Effect of Tannic Acid Concentrations on Temperature-Sensitive Sol-Gel Transition and Stability of Tannic Acid/Pluronic F127 Composite Hydrogels.

Recently, interest in polyphenol-containing composite adhesives for various biomedical applications has been growing. Tannic acid (TA) is a polyphenolic compound with advantageous properties, including antioxidant and antimicrobial properties. Additionally, TA contains multiple hydroxyl groups that exhibit biological activity by forming hydrogen bonds with proteins and biomacromolecules. Furthermore, TA-containing polymer composites exhibit excellent tissue adhesion properties. In this study, the gelation behavior and adhesion forces of TA/Pluronic F127 (TA/PluF) composite hydrogels were investigated by varying the TA and PluF concentrations. PluF (above 16 wt%) alone showed temperature-responsive gelation behavior because of the closely packed micelle aggregates. After the addition of a small amount of TA, the TA/PluF hydrogels showed thermosensitive behavior similar to that of PluF hydrogels. However, the TA/PluF hydrogels containing more than 10 wt% TA completely suppressed the thermo-responsive gelation kinetics of PluF, which may have been due to the hydrogen bonds between TA and PluF. In addition, TA/PluF hydrogels with 40 wt% TA showed excellent tissue adhesion properties and bursting pressure in porcine intestinal tissues. These results are expected to aid in understanding the use of mixtures of TA and thermosensitive block copolymers to fabricate adhesive hydrogels for versatile biomedical applications.

Hydrophilic/Hydrophobic Janus Nanofibers Containing Compound K for Cartilage Regeneration.

Introduction: Cartilage regeneration is a challenging issue due to poor regenerative properties of tissues. Electrospun nanofibers hold enormous potentials for treatments of cartilage defects. However, nanofibrous materials used for the treatment of cartilage defects often require physical and/or chemical modifications to promote the adhesion, proliferation, and differentiation of cells. Thus, it is highly desirable to improve their surface properties with functionality. We aim to design hydrophilic, adhesive, and compound K-loaded nanofibers for treatments of cartilage defects. Methods: Hydrophilic and adhesive compound K-containing polycaprolactone nanofibers (CK/PCL NFs) were prepared by coatings of gallic acid-conjugated chitosan (CHI-GA). Therapeutic effects of CHI-GA/CK/PCL NFs were assessed by the expression level of genes involved in the cartilage matrix degradation, inflammatory response, and lipid accumulations in the chondrocytes. In addition, Cartilage damage was evaluated by safranin O staining and immunohistochemistry of interleukin-1ß (IL-1ß) using OA animal models. To explore the pathway associated with therapeutic effects of CHI-GA/CK/PCL NFs, cell adhesion, phalloidin staining, and the expression level of integrins and peroxisome proliferator-activated receptor (PPARs) were evaluated. Results: CHI-GA-coated side of the PCL NFs showed hydrophilic and adhesive properties, whereas the unmodified opposite side remained hydrophobic. The expression levels of genes involved in the degradation of the cartilage matrix, inflammation, and lipogenesis were decreased in CHI-GA/CK/PCL NFs owing to the release of CK. In vivo implantation of CHI-GA/CK/PCL NFs into the cartilage reduced cartilage degradation induced by destabilization of the medial meniscus (DMM) surgery. Furthermore, the accumulation of lipid deposition and expression levels of IL-1ß was reduced through the upregulation of PPAR. Conclusion: CHI-GA/CK/PCL NFs were effective in the treatments of cartilage defects by inhibiting the expression levels of genes involved in cartilage degradation, inflammation, and lipogenesis as well as reducing lipid accumulation and the expression level of IL-1ß via increasing PPAR.

Synergistic Combination of Dual Clays in Multilayered Nanocomposites for Enhanced Flame Retardant Properties.

