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New insights into the vitamin D requirements during pregnancy

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Bone Research 2017年第3期5卷 161-176页

作者： Bruce W Hollis Carol l wagner Department of Pediatrics Darby Children's Research Institute Medical University of South Carolina

Pregnancy represents a dynamic period with physical and physiological changes in both the mother and her developing fetus. The dramatic 2-3 fold increase in the active hormone 1,25（OH）2D concentrations during the early weeks of pregnancy despite minimal increased calcium demands during that time of gestation and which are sustained throughout pregnancy in both the mother and fetus suggests an immunomodulatory role in preventing fetal rejection by the mother. While there have been numerous observational studies that support the premise of vitamin D＇s role in maintaining maternal and fetal well-being, until recently, there have been few randomized clinical trials with vitamin D supplementation. One has to exhibit caution, however, even with RCTs, whose results can be problematic when analyzed on an intent-to-treat basis and when there is high non-adherence to protocol （as if often the case）, thereby diluting the potential good or harm of a given treatment at higher doses. As such, a biomarker of a drug or in this case ＂vitamin＂ or pre-prohormone is better served. For these reasons, the effect of vitamin D therapies using the biomarker circulating 25（OH）D is a far better indicator of true ＂effect.＂ When pregnancy outcomes are analyzed using the biomarker 25（OH）D instead of treatment dose, there are notable differences in maternal and fetal outcomes across diverse racial/ethnic groups, with improved health in those women who attain a circulating 25（OH）D concentration of at least 100 nmol. l-1 （40 ng. ml-1）. Because ,an important issue is the timing or initiation of vitamin D treatment/supplementation, and given the potential effect of vitamin D on placental gene expression and its effects on inflammation within the placenta, it appears crucial to start vitamin D treatment before placentation （and trophoblast invasion）; however, this question remains unanswered. Additional work is needed to decipher the vitamin D requirements of pregnant women and the optimal timing of s

关键词： New insights into the vitamin D requirements during pregnancy

Barring the gates to the battleground:DDR1 promotesimmune exclusion in solid tumors

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Signal Transduction and Targeted Therapy 2022年第2期7卷 339-340页

作者： Dimitrios l.wagner Enrico Klotzsch Berlin Center for Advanced Therapies(BeCAT)and BIH Center for Regenerative Therapies(BCRT) Charité-Universitätsmedizin BerlinAugustenburger Platz 113353BerlinGermany Institute for Biology Experimental Biophysics/MechanobiologyHumboldt University of BerlinBerlinGermany laboratory of Applied Mechanobiology Department for Health Sciences and TechnologyETH ZurichZurichSwitzerland

In a recent article in Nature,Sun et al.1 identify a novel mechanism of how solid tumors prevent immune cell infiltration into cancer tissue by ***,they develop and test a new monoclonal antibody that may be used as a... 详细信息

关键词： tumors immune

Biomaterials for refractive correction:corneal onlays and inlays

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Science China Chemistry 2014年第4期57卷 501-509页

作者： WU Jian FUNDERBURGH James l wagner William R McGowan Institute for Regenerative Medicine University of Pittsburgh Department of Surgery University of Pittsburgh School of Medicine Department of Ophthalmology University of Pittsburgh School of Medicine Department of Bioengineering University of Pittsburgh

Corneal inlays and onlays represent a means of providing patients with permanent refractive error correction. As an alternative to conventional spectacles and contact lens, these techniques are less invasive compared with laser-based refractive surgery and are reversible. In this review, we provide a brief overview of the anatomic microstructure of the human cornea, indicating the primary physiological function for each component. Next, the wide range of biomaterials used as corneal inlays and onlays are considered, from synthetic polymers to biological components derived from the extracellular matrix. The limitations and challenges associated with the most common materials are discussed as is the need to improve their properties to achieve long-term, complication-free intraocular implantation. Finally, the prospect of applying tissue engineering strategies is noted for its potential to generate autologous corneal tissue that could be implanted as the optimal inlay or onlay materials.

关键词： refractive error onlays inlays synthetic polymer biological extracellular matrix refractive surgery

Invading target cells: multifunctional polymer conjugates as therapeutic nucleic acid carriers

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Frontiers of Chemical Science and Engineering 2011年第3期5卷 275-286页

作者： Ulrich lÄCHElT Ernst wagner Pharmaceutical Biotechnology Center for System-based Drug Researchand Center for NanoScienceLudwig-Maximilians-Universität MunichButenandtstrasse 5-13D-81377 MunichGermany

Polymer-based conjugates are an interesting option and challenge for the design of nano-sized drug-delivery systems,as they require advanced conjugation chemistry and precise *** the case of nucleic acid therapy,non-viral carriers face several biological barriers during the delivery process,namely 1)protection of the cargo from extracellular degradation,2)avoidance of non-specific interactions with non-targeted tissues,3)efficient entry into the target cells,4)intracellular trafficking to the site of action and 5)cargo *** take on these obstacles,multifunctional conjugates can act as“smart polymers”with microenvironment-sensing dynamics to facilitate the separate delivery *** of defined polymer architectures with precise functionali-zation enables structure-activity relationships to be inves-tigated and the integration of key functions for efficient *** bioresponsive polymer conjugates,which are equipped with molecular devices responding to the certain microenvironments within the delivery pathway(***,redox potential,enzymes)can be *** review focuses on the modular engineering and conjuga-tion of multifunctional polymeric structures for the utilization as“tailor-made”nucleic acid carriers.

