192 research outputs found

    Roles of TRPV1 and neuropeptidergic receptors in dorsal root reflex-mediated neurogenic inflammation induced by intradermal injection of capsaicin

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    <p>Abstract</p> <p>Background</p> <p>Acute cutaneous neurogenic inflammation initiated by activation of transient receptor potential vanilloid-1 (TRPV<sub>1</sub>) receptors following intradermal injection of capsaicin is mediated mainly by dorsal root reflexes (DRRs). Inflammatory neuropeptides are suggested to be released from primary afferent nociceptors participating in inflammation. However, no direct evidence demonstrates that the release of inflammatory substances is due to the triggering of DRRs and how activation of TRPV<sub>1 </sub>receptors initiates neurogenic inflammation via triggering DRRs.</p> <p>Results</p> <p>Here we used pharmacological manipulations to analyze the roles of TRPV<sub>1 </sub>and neuropeptidergic receptors in the DRR-mediated neurogenic inflammation induced by intradermal injection of capsaicin. The degree of cutaneous inflammation in the hindpaw that followed capsaicin injection was assessed by measurements of local blood flow (vasodilation) and paw-thickness (edema) of the foot skin in anesthetized rats. Local injection of capsaicin, calcitonin gene-related peptide (CGRP) or substance P (SP) resulted in cutaneous vasodilation and edema. Removal of DRRs by either spinal dorsal rhizotomy or intrathecal administration of the GABA<sub>A </sub>receptor antagonist, bicuculline, reduced dramatically the capsaicin-induced vasodilation and edema. In contrast, CGRP- or SP-induced inflammation was not significantly affected after DRR removal. Dose-response analysis of the antagonistic effect of the TRPV<sub>1 </sub>receptor antagonist, capsazepine administered peripherally, shows that the capsaicin-evoked inflammation was inhibited in a dose-dependent manner, and nearly completely abolished by capsazepine at doses between 30–150 μg. In contrast, pretreatment of the periphery with different doses of CGRP<sub>8–37 </sub>(a CGRP receptor antagonist) or spantide I (a neurokinin 1 receptor antagonist) only reduced the inflammation. If both CGRP and NK<sub>1 </sub>receptors were blocked by co-administration of CGRP<sub>8–37 </sub>and spantide I, a stronger reduction in the capsaicin-initiated inflammation was produced.</p> <p>Conclusion</p> <p>Our data suggest that 1) the generation of DRRs is critical for driving the release of neuropeptides antidromically from primary afferent nociceptors; 2) activation of TRPV<sub>1 </sub>receptors in primary afferent nociceptors following intradermal capsaicin injection initiates this process; 3) the released CGRP and SP participate in neurogenic inflammation.</p

    Public appraisal of government efforts and participation intent in medico-ethical policymaking in Japan: a large scale national survey concerning brain death and organ transplant

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    BACKGROUND: Public satisfaction with policy process influences the legitimacy and acceptance of policies, and conditions the future political process, especially when contending ethical value judgments are involved. On the other hand, public involvement is required if effective policy is to be developed and accepted. METHODS: Using the data from a large-scale national opinion survey, this study evaluates public appraisal of past government efforts to legalize organ transplant from brain-dead bodies in Japan, and examines the public's intent to participate in future policy. RESULTS: A relatively large percentage of people became aware of the issue when government actions were initiated, and many increasingly formed their own opinions on the policy in question. However, a significant number (43.3%) remained unaware of any legislative efforts, and only 26.3% of those who were aware provided positive appraisals of the policymaking process. Furthermore, a majority of respondents (61.8%) indicated unwillingness to participate in future policy discussions of bioethical issues. Multivariate analysis revealed the following factors are associated with positive appraisals of policy development: greater age; earlier opinion formation; and familiarity with donor cards. Factors associated with likelihood of future participation in policy discussion include younger age, earlier attention to the issue, and knowledge of past government efforts. Those unwilling to participate cited as their reasons that experts are more knowledgeable and that the issues are too complex. CONCLUSIONS: Results of an opinion survey in Japan were presented, and a set of factors statistically associated with them were discussed. Further efforts to improve policy making process on bioethical issues are desirable

