An Actuated Variable-View Rigid Scope System to Assist Visualization in Diagnostic Procedures.

OBJECTIVE: Variable-view rigid scopes offer advantages compared to traditional angled laparoscopes for examining a diagnostic site. However, altering the scope's view requires a high level of dexterity and understanding of spatial orientation. This requires an intuitive mechanism to allow an operator to easily understand the anatomical surroundings and smoothly adjust the scope's focus during diagnosis. To address this challenge, the objective of this work is to develop a mechanized arm that assists in visualization using variable-view rigid scopes during diagnostic procedures. METHODS: A system with a mechanized arm to maneuver a variable-view rigid scope (EndoCAMeleon - Karl Storz) was developed. A user study was conducted to assess the ability of the proposed mechanized arm for diagnosis in a preclinical navigation task and a simulated cystoscopy procedure. RESULTS: The mechanized arm performed significantly better than direct maneuvering of the rigid scope. In the preclinical navigation task, it reduced the percentage of time the scope's focus shifted outside a predefined track. Similarly, for simulated cystoscopy procedure, it reduced the duration and the perceived workload. CONCLUSION: The proposed mechanized arm enhances the operator's ability to accurately maneuver a variable-view rigid scope and reduces the effort in performing diagnostic procedures.Clinical and Translational Impact Statement: The preclinical research introduces a mechanized arm to intuitively maneuver a variable-view rigid scope during diagnostic procedures, while minimizing the mental and physical workload to the operator.

A generic scope actuation system for flexible endoscopes.

BACKGROUND: A scope actuation system assists a surgeon in steering a scope for navigating an operative field during an interventional or diagnostic procedure. Each system is tailored for a specific surgical procedure. The development of a generic scope actuation system could assist various laparoscopic and endoscopic procedures. This has the potential to reduce the deployment and maintenance costs for a hospital, making it more accessible for clinical usage. METHODS: A modular actuation system (for maneuvering rigid laparoscopes) was adapted to enable incorporation of flexible endoscopes. The design simplifies the installation and disassembly processes. User studies were conducted to assess the ability of the system to focus onto a diagnostic area, and to navigate during a simulated esophagogastroduodenoscopy procedure. During the studies, the endoscope was maneuvered with (robotic mode) and without (manual mode) the actuation system to navigate the endoscope's focus on a predefined track. RESULTS: Results show that the robotic mode performed better than the manual mode on all the measured performance parameters including (a) the total duration to traverse a track, (b) the percentage of time spent outside a track while traversing, and (c) the number of times the scope focus shifts outside the track. Additionally, robotic mode also reduced the perceived workload based on the NASA-TLX scale. CONCLUSIONS: The proposed scope actuation system enhances the maneuverability of flexible endoscopes. It also lays the groundwork for future development of modular and generic scope assistant systems that can be used in both laparoscopic and endoscopic procedures.

Hybrid electrospun polyhydroxybutyrate/gelatin/laminin/polyaniline scaffold for nerve tissue engineering application: Preparation, characterization, and in vitro assay.

Despite the widespread central nervous system injuries, treatment of these disorders is still an issue of concern due to the complexities. Natural recovery in these patients is rarely observed, which calls for developing new methods that address these problems. In this study, natural polymers of polyhydroxybutyrate (PHB) and gelatin were electrospun into scaffolds and cross-linked. In order to modify the PHB-based scaffold for nerve tissue engineering, the scaffold surface was modified by exposure to the ammonium gas plasma under controlled conditions, and the laminin as a promoter for neural cells was coated on the sample surface. Then, polyaniline nanoparticles were inkjet-printed on a sample surface as parallel lines to induce the differentiation of stem cells into neural cells. Infrared spectroscopy, absorption of PBS, AFM, degradation rate, contact angle, electron microscopy and optical microscopy, thermal and mechanical behavior, and analysis of the viability of L929 cells were investigated for the scaffolds. The results showed gelatin decreased the contact angle from 106.2° to 38° and increased the residual weight after PBS incubation from 82 % to 38 %. The moduli of the scaffold increased from 8.78 MPa for pure PHB to 28.74 for the modified scaffold. In addition, performed methods increased cell viability from 69 % for PHB to 89 % for modified scaffold and also had a favorable effect on cell adhesion. Investigation of culturing P19 stem cells demonstrated that they successfully differentiated into neural cells. Results show that the scaffolds prepared in this study were promising for nerve tissue engineering.

