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101.
102.
Mulligan KA Fuerer C Ching W Fish M Willert K Nusse R 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(2):370-377
Lipid-modified Wnt/Wingless (Wg) proteins can signal to their target cells in a short- or long-range manner. How these hydrophobic proteins travel through the extracellular environment remains an outstanding question. Here, we report on a Wg binding protein, Secreted Wg-interacting molecule (Swim), that facilitates Wg diffusion through the extracellular matrix. Swim, a putative member of the Lipocalin family of extracellular transport proteins, binds to Wg with nanomolar affinity in a lipid-dependent manner. In quantitative signaling assays, Swim is sufficient to maintain the solubility and activity of purified Wg. In Drosophila, swim RNAi phenotypes resemble wg loss-of-function phenotypes in long-range signaling. We propose that Swim is a cofactor that promotes long-range Wg signaling in vivo by maintaining the solubility of Wg. 相似文献
103.
Volkmer JP Sahoo D Chin RK Ho PL Tang C Kurtova AV Willingham SB Pazhanisamy SK Contreras-Trujillo H Storm TA Lotan Y Beck AH Chung BI Alizadeh AA Godoy G Lerner SP van de Rijn M Shortliffe LD Weissman IL Chan KS 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(6):2078-2083
Current clinical judgment in bladder cancer (BC) relies primarily on pathological stage and grade. We investigated whether a molecular classification of tumor cell differentiation, based on a developmental biology approach, can provide additional prognostic information. Exploiting large preexisting gene-expression databases, we developed a biologically supervised computational model to predict markers that correspond with BC differentiation. To provide mechanistic insight, we assessed relative tumorigenicity and differentiation potential via xenotransplantation. We then correlated the prognostic utility of the identified markers to outcomes within gene expression and formalin-fixed paraffin-embedded (FFPE) tissue datasets. Our data indicate that BC can be subclassified into three subtypes, on the basis of their differentiation states: basal, intermediate, and differentiated, where only the most primitive tumor cell subpopulation within each subtype is capable of generating xenograft tumors and recapitulating downstream populations. We found that keratin 14 (KRT14) marks the most primitive differentiation state that precedes KRT5 and KRT20 expression. Furthermore, KRT14 expression is consistently associated with worse prognosis in both univariate and multivariate analyses. We identify here three distinct BC subtypes on the basis of their differentiation states, each harboring a unique tumor-initiating population. 相似文献
104.
Kushner MG Wall MM Krueger RF Sher KJ Maurer E Thuras P Lee S 《Alcoholism, clinical and experimental research》2012,36(2):325-331
Background: Alcohol dependence is more prevalent among those with any one of several anxiety or depressive (“internalizing”) disorders than among those in the general population. However, because internalizing disorders are highly intercorrelated, it is ambiguous whether alcohol dependence is related to internalizing psychopathology components that are: (i) unique to a particular internalizing disorder (“specific”); versus (ii) shared across a number of internalizing disorders (“general”). To clarify this ambiguity, we employed structural equation and logistic models to decompose the specific versus general components of internalizing psychopathology and then related these components separately to alcohol dependence. Methods: The data were based on face‐to‐face interviews of U.S. community residents collected in the 2001 to 2002 National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; N = 43,093). Results: Both analytic approaches demonstrated that increases in the general internalizing psychopathology load are accompanied by increases in the prevalence of alcohol dependence. Once the general internalizing psychopathology load is accounted for, knowing whether a particular internalizing disorder is present or absent provides little additional information regarding the prevalence of alcohol dependence. Conclusions: The components of internalizing psychopathology that are associated with alcohol dependence are shared and cumulative among common anxiety and depressive disorders. These findings have the potential to influence clinical and scientific conceptualizations of the association between alcohol dependence and internalizing psychopathology. 相似文献
105.
Sung H. Yang Josh Gustafson Matt Gangidine David Stepien Rebecca Schuster Timothy A. Pritts Michael D. Goodman Daniel G. Remick Alex B. Lentsch 《The Journal of surgical research》2013
Background
Mild traumatic brain injury (TBI) is a serious public health concern affecting more than 1.7 million people in the United States annually. Mild TBI is difficult to diagnose and is clinically associated with impaired motor coordination and cognition.Methods
We subjected mice to a mild TBI (mTBI-1 or mTBI-2) induced by a weight drop model. We assessed brain injury histologically and biochemically, the latter by serum neuron-specific enolase and glial fibrillary acidic protein. Systemic and brain inflammation were measured by cytokine array. We determined blood–brain barrier integrity by cerebral vascular leakage of micromolecular and macromolecular fluorescent molecules. We evaluated mice using a rotarod device and novel object recognition to measure motor coordination and cognition, respectively.Results
Mice undergoing mTBI-1 or mTBI-2 had significant deficits in motor coordination and cognition for several days after injury compared with controls. Furthermore, both mTBI-1 and mTBI-2 caused micromolecular leakage in the blood–brain barrier, whereas only mTBI-2 caused macromolecular leakage. Serum neuron-specific enolase and glial fibrillary acidic protein were elevated acutely and corresponded to the degree of injury, but returned to baseline within 24 h. Serum cytokines interleukin-6 and keratinocyte-derived chemokine were significantly increased within 90 min of TBI. Interleukin-6 levels correlated with the degree of injury.Conclusions
The current study provides a reproducible model of mild TBI in mice that exhibits pathologic features of mild TBI in humans. Furthermore, our data suggest that serum cytokines, such as IL-6, may be effective biomarkers for severity of head injury. 相似文献106.
