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991.
Goldstein LE Fisher AM Tagge CA Zhang XL Velisek L Sullivan JA Upreti C Kracht JM Ericsson M Wojnarowicz MW Goletiani CJ Maglakelidze GM Casey N Moncaster JA Minaeva O Moir RD Nowinski CJ Stern RA Cantu RC Geiling J Blusztajn JK Wolozin BL Ikezu T Stein TD Budson AE Kowall NW Chargin D Sharon A Saman S Hall GF Moss WC Cleveland RO Tanzi RE Stanton PK McKee AC 《Science translational medicine》2012,4(134):134ra60
Blast exposure is associated with traumatic brain injury (TBI), neuropsychiatric symptoms, and long-term cognitive disability. We examined a case series of postmortem brains from U.S. military veterans exposed to blast and/or concussive injury. We found evidence of chronic traumatic encephalopathy (CTE), a tau protein-linked neurodegenerative disease, that was similar to the CTE neuropathology observed in young amateur American football players and a professional wrestler with histories of concussive injuries. We developed a blast neurotrauma mouse model that recapitulated CTE-linked neuropathology in wild-type C57BL/6 mice 2 weeks after exposure to a single blast. Blast-exposed mice demonstrated phosphorylated tauopathy, myelinated axonopathy, microvasculopathy, chronic neuroinflammation, and neurodegeneration in the absence of macroscopic tissue damage or hemorrhage. Blast exposure induced persistent hippocampal-dependent learning and memory deficits that persisted for at least 1 month and correlated with impaired axonal conduction and defective activity-dependent long-term potentiation of synaptic transmission. Intracerebral pressure recordings demonstrated that shock waves traversed the mouse brain with minimal change and without thoracic contributions. Kinematic analysis revealed blast-induced head oscillation at accelerations sufficient to cause brain injury. Head immobilization during blast exposure prevented blast-induced learning and memory deficits. The contribution of blast wind to injurious head acceleration may be a primary injury mechanism leading to blast-related TBI and CTE. These results identify common pathogenic determinants leading to CTE in blast-exposed military veterans and head-injured athletes and additionally provide mechanistic evidence linking blast exposure to persistent impairments in neurophysiological function, learning, and memory. 相似文献
992.
Salas V Pastor FJ Calvo E Alvarez E Sutton DA Mayayo E Fothergill AW Rinaldi MG Guarro J 《Antimicrobial agents and chemotherapy》2012,56(5):2246-2250
The in vitro susceptibility of 17 strains of Mucor circinelloides to amphotericin B and posaconazole was ascertained by using broth microdilution and disk diffusion methods and by determining the minimal fungicidal concentration (MFC). We evaluated the efficacy of posaconazole at 40 mg/kg of body weight/day and amphotericin B at 0.8 mg/kg/day in a neutropenic murine model of disseminated infection by M. circinelloides by using 6 different strains tested previously in vitro. In general, most of the posaconazole MICs were within the range of susceptibility or intermediate susceptibility, while the small inhibition zone diameters (IZDs) were indicative of nonsusceptibility for all isolates tested. The MFCs were ≥ 3 dilutions higher than the corresponding MICs. In contrast, amphotericin B showed good activity against all of the strains tested regardless of the method used. The in vivo studies demonstrated that amphotericin B was effective in prolonging survival and reducing the fungal load. Posaconazole showed poor in vivo efficacy with no correlation with the MIC values. The results suggested that posaconazole should be used with caution in the treatment of infections caused by Mucor circinelloides or by strains of Mucor not identified to the species level. 相似文献
993.
994.
Jakobsen L Cattoir V Jensen KS Hammerum AM Nordmann P Frimodt-Møller N 《The Journal of antimicrobial chemotherapy》2012,67(10):2438-2444
995.
Little is known about prenatal breastfeeding confidence, although such knowledge is necessary for developing the content of counseling and tailoring it for individuals. The purpose of this study was to describe women's prenatal breastfeeding confidence and how their sociodemographic characteristics, breastfeeding knowledge, and attitudes relate to it. The electronic confidence scale was used in data collection, and 123 Finnish women filled in the questionnaire. The mean confidence score was 83.88 when the maximum possible score was 120. Confidence scores varied when parity, breastfeeding knowledge, and attitudes were involved. Variables regarding breastfeeding as difficult, regarding breastfeeding as exhausting, and parity explained 38.1% of the variation of the breastfeeding confidence scores. Pregnant women need information about managing potential breastfeeding problems and the physiology of breastfeeding. Interventions designed to promote breastfeeding confidence need to be focused on primiparas and women with a lack of breastfeeding knowledge. 相似文献
996.
997.
Although chronic illness is likely to affect the well-being of patients' children, no assessment tools are currently available to measure this impact of parental illness. We therefore developed such an instrument based on interviews with children of patients with Parkinson's disease (PD). This questionnaire and other measures of psychological well-being were completed by 89 children, aged 12-48, years of patients with PD. Factor analysis revealed six domains with 38 questions. These six domains of the 'Parental Illness Impact Scale (Parkinson's disease)' or PIIS (PD) had satisfactory internal consistency and validity. Its six sub-scales correlated significantly and differentially with corresponding measures, including the Quality of Life in Epilepsy Inventory for Adolescents (QOLIE-AD-48; r = -0.2 to 0.85), the Beck Depression Inventory (r = -0.07 to -0.40) or Birleson Depression Self-Rating Scale (r = 0.04 to -0.62), and the Rosenberg Self-Esteem Scale (r = -0.01 to 0.33) as well as age (r = -0.37 to 0.28) and parent's disease duration (r = -0.31 to 0.34). The PIIS is the first instrument to assess the impact of parental illness on children. Its psychometric properties should be tested further in larger samples, including children of patients with other chronic disorders such as multiple sclerosis or chronic heart disease. 相似文献
998.
