Silk-based nerve guidance conduits with macroscopic holes modulate the vascularization of regenerating rat sciatic nerve

Peripheral nerve injuries induce a severe motor and sensory deficit. Since the availability of autologous nerve transplants for nerve repair is very limited, alternative treatment strategies are sought, including the use of tubular nerve guidance conduits(tNGCs). However, the use of tNGCs results in poor functional recovery and central necrosis of the regenerating tissue, which limits their application to short nerve lesion defects(typically shorter than 3 cm). Given the importance of vascularization in nerve regeneration, we hypothesized that enabling the growth of blood vessels from the surrounding tissue into the regenerating nerve within the tNGC would help eliminate necrotic processes and lead to improved regeneration. In this study, we reported the application of macroscopic holes into the tubular walls of silk-based tNGCs and compared the various features of these improved silk^(+) tNGCs with the tubes without holes(silk^(–) tNGCs) and autologous nerve transplants in an 8-mm sciatic nerve defect in rats. Using a combination of micro-computed tomography and histological analyses, we were able to prove that the use of silk^(+) tNGCs induced the growth of blood vessels from the adjacent tissue to the intraluminal neovascular formation. A significantly higher number of blood vessels in the silk^(+) group was found compared with autologous nerve transplants and silk^(–), accompanied by improved axon regeneration at the distal coaptation point compared with the silk^(–) tNGCs at 7 weeks postoperatively. In the 15-mm(critical size) sciatic nerve defect model, we again observed a distinct ingrowth of blood vessels through the tubular walls of silk^(+) tNGCs, but without improved functional recovery at 12 weeks postoperatively. Our data proves that macroporous tNGCs increase the vascular supply of regenerating nerves and facilitate improved axonal regeneration in a short-defect model but not in a critical-size defect model. This study suggests that further optimization of the macroscopic holes silk^(+) tNGC approach containing macroscopic holes might result in improved grafting technology suitable for future clinical use.

Regenerating gene 4 promotes chemoresistance of colorectal cancer by affecting lipid droplet synthesis and assembly

BACKGROUND Regenerating gene 4(REG4)has been proved to be carcinogenic in some cancers,but its manifestation and possible carcinogenic mechanisms in colorectal cancer(CRC)have not yet been elucidated.Our previous study found that the drug resistance of CRC cells may be closely linked to their fat metabolism.AIM To explore the role of REG4 in CRC and its association with lipid droplet formation and chemoresistance.METHODS We conducted a meta-analysis and bioinformatics and pathological analyses of REG4 expression in CRC.The effects of REG4 on the phenotypes and related protein expression were also investigated in CRC cells.We detected the impacts of REG4 on the chemoresistance and lipid droplet formation in CRC cells.Finally,we analyzed how REG4 regulated the transcription and proteasomal degradation of lipogenic enzymes in CRC cells.RESULTS Compared to normal mucosa,REG4 mRNA expression was high in CRC(P<0.05)but protein expression was low.An inverse correlation existed between lymph node and distant metastases,tumor-node-metastasis staging or short overall survival and REG4 mRNA overexpression(P<0.05),but vice versa for REG4 protein expression.REG4-related genes included:Chemokine activity;taste receptors;protein-DNA and DNA packing complexes;nucleosomes and chromatin;generation of second messenger molecules;programmed cell death signals;epigenetic regulation and DNA methylation;transcription repression and activation by DNA binding;insulin signaling pathway;sugar metabolism and transfer;and neurotransmitter receptors(P<0.05).REG4 exposure or overexpression promoted proliferation,antiapoptosis,migration,and invasion of DLD-1 cells in an autocrine or paracrine manner by activating the epidermal growth factor receptor-phosphoinositide 3-kinase-Akt-nuclear factor-κB pathway.REG4 was involved in chemoresistance not through de novo lipogenesis,but lipid droplet assembly.REG4 inhibited the transcription of acetyl-CoA carboxylase 1(ACC1)and ATP-citrate lyase(ACLY)by disassociating the complex formation of anti-acetyl(AC)-acetyl-histone 3-AC-histone 4-inhibitor of growth protein-5-si histone deacetylase;-sterol-regulatory element binding protein 1 in their promoters and induced proteasomal degradation of ACC1 or ACLY.CONCLUSION REG4 may be involved in chemoresistance through lipid droplet assembly.REG4 reduces expression of de novo lipid synthesis key enzymes by inhibiting transcription and promoting ubiquitination-mediated proteasomal degradation.

