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991.
Lauvin MA Martineau J Destrieux C Andersson F Bonnet-Brilhault F Gomot M El-Hage W Cottier JP 《Diagnostic and interventional imaging》2012,93(3):139-147
Autism is a pervasive disorder of childhood development. Polymorphous clinical profiles combining various degrees of communication and social interaction with restricted and stereotyped behaviour are grouped under the heading of 'autism spectrum disorders' (ASD). Many teams are trying to pick out the underlying cerebral abnormalities in order to understand the neuronal networks involved in relationships with others. Here we review the morphological, spectroscopic and functional abnormalities in the amygdala-hippocampal circuit, the caudate nuclei, the cerebellum, and the frontotemporal regions, which have been described in subjects with ASD. White matter abnormalities have also been described in diffusion tensor imaging, leading to suspected damage to the subjacent neural networks, such as mirror neurones or the social brain. 相似文献
992.
Nilesh M. Agalave Max Larsson Sally Abdelmoaty Jie Su Azar Baharpoor Peter Lundbäck Karin Palmblad Ulf Andersson Helena Harris Camilla I. Svensson 《Pain》2014
Extracellular high mobility group box-1 protein (HMGB1) plays important roles in the pathogenesis of nerve injury- and cancer-induced pain. However, the involvement of spinal HMGB1 in arthritis-induced pain has not been examined previously and is the focus of this study. Immunohistochemistry showed that HMGB1 is expressed in neurons and glial cells in the spinal cord. Subsequent to induction of collagen antibody-induced arthritis (CAIA), Hmgb1 mRNA and extranuclear protein levels were significantly increased in the lumbar spinal cord. Intrathecal (i.t.) injection of a neutralizing anti-HMGB1 monoclonal antibody or recombinant HMGB1 box A peptide (Abox), which each prevent extracellular HMGB1 activities, reversed CAIA-induced mechanical hypersensitivity. This occurred during ongoing joint inflammation as well as during the postinflammatory phase, indicating that spinal HMGB1 has an important function in nociception persisting beyond episodes of joint inflammation. Importantly, only HMGB1 in its partially oxidized isoform (disulfide HMGB1), which activates toll-like receptor 4 (TLR4), but not in its fully reduced or fully oxidized isoforms, evoked mechanical hypersensitivity upon i.t. injection. Interestingly, although both male and female mice developed mechanical hypersensitivity in response to i.t. HMGB1, female mice recovered faster. Furthermore, the pro-nociceptive effect of i.t. injection of HMGB1 persisted in Tlr2- and Rage-, but was absent in Tlr4-deficient mice. The same pattern was observed for HMGB1-induced spinal microglia and astrocyte activation and cytokine induction. These results demonstrate that spinal HMGB1 contributes to nociceptive signal transmission via activation of TLR4 and point to disulfide HMGB1 inhibition as a potential therapeutic strategy in treatment of chronic inflammatory pain. 相似文献
993.
Marsell R Sisask G Nilsson Y Sundgren-Andersson AK Andersson U Larsson S Nilsson O Ljunggren O Jonsson KB 《BONE》2012,50(3):619-627
Glycogen synthase kinase 3β (GSK-3β) actions are central in the canonical Wnt pathway, important in many biological processes and a potential drug target for treating several diseases. It is appreciated that a balanced Wnt canonical signaling is crucial for the maintenance of normal bone mass. In this study we investigated the effects of a potent orally active GSK-3 inhibitor, AZD2858, on bone mass in rats. Treatment (1 μM) of human osteoblast cells with AZD2858 in vitro increased β-catenin levels after a short period of time. In rats, oral AZD2858 treatment caused a dose-dependent increase in trabecular bone mass compared to control after a two-week treatment with a maximum effect at a dose of 20 mg/kg once daily (total BMC: 172% of control; p<0.001). A small but significant effect was also seen at cortical sites (total BMC: 111% of control; p<0.001). Biomechanical testing demonstrated an increase in both vertebral compression strength at a dose of 20 mg/kg once daily (Load at failure: 370% of control, p<0.001) and diaphyseal strength of femora subjected to a three point bending test (Load at failure: 115% of control; p<0.01). Furthermore, histomorphometry showed a dramatic increase in bone formation indices, and serum markers of both bone formation (Osteocalcin, 146% of control; p<0.001) and resorption (CTX, 189% of control; p<0.001) were elevated. Our conclusion is that a GSK-3 inhibitor drug may prove effective as an anabolic strategy in the treatment of diseases characterized by low bone mass, since AZD2858 has extensive bone building effects at predominantly trabecular sites. 相似文献
994.
