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Long-term Consequences (long-term + consequence)
Selected AbstractsPRISON GANG POLICY AND RECIDIVISM: SHORT-TERM MANAGEMENT BENEFITS, LONG-TERM CONSEQUENCESCRIMINOLOGY AND PUBLIC POLICY, Issue 2 2007MARIE GRIFFIN First page of article [source] Early Low-Grade Proteinuria: Causes, Short-Term Evolution and Long-Term Consequences in Renal TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 9 2005Jean-Michel Halimi Proteinuria 1 year after transplantation is associated with poor renal outcome. It is unclear whether low-grade (<1 g/24 h) proteinuria earlier after transplantation and its short-term change affect long-term graft survival. The effects of proteinuria and its change on long-term graft survival were retrospectively assessed in 484 renal transplant recipients. One- and 3-month proteinuria correlated with donor age, donor cardiovascular death, prolonged cold and warm ischemia times and acute rejection. One- and 3-month proteinuria (per 0.1 g/24 h, hazard ratio (HR): 1.07 and 1.15, p < 0.0001),especially low-grade proteinuria (HR: 1.20 and 1.26, p < 0.0001),were powerful, independent predictors of graft loss. Its short-term reduction correlated with arterial pressure (AP) (the lower the 3-month diastolic and 12-month systolic AP, the lower the risk of increasing proteinuria during 1,3 months and 3,12 months periods, respectively: Odds ratio (OR) per 10 MmHg: 0.78, p = 0.01 and 0.85, respectively, p = 0.02), and was associated with decreased long-term graft loss (per 0.1 g/24 h: HR: 0.88 and 0.98, respectively, p < 0.0001), independently of initial proteinuria. Early low-grade proteinuria due to pre-transplant renal lesions, ischemia-reperfusion and immunologic injuries is a potent predictor of graft loss. Short-term reduction in proteinuria is associated with improved long-term graft survival. [source] Echocardiographic changes and risk factors for left ventricular hypertrophy in children and adolescents after renal transplantationPEDIATRIC TRANSPLANTATION, Issue 3 2004Amr A. El-Husseini Abstract:, Long-term consequences of cardiac alteration in children with chronic renal failure and after renal transplantation are largely unknown. In chronic uremia, cardiomyopathy manifests itself as systolic dysfunction, concentric left ventricular hypertrophy (LVH) or left ventricular dilatation. The correction of uremic state by renal transplantation leads to normalization of left ventricular contractility, regression of LVH and improvement of cavity volume and so dialysis patients with uremic cardiomyopathy would benefit from renal transplantation. We studied 73 patients, aged 17 yr or less, who underwent renal transplantation in our center. This cross-sectional study was performed 4.6 yr (median) after transplantation. Of the total, 48 were males and 25 were females. Transthoracic echocardiographic examination was performed for all cases. The effects of clinical, demographic, biochemical and therapeutic data on echocardiographic parameters were assessed. Multivariate analysis was used to assess the relation between the risk factors and the left ventricular muscle mass index. The most common echocardiographic abnormalities were the LVH (47.9%), left atrial enlargement (31.5%) and left ventricular dilatation and systolic dysfunction (13.7% for each). The pretransplant dialysis, arteriovenous fistula, acute rejection, cumulative steroid dose per square meter surface area, post-transplant hypertension, anemia and graft dysfunction were significant risk factors for LVH by univariate analysis. The significant factors by multivariate analysis were pretransplant dialysis, post-transplant hypertension and anemia. From this study we may conclude that LVH is a common problem among renal transplant children and adolescents. Early transplantation, control of hypertension and correction of anemia may be beneficial regarding left ventricular function and structure. [source] The impact of childhood cancer on the family: a qualitative analysis of strains, resources, and coping behaviorsPSYCHO-ONCOLOGY, Issue 6 2004Joän M. Patterson Clinical research has led to tremendous improvements in treatment efficacy for most childhood cancers; overall 5-year survival is now greater than 75%. Long-term consequences of cure (i.e. adverse medical and psychosocial effects) have only recently begun to emerge as a primary focus of clinical research, including studies of health-related quality of life among survivors. Usually lacking in such efforts, however, is consideration of the impact of the cancer experience on the family, and the influence that the family's response to cancer has on quality of life in the child. From this qualitative analysis of seven focus groups with 45 parents of children a year or more out of cancer treatment, we report those aspects of a child's cancer diagnosis, treatment, and recovery that parents perceived as particularly difficult for their family, and the resources and coping behaviors parents perceived as helpful to their family in dealing with and managing the cancer experience. Using the Family Adjustment and Adaptation Response theoretical model to organize the data, the domains of strains and resources were delineated into themes and sub-themes related to the cancer, child, family, health-care system, and community. Within a third domain, coping, sub-themes were identified within the themes of appraisal-focused, problem-focused, and emotion-focused coping behaviors. Integration of this information should serve to improve future studies of health-related quality of life among children who survive cancer. Copyright © 2003 John Wiley & Sons, Ltd. [source] Glomerular Size in Early Protocol Biopsies is Associated with Graft OutcomeAMERICAN JOURNAL OF TRANSPLANTATION, Issue 12 2005F. Azevedo Long-term consequences of glomerular enlargement after transplantation are not well understood. The aim is to evaluate the relationship between glomerular volume (Vg) estimated in protocol biopsies, graft function and graft survival. Vg and Banff chronic damage score were evaluated in protocol biopsies at 4 months. Creatinine clearance (CrCl) was estimated by the Cockroft-Gault formula. Vg estimated in 144 patients was 4.8 ± 2.0 × 106,3. It was