Regenerative Agent Research Articles

Effects of different gelling agents on the different stages of rice regeneration in two rice cultivars.

Plant tissue culture technology offers a solution for meeting the increasing commercial demand on economically important plants such as rice, a widespread dietary staple. However, significant genotype-specific morphogenetic responses constitute a considerable on rice regeneration in plant biotechnology contexts. Aside from genotype dependency, the components of the nutrient media including gelling agents have an important impact on regeneration efficiency. The current study explores the effect of different gelling agents on various stages of rice regeneration in two Egyptian rice cultivars-Sakha104 and Giza178. Media solidified with varying concentrations of a variety of gelling agents (agar, bacto agar, gelrite and phytagel) were tested for their impact on the frequency of callus induction, shoot regeneration and rooting. The results indicated gellan gum (gelrite and phytagel) was superior to agar products (agar and bacto agar) for callus induction. By contrast, no significant differences were found between different gelling agents for shoot regeneration. Gellan gum and media solidified with bacto agar were found to lead to significantly higher root regeneration than agar. The Sakha104 cultivar showed better responses than Giza 178 for callus induction and similar performance to the Giza 178 cultivar for root regeneration irrespective of the gelling agent. This work provides insights into the impact of different gelling agents on the morphogenetic response of two rice cultivars and can be used to help maximize the frequency of rice regeneration.

Dried bovine placenta improves spermatozoa count in a rat model of male reproductive aging.

Background and Aim:In the male reproductive system, the aging process can lead to infertility. Recently, placenta and its derivatives have been researched as regenerative agents. This study aimed to describe the basic components of dried bovine placenta powder and its potential effects as a regenerative agent in a rat model of male reproductive aging with D-galactose induction.Materials and Methods:We divided 15 male Wistar rats, 2 months of age, into three groups: A, the health control group; B, the D-galactose induction group, and C, the D-galactose induction and 10% dried bovine placenta supplementation group. We measured epididymal sperm concentration and testicular weight and volume and analyzed these using one-way analysis of variance.Results:Dried bovine placenta was rich in nutrients, with 61.98% protein, 21.25±2.07 carbohydrates, 8.58% water, 4.93% ash, and 3.27% fat. The mean epididymal spermatozoa concentration of the rats in Groups A, B, and C was 3026×106/mL, 1492.8×106/mL, and 2732.5×106/mL, respectively. The average total testicle weights were 2.44 g, 2.72 g, and 2.57 g, respectively. The average total testicle volumes were 2.29 cm3, 2.49 cm3, and 2.33cm3, respectively.Conclusion:Dried bovine placenta powder is rich in nutrients, especially protein. Supplementation with dried bovine placenta can improve epididymal spermatozoa concentration that is important in fertility.

Magnesium-based biomaterials as emerging agents for bone repair and regeneration: from mechanism to application

Magnesium (Mg) is the fourth most abundant element in the human body and is important in terms of specific osteogenesis functions. Here, we provide a comprehensive review of the use of magnesium-based biomaterials (MBs) in bone reconstruction. We review the history of MBs and their excellent biocompatibility, biodegradability and osteopromotive properties, highlighting them as candidates for a new generation of biodegradable orthopedic implants. In particular, the results reported in the field-specific literature (280 articles) in recent decades are dissected with respect to the extensive variety of MBs for orthopedic applications, including Mg/Mg alloys, bioglasses, bioceramics, and polymer materials. We also summarize the osteogenic mechanism of MBs, including a detailed section on the physiological process, namely, the enhanced osteogenesis, promotion of osteoblast adhesion and motility, immunomodulation, and enhanced angiogenesis. Moreover, the merits and limitations of current bone grafts and substitutes are compared. The objective of this review is to reveal the strong potential of MBs for their use as agents in bone repair and regeneration and to highlight issues that impede their clinical translation. Finally, the development and challenges of MBs for transplanted orthopedic materials are discussed.

