Development of biliary stent applying the antibacterial activity of silver: A literature review

2021 ◽  
Vol 32 (2) ◽  
pp. 63-71
Author(s):  
Akane Yamabe ◽  
Atsushi Irisawa ◽  
Yasuhito Kunogi ◽  
Ken Kashima ◽  
Kazunori Nagashima ◽  
...  

BACKGROUND: Endoscopic transpapillary stenting is commonly performed in patients with obstructive jaundice caused by a biliary stricture. Although the plastic stent (PS) is widely used for biliary drainage because of the low-cost and easy procedure, patency is short after placement in the bile duct because of the small diameter. Dysfunction of PS is primarily caused by biliary sludge that forms as a result of bacterial adhesion and subsequent biofilm formation on the inner surface of the stent. It is well known that silver ions have excellent antibacterial activity against a wide range of microorganisms. OBJECTIVE: This review provides an overview and perspective of the significance of silver-coated biliary stents. METHODS: We collected literature regarding silver-coated biliary stents, reviewed the current research/development status and discussed their possible usefulness. RESULTS: To date, several in vivo/vitro studies evaluated the patency of silver-blended or silver-coated biliary stents. These studies suggested that the silver coating on a PS was likely to prolong the patency period. CONCLUSION: The development of biliary stents using silver is expected to prolong stent patency and prevent frequent stent replacement.

2020 ◽  
Author(s):  
Joost van Haasteren ◽  
Altar M Munis ◽  
Deborah R Gill ◽  
Stephen C Hyde

Abstract The gene and cell therapy fields are advancing rapidly, with a potential to treat and cure a wide range of diseases, and lentivirus-based gene transfer agents are the vector of choice for many investigators. Early cases of insertional mutagenesis caused by gammaretroviral vectors highlighted that integration site (IS) analysis was a major safety and quality control checkpoint for lentiviral applications. The methods established to detect lentiviral integrations using next-generation sequencing (NGS) are limited by short read length, inadvertent PCR bias, low yield, or lengthy protocols. Here, we describe a new method to sequence IS using Amplification-free Integration Site sequencing (AFIS-Seq). AFIS-Seq is based on amplification-free, Cas9-mediated enrichment of high-molecular-weight chromosomal DNA suitable for long-range Nanopore MinION sequencing. This accessible and low-cost approach generates long reads enabling IS mapping with high certainty within a single day. We demonstrate proof-of-concept by mapping IS of lentiviral vectors in a variety of cell models and report up to 1600-fold enrichment of the signal. This method can be further extended to sequencing of Cas9-mediated integration of genes and to in vivo analysis of IS. AFIS-Seq uses long-read sequencing to facilitate safety evaluation of preclinical lentiviral vector gene therapies by providing IS analysis with improved confidence.


Nanomaterials ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 978 ◽  
Author(s):  
Lian-Hua Fu ◽  
Qing-Long Gao ◽  
Chao Qi ◽  
Ming-Guo Ma ◽  
Jun-Feng Li

Silver-based antimicrobial nanomaterials are considered as the most promising antibacterial agents owing to their outstanding antimicrobial efficacy and their relatively low toxicity to human beings. In this work, we report on a facile and environment-friendly microwave-hydrothermal method to prepare cellulose/Ag nanocomposites using hemicellulose as the reductant. The influences of the microwave-hydrothermal heating time and temperature, as well as the hemicellulose concentration on the formation of cellulose nanocomposites, were investigated in detail. Experimental results indicated that the hemicellulose was an effective reductant for silver ions, with higher temperature and longer heating time favoring the formation of silver with higher crystallinity and mass content in the nanocomposites. Moreover, the antimicrobial properties of the as-prepared cellulose/Ag nanocomposites were explored using Gram-positive S. aureus ATCC 6538 and Gram-negative E. coli HB 101 by both disc diffusion method and agar dilution method, and the nanocomposites showed excellent antibacterial activity. These results demonstrate that the as-prepared cellulose/Ag nanocomposites, as a kind of antibacterial material, are promising for applications in a wide range of biomedical fields.


