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Paroxysmal Severe Mitral Regurgitation

MAYO CLINIC PROCEEDINGS 2021年第1期96卷 86-91页

作者： Breen, Thomas J. Jain, C. Charles Tan, Nicholas Y. Miranda, William R. Nishimura, Rick A. Mayo Clin Dept Internal Med Rochester MN USA Mayo Clin Dept Cardiovasc Med 200 First St SW Rochester MN 55905 USA

Objective: To investigate the clinical presentation, pathophysiology, and treatment for "paroxysmal severe mitral regurgitation" (MR), which is an underappreciated cause of heart failure with preserved left ventricular ejection fraction. Methods: We retrospectively reviewed cases of transient severe MR that were evaluated at Mayo Clinic in Rochester, Minnesota, between January 1, 2006, and December 31, 2019. Paroxysmal severe MR was defined as the appearance of transient severe MR in patients with mild MR at rest, normal left ventricle (LV) size, left ventricular ejection fraction greater than 40%, and absence of obstructive coronary artery disease. Results: We identified 6 patients (5 women) with a median age of 68 years. There were 3 distinct mechanisms of paroxysmal severe MR, which we labeled types 1, 2, and 3. Type 1 MR was caused by LV dyssynchrony from a rate-dependent left bundle branch block, which led to apical leaflet tenting and incomplete coaptation. Type 2 MR occurred from mitral annular dilatation during maneuvers that increased left-sided volume. Type 3 MR was caused by coronary artery vasospasm with apical leaflet tenting. Treatments varied depending on the underlying cause and included cardiac resynchronization therapy for type 1, surgical valve replacement for type 2, and medical therapy for type 3. Conclusion: Paroxysmal severe MR is a rare cause of heart failure in patients with preserved LV function. We have identified 3 distinct mechanisms that can lead to this dynamic process, with treatments varying based on the underlying cause. (C) 2020 Mayo foundation for Medical Education and Research.

关键词： 2° CAD COPD CRT CRTP Cx f Hf HLD HTN LA LAD LBBB LV LVEf M MR MV MVR PAWP PCI T2DM TTE

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Stable soil phosphorus transformations following long-term litter manipulation in a lowland tropical forest

Soil Advances

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Soil Advances 2024年 1卷

作者： Benjamin L. Turner Aleksandra W. Bielnicka Pil Joo Kim Institute of Agriculture and Life Sciences Gyeongsang National University 501 Jinju-daero Jinju 52828 Republic of Korea Adamed Pharma S.A. ul. Mariana Adamkiewicza Czosnów 05-125 Poland Division of Applied Life Science (BK 21+ Program) Gyeongsang National University 501 Jinju-daero Jinju 52828 Republic of Korea

Productivity in tropical forests is limited by phosphorus (P) availability, but much of the P in tropical soils occurs in stable forms of limited biological availability. Phosphorus availability is therefore maintained in part by recycling from litterfall, which is susceptible to alterations through environmental change. However, the extent to which litterfall influences more stable forms of soil P remains unclear. We quantified the chemical nature of P in soils from a long-term litter manipulation experiment in lowland tropical forest in Panama, in which soils were subject to a decade of litter removal or addition. We used sequential fractionation to separate soil P into operationally defined inorganic and organic pools of contrasting stability. Labile inorganic P extracted in 0.5 M NaHCO 3 increased three-fold with litter addition, but there was no change in labile organic P, nor in moderately labile P pools extracted in 0.1 M NaOH. Surprisingly, residual (unextracted) P and stable organic P extracted in 0.25 M NaOH + 0.05 M EDTA increased strongly with litter addition and declined with litter removal. However, the distribution of P fractions as a proportion of the total P remained relatively constant. These findings show that long-term change in litterfall influences both available and stable forms of soil P in tropical forests, even though the relative distribution of P forms remains largely unchanged. The large pool of stable P in strongly weathered tropical soils has the potential to support greater long-term productivity as forests exploit the modern CO 2 -enriched atmosphere.

