,50% have nonlocalized scalp EEG and normal magnetic resonance imaging (MRI) scans. 2-(18F)Fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) is positive in 75,90% of cases. After complete resection, 80% of patients are seizure free compared with 20% with incomplete resections. Compared with type I, patients with type II cortical dysplasia present at younger ages, have higher seizure frequencies, and are extratemporal. Type I dysplasia is found more often in adult patients in the temporal lobe and is often MRI negative. These findings identify characteristics of patients with mild and severe cortical dysplasia that define surgically treated epilepsy syndromes. The authors discuss future challenges to identifying and treating medically refractory epilepsy patients with cortical dysplasia. [source] In vitro interactions between sensory nerves, epidermis, hair follicles and capillaries in a tissue-engineered reconstructed skinEXPERIMENTAL DERMATOLOGY, Issue 9 2004V. Gagnon Recent findings have established that cutaneous nerves modulate both skin homeostasis and various skin diseases, by influencing cell growth and differentiation, inflammation and wound healing. In order to study the influence of epidermis, hair follicles and capillaries on sensory neurons, and vice-versa, we developed a tissue-engineered model of innervated endothelialized reconstructed skin (MIERS). Mouse dorsal root ganglia neurons were seeded on a collagen sponge populated with human fibroblasts and human endothelial cells. Keratinocytes or mice newborn immature hair follicle buds were then seeded on the opposite side of the MIERS to study their influence on sensory nerves growth, and vice versa. A vigorous neurite elongation was detected inside the reconstructed dermis after 14 and 31 days of neurons culture. The presence of endothelial cells induced a significant increase of the neurite elongation after 14 days of culture. The addition of human keratinocytes totally avoided the twofold decrease in the amount of neurites observed between 14 and 31 days in controls. We have successfully developed the MIERS that allowed us to study the effects of epidermis and capillaries on nerve growth. This model will be a useful tool to study the modulation of sensory nerves on wound healing, angiogenesis, hair growth and neurogenic inflammation in the skin. [source] Exercise-induced neuronal plasticity in central autonomic networks: role in cardiovascular controlEXPERIMENTAL PHYSIOLOGY, Issue 9 2009Lisete C. Michelini It is now well established that brain plasticity is an inherent property not only of the developing but also of the adult brain. Numerous beneficial effects of exercise, including improved memory, cognitive function and neuroprotection, have been shown to involve an important neuroplastic component. However, whether major adaptive cardiovascular adjustments during exercise, needed to ensure proper blood perfusion of peripheral tissues, also require brain neuroplasticity, is presently unknown. This review will critically evaluate current knowledge on proposed mechanisms that are likely to underlie the continuous resetting of baroreflex control of heart rate during/after exercise and following exercise training. Accumulating evidence indicates that not only somatosensory afferents (conveyed by skeletal muscle receptors, baroreceptors and/or cardiopulmonary receptors) but also projections arising from central command neurons (in particular, peptidergic hypothalamic pre-autonomic neurons) converge into the nucleus tractus solitarii (NTS) in the dorsal brainstem, to co-ordinate complex cardiovascular adaptations during dynamic exercise. This review focuses in particular on a reciprocally interconnected network between the NTS and the hypothalamic paraventricular nucleus (PVN), which is proposed to act as a pivotal anatomical and functional substrate underlying integrative feedforward and feedback cardiovascular adjustments during exercise. Recent findings supporting neuroplastic adaptive changes within the NTS,PVN reciprocal network (e.g. remodelling of afferent inputs, structural and functional neuronal plasticity and changes in neurotransmitter content) will be discussed within the context of their role as important underlying cellular mechanisms supporting the tonic activation and improved efficacy of these central pathways in response to circulatory demand at rest and during exercise, both in sedentary and in trained individuals. We hope this review will stimulate more comprehensive studies aimed at understanding cellular and molecular mechanisms within CNS