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Deformable microlaser force sensing

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Light(Science & Applications) 2024年第6期13卷 1196-1209页

作者： Eleni Dalaka Joseph Shill Jonathan h.h.Booth Anna Popczyk Stefan R.Pulver Malte C.Gather Marcel Schubert Centre of Biophotonics SUPASchool of Physics and AstronomyUniversity of St AndrewsNorth HaughSt AndrewsUK humboldt Centre for Nano-and Biophotonics Department of ChemistryUniversity of CologneKölnGermany School of Psychology and Neuroscience University of St AndrewsSt Mary’s QuadSouth StreetSt AndrewsUK Institute for Bioengineering of Catalonia BarcelonaSpain

Mechanical forces are key regulators of cellular behavior and function,affecting many fundamental biological processes such as cell migration,embryogenesis,immunological responses,and pathological *** force sensors and imaging techniques have been developed to quantify these otherwise invisible forces in single cells and in ***,current techniques rely heavily on high-resolution microscopy and do not allow interrogation of optically dense tissue,reducing their application to 2D cell cultures and highly transparent biological ***,we introduce DEFoRM,deformable microlaser force sensing,a spectroscopic technique that detects sub-nanonewton forces with unprecedented spatio-temporal *** is based on the spectral analysis of laser emission from dye-doped oil microdroplets and uses the force-induced lifting of laser mode degeneracy in these droplets to detect nanometer *** validation by atomic force microscopy and development of a model that links changes in laser spectrum to applied force,DEFoRM is used to measure forces in 3D and at depths of hundreds of microns within tumor spheroids and late-stage Drosophila *** furthermore show continuous force sensing with single-cell spatial and millisecond temporal resolution,thus paving the way for non-invasive studies of biomechanical forces in advanced stages of embryogenesis,tissue remodeling,and tumor invasion.

关键词： invasion otherwise hundreds

Advances in human stem cell therapies:pre-clinical studies and the outlook for central nervous system regeneration

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Neural Regeneration Research 2021年第4期16卷 614-617页

作者： Lindsey h.Forbes Melissa R.andrews Medical Research Council Centre for Reproductive health The Queen’s Medical Research InstituteUniversity of EdinburghEdinburghUK School of Biological Sciences University of SouthamptonSouthamptonUK

Cell transplantation has come to the forefront of regenerative medicine alongside the discovery and application of stem cells in both research and clinical *** are several types of stem cells currently being used for pre-clinical regenerative therapies,each with unique characteristics,benefits and *** brief review will focus on recent basic science advancements made with embryonic stem cells and induced pluripotent stem *** embryonic stem cells and induced pluripotent stem cells provide platforms for new neurons to replace dead and/or dying cells following *** to their capacity for reprogramming and differentiation into any neuronal type,research in preclinical rodent models has shown that embryonic stem cells and induced pluripotent stem cells can integrate,survive and form connections in the nervous system similar to de novo *** forward however,there are some limitations to consider with the use of either stem cell ***,embryonic stem cells are not an ideal source of cells,genetically,induced pluripotent stem cells are not ideal in terms of personalized treatment for those with certain genetic diseases the latter of which may guide regenerative medicine away from personalized stem cell based therapies and into optimized stem cell ***,the potential of these stem cells in central nervous system regenerative therapy is only beginning to be *** example,through genetic modification,stem cells serve as ideal platforms to reintroduce missing or downregulated molecules into the nervous system to further induce regenerative *** this review,we highlight the limitations of stem cell based therapies whilst discussing some of the means of overcoming these limitations.

关键词： cell transplantation central nervous system regeneration embryonic stem cells induced pluripotent stem cells spinal cord injury

Restoring axonal localization and transport of transmembrane receptors to promote repair within the injured CNS: a critical step in CNS regeneration

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Neural Regeneration Research 2017年第1期12卷 27-30页

作者： Lindsey h.Forbes Melissa R.andrews School of Medicine University of St.Andrews Biological Sciences University of Southampton