Scope actuation system for articulated laparoscopes.

BACKGROUND: An articulated laparoscope comprises a rigid shaft with an articulated distal end to change the viewing direction. The articulation provides improved navigation of the operating field in confined spaces. Furthermore, incorporation of an actuation system tends to enhance the control of an articulated laparoscope. METHODS: A preliminary prototype of a scope actuation system to maneuver an off-the-shelf articulated laparoscope (EndoCAMaleon by Karl Storz, Germany) was developed. A user study was conducted to evaluate this prototype for the surgical paradigm of video-assisted thoracic surgery. In the study, the subjects maneuvered an articulated scope under two modes of operation: (a) actuated mode where an operating surgeon maneuvers the scope using the developed prototype and (b) manual mode where a surgical assistant directly maneuvers the scope. The actuated mode was further assessed for multiple configurations based on the orientation of the articulated scope at the incision. RESULTS: The data show the actuated mode scored better than the manual mode on all the measured performance parameters including (a) total duration to visualize a marked region, (a) duration for which scope focus shifts outside a predefined visualization region, and (c) number of times for which scope focus shifts outside a predefined visualization region. Among the different configurations tested using the actuated mode, no significant difference was observed. CONCLUSIONS: The proposed articulated scope actuation system facilitates better navigation of an operative field as compared to a human assistant. Secondly, irrespective of the orientation in which an articulated scope's shaft is inserted through an incision, the proposed actuation system can navigate and visualize the operative field.

Fabrication of electrospun nanofibrous thermoresponsive semi-interpenetrating poly(N-isopropylacrylamide)/polyvinyl alcohol networks containing ZnO nanoparticle mats: characterization and antibacterial and cytocompatibility evaluation.

Thermoresponsive nanofiber composites comprising biopolymers and ZnO nanoparticles with controlled release and antibacterial activity are fascinating scientific research areas. Herein, poly(N-isopropylacrylamide) (PNIPAm) was prepared and mixed with poly(vinyl alcohol) (PVA) in 75/25 and 50/50 weight ratios together with ZnO (0, 1, and 2 phr) to construct nanofiber composites. The morphology of the crosslinked nanofiber composites, ZnO content, and their mechanical behavior were assessed by SEM, EDX, and tensile analyses. The wettability results show an increment in nanofiber surface hydrophobicity by increasing the temperature above the LCST of PNIPAm. The in vitro ZnO release exhibits a faster release profile for the sample with 50 wt% PNIPAm (lower crosslinking density) compared to the one with 25 wt%. Besides, a strong interaction between PVA hydroxyl groups and ZnO can restrict the release content. However, by increasing the temperature from 28 to 32 °C, the relative ZnO release becomes half for both compositions. All crosslinked nanofiber composites demonstrated reliable biocompatibility against L929 fibroblast cells. Agar disc-diffusion and optical density methods showed thermo-controllable antibacterial activity against Staphylococcus aureus upon temperature variation between 28 and 32 °C. Furthermore, in vivo and histological results indicate the potentiality of the prepared multidisciplinary wound dressing for robust wound healing and skin tissue engineering.

Preliminary design and evaluation of a generic surgical scope adapter.

BACKGROUND: Robotic scope assistant systems are used to visualise and navigate the operative field during a laparoscopic surgery. The objective of this work is to design a surgical scope adapter that enables control of different scope types (zero-degree, angulated, and articulated), and can be connected to any six degree-of-freedom robotic manipulator for usage as a robotic scope assistant system. METHODS: A surgical scope adapter compatible with different camera heads and scope types was designed and prototyped. The technical performance of the scope adapter was evaluated and a user study was conducted to assess the human-in-the-loop control. RESULTS: All the subjects were able to navigate the simulated operative field. The scope adapter permits continuous motion to explore the operative field as well as intermittent motion to accurately focus on the targeted anatomical landmarks. CONCLUSION: The modular and generic nature of the surgical scope adapter may enable its usage across different minimally invasive surgeries.

Highly porous bio-glass scaffolds fabricated by polyurethane template method with hydrothermal treatment for tissue engineering uses.