neuronal networks that contribute to exercise-induced neuroplasticity and cardiovascular adjustments. [source] Natural variability of fisheries and lunar illumination: a hypothesisFISH AND FISHERIES, Issue 2 2008Santiago Hernández-León Abstract Long-term synchronous trends in small pelagic fisheries catches around the world suggest that fish populations are governed by the same global climate forcings. Recent findings regarding the population dynamics of zooplankton during the lunar cycle in sub-tropical waters may shed light on the influence of the lunar cycle on fish spawning and mortality. Here I hypothesize that, in the short-term, observed changes in zooplankton abundance during the lunar cycle promote periods of enhanced feeding by adult fish and lower mortality (and increased growth) in their early planktonic stages. Furthermore, a striking 9-year periodicity in sardine and anchovy mortality was inferred in four major upwelling areas, coinciding with the long-term variability in lunar illumination. It is suggested that both short- and long-term changes in lunar illumination should be considered when modelling the effect of climate on the natural variability of fisheries. [source] Lack of oxygen in articular cartilage: consequences for chondrocyte biologyINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 2 2010Jérôme E. Lafont Summary Controlling the chondrocytes phenotype remains a major issue for cartilage repair strategies. These cells are crucial for the biomechanical properties and cartilage integrity because they are responsible of the secretion of a specific matrix. But chondrocyte dedifferentiation is frequently observed in cartilage pathology as well as in tissue culture, making their study more difficult. Given that normal articular cartilage is hypoxic, chondrocytes have a specific and adapted response to low oxygen environment. While huge progress has been performed on deciphering intracellular hypoxia signalling the last few years, nothing was known about the particular case of the chondrocyte biology in response to hypoxia. Recent findings in this growing field showed crucial influence of the hypoxia signalling on chondrocytes physiology and raised new potential targets to repair cartilage and maintain tissue integrity. This review will thus focus on describing hypoxia-mediated chondrocyte function in the native articular cartilage. [source] Improving geriatric mental health nursing care: Making a case for going beyond psychotropic medicationsINTERNATIONAL JOURNAL OF MENTAL HEALTH NURSING, Issue 1 2003Philippe Voyer ABSTRACT Providing high-quality mental health nursing care should be an important and continuous preoccupation in the gerontological nursing field. As the proportion of elderly people in our society is growing, the emphasis on high-quality care will receive increasing attention from administrators, politicians, organized groups, researchers and clinical nurses. Recent findings illustrate unequivocally the important contribution of nurses to achieving the goal of high-quality geriatric care. However, the quality of care for the elderly with psychological difficulties has not been addressed. The objective of this article is to illustrate that while nurses can accomplish much to improve the well-being and mental health of the elderly, their skills are often underutilized. Psychotropic drugs are often the first-line interventions used by health-care professionals to treat mental health concerns of elderly persons. Alternative therapies that could be implemented and evaluated, such as psychological counselling, supportive counselling, education and life review, are infrequently used. Nevertheless, current scientific data suggest that it would be very advantageous if nurses were to play a dominant role in the care of elderly people who are depressed or experiencing sleep pattern disturbances. The same can be said about elderly chronic users of benzodiazepines, as well as those with cognitive impairment. Evidence for the use of psychotropic medications as a viable treatment option for the elderly both in the community and in the long-term care setting who are experiencing mental health challenges is examined. Alternative non-pharmacological approaches that nurses can use to augment care are also briefly discussed. [source] Medical and Functional Consequences of Anemia in the ElderlyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3s 2003David Lipschitz MD Anemia is a common problem in the elderly, accounting for significant morbidity and mortality in this population. It also has a negative effect on