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91.
92.
C Ferrarese P Mascarucci C Zoia R Cavarretta M Frigo B Begni F Sarinella L Frattola M G De Simoni 《Journal of cerebral blood flow and metabolism》1999,19(9):1004-1009
Cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha can play pathogenetic or protective roles in stroke. They are increased in the brain after experimental ischemia and in the CSF of patients with stroke. However, their presence in the periphery is still controversial. To determine the source and time-course of cytokines in blood of stroke patients, IL-6 and TNF-alpha release from blood cells and serum levels were determined in 40 patients on days 1 through 2, 4, 10, 30, and 90 after stroke. Twenty healthy age-matched volunteers were used as controls. IL-6 and TNF-alpha release from stimulated blood cells was increased in stroke patients, compared to controls. A peak response (+224%) was observed at day 4 for IL-6, while TNF-alpha release was largely and significantly increased (about three-fold compared to controls) from day 1 to 2 until day 90 after stroke. The increase in IL-6 release was significantly higher in ischemic, compared to hemorrhagic strokes, at days 1 and 4. Circulating IL-6 was increased at each time point. The ischemic processes in the CNS induces a long-lasting activation of IL-6 and TNF-alpha production in peripheral blood cells, which are a major source of serum cytokines after stroke. 相似文献
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94.
Miriam Duci Anna Chiara Frigo Silvia Visentin Giovanna Verlato Piergiorgio Gamba Francesco Fascetti-Leon 《Journal of pediatric surgery》2019,54(10):2099-2102
Background/purposeAntenatal factors play an important role in NEC. This study aimed to identify antenatal risk factors associated with the development of NEC, the role of the placental alterations, and the presence of prenatal signs predisposing to a severe NEC.Materials/methodsData of NEC patients including antenatal findings [preeclampsia, diabetes, cholestasis, abnormal antenatal umbilical artery flow (AAUF), clinical chorioamnionitis (CC), and histology of placentas] were compared to unaffected cases between 2002 and 2016 in a single center. Unaffected infants were matched for gestational age. Newborns with cardiovascular diseases were excluded. Bivariate and multivariate analyses were performed.ResultsWe identified 136 cases and 134 controls. The group of mothers of NEC-neonates had a higher prevalence of preeclampsia, CC, and AAUF. Histology of Placentas from 123/136 cases and 126/133 unaffected newborns was available. Chorioamnionitis was significantly more present in NEC cases vs controls. There weren't differences in vascular anomalies and necrotic alterations. Multivariate analysis identified AAUF, CC and histological chorioamnionitis (HC) as predictors of NEC. Bivariate tests show that preeclampsia and HC occurred more often in severe cases of NEC.ConclusionThis study suggests that AAUF, CC, and HC can independently predict the risk of NEC. Preeclampsia and HC seem associated to more severe cases.Level of evidenceIIIA. 相似文献
95.
