Mn2+-activated dual-wavelength emitting materials toward wearable optical fibre temperature sensor.

Photothermal sensing is crucial for the creation of smart wearable devices. However, the discovery of luminescent materials with suitable dual-wavelength emissions is a great challenge for the construction of stable wearable optical fibre temperature sensors. Benefiting from the Mn2+-Mn2+ superexchange interactions, a dual-wavelength (530/650 nm)-emitting material Li2ZnSiO4:Mn2+ is presented via simple increasing the Mn2+ concentration, wherein the two emission bands have different temperature-dependent emission behaviours, but exhibit quite similar excitation spectra. Density functional theory calculations, coupled with extended X-ray absorption fine structure and electron-diffraction analyses reveal the origins of the two emission bands in this material. A wearable optical temperature sensor is fabricated by incorporating Li2ZnSiO4:Mn2+ in stretchable elastomer-based optical fibres, which can provide thermal-sensitive emissions at dual- wavelengths for stable ratiometric temperature sensing with good precision and repeatability. More importantly, a wearable mask integrated with this stretchable fibre sensor is demonstrated for the detection of physiological thermal changes, showing great potential for use as a wearable health monitor. This study also provides a framework for creating transition-metal-activated luminescence materials.

VEGF-PLGA controlled-release microspheres enhanced angiogenesis in encephalomyosynangiosis-based chronic cerebral hypoperfusion.

Treatments enhancing angiogenesis for chronic cerebral hypoperfusion (CCH) are still in the research stage. Although encephalomyosynangiosis (EMS) is a common indirect anastomosis for the treatment of CCH, the effectiveness to promote angiogenesis is not satisfactory. Vascular endothelial growth factors (VEGF) is a cytokine found to specifically act directly on vascular endothelial cells, promote neovascularization, and enhance capillary permeability. However, the short half life and unstable property of VEGF underlies the need to explore available delivery system. In this study, poly (lactide-co-glycolide) (PLGA) was used to prepare VEGF controlled-release microspheres. In vitro and in vivo analysis of release kinetics showed that the microspheres could release VEGF continuously within 30 days. Then, modified chronic cerebral hypoperfusion rat model was established by ligation of bilateral internal carotid artery and one vertebral artery. At 14 days after ischemia, the EMS and the VEGF microspheres injection were performed. At 30 days after the injection, the result of Morris water maze displayed that combinating VEGF microspheres and EMS significantly ameliorated cognitive deficit after ischemia. We observed that combinating VEGF microspheres and EMS could further significantly increase cerebral blood flow. We speculated that this enhancement of cerebral blood flow was attributed to more angiogenesis induced by combination of VEGF microspheres and EMS, which verified by more collateral circulation with cerebral angiography and higher expression of CD31 or α-SMA. Our study demonstrated that combinating VEGF-PLGA controlled-release microspheres could significantly promote angiogenesis in EMS-based CCH rats model, providing new ideas for clinical treatment of CCH.

Large retrospective study of artificial dura substitute in patients with traumatic brain injury undergo decompressive craniectomy.

Background: Decompressive craniectomy is widely used for treating patients with traumatic brain injury (TBI). Usually patients have dura mater defect due to surgery or injury itself. The defective area may left open or repaired by artificial dura substitutes. A variety of artificial dura substitutes have been used for this purpose. Objective: This study aimed to evaluate bovine-derived pericardium membrane as artificial dural material for patients with decompressive craniectomy. Methods: Totally 387 patients with severe TBI in our hospital were included in this study. Among them, 192 patients were treated with standard decompressive craniectomy without dura repair (control group). One hundred and ninety-five TBI patients were treated with dura repair by artificial dura materials (ADM). Nonlyophilized bovine pericardium membranes were used as artificial dura material. The postoperative complications were compared in both groups, including infection, seizure, and cerebrospinal fluid (CSF) leakage. Results: Patients in control group have higher complication rates than patients in ADM group, including subcutaneous hematoma (13.02% in control vs. 4.01% in ADM group, p = .004), infection (12.5% in control vs. 5.64% in ADM group, p = .021), CSF leakage (13.02% in control vs. 5.13% in ADM group, p = .012), and seizure (10.42% in control vs. 3.08% in ADM group, p = .007). Patients in ADM group are only associated with higher incidence of foreign body reaction (6 of 195 patients in ADM vs. none from control group). Conclusion: Bovine-derived pericardium membranes are successfully used as artificial dural substitutes for decompressive craniectomy. Patients with ADM have better clinical outcome than control group.

Strategy of Metal-Polymer Composite Stent To Accelerate Biodegradation of Iron-Based Biomaterials.