quality of life. Recent findings have shown that anemia can lead to cardiovascular and neurological complications, such as congestive heart failure and impaired cognitive function. In addition, anemia has been implicated in functional impairment and falls. Available data have shown that the successful management of this condition will not only improve patients' quality of life, but may also prevent the anemia from worsening. [source] Rho-GTPases: New members, new pathwaysJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2005Elena M. Sorokina Abstract Proteins comprising the Rho family of GTPases mediate reorganization of the actin cytoskeleton as well as transcription of genes. Recent findings from genome sequencing efforts, genetic screens, and signal transduction research have revealed that the Rho family contains several new, hitherto unrecognized members. In this review, we focus on these newly discovered Rho-GTPases and discuss their role in signaling to the cytoskeleton and the nucleus. © 2004 Wiley-Liss, Inc. [source] Habitat assessment for a rare, arboreal forest mammal, the tree hyrax Dendrohyrax arboreusAFRICAN JOURNAL OF ECOLOGY, Issue 2 2001A. Gaylard Abstract Recent findings have suggested that there has been a change in the structural nature of forests in the Eastern Cape, South Africa, which explains decreases in forest fauna. One of these (rare) forest species is the tree hyrax Dendrohyrax arboreus, a nocturnal, arboreal folivore, which makes use of cavity-bearing trees as dens. However, a conflict exists between the use of forest resources and in protecting habitats for the tree hyrax. In order to design appropriate management strategies, conservation authorities and forest managers require information regarding the specific habitat requirements of fauna in their forest, particularly those that are already threatened by resource use. The aims of this study were thus: (i) to characterise the den trees of D. arboreus, (ii) to determine whether D. arboreus selects for certain den tree characteristics (i.e. relative to the abundance of that characteristic); and (iii) to develop a habitat assessment model for D. arboreus. The tree hydrax was found to select for den trees with particular characteristics: seven tree species were selected as den trees, which were usually the tallest trees in the canopy (4,8 m). Den trees were usually only partly decayed, with multiple cavity entrances and trunk angles of between 45° and 68°. Cavity entrance and orientation did not appear to play a role in den tree selection by D. arboreus. A function which discriminated between den trees and non-den trees was calculated, and can be used to determine the suitability of a tree as a den for a tree hyrax (and thus to prevent it from being removed during commercial logging operations), or to assess the suitability of an area for habitation by tree hyraxes. This model can therefore help to alleviate the conflict between forest conservation managers and resource users in the Eastern Cape. Résumé Des découvertes récentes laissent entendre qu'il y a eu des changements dans la nature structurelle des forêts du Cap oriental, en Afrique du Sud, qui expliquent le déclin de la faune forestière. Une de ces (rares) espèces forestières est le daman des arbres, Dendrohyrax arboreus, un nocturne arboricole, mangeur de feuilles, qui utilise les cavités dans les arbres comme terriers. Cependant, il existe un conflit entre l'utilisation des ressources forestières et la protection de l'habitat des damans des arbres. Afin de concevoir une stratégie de gestion adéquate, les autorités de la conservation et les gestionnaires forestiers ont besoin d'informations sur les exigences spécifiques en matière d'habitat de la faune de leurs forêts et particulièrement des espèces qui sont déjà menacées par l'utilisation des ressources. Les buts de cette étude étaient donc : (i) de caractériser les arbres qui servent de refuge àD. arboreus, (ii) de déterminer si D .arboreus choisit certaines caractéristiques des arbres qui lui servent d'abris (i.e. en fonction de l'abondance de cette caractéristique) et (iii) de mettre au point un modèle d'évaluation de l'habitat pour D. arboreus. On a découvert que le daman choisissait comme refuge des arbres qui avaient certaines caractéristiques : sept espèces d'arbres étaient choisies comme abris, qui étaient d'habitude les plus hauts arbres de la canopée (4 ,,8 m). Les arbres choisis n'étaient d'habitude que partiellement abîmés, avec des nombreuses entrées vers des creux et des troncs formant un angle compris entre 45° et 68°. L'entrée