2019 ◽  
Vol 73 ◽  
pp. 182-188
Author(s):  
Sabina Galiniak ◽  
Marek Biesiadecki ◽  
Bożena Czubat ◽  
Dorota Bartusik-Aebisher

Curcumin, a compound belonging to the group of polyphenols with a characteristic yellow-orange color, is the most active ingredient of the long-leaved Curcuma longa L. and the ingredient of seasoning mixes, including curry spices. Due to its antioxidant, anti-inflammatory and anti-cancer properties, it has a wide range of therapeutic effects and has been studied for many years. Curcumin has enormous potential in preventing many diseases due to the widely described benefits of its use, it is non-toxic and additionally. Therapy with curcumin is low cost. Currently, many studies focus on the anti-glycation activity of curcumin, which could be used as an active inhibitor of glycation, i.e. a non-enzymatic process of combining a keto or aldehyde group of sugar with a free amino group of a protein. Finally, heterogeneous end products of advanced glycation are formed in the multistage and complicated glycation reaction. Formation of glycation products is intensified with age, as well as in various disease states, including diabetes or neurodegenerative diseases. Many literature data describe the role of curcumin in the prevention and treatment of diabetes. It is known that polyphenol has beneficial effects on hyperglycemia, insulin resistance and regeneration of secretory cells of pancreatic islets. It seems that addition of curcumin, the main ingredient of curry spice, to food could help people prevent the development of lifestyle diseases, including diabetes and its complications. The article presents the current state of knowledge on the curcumin anti-glycation properties in vitro as well as in vivo.


2005 ◽  
Vol 15 (03n04) ◽  
pp. 111-123 ◽  
Author(s):  
K. ISHII ◽  
S. MATSUYAMA ◽  
H. YAMAZAKI ◽  
Y. WATANABE ◽  
T. YAMAGUCHI ◽  
...  

We developed a micron-CT consisting of micro-beam system and X-ray CCD camera (Hamamatsu photonics C8800X), whose element size is 8μ m ×8μ m and a total number of image elements 1000×1000 gives an image size of 8 mm ×8 mm . The sample is placed in a tube of a small diameter, which is rotated by a stepping motor. The transmission data through the sample are taken with characteristic Ti - K -X-rays (4.558 keV) produced by 3MeV proton and α particle micro-beams. After image reconstruction using an iteration method, 3D-images of small objects namely, hair and small ants were obtained with a spatial resolution of ~5μm. It is expected that our micron-CT can provide cross sectional images of in-vivo cellular samples with high resolution and can be applied to a wide range of research in biology and medicine.


2020 ◽  
Vol 35 (6) ◽  
pp. 670-680
Author(s):  
Yaichiro Okuzu ◽  
Shunsuke Fujibayashi ◽  
Seiji Yamaguchi ◽  
Kazutaka Masamoto ◽  
Bungo Otsuki ◽  
...  

Peri-prosthetic infection and loosening of implants are major problems in orthopaedic and dental surgery. To address these issues, surface treatment methods for titanium implants have been improved by modifying the alkali and heat treatment. We have previously fabricated calcium-treated Ti metal that releases Sr ions (CaSr-Ti), which resulted in a higher in vitro osteogenic response and early in vivo bone bonding. Further, we developed a Ti metal that released both Sr and Ag ions (CaSrAg-Ti). In this study, we evaluated the antibacterial ability and osteogenic cellular response of CaSrAg-Ti and CaSr-Ti in vitro using rat bone marrow stromal cells (BMSCs) cultured on implant samples and extract mediums (EMs) made by immersing the implant samples in the medium. CaSrAg-Ti did not show cytotoxicity and was associated with a slightly higher osteogenic response when compared to CaSr-Ti, without inhibiting the effect of Sr. The osteogenic response was also observed in the cells cultured with the CaSrAg-Ti EM; however, the response was not as high as that of the cells on the CaSrAg-Ti implant sample. Significantly higher antibacterial activity was observed along with an antibacterial efficacy of more than 95% against methicillin-susceptible Staphylococcus aureus and Escherichia coli. The main advantages of our surface treatment are its simplicity and low cost. Therefore, our treatment is promising for clinical applications in orthopaedic or dental Ti-based implants with antibacterial and early bone-bonding abilities.