The new principle and technique to tune biodegradation rates of biomaterials is one of the keys to the development of regenerative medicine and next-generation biomaterials. Biodegradable stents are new-generation medical devices applied in percutaneous coronary intervention, etc. Recently, both corrodible metals and degradable polymers have drawn much attention in biodegradable stents or scaffolds. It is, however, a dilemma to achieve good mechanical properties and appropriate degradation profiles. Herein, we put forward a metal-polymer composite strategy to achieve both. Iron stents exhibit excellent mechanical properties but low corrosion rate in vivo. We hypothesized that coating of biodegradable aliphatic polyester could accelerate iron corrosion due to the acidic degradation products, etc. To demonstrate the feasibility of this composite material technique, we first conducted in vitro experiments to affirm that iron sheet corroded faster when covered by polylactide (PLA) coating. Then, we fabricated three-dimensional metal-polymer stents (MPS) and implanted the novel stents in the abdominal aorta of New Zealand white rabbits, setting metal-based stents (MBS) as a control. A series of in vivo experiments were performed, including measurements of residual mass and radial strength of the stents, histological analysis, micro-computed tomography, and optical coherence tomography imaging at the implantation site. The results showed that MPS could totally corrode in some cases, whereas iron struts of MBS in all cases remained several months after implantation. Corrosion rates of MPS could be easily regulated by adjusting the composition of PLA coatings.

Recent advances on smart TiO2 nanotube platforms for sustainable drug delivery applications.

To address the limitations of traditional drug delivery, TiO2 nanotubes (TNTs) are recognized as a promising material for localized drug delivery systems. With regard to the excellent biocompatibility and physicochemical properties, TNTs prepared by a facile electrochemical anodizing process have been used to fabricate new drug-releasing implants for localized drug delivery. This review discusses the development of TNTs applied in localized drug delivery systems, focusing on several approaches to control drug release, including the regulation of the dimensions of TNTs, modification of internal chemical characteristics, adjusting pore openings by biopolymer coatings, and employing polymeric micelles as drug nanocarriers. Furthermore, rational strategies on external conditions-triggered stimuli-responsive drug release for localized drug delivery systems are highlighted. Finally, the review concludes with the recent advances on TNTs for controlled drug delivery and corresponding prospects in the future.

Microvascular Decompression for Hemimasticatory Spasm: A Case Report and Review of the Literature.

BACKGROUND: Hemimasticatory spasm is a rare clinical entity characterized by involuntary and paroxysmal contractions of the jaw-closing muscles on 1 side of the face. Although its cause is not fully known, vascular compression of the trigeminal nerve has been speculated. CASE DESCRIPTION: Here, we report 1 case of hemimasticatory spasm that was cured by microvascular decompression of the motor branch of the trigeminal nerve; a relevant literature review was also performed. CONCLUSIONS: Hemimasticatory spasm is a rare disease that may be recalcitrant to conservative medical therapy, and vascular decompression of the trigeminal nerve may be required to relieve the spasm.

TiO2 nanotube platforms for smart drug delivery: a review.

Titania nanotube (TNT) arrays are recognized as promising materials for localized drug delivery implants because of their excellent properties and facile preparation process. This review highlights the concept of localized drug delivery systems based on TNTs, considering their outstanding biocompatibility in a series of ex vivo and in vivo studies. Considering the safety of TNT implants in the host body, studies of the biocompatibility present significant importance for the clinical application of TNT implants. Toward smart TNT platforms for sustainable drug delivery, several advanced approaches were presented in this review, including controlled release triggered by temperature, light, radiofrequency magnetism, and ultrasonic stimulation. Moreover, TNT implants used in medical therapy have been demonstrated by various examples including dentistry, orthopedic implants, cardiovascular stents, and so on. Finally, a future perspective of TNTs for clinical applications is provided.

Haemostatic efficacy of an ethyl-2-cyanoacrylate-based aerosol in combination with tourniquet application in a large wound model with an arterial injury.

BACKGROUND: Tourniquet application is the standard method for the control of severe trauma haemorrhage. However, it may result in severe ischaemic injuries when used for a long time. In this study, we developed a modified ethyl-2-cyanoacrylate-based aerosol (ECA) aerosol spray and determined its efficacy for short-time control of bleeding of large wounds in pigs when used in combination with tourniquet application. METHODS: A large wound model with a femoral arterial injury was made in the middle of either thigh of the pig. Thirty white female hybrid pigs were divided evenly and randomly into three groups, including tourniquet application only group (group A), tourniquet-ECA group (group B, a combination of ECA with tourniquet application) and tourniquet-ECA with wound cleaning group (group C, a combination of ECA with tourniquet application plus wound cleaning). RESULTS: The success rates of haemostasis were 0%, 30%and 90% in groups A, B and C, respectively (P<0.05). The incidence of haematoma and the membrane forming time were 100% and 20%, and 5.9+/-1.0min and 8.3+/-1.1min, respectively, in groups B and C (both P<0.05). The haemostatic time and the thickness of membrane were 11.9+/-1.8min and 10.2+/-1.4min, and 0.68+/-0.29mm and 0.79+/-0.25mm, respectively, in the two groups (P>0.05, both). CONCLUSION: The ECA spray achieves haemostasis within a very short time when it is used in combination with tourniquet application in a large wound model with an arterial injury. It may effectively prevent the wound from bleeding without the need for any long-term pressure bandage to wrap the wound, and it is easy to be disposed in debridement. Therefore, it may serve as an optimal choice for the first aid of large wounds with an arterial injury.