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A tissue-engineered rostral migratory stream for directed neuronal replacement

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Neural Regeneration Research 2018年第8期13卷 1327-1331页

作者： john c.O'donnell Kritika S.Katiyar Kate V.Panzer d.Kacy cullen center for Brain Injury & Repair Department of Neurosurgery Perelman School of Medicine University of Pennsylvania center for Neurotrauma Neurodegeneration & Restoration Corporal Michael Crescenz Veterans Affairs Medical Center School of Biomedical Engineering Drexel University department of Bioengineering School of Engineering and Applied Science University of Pennsylvania

New neurons are integrated into the circuitry of the olfactory bulb throughout the lifespan in the mamma- lian brain--including in humans. These new neurons are born in the subventricular zone and subsequently mature as they are guided over long distances via the rostral migratory stream through mechanisms we are only just beginning to understand. Regeneration after brain injury is very limited, and although some neuroblasts from the rostral migratory stream will leave the path and migrate toward cortical lesion sites, this neuronal replacement is generally not sustained and therefore does not provide enough new neurons to alleviate functional deficits. Using newly discovered microtissue engineering techniques, we have built the first self-contained, implantable constructs that mimic the architecture and function of the rostral migratory stream. This engineered microtissue emulates the dense cord-like bundles of astrocytic somata and processes that are the hallmark anatomical feature of the glial tube. As such, our living microtissue-en- gineered rostral migratory stream can serve as an in vitro test bed for unlocking the secrets of neuroblast migration and maturation, and may potentially serve as a living transplantable construct derived from a patient＇s own cells that can redirect their own neuroblasts into lesion sites for sustained neuronal replace- ment following brain injury or neurodegenerative disease. In this paper, we summarize the development of fabrication methods for this microtissue-engineered rostral migratory stream and provide proof-of-princi- ple evidence that it promotes and directs migration of immature neurons.

关键词： rostral migratory stream glial tube astrocyte neuroblast brain injury neural repair neural regeneration tissue engineering

Effects of mountain pine beetle-killed forests on source water contributions to streamflow in headwater streams of the colorado Rocky Mountains

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Frontiers of Earth Science 2017年第3期11卷 496-504页

作者： christine E. WEHNER john d. STEdNIcK Watershed Science Program College of Natural Resources Colorado State University Fort Collins CO 80523-1472 USA

Natural or human-influenced disturbances are important to the health and diversity of forests, which in turn, are important to the water quantity and quality exported from a catchment. However, human-induced disturbances （prescribed fire and harvesting） have been decreasing, and natural disturbances （fires and insects） have been increasing in frequency and severity. One such natural disturbance is the mountain pine beetle （MPB）, （denclroctonus ponderosae） an endemic species. A recent epidemic resulted in the mortality of millions of hectares of lodgepole pine （Pinus contorta） forests in colorado, USA. Beetle-induced tree mortality brings about changes to the hydrologic cycle, including decreased transpiration and interception with the loss of canopy cover. This study examined the effect of the mountain pine beetle kill on source water contributions to streamflow in snowmelt- dominated headwater catchments using stable isotopes （2H and ~80） as tracers. Study catchments with varying level of beetle-killed forest area （6% to 97%） were sampled for groundwater, surface water, and precipitation. Streams were sampled to assess whether beetle-killed forests have altered source water contributions to streamflow. Ground- water contributions increased with increasing beetle-killed forest area （p = 0.008）. Both rain and snow contributions were negatively correlated with beetle-killed forest area （p = 0.035 and p = 0.011, respectively）. As the beetle-killed forest area increases, so does fractional groundwater contribution to streamflow.