associated with donor age (r = 0.23, p < 0.01), recipient body mass index (r = 0.17, p = 0.04), delayed graft function (Vg = 5.9 ± 2.3 vs. 4.6 ± 1.9 × 106,3, p < 0.01) and CrCl (r = 0.17, p = 0.04). The best cutoff of Vg, Banff chronic damage score and CrCl was determined by Cox regression analysis, being 5.0 × 106,3 for Vg (relative risk (RR): 2.4, 95% confidence interval (CI): 1.03,5.6), >2 for chronic damage score (RR: 3.4, 95% CI: 1.03,8.9) and 60 mL/min for CrCl (RR: 3.5, 95% CI: 1.04,11.9). These variables were independent predictors of death-censored graft survival. According to Vg and CrCl, four groups of patients were defined. Patients with small glomeruli and high CrCl had a 95% graft survival while patients with large glomeruli and low CrCl had a 45% graft survival at 15 years (p < 0.01). Large glomerular volume, high Banff chronic score and poor early renal function in stable grafts are independently associated with death-censored graft survival. [source] Long-term survey of laryngoplasty and ventriculocordectomy in an older, mixed-breed population of 200 horses.EQUINE VETERINARY JOURNAL, Issue 4 2003Part 1: Maintenance of surgical arytenoid abduction, complications of surgery Summary Reasons for performing study: Laryngoplasty (LP) is currently the most common surgical treatment for equine laryngeal paralysis, however, there have been no reports quantifying the degree of retention of arytenoid abduction following L P. ADitionally, the complications of LP have been poorly documented. Objectives: To record the degree of arytenoid abduction retention following LP and to accurately document all complications of surgery. Methods: A study (1986,1998) of 200 horses of mixed breed and workload, median age 6 years (prospective 136 cases and retrospective 64 cases) undergoing LP (using 2 stainless steel wires) and combined ventriculocordectomy was undertaken; 198 owners completed questionnaires, a median of 19 months following surgery. The degree of arytenoid abduction achieved was endoscopically, semi-quantitatively evaluated using a 5-grade system, at 1 day, 7 days, and 6 weeks after surgery. Results: On the day following LP, 62% of horses had good (median grade 2) arytenoid abduction, 10% had excessive (grade 1), and 5% had minimal (grade 4) abduction (overall - median grade 2). Due to progressive loss of abduction, moderate (median grade 3, range 1,5) abduction was present overall at 1 and 6 weeks after LP. Further surgery was required to re-tighten prostheses in 10% of cases with excessive loss of abduction, or to loosen prostheses in 7% of horses which had continuing high levels of LP abduction and significant post operative dysphagia. LP wound problems (mainly seromas and suture abscesses) were reported to last <2 weeks in 9% of cases, <4 weeks in 4% and >4 weeks in 4%. The (partially sutured) laryngotomy wounds discharged post operatively for <2 weeks in 22% of cases, <4 weeks in 7% and for >4 weeks in 2%. Coughing occurred at some stage post operatively in 43% of cases and its presence correlated significantly with the degree of surgical arytenoid abduction. This coughing occurred during eating in 24% of cases and was not associated with eating (or dysphagia) in the other 19% of cases. Chronic (>6 months duration) coughing occurred in 14% of cases, but appeared to be due to intercurrent pulmonary disease in half of these horses. Conclusions: Suturing the cricotracheal membrane allows most laryngotomy wounds to heal quickly. Laryngoplasty wound problems were of little long-term consequence when stainless steel wire prostheses were used. Potential relevance: A significant loss of LP abduction occurs in most horses in the 6 weeks following surgery and efforts should be made to find ways to prevent such loss. However, excessive LP abduction is associated with post operative dysphagia and coughing. [source] Open Borders: Absurd Chimera or Inevitable Future Policy?INTERNATIONAL MIGRATION, Issue 5 2010John P. Casey In the current climate of security concerns, the movement of people across borders is becoming increasingly criminalised. Yet there is a parallel political and economic reality in which borders are opening and the movement of people is being liberalised: zones of free movement such as the European Union expand; other bilateral and multilateral agreements include provisions for more fluid cross-border movement; international trade negotiations seek to facilitate the flow of those providing goods and services; developing countries' push for greater access for their citizens to the labour markets of the industrialised world; and a new class of "gold collar" professionals moves with increasing ease around the globe. This paper explores the possibilities of universal open borders as a future policy option. The author accepts realpolitik and understands that the free flow of immigrants is currently impossible, but also maintains that open borders are an inevitable long-term consequence of globalisation, as well as a policy option for addressing North-South inequalities and a moral touchstone for the global extension of human rights. The paper does not advocate for more migration, but instead explores the paradox that the creation of the conditions that would allow for the opening of borders is likely to reduce the incentives for emigration. The paper explores the policy changes needed to achieve open borders. [source] Ongoing activation of p53 pathway responses is a long-term consequence of radiation exposure in vivo and associates with altered macrophage activities,THE JOURNAL OF PATHOLOGY, Issue 5 2008PJ Coates Abstract The major adverse consequences of radiation exposure, including the initiation of leukaemia and other malignancies, are generally attributed to effects in the cell nucleus at the time of irradiation. However, genomic damage as a longer term consequence of radiation exposure has more recently been demonstrated due to untargeted radiation effects including delayed chromosomal instability and bystander effects. These processes, mainly studied in vitro, are characterized by un-irradiated cells demonstrating effects as though they themselves had been irradiated and have been associated with altered oxidative processes. To investigate the potential for