Assessment of Durability Properties of Reclaimed Asphalt Pavement Using Two Rejuvenators: Waste Engine Oil and Asphalt Cement (60-70) Penetration Grade

The production of asphalt pavements using Reclaim Asphalt Pavement (RAP) has achieved economic and environmental benefits. However, one of the main challenges when using untreated RAP in pavement construction is the hardness of the binder due to aging. The purpose of this study is to recycle and restore damaged asphalt using two types of regenerative agents: Waste Engine Oil (WEO) and Asphalt Cement (AC (60-70)) Penetration Grade. Five ratios (1, 1.5, 2, 2.5 and 3) % of both types of regenerators were added to the RAP, separately, for the purpose of regeneration. Marshall Test was performed on the regenerated samples in order to obtain the optimum ratios for the regenerative additives, which will be adopted in subsequent tests, which include; indirect tensile strength (ITS), tensile strength Ratio (TSR) and Duple Punch Shear Strength Test (DPSST) to evaluate the performance of regenerated RAP mixes and compare them with the original RAP. The results indicated that (1.5 and 3) % are the optimal ratios for (WEO and AC (60-70)), respectively. In addition, the results of the performance tests indicated that the regenerated RAP mixes are better than the original RAP in terms of cracking resistance, stripping resistance and resistance to moisture damage, as well as achieving the specification requirements for the surface course. It can be concluded that rap recycling using (WEO and AC (60-70)) is an effective process that reduces paving costs, reduces environmental pollution and leads to gain sustainable paving.The first section in your paper

Applications of Mesenchymal Stem Cells in Skin Regeneration and Rejuvenation.

Mesenchymal stem cells (MSCs) are multipotent stem cells derived from adult stem cells. Primary MSCs can be obtained from diverse sources, including bone marrow, adipose tissue, and umbilical cord blood. Recently, MSCs have been recognized as therapeutic agents for skin regeneration and rejuvenation. The skin can be damaged by wounds, caused by cutting or breaking of the tissue, and burns. Moreover, skin aging is a process that occurs naturally but can be worsened by environmental pollution, exposure to ultraviolet radiation, alcohol consumption, tobacco use, and undernourishment. MSCs have healing capacities that can be applied in damaged and aged skin. In skin regeneration, MSCs increase cell proliferation and neovascularization, and decrease inflammation in skin injury lesions. In skin rejuvenation, MSCs lead to production of collagen and elastic fibers, inhibition of metalloproteinase activation, and promote protection from ultraviolet radiation-induced senescence. In this review, we focus on how MSCs and MSC-derived molecules improve diseased and aged skin. Additionally, we emphasize that induced pluripotent stem cell (iPSC)-derived MSCs are potentially advanced MSCs, which are suitable for cell therapy.

Hydroxyapatite sonosensitization of ultrasound-triggered, thermally responsive hydrogels: An on-demand delivery system for bone repair applications.

While bones have the innate capability to physiologically regenerate, in certain cases regeneration is suboptimal, too slow, or does not occur. Biomaterials-based growth factor delivery systems have shown potential for the treatment of challenging bone defects, however, achieving controlled growth factor release remains a challenge. The objective of this study was to develop a thermally responsive hydrogel for bone regeneration capable of ultrasound-triggered on-demand delivery of therapeutic agents. Furthermore, it was hypothesized that incorporation of hydroxyapatite (HA) into the hydrogel could increase sonosensitization, augmenting ultrasound sensitivity to enable controlled therapeutic release to the target tissue. Alginate thermally responsive P(Alg-g-NIPAAm) hydrogels were fabricated and varying quantities of HA (1, 3, 5, and 7% wt./vol.) incorporated. All hydrogels were highly injectable (maximum injection force below 6.5N) and rheological characterization demonstrated their ability to gel at body temperature. The study demonstrated the ultrasound-triggered release of sodium fluorescein (NaF), bovine serum albumin (BSA), and bone morphogenetic protein 2 (BMP-2) from the hydrogels. Release rates of BSA and BMP-2 were significantly enhanced in the HA containing hydrogels, confirming for the first time the role of HA as a son sensitizer. Together these results demonstrate the potential of these ultrasound-triggered thermally responsive hydrogels for on-demand delivery of therapeutic agents for bone regeneration.

