Ag/alginate nanofiber membrane for flexible electronic skin.

Flexible electronic skin has stimulated significant interest due to its widespread applications in the fields of human-machine interactivity, smart robots and health monitoring. As typical elements of electrical skin, the fabrication process of most pressure sensors combined nanomaterials and PDMS films are redundant, expensive and complicated, and their unknown biological toxicity could not be widely used in electronic skin. Hence, we report a novel, cost-effective and antibacterial approach to immobilizing silver nanoparticles into-electrospun Na-alginate nanofibers. Due to the unique role of carboxyl and hydroxyl groups in Na-alginate, the silver nanopaticles with 30 nm size in diameter were uniformly distributed inside and outside the alginate nanofibers, which obtained pressure sensor shows stable response, including an ultralow detection limited (1 pa) and high durability (>1000 cycles). Notably, the pressure sensor fabricated by these Ag/alginate nanofibers could not only follow human respiration but also accurately distinguish words like 'Nano' and 'Perfect' spoke by a tester. Interestingly, the pixelated sensor arrays based on these Ag/alginate nanofibers could monitor distribution of objects and reflect their weight by measuring the different current values. Moreover, these Ag/alginate nanofibers exhibit great antibacterial activity, implying the great potential application in artificial electronic skin.

[Two techniques of posterior chamber intraocular lens (IOL) implantation by a 4-point ciliary sulcus suture fixation technique combined with vitrectomy].

OBJECTIVE: To observe the results of two techniques of posterior chamber intraocular lens (IOL) implantation by a 4-point ciliary sulcus suture fixation combined with vitrectomy. METHODS: Lensectomy and vitrectomy combined with posterior chamber IOL implantation by a 4-point scleral fixation was performed in 23 cases with complicated ocular trauma, including 9 eyes had eyeball rupture, vitreous hemorrhage, retinal contusion and traumatic cataract; 6 eyes having eyeball rupture, vitreous hemorrhage, retinal contusion, intraocular foreign body and traumatic cataract; 8 eyes having ocular blunt trauma, vitreous hemorrhage, traumatic cataract and lens dislocation. Two techniques of IOL were randomly assigned: Alcon CZ70BD PMMA suspensory IOL was performed in 12 cases (Group I); Bausch & Lomb Akreos Adapt four-haptic hydrophilic acrylic foldable IOL was performed in 11 cases (Group II). After completed vitrectomy, removed intraocular foreign body and (or) cataract extracted, one-stage IOL implantation by 4-point scleral fixation was performed and the knots of fixation sutures were rotated and buried under the sclera for all patients. The IOL position was adjusted by suture for the best centration. RESULT: The mean follow-up time was (12.4 +/-1.7) months. The postoperative best-corrected visual acuity (BCVA) was improved in 11 cases (91.7%) of Group I; and BCVA was > or =0.5 in 3 patients(25.0 %). The postoperative BCVA was improved in 11 cases (100 %) of Group II; and BCVA was > or =0.5 in 4 eyes (36.4%). There was no IOL decentration or tilting in two groups. CONCLUSION: Lensectomy and vitrectomy combined with posterior chamber IOL implantation by a 4-point scleral fixation technique is a good method to treat complicated ocular trauma. Two techniques of posterior chamber IOL have both advantages and disadvantages, and can be used accordingly.

In situ accurate deposition of electrospun medical glue fibers on kidney with auxiliary electrode method for fast hemostasis.

An auxiliary electrode electrospinning method is proposed to deposit N-octyl-2-cyanoacrylate (NOCA) medical glue fibrous membrane on kidney for in-situ fast hemostasis. A metal electrode equipped to the spinning needle is used to confine the divergence angle of jet. Compared to the conventional electrospinning method, the fiber deposition area has reduced by 2.5 times, and it can achieve in-situ accurate deposition. Moreover, it reduces both the external dimension and over-reliance on electricity, which is superior to previous air-flow assisted electrospinning method. In addition, in situ accurate deposition of NOCA on the kidney exhibits fast hemostasis within 10 s, confirming that this auxiliary electrode method can be applied in outdoors for fast hemostasis. Further pathological studies indicate that this auxiliary electrode method can reduce the inflammatory response of tissues due to the better accurate deposition. This portable hand-held device with the auxiliary electrode method may have potential application in fast hemostasis for outdoors due to its accurate deposition and portability characteristics.

