210 research outputs found

    Ultrarelativistic electron beam spatial size estimation from angular distribution emission in thin crystals

    Get PDF
    The use of ultrarelativistic electron (positron) emission in thin crystals to estimate particle beam spatial sizes for projected electron–positron colliders is proposed.The existing position-sensitive X-ray range detectors restrict the minimum value of the measured beam size to a level of approximately 10 μm, which is far greater than the planned sizes of collider beam

    Improvement of pain and regional osteoporotic changes in the foot and ankle by low-dose bisphosphonate therapy for complex regional pain syndrome type I: a case series

    Get PDF
    <p>Abstract</p> <p>Introduction</p> <p>Complex regional pain syndrome is characterized by pain, allodynia, hyperalgesia, edema, signs of vasomotor instability, movement disorders, joint stiffness, and regional osteopenia. It is recognized to be difficult to treat, despite various methods of treatment, including physiotherapy, calcitonin, corticosteroids, sympathetic blockade, and nonsteroidal anti-inflammatory drugs. Pathophysiologically, complex regional pain syndrome reveals enhanced regional bone resorption and high bone turnover, and so bisphosphonates, which have a potent inhibitory effect on bone resorption, were proposed for the treatment of complex regional pain syndrome.</p> <p>Case presentation</p> <p>A 48-year-old Japanese man with complex regional pain syndrome type I had severe right ankle pain with a visual analog scale score of 59 out of 100 regardless of treatment with physiotherapy and nonsteroidal anti-inflammatory drugs for five months. Radiographs showed marked regional osteoporotic changes and bone scintigraphy revealed a marked increase in radioactivity in his ankle. One month after the start of oral administration of risedronate (2.5 mg per day), his bone pain had fallen from a VAS score of 59 out of 100 to 18 out of 100. Bone scintigraphy at 12 months showed a marked reduction in radioactivity to a level comparable to that in his normal, left ankle. On the basis of these results, the treatment was discontinued at 15 months. At 32 months, our patient had almost no pain and radiographic findings revealed that the regional osteoporotic change had returned to normal.</p> <p>A second 48-year-old Japanese man with complex regional pain syndrome type I had severe right foot pain with a visual analog scale score of 83 out of 100 regardless of treatment with physiotherapy and nonsteroidal anti-inflammatory drugs for nine months. Radiographs showed regional osteoporotic change in his phalanges, metatarsals, and tarsals, and bone scintigraphy revealed a marked increase in radioactivity in his foot. One month after the start of oral administration of alendronate (35 mg per week), his bone pain had fallen from a visual analog scale score of 83 out of 100 to 30 out of 100 and, at nine months, was further reduced to 3 out of 100. The treatment was discontinued at 15 months because of successful pain reduction. At 30 months, our patient had no pain and the radiographic findings revealed marked improvement in regional osteoporotic changes.</p> <p>Conclusions</p> <p>We believe low-dose oral administration of bisphosphonate is worth considering for the treatment of idiopathic complex regional pain syndrome type I accompanied by regional osteoporotic change.</p

    M19 Modulates Skeletal Muscle Differentiation and Insulin Secretion in Pancreatic β-Cells through Modulation of Respiratory Chain Activity

    Get PDF
    Mitochondrial dysfunction due to nuclear or mitochondrial DNA alterations contributes to multiple diseases such as metabolic myopathies, neurodegenerative disorders, diabetes and cancer. Nevertheless, to date, only half of the estimated 1,500 mitochondrial proteins has been identified, and the function of most of these proteins remains to be determined. Here, we characterize the function of M19, a novel mitochondrial nucleoid protein, in muscle and pancreatic β-cells. We have identified a 13-long amino acid sequence located at the N-terminus of M19 that targets the protein to mitochondria. Furthermore, using RNA interference and over-expression strategies, we demonstrate that M19 modulates mitochondrial oxygen consumption and ATP production, and could therefore regulate the respiratory chain activity. In an effort to determine whether M19 could play a role in the regulation of various cell activities, we show that this nucleoid protein, probably through its modulation of mitochondrial ATP production, acts on late muscle differentiation in myogenic C2C12 cells, and plays a permissive role on insulin secretion under basal glucose conditions in INS-1 pancreatic β-cells. Our results are therefore establishing a functional link between a mitochondrial nucleoid protein and the modulation of respiratory chain activities leading to the regulation of major cellular processes such as myogenesis and insulin secretion

    Signal transduction events induced by extracellular guanosine 5′triphosphate in excitable cells