Current and Advanced Nanomaterials in Dentistry as Regeneration Agents: An Update

Bentham Science - STM publisher of online and print journals, and related print/online book series. Bentham Science answers the information needs of scientists in the fields of pharmaceutical, biomedical, medical, engineering, technology, computer and social sciences.

Materials for peripheral nerve repair constructs: Natural proteins or synthetic polymers?

The efficacious repair of severe peripheral nerve injuries is currently an unmet clinical need, and biomaterial constructs offer a promising approach to help promote nerve regeneration. Current research focuses on the development of more sophisticated constructs with complex architecture and the addition of regenerative agents to encourage timely reinnervation and promote functional recovery. This review surveyed the present landscape of nerve repair construct literature with a focus on six selected materials that are frequently encountered in this application: the natural proteins collagen, chitosan, and silk, and the synthetic polymers poly-ε-caprolactone (PCL), poly-lactic-co-glycolic acid (PLGA) and poly-glycolic acid (PGA). This review also investigated the use of cell therapy in nerve repair constructs, and in all instances concentrated on publications reporting constructs developed and tested in vivo in the last five years (2015–2020). Across the selected literature, the popularity of natural proteins and synthetic polymers appears to be broadly equivalent, with a similar number of studies reporting successful outcomes in vivo. Both material types are also utilised as vehicles for cell therapy, which has much potential to improve the results of nerve bridging for treating longer gaps.

An Insight into the Role of Non-Porphyrinoid Photosensitizers for Skin Wound Healing.

The concept behind photodynamic therapy (PDT) is being successfully applied in different biomedical contexts such as cancer diseases, inactivation of microorganisms and, more recently, to improve wound healing and tissue regeneration. The effectiveness of PDT in skin treatments is associated with the role of reactive oxygen species (ROS) produced by a photosensitizer (PS), which acts as a “double agent”. The release of ROS must be high enough to prevent microbial growth and, simultaneously, to accelerate the immune system response by recruiting important regenerative agents to the wound site. The growing interest in this subject is reflected by the increasing number of studies concerning the optimization of relevant experimental parameters for wound healing via PDT, namely, light features, the structure and concentration of the PS, and the wound type and location. Considering the importance of developing PSs with suitable features for this emergent topic concerning skin wound healing, in this review, a special focus on the achievements attained for each PS class, namely, of the non-porphyrinoid type, is given.

Current and Advanced Nanomaterials in Dentistry as Regeneration Agents: An Update.

In modern dentistry, nanomaterials have strengthened their foothold among tissue engineering strategies for treating bone and dental defects due to a variety of reasons, including trauma and tumors. Besides their finest physiochemical features, the biomimetic characteristics of nanomaterials promote cell growth and stimulate tissue regeneration. The single units of these chemical substances are small-sized particles, usually between 1 to 100 nm, in an unbound state. This unbound state allows particles to constitute aggregates with one or more external dimensions and provide a high surface area. Nanomaterials have brought advances in regenerative dentistry from the laboratory to clinical practice. They are particularly used for creating novel biomimetic nanostructures for cell regeneration, targeted treatment, diagnostics, imaging, and the production of dental materials. In regenerative dentistry, nanostructured matrices and scaffolds help control cell differentiation better. Nanomaterials recapitulate the natural dental architecture and structure and form functional tissues better compared to the conventional autologous and allogenic tissues or alloplastic materials. The reason is that novel nanostructures provide an improved platform for supporting and regulating cell proliferation, differentiation, and migration. In restorative dentistry, nanomaterials are widely used in constructing nanocomposite resins, bonding agents, endodontic sealants, coating materials, and bioceramics. They are also used for making daily dental hygiene products such as mouth rinses. The present article classifies nanostructures and nanocarriers in addition to reviewing their design and applications for bone and dental regeneration.

Přehled přípravků k regeneraci bariérové funkce kůže

Přehled přípravků k regeneraci bariérové funkce kůže

The financialization of community development: the role of social finance

Abstract Local community organisations, many of which began life as agents of community self defence and regeneration during a Post-Fordist era of massive job losses in the 1970s and 1980s, are now being transposed into low-cost deliverers of public services in competition with the private sector. More recently, this process increasingly involves injections of “social finance” from external private sources. This article offers a brief history of how the voluntary and community sector has been corralled into a marketized and financialized role where the primacy of business management replaces community need. As in other spheres, there has been a paradigm shift from Keynesian demand management to a neoliberal perspective of community and voluntary organizations’ role in society where they gradually replace the state—in many cases with their encouragement and willing participation. As third sector organizations deliver public services, private investors are rewarded on a payment per output basis. Three case studies show how financialization through external shareholder interests is becoming a force in public service delivery.

Bile acid-based dual-functional prodrug nanoparticles for bone regeneration through hydrogen peroxide scavenging and osteogenic differentiation of mesenchymal stem cells

A high level of reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) upregulates pro-inflammatory cytokines and inhibits the osteogenic differentiation of mesenchymal stem cells (MSCs), which are key factors in bone regeneration. Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, has antioxidant and anti-inflammatory activities and also plays beneficial roles in bone regeneration by stimulating the osteogenic differentiation of MSCs while suppressing their adipogenic differentiation. Despite its remarkable capacity for bone regeneration, multiple injections of UDCA induce adverse side effects such as mechanical stress and contamination in bone defects. To fully exploit the beneficial roles of UDCA, a concept polymeric prodrug was developed based on the hypothesis that removal of overproduced H2O2 will potentiate the osteogenic functions of UDCA. In this work, we report bone regenerative nanoparticles (NPs) formulated from a polymeric prodrug of UDCA (PUDCA) with UDCA incorporated in its backbone through H2O2-responsive peroxalate linkages. The PUDCA NPs displayed potent antioxidant and anti-inflammatory activities in MSCs and induced osteogenic rather than adipogenic differentiation of the MSCs. In rat models of bone defect, the PUDCA NPs exhibited significantly better bone regeneration capacity and anti-inflammatory effects than equivalent amounts of UDCA. We anticipate that PUDCA NPs have tremendous translational potential as bone regenerative agents.

Growth differentiation factor-6 attenuates inflammatory and pain-related factors and degenerated disc-induced pain behaviors in rat model.

Previous studies have indicated that growth differentiation factor 6 (GDF6) is a potential candidate for intervertebral disc (IVD) degeneration (IDD) treatment. Here, we investigated the effect of GDF6 on IDD by examining changes in disc structure and the expression of inflammatory and pain-related factors. A rat posterior disc puncture model of single segments and three consecutive segments was constructed, and GDF6 or phosphate-buffered solution was administered via intradiscal injection 1 or 2 weeks after surgery. Magnetic resonance imaging showed a clear degeneration signal in the punctured disc, which was inhibited by GDF6. Histological staining revealed that GDF6 did not significantly improve the structure of IVDs in rats 8 weeks after puncture surgery, but it had an inhibitory effect on expression of the tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-1β in the IVD. Furthermore, GDF6 was found to protect the morphology and structure of the IVD 32 weeks after surgery. Mechanical and thermal hyperalgesia tests suggested that GDF6 injection can significantly improve mechanical and thermal-stimulated pain behavior in rats and inhibit the expression of inflammatory factors TNF-α and IL-1β and the pain factor calcitonin gene-related peptide in the dorsal root ganglion. A rat protein array test indicated that GDF6 could reduce the expression of cytokines IL-6, intercellular cell adhesion molecule-1, matrix metalloproteinase-13, IL-1β, and TNF-α and increase the expression of tissue inhibitor of metalloproteinases 1, Transforming growth factor-beta 2, IL-10, and resistin in a TNF-α-induced IDD cell model. Thus, our study demonstrates that GDF6 can improve the structure of the IVD, inhibit the expression of inflammatory and pain-related factors, and improve pain behavior in rats. Clinical Significance: To establish further preclinical research and clinical trials, comprehensive data are needed to validate the regenerative properties of GDF6. Ideally, a regenerative agent should also be able to relieve discogenic pain, achieving the best clinical outcomes.

ASPECTS OF CHOICE OF EMULSINATORS FOR COSMETIC PRODUCTS IN THE FORM OF SPRAY FOAM

Modern trends in the technology of cosmetics is the development of cosmetic compositions taking into account the basic requirements for these products (hypoallergenicity, naturalness of the base, the absence of artificial colors, a certain pH value, the effectiveness of photoprotective action, special requirements for polymer containers and packaging, etc.). In this case, first of all, attention should be paid to the main ingredients of almost every cosmetic product for the skin – amphiphilic compounds (surfactants), which should not irritate or damage the skin and skin. Cleansing and regenerative agents should include safe surfactants. In order to reduce the irritating effect on the skin, many products contain mixtures of several surfactants of the anionic type. For use in restorative cosmetics, it is proposed to consider a number of surfactants and their compositions, as well as to determine the most optimal combination of selected emulsifiers in the composition of a cosmetic product.Based on the results of the analytical review of the scientific literature and studies, conclusions are drawn about the possibility of using the composition of emulsifiers as a component of a cosmetic product in the form of spray foam. On the basis of the studies carried out on the colloidal-chemical properties of foaming systems for cosmetic purposes, the concentration limits for the introduction of emulsifying components in the formulation of the "GYDERLIFE-INTENSIVE" cosmetic product have been determined. According to the results of the study of the height of the column of foam and its stability in the cosmetic product "GYDERLIFE-INTENSIVE", the optimal ratio of emulsifiers in the formulation was established, which ensures high quality indicators of the cosmetic product, namely: Lanette SX – 1.85, PEG-7 Glyceryl Cocoate – 1, 08 Eumulgin B2 – 2.00 and sodium laureth sulfate –– 0.24 (mass fraction). The possibility of determining the height of the foam column and its activity in the studied cosmetic product according to current methods and their use as the MCC cosmetic product "GYDERLIFE-INTENSIVE" is shown.

Management of corneal neurotrophic ulcers with Cacicol®-RGTA (ReGeneraTing Agent): a case series

Abstract Purpose Neurotrophic corneal ulcers are difficult to treat and the conventional treatment often results in failure. A new matrix regenerative agent (“ReGeneraTing Agents”, RGTA), Cacicol® (Laboratoires Thea), has demonstrated good results over the last years. Therefore, the aim of this study was to evaluate the response to Cacicol® in a series of cases with corneal ulcers neurotrophic. Methods Retrospective case series. 11 patients with corneal ulcers unresponsive to conventional therapy underwent treatment with Cacicol®. One cycle included 1 drop every two days for 5 days. Results The range of conventional therapy prior to Cacicol® was 0–91 days. Upon introducing Cacicol® 82% (9/11) of the cases were cured and 18% (2/11) failed requiring an amniotic membrane transplant or penetrating keratoplasty. 67% (6/9) of the patients who had experienced healing required only one cycle of Cacicol®. 45% (5/11) patients needed more than one cycle of Cacicol®. One corneal bacterial ulcer responded favorably and one case related to Acanthamoeba failed. Most of the patients improved or maintained their visual acuity. Conclusion Cacicol® was a useful therapy in a high number of difficult neurotrophic corneal ulcers, including corneal infections. Some cases may require more than one cycle of Cacicol® or its immediate use to achieve the desired result.

Evaluation of efficiency and capacity of thermal, chemical and ultrasonic regeneration of tetracycline exhausted activated carbon

ABSTRACT Emerging pollutants have received increasing attention because of their potential environmental risks. As conventional treatment processes are not able to completely remove emerging pollutants, such as drugs, for example, the adsorption process is considered a complementary treatment. However, after some time of use, the adsorbent solids used in this type of process become saturated and there may be a higher demand for replacement of these materials, resulting in a large amount of solid waste. In this context, the objective of this study was to evaluate regeneration techniques of adsorbent solid depleted with emerging tetracycline pollutant. For this, tests were performed using three regenerative methods – thermal, chemical and ultrasonic, where through them were analyzed the influence of temperature, type of solvent and sonification time, respectively. Virgin, saturated and regenerated solids were characterized by their physical structure, micro and mesopore distribution and scanning electron microscopy. For all techniques employed, the regeneration efficiency reached values ⁣⁣above 85%. Thermal treatments at 200°C, 100% methanol solution, 100% deionized water with 60 °C heating and ultrasonic treatment at 5 and 20 minutes were chosen as the most viable methods for the study of adsorption/desorption cycles. Compared to the others, the heat treatment at 200°C remained with consistent results until the sixth cycle, presenting a regenerative capacity of 90%. Therefore, it has been selected as the most suitable regenerative agent, ensuring that CAG can be regenerated and used repeatedly in the treatment of tetracycline contaminated waters.

Split regeneration of chelating resins for the selective recovery of nickel and copper

The management of spent acids containing heavy metals has been traditionally carried out by neutralization-precipitation technologies that often fail to provide the required selectivity for metal recovery. This work proposed a split elution process using H2SO4 and NH4OH solutions to regenerate bispicolylamine-based chelating resins (Puromet™ MTS9600) employed in a previous work to separate nickel and copper from spent sulfuric acid effluents. Operation variables namely S/L ratio, concentration of the regeneration agents and process configuration were analysed to select the best conditions to optimize the metal unloading and their selective recovery in independent solutions. It was found that 43% of nickel was eluted from the resin by H2SO4 2.0 M and recovered with purities of 98% while 47% of copper was desorbed with NH4OH 2.0 M and recovered with purities of 97%. The long-term assessment evidenced that copper removal and metal recovery were not affected after 10 adsorption-regeneration cycles, while the nickel adsorption efficacy decreased about 10%.

Doped Zinc Oxide Nanoparticles: Synthesis, Characterization and Potential Use in Nanomedicine.

Smart nanoparticles for medical applications have gathered considerable attention due to an improved biocompatibility and multifunctional properties useful in several applications, including advanced drug delivery systems, nanotheranostics and in vivo imaging. Among nanomaterials, zinc oxide nanoparticles (ZnO NPs) were deeply investigated due to their peculiar physical and chemical properties. The large surface to volume ratio, coupled with a reduced size, antimicrobial activity, photocatalytic and semiconducting properties, allowed the use of ZnO NPs as anticancer drugs in new generation physical therapies, nanoantibiotics and osteoinductive agents for bone tissue regeneration. However, ZnO NPs also show a limited stability in biological environments and unpredictable cytotoxic effects thereof. To overcome the abovementioned limitations and further extend the use of ZnO NPs in nanomedicine, doping seems to represent a promising solution. This review covers the main achievements in the use of doped ZnO NPs for nanomedicine applications. Sol-gel, as well as hydrothermal and combustion methods are largely employed to prepare ZnO NPs doped with rare earth and transition metal elements. For both dopant typologies, biomedical applications were demonstrated, such as enhanced antimicrobial activities and contrast imaging properties, along with an improved biocompatibility and stability of the colloidal ZnO NPs in biological media. The obtained results confirm that the doping of ZnO NPs represents a valuable tool to improve the corresponding biomedical properties with respect to the undoped counterpart, and also suggest that a new application of ZnO NPs in nanomedicine can be envisioned.

Implantation of human adipose-derived stromal cells for the functional recovery of a murine heat-damaged muscle model.

In cases of lower rectum-located tumor or severe disease, surgical resection is currently the effective management; however, it also carries increased risks of function loss. The interdisciplinary field of regenerative medicine offers strategies that can potentially restore severely diseased and injured tissues and organs. Adipose-derived stromal cells (ASCs) are an abundant and accessible source of adult stem cells and hold great promise as therapeutic agents for tissue regeneration. In this work, we transplanted cells isolated from human stromal tissues, including a 6%-7% ASC population, into heat-damaged femoral muscles of non-obese diabetic immunodeficient mice. The movement of the limbs was observed to determine the functional recovery 3months after transplantation. Among the mice that did not receive cell transplantation, 20% were able to walk with the injured limb touching the ground, while all of the mice in the ASC-treatment group were able to walk. Furthermore, all ASC-treated mice were able to stand on both back paws, in contrast to the control group mice. The human stromal cell population containing ASCs was able to differentiate and engraft the injured muscle tissues successfully. Our results indicate that stromal material/ASC-based therapies are a promising strategy for the regeneration of tissues and function restoration after severe injury due to surgery.