关键词： C carbon CO 2 carbon dioxide EDTA ethylenediaminetetraacetic acid f f statistic HCl hydrochloric acid N nitrogen NaHCO 3 sodium bicarbonate NaOH sodium hydroxide p probability P phosphorus P o organic phosphorus P t total phosphorus Sequential fractionation Tropical forests Litter manipulation Stable phosphorus

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A theoretic study of a distance-based regression model

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Science China Mathematics 2019年第5期62卷 979-998页

作者： Jialu Li Wei Zhang Sanguo Zhang Qizhai Li School of Mathematics and Statistics Beijing Institute of Technology Biostatistics and Bioinformatics Branch National Institute of Child Health and Human Development School of Mathematical Sciences University of Chinese Academy of Sciences Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of Sciences LSC NCMIS Academy of Mathematics and Systems Science Chinese Academy of Sciences

The distance-based regression model has many applications in analysis of multivariate response regression in various ?elds, such as ecology, genomics, genetics, human microbiomics, and neuroimaging. It yields a pseudo f test statistic that assesses the relation between the distance(dissimilarity) of the subjects and the predictors of interest. Despite its popularity in recent decades, the statistical properties of the pseudo f test statistic have not been revealed to our knowledge. This study derives the asymptotic properties of the pseudo f test statistic using spectral decomposition under the matrix normal assumption, when the utilized dissimilarity measure is the Euclidean or Mahalanobis distance. The pseudo f test statistic with the Euclidean distance has the same distribution as the quotient of two Chi-squared-type mixtures. The denominator and numerator of the quotient are approximated using a random variable of the form ξχ_d^2+ η, and the approximate error bound is given. The pseudo f test statistic with the Mahalanobis distance follows an f *** simulation studies, the approximated distribution well matched the "exact" distribution obtained by the permutation procedure. The obtained distribution was further validated on H1N1 in?uenza data, aging human brain data, and embryonic imprint data.

关键词： distance-based regression Euclidean pseudo f test statistic Mahalanobis

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fragility Assessment of Pre-Northridge Steel Moment frames Using finite-Length Plastic Hinge Elements and Concentrated Plasticity fracture Elements

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Computer Modeling in Engineering & Sciences 2019年第9期120卷 657-676页

作者： filipe L.A.Ribeiro Andre RBarbosa Luis CNeves National Laboratory of Civil Engineering(LNEC)&CERIS-Civil Engineering Research and Innovation for Sustainability DECivilUniversity of LisbonLisbonPortugal School of Civil and Construction Engineering Oregon State UniversityOregonUSA and University of BristolBristolUK Resilience Engineering Research Group University of NottinghamNottinghamUK.

Although pre-Northridge earthquake steel moment resisting frame buildings have been shown to be susceptible to brittle connection failures,they still represent a large fraction of the existing steel buildings in the United States of *** this study,the performance of the 3-and 9-story Los Angeles pre-Northridge SAC buildings are analyzed considering ductile and brittle beam-column connection failures,and their *** paper contributes to understanding the influence of uncertainty associated with connections brittle fracture on building interstory deformation capacity and its impact on bias and variability of fragility functions and loss *** results show that considering brittle connections leads to significantly l arger d rift demands a nd t o h igher r epair costs,particularly under intense ground *** fragility curve parameters are derived that account for the effect of the uncertainty of the strength and deformation capacity of brittle connections.

关键词： Brittle fracture finite-length p lastic h inge f ragility c urves r epair c ost ratio welded-flange connections

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The effect of slag variability in the attempted manufacture of AYf (alite-ye'elimite-ferrite) cement clinker at both laboratory and pilot scale

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CEMENT 2024年 16卷

作者： Visa Isteri Katja Ohenoja Christiane Rößler Holger Kletti Pekka Tanskanen Mirja Illikainen Theodore Hanein Timo fabritius Process metallurgy Faculty of Technology University of Oulu PO Box 4300 90014 Finland Fibre and Particle Engineering Faculty of Technology University of Oulu PO Box 4300 90014 Finland F.A. Finger Institute for Building Materials Science Bauhaus-University Weimar Coudraystr. 11 99421 Weimar Germany Manatee Consulting Limited Sheffield S3 7XL UK Department of Materials Science and Engineering The University of Sheffield Sheffield S1 3JD UK