    Get PDF
    A better understanding of the physiological effects of guanosine-based purines should help clarify the complex subject of purinergic signalling. We studied the effect of extracellular guanosine 5′triphosphate (GTP) on the differentiation of two excitable cell lines that both have specific binding sites for GTP: PC12 rat pheochromocytoma cells and C2C12 mouse skeletal muscle cells. PC12 cells can be differentiated into fully functional sympathetic-like neurons with 50′00 ng ml−1 of nerve growth factor, whereas serum starvation causes C2C12 cells to differentiate into myotubes showing functional excitation–contraction coupling, with the expression of myosin heavy chain proteins. Our results show that GTP enhances the differentiation of both of these excitable cell lines. The early events in guanosine-based purine signal transduction appear to involve an increase in intracellular Ca2+ levels and membrane hyperpolarization. We further investigated the early activation of extracellular-regulated kinases and phosphoinositide 3-kinase in GTP-stimulated PC12 and C2C12 cells, respectively. We found that GTP promotes the activation of both kinases. Together, our results suggest that, even if there are some differences in the signalling pathways, GTP-induced differentiation in both cell lines is dependent on an increase in intracellular Ca2+

    Derangement of body representation in complex regional pain syndrome: report of a case treated with mirror and prisms

    Get PDF
    Perhaps the most intriguing disorders of body representation are those that are not due to primary disease of brain tissue. Strange and sometimes painful phantom limb sensations can result from loss of afference to the brain; and Complex Regional Pain Syndrome (CRPS)—the subject of the current report—can follow limb trauma without pathology of either the central or peripheral nervous system. This enigmatic and vexing condition follows relatively minor trauma, and can result in enduring misery and a useless limb. It manifests as severe pain, autonomic dysfunction, motor disability and ‘neglect-like’ symptoms with distorted body representation. For this special issue on body representation we describe the case of a patient suffering from CRPS, including symptoms suggesting a distorted representation of the affected limb. We report contrasting effects of mirror box therapy, as well as a new treatment—prism adaptation therapy—that provided sustained pain relief and reduced disability. The benefits were contingent upon adapting with the affected limb. Other novel observations suggest that: (1) pain may be a consequence, not the cause, of a disturbance of body representation that gives rise to the syndrome; (2) immobilisation, not pain, may precipitate this reorganisation of somatomotor circuits in susceptible individuals; and (3) limitation of voluntary movement is neither due to pain nor to weakness but, rather, to derangement of body representation which renders certain postures from the repertoire of hand movements inaccessible

    A Non-Targeted Approach Unravels the Volatile Network in Peach Fruit

    Get PDF
    Volatile compounds represent an important part of the plant metabolome and are of particular agronomic and biological interest due to their contribution to fruit aroma and flavor and therefore to fruit quality. By using a non-targeted approach based on HS-SPME-GC-MS, the volatile-compound complement of peach fruit was described. A total of 110 volatile compounds (including alcohols, ketones, aldehydes, esters, lactones, carboxylic acids, phenolics and terpenoids) were identified and quantified in peach fruit samples from different genetic backgrounds, locations, maturity stages and physiological responses. By using a combination of hierarchical cluster analysis and metabolomic correlation network analysis we found that previously known peach fruit volatiles are clustered according to their chemical nature or known biosynthetic pathways. Moreover, novel volatiles that had not yet been described in peach were identified and assigned to co-regulated groups. In addition, our analyses showed that most of the co-regulated groups showed good intergroup correlations that are therefore consistent with the existence of a higher level of regulation orchestrating volatile production under different conditions and/or developmental stages. In addition, this volatile network of interactions provides the ground information for future biochemical studies as well as a useful route map for breeding or biotechnological purposes

    The association between baseline persistent pain and weight change in patients attending a specialist weight management service

    Get PDF
    To quantify the influence of baseline pain levels on weight change at one-year follow-up in patients attending a National Health Service specialist weight management programme.We compared one-year follow-up weight (body mass) change between patient sub-groups of none-to-mild, moderate, and severe pain at baseline. A mean sub-group difference in weight change of ≥5kg was considered clinically relevant.Of the 141 complete cases, n = 43 (30.5%) reported none-to-mild pain, n = 44 (31.2%) reported moderate pain, and n = 54 (38.3%) reported severe pain. Covariate-adjusted mean weight loss (95%CI) was similar for those with none-to-mild (8.1kg (4.2 to 12.0kg)) and moderate pain (8.3kg (4.9 to 11.7kg). The mean weight loss of 3.0kg (-0.4 to 6.4kg) for the severe pain group was 5.1kg (-0.6 to 10.7, p = 0.08) lower than the none-to-mild pain group and 5.3kg (0.4 to 10.2kg, p = 0.03) lower than the moderate pain group.Patients with severe pain upon entry to a specialist weight management service in England achieve a smaller mean weight loss at one-year follow-up than those with none-to-moderate pain. The magnitude of the difference in mean weight loss was clinically relevant, highlighting the importance of addressing severe persistent pain in obese patients undertaking weight management programmes
    corecore