Jonzac Thermal Spring Water Reinforces Skin Barrier Function of Human Skin and Presents a Soothing and Regenerating Effect

The skin is a formidable physical and biological barrier which communicates continuously with the outside of the body. And the stratum corneum, the outermost layer of human epidermis, plays a central role in the interaction between the cutaneous tissue and the external environment. The horny layer, and more generally the whole skin layers, avoid the penetration of harmful exogenous agents, produce molecules named anti-microbial peptides which impact the composition of the cutaneous microbiota, regulate the internal corporal temperature, avoid the water loss from the inside of the body and constitute an incredible efficient anti-oxidant network. Nevertheless, nowadays, the skin is more and more solicited by the different elements of the cutaneous exposome, including atmospheric pollution and solar radiations, which can cause a dramatic acceleration of the skin ageing process. As a consequence, due to the multifunctional protective role of the skin, during the recent decade the cosmetic industry invested massively in the development of new raw materials and end-products (dermo-cosmetics) able to preserve an optimal state of the skin regarding the external environment. Based on their physical-chemical properties thermal spring waters, which are extremely rich in inorganics ions, are interesting and powerful candidates to be part, as integral component, of new efficient dermo-cosmetic formulations dedicated to protect the skin from the external stimuli. The aim of the present work was to investigate and characterize the activity of Jonzac thermal spring water on the skin. Using different models, we proved for the first time that Jonzac thermal spring water reinforces the barrier function of the skin by modulating the expression of key markers including filaggrin and human beta defensin 2 on ex vivo human skin. The ex vivo and in vivo hydration activity, by Raman spectroscopy and corneometry respectively, has been also demonstrated. We have also shown that Jonzac thermal spring water ameliorates significantly the cutaneous microrelief in vivo. To conclude, we characterize the soothing effect of Jonzac thermal spring water by the analysis of histamine release in Substance P treated skin explants and by measuring the redness of the skin following UV exposure of the skin in vivo. We observed that both parameters decreased following a preventive treatment of the skin with Jonzac thermal spring water. Taken together our results indicate that Jonzac thermal spring water is a promising and powerful dermo-cosmetic which can be used to preserve an optimal state of the cutaneous tissue.

Locally Minimum Storage Regenerating Codes in Distributed Cloud Storage Systems

In distributed cloud storage systems, inevitably there exist multiple node failures at the same time. The existing methods of regenerating codes, including minimum storage regenerating(MSR) codes and minimum bandwidth regenerating(MBR) codes, are mainly to repair one single or several failed nodes, unable to meet the repair need of distributed cloud storage systems. In this paper, we present locally minimum storage regenerating(LMSR) codes to recover multiple failed nodes at the same time. Specifically, the nodes in distributed cloud storage systems are divided into multiple local groups, and in each local group(4, 2) or(5, 3) MSR codes are constructed. Moreover, the grouping method of storage nodes and the repairing process of failed nodes in local groups are studied. Theoretical analysis shows that LMSR codes can achieve the same storage overhead as MSR codes. Furthermore, we verify by means of simulation that, compared with MSR codes, LMSR codes can reduce the repair bandwidth and disk I/O overhead effectively.

Serotonin controls axon and neuronal regeneration in the nervous system:lessons from regenerating animal models

Traumatic brain injury （TBI） is a mechanical injury to brain tissue that leads to an impairment of function and a broad spectrum of symptoms and disabilities; often, it is followed by diffuse axonal injury, which causes denaturation of the white matter and axon retraction, leaving patients with severe brain damage or even in a persistent vegetative state.