Each neuronal subtype is distinct in how it develops,responds to environmental cues,and whether it is capable of mounting a regenerative response following *** the adult central nervous system（CNS） does not regenerate,several experimental interventions have been trialled with successful albeit limited instances of axonal *** highlight here some of these approaches including extracellular matrix（ECM） modification,cellular grafting,gene therapy-induced replacement of proteins,as well as application of *** also review the recent report demonstrating the failure of axonal localization and transport of growth-promoting receptors within certain classes of mature *** specifically,we discuss an inability of integrin receptors to localize within the axonal compartment of mature motor neurons such as in the corticospinal and rubrospinal tracts,whereas in immature neurons of those pathways and in mature sensory tracts such as in the optic nerve and dorsal column pathways these receptors readily localize within *** we assert that this failure of axonal localization contributes to the intrinsic inability of axonal *** conclude by highlighting the necessity for both combined therapies as well as a targeted approach specific to both age and neuronal subtype will be required to induce substantial CNS repair.

关键词： axonal transport cellular therapies extracellular matrix gene therapy integrin regeneration viral vectors

Soil carbon stock and emission: estimates from three land-use systems in Ghana

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Ecological Processes 2021年第1期10卷 157-169页

作者： Joseph Anokye Vincent Logah andrews opoku Department of Crop and Soil Sciences Kwame Nkrumah University of Science and Technology(KNUST)KumasiGhana

Background:Land-use systems that sequester carbon and reduce Co_(2) emissions are key in the global mitigation strategies of climate *** gas emission from agro-ecosystems in sub-Saharan Africa is little ***,we quantified soil carbon stock(SCS)and Co_(2) emissions from three land-use systems *** land,oil palm plantation and forestland in the semi-deciduous forest zone of ***:Soil organic carbon concentration at the 0–15 cm layer in the forestland was 62 and 23%greater than that in the arable land and palm plantation,*** SCS along the 1.0-m profile was 108.2,99.0 and 73.5 Mg ha^(−1) in the forestland,palm plantation and arable land,*** land emitted 30–46%more Co_(2) than palm plantation and *** the dry season,Co_(2) emissions were respectively 0.93,0.63 and 0.5 kg ha^(−1) h−1 from the arable land,palm plantation and *** relationships were observed between Co_(2) emissions and SCS,soil temperature,and *** SCS greatly influenced Co_(2) emission in the dry season more than in the wet season in the relatively higher carbon-input systems(forestland and palm plantation).Soil temperature accounted for more than 55%of Co_(2) emissions in both seasons,which has implications in the era of rising global ***:The study provides relevant information on carbon storage abilities of the three land-use types in tropical climate and calls for drastic climate change actions to reduce degradation of forest cover and soil disturbance in agro-ecosystems in sub-Saharan Africa.

关键词： Arable land Carbon dioxide emission Climate change Soil moisture Soil temperature Sub-Saharan Africa

Thiopurines are negatively associated with anthropometric parameters in pediatric Crohn's disease

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World Journal of Gastroenterology 2018年第18期24卷 2036-2046页

作者： Neera Gupta Robert h Lustig Cewin Chao Eric Vittinghoff howard andrews Cheng-Shiun Leu Division of Gastroenterology and Nutrition Department of Pediatrics Weill Cornell Medicine Division of Endocrinology Department of Pediatrics University of CaliforniaSan Francisco Department of Nutrition and Food Services University of CaliforniaSan Francisco Department of Epidemiology and Biostatistics University of CaliforniaSan Francisco Department of Biostatistics Mailman School of Public Health Columbia University Department of Biostatistics Columbia University Medical Center

