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101.
102.
Marc Rosenbaum Virginia Andreani Tanya Kapoor Simone Herp Henrik Flach Marlena Duchniewicz Rudolf Grosschedl 《Genes & development》2014,28(11):1165-1178
MZB1 (pERp1) is a B-cell-specific and endoplasmic reticulum (ER)-localized protein implicated in antibody secretion and integrin-mediated cell adhesion. Here, we examine the role of MZB1 in vivo by conditional gene inactivation in the mouse germline and at different stages of B lymphopoiesis. Deletion of MZB1 impairs humoral immune responses and antibody secretion in plasma cells that naturally undergo ER stress. In addition, we found that experimental induction of ER stress by tunicamycin injections in mice results in a block of pro-B-cell to pre-B-cell differentiation specifically in Mzb1−/− mice. A similar developmental block was observed in Mzb1fl/flmb1Cre mice, whereby a Cre recombinase-induced genotoxic stress unmasks a role for MZB1 in the surface expression of immunoglobulin µ heavy chains (µHCs). MZB1 associates directly with the substrate-specific chaperone GRP94 (also called HSP90B1 or gp96) in an ATP-sensitive manner and is required for the interaction of GRP94 with µHCs upon ER stress. Thus, MZB1 seems to act as a substrate-specific cochaperone of GRP94 that enables proper biosynthesis of µHCs under conditions of ER stress. 相似文献
103.
Sandra Ovesen Karina Frahm Kirk Hans Linde Nielsen Henrik Nielsen 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2017,125(3):230-235
Campylobacter concisus is an emerging pathogen associated with gastrointestinal disorders such as gastroenteritis and inflammatory bowel diseases (IBD), but the species is also found in healthy subjects. The heterogeneous genome of C. concisus increases the likelihood of varying virulence between strains. Flagella motility is a crucial virulence factor for the well‐recognized Campylobacter jejuni; therefore, this study aimed to analyze the motility of C. concisus isolated from saliva, gut biopsies, and feces of patients with IBD, gastroenteritis, and healthy subjects. The motility zones of 63 isolates from 52 patients were measured after microaerobic growth in soft‐agar plates for 72 hours. The motility of C. concisus was significantly lower than that of Campylobacter jejuni and Campylobacter fetus subsp. fetus. The motility of C. concisus varied between isolates (4–22 mm), but there was no statistical significant difference between isolates from IBD patients and healthy subjects (p = 0.14). A tendency of a larger motility zones was observed for IBD gut mucosa isolates, although it did not reach statistical significance (p = 0.13), and no difference was found between oral or fecal isolates between groups. In conclusion, the varying motility of C. concisus could not be related to disease outcome or colonization sites. 相似文献
104.
Kristiane Barington Henrik Elvang Jensen Kerstin Skovgaard 《Forensic science, medicine, and pathology》2017,13(2):151-160
Determining the age of bruises and the force used to inflict the trauma is of crucial importance in both human and veterinary forensic pathology. In the present study, the expression of more than 50 different genes in subcutaneous fat and muscle tissue from experimental bruises in pigs was investigated. The aim was to evaluate if expression signatures of selected genes were capable of determining bruises according to age and the force of impact. Eighteen experimental pigs were anesthetized, and on each animal four blunt traumas were inflicted on the back with a low, moderate or high force. The pigs were euthanized from 1 to 10 h after infliction of the trauma and subcutaneous fat and muscle tissues were sampled. As control, subcutaneous fat and muscle tissues were sampled from two un-injured pigs. Quantitative real-time polymerase chain reaction was performed to evaluate mRNA expression of genes involved in inflammation, tissue damage and repair. Expression signatures of thirteen selected genes in subcutaneous fat but not in muscle tissue reflected the age of bruises with a precision of approximately ±2 h. Moreover, the gene expression signature in the subcutaneous fat was to some extend able to separate bruises inflicted with different forces. Expression signatures of selected genes in the subcutaneous fat will increase the precision of the age determination of bruises in pigs. Further, due to the similarity of porcine and human skin physiology and immunity, these results might also provide valuable information in human forensic science. 相似文献
105.