Role of regenerating islet-derived proteins in inflammatory bowel disease

Inflammatory bowel disease(IBD)is an inflammatory disorder of the gastrointestinal tract that affects millions of patients worldwide.It has a complex and multifactorial etiology leading to excessive exposure of intestinal epithelium to microbial antigens,inappropriate activation of the immune system and ultimately to the damage of intestinal tissues.Although numerous efforts have been made to improve the disease management,IBD remains persistently recurring and beyond cure.This is due largely to the gaps in our understanding of the pathogenesis of IBD that hamper the development of timely diagnoses and effective treatment.However,some recent discoveries,including the beneficial effects of interleukin-22(IL-22)on the inflamed intestine,have shed light on a self-protective mechanism in IBD.Regenerating islet-derived(REG/Reg)proteins are small secretory proteins which function as IL-22’s downstream effectors.Mounting studies have demonstrated that IBD patients have significantly increased REG expressions in the injured intestine,but with undefined mechanisms and roles.The reported functions of REG/Reg proteins in intestinal homeostasis,such as those of antibacterial,anti-inflammatory and tissue repair,lead us to discuss their potential mechanisms and clinical relevance in IBD in order to advance IBD research and management.

DESIGN OF EXACT REGENERATING HIERARCHICAL CODE FOR DISTRIBUTED STORAGE SYSTEM

Erasure code is widely used as the redundancy scheme in distributed storage system. When a storage node fails, the repair process often requires to transfer a large amount of data. Regenerating code and hierarchical code are two classes of codes proposed to reduce the repair bandwidth cost. Regenerating codes reduce the amount of data transferred by each helping node, while hierarchical codes reduce the number of nodes participating in the repair process. In this paper, we propose a "sub-code nesting framework" to combine them together. The resulting regenerating hierarchical code has low repair degree as hierarchical code and lower repair cost than hierarchical code. Our code can achieve exact regeneration of the failed node, and has the additional property of low updating complexity.

Corneal matrix repair therapy with the regenerating agentin neurotrophic persistent epithelial defects

Citation： Utine CA, Engin Durmaz C, Koqak N. Corneal matrix repair therapy with the regenerating agent in neurotrophic persistent epithelial defects, lntJOphthalmo12017;10（12）：1935-1939

Immunodetection of ephrin receptors in the regenerating tail of the lizard Podarcis muralis suggests stimulation of differentiation and muscle segmentation

Ephrin receptors are the most common tyrosine kinase effectors operating during development. Ephrin receptor genes are reported to be up-regulated in the regenerating tail of the Podarcis muralis lizard. Thus, in the current study, we investigated immunolocalization of ephrin receptors in the Podarcis muralis tail during regeneration. Weak immunolabelled bands for ephrin receptors were detected at 15–17 kDa, with a stronger band also detected at 60–65 kDa. Labelled cells and nuclei were seen in the basal layer of the apical wound epidermis and ependyma, two key tissues stimulating tail regeneration. Strong nuclear and cytoplasmic labelling were present in the segmental muscles of the regenerating tail, sparse blood vessels, and perichondrium of regenerating cartilage. The immunolocalization of ephrin receptors in muscle that gives rise to large portions of new tail tissue was correlated with their segmentation. This study suggests that the high localization of ephrin receptors in differentiating epidermis, ependyma, muscle, and cartilaginous cells is connected to the regulation of cell proliferation through the activation of programs for cell differentiation in the proximal regions of the regenerating tail. The lower immunolabelling of ephrin receptors in the apical blastema, where signaling proteins stimulating cell proliferation are instead present, helps maintain the continuous growth of this region.

COMPARATIVE STUDY OF PHOSPHOTYROSYL PROTEIN PHOSPHATASE OF MICE NORMAL LIVER, REGENERATING LIVER, AND MICE H22A HEPATOMA ASCITES CELL

In regenerating liver of mice, marked increase of the activity of phosphotyrosyl protein phosphatase (PTPP) in cytosol was observed. The PTPP activity varied with time and reached the highest level between 24 to 48 hours after partial hepatectomy. In H22a cells the PTPP activity found in every subcellular fraction was lower than that of the normal liver. The PTPP activity was mostly concentrated in lysosomes of normal liver, but mainly distributed in nucleus, cytosol and microsome of regenerating liver. In H22a cells PTPP activity seemed distribute evenly. Five similar major PTPP peaks (I-V) were obtained on DEAE cellulose chromatography of cytosols from all three of liver cells studied. However, two additional PTPP peaks, a and b, were also obtained from cytosol of liver.