these untargeted effects of radiation to produce delayed damaging events in vivo, we studied a well-characterized model of radiation-induced acute myeloid leukaemia in CBA/Ca mice. Haemopoietic tissues of irradiated CBA/Ca mice exhibit enhanced levels of p53 stabilization, increased levels of p21waf1, and increased amounts of apoptosis, as expected, in the first few hours post-irradiation, but also at much later times: weeks and months after the initial exposure. Because these responses are seen in cells that were not themselves directly irradiated but are the descendants of irradiated cells, the data are consistent with an initial radiation exposure leading to persistently increased levels of ongoing DNA damage, analogous to radiation-induced chromosomal instability. To investigate the potential source of ongoing oxidative processes, we show increased levels of 3-nitrotyrosine, a marker of damaging nitrogen/oxygen species in macrophages. Not all animals show increased oxidative activity or p53 responses as long-term consequences of irradiation, but increased levels of p53, p21, and apoptosis are directly correlated with increased 3-nitrotyrosine in individual mice post-irradiation. The data implicate persistent activation of inflammatory-type responses in irradiated tissues as a contributory bystander mechanism for causing delayed DNA damage. Copyright © 2008 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Developmental toxicity of estrogenic chemicals on rodents and other speciesCONGENITAL ANOMALIES, Issue 2 2002Taisen Iguchi ABSTRACT, Antenatal sex-hormone exposure induces lesions in mouse reproductive organs, which are similar to those in humans exposed in utero to a synthetic estrogen, diethylstilbestrol. The developing organisms including rodents, fish and amphibians are particularly sensitive to exposure to estrogenic chemicals during a critical window. Exposure to estrogens during the critical period induces long-term changes in reproductive as well as non-reproductive organs, including persistent molecular alterations. The antenatal mouse model can be utilized as an indicator of possible long-term consequences of exposure to exogenous estrogenic compounds including possible environmental endocrine disrupters. Many chemicals released into the environment potentially disrupt the endocrine system in wildlife and humans, some of which exhibit estrogenic activity by binding to the estrogen receptors. Estrogen responsive genes, therefore, need to be identified to understand the molecular basis of estrogenic actions. In order to understand molecular mechanisms of estrogenic chemicals on developing organisms, we are identifying estrogen responsive genes using cDNA microarray, quantitative RT-PCR, and differential display methods, and genes related to the estrogen-independent vaginal changes in mice induced by estrogens during the critical window. In this review, discussion of our own findings related to endocrine distuptor issue will be provided. [source] SELF-CONTROL, CRIMINAL MOTIVATION AND DETERRENCE: AN INVESTIGATION USING RUSSIAN RESPONDENTSCRIMINOLOGY, Issue 2 2005CHARLES R. TITTLE With data from respondents in Nizhni Novgorod, Russia, we address the generality of self-control theory. We also assess two hypotheses. The first focuses on the attractiveness of criminal acts, that is, motivation toward crime. The second concerns the contention that the mediating link between self-control and criminal conduct is the failure of those with less self-control to anticipate the long-term costs of misbehavior. Although the magnitude of associations between self-control and indicators of criminal behavior is about the same in this study as it is in others, which suggests that the theory is not culturally bound, those associations are largely overshadowed by criminal attraction. Consistent with that, failure to anticipate costly long-term consequences does not appear to be the mediating link between self-control and criminal behavior: the evidence shows no tendency for sanction fear to be greater among those with greater self-control. In fact, sanction fear is modestly and significantly related to the crime measures independent of self-control, though sanction fear also appears to be influenced by criminal attraction. The results suggest that in the production of criminal behavior, motivation may be more important than controls inhibiting criminal impulses. [source] Reducing Child Poverty with Cash Transfers: A Sure Thing?DEVELOPMENT POLICY REVIEW, Issue 5 2006Armando Barrientos Children are disproportionately represented among the income-poor, many suffer from severe deprivation, and their poverty and vulnerability have cumulative and long-term consequences. This article provides a comparative examination of the poverty-reduction effectiveness of cash transfer programmes targeting children, focusing on three types of such programmes: the Child Support Grant in South Africa, family allowances in transition countries, and targeted conditional cash transfer programmes in Latin America and the Caribbean. It finds that, despite differences in design, cash transfer programmes targeting children in poor households are an effective way of reducing poverty. [source] Olfactory association learning and brain-derived neurotrophic factor in an animal model of early deprivationDEVELOPMENTAL PSYCHOBIOLOGY, Issue 4 2009Betty Zimmerberg Abstract Animal models can serve to explore neural mechanisms underlying the effects of stressful early experiences on behaviors supporting attachment. Neonatal rats primarily use olfaction for attachment, and Brain-Derived Neurotrophic Factor (BDNF) may be a key transcription target in olfactory association learning. In this experiment, neonatal male and female rats were isolated individually for 3 hr daily in the first week of life while their dams were left with partial litters (Early Deprivation, ED) or remained undisturbed (Control). At 1 week of age, subjects were tested using a 2-day classical conditioning paradigm. The conditioned group (O/M) was exposed to a novel odor paired with a milk infusion. Three additional groups included an unpaired odor and milk exposure group (O/M unP), an odor exposure alone group (O/NM), and neither an odor nor a milk group (NO/NM). Learning the odor association, as revealed in a position preference for the novel odor, was accompanied by an increase in hippocampal BDNF in O/M subjects from undisturbed Control litters. BDNF levels were also positively related to degree of preference for the odor in the O/M Control group. ED subjects did not make the classically conditioned odor association and did not show an increase in hippocampal BDNF. ED increased BDNF levels in the olfactory bulb compared to Controls regardless of training group; individual levels were not correlated with performance because samples were pooled. These results suggest that changes in the transcription of BDNF may underlie some of the long-term consequences of the early stress of maternal separation. © 2009 Wiley Periodicals, Inc. Dev Psychobiol 51: 333,344, 2009. [source] The effect of prenatal hypoxia on brain development: short- and long-term consequences demonstrated in rodent modelsDEVELOPMENTAL SCIENCE, Issue 4 2006Hava Golan Hypoxia (H) and hypoxia-ischemia (HI) are major causes of foetal brain damage with long-lasting behavioral implications. The effect of hypoxia has been widely studied in human and a variety of animal models. In the present review, we summarize the latest studies testing the behavioral outcomes following prenatal hypoxia/hypoxia-ischemia in rodent models. Delayed development of sensory and motor reflexes during the first postnatal month of rodent life was observed by various groups. Impairment of motor function, learning and memory was evident in the adult animals. Activation of the signaling leading to cell death was detected as early as three hours following H/HI. An increase in the counts of apoptotic cells appeared approximately three days after the insult and peaked about seven days later. Around 14,20 days following the H/HI, the amount of cell death observed in the tissue returned to its basal levels and cell loss was apparent in the brain tissue. The study of the molecular mechanism leading to brain damage in animal models following prenatal hypoxia adds valuable insight to our knowledge of the central events that account for the morphological and functional outcomes. This understanding provides the starting point for the development and improvement of efficient treatment and intervention strategies. [source] Islet transplantation: where do we stand now?,DIABETES/METABOLISM: RESEARCH AND REVIEWS, Issue 3 2003Boaz Hirshberg Abstract After many years of limited success in islet transplantation, researchers developing this procedure have made great strides, and several centers have now reported that islet transplantation can result in long-term insulin independence for patients with type 1 diabetes mellitus. The improved quality of life achieved in some islet allograft recipients suggests that this important line of investigation should proceed. Yet, several factors limit the technique and these hurdles must be overcome before it can be considered a practical treatment for the millions of individuals with diabetes, be it type 1 or type 2. Most obvious is the gross disparity between the number of islets available for clinical transplantation and the number of patients with diabetes who might benefit. Other important limitations, too often lost in the discussion, include complications associated with the technique itself, the toxicity of currently available immunosuppressive drugs, and the imperfect glycemia control achieved in most patients. In fact, our ongoing analysis as to whether transplantation-based therapy improves survival for patients with type 1 diabetes suggests that, for many at least, the opposite may be true. Two variables, as yet undefined, also need to be considered: (1) can the procedure, when done well, prevent or reverse diabetes-associated complications and (2) what are the long-term consequences of intrahepatic islets? Published in 2003 by John Wiley & Sons, Ltd. [source] Health Status among Emergency Department Patients Approximately One Year after Consecutive Disasters in New York CityACADEMIC EMERGENCY MEDICINE, Issue 10 2005William George Fernandez MD Abstract Objectives: Emergency department (ED) patients with disaster-related experiences may present with vague symptoms not clearly linked to the event. In 2001, two disasters in New York City, the World Trade Center disaster (WTCD) and the subsequent American Airlines Flight 587 crash, presented an opportunity to study long-term consequences of cumulative disaster exposure (CDE) on health-related quality of life (HRQOL) among ED patients. Methods: From July 15 to October 30, 2002, a systematic sample of stable, adult patients from two EDs in New York City were enrolled. Participants completed a self-administered questionnaire. The Short Form 36 (SF-36) was used to assess overall health status. Bivariate analyses were conducted to identify individual correlates of worsening health status. Multivariate regression was performed to identify the association between various factors and overall health status, while controlling for relevant sociodemographic variables. Results: Four hundred seventy-one patients (54.6% female) participated. The participation rate was 73.4%. One hundred sixty-one participants (36%) reported direct, indirect, or occupational exposure to the WTCD; 55 (13.3%) had direct, indirect, or occupational exposure to the plane crash; 33 (8.1%) had both exposures. In separate multivariate models, CDE predicted lower SF-36 scores for general health (p < 0.0096), mental health (p < 0.0033), and bodily pain (p < 0.0046). Conclusions: In the year following mass traumatic events, persons with CDE had lower overall health status than those with one or no disaster exposure. Clinicians should consider the impact that traumatic events have on the overall health status of ED patients in the wake of consecutive disasters. [source] PRECLINICAL STUDY: Amphetamine- and nicotine-induced cross-sensitization in adolescent rats persists until adulthoodADDICTION BIOLOGY, Issue 3 2009Gabriela C. Santos ABSTRACT Nicotine and psychostimulants are often abused in combination and drug abuse often begins during adolescence and can have long-term consequences. Behavioral sensitization has been suggested as an animal model of neuroplasticity