Objectives: Bioglass scaffolds, which contain a significant percentage of porosity for tissue engineering purposes, have low strength. For increasing the strength and efficiency of such structures for use in tissue engineering, fabrication of hierarchical meso/macro-porous bioglass scaffolds, developing their mechanical strength by hydrothermal treatment and adjusting pH method, and achieving the appropriate mesopore size for loading large biomolecules, were considered in this study. Materials and Methods: Mesoporous bioglass (MBG) powders were synthesized using cetyltrimethylammonium bromide as a surfactant, with different amounts of calcium sources to obtain the appropriate size of the mesoporous scaffolds. Then MBG scaffolds were fabricated by a polyurethane foam templating method, and for increasing scaffold strength hydrothermal treatment (90 °C, for 5 days) and adjustment pH (pH=9) method was used to obtain hierarchical meso/macro-porous structures. The sample characterization was done by Simultaneous thermal analysis, Fourier transform infrared spectroscopy, Field Emission Scanning electron microscopy, small and wide-angle X-ray powder diffractions, transmission electron microscopy, and analysis of nitrogen adsorption-desorption isotherm. The mechanical strength of scaffolds was also determined. Results: The MBG scaffolds based on 80.28 (wt.) % SiO2- 17.89 (wt.) % CaO- 1.81 (wt.) % P2O5 presented interconnected large pores and pores in the range of 100-150 µm and 6-18 nm, respectively and 0.4 MPa compressive strength. Conclusion: The total pore volume and specific surface area were obtained from the Brunauer-Emmett-Teller theory, 0.709 cm3 g-1 and 213.83 m2 g-1, respectively. These findings could be considered in bone-cartilage tissue engineering.

In vitro and in vivo evaluation of nanofibre mats containing Calendula officinalis extract as a wound dressing.

OBJECTIVE: The present study aims to create Calendula officinalis-loaded nanofibre-based wound dressing materials to enhance the wound healing process. Calendula officinalis is an annual herb native to the Mediterranean region. It is antipyretic, antifungal, antioedema, antidiabetic, anti-inflammatory (wound, oral and pharyngeal mucosa), antispasmodic, treats chronic ocular surface diseases, acts as a stimulant and a diaphoretic. It is also used in the prevention of acute dermatitis, and in the treatment of gastrointestinal ulcers, wounds and burns. METHOD: Electrospinning is an effective method for creating nano- and microfibres for biomedical applications. Calendula officinalis (CA) of various concentrations 5%, 10% and 15%)-loaded polyvinyl alcohol (PVA)/sodium alginate (SAlg) nanofibre mats were successfully produced via blend electrospinning. Nanofibre mats were evaluated using: scanning electron microscopy (SEM); Fourier transform infrared spectroscopy (FTIR) analysis; gel content; water vapour transmission rate (WVTR); swelling ratio; in vitro drug release studies; viability evaluation (cell culture and MTT assay); and an in vivo study using male Wistar rats. Rats were divided into three groups (n=3). In each group, rats were inflicted with five full-thickness wounds on the back and were treated with sterile gauze (control), PVA/SAlg nanofibre dressing (CA-free control), PVA/SAlg/CA5%, PVA/SAlg/CA10%, and PVA/SAlg/CA15% nanofibre dressing. RESULTS: Results showed that the obtained fibres were smooth with no surface aggregates, indicating complete incorporation of Calendula officinalis. The release of Calendula officinalis from loaded PVA/SAlg fibre mats in the first four hours was burst released and then was constant. PVA/SAlg and PVA/SAlg/CA nanofibres were not toxic to L929 mouse fibroblasts and supported cell attachment and proliferation. The results of the in vivo study showed that the PVA/SAlg/CA10% nanofibre dressing had a higher full-thickness wound healing closure rate compared with the control group on days seven, 14 and 21 after treatment. CONCLUSION: The results of this evaluation showed that PVA/SAlg/CA nanofibrous mats could be a candidate as an effective wound dressing; however, the percentage of CA in this compound needs further investigation.

Comparative Evaluation of a Commercial Herbal Extract and 0.2% Chlorhexidine Mouthwash on Three Periodontal Facultative Anaerobes: An In Vitro Study.

