Abstract
Inherent to any stenting procedure is the prescription of dual antiplatelet therapy (DAPT) to reduce the platelet response. Clinical guidelines recommend 6–12 months of DAPT, depending on ...stent type, clinical picture and patient factors. Our hypothesis is that a nanostructured noble metal coating has the potential to reduce protein deposition and platelet activation. These effects would reduce subsequent thrombo-inflammatory reactions, potentially mitigating the need for an extensive DAPT in the acute phase. Here, a noble metal nanostructure coating on stents is investigated. Twelve pigs underwent endovascular implantation of coated and non-coated stents for paired comparisons in a blinded study design. The non-coated control stent was placed at the contralateral corresponding artery. Volumetric analysis of angiographic data, performed by a treatment blinded assessor, demonstrated a significant thrombus reduction for one of the coatings compared to control. This effect was already seen one hour after implantation. This finding was supported by in vitro data showing a significant reduction of coagulation activation in the coated group. This novel coating shows promise as an implant material addition and could potentially decrease the need for DAPT in the early phases of stent implementation.
All over the world, different types of nanomaterials with a diversified spectrum of applications are designed and developed, especially in the field of nanomedicine. The great variety of ...nanoparticles (NPs), in vitro test systems and cell lines led to a vast amount of publications with conflicting data. To identify the decisive principles of these variabilities, we conducted an intercomparison study of collaborating laboratories within the German DFG Priority Program SPP1313, using well-defined experimental parameters and well-characterized NPs. The participants analyzed the in vitro biocompatibility of silica and polymer NPs on human hepatoma HepG2 cells. Nanoparticle mediated effects on cell metabolism, internalization, and inflammation were measured. All laboratories showed that both nanoparticle formulations were internalized and had a low cytotoxicity profile. Interestingly, small variations in nanoparticle preparation, cell handling and the type of culture slide influenced the nanoparticle stability and the outcomes of cell assays. The round robin test demonstrated the importance of the use of clearly defined and characterized NPs and parameters for reproducible results across laboratories. Comparative analyses of in vitro screening methods performed in multiple laboratories are absolutely essential to establish robust standard operation procedure as a prerequisite for sound hazard assessment of nanomaterials.
Catheter-associated urinary tract infections (CAUTI) are among the most frequent healthcare-associated infections in the world. They are associated with increased mortality, prolonged hospital stay ...and increased healthcare costs. The objective of this study was to evaluate the efficacy of the noble metal alloy (NMA) coated BIP Foley Catheter in preventing the incidence of symptomatic CAUTI in a large cohort of patients in India.
This multi-center, prospective study included 1000 adult patients admitted to six hospitals across India for urology, surgery and ICU requiring urethral catheterization and admission for ≥ 48 h. Patients were allocated to the NMA-coated BIP Foley Catheter group or a non-coated control catheter group, with a randomization ratio of 3:1. CAUTI surveillance was conducted at study entry, upon catheter removal, and 2 days after catheter removal. For statistical analysis, categorical data (e.g. gender) were compared using the chi-square or Fischer test, and numerical data were compared using the two-sample t-test. Associations were evaluated using logistic regression.
The incidence of symptomatic CAUTI was reduced by 69% in the BIP Foley Catheter group compared to the control group (6.5 vs 20.8 CAUTI/1000 catheter days), with an incidence rate ratio of 0.31 (95% confidence interval: 0.21-0.46; p < 0.001). A reduction in the cumulative CAUTI incidence was evident in the BIP Foley Catheter group within 3 days after catheterization; this reduction was maintained up to ~ 30 days, and the largest reductions were seen between 3 and 11 days. There were no serious adverse events related to either catheter, and the percentage of patients with ≥ 1 adverse event was significantly lower in the NMA-coated BIP Foley Catheter group than in the control group (21.6% vs. 48.4%; p = 0.001). In conclusion, the NMA-coated BIP Foley Catheter was effective in reducing CAUTI and was well tolerated, with a lower incidence of adverse events compared to the uncoated catheter. Trial registration This study was registered prospectively (28 September 2015) in the Clinical Trials Registry of India (trial number CTRI/2015/09/006220; http://ctri.nic.in/Clinicaltrials/showallp.php?mid1=12631&EncHid=&userName=bactiguard ).
In biological fluids, an adsorption layer of proteins, a “protein corona” forms around nanoparticles (NPs) largely determining their biological identity. In many interactions with NPs proteins can ...undergo structural changes. Here, we study the adsorption of insulin onto gold NPs (mean hydrodynamic particle diameter 80 ± 18 nm), focusing on the structural consequences of the adsorption process for the protein. We use surface enhanced Raman scattering (SERS) spectroscopy to study changes in the protein’s secondary structure as well as the impact on integrity and conformations of disulfide bonds immediately on the NP surface. A detailed comparison to SERS spectra of cysteine and cystine provides first mechanistic insights into the causes for these conformational changes. Potential biological and toxicological implications of these findings are also discussed.