implicated in the development of drug addiction. We evaluated whether the pretreatment with nicotine (0.4 mg/kg; s.c.) or amphetamine (5.0 mg/kg; i.p.) in adolescent rats [from postnatal day (P) 28 to P34] could induce cross-sensitization to nicotine and amphetamine when animals were challenged during both adolescence (P37) and adulthood (P70), in separate groups of animals. Adolescent animals pretreated with amphetamine displayed behavioral sensitization to nicotine, which persisted until adulthood. Moreover, adolescent animals pretreated with nicotine showed sensitized locomotor response to amphetamine in the adulthood. These data suggest that adolescents who abuse nicotine may be particularly susceptible to the effects of amphetamine and vice versa. Moreover, this increased vulnerability may persist through their development until adulthood. [source] Requirement of cannabinoid CB1 receptors in cortical pyramidal neurons for appropriate development of corticothalamic and thalamocortical projectionsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2010Chia-Shan Wu Abstract A role for endocannabinoid signaling in neuronal morphogenesis as the brain develops has recently been suggested. Here we used the developing somatosensory circuit as a model system to examine the role of endocannabinoid signaling in neural circuit formation. We first show that a deficiency in cannabinoid receptor type 1 (CB1R), but not G-protein-coupled receptor 55 (GPR55), leads to aberrant fasciculation and pathfinding in both corticothalamic and thalamocortical axons despite normal target recognition. Next, we localized CB1R expression to developing corticothalamic projections and found little if any expression in thalamocortical axons, using a newly established reporter mouse expressing GFP in thalamocortical projections. A similar thalamocortical projection phenotype was observed following removal of CB1R from cortical principal neurons, clearly demonstrating that CB1R in corticothalamic axons was required to instruct their complimentary connections, thalamocortical axons. When reciprocal thalamic and cortical connections meet, CB1R-containing corticothalamic axons are intimately associated with elongating thalamocortical projections containing DGL,, a 2-arachidonoyl glycerol (2-AG) synthesizing enzyme. Thus, 2-AG produced in thalamocortical axons and acting at CB1Rs on corticothalamic axons is likely to modulate axonal patterning. The presence of monoglyceride lipase, a 2-AG degrading enzyme, in both thalamocortical and corticothalamic tracts probably serves to restrict 2-AG availability. In summary, our study provides strong evidence that endocannabinoids are a modulator for the proposed ,handshake' interactions between corticothalamic and thalamocortical axons, especially for fasciculation. These findings are important in understanding the long-term consequences of alterations in CB1R activity during development, a potential etiology for the mental health disorders linked to prenatal cannabis use. [source] Glutamate regulates retinal progenitors cells proliferation during developmentEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2006Rodrigo A. P. Martins Abstract The precise coordination of cell cycle exit and cell fate specification is essential for generating the correct proportion of retinal cell types during development. The decision to exit the cell cycle is regulated by intrinsic and extrinsic cues. There is growing evidence that neurotransmitters can regulate cell proliferation and cell fate specification during the early stages of CNS development prior to the formation of synaptic connections. We found that the excitatory neurotransmitter glutamate regulates retinal progenitor cell proliferation during embryonic development of the mouse. AMPA/kainate and N -methyl- d -aspartate receptors are expressed in embryonic retinal progenitor cells. Addition of exogenous glutamate leads to a dose-dependent decrease in cell proliferation without inducing cell death or activating the p53 pathway. Activation of AMPA/kainate receptors induced retinal progenitor cells to prematurely exit the cell cycle. Using a replication-incompetent retrovirus to follow the clonal expansion of individual retinal progenitor cells, it was observed that blockade of AMPA/kainate receptors increased the proportion of large clones, showing that modulation of endogenous glutamatergic activity can have long-term consequences on retinal cell proliferation. Real time reverse transcriptase-polymerase chain reaction and immunoblot analyses demonstrated that glutamate does not alter the levels of the mRNA and proteins that regulate the G1/S-phase transition. Instead, the activity of the Cdk2 kinase is reduced in the presence of glutamate. These data indicate that glutamate regulates retinal progenitor cell proliferation by post-translational modulation of cyclin/Cdk2 kinase activity. [source] New genomic avenues in behavioural neuroendocrinology ,EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2002S. L. Lightman Abstract Neuroendocrine systems play a key role not only in the maintenance of whole-body homeostasis but also as the link between behavioural, endocrine and autonomic responses to environmental stimuli. It is becoming increasingly clear that neuroendocrine regulatory mechanisms are under the control of a combination of factors including genetic background, environment and early-life programming. Patterns of gene expression are increasingly being used to provide information on the genotypes associated with particular behaviours, and modulation of specific parts of the genome allow investigation of the contribution of particular genes. The sequencing of the genome provides a unique opportunity to elucidate the genetic contribution to neuroendocrine and behavioural processes, and to investigate the interactions between genetic and environmental factors. Although drugs can be used to activate or inhibit neurotransmitters and receptors, they lack specificity. New technologies now permit the activation or inactivation of both neurotransmitters and receptors in specific areas of the brain for defined periods, including crucially important developmental windows when activation appears to have long-term consequences. The