Marianna S. Thomas David Newman Olof Dahlqvist Leinhard Bahman Kasmai Richard Greenwood Paul N. Malcolm Anette Karlsson Johannes Rosander Magnus Borga Andoni P. Toms 《European radiology》2014,24(9):2279-2291
Purpose
To measure the test-retest reproducibility of an automated system for quantifying whole body and compartmental muscle volumes using wide bore 3 T MRI.Materials and methods
Thirty volunteers stratified by body mass index underwent whole body 3 T MRI, two-point Dixon sequences, on two separate occasions. Water-fat separation was performed, with automated segmentation of whole body, torso, upper and lower leg volumes, and manually segmented lower leg muscle volumes.Results
Mean automated total body muscle volume was 19·32 L (SD9·1) and 19·28 L (SD9·12) for first and second acquisitions (Intraclass correlation coefficient (ICC)?=?1·0, 95 % level of agreement -0·32–0·2 L). ICC for all automated test-retest muscle volumes were almost perfect (0·99–1·0) with 95 % levels of agreement 1.8–6.6 % of mean volume. Automated muscle volume measurements correlate closely with manual quantification (right lower leg: manual 1·68 L (2SD0·6) compared to automated 1·64 L (2SD 0·6), left lower leg: manual 1·69 L (2SD 0·64) compared to automated 1·63 L (SD0·61), correlation coefficients for automated and manual segmentation were 0·94–0·96).Conclusion
Fully automated whole body and compartmental muscle volume quantification can be achieved rapidly on a 3 T wide bore system with very low margins of error, excellent test-retest reliability and excellent correlation to manual segmentation in the lower leg.Key Points
? Sarcopaenia is an important reversible complication of a number of diseases. ? Manual quantification of muscle volume is time-consuming and expensive. ? Muscles can be imaged using in and out of phase MRI. ? Automated atlas-based segmentation can identify muscle groups. ? Automated muscle volume segmentation is reproducible and can replace manual measurements. 相似文献999.
High-risk HPV E6 and E7 oncoproteins cooperate to subvert critical host cell cycle checkpoint control mechanisms in order to promote viral genome replication. This results not only in aberrant proliferation but also in host cellular changes that can promote genomic instability. The HPV-16 E7 oncoprotein was found to induce centrosome abnormalities thereby disrupting mitotic fidelity and increasing the risk for chromosome missegregation and aneuploidy. In addition, expression of the high-risk HPV E7 oncoprotein stimulates DNA replication stress as a potential source of DNA breakage and structural chromosomal instability. Proliferation of genomically unstable cells is sustained by several mechanisms including the accelerated degradation of claspin by HPV-16 E7 and the degradation of p53 by the high-risk HPV E6 oncoprotein. These results highlight the oncogenic potential of aberrant proliferation and opens new avenues for prevention of malignant progression, not only in HPV-associated cervical cancer but also in non-virally associated malignancies with disrupted cell cycle checkpoint control mechanisms. 相似文献
1000.
Grekova SP Aprahamian M Daeffler L Leuchs B Angelova A Giese T Galabov A Heller A Giese NA Rommelaere J Raykov Z 《Cancer biology & therapy》2011,12(10):888-895
Oncolytic viruses with their capacity to specifically replicate in and kill tumor cells emerged as a novel class of cancer therapeutics. Rat oncolytic parvovirus (H-1PV) was used to treat different types of cancer in preclinical settings and was lately successfully combined with standard gemcitabine chemotherapy in treating pancreatic ductal adenocarcinoma (PDAC) in rats. Our previous work showed that the immune system and particularly the release of interferon-gamma (IFNγ) seem to mediate the anticancer effect of H-1PV in that model. Therefore, we reasoned that the therapeutic properties of H-1PV can be boosted with IFNγ for the treatment of late incurable stages of PDAC like peritoneal carcinomatosis. Rats bearing established orthotopic pancreatic carcinomas with peritoneal metastases were treated with a single intratumoral (i.t.) or intraperitoneal (i.p.) injection of 5x108 plaque forming units of H-1PV with or without concomitant IFNγ application. Intratumoral injection proved to be more effective than the intraperitoneal route in controlling the growth of both the primary pancreatic tumors and peritoneal carcinomatosis, accompanied by migration of virus from primary to metastatic deposits. Concomitant i.p. treatment of H-1PV with recIFNγ resulted in improved therapeutic effect yielding an extended animal survival, compared with i.p. treatment with H-1PV alone. IFNγ application enhanced the H-1PV-induced peritoneal macrophage and splenocyte responses against tumor cells while causing a significant reduction in the titers of H1-PV-neutralising antibodies in ascitic fluid. Thus, IFNγ co-application together with H-1PV might be considered as a novel therapeutic option to improve the survival of PDAC patients with peritoneal carcinomatosis. 相似文献