et l'orientation de la cavité ne semblaient pas jouer un rôle dans le choix de l'arbre par D. arboreus. On a calculé une fonction qui faisait la distinction entre les arbres qui servaient d'abris et les autres et qui peut servir à déterminer si un arbre convient pour servir d'abri à un daman des arbres (et donc à empêcher de le supprimer lors des opérations d'abattage commercial), ou àévaluer si une zone convient comme habitat pour les damans des arbres. Ce modèle peut donc aider à réduire les conflits entre les responsables de la conservation des forêts et ceux qui veulent en utiliser les ressources au Cap oriental. [source] Familial (shared environmental and genetic) factors and the foetal origins of cardiovascular diseases and type 2 diabetes: a review of the literatureJOURNAL OF INTERNAL MEDICINE, Issue 3 2008N. Bergvall Abstract. Several researchers have argued that observed associations between birth weight and cardiovascular diseases, and type 2 diabetes, may be confounded by familial (shared environmental and genetic) factors. However, most studies have found that shared environmental factors, including socio-economic factors, do not influence the foetal origins of adult diseases. Results from two twin studies suggest that genetic factors may be of importance for the association between birth weight and risks of coronary heart disease, but findings from intergenerational studies are not consistent with genetic confounding. More studies have assessed the importance of genetic factors with respect to risk factors of coronary heart, including raised blood pressure and lipid levels. Recent findings suggest that the association between birth weight and hypertension is independent of genetic factors. In contrast, recent twin and intergenerational studies favour the hypothesis that the association between birth weight and risk of type 2 diabetes is confounded by genetic factors. [source] Understanding and altering the longitudinal course of marriageJOURNAL OF MARRIAGE AND FAMILY, Issue 4 2004Thomas N. Bradbury Weak and counterintuitive findings linking couples' interactional processes to marital outcomes have prompted new lines of research on how marriages change. Recent findings reviewed here highlight the value of (a) expanding conceptions of marital interaction by considering how social support and positive affect moderate the effects of problem-solving skills on changes in marital quality; (b) examining partners' individual strengths and vulnerabilities as antecedents of marital aggression and hostile interaction; and (c) recognizing the central role of chronic and acute circumstances in governing fluctuations in spouses' judgments of marital quality. We outline implications of these findings for ongoing efforts to prevent adverse marital outcomes, and for recent federal initiatives to strengthen healthy marriages among people with low incomes. [source] Redox-based endoplasmic reticulum dysfunction in neurological diseasesJOURNAL OF NEUROCHEMISTRY, Issue 1 2008Gábor Bánhegyi Abstract The redox homeostasis of the endoplasmic reticulum lumen is characteristically different from that of the other subcellular compartments. The concerted action of membrane transport processes and oxidoreductase enzymes maintain the oxidized state of the thiol-disulfide and the reducing state of the pyridine nucleotide redox systems, which are prerequisites for the normal functions of the organelle. The powerful thiol-oxidizing machinery allows oxidative protein folding but continuously challenges the local antioxidant defense. Alterations of the cellular redox environment either in oxidizing or reducing direction affect protein processing and may induce endoplasmic reticulum stress and unfolded protein response. The activated signaling pathways attempt to restore the balance between protein loading and processing and induce apoptosis if the attempt fails. Recent findings strongly support the involvement of this mechanism in brain ischemia, neuronal degenerative diseases and traumatic injury. The redox changes in the endoplasmic reticulum are integral parts of the pathomechanism of neurological diseases, either as causative agents, or as complications. [source] Impaired long-term depression in P2X3 deficient mice is not associated with a spatial learning deficitJOURNAL OF NEUROCHEMISTRY, Issue 5 2006Yue Wang Abstract The hippocampus is a brain region critical for learning and memory processes believed to result from long-lasting changes in the function and structure of synapses. Recent findings suggest that ATP functions as a neurotransmitter or