future challenges are to define the critical mechanisms through which the genetic constitution of an individual human or experimental animal interacts with environmental cues to result in altered physiological or even pathological behaviour and endocrine function. [source] BIOTIC INTERACTIONS AND MACROEVOLUTION: EXTENSIONS AND MISMATCHES ACROSS SCALES AND LEVELSEVOLUTION, Issue 4 2008David Jablonski Clade dynamics in the fossil record broadly fit expectations from the operation of competition, predation, and mutualism, but data from both modern and ancient systems suggest mismatches across scales and levels. Indirect effects, as when antagonistic or mutualistic interactions restrict geographic range and thereby elevate extinction risk, are probably widespread and may flow in both directions, as when species- or organismic-level factors increase extinction risk or speciation probabilities. Apparent contradictions across scales and levels have been neglected, including (1) the individualistic geographic shifts of species on centennial and millennial timescales versus evidence for fine-tuned coevolutionary relationships; (2) the extensive and dynamic networks of interactions faced by most species versus the evolution of costly enemy-specific defenses and finely attuned mutualisms; and (3) the macroevolutionary lags often seen between the origin and the diversification of a clade or an evolutionary novelty versus the rapid microevolution of advantageous phenotypes and the invasibility of most communities. Resolution of these and other cross-level tensions presumably hinges on how organismic interactions impinge on genetic population structures, geographic ranges, and the persistence of incipient species, but generalizations are not yet possible. Paleontological and neontological data are both incomplete and so the most powerful response to these problems will require novel integrative approaches. Promising research areas include more realistic approaches to modeling and empirical analysis of large-scale diversity dynamics of ostensibly competing clades; spatial and phylogenetic dissections of clades involved in escalatory dynamics (where prey respond evolutionarily to a broad and shifting array of enemies); analyses of the short- versus long-term consequences of mutualistic symbioses; and fuller use of abundant natural experiments on the evolutionary impacts of ecosystem engineers. [source] Keeping up or Falling behind?FISCAL STUDIES, Issue 4 2008Poverty, Tax Uprating on Incomes, The Impact of Benefit D31; I38 Abstract Each year, the government decides how much to raise benefits and tax allowances. In the UK, the basis for these upratings is rarely debated, yet has major long-term consequences for the relative living standards of different groups as well as for the public finances. This paper considers the medium-term implications of present uprating policies, which vary across parameters of the tax,benefit system. Continuing these policies for 20 years, other things staying the same, would result in a near doubling of the child poverty rate alongside a substantial gain to the public finances. At the same time, pensioners are largely protected by the earnings indexation of pensioner benefits including, in time, the basic state pension. We show how difficult it will be to meet the UK child poverty targets unless the greater inequality inherent in the current regime for uprating payments and allowances is redressed. [source] Climate change and bet-hedging: interactions between increased soil temperatures and seed bank persistenceGLOBAL CHANGE BIOLOGY, Issue 10 2009MARK K. J. OOI Abstract In order to predict the long-term consequences of climate change, it is necessary to link future environmental changes to mechanisms that control plant population processes. This information can then be incorporated into strategies to more accurately model climate change impacts on species or to estimate future extinction risks. We examined the impact of increased temperatures on the longevity and dynamics of the persistent soil seed banks of eight ephemeral species from arid Australia. We found that the predicted global temperature increases under climate change will be reflected in increased soil temperatures, and that seeds in the soil seed bank will be exposed to long durations of high temperatures over the summer months. Three of the eight species studied had significantly greater levels of germination after exposure to predicted increased soil temperatures. Another species displayed a dramatic decrease in seed viability after such exposure. The capacity of such species to use the seed bank to bet hedge against rainfall events that cause germination but are insufficient to allow plant maturation, is compromised by increased germinability and subsequent loss or reduction of seed bank persistence. These predicted changes in the dynamics of soil seed banks increase the risk of local extinctions of these species, while the composition of the community may be altered by changes in species abundance. Our results show that the risk spreading mechanism provided by persistent seed banks could be compromised by the mechanistic impact of forecast temperature increases in arid habitats, and highlight the need to understand mechanisms that control population dynamics when attempting to address likely future impacts of climate change on biodiversity. [source] Poor nutritional condition as a consequence of high dominance status in the Coal Tit Parus aterIBIS, Issue 1 2004Jacqueline M. Hay The costs and benefits of dominance status have been investigated in the past and it has generally been reported that subdominant birds are at a nutritional disadvantage owing to their low dominance status. The nutritional condition of birds during winter can be important in determining their likelihood of survival. This is particularly so in small passerines that are sensitive to severe weather conditions. Ptilochronology is an accurate method used to produce a long-term estimate of body condition spanning the number of days that it takes to grow a new feather. Ptilochronology was used during this study to estimate the nutritional condition of Coal Tits Parus ater during one winter and how condition was affected by