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Evidence for the involvement of infectious agents in the pathogenesis of Crohn's disease

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World Journal of Gastroenterology 2008年第6期14卷 845-852页

作者： Gert De Hertogh jeroen Aerssens Karen P Geboes Karel Geboes Karel Geboes Department of Pathology University Hospitals KULeuven Minderbroedersstraat 12 Leuven 3000 Belgium Tibotec bvba Generaal De Wittelaan L 11B 3 Mechelen 2800 Belgium Department of Gastroenterology University Hospitals KULeuven Herestraat 49 Leuven 3000 Belgium

Many advances have been made in the understanding of Crohn’s disease (CD) pathogenesis during the last decade. CD is currently seen as a predominantly T-lym-phocyte-driven disease characterized by the presence of a complex cocktail of interacting cytokines, chemokines and other mediators produced by a variety of cell types. Prevailing theories of CD pathogenesis suggest that patients’ T-lymphocytes are inappropriately activated in the setting of an immune imbalance, which is itself caused by an unfortunate confluence of genetic and en- vironmental factors. The T-cell response then leads to the chronic inflammation characteristic for the disease. Various environmental factors may play a role in the development of CD, but microbes are most consistently implied. This theory is based on epidemiological, clinico- pathological, genetic and experimental evidence. Despite the abundance of arguments for the implication of bac-teria in the aetiopathogenesis of CD, the precise role of bacteria in this disease still remains elusive. Three not necessarily mutually exclusive theories have been pro- posed: (1) an unidentified persistent pathogen; (2) an abnormally permeable mucosal barrier leading to exces-sive bacterial translocation; and (3) a breakdown in the balance between putative "protective" versus "harmful" intestinal bacteria ("dysbiosis"). At present, one cannot exclude with certainty any of these three proposed hy-potheses; they may all apply to CD to a certain extent.

关键词： Crohn's disease Etiology Microbiology

Diagnosis and management of splanchnic ischemia

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World Journal of Gastroenterology 2008年第48期14卷 7309-7320页

作者： jeroen J Kolkman Marloes Bargeman Ad B Huisman Robert H Geelkerken Department of Gastro-enterology Medisch Spectrum Twente Department of Interventional Radiology Medisch Spectrum Twente Department of Vascular Surgery Medisch Spectrum Twente

Splanchnic or gastrointestinal ischemia is rare and randomized studies are absent. This review focuses on new developments in clinical presentation, diagnostic approaches, and treatments. Splanchnic ischemia can be caused by occlusions of arteries or veins and by physiological vasoconstriction during low-flow states. The prevalence of significant splanchnic arterial stenoses is high, but it remains mostly asymptomatic due to abundant collateral circulation. This is known as chronic splanchnic disease (CSD). Chronic splanchnic syndrome (CSS) occurs when ischemic symptoms develop. Ischemic symptoms are characterized by postprandial pain, fear of eating and weight loss. CSS is diagnosed by a test for actual ischemia. Recently, gastro-intestinal tonometry has been validated as a diagnostic test to detect splanchnic ischemia and to guide treatment. In single- vessel CSD, the complication rate is very low, but some patients have ischemic complaints, and can be treated successfully. In multi-vessel stenoses, the complication rate is considerable, while most have CSS and treatment should be strongly considered. CT and MR-based angiographic reconstruction techniques have emerged as alternatives for digital subtraction angiography for imaging of splanchnic vessels. Duplex ultrasound is still the first choice for screening purposes. The strengths and weaknesses of each modality will be discussed. CSS may be treated by minimally invasive endoscopic treatment of the celiac axis compression syndrome, endovascular antegrade stenting, or laparotomy-assisted retrograde endovascular recanalization and *** treatment plan is highly individualized and is mainly based on precise vessel anatomy, body weight, co- morbidity and severity of ischemia.

关键词： Splanchnic ischemia Mesenteric ischemia Tonometry Blood flow Chronic splanchnic syndrome Chronic splanchnic disease Chronic mesenteric isch-emia Celiac artery compression syndrome Ischemiccolitis

A great thermal divergence in the mantle beginning 2.5 Ga:Geochemical constraints from greenstone basalts and komatiites

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Geoscience Frontiers 2016年第4期7卷 543-553页

作者： Kent C.Condie Richard C.Aster jeroen van Hunen Department of Earth and Environmental Science New Mexico Tech Geosciences Department Colorado State University Department of Earth Sciences University of Durham

Greenstone basalts and komatiites provide a means to track both mantle composition and magma generation temperature with time. Four types of mantle are characterized from incompatible element distributions in basalts and komatiites： depleted, hydrated, enriched and mantle from which komatiites are derived. Our most important observation is the recognition for the first time of what we refer to as a Great Thermal Divergence within the mantle beginning near the end of the Archean, which we ascribe to thermal and convective evolution. Prior to 2.5 Ga, depleted and enriched mantle have indistinguishable thermal histories, whereas at 2.5-2.0 Ga a divergence in mantle magma generation temperature begins between these two types of mantle. Major and incompatible element distributions and calculated magma generation temperatures suggest that Archean enriched mantle did not come from mantle plumes, but was part of an undifferentiated or well-mixed mantle similar in composition to calculated primitive mantle. During this time, however, high-temperature mantle plumes from dominantly depleted sources gave rise to komatiites and associated basalts. Recycling of oceanic crust into the deep mantle after the Archean may have contributed to enrichment ofTi, A1, Ca and Na in basalts derived from enriched mantle sources. After 2.5 Ga, increases in Mg# in basalts from depleted mantle and decreases in Fe and Mn reflect some combination of growing depletion and cooling of depleted mantle with time. A delay in cooling of depleted mantle until after the Archean probably reflects a combination of greater radiogenic heat sources in the Archean mantle and the propagation of plate tectonics after 3 Ga.