关键词： conjugate DNA gene transfer polymer RNA targeting

Geochemical Evaluation of the Permian Ecca Shale in Eastern Cape Province, South Africa:Implications for Shale Gas Potential

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Acta Geologica Sinica(English Edition) 2018年第3期92卷 1193-1217页

作者： Christopher BAIYEGUNHI Kuiwu lIU Nicola wagner Oswald GWAVAVA Temitope l.OlONINIYI Department of Geology University of Fort Hare Department of Geology University of Johannesburg

Shale gas has been the exploration focus for future energy supply in South Africa in recent time. Specifically, the Permian black shales of the Prince Albert, Whitehill, Collingham, Ripon and Fort Brown Formations are considered to be most prospective rocks for shale gas exploration. In this study,outcrop and core samples from the Ecca Group were analyzed to assess their total organic carbon(TOC), organic matter type, thermal maturity and hydrocarbon generation potential. These rocks have TOC ranging from 0.11 to 7.35 wt%. The genetic potential values vary from 0.09 to 0.53 mg HC/g,suggesting poor hydrocarbon generative potential. Most of the samples have Hydrogen Index(HI) values of less than 50 mg HC/g TOC, thus suggesting Type-Ⅳ kerogen. Tmax values range from 318℃ to601℃, perhaps indicating immature to over-maturity of the samples. The vitrinite reflectance values range from 2.22% to 3.93%, indicating over-maturity of samples. Binary plots of HI against Oxygen Index(OI), and HI versus Tmax show that the shales are of Type II and mixed Type Ⅱ-Ⅲ *** on the geochemical data, the potential source rocks are inferred as immature to over-matured and having present-day potential to produce gas.

关键词： geochemistry organic matter type thermal maturity hydrocarbons Ecca Group South Africa

The impact of weather on summer and winter exercise behaviors

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Journal of Sport and Health Science 2019年第1期8卷 39-45页

作者： Abram l.wagner Florian Keusch Ting Yan Philippa J.Clarke Department of Epidemiology University of Michigan Institute for Social Research University of Michigan

Background: Outdoor exercise is an enjoyable way for individuals to improve fitness, but it is dependent on weather conditions. This study examines the association between weather conditions and outdoor exercise after adjustment for age, sex, race, and socioeconomic ***: We used data representative of American adults from the University of Michigan/Thomson Reuters June 2013 surveys of consumers(core and supplement) to investigate self-reported exercise behavior in summer and winter. Multivariate multinomial logistic regression models estimated the odds of delayed or indoor exercise compared with outdoor ***: Of the 502 respondents, 16.3% did not regularly exercise outdoors(i.e., at least once a week), and many would delay exercise both in summer(51.8%) and winter(43.9%). Individuals listing rain as the predominant adverse weather condition had 3.33 times higher odds of exercising indoors(95% confidence interval(CI): 1.34-8.28) and 3.49 times higher odds of delaying exercise(95%CI: 1.69-7.21) compared with those mentioning heat as the predominant adverse condition. Individuals for whom ice or snow was an adverse winter weather condition were more likely to delay exercise(odds ratio(OR) = 3.34; 95%CI: 1.19-9.36), compared with those concerned with ***: This study found that race, age, and education exacerbate the negative effects of adverse weather conditions on the decision to exercise outdoors. Accordingly, any recommendation for an individual to exercise outdoors should be combined with an evaluation of the individual's outdoor environment along with strategies for the individual to continue exercising, indoors or outdoors, when adverse weather is present.