AIM To determine the distribution of anthropometric parameter(AP)-z-scores and characterize associations between medications/serum biomarkers and AP-z-scores in pediatric Crohn's disease(CD).METhoDS CD patients [hronological age(CA) 21 years] were enrolled in a cross-sectional study. Descriptive statistics were generated for participants' demographic characteristics and key variables of interest. Paired t-tests were used to compare AP-z-scores calculated based on CA(CA z-scores) and bone age(BA)(BA z-scores) for interpretation of AP's. Linear regression was utilized to examine associations between medications and serum biomarkers with AP-z-scores calculated based on CA(n = 82) and BA(n = 49). We reported regression coefficients as well as their corresponding p-values and 95% confidence *** Mean CA at the time of the study visit was 15.3 ± 3.5(SD; range = 4.8-20.7) years. Mean triceps skinfold(P = 0.039), subscapular skinfold(P = 0.002) and midarm circumference(MAC)(P = 0.001) BA z-scores were higher than corresponding CA z-scores. Medications were positively associated with subscapular skinfold [adalimumab(P = 0.018) and methotrexate(P = 0.027)] and BMI CA z-scores [adalimumab(P = 0.029)]. Azathioprine/6-mercaptopurine were negatively associated with MAC(P = 0.045), subscapular skinfold(P = 0.014), weight(P = 0.002) and BMI(P = 0.013) CA z-scores. ESR, CRP, and WBC count were negatively associated, while albumin and IGF-1 BA z-scores were positively associated, with specific AP z-scores(P height CA z-scores were higher in females, not males, treated with infliximab(P = 0.038). hemoglobin(P = 0.018) was positively associated, while platelets(P = 0.005), ESR(P = 0.003) and CRP(P = 0.039) were negatively associated with height CA z-scores in males, not females. CoNCLUSIoN our results suggest poor efficacy of thiopurines and a possible sex difference in statural growth response to infliximab in pediatric CD. Prospective longitudinal studie

关键词： Inflammatory bowel disease Azathioprine/6-mercaptopurine Biologics Nutrition

Kinetics of hydrogen peroxide quenching following UV/h_(2)o_(2)advanced oxidation by thiosulfate,bisulfite,and chlorine in drinking water treatment

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Frontiers of Environmental Science & Engineering 2023年第12期17卷 59-69页

作者： Tianyi Chen Lizbeth Taylor-Edmonds Susan andrews Ron hofmann Department of Civil and Mineral Engineering University of TorontoTorontoOntario M5S 1A4Canada

Residual h_(2)o_(2)from UV/h_(2)o_(2)treatment can be quenched by thiosulfate,bisulfite,and chlorine,but the kinetics of these reactions have not been reported under the full range of practical *** this study,the rates of h_(2)o_(2)quenching by these compounds were compared in different water matrices,temperatures,ph,and when using different forms of bisulfite and *** general,it was confirmed that thiosulfate would be too slow to serve as a quenching agent in most practical *** ph 7-8.5,chlorine tends to quench h_(2)o_(2)more than 20 times faster than bisulfite in the various conditions *** important observation was that in lightly-buffered water(e.g.,alkalinity of 20 mg/L as CaCo_(3)),the form of chlorine can have a large impact on quenching rate,with gaseous chlorine slowing the reaction due to its lowering of the ph,and hypochlorite having the opposite *** impacts will become less significant when water buffer capacity(i.e.,alkalinity)increases(e.g.,to 80 mg/L as CaCo_(3)).In addition,water temperature should be considered as the time required to quench h_(2)o_(2)by chlorine at 4℃is up to 3 times longer than at 20℃.

关键词： UV/h_(2)o_(2) h_(2)o_(2) quenching Chlorine type Water alkalinity Temperature

Impact of carbon-based nutrient enhancement on biofiltration performance for drinking water treatment

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Journal of Environmental Sciences 2019年第8期31卷 124-131页

作者： Yu Zhao Liz Taylor-Edmonds Robert C.andrews Department of Civil and Mineral Engineering University of Toronto

Incorporation of a carbon-based nutrient enhancementstrategy for drinking water biofiltration is an attractive option, especially for source waters which contain recalcitrant organics. This study compared biofilters that were operated in parallel and individually enhanced with amino acids(including alanine, phenylalanine, and tryptophan), inulin, and sucrose to increase biomass concentration and promote biodegradation of dissolved organic carbon(DoC) in the source water, including disinfection by-product(DBP) precursors. Biomass activity was characterized by measuring adenosine tri-phosphate(ATP), dissolved oxygen(Do) consumption, and through the use of laccase and esterase enzyme assays. Performance was evaluated in terms of headloss,turbidity, p h, DoC, UV254, and DBP formation potential(DBP FP). The introduction of carbonbased nutrients significantly increased biomass activity, where ATP values peaked at 976 ng/g of filter media, 853 ng/g, and 513 ng/g for amino acids, inulin, and sucrose-spiked biofilters,respectively, while a non-spiked control only reached 104 ng/g. Do utilization by the enhanced biofilters was significantly higher than the control, with a strong correlation between ATP and Do uptake observed for all filters(R^2> 0.74). Laccase and esterase enzyme activities of enhanced biofilters were also elevated(p > 0.05), suggesting greater biodegradation potential. operational parameters such as headloss development and turbidity control were not impaired by carbon supplementation strategies or an increase in biomass concentration and activity. however, the enhancement strategy did not provide improvement in terms of source water carbon removal(DoC and UV254) or DBP FP when treated filters were compared to a control.