关键词： Archean greenstones Mantle thermal evolution Basalts Mantle geochemistry Komatiites

An OT Analysis of Nasal-obstruent Clusters in English

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外国语 2013年第6期36卷 2-17页

作者： ZHENG Jizheng jeroen van de Weijer Shanghai Customs College Shanghai 201204 Shanghai International Studies University Shanghai 200083 China

This paper argues in favor of an Optimality Theory(OT)constraint hierarchy governing the phonotactics of nasal+obstruent clusters in *** paper shows that in careful speech English has a strong tendency favoring voiceless obstruents after nasals both in medial and coda positions,and retains a contrast between voiced and voiceless obstruents,as supported by statistical *** the paper proposes that,in English,the Optimality constraint IDENT-IO(ObsVce)dominates**** also show that in English voiced coronal stops are retained post-nasally,whereas voiced peripheral(labial and velar)stops are deleted(or,rather,not permitted).To explain this phenomenon,the paper proposes that the markedness constraint VOICED-CODA ranks between MAX-COR and MAX-PER,and the constraints IDENT-IO(ObsVce)and*VOICED-CODA work in tandem to result in the deletion of peripheral voiced *** shows that the same constraint hierarchy also applies to nasal+non-stop obstruent clusters,*** with fricatives and affricates,both medially and in final ***,It is pointed out that as language is changing,this is reflected in a changing constraint hierarchy as ****VOICEDCODA and*NO become higher ranked,this would cause either devoicing or deletion of voiced obstruents in the coda,or it would cause obstruents after nasals to become *** processes are found in faster,informal speech styles and may reflect change in progress.

关键词：英语学习阅读知识学习方法阅读材料

Delivery of Micro RNAs by plant virus-based nanoparticles to functionally alter the osteogenic differentiation of human mesenchymal stem cells

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Chinese Chemical Letters 2023年第1期34卷 215-220页

作者： Fei Xue jeroen J.L.M.Cornelissen Quan Yuan Shuqin Cao State Key Laboratory of Oral Diseases West China Hospital of StomatologySichuan UniversityChengdu 610041China Department of Molecules&Materials MESA+Institute for NanotechnologyUniversity of TwenteEnschede AE 7500the Netherlands

Micro RNA-26a(miR-26a)has been verified to promote osteogenic differentiation of mesenchymal stem cells in recent *** main obstacles to its application in bone regeneration are instability in the physiological environment and low efficiency of cellular membrane *** overcome these problems,we constructed a novel plant virus gene delivery system based on Cowpea chlorotic mottle virus(CCMV).By encapsulating miR-26a with purified capsid protein(CP)dimers derived from CCMV,CPmiR-26a(CP26a)virus-like particles(VLPs)were ***26a retained a structure similar to the native CCMV and protected miR-26a from digestion with its exterior ***,CP26a featured similar cellular uptake efficiency,osteogenesis promotion ability,and better biocompatibility compared with Lipofectamine2000-miR-26a(lipo26a),which indicated a promising prospect for CCMV as a novel gene delivery system.

关键词： VLPs Cowpea chlorotic mottle virus Gene delivery MicroRNAs Osteogenesis

High-gain waveguide amplifiers in SigN4 technology via double-layer monolithic integration

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Photonics Research 2020年第10期8卷 1634-1641页

作者： JINFENG MU MEINDERT DIJKSTRA jeroen KORTERIK HERMAN OFFERHAUS ANDSONIA M.GARCIA-BLANCO Optical Sciences Group MESA+Institute for NanotechnologyUniversity of Twente750O AE EnschedeThe Netheriands

Silicon nitride(SiN)-on-SiO,attracts increasing interest in integrated photonics owing to its low propagation loss and wide transparency window,extending from^400 nm to 2350 *** integration of active devices such as amplifiers and lasers on the Si;N,platform will enable applications requiring optical gain and a much-nceded alternative to hybrid integration,which suffers from high cost and lack of high-volume *** demonstrate a high-gain optical amplifier in Al2O3:Er^3+ monolithically integrated on the Si3N4 platform using a double photonic layer *** device exhibits a net Si3N4-to-Si3N4 gain of 18.11±0.9 dB at 1532 nm,and a broadband gain operation over 70 nm covering wavelengths in the S-,C-and *** work shows that rare-carth-ion-doped materials and in particular,rare-earth-ion-doped Al.05,can provide very high net amplification for the Si3N4 platform,paving the way to the development of different active devices monolithically integrated in this passive platform.