Aims To examine the reciprocal effects between the onset and course of alcohol use disorder (AUD) and normative changes in personality traits of behavioral disinhibition and negative emotionality during the transition between adolescence and young adulthood. Design Longitudinal–epidemiological study assessing AUD and personality at ages 17 and 24 years. Setting Participants were recruited from the community and took part in a day‐long, in‐person assessment. Participants Male (n = 1161) and female (n = 1022) twins participating in the Minnesota Twin Family Study. Measurements The effects of onset (adolescent versus young adult) and course (persistent versus desistent) of AUD on change in personality traits of behavioral disinhibition and negative emotionality from ages 17 to 24 years. Findings Onset and course of AUD moderated personality change from ages 17 to 24 years. Adolescent onset AUD was associated with greater decreases in behavioral disinhibition. Those with an adolescent onset and persistent course failed to exhibit normative declines in negative emotionality. Desistence was associated with a ‘recovery’ towards psychological maturity in young adulthood, while persistence was associated with continued personality dysfunction. Personality traits at age 11 predicted onset and course of AUD, indicating personality differences were not due to active substance abuse. Conclusions Personality differences present prior to initiation of alcohol use increase risk for alcohol use disorder, but the course of alcohol use disorder affects the rate of personality change during emerging adulthood. Examining the reciprocal effects of personality and alcohol use disorder within a developmental context is necessary to improve understanding for theory and intervention. 相似文献
107.
Joanne L Welton Matt P Morgan Salvador Martí Michael D Stone Bernhard Moser Andrew K Sewell Jane Turton Matthias Eberl 《Journal of bone and mineral research》2013,28(3):464-471
Aminobisphosphonates (NBPs) are used widely against excessive bone resorption in osteoporosis and Paget's disease as well as in metastatic bone disease and multiple myeloma. Intravenous NBP administration often causes mild to severe acute‐phase responses (APRs) that may require intervention with analgesics and antipyretics and lead to treatment noncompliance and nonadherence. We here undertook a phase IV safety trial in patients with osteoporosis to investigate the APR of otherwise healthy individuals to first‐time intravenous treatment with the NBP zoledronate. This study provides unique insight into sterile acute inflammatory responses in vivo, in the absence of confounding factors such as infection or cancer. Our data show that both peripheral γδ T cells and monocytes become rapidly activated after treatment with zoledronate, which ultimately determines the clinical severity of the APR. Our study highlights a key role for IFN‐γ in the zoledronate‐induced APR and identifies pretreatment levels of monocytes and central/memory Vγ9/Vδ2 T cells as well as their responsiveness to zoledronate in vitro as predictive risk factors for the occurrence of subclinical and clinical symptoms. These findings have diagnostic and prognostic implications for patients with and without malignancy and are relevant for Vγ9/Vδ2 T‐cell–based immunotherapy approaches. © 2012 American Society for Bone and Mineral Research. © 2013 American Society for Bone and Mineral Research. 相似文献
108.
Melissa E. Murray Kevin F. Bieniek M. Banks Greenberg Mariely DeJesus-Hernandez Nicola J. Rutherford Marka van Blitterswijk Ellis Niemantsverdriet Peter E. Ash Tania F. Gendron Naomi Kouri Matt Baker Ira J. Goodman Leonard Petrucelli Rosa Rademakers Dennis W. Dickson 《Acta neuropathologica》2013,126(4):545-554
The most common cause of familial frontotemporal lobar degeneration with TAR DNA-binding protein-43 pathology (FTLD-TDP) has been found to be an expansion of a hexanucleotide repeat (GGGGCC) in a noncoding region of the gene C9ORF72. Hippocampal sclerosis (HpScl) is a common finding in FTLD-TDP. Our objective was to screen for the presence of C9ORF72 hexanucleotide repeat expansions in a pathologically confirmed cohort of “pure” hippocampal sclerosis cases (n = 33), outside the setting of FTLD-TDP and Alzheimer’s disease (AD). Using a recently described repeat-associated non-ATG (RAN) translation (C9RANT) antibody that was found to be highly specific for c9FTD/ALS, we identified a single “pure” HpScl autopsy case with a repeat expansion in C9ORF72 (c9HpScl). Mutation screening was also performed with repeat-primed polymerase chain reaction and further confirmed with Southern blotting. The c9HpScl patient had a 14-year history of a slowly progressive amnestic syndrome and a clinical diagnosis of probable AD. Neuropsychological testing revealed memory impairment, but no deficits in other cognitive domains. Autopsy showed hippocampal sclerosis with TDP-43 immunoreactive neuronal inclusions relatively limited to limbic lobe structures. Neuritic pathology immunoreactive for p62 was more frequent than TDP-43 in amygdala and hippocampus. Frequent p62-positive neuronal inclusions were present in cerebellar granule neurons as is typical of C9ORF72 mutation carriers. There was no significant FTLD or motor neuron disease. C9RANT was found to be sensitive and specific in this autopsy-confirmed series of HpScl cases. The findings in this patient suggest that the clinical and pathologic spectrum of C9ORF72 repeat expansion is wider than frontotemporal dementia and motor neuron disease, including cases of progressive amnestic dementia with restricted TDP-43 pathology associated with HpScl. 相似文献
109.
Iannuzzi Dorothea Hall Matt Oreskovic Nicolas M. Aryee Emmanuel Broder-Fingert Sarabeth Perrin James M. Kuhlthau Karen A. 《Journal of autism and developmental disorders》2022,52(2):617-622
Journal of Autism and Developmental Disorders - This study examined emergency department (ED) utilization by adolescents and young adults, 12–30 years of age (AYA) with autism... 相似文献
110.