Development of Polyphosphate/Nanokaolin-Modified Alginate Sponge by Gas-Foaming and Plasma Glow Discharge Methods for Ultrarapid Hemostasis in Noncompressible Bleeding.

Effective bleeding management strategies in uncontrollable and noncompressible massive hemorrhage are becoming important in both clinical and combat situations. Here, a novel approach was developed to create a superporous and highly absorbable hemostatic sponge through a facile chemical gas-foaming method by cross-linking long-chain polyphosphate along with nanokaolin and Ca2+ in an alginate structure to synergistically activate the coagulation pathway. Natural kaolin obtained from the Marand mine in East Azarbaijan was converted into pseudohexagonal-shaped kaolin nanoparticles (30 to 150 nm) using ball milling followed by a newly developed glow discharge plasma treatment method. The obtained ultralight sponges (>90% porosity) exhibit ultrarapid water/blood absorption capacity (∼4000%) and excellent shape memory, which effectively concentrates coagulation factors. The results of in vitro tests demonstrated that the proposed sponges exhibited enhanced blood clotting ability (BCI < 10%) and superior cohesion with red blood cells (∼100) and platelets (∼80%) compared to commercially available hemostatic products. The in vivo host response results exhibited biosafety with no systemic and significant local inflammatory response by hematological, pathological, and biochemical parameter assessments. In a rat femoral artery complete excision model, the application of alginate/k/polyp nanocomposite sponges resulted in a complete hemostasis time of 60 s by significant reduction of hemostasis time (∼6.7-8.3 fold) and blood loss (∼2-2.8-fold) compared to commercially available hemostatic agents (P < 0.001). In conclusion, distinct physical characteristics accompanied by unique chemical composition multifunctional sponges activate hemostasis synergistically by triggering the XII, XI, X, IX, V, and II factors and the contact pathway and have the ability of rapid hemostasis in noncompressible severe bleeding.

Chelating ZnO-dopamine on the surface of graphene oxide and its application as pH-responsive and antibacterial nanohybrid delivery agent for doxorubicin.

In this work, a new pH-responsive nanohybrid carrier was prepared with chelating ZnO-dopamine (Zn-d) on the surface of graphene oxide. Doxorubicin (DOX) as a model drug was loaded on the resulted nanohybrid. The characteristics of Zn-d-rGO nanohybrid (NH) determined using Fourier transformed infrared spectroscopy (FT-IR), X-ray Diffraction spectroscopy (XRD), UV-Visible spectroscopy, Scanning Electron Microscope (SEM), EDX and AFM. The BET analysis showed a specific surface area of 37.16 m2/g and the obtained nanohybrid indicated a high loading capacity of DOX up to 99.7%, and the release profile displayed a pH-dependent discharge in the acidic environment for14 days. The cytotoxicity of the prepared nanohybrid was measured against T47D and MCF10A cells and it confirmed that as-prepared nanohybrid has high toxicity against cancer cells and lower effect against human breast cell. Meanwhile, the prepared nanohybrids showed well antimicrobial activity against gram-positive and negative bacteria. The obtained results showed that the prepared nanohybrid (Zn-d-rGO) could potentially be used as a safe carrier for drug delivery systems.

Outbreak of Hospital Infection from Biofilm-embedded Pan Drug-resistant Pseudomonas aeroginosa, Due to a Contaminated Bronchoscope.

Background: Colistin-resistant Pseudomonas aeruginosa (P. aeruginosa) has been defined as pandrug-resistant (PDR) strain. Outbreaks of PDR P. aeruginosa especially in pulmonary tract infections due to contaminated bronchoscopes have rarely been reported. The emergence of pandrug-resistant strains in both CF (Cystic Fibrosis) and non-CF clinical isolates over recent years remains of a great concern. Hospital wards contaminated with PDR P. aeruginosa infection, must be shot down until their eradication. Health Authorities must be informed immediately and infection control strategies must be implemented. Aim: To report such an outbreak and modify the infection control strategy in an academic hospital in Ankara Turkey. Methods: From October to December 2013, PDR-Pseudomonas aerogionsa were identified from bronchial cultures of 15 patients who had undergone bronchoscopy prior to the infection. Three batches of surveillance cultures were obtained from the environmental objects and healthcare workers related to the procedures. Pulsed-field gel electrophoresis (PFGE) was used for bacterial typing. Antimicrobial susceptibility was assessed by disc diffusion and E-test methods. Findings: A total of 70 specimens were obtained during the first surveillance operation. One Colistin-resistant P. aeroginosa was isolated from a bronchoscope. Although the disinfection protocols for bronchoscope were revised and implemented, seven additional bronchial cases were identified thereafter. The pathogen was identified from two subsequent surveillance cultures and was not eliminated until Ethylene oxide sterilization was added to the disinfection protocol. PFGE revealed that all 15 isolates from the patients and the three isolates from the bronchoscope shared a common pattern with minor variance. XbaI restriction enzyme turned out better than SpeI in interpreting bacterial pulse types with BioNumerics 6.0. The most suitable cut off value for SpeI was above 80% Dice similarity while for XbaI above 95%Dice similarity with BioNumerics 6.0. Conclusion: The outbreak of "Colistin" pan drug-resistant Pseudomonas aeroginosa was caused by a contaminated bronchoscope and was terminated by the implementation of a revised disinfection protocol for bronchoscope.