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1.
Turk J Med Sci ; 53(3): 824-834, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37476895

ABSTRACT

BACKGROUND: To investigate the possible relationship between pectoralis muscle (PM) measurement and frailty in older women with breast cancer (BC) (preoperatively defined as stage 1, 2, and 3 diseases). METHODS: This retrospective, observational study was conducted at Konya Training and Research Hospital between June and December 2020. A total of 102 patients [median age 62.5 years, median follow-up period two years] were included in the study. PM measurements were obtained from thorax computerized tomography (CT). Pectoralis muscle index (PMI) was calculated by dividing the PM area by the height square of the patients (cm2/m2). Pectoralis muscle density (PMD) was evaluated using CT findings, including their Hounsfield Units (HU). Frailty status and sarcopenia-risk assessments were done by a telephone interview in September 2020 using the FRAIL index (categorized as robust or nonrobust) and SARC-F questionnaire (classified as no sarcopenia-risk or risk of sarcopenia), respectively. PM measurements were compared between robust and nonrobust patients and between patients with a risk of sarcopenia and no sarcopenia risk. RESULTS: The nonrobust patients had lower pectoralis major muscle index (PMaMI) (p = 0.041) and pectoralis major muscle density(PMaD) (p = 0.020) levels than robust patients in the whole study sample. PMI (p = 0.017) and PMaMI (p = 0.010) levels were significantly lower in the nonrobust patients than in robust patients with early-stage BC. Frailty status was positively correlated with age (rho: 0.621; p < 0.001), BC stage (rho: 0.220; p = 0.026), and SARC-F score (rho: 0.747; p < 0.001), and negatively correlated with PMaMI (rho: -0.197; p = 0.047) and PMaD (rho: -0.237; p = 0.016). There were significant associations between PMaMI (OR: 0.467, 95% Confidence Interval (CI): 0.226-0.962 p = 0.039) and PMI (OR: 0.543, 95% CI: 0.299-0.986 p = 0.045) levels with frailty status (being nonrobust) in regression models. DISCUSSION: In the study, it has been shown that pectoralis muscle assessment might be a related parameter to frailty in older women with breast cancer.


Subject(s)
Breast Neoplasms , Frailty , Sarcopenia , Humans , Female , Aged , Middle Aged , Frailty/epidemiology , Pectoralis Muscles/diagnostic imaging , Breast Neoplasms/complications , Breast Neoplasms/epidemiology , Frail Elderly , Retrospective Studies , Sarcopenia/epidemiology
2.
Turk Kardiyol Dern Ars ; 49(8): 606-614, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34881698

ABSTRACT

OBJECTIVE: To assess the effects of transvalvular aortic valve implantation (TAVI) on the outcomes of the patients with symptomatic severe aortic stenosis (AS), and predict the effect of left ventricular ejection fraction (LVEF) and cardiac structural recovery on mortality after the TAVI in patients with different stage of LV function. METHODS: Out of 191 patients, 151 consecutive patients in 3 centers were evaluated for outcome analysis. Patients were classified into 3 subgroups as AS with reduced ejection fraction (ASrEF) (LVEF <40%), AS with mildly reduced EF (ASmrEF) (LVEF 40-49%) and AS with preserved EF (ASpEF) (LVEF ≥50%). RESULTS: The mean follow-up period was 19.4±12.4 (up to 54) months. All-cause mortality was not different among all 3 groups. (p=0.901). In multivariate analysis, stroke volume index (SVI) (Exp(B): 0.039, 95% confidence interval [CI]: 0.011-0.013, p<0.001), baseline blood urea nitrogen (Exp(B): 1.022, 95% CI: 1.006-1.038, p=0.006), and percent LVEF change after TAVI (d-LVEF) (Exp(B): 0.046, 95% CI: 0.004-0.610, p=0.046) were the independent predictors for mortality after TAVI. The receiver operating characteristic curve analysis showed that the cutoff value of "≤10%" for d-LVEF had sensitivity of 50%, specificity of 75%, and an area under the curve of 0.72 in predicting mortality in patients with SVI <35 mL/m2. CONCLUSION: Improvement of LVEF after TAVI, which reflected the marked LV reverse remodeling, has an impact on the prediction of the survival in patients with AS, and this is more prominent in patients with low SVI.