    Perceiving What Is Reachable Depends on Motor Representations: Evidence from a Transcranial Magnetic Stimulation Study

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    Background: Visually determining what is reachable in peripersonal space requires information about the egocentric location of objects but also information about the possibilities of action with the body, which are context dependent. The aim of the present study was to test the role of motor representations in the visual perception of peripersonal space. Methodology: Seven healthy participants underwent a TMS study while performing a right-left decision (control) task or perceptually judging whether a visual target was reachable or not with their right hand. An actual grasping movement task was also included. Single pulse TMS was delivered 80 % of the trials on the left motor and premotor cortex and on a control site (the temporo-occipital area), at 90 % of the resting motor threshold and at different SOA conditions (50ms, 100ms, 200ms or 300ms). Principal Findings: Results showed a facilitation effect of the TMS on reaction times in all tasks, whatever the site stimulated and until 200ms after stimulus presentation. However, the facilitation effect was on average 34ms lower when stimulating the motor cortex in the perceptual judgement task, especially for stimuli located at the boundary of peripersonal space. Conclusion: This study provides the first evidence that brain motor area participate in the visual determination of what is reachable. We discuss how motor representations may feed the perceptual system with information about possibl

    Omeprazole Inhibits Proliferation and Modulates Autophagy in Pancreatic Cancer Cells

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    BACKGROUND: Omeprazole has recently been described as a modulator of tumour chemoresistance, although its underlying molecular mechanisms remain controversial. Since pancreatic tumours are highly chemoresistant, a logical step would be to investigate the pharmacodynamic, morphological and biochemical effects of omeprazole on pancreatic cancer cell lines. METHODOLOGY/PRINCIPAL FINDINGS: Dose-effect curves of omeprazole, pantoprazole, gemcitabine, 5-fluorouracil and the combinations of omeprazole and 5-fluorouracil or gemcitabine were generated for the pancreatic cancer cell lines MiaPaCa-2, ASPC-1, Colo357, PancTu-1, Panc1 and Panc89. They revealed that omeprazole inhibited proliferation at probably non-toxic concentrations and reversed the hormesis phenomena of 5-fluorouracil. Electron microscopy showed that omeprazole led to accumulation of phagophores and early autophagosomes in ASPC-1 and MiaPaCa-2 cells. Signal changes indicating inhibited proliferation and programmed cell death were found by proton NMR spectroscopy of both cell lines when treated with omeprazole which was identified intracellularly. Omeprazole modulates the lysosomal transport pathway as shown by Western blot analysis of the expression of LAMP-1, Cathepsin-D and β-COP in lysosome- and Golgi complex containing cell fractions. Acridine orange staining revealed that the pump function of the vATPase was not specifically inhibited by omeprazole. Gene expression of the autophagy-related LC3 gene as well as of Bad, Mdr-1, Atg12 and the vATPase was analysed after treatment of cells with 5-fluorouracil and omeprazole and confirmed the above mentioned results. CONCLUSIONS: We hypothesise that omeprazole interacts with the regulatory functions of the vATPase without inhibiting its pump function. A modulation of the lysosomal transport pathway and autophagy is caused in pancreatic cancer cells leading to programmed cell death. This may circumvent common resistance mechanisms of pancreatic cancer. Since omeprazole use has already been established in clinical practice these results could lead to new clinical applications

    Re-examination of the Controversial Coexistence of Traumatic Brain Injury and Posttraumatic Stress Disorder: Misdiagnosis and Self-Report Measures