The production of AYf (alite-ye'elimite-ferrite) clinker was tested at laboratory and semi-industrial scale using by-products from the metallurgical industry: AOD slag; ladle slag; and fayalitic slag. Alite could be produced with ye'elimite using fluorine originating from AOD (argon oxygen decarburisation) slag as a mineraliser. After a successful laboratory demonstration, the clinker production was scaled to a semi-industrial trial. It was discovered that the reason for the absence of alite formation in a semi-industrial demonstration was that the AOD slag from the specific batch did not perform the designed mineralisation effect for alite formation. This study demonstrates that alite-ye'elimite can be produced at 1260 °C at laboratory scale by using fluorine mineralisation originating from an industrial by-product – in this case, AOD slag. However, the utilisation of by-products for delicate reactions requires detailed determination of the properties of the slag, as the variability from the same source yields different clinker chemistries and mineral phases.

关键词： Calcium sulphoaluminate cement Scale-up Clinkering Waste valorisation Alite Ye'elimite Mineralisation AOD slag Cement oxide notation: C CaO S SiO 2 A Al 2 O 3 f fe 2 O 3 $ SO 3 M MgO T TiO 2

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Porosity tuned NiO nanocrystallites by solution combustion synthesis for the development of a voltammetric sensor for dopamine

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JOURNAL Of POROUS MATERIALS 2019年第5期26卷 1455-1463页

作者： Shimna, Thooneri Thomas, Jasmine Joseph, Teena Thomas, Tony Thomas, Nygil Nirmalagiri Coll Dept Chem Kannur 670701 Kerala India SN Coll Dept Chem Kannur 670007 Kerala India Deva Matha Coll Dept Chem Kottayam 686633 Kerala India

Nickel oxide (NiO) nanocrystallites of porous structure were synthesised by solution combustion method. The influence of f/O ratio on the structural, morphological and electrochemical parameters was investigated. The sample synthesized at f/O ratio 0.4 had a crystallite size of 5 nm. This sample possesses greater surface area and high porosity whereas the sample synthesized at f/O 0.2 was not porous and had lower surface area. Porous NiO was used to modify the carbon paste electrode for the selective detection of dopamine (DA) in the presence of a lot of excess ascorbic acid and uric acid. Sodium dodecyl sulphate (SDS) casting onto the NiO modified electrode improves the performance towards DA. NiO/SDS/MCPE electrode is completely insensitive to ascorbic acid signals below 1.0 x 10(-3) M and enables the accurate quantification of DA in presence of 1000 fold excess of UA (uric acid). The fabricated electrode shows good reproducibility, stability and linear dynamic range of 0.3-300 mu M.

关键词： NiO f O ratio Dopamine Combustion SDS Carbon paste electrode

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Immunoregulatory effects of Tripterygium wilfordii Hook fand its extracts in clinical practice

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frontiers of Medicine 2019年第5期13卷 556-563页

作者： Dan Luo Zhengyun Zuo Hongyan Zhao Yong Tan Cheng Xiao Traditional Chinese Medicine Hospital of Changping District Beijing 102200China Institute of Clinical Medicine China-Japan Friendship HospitalBeijing 100029China Jiangxi University of Traditional Chinese Medicine Nanchang 330004China Experimental Research Center China Academy of Chinese Medical SciencesBeijing 100070China Institute of Basic Research in Clinical Medicine China Academy of Chinese Medical SciencesBeijing 100070China

Tripterygium wilfordii Hook f (TwHf) and its extracts have long been used for the treatment of rheumatoid arthritis, autoimmune diseases, and kidney disease due to their anti-inflammatory, immunoregulatory, and other pharmacological effects. However, the clinical immunoregulatory effects of TwHf and its extracts remain unclear, so we reviewed their effects for use in clinical practice. This review provides a comprehensive summary of the recent literature on the immunoregulatory effects of TwHf and its extracts in clinical studies. TwHf and its extracts affect the proliferation and activation of T and B cells;ratio of T cell subsets;inflammatory response of monocytes, macrophages, and immunoglobulins;and secretion of many cytokines. Together, these effects dictate immune function in a variety of diseases. TwHf and its extracts can be used alone or in combination with existing therapies against many immune disorders through immunomodulation.