neuromodulator in the mammalian brain, where it activates several different types of ionotropic and G protein-coupled ATP receptors that transduce calcium signals. However, the roles of specific ATP receptors in synaptic plasticity have not been established. Here we show that mice lacking the P2X3 ATP receptor (P2X3KO mice) exhibit abnormalities in hippocampal synaptic plasticity that can be restored by pharmacological modification of calcium-sensitive kinase and phosphatase activities. Calcium imaging studies revealed an attenuated calcium response to ATP in hippocampal neurons from P2X3KO mice. Basal synaptic transmission, paired-pulse facilitation and long-term potentiation are normal at synapses in hippocampal slices from P2X3KO. However, long-term depression is severely impaired at CA1, CA3 and dentate gyrus synapses. Long-term depression can be partially rescued in slices treated with a protein phosphatase 1,2 A activator or by postsynaptic inhibition of calcium/calmodulin-dependent protein kinase II. Despite the deficit in hippocampal long-term depression, P2X3KO mice performed normally in water maze tests of spatial learning, suggesting that long-term depression is not critical for this type of hippocampus-dependent learning and memory. [source] Neural differentiation and potential use of stem cells from the human umbilical cord for central nervous system transplantation therapyJOURNAL OF NEUROSCIENCE RESEARCH, Issue 8 2008Choon Bing Low Abstract The human umbilical cord is a rich source of autologous stem and progenitor cells. Interestingly, subpopulations of these, particularly mesenchymal-like cells from both cord blood and the cord stroma, exhibited a potential to be differentiated into neuron-like cells in culture. Umbilical cord blood stem cells have demonstrated efficacy in reducing lesion sizes and enhancing behavioral recovery in animal models of ischemic and traumatic central nervous system (CNS) injury. Recent findings also suggest that neurons derived from cord stroma mesenchymal cells could alleviate movement disorders in hemiparkinsonian animal models. We review here the neurogenic potential of umbilical cord stem cells and discuss possibilities of their exploitation as an alternative to human embryonic stem cells or neural stem cells for transplantation therapy of traumatic CNS injury and neurodegenerative diseases. © 2008 Wiley-Liss, Inc. [source] Identity and function of ,-secretaseJOURNAL OF NEUROSCIENCE RESEARCH, Issue 3 2003W. Taylor Kimberly Abstract ,-Secretase catalyzes intramembrane proteolysis of various type I membrane proteins, including the amyloid-, precursor protein and the Notch receptor. Despite its importance in the pathogenesis of Alzheimer's disease and to normal development, this protease has eluded identification until only very recently. Four membrane proteins are now known to be members of the protease complex: presenilin, nicastrin, aph-1, and pen-2. Recent findings suggest that these four proteins are sufficient to reconstitute the active ,-secretase complex and that together they mediate the cell surface signaling of a variety of receptors via intramembrane proteolysis. © 2003 Wiley-Liss, Inc. [source] Cell adhesion molecules for targeted drug deliveryJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 9 2006Alison L. Dunehoo Abstract Rapid advancement of the understanding of the structure and function of cell adhesion molecules (i.e., integrins, cadherins) has impacted the design and development of drugs (i.e., peptide, proteins) with the potential to treat cancer and heart and autoimmune diseases. For example, RGD peptides/peptidomimetics have been marketed as anti-thrombic agents and are being investigated for inhibiting tumor angiogenesis. Other cell adhesion peptides derived from ICAM-1 and LFA-1 sequences were found to block T-cell adhesion to vascular endothelial cells and epithelial cells; these peptides are being investigated for treating autoimmune diseases. Recent findings suggest that cell adhesion receptors such as integrins can internalize their peptide ligands into the intracellular space. Thus, many cell adhesion peptides (i.e., RGD peptide) were used to target drugs, particles, and diagnostic agents to a specific cell that has increased expression of cell adhesion receptors. This review is focused on the utilization of cell adhesion peptides and receptors in specific targeted drug delivery, diagnostics, and tissue engineering. In the future, more information on the mechanism of internalization and intracellular trafficking of cell adhesion molecules will be