dominance status. Dominant Coal Tits produced poorer quality feathers, which they grew at a slower rate, than did subdominant conspecifics. This study highlights a nutritional cost to high dominance status that could have long-term consequences because the induced tail feathers will not be replaced for at least 5 months. [source] Lymphoma risk in inflammatory bowel disease: Is it the disease or its treatment?INFLAMMATORY BOWEL DISEASES, Issue 10 2007Jennifer L. Jones MD Abstract With the increasingly widespread use of immunosuppressive and biologic agents for the treatment of Crohn's disease and ulcerative colitis come concerns about potential long-term consequences of such therapies. Disentangling the potential confounding effects of the underlying disease, its extent, severity, duration, and behavior, and concomitant medical therapy has proven to be exceedingly difficult. Unlike the case in rheumatoid arthritis, the overwhelming preponderance of population-based evidence suggests that a diagnosis of inflammatory bowel disease (IBD) is not associated with an increased relative risk of lymphoma. However, well-designed studies that evaluate the potential modifying effect of IBD severity have yet to be performed. Although the results from hospital- and population-based studies have conflicted, the results of a recent meta-analysis suggest that patients receiving purine analogs for the treatment of IBD have a lymphoma risk ,4-fold higher than expected. Analyses of lymphoma risk in patients receiving biologic agents directed against tumor necrosis factor-alpha are confounded by concomitant use of immunosuppressive agents in most of these patients. Nevertheless, there may be a small but real risk of lymphoma associated with these therapies. Although the relative risk of lymphoma may be elevated in association with some of the medical therapies used in the treatment of IBD, this absolute risk is low. Weighing the potential risk of lymphoma associated with select medical therapies against the risk of undertreating IBD will help physicians and patients to make more informed decisions pertaining to the medical management of IBD. (Inflamm Bowel Dis 2007) [source] Earlier stress exposure and subsequent major depression in aging womenINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 1 2010Stephanie Kasen Abstract Objective Despite evidence that stress exposure earlier in the life course may have long-term consequences for psychopathology, most models of vulnerability for late life depression are limited to current stressors or to retrospective reports of stress history. This study estimates the influences of earlier stressors assessed longitudinally on subsequent major depressive disorder (MDD) in women at average age 60 (range 50,75). Method MDD, negative life events (NLE), and marital stress were assessed multiple times in a community-based sample of 565 women followed for three decades. Adverse events experienced in childhood also were assessed prior to outcome. Results Greater childhood adversity, earlier high levels of NLE and marital stress, and a more rapid increase in marital stress over time elevated the odds of MDD at average age 60 independent of all stressors and other salient risk factors. Childhood adversity was mediated in part by intervening risks. Prior depression, earlier poor health status, a more rapid deterioration in health with age, and current disability owing to physical problems also were related independently to later MDD. Conclusions These findings support the enduring effects of earlier stress burden on MDD in women into old age and, in light of the increasing proportion of older women in the population, have important clinical implications for identification and treatment of those at risk for depression. Findings also underscore the need to develop resources to counteract or buffer similar stress exposure in younger generations of women. Copyright © 2009 John Wiley & Sons, Ltd. [source] A silver spoon for a golden future: long-term effects of natal origin on fitness prospects of oystercatchers (Haematopus ostralegus)JOURNAL OF ANIMAL ECOLOGY, Issue 2 2006MARTIJN VAN DE POL Summary 1Long-term effects of conditions during early development on fitness are important for life history evolution and population ecology. Using multistrata mark,recapture models on 20 years of data, we quantified the relation between rearing conditions and lifetime fitness in a long-lived shorebird, the oystercatcher (Haematopus ostralegus). We addressed specifically the relative contribution of short- and long-term effects of rearing conditions to overall fitness consequences. 2Rearing conditions were defined by differences in natal habitat quality, in which there is a clear dichotomy in our study population. In the first year of life, fledglings from high-quality natal origin had a 1·3 times higher juvenile survival. Later in life (age 3,11), individuals of high-quality natal origin had a 1·6 times higher adult prebreeder survival. The most striking effect of natal habitat quality was that birds that were reared on high-quality territories had a higher probability of settling in high-quality habitat (44% vs. 6%). Lifetime reproductive success of individuals born in high-quality habitat was 2·2 times higher than that of individuals born in low-quality habitat. This difference increased further when fitness was calculated over several generations, due to a correlation between the quality of rearing conditions of parents and their offspring. 3Long-term effects of early conditions contributed more to overall fitness differences as short-term consequences, contrary to common conceptions on this issue. 4This study illustrates that investigating only short-term effects of early conditions can lead to the large underestimation of fitness consequences. We discuss how long-term consequences of early conditions may affect settlement decisions and source,sink population interactions. [source] Demographic vital rates determine the performance advantage of crop,wild hybrids in lettuceJOURNAL OF APPLIED ECOLOGY, Issue 6 2005DANNY A. P. HOOFTMAN Summary 1Hybridization seems possible for many crop species after pollen transfer from crops to wild relatives in the surrounding vegetation. Subsequent introgression of crop-specific traits into wild relatives could lead to invasive introgressants. This process has become a public concern following the introduction of genetically modified (GM) crops. Until now, few studies have used demographic vital rates to compare the performance of hybrids with their wild relatives. 