The emerging roles of transplanted radial glial cells in regenerating the central nervous system

Scientists conclude that a combination of treatments involving rehabilitation,drug delivery,surgery and cell transplantation are necessary to achieve significant progress in regenerating the injured central nervous system（CNS）.

Morphogenetic Action of Neurotransmitters on Regenerating Planarians—A Review

Planarians can be used as invertebrate bioassays to evaluate the role of neurotransmitters on regenerating cells. The influence of the nervous system is crucial to regenerate a normal complete animal. The neurotrophic action of the nervous system has been attributed to the major neurohormones present throughout the animal kingdom. The same type of transmitters found in mammals have been extensively found in many invertebrates, including planarians, but their role in regeneration is unclear. Neurotransmitters and drugs which act on neurohumoral transmission have been used to determine the role of each neurohormonc on regenerating planarians. Biochemical and pharmacological mechanisms of neurohormones on regenerative planarians are reviewed, as is their putative role on regeneration. Correlations with the roles of neurotransmitters in the central nervous system of higher organisms are also addressed.

Huu S. TIEU Request for FDA to Establish Regenerating Human Cells as Law on December 13, 2016 President Barack H. Obama Signed the 21st Century CURES Act into FDA Regulation and Law

Background and Aims: On November 24, 2009, Huu S. TIEU and Golden Sunrise Pharmaceutical, Inc. (Golden Sunrise) applied for the Technology and Innovation to be reviewed and evaluated by the U.S. Food and Drug Administration (FDA). In the review and evaluation, it was requested by Golden Sunrise designated the new indications for this application under Serious or Life-threatening conditions or diseases. Discussions followed with the FDA, Huu S. TIEU, and Golden Sunrise for FDA approval on new products and new indications on existing new Medical Technology and Innovation. It was agreed in Year-2015 that the FDA would take the request for new indications to the United States Congress to establish into FDA regulation and law. At that time the following was the FDA Guidance—“Emergency Use of a Test Article” is exempt from prior Institutional Review Board or Advisory Committee evaluation and approval, provided that such emergency use is reported to the Institutional Review Board within five working days after use. Expedited Institutional Review Board or Advisory Committee approval is not permitted in emergency use. There has been no funding to the authors for the writing or publication of this article. Methods: It was requested by Huu S. TIEU and Golden Sunrise in documents given to the FDA to have Serious or Life-threatening conditions or diseases indication be recognized by law. On August 08, 2015, the FDA responding to this request took the documentation produced by Golden Sunrise to the United States Congress on behalf of Golden Sunrise and Huu S. TIEU. This article encompasses the FDA regulatory method as well as the discussion and results of the establishment of the FDA and the 21st Century Cures Act. Results: On December 13, 2016, H.R.34—114th United States Congress (2015-2016) 21st Century CURES Act was signed into law by President Barack H. Obama which included the Serious or Life-threatening indication to be written into the CURES Act. In summary, the 21st Century Cures Act is a landmark piece of legislation that enjoyed broad bipartisan support in United States Congress. The main goals of the Act are impactful and should transform future cancer, neurologic, and precision medicine or drug research as well as aid individuals with mental health is intended to facilitate the prompt approval of new agents and devices, clinicians should be aware of the types of data behind an approval and take this into consideration when developing illnesses and opioid dependence. However, some of the wording within the CURES Act regarding the drug and device approval process may bring pause to health care providers including pharmacists. Although this wording and implementing care plans and counseling patients. The 21st Century Cures Act was incorporated into laws and regulations by the FDA under § 3072 of the Act grants the Commissioner of Food and Drugs the authority to appoint and set the annual rate of pay for outstanding and qualified candidates to scientific, technical, or professional positions that support the development, review, and regulation of medical products.