In an effort to reduce the flammability of synthetic polymeric materials such as cotton fabrics and polyurethane foam (PUF), hybrid nanocoatings are prepared by layer-by-layer assembly. Multilayered nanocomposites of a cationic polyelectrolyte, poly(diallyldimethylammonium chloride) (PDDA), are paired with two kinds of clay nanoplatelets, montmorillonite (MMT) and vermiculite (VMT). The physical properties such as thickness and mass and thermal behaviors in clay-based nanocoatings with and without incorporation of tris buffer are compared to assess the effectiveness of amine salts on flame retardant (FR) performances. A PDDA-tris/VMT-MMT system, in which tris buffer is introduced into the cationic PDDA aqueous solution, produces a thicker and heavier coating. Three different systems, including PDDA/MMT, PDDA/VMT-MMT, and PDDA-tris/VMT-MMT, result in conformal coating, retaining the weave structure of the fabrics after being exposed to a vertical and horizontal flame test, while the uncoated sample is completely burned out. The synergistic effects of dual clay-based hybrid nanocoatings are greatly improved by adding amine salts. Cone calorimetry reveals that the PDDA-tris/VMT-MMT-coated PUF eliminates a second peak heat release rate and significantly reduces other FR performances, compared to those obtained from the clay-based multilayer films with no amine salts added. Ten bilayers of PDDA-tris/VMT-MMT (≈250 nm thick) maintain the shape of foam after exposure to a butane torch flame for 12 s. As for practical use of these nanocomposites in real fire disasters, spray-assisted PDDA-tris/VMT-MMT multilayers on woods exhibit high resistance over flammability. Improved fire resistance in PDDA-tris/VMT-MMT is believed to be due to the enhanced char yield through the addition of tris buffer that promotes the deposition of more clay particles while retaining a highly ordered deposition of a densely packed nanobrick wall structure. This work demonstrates the ability to impart significant fire resistance to synthetic polymer materials in a fully renewable nanocoating that uses environmentally benign chemistry.

Coagulant Protein-Free Blood Coagulation Using Catechol-Conjugated Adhesive Chitosan/Gelatin Double Layer.

Since the discovery of polyphenolic underwater adhesion in marine mussels, researchers strive to emulate this natural phenomenon in the development of adhesive hemostatic materials. In this study, bio-inspired hemostatic materials that lead to pseudo-active blood coagulation, utilizing traditionally passive polymer matrices of chitosan and gelatin are developed. The two-layer configuration, consisting of a thin, blood-clotting catechol-conjugated chitosan (CHI-C) layer and a thick, barrier-functioning gelatin (Geln) ad-layer, maximizes hemostatic capability and usability. The unique combination of coagulant protein-free condition with CHI-C showcases not only coagulopathy-independent blood clotting properties (efficacy) but also exceptional clinical potential, meeting all necessary biocompatibility evaluation (safety) without inclusion of conventional coagulation triggering proteins such as thrombin or fibrinogen. As a result, the CHI-C/Geln is approved by the Ministry of Food and Drug Safety (MFDS, Republic of Korea) as a class II medical device. Hemostatic efficacy observed in multiple animal models further demonstrates the superiority of CHI-C/Geln sponges in achieving quick hemostasis compared to standard treatments. This study not only enriches the growing body of research on mussel-inspired materials but also emphasizes the potential of biomimicry in developing advanced medical materials, contributing a promising avenue toward development of readily accessible and affordable hemostatic materials.

Upregulated FOXM1 stimulates chondrocyte senescence in Acot12-/-Nudt7-/- double knockout mice.

Rationale: One of the hallmarks of osteoarthritis (OA), the most common degenerative joint disease, is increased numbers of senescent chondrocytes. Targeting senescent chondrocytes or signaling mechanisms leading to senescence could be a promising new therapeutic approach for OA treatment. However, understanding the key targets and links between chondrocyte senescence and OA remains unclear. Methods: Senescent chondrocytes were identified from Nudt7-/-, Acot12-/-, double-knockout mice lacking Acot12 and Nudt7 (dKO) and applied to microarray. The presence of forkhead transcription factor M1 (FOXM1) was detected in aged, dKO, and destabilization of the medial meniscus (DMM) cartilages and articular chondrocytes, and the effect of FoxM1 overexpression and acetyl-CoA treatment on cartilage homeostasis was examined using immunohistochemistry, quantitative real-time PCR (qRT-PCR), cell apoptosis and proliferation assay, and safranin O staining. Delivery of Rho@PAA-MnO2 (MnO2 nanosheet) or heparin-ACBP/COS-GA-siFoxM1 (ACBP-siFoxM1) nanoparticles into DMM cartilage was performed. Results: Here, we propose the specific capture of acetyl-CoA with the delivery of (FoxM1 siRNA (siFoxM1) to prevent cartilage degradation by inhibiting the axis of chondrocyte senescence. dKO stimulate chondrocyte senescence via the upregulation of FoxM1 and contribute to severe cartilage breakdown. We found that the accumulation of acetyl-CoA in the dKO mice may be responsible for the upregulation of FoxM1 during OA pathogenesis. Moreover, scavenging reactive oxygen species (ROS) induced by chondrocyte senescence via the implantation of MnO2 nanosheets or delivery of siFoxM1 functionalized with acetyl-CoA binding protein (ACBP) to capture acetyl-CoA using an injectable bioactive nanoparticle (siFoxM1-ACBP-NP) significantly suppressed DMM-induced cartilage destruction. Conclusion: We found that the loss of Acot12 and Nudt7 stimulates chondrocyte senescence via the upregulation of FoxM1 and accumulation of acetyl-CoA, and the application of siFoxM1-ACBP-NP is a potential therapeutic strategy for OA treatment.

