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Rockfall localization from seismic polarization considering multiple triaxial geophones and frequency bands

Journal of Mountain Science 2020年第7期17卷 1541-1552页

作者： Liang FENG Veronica PAZZI Emanuele INTRIERI Teresa GRACCHI Giovanni GIGLI Grazia TUCCI Department of Earth Sciences University of FlorenceVia G.La Pira 450121FlorenceItaly Department of Civil and Environment Engineering University of FlorenceVia Santa Marta 350139FlorenceItaly

Boulder/rock mass movements generate ground vibrations that can be recorded by geophone ***,there are two methods applied to rockfall trajectory reconstruction or rockfall seismic *** method uses seismic wave arrival times and is achieved by minimizing the differences in signal arrival times between multiple stations by grid map *** other method uses seismic polarization and is achieved by calculating eventsource back azimuths from the seismic polarizations of rockfall *** this study,we proposed the use of an overdetermined matrix for joint localization based on the polarization *** overdetermined matrix considers the contributions of all geophones in the network,and at each geophone is assigned a different weight according to the recorded signal qualities and the reliability of the calibrated back *** method shows a great advantage relative to the case in which only two sensors are ***,we suggested three marker parameters for proper frequency band selection in back azimuth calculations:energy,rectilinearity,and a special permanent frequency band(SPF).We found that the back azimuths calculated with energy and an SPF are generally close to the real back azimuths measured in the field,while the SPF is limited by seismic attenuation due to a long-distance *** localization results of rockfalls were validated by using field camera videos and in situ *** typical cases and 43 artificially released rockfalls are presented in this *** proposed method provides an interesting way to locate rockfall events and track rockfall trajectories and avoids the difficulties of obtaining accurate arrival times,as required by the arrival times method.

关键词： Rockfall Localization Seismic polarization Seismic monitoring Early warning

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Role of gut microbiota-immunity axis in patients undergoing surgery for colorectal cancer:Focus on short and long-term outcomes

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World Journal of Gastroenterology 2020年第20期26卷 2498-2513页

作者： Ilenia Bartolini Matteo Risaliti Maria Novella Ringressi Filippo Melli Giulia Nannini Amedeo Amedei Paolo Muiesan Antonio Taddei Department of Experimental and Clinical Medicine University of FlorenceFlorence 50134Italy

Human body is colonized by a huge amount of microorganisms mostly located in the gastrointestinal *** dynamic communities,the environment and their metabolites constitute the *** data suggests a causal role of a dysbiotic microbiota in several pathologies,such as metabolic and neurological disorders,immunity dysregulations and cancer,especially the well-studied colorectal cancer ***,many were preclinical studies and a complete knowledge of the pathogenetic mechanisms in humans is still *** gut microbiota can exert direct or indirect effects in different phases of colorectal cancer *** example,Fusobacterium nucleatum promotes cancer through cellular proliferation and some strains of Escherichia coli and Bacteroides fragilis produce ***,dysbiosis may also cause a proinflammatory state and the stimulation of a Th17 response with IL-17 and IL-22 secretion that have a pro-oncogenic activity,as demonstrated for Fusobacterium *** has a crucial role in several stages of postoperative course;dysbiosis in fact seems related with surgical site infections and Enterococcus faecalis(and other collagenase-producers microbes)are suggested as a cause of anastomotic ***,unbalanced presence of some species,together with altered immune response may also have a prognostic *** has also a substantial role in effectiveness of chemotherapy,chemoresistance and in the related side *** other words,a complete knowledge of the fine pathological mechanisms of gut microbiota may provide a wide range of new diagnostic tools other than therapeutic targets in the light of tailored medicine.