关键词： Biological filtration Carbon enhancement Biomass Disinfection by-products Dissolved organic carbon

human pluripotent stem cells:tools for regenerative medicine

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Biomaterials Translational 2021年第4期2卷 294-300页

作者： Peter W.andrews The Centre for Stem Cell Biology The School of BioscienceThe University of SheffieldSheffieldUK

human embryonic stem cells and induced pluripotent stem cells,together denoted as pluripotent stem cells have opened up unprecedented opportunities for developments in human healthcare over the past 20 *** much about the properties and behaviour of these cells required to underpin their applications has been discovered over this time,a number of issues *** brief review considers the history of these developments and some of the underlying biology,pointing out some of the problems still to be resolved,particularly in relation to their genetic stability and possible malignancy.

关键词： embryonic stem cell induced pluripotent stem cell human pluripotency differentiation

Reduced normogastric electrical activity associated with emesis:A telemetric study in ferrets

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World Journal of Gastroenterology 2009年第48期15卷 6034-6043页

作者： Nathalie Percie du Sert Kit M Chu Man K Wai John A Rudd Paul LR andrews Division of Basic Medical Sciences St.George's University of LondonCranmer Terrace Emesis Research Group School of Biomedical SciencesFaculty of MedicineThe Chinese University of Hong KongShatinNew Territories

AIM： To characterize the gastric myoelectric activity （GMA） and intra-abdominal pressure changes induced by emetic stimuli （apomorphine and cisplatin） in the ferret. METhoDS： GMA and intra-abdominal pressure were recorded in conscious, unrestrained ferrets surgically implanted with radiotelemetry transmitters. Animals were challenged with apomorphine （0.25 mg/kg sc） and cisplatin （10 mg/kg ip）, and the emetic response was quantified via direct observation and intra-abdominal pressure recording for 1 and 4 h, respectively. The GMA was analyzed by spectral analysis; the parameters used to characterize the GMA were the dominant frequency （DF） and the repartition of spectral power in the bradygastric, normogastric and tachygastric frequency ranges. RESULTS： Retches were identified on the intraabdominal pressure trace as peaks 0.30 ± 1.01 s in duration and 59.57 ± 2.74 mmhg in amplitude, vomit peaks were longer （0.82 ± 0.06 s, P 〈 0.01） and reached a higher pressure （87.73 ± 8.12 mmhg, P 〈 0.001）. The number of retches and vomits quantified via direct observation [apomorphine： 65.5 ± 11.8 retches ± vomits （R＋V）, cisplatin： 202.6 ± 64.1 R＋V] and intra-abdominal pressure （apomorphine： 68.3± 13.7 R＋V, n = 8; cisplatin： 219.0 ± 69.2 R＋V, n = 8） were correlated （r = 0.97, P 〈 0.0001） and the timing of emesis was consistent between the 2 methods. Apomorphine induced a decrease in normogastria from 45.48% ± 4.35% to 36.70 ± 4.34% （n = 8, P 〈 0.05） but the DF of the slow waves was not changed [8.95 ± 0.25 counts/rain （cpm） vs 8.68 ± 0.35 cpm, n = 8, P 〉 0.05]. Cisplatin induced a decrease in normogastria from 55.83% ± 4.30% to 29.22% ± 5.16% and an increase in bradygastria from 14.28% ± 2.32% to 31.19% ± 8.33% （n = 8, P 〈 0.001） but the DF （9.14 ± 0.13 cpm） remained unchanged （P 〉 0.05）. The GMA changes induced by cisplatin preceded the emetic response as normogastria was reduced for 1 h before the onset of emesis （57.61% ± 5.66% to 39.91% ± 5.74%, n = 6, P 〈 0.05）. Peri-emesis

关键词： Emesis Nausea Stomach Ferret Cisplatin Apomorphine Electromyography