Intergranular Shielding for Ultrafine-Grained Mo-Doped Ni-Rich Li[Ni0.96 Co0.04 ]O2 Cathode for Li-Ion Batteries with High Energy Density and Long Life.

Deploying Ni-enriched (Ni≥95 %) layered cathodes for high energy-density lithium-ion batteries (LIBs) requires resolving a series of technical challenges. Among them, the structural weaknesses of the cathode, vigorous reactivity of the labile Ni4+ ion species, gas evolution and associated cell swelling, and thermal instability issues are critical obstacles that must be solved. Herein, we propose an intuitive strategy that can effectively ameliorate the degradation of an extremely high-Ni-layered cathode, the construction of ultrafine-scale microstructure and subsequent intergranular shielding of grains. The formation of ultrafine grains in the Ni-enriched Li[Ni0.96 Co0.04 ]O2 (NC96) cathode, achieved by impeding particle coarsening during cathode calcination, noticeably improved the mechanical durability and electrochemical performance of the cathode. However, the buildup of the strain-resistant microstructure in Mo-doped NC96 concurrently increased the cathode-electrolyte contact area at the secondary particle surface, which adversely accelerated parasitic reactions with the electrolyte. The intergranular protection of the refined microstructure resolved the remaining chemical instability of the Mo-doped NC96 cathode by forming an F-induced coating layer, effectively alleviating structural degradation and gas generation, thereby extending the battery's lifespan. The proposed strategies synergistically improved the structural and chemical durability of the NC96 cathode, satisfying the energy density, life cycle performance, and safety requirements for next-generation LIBs.

Bio-Inspired Self-Healing, Shear-Thinning, and Adhesive Gallic Acid-Conjugated Chitosan/Carbon Black Composite Hydrogels as Suture Support Materials.

The occurrence of leakage from anastomotic sites is a significant issue given its potential undesirable complications. The management of anastomotic leakage after gastrointestinal surgery is particularly crucial because it is directly associated with mortality and morbidity in patients. If adhesive materials could be used to support suturing in surgical procedures, many complications caused by leakage from the anastomosis sites could be prevented. In this study, we have developed self-healing, shear-thinning, tissue-adhesive, carbon-black-containing, gallic acid-conjugated chitosan (CB/Chi-gallol) hydrogels as sealing materials to be used with suturing. The addition of CB into Chi-gallol solution resulted in the formation of a crosslinked hydrogel with instantaneous solidification. In addition, these CB/Chi-gallol hydrogels showed enhancement of the elastic modulus (G') values with increased CB concentration. Furthermore, these hydrogels exhibited excellent self-healing, shear-thinning, and tissue-adhesive properties. Notably, the hydrogels successfully sealed the incision site with suturing, resulting in a significant increase in the bursting pressure. The proposed self-healing and adhesive hydrogels are potentially useful in versatile biomedical applications, particularly as suture support materials for surgical procedures.

Adhesive ginsenoside compound K patches for cartilage tissue regeneration.