关键词： Tripterygium mlfordii Hook f immunoregulation clinical studies

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food risk characterization from exposure to persistent organic pollutants and metals contaminating eels from an Italian lake

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fOOD ADDITIVES AND CONTAMINANTS PART A-CHEMISTRY ANALYSIS CONTROL EXPOSURE & RISK ASSESSMENT 2019年第5期36卷 779-788页

作者： Chiesa, Luca Maria Zanardi, Emanuela Nobile, Maria Panseri, Sara ferretti, Enrica Ghidini, Sergio foschini, Stefano Ianieri, Adriana Arioli, francesco Univ Milan Dept Hlth Anim Sci & Food Safety Milan Italy Univ Parma Dept Food & Drug Parma Italy Ist Zooprofilatt Sperimentale Lombardia & Emilia Brescia Italy UO Vet DG Welf Milan Italy

Monitoring environmental contaminants in edible animal species is important for the assessment of environmental quality and for food safety as well. In this study, the occurrence of 2,3,7,8 dioxins, and furans, dioxin-like polychlorinated biphenyls, six non-dioxin-like polychlorinated biphenyl indicators (ndl-PCBs), seven polybrominated diphenylethers (PBDEs), four polycyclic aromatic hydrocarbons (PAHs) and four metals (As, Hg, Ni, Pb) was evaluated in 90 European eels (Anguilla anguilla) from Lake Garda. The results on eel samples showed a frequent contamination of dl-PCBs, found at concentrations higher than the maximum limit (ML) provided by European Union in 41 % of the eels. Two PBDE congeners (BDE 47 and BDE 99) were detected in almost all the samples. The contamination by PAHs was found negligible;only one sample had a high concentration of benzo[a]pyrene. Concerning metals, Pb showed concentrations higher than the maximum level (ML) in 77% of the samples, while Ni content could be a cause of acute toxicity due to dermatitis. Extreme consumers (95th percentile) are subjected to an actual risk attributable to dioxins, furans, and mainly dl-PCBs and PBDEs. The contamination of Lake Garda eels is therefore a matter of concern and a constant monitoring of the pollution levels of its freshwater is mandatory.

关键词： eel PCDD f PCB PBDE PAH metals risk assessment food safety

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Quantitation of vitamin K1 in serum using online SPE-LC-MS/MS and the challenges of working with vitamin K

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JOURNAL Of CHROMATOGRAPHY B-ANALYTICAL TECHNOLOGIES IN THE BIOMEDICAL AND LIfE SCIENCES 2019年 1117卷 41-48页

作者： Andersen, Ida Boegh Brasen, Claus Lohman Madsen, Jonna Skov Schmedes, Anne Lillebaelt Hosp Dept Clin Biochem & Immunol Vejle Denmark Univ Southern Denmark Dept Reg Hlth Res Odense Denmark Univ Southern Denmark Dept Clin Res Odense Patient Data Explorat Network OPEN Odense Denmark Odense Univ Hosp Odense Denmark