Background: The application of herbal and/or chemical antimicrobial mouthwashes in addition to the mechanical methods of bacteria removal helps reduce the periopathogens and thus increase the periodontal tissues' health. The present study aimed to evaluate the antibacterial effect of Thymex (TMX) syrup on three periodontal facultative anaerobes in vitro and compare it with 0.2% chlorhexidine (CHX) mouthwash. Methods: In this in vitro experiment, the disc diffusion method was used to measure the inhibitory halo diameter (IhD) of Enterobacter cloacae, Actinomyces viscosus, and Eikenella corrodens. The paper discs containing TMX and CHX were placed on Mueller-Hinton agar media and cultured with the mentioned bacteria. Moreover, a blank disc containing distilled water was used as a control. From each of the three bacterial species, five samples were taken, and after 18 hours of storage in the incubator, the IhDs were measured in millimeters. A one-way ANOVA test and an independent sample t-test were used to compare the mean differences of IhDs between groups. The significance level was considered to be 0.05. Results: The IhDs ranged between 6.2-8.8 mm and 12.3-34 mm for TMX and CHX, respectively. CHX showed a more inhibitory effect on all three species of bacteria compared to TMX mouthwash (P < 0.001). Conclusions: Despite the inhibitory effect of TMX on bacterial growth, CHX showed significantly more antibacterial activity than TMX against three studied bacterial species.

Platelet-rich plasma-hyaluronic acid/chondrotin sulfate/carboxymethyl chitosan hydrogel for cartilage regeneration.

In this study, the chondrogenic potential of hyaluronic acid/chondrotin sulfate/carboxymethyl chitosan hydrogels with adipose-derived mesenchymal stem cells (ADMSCs) was evaluated. Here, hyaluronic acid, chondrotin sulfate, and carboxymethyl chitosan were used as the substrate for cartilage tissue engineering in which the hydrogel is formed due to electrostatic and hydrogen bonds through mixing the polymers. Because of the instability of this hydrogel in the biological environment, 1-ethyl-3-(3-dimethylaminopropyl-carbodiimide hydrochloride/N-hydroxy-succinimide was used as a crosslinker to increase the hydrogel stability. The hydrogels showed reasonable stability due to the combined effect of self-crosslinking and chemical crosslinking. The cells were treated with the prepared hydrogel samples for 14 and 21 days in nondifferentiation medium for evaluation of the cellular behavior of ADMSCs. Gene expression evaluation was performed, and expression of specific genes involved in differentiation was shown in the crosslinked hydrogel with platelet-rich plasma (PRP) (H-EN-P) had increased the gene expression levels. Quantification of immunofluorescence intensity indicated the high level of expression of SOX9 in H-EN-P hydrogel. Based on the results, we confirmed that the presence of PRP and the similarity of the hydrogel constituents to the cartilage extracellular matrix could have positive effects on the differentiation of the cells, which is favorable for cartilage tissue engineering approaches.

Thermomechanical Buckling Analysis of the E&P-FGM Beams Integrated by Nanocomposite Supports Immersed in a Hygrothermal Environment.

Due to the widespread use of sandwich structures in many industries and the importance of understanding their mechanical behavior, this paper studies the thermomechanical buckling behavior of sandwich beams with a functionally graded material (FGM) middle layer and two composite external layers. Both composite skins are made of Poly(methyl methacrylate) (PMMA) reinforced by carbon-nano-tubes (CNTs). The properties of the FGM core are predicted through an exponential-law and power-law theory (E&P), whereas an Eshelby-Mori-Tanaka (EMT) formulation is applied to capture the mechanical properties of the external layers. Moreover, different high-order displacement fields are combined with a virtual displacement approach to derive the governing equations of the problem, here solved analytically based on a Navier-type approximation. A parametric study is performed to check for the impact of different core materials and CNT concentrations inside the PMMA on the overall response of beams resting on a Pasternak substrate and subjected to a hygrothermal loading. This means that the sensitivity analysis accounts for different displacement fields, hygrothermal environments, and FGM theories, as a novel aspect of the present work. Our results could be replicated in a computational sense, and could be useful for design purposes in aerospace industries to increase the tolerance of target productions, such as aircraft bodies.

Clinical predictors of I-131 therapy failure in differentiated thyroid cancer by machine learning: A single-center experience.