Biomaterial-based drug delivery systems have been developed to expedite cartilage regeneration; however, challenges related to drug recovery, validation, and efficient drug delivery remain. For instance, compound K (CK) is a major metabolite of ginsenosides that is known to protect against joint degeneration by inhibiting the production of inflammatory cytokines and the activation of immune cells. However, its effects on cartilage degradation and tissue regeneration remain unclear. Additionally, tissue-adhesive drug delivery depots that stably adhere to cartilage defects are required for CK delivery. In this study, CK-loaded adhesive patches were reported to seal cartilage defects and deliver CK to defect sites, preventing cartilage degradation and accelerating cartilage tissue regeneration. Adhesive patches are stable and suitable for application in surgical procedures under physiological conditions and show excellent adhesiveness to cartilage surfaces. In addition, there were no significant differences in the adhesive polymeric networks before and after CK loading. CK-loaded hydrocaffeic acid-conjugated chitosan patches significantly inhibited the stimulation of cartilage-degrading enzymes and apoptosis in osteoarthritic cartilage by releasing CK in cartilage defects. Additionally, the NFkB signaling pathway of released CK from the adhesive patches in the treatment of osteoarthritis is revealed. Thus, the CK-loaded adhesive patches are expected to significantly contribute to cartilage regeneration.

Double-layer adhesives for preventing anastomotic leakage and reducing post-surgical adhesion.

Preventing anastomotic leakage (AL) and postoperative adhesions after gastrointestinal surgery is crucial for ensuring a favorable surgical prognosis. However, AL prevention using tissue adhesives can unintentionally lead to undesirable adhesion formation, while anti-adhesive agents may interfere with wound healing and contribute to AL. In this study, we have developed a double-layer patch, consisting of an adhesive layer on one side, utilizing gallic acid-conjugated chitosan (CHI-G), and an anti-adhesive layer on the opposite side, employing crosslinked hyaluronic acid (cHA). These CHI-G/cHA double-layer adhesives significantly prevented AL by forming physical barriers of CHI-G and reduced post-surgical adhesion at the anastomosis sites by the anti-adhesive layers of cHA. The bursting pressure (161.1 ± 21.6 mmHg) of double-layer adhesives-applied rat intestine at postoperative day 21 was far higher than those of the control (129.4 ± 5.7 mmHg) and the commercial anti-adhesives-applied group (120.8 ± 5.2 mmHg). In addition, adhesion score of double-layer adhesives-applied rat intestine was 3.6 ± 0.3 at postoperative day 21, which was similar to that of the commercial anti-adhesives-applied group (3.6 ± 0.3) and lower than that of the control group (4.9 ± 0.5). These findings indicate that the double-layer patch (CHI-G/cHA) has the potential to effectively prevent both postoperative adhesions and anastomotic leakage, offering a promising solution for gastrointestinal surgery.

Effect of polydopamine and fluoride ion coating on dental enamel remineralization: an in vitro study.

BACKGROUND: Fluoride treatment is one of the most effective dental caries prevention methods. To continuously prevent dental caries, stably immobilizing the fluoride on the tooth enamel is highly desirable. This study aimed to evaluate the remineralization of tooth enamels by one-pot coating using polydopamine and fluoride ions. METHODS: To prepare the enamel specimens for polydopamine- and fluoride ion-coating, they were treated with polydopamine- and fluoride-containing gels. The enamel specimens were collected from human molars in a blind manner (n = 100) and were randomized into five treatment groups (n = 20, each): 1) untreated, 2) polydopamine-coated, 3) fluoride-containing gel-treated, 4) F varnish-treated, and 5) polydopamine- and fluoride ion-coated enamels. Vickers hardness number (VHN), morphology, and fluoride contents of the specimens were measured before and after the pH-cycling regimen. RESULTS: Polydopamine- and fluoride ion-coated enamels showed the highest fluoride content and lowest VHN reduction among the samples. The fluoride content of the polydopamine/fluoride ion (PD/F)-coated enamel was increased to 182 ± 6.6%, which was far higher than that of the uncoated enamel (112.3 ± 32.8%, P < 0.05). The changes in the VHN values (ΔVHN) of PD/F-coated enamel substrates showed a slight reduction in the VHN (-3.6%, P < 0.05), which was far lower than that in the control group (-18.9%, P < 0.05). In addition, scanning electron microscopy clearly supported the effect of polydopamine- and fluoride ion-coatings on the remineralization of enamel specimens. CONCLUSION: Our findings suggest that one-pot treatments with polydopamine and fluoride ions could significantly enhance remineralization by inhibiting enamel demineralization through the prolonged retention of fluoride ions.