Author(s):  
S. NAVEENTAJ ◽  
Y. INDIRA MUZIB

Cubosomes are novel biocompatible drug delivery system and have honeycombed (cavernous) structures whose diameter size range from 10–500 nm. They appear like dots, which are likely to be spherical structures. Each dot corresponds to the presence of a pore containing aqueous cubic phase in the lipid water system. Cubosomes posse’s great significance in the field of cosmeceuticals and Pharmaceuticals due to its unique features and become an attractive choice of vehicle for in vivo drug delivery due to their low cost, safety, efficacy and versatility for controlled release application and functionalization. Cubosomes have a very simple method of preparation; biodegradability of selected lipids has the capability to encapsulate hydrophobic and hydrophilic substances. Cubosomes are considered to be versatile systems, and prepared cubosomes can be administrated by different ways such as oral, percutaneous and parenteral routes. On the whole, cubosomes offer high consequence in nano-based drug preparations for melanoma (skin cancer) treatment, targeted drug delivery systems and comprise a wide range of applications in many areas and are characterized by various parameters. Consequently, cubosomes are in progress forward of awareness in the Pharmaceutical division. This review article mainly focuses on the methods of preparation, advantages, and applications of cubosomes.


2019 ◽  
Author(s):  
Gabriele Selvaggio ◽  
Helen Preiß ◽  
Alexey Chizhik ◽  
Robert Nißler ◽  
Florian A. Mann ◽  
...  

ABSTRACTImaging of complex (biological) samples in the near infrared (nIR) range of the spectrum is beneficial due to reduced light scattering, absorption, phototoxicity and autofluorescence. However, there are only few near infrared fluorescent materials known and suitable for biomedical applications. Here, we exfoliate the layered pigment CaCuSi4O10 (known as Egyptian Blue, EB) via facile tip sonication into nanosheets (EB-NS) with ultra-high nIR fluorescence stability and brightness. The size of EB-NS can be tailored by tip sonication to diameters < 20 nm and heights down to 1 nm. EB-NS fluoresce at 910 nm and the total fluorescence intensity scales with the number of Cu2+ ions that serve as luminescent centers. Furthermore, EB-NS display no bleaching and ultra-high brightness compared to other nIR fluorophores. The versatility of EB-NS is demonstrated by in vivo single-particle tracking and microrheology measurements in developing Drosophila embryos. Additionally, we show that EB-NS can be uptaken by plants and remotely detected in a low cost stand-off detection setup despite strong plant background fluorescence. In summary, EB-NS are a highly versatile, bright, photostable and biocompatible nIR fluorescent material that has the potential for a wide range of bioimaging applications both in animal and plant systems.


Author(s):  
R.J. Mount ◽  
R.V. Harrison

The sensory end organ of the ear, the organ of Corti, rests on a thin basilar membrane which lies between the bone of the central modiolus and the bony wall of the cochlea. In vivo, the organ of Corti is protected by the bony wall which totally surrounds it. In order to examine the sensory epithelium by scanning electron microscopy it is necessary to dissect away the protective bone and expose the region of interest (Fig. 1). This leaves the fragile organ of Corti susceptible to physical damage during subsequent handling. In our laboratory cochlear specimens, after dissection, are routinely prepared by the O-T- O-T-O technique, critical point dried and then lightly sputter coated with gold. This processing involves considerable specimen handling including several hours on a rotator during which the organ of Corti is at risk of being physically damaged. The following procedure uses low cost, readily available materials to hold the specimen during processing ,preventing physical damage while allowing an unhindered exchange of fluids.Following fixation, the cochlea is dehydrated to 70% ethanol then dissected under ethanol to prevent air drying. The holder is prepared by punching a hole in the flexible snap cap of a Wheaton vial with a paper hole punch. A small amount of two component epoxy putty is well mixed then pushed through the hole in the cap. The putty on the inner cap is formed into a “cup” to hold the specimen (Fig. 2), the putty on the outside is smoothed into a “button” to give good attachment even when the cap is flexed during handling (Fig. 3). The cap is submerged in the 70% ethanol, the bone at the base of the cochlea is seated into the cup and the sides of the cup squeezed with forceps to grip it (Fig.4). Several types of epoxy putty have been tried, most are either soluble in ethanol to some degree or do not set in ethanol. The only putty we find successful is “DUROtm MASTERMENDtm Epoxy Extra Strength Ribbon” (Loctite Corp., Cleveland, Ohio), this is a blue and yellow ribbon which is kneaded to form a green putty, it is available at many hardware stores.


1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.


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