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Showing 5 results for Fiber
Effect of anti-microbial fiber and its interaction with gentamicin on Pseudomonas aeruginosa
Qaziasgar L, Kermanshahi Rk,
Volume 66, Issue 10 (1-2009)
Abstract

Background: Because of importance and extensive use of textile in clinical setting especially as bandage, so outbreak of nosocomial infections due to Bacteria resistance nanobiotechnological advances in recent decade, achieved methods for fabrication antimicrobial effect in fibers that can satisfied the needs of patients in the wake of health and hygiene.

Methods: The antimicrobial effect of special type of fibers produced in Isfahan Poly Acryl Plant on one resistant strain of Pseudomonas aeruginosa isolated from 54 wound samples of patients in Isabn e Maryam hospital and P.aeruginosa (PTCC1024) was studied by using shake flask method. In order to compare the effect of pure antimicrobial agent of the fiber with that of gentamicin, the minimal inhibitory concentration of these agents was tested on strains. The effect of the interaction of these two antimicrobial agents and their fractional inhibitory concentration on chosen strains was studied using checkerboard method.

Results: The results show inefficient effect by antimicrobial fiber on P.aeruginosa strains after 24 hrs. But despite the high level MIC of gentamicin on these bacteria (1-3 µg/ml), the MIC of pure antimicrobial agent of fiber at a level of 10-3 µl/ml caused growth inhibition. The interaction of these antibacterial agents on the P.aeruginosa isolated from wound was evaluated as synergism.

Conclusions: According to this study the antimicrobial effect of the fiber on growth inhibition of P.aeruginosa strains is negative (despite of significant effect by pure antimicrobial agent used in produced the antimicrobial fiber on examined strains).


Double-lumen endotracheal tube positioning: Bag compliance Vs. fiberoptic bronchoscopy
Noyan Ashraf Ma, Hoseini Mr, Bannazadeh M,
Volume 70, Issue 8 (11-2012)
Abstract

Background: Lung separation is the basis of thoracic anesthesia, which is performed by different instruments. Checking probable malpositioning of tracheal tube needs fiberoptic bronchoscopy. The aim of this study was to compare respirator suggested compliance with fiberoptic findings in detecting major tracheal tube malpositioning.
Methods: A total of 256 patients undergoing thoracic surgery with double-lumen tracheal tube insertion in Imam Khomeini Hospital, Tehran, Iran, during 2010-11 were divided into three groups (n=86). We used left-sided double-lumen tube (DLT) for left or right-sided surgeries (groups 1 and 2), and right-sided DLT for left-sided surgeries (group 3). The position of the tubes was evaluated and compared using bag compliance versus fiberoptic bronchoscopy.
Results: The mean age of the study population was 44.7±13.4 (16-73) years, while 155 (59.9%) were male. The sensitivity, specificity, positive and negative predictive values, and the accuracy of bag compliance test for left-sided DLT in supine position were 40% (95% CI: 20-60%), 99% (95% CI: 96-99%), 84% (95% CI: 54-94%) 92% (95% CI: 88-95%) and 92% (95% CI: 87-95%), respectively. The above-mentioned variables for lateral decubitus position respectively were 27%, 98%, 76%, 89%, and 88%. Malpositioning was more prevalent in right-sided DLTs (P=0.02).
Conclusion: Based on the results of this study, and the high specificity, positive predictive value, and accuracy of bag compliance test, its use is encouraged as an alternative to fiberoptic bronchoscopy for checking DLT position, specially, in emergent surgeries or when fiberoptic bronchoscopy is unreachable due to lack of expertise or personnel.