关键词： Outdoor exercise Physical activity Rain Seasons Snow Survey

Tunable photocycle kinetics of a hybrid bacteriorhodopsin/quantum dot system

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Nano Research 2019年第2期12卷 365-373页

作者： Terianna J. Wax Jordan A. Greco Shutang Chen Nicole l. wagner Jing Zhao Robert R. Birge 55 North Eagleville Rd Department of Chemistry University of Connecticut Storrs CT 06269-3060 USA

The inclusion of inorganic nanoparticles in biological environments has led to the creation of hybrid nanosystems that are employed in a variety of applications. One such system includes quantum dots (QDs) coupled with the photoactive protein, bacteriorhodopsin (BR), which has been explored in developing enhanced photovoltaic devices. In this work, we have discovered that the kinetics of the BR photocycle can be manipulated using CdSe/CdS (core/shell) QDs. The photocycle lifetime of protein samples with varying QD amounts were monitored using time-resolved absorption spectroscopy. Concentration-dependent elongations of the bR and M state lifetimes were observed in the kinetic traces, thus suggesting that excitonic coupling occurs between BR and QDs. We propose that the pairing of BR with QDs has the potential to be utilized in protein-based computing applications, specifically for real-time holographic processors, which depend on the temporal dynamics of the bR and M photointermediates.

关键词： bacteriorhodopsin photocycle bionanotechnology photochromism quantum dot hybrid materials

Analysis of metabolic alterations in Arabidopsis following changes in the carbon dioxide and oxygen partial pressures

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Journal of Integrative Plant Biology 2014年第9期56卷 941-959页

作者： Alexandra Florian Stefan Timm Zoran Nikoloski Takayuki Tohge Hermann Bauwe wagner l.Araujo Alisdair R.Fernie Max Planck Institute for Molecular Plant Physiology Department of Plant Physiology University of Rostock Max-Planck Partner group at the Departament of Plant Biology Federal University of Vicosa

As sessile organisms,plants are subject to a multitude of environmental variations including several which directly affect their interaction with the *** the indiscriminant nature of Rubisco,the relative rates of photosynthesis and photorespiration are known to be responsive to changes in gas ***,comprehensive profiling methods have not yet been applied in order to characterize the wider consequences of these changes on primary metabolism in ***,although transcriptional profiling has revealed that a subset of photorespiratory enzymes are co-expressed,whether transcriptional responses play a role in short-term responses to atmospheric compositional changes remains *** address these questions,plants Arabidopsis thaliana（Arabidopsis） ecotype Columbia（Col-O） grown under normal air conditions were transferred to different CO_2 and O_2 concentrations and characterized at the physiological,molecular,and metabolic levels following this *** results reveal alterations in the components,which are directly involved in,or supporting,photorespiration,including transcripts and metabolite *** results further highlight that the majority of the regulation of these pathways is not mediated at the level of transcription and that the photorespiratory pathway is essential also in conditions in which flux through the pathway is minimized,yet suggest that flux through this pathway is not mediated at the level of transcription.

关键词： Carbon dioxide partial pressures gene expression metabolic profiling oxygen partial pressures

Predictors of mortality and endoscopic intervention in patients with upper gastrointestinal bleeding in the intensive care unit

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Gastroenterology Report 2020年第4期8卷 299-305,I0002页

作者： Vijaya l.Rao Nina Gupta Eric Swei Thomas wagner Andrew Aronsohn KGautham Reddy Neil Sengupta Section of Gastroenterology Hepatology and NutritionDepartment of Internal MedicineUniversity of Chicago MedicineChicagoILUSA Department of Internal Medicine University of Chicago MedicineChicagoILUSA

Background:The outcomes of patients undergoing esophagogastroduodenoscopy(EGD)in the intensive care unit(ICU)for upper gastrointestinal bleeding(UGIB)are not well *** aims were to determine predictors of 30-day mortality and endoscopic intervention,and assess the utility of existing clinical-prediction tools for UGIB in this ***:Patients hospitalized in an ICU between 2008 and 2015 who underwent EGD were identified using a validated,machine-learning *** regression was used to determine factors associated with 30-day mortality and endoscopic *** under receiver-operating characteristics(AUROC)analysis was used to evaluate established UGIB scoring systems in predicting mortality and endoscopic intervention in patients who presented to the hospital with ***:A total of 606 patients underwent EGD for UGIB while admitted to an *** median age of the cohort was 62 years and 55.9%were *** analysis revealed that predictors associated with 30-day mortality included American Society of Anesthesiologists(ASA)class(odds ratio[OR]4.1,95%confidence interval[CI]2.2-7.9),Charlson score(OR 1.2,95%CI 1.0-1.3),and duration from hospital admission to EGD(OR 1.04,95%CI 1.01-1.07).Rockall,Glasgow-Blatchford,and AIMS65 scores were poorly predictive of endoscopic intervention(AUROC:0.521,0.514,and 0.540,respectively)and in-hospital mortality(AUROC:0.510,0.568,and 0.506,respectively).Conclusions:Predictors associated with 30-day mortality include ASA classification,Charlson score,and duration in the hospital prior to *** risk tools are poorly predictive of clinical outcomes,which highlights the need for a more accurate risk-stratification tool to predict the benefit of intervention within the ICU population.

关键词： upper gastrointestinal bleeding esophagogastroduodenoscopy intensive care unit