Subject(s)
Aortic Valve Stenosis/mortality , Aortic Valve Stenosis/surgery , Stroke Volume/physiology , Transcatheter Aortic Valve Replacement/mortality , Ventricular Function, Left/physiology , Aged , Aortic Valve Stenosis/classification , Blood Urea Nitrogen , Cause of Death , Echocardiography , Female , Follow-Up Studies , Humans , Male , Multivariate Analysis , ROC Curve , Retrospective Studies , Sensitivity and Specificity , Transcatheter Aortic Valve Replacement/adverse effects , Treatment Outcome , Ventricular Dysfunction, Left/physiopathology
3.
Lab Chip ; 21(17): 3289-3297, 2021 09 07.
Article in English | MEDLINE | ID: mdl-34612459

ABSTRACT

Tacrolimus is one of the most effective and prevalent drugs used to combat vascularized composite allotransplantation rejection. We have fabricated a rapid and easy-to-use six-layer paper based microfluidic device using the principles of competitive immunoassays and vertical flow microfluidics for colorimetric detection of tacrolimus in a small volume of blood.


Subject(s)
Biosensing Techniques , Vascularized Composite Allotransplantation , Drug Monitoring , Graft Rejection , Tacrolimus
4.
Eur J Gastroenterol Hepatol ; 33(11): 1441-1450, 2021 11 01.
Article in English | MEDLINE | ID: mdl-33741802

ABSTRACT

BACKGROUND: Cirrhotic cardiomyopathy (CCM) is a well-known entity. The aim of this study was to compare left atrial three-dimensional (3D) volume and P-wave dispersion (PWd) in patients with cirrhosis and a healthy population. The secondary purpose was to assess the left phasic volumes and reservoir functions with 3D echocardiography for the prediction of an increased risk of poor outcomes in patients with cirrhosis. METHODS: The study included 50 patients with cirrhosis and 43 healthy control subjects without atrial fibrillation. All patients were assessed with two-dimensional (2D), 3D, and tissue Doppler transthoracic echocardiography. The PWd was calculated using a 12-lead surface electrocardiogram (ECG). Cirrhotic patients were followed up for 2.5 years for the evaluation of poor outcomes and the development of atrial fibrillation. RESULTS: Patients with cirrhosis were observed to have significantly higher left atrial phasic volumes such as minimal left atrial volume (3D-LAVmin, P = 0.004) and indexed LAVmin (3D-LAVImin, P = 0.0001), and significantly decreased left atrial reservoir functions such as left atrial emptying volume (3D-LAEV, P = 0,001), left atrial ejection fraction (3D-LAEF, P = 0,001) on 3D echocardiography. PWd was determined to be significantly longer in the cirrhotic group compared with the control group (P = 0.003). In the 2.5-year follow-up period, poor outcomes occurred in 34 patients (22 patients died, six patients had liver transplantation, six patients developed atrial fibrillation/AHRE episodes). In Cox regression analysis, the MELD score (HR, 1.16 (1.06-1.26), P = 0.001) and 3D-LAVImin (HR, 0.95 (0.86-1.00), P = 0.040) were significantly associated with all-cause mortality. Cirrhotic patients with LAVImin of >15 ml/m2 were seen to have poor survival (long rank P = 0.033). CONCLUSION: The results of this study showed that patients with cirrhosis had higher left atrial volume, longer PWd and worse diastolic functions compared with the control group. Higher disease severity scores were associated with left atrial function and volume. In addition, left atrial volume measured with 3DE was a strong predictor of future adverse events, and minimal left atrial volumes had a higher prognostic value than any other left atrial function indices.