Glial scar size, inhibitor concentration, and growth of regenerating axons after spinal cord transection

A mathematical model has been formulated in accordance with cell chemotaxis and relevant experimental data. A three-dimensional lattice Boltzmann method was used for numerical simulation. The present study observed the effects of glial scar size and inhibitor concentration on regenerative axonal growth following spinal cord transection. The simulation test comprised two parts： （1） when release rates of growth inhibitor and promoter were constant, the effects of glial scar size on axonal growth rate were analyzed, and concentrations of inhibitor and promoters located at the moving growth cones were recorded. （2） When the glial scar size was constant, the effects of inhibitor and promoter release rates on axonal growth rate were analyzed, and inhibitor and promoter concentrations at the moving growth cones were recorded. Results demonstrated that （1） a larger glial scar and a higher release rate of inhibitor resulted in a reduced axonal growth rate. （2） The axonal growth rate depended on the ratio of inhibitor to promoter concentrations at the growth cones. When the average ratio was 〈 1.5, regenerating axons were able to grow and successfully contact target cells.

Molecular complexity of visual mapping: a challenge for regenerating therapy

Investigating the cellular and molecular mechanisms involved in the development of topographically ordered connections in the central nervous system constitutes an important issue in neurobiology because these connections are the base of the central nervous system normal function.The dominant model to study the development of topographic maps is the projection from the retinal ganglion cells to the optic tectum/colliculus.The expression pattern of Eph/ephrin system in opposing gradients both in the retina and the tectum,labels the local addresses on the target and gives specific sensitivities to growth cones according to their topographic origin in the retina.The rigid precision of normal retinotopic mapping has prompted the chemoaffinity hypothesis,positing axonal targeting to be based on fixed biochemical affinities between fibers and targets.However,several lines of evidence have shown that the mapping can adjust to experimentally modified targets with flexibility,demonstrating the robustness of the guidance process.Here we discuss the complex ways the Ephs and ephrins interact allowing to understand how the retinotectal mapping is a precise but also a flexible process.

Brazilian savanna re-establishment in a monoculture forest:diversity and environmental relations of native regenerating understory in Pinus caribaea Morelet. stands

In this paper we analyze and compare natural regeneration in shrub-tree community in three areas below Pinus caribaea stands and a natural area （cerrado sensu stricto）. We also analyze the influence of biophysical and environmental variables on the distribution of regenerating shrub-tree species. The areas were analyzed and compared in relation to dispersal syndromes as well, being zoochory and anemochory the prevailing syndroms in the four areas. The sites below P. caribaea show a heterogeneous regen- eration with the number of species ranging from 18 to 42. We analyzed the influence of the biophysical and envi- ronmental variables performing a canonical correspon- dence analyses, being found significant values for variables distance from remnant and basal area. The species Si- paruna guianensis, Miconia albicans, Xylopia aromatica, Sclerolobium paniculatum, Casearia sylvestris and P. caribaea were the most importante ones in the four areas,

Functional trait profiles and diversity of trees regenerating in disturbed tropical forests and agroforests in Indonesia

A main question in restoration of degraded forests and forest landscapes recovering from logging and fire is what to expect from natural regeneration through surviving propagules in the soil or seed sources and associated dispersal agents from the surrounding landscape mosaic,as alternative to tree planting.Tree diversity in secondary forests may be high,but based on newcomer species of low wood density and long-distance,abiotic dispersal modes.We compiled and analyzed three pairs of case studies(totaling 815 plots and 11.8 ha)of secondary forests recovering from logging,fire and conversion to agroforest in Sumatra and Kalimantan(Indonesia)on mineral soils.Data on tree species diversity,wood density frequency distribution(indicative of successional status)and dispersal modes were compared with those of less disturbed comparator forests in the same landscapes.Relatively undisturbed lowland dipterocarp forest in Kalimantan had close to 200 species of trees(>10 cm diameter)at a 1-ha sample scale(and 450 at a 10-ha scale).After repeated fires a sample area of 2 ha was needed to reach the same species richness.Regulation-based logging had little impact on tree species richness.In rubber agroforest with low-intensity management beyond rubber planting,50 tree species were found at a 1-ha scale and close to 100 species in 3 ha.The Kalimantan forest after repeated fires had a markedly higher fraction of lowwood-density trees(40%),but otherwise,all forests sampled were similar in overall wood density profiles.Selectively logged forest managed by a local community(village forest)and rubber agroforest in Sumatra contained larger fractions of heavy-wood-density trees.The majority of trees(50%–70%)had birds,bats and primates as dispersal agents in all sites.Selectively logged forests had higher fractions of autochorous species(15%)compared to other sites.Anemochorous(wind-dispersed)species,especially Macaranga lowii,were most common(20%)in lowland dipterocarp forest.Comparison between secondary forests and agroforests showed the influence of farmer selection regarding what is allowed to grow beyond the pole stage.Wood density and seed dispersal profiles can be used as degradation indicators of species assemblages across various disturbance levels and types,as they reflect the habitat quality of the surrounding landscape mosaics.