关键词： amplifiers waveguide amplifier

Muscle recruitment patterns and saddle pressure indexes with alterations in effective seat tube angle

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Sports Medicine and Health Science 2022年第1期4卷 29-37页

作者： Reece McDonald Wendy Holliday jeroen Swart Department of Human Biology Faculty of Health SciencesUniversity of Cape TownSouth Africa

Alteration of the effective seat tube angle(ESTA)may affect muscle activation patterns of the lower limbs in *** is conflicting evidence due to inadequate kinematic controls in previous *** primary aim of this study was to determine the muscle activity of seven lower limb muscles during alterations of the ESTA by altering the position of both the handlebars and saddle forwards or backwards by 3 cm while ensuring controlled ***,to determine the effect on the saddle pressure *** participants performed two 5 min electromyography(EMG)trials at 70%of peak power output(PPO)for three consecutive *** was a significant increase in muscle activity in the biceps femoris,gluteus maximus,and medial gastrocnemius with reductions in ESTA while a significant increase in tibialis anterior with increases in ESTA was *** pressure indices demonstrated a significant change in frontal versus back pressure as well as mean pubic pressure with changes in *** in the ESTA affects muscle activity in some,but not all of the lower limb *** research needs to be conducted to adequately understand the mechanism behind the differences in muscle activation.

关键词： EMG Muscle recruitment Seat tube angle Pressure mapping

RasGRP Ras guanine nucleotide exchange factors in cancer

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Frontiers in Biology 2013年第5期8卷 508-532页

作者： Olga KSIONDA Andre LIMNANDER jeroen P. ROOSE Department of Anatomy University of California San Francisco San Francisco CA 94143 USA

RasGRP proteins are activators of Ras and other related small GTPases by the virtue of functioning as guanine nucleotide exchange factors （GEFs）. In vertebrates, four RasGRP family members have been described. RasGRP-1 through -4 share many structural domains but there are also subtle differences between each of the different family members. Whereas SOS RasGEFs are ubiquitously expressed, RasGRP proteins are expressed in distinct patterns, such as in different cells of the hematopoietic system and in the brain. Most studies have concentrated on the role of RasGRP proteins in the development and function of immune cell types because of the predominant RasGRP expression profiles in these cells and the immune phenotypes of mice deficient for Rasgrp genes. However, more recent studies demonstrate that RasGRPs also play an important role in tumorigenesis. Examples are skin- and hematological- cancers but also solid malignancies such as melanoma or prostate cancer. These novel studies bring up many new and unanswered questions related to the molecular mechanism of RasGRP-driven oncogenesis, such as new receptor systems that RasGRP appears to respond to as well as regulatory mechanisms for RasGRP expression that appear to be perturbed in these cancers. Here we will review some of the known aspects of RasGRP biology in lymphocytes and will discuss the exciting new notion that RasGRP Ras exchange factors play a role in oncogenesis downstream of various growth factor receptors.

关键词： Ras signaling lymphocytes cancer RasGRP receptor

TRADE-OFFS IN THE DESIGN OF SUSTAINABLE CROPPING SYSTEMS AT A REGIONAL LEVEL:A CASE STUDY ON THE NORTH CHINA PLAIN

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Frontiers of Agricultural Science and Engineering 2022年第2期9卷 295-308页

作者： jeroen C.J.GROOT Xiaolin YANG Farming Systems Ecology Wageningen University&ResearchP.O.Box 4306700 AK Wageningenthe Netherlands International Maize and Wheat Improvement Center(CIMMYT) Sustainable Intensification ProgramCarretera México-VeracruzKm.45El Batán56237 TexcocoMéxico Alliance of Bioversity International and CIAT PerformanceInnovation and Strategic Analysis for Impact unitVia di San Domenico 100153 RomeItaly College of Water Resources&Civil Engineering China Agricultural UniversityBeijing 100193China

Since the Green Revolution cropping systems have been progressively homogenized and intensified with increasing rates of inputs such as fertilizers,pesticides and *** has resulted in higher crop productivity but also a high environmental burden due to increased pollution and water *** identify opportunities for increasing the productivity and reducing the environmental impact of cropping systems,it is crucial to assess the associated *** paper presents a model-based analysis of how 30 different crop rotations practiced in the North China Plain could be combined at the regional level to overcome trade-offs between indicators of economic,food security,and environmental *** model uses evolutionary multi-objective optimization to maximize revenues,livestock products,dietary and vitamin C yield,and to minimize the decline of the groundwater *** modeling revealed substantial trade-offs between objectives of maximizing productivity and profitability versus minimizing ground water decline,and between production of livestock products and vitamin C *** strategies each defining a specific combination of cropping systems and contributing to different extents to the various objectives were *** of these six strategies could be used to find opportunities to mitigate the tradeoffs between *** was concluded that a holistic analysis of the potential of a diversity cropping systems at a regional level is needed to find integrative solutions for challenges due to conflicting objectives for food production,economic viability and environmental protection.

关键词： crop rotation food security multi-objective optimization water use