Subject(s)
Atrial Function, Left , Echocardiography, Three-Dimensional , Heart Atria/diagnostic imaging , Humans , Liver Cirrhosis/complications , Liver Cirrhosis/diagnostic imaging , Prognosis
5.
Mil Med ; 186(Suppl 1): 716-721, 2021 01 25.
Article in English | MEDLINE | ID: mdl-33499548

ABSTRACT

INTRODUCTION: We developed low-cost, portable paper-based diagnostic devices for detection of human immunoglobulin M (IgM) and immunoglobulin G (IgG) in serum without any sample preparation. These devices can be used to help identify presence of diseases, used to provide rapid results (<5 minutes), readily used by untrained personnel, employed in austere environments, configured to obtain multiplexed assays, and easily disposed of. MATERIALS AND METHODS: We successfully accomplished colorimetric detection of human IgG and human IgM using a sandwich-style assay within the microfluidic paper device via vertical flow immunoassay configuration. The reaction zone in the wax printed paper layer is a small circular pattern. Gold nanoparticles conjugated with anti-human IgG and IgM antibodies have been used for colorimetric detection of IgG or IgM by naked eye. Colorimetric signal can be precisely quantified through implementation of image analysis software which can be developed as an app for a smartphone. The size of the device is 2 cm × 2 cm × 1 mm. RESULTS: Colorimetric detection of human IgG was accomplished at 100 fg/mL concentration using a gold nanoparticle-conjugated anti-human IgG antibody. The developed platform has a dynamic range of IgM and IgG concentrations between 0.1 pg/mL and 100 µg/mL. These devices provided a color readout in <5 minutes using 20 µL of serum. We also demonstrated that the devices show a significant degree of ruggedness and temperature stability as they were able to provide satisfactory results (detection of 0.1 pg/mL IgG) after 14 days of long stability and shelf-life experiment at an elevated temperature of at least 50 ˚C-the shelf life can be as long as 180 days under ambient conditions for detection of 100 µg/mL IgG. CONCLUSIONS: Because of the inherent simplicity of the device operation and their ease of use, there is no variation between samples and users of the device. This low-cost approach enables multiplexing with >1 measurement performed in parallel at the same time. We anticipate that because of the sensitivity, specificity, ease of use, and overall reliability, this approach will become a standard for diagnosis of diseases and health conditions.


Subject(s)
Microfluidics , Gold , Humans , Immunoassay , Metal Nanoparticles , Reproducibility of Results
6.
Acta Cardiol ; 76(5): 475-485, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33146076

ABSTRACT

AIMS: The objective of this study is to assess the prognostic effects of T ranscatheter aortic valve replacement (TAVR) on the patients with different degrees of left ventricular systolic (LVS) function and severe symptomatic aortic stenosis. Also examines the prognostic association of LV remodelling after TAVR. METHODS AND RESULTS: Patients stratified into four subgroups with respect to baseline LV ejection fraction (LVEF) (LVEF > 25%, LVEF 25%-40%, LVEF 41%-49% and LVEF ≥ 50%). We compared the baseline characteristics and temporal changes in echocardiographic parameters of the patients after TAVR, and determined all-cause mortality (ACM) in a follow-up period of mean 20.7 ± 15.8 months (up to 84). There were 495 patients at 8 centres. ACM was similar in all groups (28.1%, 29.5%, 22.5% and 24.1% respectively; p = .44). Immediately after TAVR, there was an improvement in LVEF (from 38.7 ± 9.4 to 44.9% ± 10.9%, p < .001). The percent change in LVEF (pDelta-EF) immediately after TAVR was more prominent in the patients with LVEF < 25% (48.1 ± 49.6, 21.9 ± 29.6), (8.4% ± 15.2%) and (2.1 ± 7)) (p < .01). Importantly, a 12% increase in absolute Delta-EF was observed in patients with LVEF< 25% with 100% sensitivity and 42.5% specificity for the prediction of ACM. CONCLUSION: This study shows that TAVR is beneficial in the whole range of LVS function, irrespective of the baseline EF. Early recovery in LVEF after TAVR is critical for survival, however, it seems to be more eye catching in the patients with advanced heart failure with reduced EF.