Richard A. Deyo Samuel F. Dworkin Dagmar Amtmann Gunnar Andersson David Borenstein Eugene Carragee John Carrino Roger Chou Karon Cook Anthony DeLitto Christine Goertz Partap Khalsa John Loeser Sean Mackey James Panagis James Rainville Tor Tosteson Dennis Turk Michael Von Korff Debra K. Weiner 《Journal of manipulative and physiological therapeutics》2014
Objectives
Despite rapidly increasing intervention, functional disability due to chronic low back pain (cLBP) has increased in recent decades. We often cannot identify mechanisms to explain the major negative impact cLBP has on patients' lives. Such cLBP is often termed nonspecific and may be due to multiple biologic and behavioral etiologies. Researchers use varied inclusion criteria, definitions, baseline assessments, and outcome measures, which impede comparisons and consensus. The purpose of this article is to disseminate the report of the National Institutes of Health (NIH) task force on research standards for cLBP.Methods
The NIH Pain Consortium charged a research task force (RTF) to draft standards for research on cLBP. The resulting multidisciplinary panel developed a 3-stage process, each with a 2-day meeting.Results
The panel recommended using 2 questions to define cLBP; classifying cLBP by its impact (defined by pain intensity, pain interference, and physical function); use of a minimal data set to describe research subjects (drawing heavily on the Patient Reported Outcomes Measurement Information System methodology); reporting “responder analyses” in addition to mean outcome scores; and suggestions for future research and dissemination. The Pain Consortium has approved these recommendations, which investigators should incorporate into NIH grant proposals.Conclusions
The RTF believes that these recommendations will advance the field, help to resolve controversies, and facilitate future research addressing the genomic, neurologic, and other mechanistic substrates of cLBP. Greater consistency in reporting should facilitate comparisons among studies and the development of phenotypes. We expect the RTF recommendations will become a dynamic document and undergo continual improvement. 相似文献995.
Mengtao Zhou Bicheng Chen Hongwei Sun Xiaolei Chen Zhengping Yu Hongqi Shi Jiangao Yao Zhengkeng Xu Qiyu Zhang Roland Andersson 《Pancreatology》2013,13(3):212-215
ObjectiveOur aim was to investigate the efficiency of continuous regional intra-arterial infusion (CRAI) with antisecretory agents and antibiotics in the treatment of infected pancreatic necrosis.Materials and methodsCRAI was used as a new clinical technique to treat acute pancreatitis patients during a 4-year period at the First Affiliated Hospital, Wenzhou Medical College, China. In this retrospective study, thirty-four patients with proven infected pancreatic necrosis were included. Twelve patients were treated with CRAI, and were matched according to age, sex, APACHE II scores, Ranson scores and remote organ dysfunction, with 22 patients with IPN treated surgically. The clinical outcome following surgery and CRAI were compared.ResultsNo difference was found between the two groups when comparing age, gender, APACHE II scores, Ranson scores and remote organ dysfunction (p > 0.05). The patients treated with CRAI had a lower incidence of complications (33.3% vs 72.7%), duration of hospitalization (27.1 ± 4.7 days vs 43.0 ± 12.0 days) and cost of hospitalization (4.09 ± 1.64 thousand RMB vs 8.77 ± 3.74 thousand RMB) as compared to patients treated with surgery (p < 0.05). The survival rate was significantly higher in the CRAI group as compared to the surgical group (91.7% vs 63.6%; p < 0.01). However, the two groups had similar rates of concomitant operative treatment and incidence of remote organ dysfunction (p > 0.05).ConclusionsCRAI or CRAI in combination with abscess drainage seemingly improve the clinical outcome in patients with infected pancreatic necrosis. Further confirmative prospective randomized multicenter studies are warranted prior to broad introduction of the CRAI concept. 相似文献
996.
L. Loizou N. Albiin C. Ansorge M. Andersson R. Segersvärd B. Leidner A. Sundin L. Lundell N. Kartalis 《Pancreatology》2013,13(6):570-575
Background/objectivesDuctal adenocarcinoma in the head of the pancreas (PDAC) is usually unresectable at the time of diagnosis due to the involvement of the peripancreatic vessels. Various preoperative classification algorithms have been developed to describe the relationship of the tumor to these vessels, but most of them lack a surgically based approach. We present a CT-based classification algorithm for PDAC based on surgical resectability principles with a focus on interobserver variability.MethodsThirty patients with PDAC undergoing pancreaticoduodenectomy were examined by using a standard CT protocol. Nine radiologists, representing three different levels of expertise, evaluated the CT examinations and the tumors were classified into four categories (A–D) according to the proposed system. For the interobserver agreement, the Intraclass Correlation Coefficient (ICC) was estimated.ResultsThe overall ICC was 0.94 and the ICCs among the trainees, experienced radiologists, and experts were 0.85, 0.76, and 0.92, respectively. All tumors classified as category A1 showed no signs of vascular invasion at surgery. In category A2, 40% of the tumors had corresponding infiltration and required resection of the superior mesenteric vein/portal vein (SMV/PV). One of two tumors in category B2 and two of three in category C required SMV/PV resection. All six patients in category D had both arterial and venous involvement.ConclusionThere is almost perfect agreement among radiologists with different levels of expertise in regards to the local staging of PDAC. For tumors in a more advanced preoperative category, an increased risk for vascular involvement was noticed at surgery. 相似文献
997.