关键词： Intestinal microbiota Colorectal cancer Chemo-resistance Therapeutic strategies

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Pathogenesis of alcoholic liver disease:Role of oxidative metabolism

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World Journal of Gastroenterology 2014年第47期20卷 17756-17772页

作者： Elisabetta Ceni Tommaso Mello Andrea Galli Gastroenterology Unit Department of Experimental and Clinical Biochemical SciencesUniversity of Florence50139 FlorenceItaly Center of Excellence for Research Transfer and High EducationDENOtheUniversity of Florence50139 FlorenceItaly Fior Gen Foundation 50123 FlorenceItaly

Alcohol consumption is a predominant etiological factor in the pathogenesis of chronic liver diseases, resulting in fatty liver, alcoholic hepatitis, fibrosis/cirrhosis, and hepatocellular carcinoma (HCC). Although the pathogenesis of alcoholic liver disease (ALD) involves complex and still unclear biological processes, the oxidative metabolites of ethanol such as acetaldehyde and reactive oxygen species (ROS) play a preeminent role in the clinical and pathological spectrum of ALD. Ethanol oxidative metabolism influences intracellular signaling pathways and deranges the transcriptional control of several genes, leading to fat accumulation, fibrogenesis and activation of innate and adaptive immunity. Acetaldehyde is known to be toxic to the liver and alters lipid homeostasis, decreasing peroxisome proliferator-activated receptors and increasing sterol regulatory element binding protein activity via an AMP-activated protein kinase (AMPK)-dependent mechanism. AMPK activation by ROS modulates autophagy, which has an important role in removing lipid droplets. Acetaldehyde and aldehydes generated from lipid peroxidation induce collagen synthesis by their ability to form protein adducts that activate transforming-growth-factor-β-dependent and independent profibrogenic pathways in activated hepatic stellate cells (HSCs). Furthermore, activation of innate and adaptive immunity in response to ethanol metabolism plays a key role in the development and progression of ALD. Acetaldehyde alters the intestinal barrier and promote lipopolysaccharide (LPS) translocation by disrupting tight and adherent junctions in human colonic mucosa. Acetaldehyde and LPS induce Kupffer cells to release ROS and proinflammatory cytokines and chemokines that contribute to neutrophils infiltration. In addition, alcohol consumption inhibits natural killer cells that are cytotoxic to HSCs and thus have an important antifibrotic function in the liver. Ethanol metabolism may also interfere with ce

关键词： Alcohol metabolism Acetaldehyde Reactive oxygen species Alcoholic liver disease Protein adducts Hepatic stellate cells Liver fibrosis CYP2E1

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Mechanosensitivity of N-methyl-D-aspartate receptors(NMDAR)is the key through which amyloid beta oligomers activate them

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Neural Regeneration Research 2022年第6期17卷 1263-1264页

作者： Giulia Fani Fabrizio Chiti Department of Experimental and Clinical Biomedical Sciences Section of BiochemistryUniversity of FlorenceFlorenceItaly

Alzheimer’s disease(AD)is one of the major forms of dementia,accounting for 60 to 80%of the cases of dementia,affecting approximately 50 million people worldwide,which is why it has become an object of great interest in both the medical and social fields(Source:Alzheimer’s Association).One of the main histopathological hallmarks of AD is the formation and accumulation of senile plaques in the brain parenchyma,mainly composed by fibrillar aggregates of the amyloidβ(Aβ)*** peptide is generated by the cleavage of the membrane protein named amyloidβprecursor protein,and its secretion in the extracellular space leads to its aggregation into amyloid *** intermediates of this process of aggregation have been identified,and it was found that prefibrillar,soluble oligomeric forms of Aβare more likely to be the pathological species(Benilova et al.,2012).

关键词： amyloid Alzheimer Aβ

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In vitro effects of polyphenols on colorectal cancer cells

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World Journal of Gastrointestinal Oncology 2014年第8期6卷 289-300页

作者： Barbara Pampaloni Gaia Palmini Carmelo Mavilia Roberto Zonefrati Annalisa Tanini Maria Luisa Brand Department of Surgery and Translational Medicine University of Florence Florence 50139 Italy