Subject(s)
Aortic Valve Stenosis , Transcatheter Aortic Valve Replacement , Ventricular Dysfunction, Left , Aortic Valve/surgery , Aortic Valve Stenosis/diagnosis , Aortic Valve Stenosis/surgery , Humans , Retrospective Studies , Stroke Volume , Treatment Outcome , Ventricular Dysfunction, Left/diagnosis , Ventricular Function, Left
7.
Adv Healthc Mater ; 8(14): e1900244, 2019 07.
Article in English | MEDLINE | ID: mdl-31081270

ABSTRACT

Lateral flow assays (LFAs) have been the pillar of rapid point-of-care (POC) diagnostics due to their simplicity, rapid process, and low cost. Recent advances in sensitivity, selectivity, and chemical stability enhancement have ensured the foothold of LFAs in commercial POC diagnostics. This paper reviews recent developments in labeling strategies and detection methods of LFAs. Moreover, vertical flow assays (VFAs) have emerged as an alternate paper-based assay due to faster detection time and unique multiplexing capabilities. Smartphones as LFA readers have been transformed into a universal integrated platform for imaging, data processing, and storage, providing quantitative results in low-resource settings. Commercial LFAs and VFAs products are evaluated with regards to their performance, market trends, and regulatory issues. The future outlook of the flow-based assays for POC diagnostics is also discussed.


Subject(s)
Biological Assay/methods , Point-of-Care Systems , Rheology/methods , Animals , Humans , Nanofibers/chemistry , Quantum Dots/chemistry , Smartphone
8.
Trends Biotechnol ; 37(6): 563-566, 2019 06.
Article in English | MEDLINE | ID: mdl-30851983

ABSTRACT

Wearable medical devices (WMDs) will advance point-of-care diagnostics and therapeutics. This article analyses the market and patents for wearable devices. Activity monitors have the largest market share, and the intellectual property landscape is dominated by electronics corporations. However, the majority of these patents have not been realized in commercial products.


Subject(s)
Biomedical Technology , Fitness Trackers , Patents as Topic , Wearable Electronic Devices , Biomedical Technology/economics , Biomedical Technology/instrumentation , Biomedical Technology/legislation & jurisprudence , Fitness Trackers/economics , Fitness Trackers/statistics & numerical data , Humans , Wearable Electronic Devices/economics , Wearable Electronic Devices/statistics & numerical data
9.
Adv Mater ; : e1706910, 2018 Jun 11.
Article in English | MEDLINE | ID: mdl-29893068

ABSTRACT

Wearables as medical technologies are becoming an integral part of personal analytics, measuring physical status, recording physiological parameters, or informing schedule for medication. These continuously evolving technology platforms do not only promise to help people pursue a healthier life style, but also provide continuous medical data for actively tracking metabolic status, diagnosis, and treatment. Advances in the miniaturization of flexible electronics, electrochemical biosensors, microfluidics, and artificial intelligence algorithms have led to wearable devices that can generate real-time medical data within the Internet of things. These flexible devices can be configured to make conformal contact with epidermal, ocular, intracochlear, and dental interfaces to collect biochemical or electrophysiological signals. This article discusses consumer trends in wearable electronics, commercial and emerging devices, and fabrication methods. It also reviews real-time monitoring of vital signs using biosensors, stimuli-responsive materials for drug delivery, and closed-loop theranostic systems. It covers future challenges in augmented, virtual, and mixed reality, communication modes, energy management, displays, conformity, and data safety. The development of patient-oriented wearable technologies and their incorporation in randomized clinical trials will facilitate the design of safe and effective approaches.