998.
Borje S. Andersson 《Hematology (Amsterdam, Netherlands)》2013,18(3):173-177
The basis for the vast recognition spectrum of the T-cell receptor (TCR) can be determined by the rearrangement and recombination of the variable, diversity and joining regions of the variable portions of β (B) and α (A) chains as well as their recombination and modification. Analysis of the TCR rearrangement has been routinely used to detect clonality for the diagnosis of lymphoid malignancies. However, molecular analysis of the TCR repertoire can be a powerful tool in the study of T-cell responses to pathogens and in autoimmune diseases. The concept of the oligoclonality in the context of cellular immune responses is based on the presence of immunodominant T-cell clones within distinct T-cell subpopulations used for analysis. Under normal circumstances, a limited number of clones undergo periodic expansions in reaction to foreign antigens. Under pathologic conditions, though, the derailment of immune regulation allows expansions of specific and potentially pathogenic T-cell clones. For example, large granular lymphocyte (LGL) leukemia illustrates an extreme expansion of a single T-cell clone associated with a distinct autoimmune pathology, which suggests an exaggerated clonal response to a specific antigenic target. In immune-mediated bone marrow failure syndromes, clonal rearrangement of the TCR cannot be detected in unseparated blood or marrow. Nevertheless, individual T-cell clones can significantly expand and may allow for demonstration of oligoclonality in selected T-cell populations. These subpopulations are defined, for example, by a specific β (B)-chain usage or other phenotypic markers. Given the diversity of the TCR recognition spectrum, the task of identifying immunodominant clonotypes derived from unique complementarity determining region-3 (CDR3) sequences is very complex. However, expanded T-cell clones likely represent immunodominant responses which can be detected on the molecular level using analysis of the individual TCR VB-chain representation, CDR3 size fragment skewing, and determination of the frequency of individual clonotypic sequences. In the future, TCR VB clonotypes may be applied as a diagnostic tool, analogous to serologic markers. As an investigative tool in hematology, molecular analysis of the TCR utilization pattern and the detection of immunodominant clonotypes represents a novel approach in the study of immune-mediated hematologic diseases, such as aplastic anemia (AA), some forms of myelodysplasia (MDS), anti-leukemic immune surveillance, graft-versus-leukemia effects and graft-versus-host disease (GvHD). 相似文献
999.
1000.
Ellen Andersson Jakob Axelsson Lars Christian Pedersen Torben Elm 《Scandinavian journal of gastroenterology》2013,48(6):765-770
Objective. Acute pancreatitis starts as an autodigestive process restricted to the pancreas and progresses to a systemic inflammation via cytokine release into the blood stream. Several inhibitors of the coagulation cascade, including active-site-inactivated factor VIIa, have shown anti-inflammatory properties in other inflammatory models than acute pancreatitis. Free radical scavengers have proven useful in reducing the oxidative damage during hyperinflammatory conditions. The aim of this study was to investigate whether pretreatment with FVIIai would have any effect on the multiple organ dysfunction syndrome (MODS) in severe acute pancreatitis. Material and methods. Experimental acute pancreatitis was induced by intraductal infusion of taurodeoxycholate in the pancreatic duct. The animals were pretreated with N-acetyl-cysteine and active-site-inactivated factor VIIa. Neutrophil infiltration in the lungs, ileum and colon was quantified by myeloperoxidase activity. Inflammatory markers, IL-6 and MIP-2, were measured using ELISA. Results. Tissue infiltration of neutrophils in the lungs, ileum and colon significantly increased during acute pancreatitis as compared to sham operation. These levels were reduced by pretreatment with N-acetylcysteine and active-site-inactivated factor VIIa. Levels of interleukin-6 and macrophage inflammatory protein-2 increased significantly during acute pancreatitis. Pretreatment with NAC and FVIIai reduced these levels. Conclusions. Both N-acetylcysteine and active-site-inactivated factor VIIa showed powerful anti-inflammatory properties in experimental acute pancreatitis. As they exert their effects through different physiological mechanisms, they represent potential candidates for future multimodal treatment of acute pancreatitis. 相似文献