The deliquescence behavior of ternary inorganic (ammonium sulfate and ammonium nitrate)/organic (glutaric acid and malonic acid)/water aerosol particles has been investigated at 293 K using a novel ...surface aerosol microscopy (SAM) technique. The results obtained for the deliquescence relative humidities (DRH) for particles of variable inorganic/organic contents show a eutectic behavior with the mixed particles showing deliquescence at lower DRH compared to the pure inorganic and organic components, respectively. This behavior has been quantitatively modeled using the extended aerosol inorganics (E-AIM) thermodynamic model of Clegg et al. in combination with the UNIFAC group activity approach to account for organic molecular solutes. In addition, we have investigated the crystallization behavior of supersatured and formerly deliquesced ternary solution droplets using space resolved Raman spectroscopy. It is found that such droplets produce solid particles in which the inorganic and organic phases show some spatial separation with the organic component being predominantly found at the outer part of the particle. Independent measurements of the contact angles of such ternary droplets reveal that their angles are within experimental error identical to those of the purely organic/water solutions.
When nanoparticles (NPs) come into contact with biological fluids, proteins, and other biomolecules interact with their surface. Upon exposure to biological fluids a layer of proteins adsorbs onto ...their surface, the so-called protein corona, and interactions of biological systems with NPs are therefore mediated by this corona. Here, interactions of serum albumin with silver and gold NPs were quantitatively investigated using circular dichroism spectroscopy. Moreover, surface enhanced Raman spectroscopy was used for further elucidation of protein binding to silver surfaces. The decisive role of poly(vinylpyrrolidone), coatings on the protein adsorption was quantitatively described for the first time and the influential role of the polymer coatings is discussed. Research in nanotoxicology may benefit from such molecular scale data as well as scientific approaches seeking to improve nanomedical applications by using a wide range of polymer surface coatings to optimize biological transport and medical action of NPs.
The effects of intrathecal (i.t.) application of the proposed nociceptin receptor antagonist Nphe1nociceptin(1-13)NH2 on the flexor reflex was evaluated in spinalized rats. I.t. Nphe1nociceptin ...(1-13)NH2 dose-dependently facilitated the flexor reflex with no depression. Pretreatment with 16.5 nmol of Nphe1nociceptin(1-13)NH2 prevented the development of reflex depression following 0.55 nmol i.t. nociceptin, but strongly enhance the initial excitatory effect of nociceptin. The reflex depressive effect of i.t. endomorphine-2 was not blocked by Nphe1nociceptin(1-13)NH2 pretreatment. It is concluded that Nphe1nociceptin(1-13)NH2 is a selective antagonist of the spinal receptor mediating the inhibitory action of nociceptin. It can be further suggested that the spinal inhibitory effect of nociceptin may be tonically active.
Objectives: To assess the feasibility and radicality of a combined thoracoscopic and mediastinoscopic approach to mediastinal lymphadenectomy compared to thoracoscopy only for minimally invasive ...management of early stage lung carcinoma. Methods: Prospective observational study of patients undergoing anatomical thoracoscopic lung resection for lung carcinoma in our department in 2007. Mediastinal lymphadenectomy was performed either thoracoscopically (VATS group) or by a combination of video-assisted mediastinoscopic lymphadenectomy (VAMLA) and thoracoscopy (VAMLA + VATS group). Inclusion criteria for the study were: stage Ia on CT scan, no central tumor at bronchoscopy, and no contraindications against lobectomy or segmentectomy. Results: Eighteen VAMLA + VATS and fourteen VATS patients were studied. For histology, pTNM stage, type of resection, semiquantitative assessment of the fissure and vascular dissection plane, conversions, blood loss, operation time, adverse events and drainage time, no differences between the two groups were observed. In the VATS group, there was a slight preponderance of women, and right-sided tumors. In the VAMLA + VATS group, both the number of dissected mediastinal lymph node stations (mean, 6.4 stations vs 3.6 stations) and the weight of the mediastinal specimen (median, 11.2 groups vs 5.5 groups), were significantly higher than in the VATS group (p ≪ 0.05). Conclusions: A combined approach by VATS and VAMLA improves radicality of minimally invasive mediastinal lymphadenectomy without increase in operation time, morbidity, and drainage time.
Abstract
Poly(n-butyl-cyanoacrylate)-nanocapsules filled by perfluorodecalin (PFD) are proposed as potential oxygen carriers for blood substitute. The capsule dispersion is prepared via interfacial ...polymerisation from a PFD emulsion in water which in turn is generated by spontaneous phase separation. The resulting dispersion is capable of carrying approximately 10% of its own volume of gaseous oxygen, which is approximately half of the capacity of human blood. The volumes of the organic solvents and water are varied within a wide range, connected to a change of the capsule radius between 200 and 400 nm. The principal suitability of the capsule dispersion for intravenous application is proven in first physiological experiments. A total amount of 10 ml/kg body weight has been infused into rats, with the dispersion supernatant and a normal saline solution as controls. After the infusion of nanocapsules, the blood pressure as well as the heart rate remains constant on a normal level.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK