Targeted genome editing restores auditory function in adult mice with progressive hearing loss caused by a human microRNA mutation.

Mutations in microRNA-96 ( MIR96 ) cause dominant delayed onset hearing loss DFNA50 without treatment. Genome editing has shown efficacy in hearing recovery by intervention in neonatal mice, yet editing in the adult inner ear is necessary for clinical applications. Here, we developed an editing therapy for a C>A point mutation in the seed region of the Mir96 gene, Mir96 14C>A associated with hearing loss by screening gRNAs for genome editors and optimizing Cas9 and sgRNA scaffold for efficient and specific mutation editing in vitro. By AAV delivery in pre-symptomatic (3-week-old) and symptomatic (6-week-old) adult Mir96 14C>A mutant mice, hair cell on-target editing significantly improved hearing long-term, with an efficacy inversely correlated with injection age. We achieved transient Cas9 expression without the evidence of AAV genomic integration to significantly reduce the safety concerns associated with editing. We developed an AAV-sgmiR96-master system capable of targeting all known human MIR96 mutations. As mouse and human MIR96 sequences share 100% homology, our approach and sgRNA selection for efficient and specific hair cell editing for long-term hearing recovery lays the foundation for future treatment of DFNA50 caused by MIR96 mutations.

Treatment of monogenic and digenic dominant genetic hearing loss by CRISPR-Cas9 ribonucleoprotein delivery in vivo.

Mutations in Atp2b2, an outer hair cell gene, cause dominant hearing loss in humans. Using a mouse model Atp2b2Obl/+, with a dominant hearing loss mutation (Oblivion), we show that liposome-mediated in vivo delivery of CRISPR-Cas9 ribonucleoprotein complexes leads to specific editing of the Obl allele. Large deletions encompassing the Obl locus and indels were identified as the result of editing. In vivo genome editing promotes outer hair cell survival and restores their function, leading to hearing recovery. We further show that in a double-dominant mutant mouse model, in which the Tmc1 Beethoven mutation and the Atp2b2 Oblivion mutation cause digenic genetic hearing loss, Cas9/sgRNA delivery targeting both mutations leads to partial hearing recovery. These findings suggest that liposome-RNP delivery can be used as a strategy to recover hearing with dominant mutations in OHC genes and with digenic mutations in the auditory hair cells, potentially expanding therapeutics of gene editing to treat hearing loss.

Reprogramming by drug-like molecules leads to regeneration of cochlear hair cell-like cells in adult mice.

Strategies to overcome irreversible cochlear hair cell (HC) damage and loss in mammals are of vital importance to hearing recovery in patients with permanent hearing loss. In mature mammalian cochlea, co-activation of Myc and Notch1 reprograms supporting cells (SC) and promotes HC regeneration. Understanding of the underlying mechanisms may aid the development of a clinically relevant approach to achieve HC regeneration in the nontransgenic mature cochlea. By single-cell RNAseq, we show that MYC/NICD "rejuvenates" the adult mouse cochlea by activating multiple pathways including Wnt and cyclase activator of cyclic AMP (cAMP), whose blockade suppresses HC-like cell regeneration despite Myc/Notch activation. We screened and identified a combination (the cocktail) of drug-like molecules composing of small molecules and small interfering RNAs to activate the pathways of Myc, Notch1, Wnt and cAMP. We show that the cocktail effectively replaces Myc and Notch1 transgenes and reprograms fully mature wild-type (WT) SCs for HC-like cells regeneration in vitro. Finally, we demonstrate the cocktail is capable of reprogramming adult cochlea for HC-like cells regeneration in WT mice with HC loss in vivo. Our study identifies a strategy by a clinically relevant approach to reprogram mature inner ear for HC-like cells regeneration, laying the foundation for hearing restoration by HC regeneration.

Microsphere embedded hydrogel construct - binary delivery of alendronate and BMP-2 for superior bone regeneration.

Biomimetic delivery of osteoinductive growth factors via an osteoconductive matrix is an interesting approach for stimulating bone regeneration. In this context, the bone extracellular matrix (ECM) has been explored as an optimal delivery system, since it releases growth factors in a spatiotemporal manner from the matrix. However, a bone ECM hydrogel alone is weak, unstable, and prone to microbial contamination and also has been reported to have significantly reduced bone morphogenic protein-2 (BMP-2) post decellularization. In the present work, a microsphere embedded osteoinductive decellularized bone ECM/oleoyl chitosan based hydrogel construct (BOC) was developed as a matrix allowing dual delivery of an anti-resorptive drug (alendronate, ALN, via the microspheres) and BMP-2 (via the hydrogel) for a focal tibial defect in a rabbit model. The synthesized gelatin microspheres (GMs) were spherical in shape with diameter ∼32 µm as assessed by SEM analysis. The BOC construct showed sustained release of ALN and BMP-2 under the studied conditions. Interestingly, amniotic membrane-derived stem cells (HAMSCs) cultivated on the hydrogel construct demonstrated excellent biocompatibility, cell viability, and active proliferation potential. Additionally, cell differentiation on the constructs showed an elevated expression of osteogenic genes in an RT-PCR study along with enhanced mineralized matrix deposition as demonstrated by alkaline phosphatase (ALP) assay and alizarin red assay. The hydrogel construct was witnessed to have improved neo-vascularization potential in a chick chorioalantoic membrane (CAM) assay. Also, histological and computed tomographic findings evidenced enhanced bone regeneration in the group treated with the BOC/ALN/BMP hydrogel construct in a rabbit tibial defect model. To conclude, the developed multifunctional hydrogel construct acts as an osteoinductive and osteoconductive platform facilitating controlled delivery of ALN and BMP-2, essential for stimulating bone tissue regeneration.

Decellularized bone matrix/oleoyl chitosan derived supramolecular injectable hydrogel promotes efficient bone integration.

Hydrogels derived from decellularized extracellular matrix (ECM) have been widely used as a bioactive matrix for facilitating functional bone tissue regeneration. However, its poor mechanical strength and fast degradation restricts the extensive use for clinical application. Herein, we present a crosslinked decellularized bone ECM (DBM) and fatty acid modified chitosan (oleoyl chitosan, OC) based biohybrid hydrogel (DBM/OC) for delivering human amnion-derived stem cells (HAMSCs) for bone regeneration. DBM/OC hydrogel were benchmarked against collagen-I/OC (Col-I/OC) based hydrogel in terms of their morphological characteristics, rheological analysis, and biological performances. DBM/OC hydrogel with its endogenous growth factors recapitulates the nanofibrillar 3D tissue microenvironment with improved mechanical strength and also exhibited antimicrobial potential along with superior proliferation/differentiation ability. HAMSCs encapsulation potential of DBM/OC hydrogel was established by well spread cytoskeleton morphology post 14 days of cultivation. Further, ex-vivo chick chorioallantoic membrane (CAM) assay revealed excellent neovascularization potential of DBM/OC hydrogel. Subcutaneously implanted DBM/OC hydrogel did not trigger any severe immune response or infection in the host after 21 days. Also, DBM/OC hydrogels and HAMSCs encapsulated DBM/OC hydrogels were implanted at the tibial defect in a rabbit model to assess the bone regeneration ability. Quantitative micro-CT and histomorphological analysis demonstrated that HAMSCs encapsulated DBM/OC hydrogel can support more mature mineralized bone formation at the defect area compared to DBM/OC hydrogel or SHAM. These findings manifested the efficacy of DBM/OC hydrogel as a functional cell-delivery vehicle and osteoinductive template to accelerate bone regeneration.

Dual Functionalized Injectable Hybrid Extracellular Matrix Hydrogel for Burn Wounds.

Low strength and rapid biodegradability of acellular dermal matrix (ADM) restrict its wider clinical application as a rapid cell delivery platform in situ for management of burn wounds. Herein, the extracted ADM was modified by a dual cross-linking approach with ionic crosslinking using chitosan and covalent cross-linking using an iodine-modified 2,5-dihydro-2,5-dimethoxy-furan cross-linker, termed as CsADM-Cl. In addition, inherent growth factors and cytokines were found to be preserved in CsADM-Cl, irrespective of ionic/covalent crosslinking. CsADM-Cl demonstrated improvement in post crosslinking stiffness with a decreased biodegradation rate. This hybrid crosslinked hydrogel supported adhesion, proliferation, and migration of human foreskin-derived fibroblasts and keratinocytes. Also, the angiogenic potential of CsADM-Cl was manifested by chick chorioallantoic membrane assay. CsADM-Cl showed excellent antibacterial activity against Escherichia coli and Staphylococcus aureus. Moreover, CsADM-Cl treated full thickness burn wounds and demonstrated rapid healing marked with superior angiogenesis, well-defined dermal-epidermal junctions, mature basket weave collagen deposition, and development of more pronounced secondary appendages. Altogether, the bioactive CsADM-Cl hydrogel established significant clinical potential to support wound healing as an apt injectable antibacterial matrix to encounter unmet challenges concerning critical burn wounds.

Carbon nanodot decorated acellular dermal matrix hydrogel augments chronic wound closure.

Impaired skin regeneration in chronic wounds like in diabetes corresponds to high oxidative stress, poor angiogenesis and insufficient collagen hyperplasia. Therefore, a multifaceted strategy for treatment is required to address critical issues associated with chronic wound healing. Fascinating application of nanomaterials in chronic wounds is still limited; hence, in the present work bioactive solubilized decellularized dermal matrix (sADM) was employed to form a hydrogel with chitosan (CTS) at physiological pH/temperature and modified with reactive oxygen species (ROS) scavenging carbon nanodots (ND). A detailed in vitro investigation found that the ND modified bioactive hydrogel (CsADMND) is suitable for human amniotic membrane derived stem cell (hAMSC) delivery. Also, CsADMND was observed to possess a good ROS scavenging property, hemocompatibility and pro-angiogenic potential as demonstrated by 2,2-diphenyl-1-picrylhydrazyl (DPPH), haemolysis and chick chorioallantoic membrane (CAM) assay, respectively. The hybrid hydrogel promoted migration of cells in vitro in scratch assay owing to its antioxidant potential and the presence of bioactive moieties. Further, its efficacy in healing full thickness (FT) chronic wounds was evaluated in a streptozotocin (STZ) induced diabetic model. The CsADMND hydrogel after association with hAMSCs led to stimulation of early angiogenesis, superior collagen deposition, rapid wound closure, complete reepithelialisation, and formation of distinct organized dermal epidermal junctions (DEJ) post 21 days of healing. These results suggest that the hAMSC laden CsADMND hydrogel may serve as a promising therapeutic strategy for the management of chronic wounds.

Bioinspired 3D porous human placental derived extracellular matrix/silk fibroin sponges for accelerated bone regeneration.

Critical bone defects arising from traumatic injury and diseases are of major health concern since they are unable to heal spontaneously without clinical intervention. In this context, bone tissue engineering provides an attractive approach to treat bone defects by providing a bioactive template which has the potential to guide osseous tissue regeneration. In this study, porous hybrid placental extracellular matrix sponge (PIMS) was fabricated by a combinatorial method using silk fibroin (SF)/placental derived extracellular matrix and subsequently evaluated its efficacy towards bone tissue regeneration. The presence of intrinsic growth factors was evidenced by immunoblotting of the extracted proteins derived from the placental derived extracellular matrix. This growth factor rich PIMS lends a unique bioactive scaffolding to human amniotic mesenchymal stem cells (HAMSCs) which supported enhanced proliferation as well as superior osteogenic differentiation. Gene expression studies demonstrated significant up-regulation of osteogenic related genes in the PIMS group. PIMS when implanted in the chick chorioallantoic membrane, significantly attracted allantoic vessels revealing its potential to stimulate angiogenesis ex vivo. Furthermore, no severe immune response to the host was observed on subcutaneous implantation of PIMS in vivo. Instead, it supported the formation of blood vessels, revealing its outstanding biocompatibility. Additionally, critical tibial defects treated with PIMS demonstrated higher bone volume after six weeks when analyzed by micro-CT, which was accompanied by high mineral density. Histological and immunofluorescence studies validated the results and revealed enhanced osseous tissue regeneration after six weeks of surgery. All these findings recapitulated that the growth factors incorporated bioactive PIMS could perform as an appropriate matrix for osteogenic differentiation and efficient bone regeneration.

Novel pH-sensitive alginate hydrogel delivery system reinforced with gum tragacanth for intestinal targeting of nutraceuticals.

The present study utilizes the novel combination of Gum tragacanth (GT) and sodium alginate (SA) to reinforce SA hydrogel beads. The composite hydrogel beads were encapsulated with phenolic compounds extracted from Basella sps. The rheological studies conferred increased elastic property of GT incorporated formulations. Higher swelling behavior was observed in simulated intestinal fluid (SIF) with increasing GT content in SA formulations. SA-GT composite hydrogels revealed increased encapsulation efficiency with sustained release of phenolic compounds in SIF. GT incorporated hydrogel beads exhibited increased biodegradation (up to 82% weight loss) in biodegradation media (in vitro). FTIR study found no molecular interaction between SA and GT. TGA analysis revealed that GT incorporation did not affect the thermal behavior of SA. Furthermore, SA-GT encapsulated hydrogels showed remarkable cytotoxicity against osteosarcoma cells. Thus our findings suggest SA-GT gel formulation could be used as a promising delivery system for drugs and nutraceutical compounds.

Impact of styrene maleic anhydride (SMA) based hydrogel on rat fallopian tube as contraceptive implant with selective antimicrobial property.

Development of non-hormonal female contraception is a need to combat against increasing population growth. The presently available short term or long term female contraceptives and sterilization methods have their own restrictions and side effects. With this objective, herein, we describe an innovative insight about the use of hydrogel formulation consisting of Styrene Maleic Anhydride (SMA) dissolved in Dimethyl Sulfoxide (DMSO) as non-hormonal fallopian tube contraceptive implant. Firstly, in vitro behavior of SMA hydrogel was evaluated by in vitro swelling and rheological properties to comprehend the polymeric hydrogel property post implantation inside the fallopian tube. Simulated Uterine Fluid (SUF) was used to simulate female reproductive tract environment in this study. Mechanical strength of the hydrogel when subjected to dynamic environment post implantation in the fallopian tube was estimated by the G' values demonstrated. SMA hydrogel expressed selective antimicrobial activity against opportunistic pathogens (Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus) while having limited consequence over the growth of Lactobacillus spp. After confirmation of cytocompatibility against primary rat endometrial cell lines, the polymeric hydrogel was implanted inside the uterine horns of Sprague-Dawley rats. In vivo biocompatibility of the hydrogel was confirmed by histological and immunohistochemical evaluation of uterine tissue sections. Hematology, blood biochemistry and organ toxicity (kidney, liver, spleen, lungs and heart) also revealed biocompatibility of SMA hydrogel. The results of the current study indicated that the SMA copolymer dissolved in DMSO to form hydrogel has excellent biocompatibility for application as female contraceptive gel which can be implanted in the fallopian tube.

Osteochondral Defects Healing Using Extracellular Matrix Mimetic Phosphate/Sulfate Decorated GAGs-Agarose Gel and Quantitative Micro-CT Evaluation.

Tissue engineering has a major emphasis in creating tissue specific extracellular ambiance by altering chemical functionalities of scaffold materials. Heterogeneity of osteochondral tissue necessitates tailorable bone and cartilage specific extracellular environment. Carboxylate- and sulfate-functionalized glycosaminoglycans (GAGs) in cartilage extracellular matrix (ECM) create an acidic ambience to support chondrogenic activity, whereas phosphate-rich environment in bone enables chelation of calcium leading to the formation of mineralized matrix along with an alkaline environment to support osteogenesis. In this study, chitosan, a naturally occurring GAGs, was functionalized with phosphate/sulfate groups analogous to bone/cartilage ECM and incorporated in thermogelling agarose hydrogel for delivery to osteochondral defects. In vitro studies revealed significantly higher adhesion and proliferation of adipose derived mesenchymal stem cells (ADMSCs) with blended hydrogels as compared to that of native agarose. Cell differentiation and RT-PCR studies of the phosphorylated hydrogels revealed higher osteogenic potential, while sulfated hydrogels demonstrated enhanced chondrogenic activity in comparison to agarose. Recovery of osteochondral defects after delivery of the thermoresponsive agarose-based hydrogels decorated with phosphorylated derivatives showed significantly higher bone formation. On the other hand, cartilage formation was significant with chitosan sulfate decorated hydrogels. The study highlights the role of chitosan derivatives in osteochondral defect healing, especially phosphorylated ones as bone promoter, whereas sulfated ones act as cartilage enhancer, which was quantitatively distinguished through micro-CT-based noninvasive imaging and analysis.

Core-Shell Nanofibrous Scaffold Based on Polycaprolactone-Silk Fibroin Emulsion Electrospinning for Tissue Engineering Applications.

The vast domain of regenerative medicine comprises complex interactions between specific cells' extracellular matrix (ECM) towards intracellular matrix formation, its secretion, and modulation of tissue as a whole. In this domain, engineering scaffold utilizing biomaterials along with cells towards formation of living tissues is of immense importance especially for bridging the existing gap of late; nanostructures are offering promising capability of mechano-biological response needed for tissue regeneration. Materials are selected for scaffold fabrication by considering both the mechanical integrity and bioactivity cues they offer. Herein, polycaprolactone (PCL) (biodegradable polyester) and 'nature's wonder' biopolymer silk fibroin (SF) are explored in judicious combinations of emulsion electrospinning rather than conventional electrospinning of polymer blends. The water in oil (W/O) emulsions' stability is found to be dependent upon the concentration of SF (aqueous phase) dispersed in the PCL solution (organic continuous phase). The spinnability of the emulsions is more dependent upon the viscosity of the solution, dominated by the molecular weight of PCL and its concentration than the conductivity. The nanofibers exhibited distinct core-shell structure with better cytocompatibility and cellular growth with the incorporation of the silk fibroin biopolymer.

Silk Sponges Ornamented with a Placenta-Derived Extracellular Matrix Augment Full-Thickness Cutaneous Wound Healing by Stimulating Neovascularization and Cellular Migration.

Regeneration of full-thickness wounds without scar formation is a multifaceted process, which depends on in situ dynamic interactions between the tissue-engineered skin substitutes and a newly formed reparative tissue. However, the majority of the tissue-engineered skin substitutes used so far in full-thickness wound healing cannot mimic the natural extracellular matrix (ECM) complexity and thus are incapable of providing a suitable niche for endogenous tissue repair. Herein, we demonstrated a simple approach to fabricate porous hybrid ECM sponges (HEMS) using a placental ECM and silk fibroin for full-thickness wound healing. HEMS with retained cytokines/growth factors provided a noncytotoxic environment in vitro for human foreskin fibroblasts (HFFs), human epidermal keratinocytes (HEKs), and human amniotic membrane-derived stem cells to adhere, infiltrate, and proliferate. Interestingly, HEMS-conditioned media accelerated the migration of HFFs and HEKs owing to the presence of cytokines/growth factors. Also, the ex vivo chick chorioallantoic membrane assay of HEMS demonstrated its excellent vascularization potential by inducing and supporting blood vessels. Additionally, HEMS when subcutaneously implanted demonstrated no severe immune response to the host. Furthermore, HEMS implanted in full-thickness wounds in a rat model showed augmented healing progression with well-organized epidermal-dermal junctions via pronounced angiogenesis, accelerated migration of HFFs/HEKs, enhanced granulation tissue formation, and early re-epithelialization. Taken together, these findings show that porous HEMS ornamented with cytokines/growth factors having superior physicomechanical properties may be an appropriate skin substitute for full-thickness cutaneous wounds.

Identification and characterization of bioactive phenolic constituents, anti-proliferative, and anti-angiogenic activity of stem extracts of Basella alba and rubra.

Basella is an important green leafy vegetable species of Chenopodiaceae family and is known for its medicinal properties. Hydroxy-benzoic acids, hydroxy-cinnamic acids and flavones groups were identified and characterized from the aqueous stem extracts of B. alba and B. rubra species. Higher values of phenolics as well as antioxidant activity were noted from B. alba species extracts. The evaluation of the cytoxicity of these extracts on A431 (epidermoid carcinoma), Hep G2 (hepatocellular carcinoma) and MG 63 (osteosarcoma) cells indicated anti-proliferative activity against all the cell lines. B. alba extract showed higher anti-proliferative activity (37.95-84.86%). Chick embryo chorioallantoic membrane (CAM) assay revealed inhibition of neo-vessels formation. Significant suppression was found with extracts of B. alba at 7 mg/ml compared to that of B. rubra. This is the first study to report the anti-angiogenic activity of Basella species. These studies indicate that Basella sps can be used as a source of natural antioxidants and can be of high significance in pharmaceutical and nutraceutical industries.

Simultaneous hydrothermal bioactivation with nano-topographic modulation of porous titanium alloys towards enhanced osteogenic and antimicrobial responses.

Post-implantation failure associated with insufficient host tissue integration at the bone-implant interface and aseptic loosening is a major concern in orthopaedics as well as in dentistry. To overcome the failure in early stages of implantation, prosthetic design combining the mechanisms of porosity guided bone ingrowth along with topographic manipulation of osteogenic cells over bacterial colonization would be an ideal choice, although achieving such a goal is highly challenging. In this study, facile rapid hydrothermal synthesis of nanostructures with simultaneous deposition of hydroxyapatite on the titanium alloy surface was demonstrated by using an aqueous sodium tripolyphosphate and calcium hydroxide mixture. Nanostructures with wire-like morphology exhibited significantly higher osteogenic related gene expression (COL I, OPN, and OCN) through differentiation of adipose derived mesenchymal stem cells as well as the bactericidal response against S. aureus and E. coli as compared to other nanotopographic features. The same also exhibited elongated cell morphology with the highest expression of paxillin towards cell boundaries as compared to the polished surface with flattened cell morphology and localized expression of paxillin around the nucleus. Implantation of treated porous Ti6Al4V samples representing a multiscalar hierarchy with wire-like nanostructures accelerated osteochondral healing in rabbits without any major signs of infection. Also, significantly higher bone formation was observed within the defects implanted with treated porous Ti6Al4V (44.0%) as compared to that of untreated porous samples (36.9%) as well as empty defects (19.6%).

Polycaprolactone nanofibers functionalized with placental derived extracellular matrix for stimulating wound healing activity.

Impaired wound healing is primarily associated with inadequate angiogenesis, repressed cell migration, deficient synthesis of extracellular matrix (ECM) component/growth factors, and altered inflammatory responses in the wound bed environment. Herein, we report a simple process for the fabrication of PCL nanofiber mats embedded with placental-derived bioactive molecules (PCL-sPEM) rich in growth factors for full-thickness cutaneous wound healing. The physicochemical attributes and biological composition of PCL-sPEM nanofiber mats delivered a nontoxic environment in vitro and significantly promoted the adhesion, infiltration, and proliferation of human fibroblasts/keratinocytes. Conditioned media extracted from PCL-sPEM nanofiber mats enhanced the migration potential of the cells (fibroblasts/keratinocytes) involved in wound healing due to the release of growth factors embedded in it. Further, PCL-sPEM nanofiber mats attracted, stimulated and supported vascularization as determined by the Chick Chorioallantoic Membrane (CAM) assay. Interestingly, critical skin wounds of rats treated with PCL-sPEM nanofiber mats facilitated improved wound closure with well-organized dermis and epidermis, which could be ascribed to prominent vascularization, augmented migration of human foreskin fibroblasts (HFFs) & human epidermal keratinocytes (HEKs), increased collagen synthesis and early re-epithelialization. Collectively, our results suggest that PCL-sPEM nanofiber mats embedded with growth factors could be a suitable matrix for treating critical full-thickness wounds.

Influence of Porosity and Pore-Size Distribution in Ti6Al4 V Foam on Physicomechanical Properties, Osteogenesis, and Quantitative Validation of Bone Ingrowth by Micro-Computed Tomography.

Cementless fixation for orthopedic implants aims to obviate challenges associated with bone cement, providing long-term stability of bone prostheses after implantation. The application of porous titanium and its alloy-based implants is emerging for load-bearing applications due to their high specific strength, low stiffness, corrosion resistance, and superior osteoconductivity. In this study, coagulant-assisted foaming was utilized for the fabrication of porous Ti6Al4 V using egg-white foam. Samples with three different porosities of 68.3%, 75.4%, and 83.1% and average pore sizes of 92, 178, and 297 µm, respectively, were prepared and subsequently characterized for mechanical properties, osteogenesis, and tissue ingrowth. A microstructure-mechanical properties relationship study revealed that an increase of porosity from 68.3 to 83.1% increased the average pore size from 92 to 297 µm with the subsequent reduction of compresive strength by 85% and modulus by 90%. Samples with 75.4% porosity and a 178 µm average pore size produced signifcant osteogenic effects on human mesenchymal stem cells, which was further supported by immunocytochemistry and real-time polymerase chain reaction data. Quantitative assessment of bone ingrowth by micro-computed tomography revealed that there was an approximately 52% higher bone formation and more than 90% higher bone penetration at the center of femoral defects in rabbit when implanted with Ti6Al4 V foam (75.4% porosity) compared to the empty defects after 12 weeks. Hematoxylin and eosin (H&E) and Masson trichrome (MT) staining along with energy-dispersive X-ray mapping on the sections obtained from the retrieved bone samples support bone ingrowth into the implanted region.

In Situ Silver Nanowire Deposited Cross-Linked Carboxymethyl Cellulose: A Potential Transdermal Anticancer Drug Carrier.

Recently, a novel biopolymeric nanocomposite hydrogel comprised of in situ formed silver nanowires (AgNWs) deposited chemically cross-linked carboxymethyl cellulose (CMC) has been developed, which demonstrates superior efficacy as anticancer drug-curcumin carrier. The cross-linked polymer has been prepared by grafting poly [2-(methacryloyloxy) ethyl trimethylammonium chloride] on CMC using diethylene glycol dimethacrylate cross-linker. The nanocomposite hydrogel has the capability to encapsulate both hydrophobic/hydrophilic transdermal drugs. With variation in reaction conditions/parameters, several composite materials have been synthesized and depending on lower swelling/higher cross-linking and greater gel strength, an optimized grade of nanocomposite hydrogel has been selected. The developed nanocomposite hydrogel is characterized with FTIR/NMR spectra, FESEM/XRD/TGA/AFM/XPS analyses, and UV-visible spectroscopy. Rheological study has been performed to enlighten the gel strength of the composite material. The synthesized nanocomposite hydrogel is biodegradable and nontoxic to mesenchymal stem cells (hMSCs). In vitro release of curcumin suggests that in situ incorporation of AgNWs on cross-linked CMC enhanced the penetration power of nanocomposite hydrogel and released the drug in sustained way (∼62% for curcumin released in 4 days). Ex vivo rat skin permeation study confirms that the drug from both the cross-linked and nanocomposite hydrogel was permeable through the rat skin in controlled fashion. Additionally the curcumin loaded composite hydrogel can efficiently kill the MG 63 cancer cells, which has been confirmed by apoptosis study and therefore, probably be a suitable carrier for curcumin delivery toward cancer cells.

Accelerated healing of full thickness dermal wounds by macroporous waterborne polyurethane-chitosan hydrogel scaffolds.

Wound healing is a dynamic process wherein cells, and macromolecules work in consonance to facilitate tissue regeneration and restore tissue integrity. In the case of full-thickness (FT) wounds, healing requires additional support from native or synthetic matrices to aid tissue regeneration. In particular, a matrix with optimum hydrophilic-hydrophobic balance which will undergo adequate swelling as well as reduce bacterial adhesion has remained elusive. In the present study, polyurethane diol dispersion (PUD) and the anti-bacterial chitosan (Chn) were blended in different ratios which self-organized to form macroporous hydrogel scaffolds (MHS) at room temperature on drying. SEM and AFM micrographs revealed the macroporosity on top and fracture surfaces of the MHS. FTIR spectra revealed the intermolecular as well as intra-molecular hydrogen bonding interactions between the two polymers responsible for phase separation, which was also observed by micrographs of blend solutions during the drying process. The effect of phase separation on mechanical properties and in vitro degradation (hydrolytic, enzymatic and pH dependent) of MHS were studied and found to be suitable for wound healing. In vitro cytocompatibility was demonstrated by the proliferation of primary rat fibroblast cells on MHS. Selected MHS was subjected to in vivo FT wound healing study in Wistar rats and compared with an analogous polyurethane containing commercial dressing i.e. Tegaderm™. The MHS-treated wounds demonstrated accelerated healing with increased wound contraction, higher collagen synthesis, and vascularization in wound area compared to Tegaderm™. Thus, it is concluded that the developed MHS is a promising candidate for application as FT wound healing dressings.

Mycobacterial heat shock protein 65 mediated metabolic shift in decidualization of human endometrial stromal cells.

Successful implantation is dependent on the appropriate decidualization of endometrial stromal cells for the establishment of pregnancy in women. Mycobacterial heat shock protein 65 (HSP65) is involved in pathogenesis of the genital tuberculosis (GTB), one of the common causes of infertility in emerging countries. Though implantation failure appears to be the major cause, understanding the status of decidualizaiton process in women diagnosed with GTB has not been thoroughly addressed. We, therefore, explored the effect of HSP65 protein on the endometrial cell metabolism during in vitro decidualization. In order to identify the cellular metabolism of decidual cells with and without HSP65 treatment, proton NMR based characterization of metabolites extracted from cells and culture media were performed. In presence of HSP65, significant reduction in the decidual phenotype of endometrial stromal cells and prolactin expression is suggestive of impairment in decidualization. The intracellular and extracellular metabolic changes in HSP65 treated endometrial stromal cells produced a distinct pattern, reflecting the interaction between the protein and cellular metabolism. HSP65 mediated dysregulation in cellular metabolism is associated with poor decidualization. Besides enriching the present knowledge on metabolic changes underlying stromal cells decidualization, these findings assist in identifying potential molecular causes for decidualization failure in GTB women.