关键词： mountain pine beetle isotope tracers stream-flow generation headwaters

Glucose metabolism in amyotrophic lateral sclerosis:it is bitter-sweet

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Neural Regeneration Research 2022年第9期17卷 1975-1977页

作者： Titaya Lerskiatiphanich Jianina Marallag john d.Lee School of Biomedical Sciences Faculty of MedicineThe University of QueenslandSt LuciaBrisbaneQLDAustralia

A recent study by Mcdonald et al.(2021)focused on how peripheral glucose metabolism and handling are compromised in amyotrophic lateral sclerosis(ALS).dysfunctions in glucose and energy metabolism have been identified in transgenic mouse models and patients with ***,how these processes are altered and contribute to disease progression are not fully *** aforementioned study has identified several changes to glucose homeostasis in the transgenic SOd1G93A mouse model of ALS at the later stages of the ***,the authors found that despite insulin resistance being present,there was increased glucose uptake in ALS mice,and increased glycogen accumulation in the ***,there was evidence of glucagon resistance developing in these mice,which supports clinical *** perspective outlines the key aspects of glucose metabolism and demonstrates how multiple pathways relating to these processes are compromised in ALS.

关键词： metabolism amyotrophic homeostasis

Behavior and physiology of mechanoreception: separating signal and noise

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Integrative Zoology 2009年第1期4卷 3-12页

作者： john c.MONTGOMERY Shane WINdSOR daniel BASSETT Leigh Marine Laboratory University of AucklandAucklandNew Zealand

The mechanosensory lateral line is found in all aquatic fish and *** provides a highly sensitive and versatile hydrodynamic sense that is used in a wide range of *** stimuli of biological interest originate from both abiotic and biotic sources,and include water currents,turbulence and the water disturbances caused by other animals,such as prey,predators and ***,the detection of biologically important stimuli often has to occur against a background of noise generated by water movement,or movement of the fish *** such,separating signal and noise is“of the essence”in understanding the behavior and physiology of *** we discuss general issues of signal and noise in the lateral-line system and the behavioral and physiological strategies that are used by fish to enhance signal detection in a noisy *** order for signal and noise to be separated,they need to differ,and we will consider those differences under the headings of:frequency and temporal pattern;intensity discrimination;spatial separation;and mechanisms for the reduction of self-generated *** systematically cover the issues of signal and noise in lateral-line systems,but emphasize recent work on self-generated noise,and signal and noise issues related to prey search strategies and collision avoidance.

关键词： behavior lateral line mechanoreception noise physiology signal.

INVERSE BORN SERIES FOR ScALAR WAVES

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Journal of computational Mathematics 2012年第6期30卷 601-614页

作者： Kimberly Kilgore Shari Moskow john c. Schotland department of Mathematics Drexel University Philadelphia PA 19104 USA department of Mathematics University of Michigan Ann Arbor MI 48109 USA

We consider the inverse scattering problem for scalar waves. We analyze the conver- gence of the inverse Born series and study its use in numerical simulations for the case of a spherically-symmetric medium in two and... 详细信息

关键词： Inverse scattering.

complement:a global immunometabolic regulator in amyotrophic lateral sclerosis

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Neural Regeneration Research 2021年第6期16卷 1210-1211页

作者： Martin W.Lo john d.Lee School of Biomedical Sciences Faculty of MedicineThe University of QueenslandSt LuciaQueenslandAustralia

Recently,Mcdonald et al.(2020)proposed that complement causes a metabolic switch to lipid consumption in amyotrophic lateral sclerosis(ALS),which raises the possibility of complement as a global immunometabolic *** ALS,neuromuscular degeneration occurs concurrently with complement-mediated inflammation,glucose intolerance,and elevated lipid ***,complement is being increasingly recognized as a metabolic regulator that can induce insulin resistance and alter fuel source ***,the authors propose that chronic complement activation may be driving metabolic reprogramming in ALS,which has broad implications for the field of immunometabolism and would be the first mechanistic explanation of the“lipid switch”in ***,it suggests that complement can drive a global shift in resources during inflammation,in which glucose is redirected from peripheral tissues to immune cells to support their inflammatory actions.