exploited for delivering drug molecules to a specific type of cell or for diagnosis of cancer and heart and autoimmune diseases. © 2006 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 95: 1856,1872, 2006 [source] Factors affecting the deposition of inhaled porous drug particlesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 7 2002Cynthia J. Musante Abstract Recent findings indicate that the inhalation of large manufactured porous particles may be particularly effective for drug delivery. In this study, a mathematical model was employed to systematically investigate the effects of particle size, particle density, aerosol polydispersity, and patient ventilatory parameters on deposition patterns of inhaled drugs in healthy human lungs. Aerodynamically similar particles with densities of 0.1, 1.0, and 2.0 g/cm3 were considered. Particle size distributions were defined with mass median aerodynamic diameters (MMADs) ranging from 1 to 3 ,m and geometric standard deviations ranging from 1.5 to 2.5, representing particles in the respirable size range. Breathing rates of 30 and 60 L/min with tidal volumes of 500 to 3000 mL were assumed, simulating shallow to deep breaths from a dry powder inhaler. Particles with a high density and a small geometric diameter had slightly greater deposition fractions than particles that were aerodynamically similar, but had lower density and larger geometric size (typical of manufactured porous particles). This can be explained by the fact that particles with a small geometric diameter deposit primarily by diffusion, which is a function of geometric size but is independent of density. As MMAD increased, the effect of density on deposition was less pronounced because of the decreased efficiency of diffusion for large particles. These data suggest that polydisperse aerosols containing a significant proportion of submicron particles will deposit in the pulmonary airways with greater efficiency than aerodynamically similar aerosols comprised of geometrically larger porous particles. © 2002 Wiley-Liss Inc. and the American Pharmaceutical Association J Pharm Sci 91:1590,1600, 2002 [source] Influence of standard treatment on ileal and colonic antimicrobial defensin expression in active Crohn's diseaseALIMENTARY PHARMACOLOGY & THERAPEUTICS, Issue 6 2009I. KÜBLER Summary Background, Crohn's Disease (CD), a chronic intestinal inflammation, is currently treated primarily by therapeutics which are directed against inflammatory responses. Recent findings though suggest a central role of the innate immune barrier in the pathophysiology. Important factors providing this barrier are antimicrobial peptides like the ,- and ,-defensins. Little is known about in vivo effects of common drugs on their expression. Aim, To analyse the influence of corticosteroids, azathioprine and aminosalicylate treatment on ileal and colonic antimicrobial peptides in active CD and also assess the role of inflammation. Methods, We measured the expression of antimicrobial peptides and pro-inflammatory cytokines in 75 patients with active CD. Results, Ileal and colonic ,- and ,-defensins as well as LL37 remained unaffected by corticosteroids, azathioprine or aminosalicylate treatment. Additionally, we did not observe a negative coherency between Paneth cell ,-defensins and any measured cytokines. HBD2 and LL37 unlike HBD1 levels were linked to inflammatory cytokines and increased in highly inflamed samples. Conclusions, Current oral drug treatment seems to have no major effect on the expression of antimicrobial peptides. In contrast to HBD2 and LL37, ileal levels of HD5 and HD6 and colonic HBD1 level are independent of current inflammation. Innovative drugs should aim to strengthen protective innate immunity. [source] Antioxidant and other biological activities of phenols from olives and olive oilMEDICINAL RESEARCH REVIEWS, Issue 1 2002Francesco Visioli Abstract Olive oil is the principal source of fats in the Mediterranean diet, which has been associated with a lower incidence of coronary heart disease and certain cancers. Phenolic compounds, e.g., hydroxytyrosol and oleuropein, in extra-virgin olive oil are responsible for its peculiar pungent taste and for its high stability. Recent findings demonstrate that olive oil phenolics are powerful antioxidants, both in vitro and in vivo, and possess other potent biological activities that could partially account for the observed healthful effects of the Mediterranean diet. © 2001 John Wiley & Sons, Inc. Med Res Rev, 22, No. 1, 65,75, 2002 [source] | |||||||||||||||||||||||||||||||||||||||||||||||||