2We created second-generation (S1 and BC1) hybrids between the non-transgenic crop Lactuca sativa and its entirely cross-fertile wild relative Lactuca serriola. Seeds of parents and hybrids were individually sown in field plots at three different locations. Next to germination and survival, we measured a range of single fitness components and morphological traits. We also compared observed phenotypes to phenotypes theoretically expected, according to different inheritance scenarios. 3Phenotypes of both hybrid classes resembled L. serriola closely, and more than theoretically expected. However, demographic vital rates, i.e. germination and survival of hybrids were much higher than in L. serriola. 4Our results indicate that hybrids between crop and wild Lactuca are phenotypically indistinguishable from the wild relative and thus will largely remain unnoticed when they occur. However, these hybrids could potentially become invasive because of substantial differences in vital rates and seeds returned per seed sown. 5Synthesis and applications. A comparative study on single fitness components, such as seed production, alone would not have revealed the performance advantage of crop,wild hybrids in Lactuca. Therefore, studying demographic vital rates of hybrids and back-crosses to test for long-term consequences of hybridization should be part of any risk assessment of GM crops. Demographic vital rates are also important for the development of predictive modelling tools that can be employed to test the individual- and population-level consequences of new-to-add traits. [source] Changes in population biology of two succulent shrubs along a grazing gradientJOURNAL OF APPLIED ECOLOGY, Issue 4 2003Corinna Riginos Summary 1Heavy livestock grazing in Namaqualand, South Africa, is threatening the region's unique diversity of succulent shrubs. This is especially true in the communally managed lands, where grazing is centred around fixed enclosures (stockposts) in which animals stay overnight. In this study we set out to determine the effects of a semi-permanent stockpost on the composition of the surrounding vegetation and the mechanisms by which grazing limits the persistence of leaf-succulent shrub populations. 2We used the grazing gradient created by a stockpost to examine the impacts of grazing on vegetation composition and changes in mortality, reproductive output and seedling establishment for the leaf-succulent species Ruschia robusta and Cheiridopsis denticulata. 3Vegetation composition was found to change from a community dominated by the unpalatable shrub Galenia africana at high grazing intensities to a community dominated by the palatable leaf-succulent shrub R. robusta at lower grazing intensities. 4Mortality of the leaf-succulents R. robusta and C. denticulata was high at the sites closest to the stockpost, while fruit production and seedling germination were substantially reduced over distances of 800 m and 2 km for the two species, respectively. Seedling establishment was not limited by either grazing or microsite availability. Thus reduction in reproductive output is the greatest impact of heavy grazing on these two species. 5Synthesis and applications. This study demonstrates that marked zonation in vegetation composition and population biology can develop around a fixed stockpost and that the greatest impact of grazing on the two leaf-succulent species studied is the suppression of flower and fruit production. Consistent suppression of reproductive output could have long-term consequences for the persistence of succulent shrub populations in the heavily grazed communal lands of Namaqualand. We recommend that (i) herders should be encouraged to relocate their stockposts regularly to prevent the development of centres of degradation, and (ii) areas should be relieved periodically of all grazing pressure to allow for successful seed set of native shrubs. [source] The function of the Egr1 transcription factor in cartilage formation and adaptation to microgravity in zebrafish, Danio rerioJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2010M. Muller Summary Osteoporosis is one of the major concerns for an ageing human population and for passengers on long-term space flights. Teleosts represent a potentially interesting alternative for studying bone physiology. In zebrafish (Danio rerio), the cartilaginous elements that form the pharyngeal arches derive from cranial neural crest cells, whose proper patterning and morphogenesis require reciprocal interactions with other tissue types such as pharyngeal endoderm, ectoderm and mesoderm. We show how the zebrafish can be used to study the function of signal transduction pathways, such as the Fgf pathway, or that of particular genes, such as the zinc finger transcription factor Egr1, in pharyngeal skeleton formation and maintenance. We investigate the changes caused by microgravity and chemical treatments on zebrafish. We analyze early gene expression modification using whole genome microarray experiments and the long-term consequences by staining bone structures. [source] Phytohaemagglutinin injection has a long-lasting effect on immune cellsJOURNAL OF AVIAN BIOLOGY, Issue 5 2009Tuul Sarv Measurement of phytohaemagglutinin (PHA)-induced skin swelling is the most popular assay of immune function in avian studies. The mechanisms causing swelling have been relatively well studied; however, very little is known about the potential long term physiological effects of PHA. Here we show that injection of PHA into patagium of captive greenfinches Carduelis chloris increases the concentration of heterophils (phagocytic cells of the innate immune response) in the peripheral blood for at least 30,days. Such long-term consequences should be taken into account when using PHA skin test in studies monitoring changes in individual physiological condition and/or immune status. [source] | ||||||||||||||||||||||||||||||||||||||||||||||