Monoradiculopathy-induced abdominal pseudohernia caused by T11-12 soft disc herniation: a case report and literature review.

BACKGROUND: An abdominal pseudohernia is a rare clinical entity that consists of an abnormal bulging of the abdominal wall that can resemble a true hernia but does not have an associated underlying fascial or muscle defect. Abdominal pseudohernia is believed to result from denervation of the abdominal muscles in cases of herpes zoster infection, diabetes mellitus, lower thoracic or upper lumbar disc herniation, surgical injuries, and rib fracture. To date, nine cases of abdominal pseudohernia caused by disc herniation at the lower thoracic or upper lumbar levels have been reported. CASE PRESENTATION: A 35-year-old man with no underlying disease or traumatic event presented with chief complaints of left flank pain and a protruding left lower abdominal mass that had formed one day earlier. There was no true abdominal hernia on abdominal computed tomography (CT), although CT and magnetic resonance imaging (MRI) showed a herniated soft (non-calcified) disc into the left neural foramen at the T11-12 level. A nonsteroidal anti-inflammatory drug was prescribed for the flank pain, and the patient was followed on a regular basis for six months. Follow-up MRI taken at the last visit showed complete resorption of the herniated disc. Abdominal pseudohernia and flank pain were also completely resolved. CONCLUSION: We report a rare case of monoradiculopathy-induced abdominal pseudohernia caused by foraminal soft disc herniation at the T11-12 level. In patients who have an abdominal pseudohernia without herpes zoster infection, diabetes mellitus, or traumatic events, lower thoracic disc herniations should be included in differential diagnosis.

Recanalization of external iliac artery occlusion in a patient with spinal stenosis using medications: a case report.

BACKGROUND: Iliac artery occlusion accompanied by spinal canal stenosis is rare. All reported cases were treated with endovascular stenting for iliac artery occlusion. We report the first case of external iliac artery occlusion accompanied by spinal stenosis, which was successfully treated with conservative treatment. CASE PRESENTATION: A 66-year-old man with lower extremity pain and claudication visited the outpatient spine clinic. He complained of a tingling sensation in the L5 dermatome of the right leg and L4 dermatome of the left leg. Magnetic resonance imaging showed central stenosis in at the L4-5 and L5-S1 levels, and lateral recess stenosis at the L5-S1 level. The patient's symptoms were ambiguous with mixed neurological claudication and vascular claudication. Computed tomography of the lower extremity artery showed complete occlusion in the right external iliac artery. Conservative treatment with clopidogrel and beraprost sodium was performed. After treatment, his symptoms gradually improved. Clopidogrel and beraprost sodium were continued for 4 years. Follow-up computed tomography at 4 years showed recanalization of the right external iliac artery occlusion. CONCLUSIONS: We describe a rare case of external iliac artery occlusion and spinal stenosis. External iliac artery occlusion may be successfully treated only with conservative treatment using medication.

Effect of Lumbar Spinal Stenosis on Treatment of Osteoporosis: Comparison of Three Oral Bisphosphonate Therapies.

(1) Background: Lumbar spinal stenosis (LSS) causes uncomfortable neuropathic symptoms, which can negatively affect osteoporosis. The aim of this study was to investigate the effect of LSS on bone mineral density (BMD) in patients treated with one of three oral bisphosphonates (ibandronate, alendronate and risedronate) for initially diagnosed osteoporosis. (2) Methods: We included 346 patients treated with oral bisphosphonates for three years. We compared annual BMD T-scores and BMD increases between the two groups according to symptomatic LSS. The therapeutic efficacies of the three oral bisphosphonates in each group were also evaluated. (3) Results: Annual and total increases in BMD were significantly greater in group I (osteoporosis) compared to group II (osteoporosis + LSS). The total increase in BMD for three years was significantly greater in the ibandronate and alendronate subgroups than that in the risedronate subgroup (0.49 vs. 0.45 vs. 0.25, p < 0.001). Ibandronate showed a significantly greater increase in BMD than that of risedronate in group II (0.36 vs. 0.13, p = 0.018). (4) Conclusions: Symptomatic LSS may interfere with the increase in BMD. Ibandronate and alendronate were more effective in treating osteoporosis than risedronate. In particular, ibandronate was more effective than risedronate in patients with both osteoporosis and LSS.

Carbon black-containing self-healing adhesive hydrogels for endoscopic tattooing.