Benjamin V. Sandholt Antoine Collet-Billon Robert Entrekin Henrik H. Sillesen 《Ultrasound in medicine & biology》2018,44(3):670-676
We tested a novel 3-D matrix transducer with respect to inter-scan reproducibility of carotid maximum plaque thickness (MPT) and volume measurements. To improve reproducibility while focusing on the largest plaque/most diseased part of the carotid artery, we introduced a new partial plaque volume (PPV) measure centered on MPT. Total plaque volume (TPV), PPV from a 10-mm segment and MPT were measured using dedicated semi-automated software on 38 plaques from 26 patients. Inter-scan reproducibility was assessed using the t-test, Bland–Altman plots and Pearson's correlation coefficient. There was a mean difference of 0.01?mm in MPT (limits of agreement: ?0.45 to 0.42?mm, Pearson's correlation coefficient: 0.96). Both volume measurements exhibited high reproducibility, with PPV being superior (limits of agreement: ?35.3?mm3 to 33.5?mm3, Pearson's correlation coefficient: 0.96) to TPV (limits of agreement: ?88.2 to 61.5?mm3, Pearson's correlation coefficient: 0.91). The good reproducibility revealed by the present results encourages future studies on establishing plaque quantification as part of cardiovascular risk assessment and for follow-up of disease progression over time. 相似文献
106.
Rasmus Blechingberg Friis Niels Henrik Hjøllund Helle Pappot Gry Assam Taarnhøj Jesper Medom Vestergaard Halla Skuladottir 《Clinical lung cancer》2021,22(2):e169-e179
BackgroundPatient-reported outcome (PRO) measures have been increasingly implemented in routine care to aid in clinical decision-making. However, the prognostic value of PRO measures as a tool for decision making is not easily interpreted by clinicians. Our aims were to explore the prognostic value of PRO measures at disease progression and the changes in PRO measures between treatment start (baseline) and disease progression.Patients and MethodsSince 2014, patients with lung cancer have completed an electronic version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaires C30 and LC-13 before every outpatient visit at the Department of Oncology, Hospital Unit West, Jutland, Denmark. The patients’ responses were used in routine care. Patients receiving palliative antineoplastic treatment were eligible for analysis if the questionnaire had been completed at the initiation of first-line treatment and at disease progression. The prognostic value of the scores was evaluated using a Cox proportional hazard model. A P value < .01 was considered statistically significant.ResultsA total of 94 screened patients were included. At disease progression, survival could be predicted from the absolute score of the global health scale, 3 functional scales (physical, role, emotional), and 7 symptom scales (fatigue, pain, dyspnea, hemoptysis, lung cancer dyspnea, chest pain). In addition, changes in hemoptysis, dysphagia, dyspnea, and chest pain predicted for survival at progression.ConclusionPRO measures used in routine care can provide clinicians with relevant prognostic information about patients with lung cancer at disease progression. These results show the potential value of PRO measures when used in clinical decision-making. 相似文献
107.
A major goal of contemporary epilepsy research is the identification of therapies to prevent the development of recurrent seizures in individuals at risk, including those with brain injuries, infections, or neoplasms; status epilepticus; cortical dysplasias; or genetic epilepsy susceptibility. In this review we consider the evidence largely from preclinical models for the antiepileptogenic activity of a diverse range of potential therapies, including some marketed antiseizure drugs, as well as agents that act by immune and inflammatory mechanisms; reduction of oxidative stress; activation of the mammalian target of rapamycin or peroxisome proliferator-activated receptors γ pathways; effects on factors related to thrombolysis, hematopoesis, and angiogenesis; inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A reducatase; brain-derived neurotrophic factor signaling; and blockade of α2 adrenergic and cannabinoid receptors. Antiepileptogenesis refers to a therapy of which the beneficial action is to reduce seizure frequency or severity outlasting the treatment period. To date, clinical trials have failed to demonstrate that antiseizure drugs have such disease-modifying activity. However, studies in animal models with levetiracetam and ethosuximide are encouraging, and clinical trials with these agents are warranted. Other promising strategies are inhibition of interleukin 1β signaling by drugs such as VX-765; modulation of sphingosine 1-phosphate signaling by drugs such as fingolimod; activation of the mammalian target of rapamycin by drugs such as rapamycin; the hormone erythropoietin; and, paradoxically, drugs such as the α2 adrenergic receptor antagonist atipamezole and the CB1 cannabinoid antagonist SR141716A (rimonabant) with proexcitatory activity. These approaches could lead to a new paradigm in epilepsy drug therapy where treatment for a limited period prevents the occurrence of spontaneous seizures, thus avoiding lifelong commitment to symptomatic treatment. 相似文献
108.