Expansion of umbilical cord blood hematopoietic stem cell on biocompatible nanofiber scaffolds: brief report
Fatemeh Eskandari , Masoud Soleimani , Nasim Kalantari , Mehdi Azad , Amir Allahverdi ,
Volume 72, Issue 11 (2-2015)
Abstract
Background: Hematopoietic stem cell transplantation (HSCT) is a therapeutic approach in treatment of hematologic malignancies and incompatibility of bone marrow. Umbilical cord blood (UCB) known as an alternative for hematopoietic stem/ progenitor cells (HPSC) for in allogenic transplantation. The main hindrance in application of HPSC derived from umbilical cord blood is the low volume of collected samples. So, ex vivo expansion of HPSCs is the useful approach to overcome this restriction. Synthetic biomaterials such as nanofibers is used to produce synthetic niches. The aim of this study was the ex vivo expansion of hematopoietic stem cells on biocompatible nanofiber scaffolds. Methods: This study was done at Tarbiat Modares University from November 2012 to June 2013 and was a research study. Umbilical cord blood CD133+ hematopoietic stem cells were separated using MidiMacs (positive selection) system by means of monocolonal antibody (microbeads) CD133. Flow cytometry was used to assess the purity of cells. Cell culture was done on plate (2 Dimensional) and fibronectin conjougated polyether sulfone nanofiber scaffold (3 Dimensional). Colony assay test was used to asses the ability of colonization of cells. Results: Cell count analysis revealed the expansion of hematopoietic stem cells in cell culture plate (2D environment) and on nanofiber scaffold (3D environment) after 2 weeks. Expansion of cells in 2D environment was greater than 3D condition. Colony assay test revealed that the colonization ability of cells decreased after 2 weeks, but this decrease was lower in scaffold culture than plate culture. Conclusion: This study demonstrated that umbilical cord blood CD133+ hematopoietic stem cells can expand on fibronectin conjugated polyether sulfone scaffold and we can use this system for expanding of cells in vitro situation.
Nanofiber poly ether sulfone as adipose derived stem cell holding scaffold with or without growth factor on wound healing in rat
Mohammd Javad Fatemi , Shirin Chehroudi , Tooran Bagheri , Sahar Saleh , Amir Atashi , Mohsen Saberi , Seyed Aboozar Hoseini , Shirin Araghi ,
Volume 74, Issue 12 (3-2017)
Abstract

Background: Acute and chronic wound healing has always been problematic. Stem cells with or without the scaffold carrying these cells have been proposed as new methods in the treatment of wounds. In this case study we have tried to examine the effect of scaffold made of polyether sulfone (PES) alone, with stem cells and along with stem cell and growth factor on wound healing in rats.

Methods: This experimental study was conducted in Animal Laboratory of Hazrat Fatemeh Hospital in 2012. In this study, 48 rats were randomly divided into four groups. A wound created on the back of each rat at the size of 3×3 cm. The surface of the wound in the first group is covered with PES seeded with adipose-derived stem cell (ASC) and growth factor (GF), in the second group with polyether Sulfone seeded with ASC, in the third group only with PEWS, and in the fourth group (control) with Vaseline gauze. On 20th and 35th days, the surface of the wound was assessed by photography in order to understand the process of healing. In addition, on days 20 and 45, the histopathology characteristics of the samples were studied with a biopsy of the wounds.

Results: The Results of wound healing in the control group was better than the other groups and its statistical difference between others was meaningful. (P=0.008, P=0.013, P=0.001) On day 20, by examining histopathological characteristics including epithelialization, the number of inflammatory cells, the amount of angiogenesis and collagen synthesis in control group, we gained better results. (P=0.000), But on day 45, the results in different parameters were not equal.

Conclusion: polyether sulfone scaffold alone or with adipose-derived stem cells couldn’t improve the process of wound healing. Also adding vascular endothelial growth factor (VEGF) did not change the results significantly.

Considerations of in-vivo breast tissue assessment using raman spectroscopy: a review article
Sadaf Alipour, Zohreh Dehghani-Bidgoli ,
Volume 81, Issue 6 (9-2023)
Abstract
Raman spectroscopy, as an emerging and promising molecular assessment tool, has attracted the attention of researchers, especially for disease diagnosis in human organs such as the breast. Although most of the Raman studies on the breast have dealt with ex-vivo examination of either intact or processed excised tissue specimens, there are some in-vivo studies, including intraoperative tumor margin assessment and a few non-invasive studies. Since the non-invasive or minimally invasive Raman assessment technique is an essential need for translation to clinical approaches, in the present article, the most recent and relevant studies in this regard have been reviewed to find and introduce the most proper Raman spectroscopy system’s specifications for in-vivo assessment of breast tissue.
Scholarly documents, including articles, books, and dissertations related to Raman assessment of breast tissue or in-vivo Raman assessment of other human organs, were perused in search of the most relevant technical details of Raman systems employed so far. On the one hand, the present study has covered Raman instrumentation aspects of diverse types of Raman spectroscopy, different types of laser source and their specifications, optical elements used in the delivery and collection of light to and from the tissue such as lenses and fibers, detectors and even calibration settings. On the other hand, the main Raman features corresponding to different breast pathologies have been studied, speculating their variations in a non-invasive setting. Having studied all, we tried to find the best feasible configuration for a Raman system in terms of the ability to meet the needs of a non-invasive, in vivo clinical examination of the breast. 
In terms of the Raman spectroscopy modality and laser source, SORS/TRS and 785nm laser diode, were selected for in vivo examination of the breast respectively. The pertinent parameters of the spectrograph, detector, and fiber optic probe were introduced as well.
In the present study, detailed specifications of a non-invasive, in vivo Raman apparatus for examination of breast tissue have been studied and specified.

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