Endoscopic tattooing with India ink is a popular method for identifying colonic lesions during minimally invasive surgery because it is highly challenging to localize lesions during laparoscopy. However, there is a perceived unmet need for the injection of India ink and carbon particle suspension due to various complications and inconstant durability during the perioperative period. In this study, carbon black-containing self-healing adhesive alginate/polyvinyl alcohol composite hydrogels were synthesized as endoscopic tattooing inks. Alginate (Alg) conjugated with phenylboronic acid (PBA) groups in the backbone was crosslinked with polyvinyl alcohol (PVA) because of the dynamic bonds between the phenylboronic acid in alginate and the cis-diol groups of PVA. The carbon black-incorporated Alg-PBA/PVA hydrogels exhibited self-healing and re-shapable properties, indicating that improved intraoperative localization could be achieved. In addition, the adhesive tattooing hydrogels were stably immobilized on the target regions in the intraperitoneal spaces. These carbon black-containing self-healing adhesive hydrogels are expected to be useful in various surgical procedures, including endoscopic tattooing.

An all-arthroscopic surgery technique for snapping popliteal tendon syndrome: A case report and literature review.

RATIONALE: The incidence of snapping popliteus tendon syndrome, a type of lateral knee snapping, is not high, so making an accurate diagnosis is difficult. A proper treatment following an accurate diagnosis is essential for improvement. Very few cases have been reported of its treatment. PATIENT CONCERNS: An 18-year-old male patient had experienced painful popping in the lateral part of the knee during knee flexion for 3 years before his hospital visit. DIAGNOSES: Snapping popliteus tendon syndrome. INTERVENTIONS: The patient underwent an all-arthroscopic surgery. Tendon debulking and tissue debridement around the popliteus tendon was conducted, but the snapping did not resolve. The enlarged tubercle was excised through an arthroscopic procedure using a burr, and the surgery was finished after confirming that snapping was resolved. OUTCOMES: Full range of motion (ROM) was recovered 6 weeks after surgery and the snapping did not recur. LESSONS: Snapping popliteus tendon syndrome is a disease that is hardly recognized due to its low prevalence and difficulty in diagnosis, and it requires close observation of the patient before surgery. The location of the tenderness and the snapping occurrence must also be carefully identified. Our procedure is an entirely arthroscopic technique; as it has the prominent advantage of a speedy recovery and easy rehabilitation, it could also be helpful to set treatment standards for this disease in the future.

Self-Disclosure and Post-traumatic Growth in Korean Adults: A Multiple Mediating Model of Deliberate Rumination, Positive Social Responses, and Meaning of Life.

Background: To explore how self-disclosure leads to post-traumatic growth (PTG) in adults who have experienced traumatic events, this study identified the relationship between self-disclosure and post-traumatic growth in Korean adults. We examined a parallel multiple mediating model for this relationship. Methods: Participants were 318 Korean male and female adult participants aged 20 years or older who had experienced trauma. We measured deliberate rumination, positive social responses, and the meaning of life as mediating variables. Results: The results revealed that the study variables positively correlated with PTG. Self-disclosure was positively correlated with deliberate rumination, positive social responses, and meaning of life. In the multiple mediating model, deliberate rumination, positive social responses, and meaning of life mediated the relationship between self-disclosure and PTG. Conclusion: Self-disclosure, deliberate rumination, positive social responses, and meaning of life play an important role in the growth of adults who have experienced traumatic events. The findings of this study should provide valuable information for future research and for mental health professionals who want to promote the PTG of their clients.

PPARα-ACOT12 axis is responsible for maintaining cartilage homeostasis through modulating de novo lipogenesis.

Here, in Ppara-/- mice, we found that an increased DNL stimulated the cartilage degradation and identified ACOT12 as a key regulatory factor. Suppressed level of ACOT12 was observed in cartilages of OA patient and OA-induced animal. To determine the role and association of ACOT12 in the OA pathogenesis, we generated Acot12 knockout (KO) (Acot12-/-) mice using RNA-guided endonuclease. Acot12-/- mice displayed the severe cartilage degradation with the stimulation of matrix MMPs and chondrocyte apoptosis through the accumulation of acetyl CoA. Delivery of acetyl CoA-conjugated chitosan complex into cartilage stimulated DNL and cartilage degradation. Moreover, restoration of ACOT12 into human OA chondrocytes and OA-induced mouse cartilage effectively rescued the pathophysiological features of OA by regulating DNL. Taken together, our study suggested ACOT12 as a novel regulatory factor in maintaining cartilage homeostasis and targeting ACOT12 could contribute to developing a new therapeutic strategy for OA.