Electric- Field-Modified In Situ Precise Deposition of Electrospun Medical Glue Fibers on the Liver for Rapid Hemostasis.

Precise deposition of nanofibers is still an important issue in the applications of electrospinning (e-spinning), especially in rapid hemostasis of organs such as the liver, lung, and kidney. In this study, we propose an electric field-modified e-spinning technique with a metal cone attached to the spinning nozzle to realize controllable precise deposition of fibers. The deposition range of the e-spun fibers is tunable by changing the size of the metal cone, and the mechanism is attributed the focused electric field verified by theoretical simulations. This electric field-modified e-spinning method was further used to in situ precisely deposit medical glue N-octyl-2-cyanoacrylate (NOCA) fibers onto the resection site of rat liver to realize rapid hemostasis within 10 s. Postoperative pathological results indicate that less inflammatory response and tissue adhesion are observed in this electric field-modified e-spinning group compared with that of traditional airflow-assisted group. This technique combined with our designed handheld e-spinning device could be used in emergency medical treatment, clinics, field survival, and home care for its portability and precise deposition characteristics.

Electric Field-Assisted In Situ Precise Deposition of Electrospun γ-Fe2O3/Polyurethane Nanofibers for Magnetic Hyperthermia.

A facial electrospinning method of in situ precise fabricating magnetic fibrous membrane composed of polyurethane (PU) nanofibers decorated with superparamagnetic γ-Fe2O3 nanoparticles with simultaneous heat generation in response to alternating magnetic field (AMF) is reported. In this method, a conical aluminum auxiliary electrode is used to regulate the electrostatic field and affect the process of electrospinning for the in situ rapid and precise deposition of electrospun γ-Fe2O3/PU fibers. The auxiliary conical electrode can extend the jet stabilization zone of the precursor solution four times longer than that of without auxiliary electrode, which can achieve the precise control of the fiber deposition area. Moreover, the electrospun composite fibrous membranes show a rapid temperature increase from room temperature to 43 °C in 70 s under the AMF, which exhibits faster heating rate and higher heating temperature compared to the samples fabricated without the assist of the auxiliary electrode. The present results demonstrate that the in situ precise electrospinning with the help of an auxiliary conical electrode has the potential as a manipulative method for preparing magnetic composite fibers as well as magnetic hyperthermia of cancer therapy.

Rigid gas-permeable contact lens for visual rehabilitation in aphakia following trauma.

PURPOSE: The aim here was to study the safety and efficacy of fitting a rigid gas-permeable contact lens (RGP CL) for visual rehabilitation in patients with ocular trauma. METHODS: A retrospective study was performed on 17 aphakic eyes of patients (16 men and one woman) after surgery for ocular trauma. RGP CLs (including nine brown-tinted lenses) were fitted unilaterally for visual rehabilitation in these patients. The uncorrected vision, spectacle visual acuity and contact lens (CL) visual acuity were recorded. RESULTS: Seventeen patients were selected on the basis that they had undergone surgery following ocular trauma. All eyes fitted were aphakic (n = 17) and nine eyes were fitted with brown-tinted RGP lenses to compensate for traumatic aniridia. All eyes were fitted with RGP CL. A visual acuity of 6/20 or better was seen in seven eyes (41.2 per cent) with spectacle correction and in 15 eyes (88.2 per cent) with CL correction. A visual acuity of 6/12 or better was seen in four eyes (23.5 per cent) and 10 eyes (58.8 per cent), respectively. CONCLUSIONS: A RGP CL is one of the methods available for treating refractive abnormalities in traumatic unilateral aphakia. The procedure is effective, safe and tolerable. RGP CLs can correct the vision of patients with irregular corneal astigmatism. The brown-tinted RGP CL can improve the symptoms of photophobia and the cosmetic appearance of brown eyes.