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    The coexistence of traumatic brain injury (TBI) and posttraumatic stress disorder (PTSD) remains a controversial issue in the literature. To address this controversy, we focused primarily on the civilian-related literature of TBI and PTSD. Some investigators have argued that individuals who had been rendered unconscious or suffered amnesia due to a TBI are unable to develop PTSD because they would be unable to consciously experience the symptoms of fear, helplessness, and horror associated with the development of PTSD. Other investigators have reported that individuals who sustain TBI, regardless of its severity, can develop PTSD even in the context of prolonged unconsciousness. A careful review of the methodologies employed in these studies reveals that investigators who relied on clinical interviews of TBI patients to diagnose PTSD found little or no evidence of PTSD. In contrast, investigators who relied on PTSD questionnaires to diagnose PTSD found considerable evidence of PTSD. Further analysis revealed that many of the TBI patients who were initially diagnosed with PTSD according to self-report questionnaires did not meet the diagnostic criteria for PTSD upon completion of a clinical interview. In particular, patients with severe TBI were often misdiagnosed with PTSD. A number of investigators found that many of the severe TBI patients failed to follow the questionnaire instructions and erroneously endorsed PTSD symptoms because of their cognitive difficulties. Because PTSD questionnaires are not designed to discriminate between PTSD and TBI symptoms or determine whether a patient's responses are accurate or exaggerated, studies that rely on self-report questionnaires to evaluate PTSD in TBI patients are at risk of misdiagnosing PTSD. Further research should evaluate the degree to which misdiagnosis of PTSD occurs in individuals who have sustained mild TBI

    Toward an integration of landscape and food web ecology: The dynamics of spatially subsidized food webs

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    We focus on the implications of movement, landscape variables, and spatial heterogeneity for food web dynamics. Movements of nutrients, detritus, prey, and consumers among habitats are ubiquitous in diverse biomes and can strongly influence population, consumer-resource, food web, and community dynamics. Nutrient and detrital subsidies usually increase primary and secondary productivity, both directly and indirectly. Prey subsidies, by movement of either prey or predators, usually enhance predator abundance beyond what local resources can support. Top-down effects occur when spatially subsidized consumers affect local resources by suppressing key resources and occasionally by initiating trophic cascades. Effects on community dynamics vary with the relative amount of input, the trophic roles of the mobile and recipient entities, and the local food web structure. Landscape variables such as the perimeter/area ratio of the focal habitat, permeability of habitat boundaries, and relative productivity of trophically connected habitats affect the degree and importance of spatial subsidization

    Improving outcomes for women aged 70 years or above with early breast cancer: research programme including a cluster RCT

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    Background In breast cancer management, age-related practice variation is widespread, with older women having lower rates of surgery and chemotherapy than younger women, based on the premise of reduced treatment tolerance and benefit. This may contribute to inferior outcomes. There are currently no age- and fitness-stratified guidelines on which to base treatment recommendations. Aim We aimed to optimise treatment choice and outcomes for older women (aged ≥ 70 years) with operable breast cancer. Objectives Our objectives were to (1) determine the age, comorbidity, frailty, disease stage and biology thresholds for endocrine therapy alone versus surgery plus adjuvant endocrine therapy, or adjuvant chemotherapy versus no chemotherapy, for older women with breast cancer; (2) optimise survival outcomes for older women by improving the quality of treatment decision-making; (3) develop and evaluate a decision support intervention to enhance shared decision-making; and (4) determine the degree and causes of treatment variation between UK breast units. Design A prospective cohort study was used to determine age and fitness thresholds for treatment allocation. Mixed-methods research was used to determine the information needs of older women to develop a decision support intervention. A cluster-randomised trial was used to evaluate the impact of this decision support intervention on treatment choices and outcomes. Health economic analysis was used to evaluate the cost–benefit ratio of different treatment strategies according to age and fitness criteria. A mixed-methods study was used to determine the degree and causes of variation in treatment allocation. Main outcome measures The main outcome measures were enhanced age- and fitness-specific decision support leading to improved quality-of-life outcomes in older women (aged ≥ 70 years) with early breast cancer
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