In vivo monitoring of tissue regeneration using a ratiometric lysosomal AIE probe

We used the 500-bpXenopusef1-α promoter and the 2-kb zebrafish histone2A.F/Zpromoter to generate several independent transgenic zebrafish lines expressing EGFP. While both promoters drive ubiquitous EGFP expression in early zebrafish development, they are systematically silenced in several adult tissues, including the retina and caudal fin. However, EGFP expression is temporarily renewed in the adult during either caudal fin or retinal regeneration. In the Tg(H2A.F/Z:EGFP)ntline, EGFP is moderately expressed in both the wound epithelium and blastema of the regenerating caudal fin. In the Tg(ef1-α:EGFP)ntline, EGFP expression is reinitiated and restricted to the blastema of the regenerating caudal fin and colabels with BrdU, PCNA, andmsxc-positive cells. Thus, these two ubiquitous promoters drive EGFP transgene expression in different cell populations during caudal fin regeneration. We further analyzed the ability of theef1-α:EGFPtransgene to label nonterminally differentiated cells during adult tissue regeneration. First, we demonstrated that the transgene is highly methylated in adult zebrafish caudal fin tissue, but not during fin regeneration, implicating methylation as a potential means of transgene silencing in this line. Next, we determined that theef1-α:EGFPtransgene is also re-expressed during adult retinal regeneration. Specifically, theef1-α:EGFPtransgene colabels with PCNA in the Müglia, a specialized cell that is the source of neuronal progenitors during zebrafish retinal regeneration. Thus, we concluded that Tg(ef1-α:EGFP)nt line visually marks nonterminally differentiated cells in multiple adult regeneration environments and may prove to be a useful marker in tissue regeneration studies in zebrafish.

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Dynamics of intravital concentration of amino acid metabolites in human brain in post-traumatic period

Доклады Академии наук ◽

10.31857/s0869-56524842238-242 ◽

2019 ◽

Vol 484 (2) ◽

pp. 238-242

Author(s):

N. A. Semenova ◽

P. E. Menshchikov ◽

A. V. Manzhurtsev ◽

M. V. Ublinskiy ◽

T. A. Akhadov ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Amino Acid ◽

Human Brain ◽

Leading Role ◽

Acid Metabolites ◽

Post Traumatic ◽

First Time

Intracellular concentrations of N acetyaspartate (NAA), aspartate (Asp) and glutamate (Glu) were determined for the first time in human brain in vivo, and the effect of severe traumatic brain injury on NAA synthesis in acute and late post-traumatic period was investigated. In MRI‑negative frontal lobes one day after injury Asp and Glu levels were found to decrease by 45 and 35%, respectively, while NAA level decreased by only 16%. A negative correlation between NAA concentration and the ratio of Asp/Glu concentrations was found. In the long-term period, Glu level returned to normal, Asp level remained below normal by 60%, NAA level was reduced by 65% relative to normal, and Asp/Glu ratio significantly decreased. The obtained results revealed leading role of the neuronal aspartate-malate shuttle in violation of NAA synthesis.

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In Vivo Monitoring of Osseointegration

ASME 2007 2nd Frontiers in Biomedical Devices ◽

10.1115/biomed2007-38078 ◽

2007 ◽

Author(s):

Lindsey R. VanSchoiack ◽

Veronica I. Shubayev ◽

Robert R. Myers ◽

James C. Earthman

Keyword(s):

Fibrous Tissue ◽

Tissue Formation ◽

Surgical Implant ◽

In Vivo Monitoring

The process of osseointegration is the firm anchoring of a surgical implant by the growth of bone around it without fibrous tissue formation at the interface. This process is critical for long-term implant success. The ability to monitor this process in vivo would allow for personalization of loading protocols to increase the rate of implant success overall by ensuring that implants are not over or under loaded during recovery. Accordingly, there is a strong need for an instrument that has the sensitivity to noninvasively measure osseointegration in vivo. One of the objectives of the present study was to assess the performance of an instrumented percussion probe for quantitatively monitoring the osseointegration process.

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Latent Antigen Vaccination in a Model Gammaherpesvirus Infection

Journal of Virology ◽

10.1128/jvi.75.17.8283-8288.2001 ◽

2001 ◽

Vol 75 (17) ◽

pp. 8283-8288 ◽

Cited By ~ 66

Author(s):

Edward J. Usherwood ◽

Kimberley A. Ward ◽

Marcia A. Blackman ◽

James P. Stewart ◽

David L. Woodland

Keyword(s):

Latent Infection ◽

Model Systems ◽

Murine Gammaherpesvirus ◽

Latently Infected ◽

Associated Proteins ◽

Infected Cells ◽

The Impact ◽

First Time

ABSTRACT Vaccines that can reduce the load of latent gammaherpesvirus infections are eagerly sought. One attractive strategy is vaccination against latency-associated proteins, which may increase the efficiency with which T cells recognize and eliminate latently infected cells. However, due to the lack of tractable animal model systems, the effect of latent-antigen vaccination on gammaherpesvirus latency is not known. Here we use the murine gammaherpesvirus model to investigate the impact of vaccination with the latency-associated M2 antigen. As expected, vaccination had no effect on the acute lung infection. However, there was a significant reduction in the load of latently infected cells in the initial stages of the latent infection, when M2 is expressed. These data show for the first time that latent-antigen vaccination can reduce the level of latency in vivo and suggest that vaccination strategies involving other latent antigens may ultimately be successfully used to reduce the long-term latent infection.