Well-differentiated thyroid carcinoma is predominantly a slow-growing malignancy, amendable to treatment, and has an excellent prognosis following thyroidectomy and radioiodine (RAI) therapy. However, patients who fail the initial RAI treatment attempt may require repeated RAI or other treatments and with this, comes an associated impact on patient quality of life. Therefore, the anticipation of patients in whom there is a higher risk of RAI failure may help in patient risk stratification and subsequent management. We conducted a retrospective review to determine the factors associated with initial RAI therapy failure in well-differentiated thyroid cancer patients. Using scikit-learn from Python, we implemented a machine-learning algorithm to determine the clinical patient factors associated with a higher likelihood of treatment resistance. We found that clinical factors such as tumor focality (P = 0.026) and lymph node invasion at surgical resection (P = 0.0135) were significantly associated with initial treatment failure following RAI. Elevated serum thyroglobulin (Tg) and Tg antibody levels following surgery but before RAI were also associated with treatment resistance (P < 0.0001 and P = 0.011 respectively). Less expected factors such as decreased time from surgery to RAI were also associated with treatment failure, however not to a statistically significant degree (P > 0.064). Clinical outcomes following RAI can be stratified by identifying factors that are associated with initial treatment failure. These findings can help restratify patients for RAI treatment and change patient management in certain cases. Such stratification will ultimately help to optimize successful treatment outcomes and improve patient quality of life.

Fabrication of carboxymethyl chitosan/poly(ε-caprolactone)/doxorubicin/nickel ferrite core-shell fibers for controlled release of doxorubicin against breast cancer.

The coaxial electrospinning for producing core-shell nanofibers due to control the release profile of drug by the shell layer has been developed. N-carboxymethyl chitosan (CMC)-polyvinyl alcohol (core)/poly(ε-caprolactone) (PCL) (shell) nanofibers were produced via coaxial electrospinning. Doxorubicin (DOX) and nickel ferrite nanoparticles were incorporated into the nanofibers for controlled release of DOX against MCF-7 breast cancer. The minimum CMC/PCL fiber diameter was found to be 300 nm by optimizing of three variables including voltage to distance ratio (1.5-2.5 kV/cm), CMC concentration (4-6 wt.%) and PCL concentration (8-12 wt.%). The synthesized core-shell fibers were characterized using FTIR, XRD, SEM, and TEM analysis. The extended release and controlled release of DOX from core-shell nanofibers were achieved under physiological pH without external magnetic field (EMF) and acidic pH with EMF during 25 and 7 days, respectively. The maximum cytotoxicity of MCF-7 breast cancer cells was about 83 % using CMC/PCL/nickel ferrite 10 % nanofibers and EMF.

Enhanced antimicrobial and full-thickness wound healing efficiency of hydrogels loaded with heparinized ZnO nanoparticles: In vitro and in vivo evaluation.

Nanotechnology-based fabricated wound dressings are known as appropriate substrates to enhance healing in both acute and chronic wounds. These types of materials have the ability to deliver therapeutic agents. In this study, a wound dressing including heparinized zinc oxide nanoparticles in combination with chitosan and poly(vinyl alcohol) was developed to investigate its antibacterial and regenerative properties in a rat model of full thickness skin wounds. By adding nanoparticles, the mechanical strength increased up to twice as compared to the sample without nanoparticles. In addition, heparin release profile follows the Hixson-Crowell release kinetic. Protein adsorption enhanced by adding nanoparticles in hydrogels and the prepared wound dressings were completely biocompatible. In terms of antibacterial activity, the minimum inhibitory concentration decreased by conjugation of heparin on the surface of zinc oxide nanoparticles compared to the non-functionalized nanoparticles, and, this shows the increased antibacterial synergistic effect by adding heparin to nanoparticles. Furthermore, it was found that the heparinized zinc oxide nanoparticles effectively accelerate wound closure, re-epithelialization and decrease collagen deposition compared to other groups after implantation. Hence, the prepared wound dressings have the capacity to significantly enhance healing of acute wounds.

Poly(hydroxybutyrate-co-hydroxyvalerate) Porous Matrices from Thermally Induced Phase Separation.

Thermally induced phase separation followed by freeze drying has been used to prepare biodegradable and biocompatible scaffolds with interconnected 3D microporous structures from poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) copolymers containing 5 and 12 wt % of 3-hydroxyvalerate (HV). Solutions of PHBV in 1,4-dioxane, underwent phase separation by cooling under two different thermal gradients (at -25 °C and -5 °C). The cloud point and crystallization temperature of the polymer solutions were determined by turbidimetry and differential scanning calorimetry, respectively. Parameters affecting the phase separation mechanism such as variation of both the cooling process and the composition of the PHBV copolymer were investigated. Afterwards, the influence of these variables on the morphology of the porous structure and the final mechanical properties (i.e., rigidity and damping) was evaluated via scanning electron microscopy and dynamic mechanical thermal analysis, respectively. While the morphology of the scaffolds was considerably affected by polymer crystallization upon a slow cooling rate, the effect of solvent crystallization was more evident at either high hydroxyvalerate content (i.e., 12 wt % of HV) or high cooling rate. The decrease in the HV content gave rise to scaffolds with greater stiffness because of their higher degree of crystallinity, being also noticeable the greater consistency of the structure attained when the cooling rate was higher. Scaffolds were fully biocompatible supports for cell adhesion and proliferation in 3D cultures and show potential application as a tool for tissue regeneration.