Diego?CecchinEmail authorView authors OrcID profile Henryk?Barthel Davide?Poggiali Annachiara?Cagnin Solveig?Tiepolt Pietro?Zucchetta Paolo?Turco Paolo?Gallo Anna?Chiara?Frigo Osama?Sabri Franco?Bui 《European journal of nuclear medicine and molecular imaging》2017,44(12):2060-2072
Purpose
In the initial evaluation of patients with suspected dementia and Alzheimer’s disease, there is no consensus on how to perform semiquantification of amyloid in such a way that it: (1) facilitates visual qualitative interpretation, (2) takes the kinetic behaviour of the tracer into consideration particularly with regard to at least partially correcting for blood flow dependence, (3) analyses the amyloid load based on accurate parcellation of cortical and subcortical areas, (4) includes partial volume effect correction (PVEC), (5) includes MRI-derived topographical indexes, (6) enables application to PET/MRI images and PET/CT images with separately acquired MR images, and (7) allows automation.Methods
A method with all of these characteristics was retrospectively tested in 86 subjects who underwent amyloid (18F-florbetaben) PET/MRI in a clinical setting (using images acquired 90–110 min after injection, 53 were classified visually as amyloid-negative and 33 as amyloid-positive). Early images after tracer administration were acquired between 0 and 10 min after injection, and later images were acquired between 90 and 110 min after injection. PVEC of the PET data was carried out using the geometric transfer matrix method. Parametric images and some regional output parameters, including two innovative “dual time-point” indexes, were obtained.Results
Subjects classified visually as amyloid-positive showed a sparse tracer uptake in the primary sensory, motor and visual areas in accordance with the isocortical stage of the topographic distribution of the amyloid plaque (Braak stages V/VI). In patients classified visually as amyloid-negative, the method revealed detectable levels of tracer uptake in the basal portions of the frontal and temporal lobes, areas that are known to be sites of early deposition of amyloid plaques that probably represented early accumulation (Braak stage A) that is typical of normal ageing. There was a strong correlation between age and the indexes of the new dual time-point amyloid imaging method in amyloid-negative patients.Conclusions
The method can be considered a valuable tool in both routine clinical practice and in the research setting as it will standardize data regarding amyloid deposition. It could potentially also be used to identify early amyloid plaque deposition in younger subjects in whom treatment could theoretically be more effective.96.
Frigo DE Howe MK Wittmann BM Brunner AM Cushman I Wang Q Brown M Means AR McDonnell DP 《Cancer research》2011,71(2):528-537
While patients with advanced prostate cancer initially respond favorably to androgen ablation therapy, most experience a relapse of the disease within 1-2 years. Although hormone-refractory disease is unresponsive to androgen-deprivation, androgen receptor (AR)-regulated signaling pathways remain active and are necessary for cancer progression. Thus, both AR itself and the processes downstream of the receptor remain viable targets for therapeutic intervention. Microarray analysis of multiple clinical cohorts showed that the serine/threonine kinase Ca2+/calmodulin-dependent protein kinase kinase β (CaMKKβ) is both highly expressed in the prostate and further elevated in prostate cancers. Using cellular models of prostate cancer, we have determined that androgens (a) directly increase the expression of a CaMKKβ splice variant and (b) increase functional CaMKKβ protein levels as determined by the phosphorylation of both CaMKI and AMP-activated protein kinase (AMPK), two of CaMKKβ's primary substrates. Importantly, inhibition of the CaMKKβ-AMPK, but not CaMKI, signaling axis in prostate cancer cells by pharmacological inhibitors or siRNA-mediated knockdown blocks androgen-mediated migration and invasion. Conversely, overexpression of CaMKKβ alone leads to both increased AMPK phosphorylation and cell migration. Given the key roles of CaMKKβ and AMPK in the biology of prostate cancer cells, we propose that these enzymes are potential therapeutic targets in prostate cancer. 相似文献
97.
Chiesa S Morbelli S Morando S Massollo M Marini C Bertoni A Frassoni F Bartolomé ST Sambuceti G Traggiai E Uccelli A 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(42):17384-17389
Dendritic cells (DC) are highly specialized antigen-presenting cells characterized by the ability to prime T-cell responses. Mesenchymal stem cells (MSC) are adult stromal progenitor cells displaying immunomodulatory activities including inhibition of DC maturation in vitro. However, the specific impact of MSC on DC functions, upon in vivo administration, has never been elucidated. Here we show that murine MSC impair Toll-like receptor-4 induced activation of DC resulting in the inhibition of cytokines secretion, down-regulation of molecules involved in the migration to the lymph nodes, antigen presentation to CD4(+) T cells, and cross-presentation to CD8(+) T cells. These effects are associated with the inhibition of phosphorylation of intracellular mitogen-activated protein kinases. Intravenous administration of MSC decreased the number of CCR7 and CD49dβ1 expressing CFSE-labeled DC in the draining lymph nodes and hindered local antigen priming of DO11.10 ovalbumin-specific CD4(+) T cells. Upon labeling of DC with technetium-99m hexamethylpropylene amine oxime to follow their in vivo biodistribution, we demonstrated that intravenous injection of MSC blocks, almost instantaneously, the migration of subcutaneously administered ovalbumin-pulsed DC to the draining lymph nodes. These findings indicate that MSC significantly affect DC ability to prime T cells in vivo because of their inability to home to the draining lymph nodes and further confirm MSC potentiality as therapy for immune-mediated diseases. 相似文献
98.