Molecularly Tailored Interface for Long-Term Xenogeneic Cell Transplantation.

Encapsulation of therapeutic cells in a semipermeable device can mitigate the need for systemic immune suppression following cell transplantation by providing local immunoprotection while being permeable to nutrients, oxygen, and different cell-secreted biomolecules. However, fibrotic tissue deposition around the device has been shown to compromise the long-term function of the transplanted cells. Herein, a macroencapsulation device design that improves long-term survival and function of the transplanted cells is reported. The device is comprised of a semipermeable chitosan pouch with a tunable reservoir and molecularly engineered interface. The chitosan pouch interface decorated with 1,12-dodecanedioic acid (DDA), limits the cell adhesion and vigorous foreign body response while maintaining the barrier properties amenable to cell encapsulation. The device provides long-term protection to the encapsulated human primary hepatocytes in the subcutaneous space of immunocompetent mice. The device supports the encapsulated cells for up to 6 months as evident from cell viability and presence of human specific albumin in circulation. Solutions that integrate biomaterials and interfacial engineering such as the one described here may advance development of easy-to manufacture and retrievable devices for the transplantation of therapeutic cells in the absence of immunosuppression.

Self-Healing of Hyaluronic Acid to Improve In Vivo Retention and Function.

Convergent advances in the field of soft matter, macromolecular chemistry, and engineering have led to the development of biomaterials that possess autonomous, adaptive, and self-healing characteristics similar to living systems. These rationally designed biomaterials can surpass the capabilities of their parent material. Herein, the modification of hyaluronic acid (HA) to exhibit self-healing properties is described, and its physical and biological function both in vitro and in vivo is studied. The in vitro findings showed that self-healing HA designed to undergo self-repair improves lubrication, enhances free radical scavenging, and attenuates enzymatic degradation compared to unmodified HA. Longitudinal imaging following intraarticular injection of self-healing HA shows improved in vivo retention despite its low molecular weight. Concomitant with these functions, intraarticular injection of self-healing HA mitigates anterior cruciate ligament injury-mediated cartilage degeneration in rodents. This proof-of-concept study shows how incorporation of functional properties such as self-healing can be used to surpass the existing capabilities of biolubricants.

Rapidly progressive gas-forming infection involving the spine as a life-threatening fatal condition : a case report.

BACKGROUND: Gas forming infection of the spine is a consequence of vertebral osteomyelitis, necrotizing fasciitis, or a gas-forming epidural abscess, which is very rare and fatal conditions. This is the rare case of necrotizing fasciitis that rapidly progressed from the lumbar area to upper thoracic area. CASE PRESENTATION: A 58-year-old male complained of lower back pain with fever and chills. The patient had a history of uncontrolled diabetes mellitus without diabetic medication over the previous 3 months, and he had received several local injections around the lumbar area. Laboratory data revealed white blood cell count of 19,710 /mm3, erythrocyte sedimentation of 40 mm/h, and C-reactive protein of 30.7 mg/L. Radiological findings revealed a small amount of air bubbles in the paraspinal area and lumbar epidural spaces. The patient refused emergency surgery and was discharged from the hospital. The patient re-visited the emergency department two days after discharge complaining of more severe back pain with persistent fever, and his vital signs had deteriorated, with low blood pressure and tachycardia. K. pneumoniae was isolated in cultures from ultrasound-guided aspirates and peripheral blood. The follow-up radiographs revealed aggressive dissemination of innumerable air bubbles from the lumbar area to the T5 level. The patient underwent emergent decompressive laminectomy and debridement of infected paravertebral fascia and musculature. Despite intensive care for deteriorated vital signs and his back wound, the patient died on postoperative day 3 due to multi-organ failure. CONCLUSIONS: Necrotizing fasciitis involving the spine is a very rare disease with life-threatening conditions, rapid progression, and a high mortality rate. Therefore, prompt surgical treatment with a high index of suspicion is imperative to prevent potentially fatal conditions in similar extremely rare cases.