Quasi-3D Hyperbolic Shear Deformation Theory for the Free Vibration Study of Honeycomb Microplates with Graphene Nanoplatelets-Reinforced Epoxy Skins.

A novel quasi-3D hyperbolic shear deformation theory (QHSDT) with five unknowns is here employed, together with the Hamilton's principle and the modified couple stress theory (MCST) to analyze the vibrational behavior of rectangular micro-scale sandwich plates resting on a visco-Pasternak foundation. The sandwich structure features a Nomex or Glass phenolic honeycomb core, and two composite face sheets reinforced with graphene nanoplatelets (GPLs). The effective properties of both face sheets are evaluated by means of the Halpin-Tsai and extended rule of mixture (ERM) micromechanical schemes. The governing equations of the problem are derived by applying the Hamilton's principle, whose solutions are determined theoretically according to a classical Navier-type procedure. A parametric study checks for the effect of different material properties, length-scale parameters, foundation parameters and geometrical properties of the honeycomb cells, and the reinforcing GPLs, on the vibration response of the layered structure, which can be of great interest for many modern engineering applications and their optimization design.

Preparation and modeling of electrospun polyhydroxybutyrate/polyaniline composite scaffold modified by plasma and printed by an inkjet method and its cellular study.

The reconstruction of the nerve tissue engineering scaffold is always of particular interest due to the inability to recover and repair neural tissues after being damaged by diseases or physical injuries. The primary purpose of this study was obtaining a model used to predict the diameter of the fibers of electrospun polyhydroxybutyrate (PHB) scaffolds. Accordingly, the range of operating parameters, namely the applied voltage, the distance between the nozzle to the collector, and solution concentration, was designed for the electrospinning process at three different levels, giving seventeen experiments. These data were modeled utilizing response surface methodology and artificial neural network method using Design Expert and Matlab software.The effect of process parameters on the diameter, as well as their interactions were investigated in detail, and the corresponding models were suggested. Both the RSM and ANN models showed an excellent agreement between the experimental and predicted response values. In the second phase of the study, PHB natural polymer was electrospun into scaffolds with high biocompatibility, resulting in a 224-360 nm diameter range .To further modify the scaffold in order to improve the compatibility of PHB, the fibrous surface of scaffolds was exposed to oxygenated plasma gas radiation under controlled conditions. Next, polyaniline (PANI) nanoparticles were then synthesized and printed on the surface of scaffolds as parallel lines. Then samples were exposed to the electric field. Fourier-transform infrared spectroscopy, water contact angle, optical and electron microscopy, tensile test, and cell viability analysis were performed to study properties of resulting scaffolds. The results indicated the fact that modification of the scaffolds by oxygen plasma and printing PANI nanoparticles in particular patterns had a favorable impact on cell adhesion and direction of cell growth, showing the potential of resulting scaffolds for nerve tissue engineering applications.

Effects of different quantities of antibody conjugated with magnetic nanoparticles on cell separation efficiency.

Antibody-conjugated magnetic nanoparticles (Ab-MNPs) have received considerable attention in bioseparation and clinical diagnostics assays due to their unique ability to detect and isolate a variety of biomolecules and cells. Because antibodies can be expensive, a key challenge for bioconjugation is to determine the optimal amount of antibodies with reasonable antigen-capturing activity. We designed an approach to determine the minimum amounts of antibodies for efficient coating. Different quantities of Herceptin (anti-human epidermal growth factor receptor 2: HER2) antibody were applied and immobilized on the surface of MNPs. Antibody binding was then checked by using an anti-human antibody conjugated with fluorochrome and flow cytometry. When the ratio of MNPs to antibodies increased from 0.79 to 795.45, mean fluorescence intensity (MFI) of conjugated MNPs decreased markedly from 185.56 to 20.07, indicating lower surface antibody coverage. We then investigated the relation between antibody content and isolation efficiency. Three Ab-MNP samples with different MFI were used to isolate SK-BR-3, a HER2-positive breast cancer cell line, from mixtures of whole blood or mononuclear cells. After isolation in a magnetic field, separation efficiency was evaluated by fluorescence microscopy and flow cytometry-based techniques. Our results collectively showed that the amount of anti-HER2 antibodies for conjugation with MNPs could be decreased by as much as one-fifteenth without compromising isolation efficiency, which in turn can reduce the cost of immunoassay biosensors.