Flavio Nobili MD Claudio Campus PhysD Dario Arnaldi MD Fabrizio De Carli PsyD Gaia Cabassi PhysD Andrea Brugnolo PsyD Barbara Dessi PsyD Silvia Morbelli MD Gianmario Sambuceti MD Giovanni Abbruzzese MD Guido Rodriguez MD 《Movement disorders》2010,25(1):35-43
To unveil cognitive‐nigrostriatal correlations in Parkinson's disease (PD), 30 de novo, drug‐naïve PD patients and 15 patients with essential tremor (Controls, CTR) underwent a neuropsychological (NPS) battery and brain SPECT with [I‐123]Ioflupane, as a biomarker of nigrostriatal function. Automatic extraction of uptake at caudate and putamen level was conducted through the BasGan software, also allowing partial volume effect correction. Because of the multicollinearity among neuropsychological tests and among SPECT variables, factor analysis was applied to 16 neuropsychological scores; moreover, the four SPECT variables were merged into a mean SPECT value (mSPECT). Factor analysis identified four NPS factors: a dys‐executive (NPS‐EX), a visuospatial (NPS‐VS), a verbal memory (NPS‐VM), and a “mixed” (NPD‐MIX) factor. In PD group, there were inverse correlations between UPDRS‐III score and both NPS‐VS (P < 0.01) and mSPECT (P < 0.05), and a direct correlation between mSPECT and NPS‐EX (P < 0.05). Post hoc analysis showed a direct correlation between NPS‐EX and caudate uptake in both hemispheres (P < 0.05). Moreover, inverse correlations were found between UPDRS‐III and, respectively, putamen uptake in the less affected hemisphere (P < 0.01), and putamen and caudate uptake in the more affected hemisphere (P < 0.05). In CTR, no correlation was found between mSPECT and either NPS or GDS values. Nigro‐caudate function affects executive capabilities in PD but not in CTR, which appears to be unrelated to the disease motor severity at its onset. Instead, PD motor severity is related to nigro‐putaminal impairment and visuospatial dysfunction. The role of these data as predictive features of cognitive decline and eventually dementia remains to be established in longitudinal studies. © 2010 Movement Disorder Society 相似文献
99.
Mozzati M Monfrin SB Pedretti G Schierano G Bassi F 《The International journal of oral & maxillofacial implants》2008,23(2):308-314
PURPOSE: To evaluate the success rate of immediately loaded conventional implants placed in the premaxilla in association with 2 zygomatic implants. MATERIALS AND METHODS: All patients included had worn complete maxillary dentures for at least 2 years. They were required to have no severe systemic pathologies and could not be on any drugs. They could not have any oral infection, uncontrolled periodontal disease, sinusitis, parafunctional signs, alteration of the occlusal plane, or smoking habits. They had to be good candidates for the insertion of 4 or 5 traditional implants in the premaxilla and 2 zygomatic implants without guided bone regeneration. Primary stability had to be achieved. Impressions for prosthetic rehabilitation were made during first-stage surgery. Temporary fixed cross-arch prostheses were inserted 12 to 24 hours after surgery. Permanent cross-arch screw-retained prostheses were placed after 6 months. RESULTS: Seven patients met all the inclusion criteria and were enrolled in the study (Caucasian, 4 males and 3 females, mean age 56.8 years). In total, 14 zygomatic and 34 conventional implants were placed. The survival rate for zygomatic and conventional implants and fixed prostheses was 100% after 24 months of functional loading. CONCLUSION: The preliminary results are encouraging, but the long-term clinical prognosis remains to be determined. 相似文献
100.