AIM:To investigate the effects of quercetin and genistein on colon cancer cell proliferation and their estrogen receptorβ(ERβ)***:Colon cancer cells were stably transfected with a mammalian expression vector to overexpress ERβ(HCT8-β8-expressing cells)or a control vector(HCT8-pSV2neo-expressing cells).The proliferation of these cells was examined after treatment with quercetin or genistein(5-100μmol/L),or 10 nmol/L17β-estradiol(17β-E2).Cell viability was examined by acridine orange staining following treatments for 48 or144 *** of quercetin and genistein on ERβtranscriptional transactivation were examined by luciferase activity in HCT8-β8-expressing cells transiently transfected with a pEREtkLUC reporter *** addition,the regulation of ERβtranscription by phytoestrogens and 17β-E2 was examined by quantitative polymerase chain ***:Proliferation of HCT8-β8-expressing cells was not reduced low doses(5μmol/L)of quercetin and genistein,while it was reduced at 25-50μmol/L with an effect similar to 10 nmol/L 17β-*** with doses of phytoestrogens≥75μmol/L completely blocked cell growth and reduced overall cell counts,however no effects at any dose were observed in HCT8-pSV2neoexpressing *** results were supported by viability staining that revealed acridine orange-stained lysosomes with high doses or extended treatment *** and quercetin(50μmol/L)significantly increased ER-responsive luciferase activity similar to 10nmol/L 17β-E2(P<0.05).Furthermore,genistein and quercetin(50μmol/L),as well as 10 nmol/L 17β-E2significantly increased ERβmRNA levels in HCT8-β8-expressing cells(P<0.05).In addition,treatment of HCT8-pSV2neo-expressing cells with 50μmol/L quercetin or 10 nmol/L 17β-E2 significantly increased ERβmRNA levels compared to untreated controls(P<0.05),though the absolute levels were much lower than in HCT8-β8-expressing ***:The antitumorigenic effects of the phytoestrogenic compounds querc

关键词： Estrogen receptor HCT8-β8 cells HCT8pSV2neo Quercetin Genistein

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CT colonography after incomplete colonoscopy in subjects with positive faecal occult blood test

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World Journal of Gastroenterology 2008年第28期14卷 4499-4504页

作者： Lapo Sali Massimo Falchini Andrea Giovanni Bonanomi Guido Castiglione Stefano Ciatto Paola Mantellini Francesco Mungai Ilario Menchi Natale Villari Mario Mascalchi Radiodiagnostic Section Department of Clinical PhysiopathologyUniversity of FlorenceFlorence 50134Italy Centro per lo Studio e la Prevenzione Oncologica (CSPO) Florence 50100Italy Diagnostic Imaging Department Careggi HospitalFlorence 50134Italy

AIM： To report our experience with computed tomography colonography （CTC） systematically performed in subjects with positive faecal occult blood test （FOBT） and an incomplete colonoscopy in the setting of a population-based screening for colorectal cancer （CRC）. METHODS： From April 2006 to April 2007, 43 290 individuals （age range 50-70） who adhered to the regional screening program for the prevention of CRC underwent immunochemical FOBT. FOBT was positive in 1882 subjects （4.3%）. 1463 （77.7%） of these subjects underwent colonoscopy, 903 performed in a single center. Of 903 colonoscopies 65 （7.2%） were incomplete. Forty-two of these subjects underwent CTC. CTC was performed with a 16-MDCT scanner after standard bowel prep （polyethyleneglycole） in both supine and prone position. Subjects whose CTC showed polyps or masses were referred to the endoscopist for repeat colonoscopy under sedation or underwent surgery. Perlesion and per-segment positive predictive values （PPV） were calculated. RESULTS： Twenty-one （50%） of 42 CTCs showed polyps or masses. Fifty-five of these subjects underwent a repeat colonoscopy, whereas 2 subjects underwent surgery for colonic masses of indeterminate nature. Four subjects refused further examinations. CTC correctly identified 2 colonic masses and 20 polyps. PPV for masses or polyps greater than 9 mm was of 87.5%. Per-lesion and per-segment PPV were, respectively, 83.3% and 83.3% for polyps greater or equal to 10 mm, and 77.8% and 85.7% for polyps of 6-9 mm. CONCLUSION： In the context of a screening program for CRC based on FOBT, CTC shows high per-segment and per-lesion PPV for colonic masses and polyps greater than 9 mm. Therefore, CTC has the potential to become a useful technique for evaluation of the non visualized part of the colon after incomplete colonoscopy.