Christopher Jantzen Christian M Madsen Jes B Lauritzen Henrik L Jørgensen 《Acta orthopaedica》2018,89(2):170-176
Background and purpose — While development in hip fracture incidence and mortality is well examined, none has yet looked at the temporal trends regarding prevalence of co-morbidities. Therefore we investigated changes in incidence of first hip fracture, co-morbidity prevalence, 30?day- and 1-year mortality in hip fracture patients in the Danish population during the period 1999 to 2012.Patients and methods — Patients >18 years admitted with a fractured hip in Denmark between 1996 and 2012 were identified with data for the period 1999–2012 being analyzed regarding prevalence of co-morbidities, incidence, and mortality.Results — 122,923 patients were identified. Incidence in the whole population declined but sex-specific analysis showed no changes for men. For the whole study population, 30-day and 1-year mortality remained unchanged. Age at time of first hip fracture also remained unchanged. Of the included co-morbidities a decrease in prevalence of malignancy and dementia in women was found while there was an increase in the prevalence of all remaining co-morbidities, except hemi- or paraplegia for both sexes, rheumatic diseases for women, and for men diabetes with complications, myocardial infarction, AIDS/HIV, and malignancy.Interpretation — While hip fracture incidence declined for women it was unchanged for men; likewise, 30-day and 1-year mortality rates together with age at first fracture remained unchanged. When these results are compared with the relatively large increase in the prevalence of co-morbidities, it does not seem likely that the increased disease burden is affecting either the incidence or the mortality. 相似文献
109.
目的:观察p53抑制剂pifithrin-α对肝原代细胞增殖及增殖相关蛋白表达的影响。方法:肝原代细胞分别经0、10、20和30μmol/L的pifithrin-α处理1h后,再用10nmol/LEGF诱导30、36和48h,用放射性计数法测定细胞增殖水平。另取肝原代细胞,分3组,对照组常规培养,EGF组用10nmol/L的EGF诱导,EGF+pifithrin-α组用30μmol/Lpifithrin-α和10nmol/LEGF诱导,EGF诱导24、30h后,Westernblot法检测细胞中P53、P21、CyclinD、CyclinE、pErk蛋白的表达水平。结果:pifithrin-α作用后,EGF诱导的细胞增殖水平均降低,且pifithrin-α浓度越大,增殖水平越低(F剂量=54.690,F时间=214.370,F交互=50.450,P<0.001)。与对照组比较,EGF组细胞P53、Cyc-linE蛋白表达水平未发生变化,但P21、CyclinD及pErk表达水平升高(P<0.05),EGF+pifithrin-α组细胞P21、CyclinD及pErk蛋白表达水平较EGF组降低(P<0.05)。结论:P53蛋白可能通过激活MAPK信号通路、上调Cy-clinD表达,从而发挥促进肝原代细胞增殖的作用。 相似文献
110.
Angela Ciaramidaro Cristina Becchio Livia Colle Bruno G. Bara Henrik Walter 《Social cognitive and affective neuroscience》2014,9(7):909-916
Being able to comprehend communicative intentions and to recognize whether such intentions are directed toward us or not is extremely important in social interaction. Two brain systems, the mentalizing and the mirror neuron system, have been proposed to underlie intention recognition. However, little is still known about how the systems cooperate within the process of communicative intention understanding and to what degree they respond to self-directed and other-directed stimuli. To investigate the role of the mentalizing and the mirror neuron system, we used functional magnetic resonance imaging with four types of action sequence: communicative and private intentions as well as other-directed and self-directed intentions. Categorical and functional connectivity analyses showed that both systems contribute to the encoding of communicative intentions and that both systems are significantly stronger activated and more strongly coupled in self-directed communicative actions. 相似文献