Association between physical activity, cardiorespiratory fitness, and body composition with menopausal symptoms in early postmenopausal women.

OBJECTIVE: The aim of this study was to investigate the relationship between daily physical activity (daily activities, exercise, and sitting time), cardiorespiratory fitness (CRF), and body composition (body mass index [BMI], waist to hip ratio [WHR)] with menopausal symptoms and to determine the strongest predictor(s) of menopausal symptoms. METHODS: The Menopause Rating Scale questionnaire was used to examine somatic, psychological, urogenital, and total symptoms of menopause. The energy expenditure of daily physical activity, exercise, and sitting time was measured by the International Physical Activity Questionnaire, and CRF was measured by estimating the maximal oxygen intake (VO2max) through the Rockport test. Statistical methods of the Pearson correlation coefficient and hierarchical multiple linear regression were used for data analysis. RESULTS: Fifty-six women, aged 50 to 65 years, voluntarily participated in the study. Exercise energy expenditure was inversely correlated with total (r = -0.403, P = 0.002), somatic (r = -0.293, P = 0.023), and urogenital (r = -0.343, P = 0.009) symptoms of menopause. VO2max was inversely correlated with urogenital symptoms of menopause (r = -0.414, P = 0.002). WHR was positively correlated with somatic symptoms of menopause (r = 0.286, P = 0.032); sitting was correlated with total (r = 0.40, P = 0.002), somatic (r = 0.325, P = 0.015), and psychological (r = 0.274, P = 0.015) symptoms of menopause. Among the study variables, sitting (ß=0.365, P = 0.004) and VO2max (ß=-0.286, P = 0.030) were the most important predictors of total symptoms of menopause; sitting was the predictor of somatic symptoms (ß=0.265, P = 0.045), and VO2max was the predictor of urogenital symptoms of menopause (ß=-0.332, P = 0.014). The inclusion of age, BMI, WHR, and duration of menopause as confounding variables in regression analysis did not change the findings related to the predictions of menopausal symptoms. CONCLUSION: Reducing sitting time, improving VO2max, decreasing WHR, and exercise can be recommended by priority to alleviate menopausal symptoms. Considering the small number of participants in this investigation, future studies are, however, recommended.

Bronchodilatory effects of B-type natriuretic peptide in acute asthma attacks: a randomized controlled clinical trial.

INTRODUCTION: B-type natriuretic peptide (BNP) regulates different physiological processes such as blood pressure, cardiac growth, and neural and skeletal development. Thus, the aim of this study w as to evaluate the effect of BNP in the treatment of acute asthma attacks. MATERIAL AND METHODS: In this randomized clinical trial, patients with acute asthma attacks were enrolled. The patients were divided randomly into two groups. Patients in the interventional group received BNP via intravenous infusion. Two µg/kg of BNP was injected as a bolus in 60 seconds. Then, infusion of BNP immediately began and was given in 0.01, 0.02, and 0.03 µg/kg/min doses every 30 minutes for the first 1.5 hours. The patients in the control group received nebulized salbutamol. Afterwards, peak flow meter findings, hemodynamic parameters, and estimation of the clinical severity of asthma in both groups were checked every 30 minutes. RESULTS: In total, 40 patients were included in this study. The values of PEFR in the 60th and 90th minutes in the control group were lower than those in the interventional group. In the 60th minute, the mean of PEFR was 377.3 in the BNP group but 335.95 in the control group (P = 0.049). Moreover, this difference remained significant in the 90th minute (P = 0.021). However, forced expiratory volume in one second (FEV1) did not differ between the groups at any time (p > 0.05). CONCLUSION: Although a large experimental study is needed to verify our hypothesis, it seems that BNP might be a therapeutic option in asthma exacerbations, particularly in those with b2 agonist receptor polymorphism.