关键词： Computed tomography colonography Virtual colonoscopy Incomplete colonoscopy Positive faecal occult blood test Colorectal cancer screening

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Adipose-derived stem cells:Pathophysiologic implications vs therapeutic potential in systemic sclerosis

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World Journal of Stem Cells 2021年第1期13卷 30-48页

作者： Irene Rosa Eloisa Romano Bianca Saveria Fioretto Marco Matucci-Cerinic Mirko Manetti Department of Experimental and Clinical Medicine Section of Anatomy and HistologyUniversity of FlorenceFlorence 50134Italy Department of Experimental and Clinical Medicine Division of RheumatologyUniversity of FlorenceFlorence 50134Italy

Adipose-derived stem cells(ADSCs)residing in the stromal vascular fraction(SVF)of white adipose tissue are recently emerging as an alternative tool for stem cell-based therapy in systemic sclerosis(SSc),a complex connective tissue disorder affecting the skin and internal organs with fibrotic and vascular *** preclinical and clinical studies have reported promising therapeutic effects of fat grafting and autologous SVF/ADSC-based local treatment for facial and hand cutaneous manifestations of SSc ***,currently available data indicate that ADSCs may represent a double-edged sword in SSc,as they may exhibit a pro-fibrotic and anti-adipogenic phenotype,possibly behaving as an additional pathogenic source of pro-fibrotic myofibroblasts through the adipocyte-to-myofibroblast transition ***,in the perspective of a larger employ of SSc-ADSCs for further therapeutic applications,it is important to definitely unravel whether these cells present a comparable phenotype and similar immunosuppressive,anti-inflammatory,anti-fibrotic and pro-angiogenic properties in respect to healthy *** light of the dual role that ADSCs seem to play in SSc,this review will provide a summary of the most recent insights into the preclinical and clinical studies employing SVF and ADSCs for the treatment of the disease and,at the same time,will focus on the main findings highlighting the possible involvement of these stem cells in SSc-related fibrosis pathogenesis.

关键词： Systemic sclerosis Adipose-derived stromal vascular fraction Adiposederived stem cells Therapeutic approaches Pathogenesis Adipocyte-to-myofibroblast transition

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Metabolomics profile in gastrointestinal cancers:Update and future perspectives

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World Journal of Gastroenterology 2020年第20期26卷 2514-2532页

作者： Giulia Nannini Gaia Meoni Amedeo Amedei Leonardo Tenori Department of Experimental and Clinical Medicine University of FlorenceFlorence 50134Italy Giotto Biotech Srl and CERM(University of Florence)Florence 50019Italy SOD of Interdisciplinary Internal Medicine Azienda Ospedaliera Universitaria CareggiFlorence 50134Italy Consorzio Interuniversitario Risonanze Magnetiche di Metalloproteine Florence 50019Italy

Despite recent progress in diagnosis and therapy,gastrointestinal(GI)cancers remain one of the most important causes of death with a poor prognosis due to late *** tumor markers and detection of occult blood in the stool are the current tests used in the clinic of GI cancers;however,these tests are not useful as diagnostic screening since they have low specificity and low *** that one of the hallmarks of cancer is dysregulated metabolism and metabolomics is an optimal approach to illustrate the metabolic mechanisms that belong to living systems,is now clear that this-omics could open a new way to study *** the last years,nuclear magnetic resonance(NMR)metabolomics has demonstrated to be an optimal approach for diseases’diagnosis nevertheless a few studies focus on the NMR capability to find new biomarkers for early diagnosis of GI *** these reasons in this review,we will give an update on the status of NMR metabolomic studies for the diagnosis and development of GI cancers using biological fluids.

关键词： Metabolomics Nuclear magnetic resonance spectroscopy Pancreatic cancer Gastric cancer Colorectal cancer Biological fluids

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Nuclear receptors and pathogenesis of pancreatic cancer

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World Journal of Gastroenterology 2014年第34期20卷 12062-12081页

作者： Simone Polvani Mirko Tarocchi Sara Tempesti Andrea Galli Department of Experimental and Clinical Biomedical Sciences University of Florence50134 FlorenceItaly