Vitamin K1 (phylloquinone) is one of the vitamin Ks. Several studies have previously investigated the role of vitamin K1 status in respect to disease, but without consistent results. Since vitamin K deficiency has been associated with different disease states it is important to develop a biochemical analysis with sufficient sensitivity and a low limit of quantitation (LOQ). The vitamin Ks are very fat-soluble. This non-polar nature has given rise to several challenges during the method development, because vitamin K1 sticks to materials used during the process and is lost during evaporation. We found that reducing the sample preparation as much as possible offline, instead using online SPE-LC-MS/MS improves recovery and gives satisfactory chromatograms. An Protein BEH C4 column, 300 angstrom (50 x 2.1 mm, 1.7 mu m particle size) was used as trap column and a Phenyl-Hexyl-LC-column, 100 angstrom (100 x 2.1 mm, 2.6 mu m particle size) was used as analytical column. The mobile phases consisted of 30 mu mol/LNH4f in water and 30 mu mol/LNH4f in MeOH. A triple quadrupole tandem mass spectrometer with atmospheric pressure chemical ionization (APCI) ion source, positive ion mode, was used to perform the mass spectrometric measurements. The method is simple, highly sensitive and fast. The method was validated for vitamin K1 with good analytical performance. With a LOQ of 0.05 nmol/L it is to our knowledge the vitamin K1 method with lowest LOQ reported to date in the literature. It can easily be automated and applied in a routine diagnostic laboratory. Blood collection tubes with different additives were tested and showed no difference. Stability of vitamin K1 in serum was tested at different temperatures (-20 degrees C, 4 degrees C and in light and dark at 20 degrees C over a period of 30 days) and showed that vitamin K1 is light sensitive in serum even after only one day.

关键词： K1 phylloquinone LOQ limit of quantitation LC-MS/MS liquid chromatography tandem mass spectrometry ACN acetonitrile NH 4 f ammonium fluoride IPA isopropanol MeOH methanol EtOH ethanol ZnSO 4 zinc sulfate IS internal standard UPLC ultra performance liquid chromatography SPE solid phase extraction APCI atmospheric pressure chemical ionization MRM multiple reaction monitoring SfC-MS/MS supercritical fluid chromatography–tandem mass spectrometry KEQAS vitamin K external quality assurance scheme t R retention time CV coefficient of variation SD standard deviation

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The prevalence rate of periodontal pathogens and its association with oral squamous cell carcinoma

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APPLIED MICROBIOLOGY AND BIOTECHNOLOGY 2019年第3期103卷 1393-1404页

作者： Chang, Chunrong Geng, fengxue Shi, Xiaoting Li, Yuchao Zhang, Xue Zhao, Xida Pan, Yaping China Med Univ Sch Stomatol Dept Periodont 117 Nanjing North St Shenyang 110002 Liaoning Peoples R China China Med Univ Sch Stomatol Dept Oral Biol 117 Nanjing North St Shenyang 110002 Liaoning Peoples R China

Mounting evidence suggests a causal relationship between specific bacterial infections or microbial compositions and the development of certain malignant neoplasms. In this study, we performed research through 16S rRNA amplicon sequencing, qPCR and fluorescence in situ hybridization to certify the relationship between periodontal pathogens and oral squamous cell carcinoma (OSCC). Subgingival plaque, cancer and paracancerous tissues from 6 patients with OSCC were selected for mapping bacterial profiles by 16S rRNA amplicon sequencing. The research showed that periodontal pathogens were enriched in cancer and paracancerous tissues, while the bacterial profiles were similar between the cancer tissues and subgingival plaque. furthermore, the relative abundance of Porphyromonas gingivalis, fusobacterium nucleatum and Streptococcus sanguinis was detected in 61 cancer tissues, paracancerous tissues and subgingival plaque samples and in 30 normal tissues by qPCR. The results revealed that P. gingivalis and f. nucleatum existed at higher levels in cancer tissue than in normal tissues and were correlated with subgingival plaques. P. gingivalis was detected using a special oligonucleotide probe in 60.7% of OSCC tissues, 32.8% of paracancerous tissues and 13.3% of normal tissues. Relevance analysis showed that P. gingivalis infection was positively associated with late clinical staging, low differentiation and lymph node metastasis in patients with OSCC, which was accompanied by deeper periodontal pockets, severe clinical attachment loss and loss of teeth. This study revealed that there might be a close relationship between oral microorganisms, particularly periodontal pathogens, and OSCC, which might enrich the pathogenesis of oral squamous carcinoma.

关键词： P gingivalis f nucleatum OSCC Periodontal pathogen Differentiation Metastasis

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