关键词： inflammation metabolism elevated

Evolution of landscape in a piedmont section of Eastern Himalayan foothills along India-Bhutan border: A tectono-geomorphic perspective

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Journal of Mountain Science 2019年第12期16卷 2828-2843页

作者： chandreyee cHAKRABARTI GOSWAMI Prasun JANA john c WEBER department of Geology University of Calcutta35Ballygunge Circular RoadKolkata 700029India Geological Survey of India Northern RegionSector ELucknow 226024India department of Geology Grand Valley State University1 Campus DriveAllendaleMI 49401 USA

The present study area involves part of a deformed coalesced fan located along the Himalayan Frontal Thrust(HFT)on the east of river Tista near the India-Bhutan *** area is marked by two spectacular E-W trending south-sloping scarps namely the Matiali(ca.60 m)and chalsa(ca.90 m)Scarps and a north-sloping E-W trending Thaljhora(ca.80 m)*** work comprises of a comparative study of geomorphology and geologic history in the adjacent interfluves of Jaldhaka-Gathia and Neora-Murti rivers to understand the tectonic history of the *** mapped the Jaldhaka-Gathia river interfluve at a 1:25,000 scale and report a hitherto unidentified northerly sloping small scarp of ca.5 m height named the Nagrakata *** scarp was identified using satellite images,dEMs,and total station *** interpret that the two northsloping,E-W trending scarps(Thaljhora and Nagrakata Scarps)are manifestations of steep limbs of anticlines over blind south-dipping back *** they form a wrinkle-ridge pair behind the north-dipping HFT,which is manifested by south-sloping chalsa *** propose a plausible geomorphic model interpreting that deformation along the small fan in the Jaldhaka-Gathia interfluves is younger compared to fan deposition and deformation in the adjacent Mal-Murti *** most recent geomorphology of the Jaldhaka-Gathia interfluve is controlled by tectonism associated with the thrust below the Nagrakata Scarp where the youngest deformation episode is recorded to at around^6 ka and is likely related to motion on a splay off of the thrust beneath the Thaljhora Scarp.

关键词： Eastern Himalayas Thaljhora Scarp Nagrakata Scarp drainage Back-thrust Wrinkle-ridge

continued development of azithromycin as a neuroprotective therapeutic for the treatment of spinal cord injury and other neurological conditions

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Neural Regeneration Research 2021年第3期16卷 508-509页

作者： Timothy J.Kopper john c.Gensel Spinal cord and Brain Injury Research center Department of PhysiologyUniversity of KentuckyLexingtonKYUSA

Spinal cord injury(ScI)induces a robust inflammatory response largely mediated by resident microglia and infiltrating macrophages across the blood-brain *** these cell populations are capable of promoting repair and regenerative responses,in the days and weeks after ScI they predominately adopt pro-inflammatory profiles known to inhibit recovery and potentiate secondary injury pathways.

关键词： protective injury therapeutic

Proportional-integral-derivative control of nonlinear half-car electro-hydraulic suspension systems

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浙江大学学报（英文版）A辑：应用物理与工程 2013年第6期14卷 401-416页

作者： john E. d. EKORU Jimoh O. PEdRO School of Mechanical Aeronautical and Industrial Engineering University of the Witwatersrand Private Bag 03 WITS 2050 Johannesburg South Africa

This paper presents the development of a proportional-integral-derivative (PId)-based control method for application to active vehicle suspension systems (AVSS). This method uses an inner PId hydraulic actuator force control loop, in combination with an outer PId suspension travel control loop, to control a nonlinear half-car AVSS. Robustness to model uncertainty in the form of variation in suspension damping is tested, comparing performance of the AVSS with a passive vehicle suspension system (PVSS), with similar model parameters. Spectral analysis of suspension system model output data, obtained by performing a road input disturbance frequency sweep, provides frequency response plots for both nonlinear vehicle suspension systems and time domain vehicle responses to a sinusoidal road input disturbance on a smooth road. The results show the greater robustness of the AVSS over the PVSS to parametric uncertainty in the frequency and time domains.

关键词： Force control Proportional-integral-derivative (PId) control Nonlinear half-car Active vehicle suspension system (AVSS) Hydraulic actuator dynamics Model uncertainty