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Long‐term in vivo monitoring of transcription factor (TF) activation in cardiovascular (CV) control regions of mouse brain using bioluminescence imaging (BLI)

The FASEB Journal ◽

10.1096/fasebj.21.6.a1412-a ◽

2007 ◽

Vol 21 (6) ◽

Author(s):

David W Infanger ◽

Jeffrey R Peterson ◽

Ram V Sharma ◽

Robin L Davisson

Keyword(s):

Transcription Factor ◽

Mouse Brain ◽

Bioluminescence Imaging ◽

In Vivo Monitoring ◽

Control Regions

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The horse as a model for translational orthopedic research: examples of studies on the regeneration of cartilage and bone conducted in Costa Rica

Revista Ciencias Veterinarias ◽

10.15359/rcv.37-3.2 ◽

2019 ◽

Vol 37 (3) ◽

pp. 9-10

Author(s):

Rafael Vindas Bolaños ◽

Jos Malda ◽

René Van Weeren ◽

Janny De Grauw

Keyword(s):

Bone Defects ◽

Chondral Defects ◽

Fixation Techniques ◽

Equine Studies ◽

First Time ◽

Adhesive Capacity ◽

Stimulation Of ◽

Long Term Studies

The paper provides results published or to be published of long-term in vivo equine studies to evaluate techniques of possible regenerative matrices of cartilage and bone, by means of cell-free implants or stimulation of the bone marrow. From the fixation techniques analyzed, it can be concluded that the best alternatives are the pressure technique for subchondral defects and a novel hydrogel with self-adhesive capacity for chondral defects. The equine coxal tuberosity was used for the first time as a model for regeneration studies of bone defects, analyzing scaffolds based on tricalcium phosphate, polymers and nanoparticles, by means of 3-D printing. Osteoconductivity, osteoinductivity, and the importance of microporosity were documented.Given that decellularized materials do not always give significant desired results in the regeneration of cartilage, it is important to conduct long-term studies. The technique of nanofracture and a novel self-adhesive hydrogel in the knee of the equine showed promising preliminary results in the regeneration of cartilage.The knee and the coxal tuberosity of the horse represent models of studying cartilage and bone regeneration in a true translational sense as a source of highly valuable information for clinical studies, for both horses and humans.

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Intrinsic Cell-type Selectivity and Inter-neuronal Connectivity Alteration by Transcranial Focused Ultrasound

10.1101/576066 ◽

2019 ◽

Cited By ~ 3

Author(s):

Kai Yu ◽

Xiaodan Niu ◽

Esther Krook-Magnuson ◽

Bin He

Keyword(s):

Focused Ultrasound ◽

Inhibitory Neurons ◽

Synaptic Connectivity ◽

Fast Spiking ◽

First Time ◽

Transcranial Focused Ultrasound ◽

Specific Neuron ◽

Ultrasound Pulse

ABSTRACTTranscranial focused ultrasound (tFUS) is a promising neuromodulation technique, but its mechanisms remain unclear. We investigate the effect of tFUS stimulation on different neuron types and synaptic connectivity in in vivo anesthetized rodent brains. Single units were separated into regular-spiking and fast-spiking units based on their extracellular spike shapes, further validated in transgenic optogenetic mice models of light-excitable excitatory and inhibitory neurons. For the first time, we show that excitatory neurons are significantly less responsive to low ultrasound pulse repetition frequencies (UPRFs), whereas the spike rates of inhibitory neurons do not change significantly across all UPRF levels. Our results suggest that we can preferentially target specific neuron types noninvasively by altering the tFUS UPRF. We also report in vivo observation of long-term synaptic connectivity changes induced by noninvasive tFUS in rats. This finding suggests tFUS can be used to encode temporally dependent stimulation paradigms into neural circuits and non-invasively elicit long-term changes in synaptic connectivity.

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Establishment and Characterization of Human Germline Stem Cell Line with Unlimited Proliferation Potentials and no Tumor Formation

Scientific Reports ◽

10.1038/srep16922 ◽

2015 ◽

Vol 5 (1) ◽

Cited By ~ 19

Author(s):

Jingmei Hou ◽

Minghui Niu ◽

Linhong Liu ◽

Zijue Zhu ◽

Xiaobo Wang ◽

...

Keyword(s):

Cell Line ◽

T Antigen ◽

Tumor Formation ◽

Germline Stem Cell ◽

Sv40 Large T Antigen ◽

Western Blots ◽

Transplantation Assay ◽

First Time

Abstract Spermatogonial stem cells (SSCs) have significant applications in both reproductive and regenerative medicine. However, primary human SSCs are very rare and a human SSC line has not yet been available. In this study, we have for the first time reported a stable human SSC line by stably expressing human SV40 large T antigen. RT-PCR, immunocytochemistry and Western blots revealed that this cell line was positive for a number of human spermatogonial and SSC hallmarks, including VASA, DAZL, MAGEA4, GFRA1, RET, UCHL1, GPR125, PLZF and THY1, suggesting that these cells are human SSCs phenotypically. Proliferation analysis showed that the cell line could be expanded with significant increases of cells for 1.5 years and high levels of PCNA, UCHL1 and SV40 were maintained for long-term culture. Transplantation assay indicated that human SSC line was able to colonize and proliferate in vivo in the recipient mice. Neither Y chromosome microdeletions of numerous genes nor tumor formation was observed in human SSC line although there was abnormal karyotype in this cell line. Collectively, we have established a human SSC line with unlimited proliferation potentials and no tumorgenesis, which could provide an abundant source of human SSCs for their mechanistic studies and translational medicine.

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