Time course analysis of sensory axon regeneration in vivo by directly tracing regenerating axons

Most current studies quantify axon regeneration by immunostaining regeneration-associated proteins,representing indirect measurement of axon lengths from both sensory neurons in the dorsal root ganglia and motor neurons in the spinal cord.Our recently developed method of in vivo electroporation of plasmid DNA encoding for enhanced green fluorescent protein into adult sensory neurons in the dorsal root ganglia provides a way to directly and specifically measure regenerating sensory axon lengths in whole-mount nerves.A mouse model of sciatic nerve compression was established by squeezing the sciatic nerve with tweezers.Plasmid DNA carrying enhanced green fluorescent protein was transfected by ipsilateral dorsal root ganglion electroporation 2 or 3 days before injury.Fluorescence distribution of dorsal root or sciatic nerve was observed by confocal microscopy.At 12 and 18 hours,and 1,2,3,4,5,and 6 days of injury,lengths of regenerated axons after sciatic nerve compression were measured using green fluorescence images.Apoptosis-related protein caspase-3 expression in dorsal root ganglia was determined by western blot assay.We found that in vivo electroporation did not affect caspase-3 expression in dorsal root ganglia.Dorsal root ganglia and sciatic nerves were successfully removed and subjected to a rapid tissue clearing technique.Neuronal soma in dorsal root ganglia expressing enhanced green fluorescent protein or fluorescent dye-labeled microRNAs were imaged after tissue clearing.The results facilitate direct time course analysis of peripheral nerve axon regeneration.This study was approved by the Institutional Animal Care and Use Committee of Guilin Medical University,China(approval No.GLMC201503010)on March 7,2014.

Regenerating nerve fiber innervation of extraocular muscles and motor functional changes following oculomotor nerve injuries at different sites

In the present study, the oculomotor nerves were sectioned at the proximal （subtentorial） and distal （superior orbital fissure） ends and repaired. After 24 weeks, vestibulo-ocular reflex evaluation confirmed that the regenerating nerve fibers following oculomotor nerve injury in the superior orbital fissure had a high level of specificity for innervating extraocular muscles. The level of functional recovery of extraocular muscles in rats in the superior orbital fissure injury group was remarkably superior over that in rats undergoing oculomotor nerve injuries at the proximal end （subtentorium）. Horseradish peroxidase retrograde tracing through the right superior rectus muscle showed that the distribution of neurons in the nucleus of the oculomotor nerve was directly associated with the injury site, and that crude fibers were badly damaged. The closer the site of injury of the oculomotor nerve was to the extraocular muscle, the better the recovery of neurological function was. The mechanism may be associated with the aberrant number of regenerated nerve fibers passing through the injury site.

76nt RNAs are transported axonally into regenerating axons and growth cones.What are they doing there?

Successful nerve regeneration requires not only that neurons reconstruct new axons distal to the site of injury,but also those growing axons must navigate through the neuropil to make appropriate synaptic connections with target cells.While this is an imposing task for the thousands of axons that may occupy a regenerating nerve in the peripheral nervous system or a tract inthe central nervous system, the billions of neurons in the developing brain must accomplish similar tasks making connections that number in the trillions. How do neurons do this？