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with a median overall survival time of 5 mo and the five years survival less than 5%, a rate essentially unchanged over the course of the years. A well defined progression model of accumulation of genetic alterations ranging from single point mutations to gross chromosomal abnormalities has been introduced to describe the origin of this disease. However, due to the its subtle nature and concurring events PDAC cure remains elusive. Nuclear receptors (NR) are members of a large superfamily of evolutionarily conserved ligand-regulated DNA-binding transcription factors functionally involved in important cellular functions ranging from regulation of metabolism, to growth and development. Given the nature of their ligands, NR are very tempting drug targets and their pharmacological modulation has been widely exploited for the treatment of metabolic and inflammatory diseases. There are now clear evidences that both classical ligand-activated and orphan NR are involved in the pathogenesis of PDAC from its very early stages; nonetheless many aspects of their role are not fully understood. The purpose of this review is to highlight the striking connections that link peroxisome proliferator activated receptors, retinoic acid receptors, retinoid X receptor, androgen receptor, estrogen receptors and the orphan NR Nur, chicken ovalbumin upstream promoter transcription factor II and the liver receptor homologue-1 receptor to PDAC development, connections that could lead to the identification of novel therapies for this disease.

关键词： Peroxisome proliferator activated receptor Pancreatic intraepithelial neoplasia COUP-TFⅡ Nuclear receptors Orphan nuclear receptor Nuclear receptors 4A2 Nuclear receptors 2F2 Pancreatic cancer Retinoid X receptor Testicular receptor 3

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Evaluation and comparison of short chain fatty acids composition in gut diseases

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World Journal of Gastroenterology 2019年第36期25卷 5543-5558页

作者： Elena Niccolai Simone Baldi Federica Ricci Edda Russo Giulia Nannini Marta Menicatti Giovanni Poli Antonio Taddei Gianluca Bartolucci Antonino Salvatore Calabrò Francesco Claudio Stingo Amedeo Amedei Department of Experimental and Clinical Medicine University of Florence Florence 50134 Italy Department of Biomedical Experimental and Clinical Sciences “Mario Serio” University of Florence Florence 50134 Italy Department of Neurosciences Psychology Drug Research and Child Health Section of Pharmaceutical and Nutraceutical Sciences University of Florence Florence 50134 Italy Department of Statistics Computer Science Applications “G.Parenti” Florence 50134 Italy Department of Biomedicine Azienda Ospedaliera Universitaria Careggi Florence 50134 Italy

BACKGROUND An altered (dysbiosis) and unhealthy status of the gut microbiota is usually responsible for a reduction of short chain fatty acids (SCFAs) concentration. SCFAs obtained from the carbohydrate fermentation processes are crucial in maintaining gut homeostasis and their determination in stool samples could provide a faster, reliable and cheaper method to highlight the presence of an intestinal dysbiosis and a biomarker for various gut diseases. We hypothesize that different intestinal diseases, such as celiac disease (CD), adenomatous polyposis (AP) and colorectal cancer (CRC) could display a particular fecal SCFAs’ signature. AIM To compare the fecal SCFAs’ profiles of CD, AP, CRC patients and healthy controls, using the same analytical method. METHODS In this cross-sectional study, we defined and compared the SCFAs’ concentration in fecal samples of 9 AP, 16 CD, 19 CRC patients and 16 healthy controls (HC). The SCFAs’ analysis were performed using a gas-chromatography coupled with mass spectrometry method. Data analysis was carried out using Wilcoxon ranksum test to assess pairwise differences of SCFAs’ profiles, partial least squaresdiscriminate analysis (PLS-DA) to determine the status membership based on distinct SCFAs’ profiles, and Dirichlet regression to determine factors influencing concentration levels of SCFAs. RESULTS We have not observed any difference in the SCFAs’ amount and composition between CD and healthy control. On the contrary, the total amount of SCFAs was significantly lower in CRC patients compared to HC (P = 0.044) and CD (P = 0.005). Moreover, the SCFAs’ percentage composition was different in CRC and AP compared to HC. In detail, HC displayed higher percentage of acetic acid (P value = 1.3 × 10-6) and a lower amount of butyric (P value = 0.02192), isobutyric (P value = 7.4 × 10-5), isovaleric (P value = 0.00012) and valeric (P value = 0.00014) acids compared to CRC patients. AP showed a lower abundance of acetic acid (P value = 0.

关键词： Short chain fatty acids Microbiota Colorectal cancer Adenoma Celiac disease

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