10.
Ann Noninvasive Electrocardiol ; 23(5): e12558, 2018 09.
Article in English | MEDLINE | ID: mdl-29873439

ABSTRACT

BACKGROUND: To our knowledge, no study so far investigated the importance of post-procedural frontal QRS-T angle f(QRS-T) in ST segment elevation myocardial infarction (STEMI). The aim of our study was to investigate the role of baseline and post-procedural f(QRS-T) angles for determining high risk STEMI patients, and the success of reperfusion. METHODS: A total of 248 patients with first acute STEMI that underwent primary percutaneous coronary intervention (pPCI) or thrombolytic therapy (TT) between 2013 and 2014 were included in this study. Baseline f(QRS-T) angle was defined as the angle which measured from the first ECG at the time of hospital admission. Post-procedural (QRS-T) angle was defined according to the treatment strategy as follows: the angle which measured from the post-PCI ECG in patients treated with pPCI; the angle which measured from the ECG taken 90 min after onset of therapy in patients treated with TT. RESULTS: The baseline (101.9° ± 48.0 vs. 72.1° ± 49.1, p = 0.014) and post-procedural f(QRS-T) angles (95.7° ± 48.1 vs. 58.1° ± 47.1, p = 0.002) were significantly higher in patients who developed in-hospital mortality than the patients who did not develop in-hospital mortality. Also, f(QRS-T) angle measured at 90 min was significantly lower in patients with successful thrombolysis group compared to failed thrombolysis group (53.2° ± 42.8 vs. 77.3° ± 52.9, p = 0.033), whereas baseline f(QRS-T) angle was similar between two groups (78.6° ± 53.4 vs. 78.9° ± 54.0, p = 0.976). Multivariate analysis showed that post-procedural f(QRS-T) angle ≥89.6° (odds ratio: 3.541, 95% confidence interval: 1.235-10.154, p = 0.019), but not baseline f(QRS-T) angle, was independent predictor of in-hospital mortality. CONCLUSION: f(QRS-T) angle may be used as a beneficial tool for determining high risk patients in acute STEMI. Unlike previous studies, we showed for the first time that that post-procedural f(QRS-T) can predict in-hospital mortality and TT failure.


Subject(s)
Electrocardiography/methods , Percutaneous Coronary Intervention/methods , ST Elevation Myocardial Infarction/physiopathology , ST Elevation Myocardial Infarction/therapy , Thrombolytic Therapy/methods , Coronary Angiography/methods , Female , Humans , Male , Middle Aged , Retrospective Studies , Risk Assessment , ST Elevation Myocardial Infarction/diagnostic imaging
11.
Clin Exp Hypertens ; 40(4): 318-323, 2018.
Article in English | MEDLINE | ID: mdl-28949780

ABSTRACT

BACKGROUND: Frontal QRS-T angle is a novel marker of myocardial repolarization, and an increased frontal QRS-T angle associated with adverse cardiac outcomes. Non-dipper hypertension is also associated with adverse cardiac outcomes. This study aimed to investigate the relationship between frontal QRS-T angle and non-dipper status in hypertensive patients without left ventricular hypertrophy (LVH). METHODS: This study included 122 hypertensive patients without LVH. Patients were divided into two groups: dipper hypertension and non-dipper hypertension. The frontal QRS-T angle was calculated from 12-lead electrocardiography. RESULTS: Frontal QRS-T angle (47.9° ± 29.7° vs. 26.7° ± 19.6°, P < 0.001) was significantly higher in patients with non-dipper hypertension than in patients with dipper hypertension. In addition, frontal QRS-T angle was positively correlated with sleeping systolic (r = 0.211, P = 0.020), and diastolic (r = 0.199, P = 0.028) blood pressures (BP), even if they were weak. Multivariate analysis showed that the frontal QRS-T angle was independent predictor of non-dipper status (QR: 1.037, 95% CI: 1.019-1.056, P < 0.001). CONCLUSION: Frontal QRS-T angle is independent predictor of non-dipper status in hypertensive patients without LVH.


Subject(s)
Blood Pressure , Circadian Rhythm/physiology , Heart/physiopathology , Hypertension/physiopathology , Adult , Aged , Diastole , Electrocardiography , Female , Humans , Hypertrophy, Left Ventricular/physiopathology , Male , Middle Aged , Sleep/physiology , Systole
12.
Turk Gogus Kalp Damar Cerrahisi Derg ; 26(1): 65-72, 2018 Jan.
Article in English | MEDLINE | ID: mdl-32082713

ABSTRACT

BACKGROUND: In this study, we aimed to investigate the effect of transcatheter aortic valve implantation using two types of bioprosthetic valves on novel ventricular repolarization markers including Tp-e, Tp-e/QT and Tpe/QTc ratios, and Tp-ed. METHODS: A total of 61 patients (17 males, 44 females; mean age 78.6±6.5 years; range 55 to 89 years) who underwent transcatheter aortic valve implantation with either a Medtronic CoreValve (n=40) or an Edwards SAPIEN XT valve (n=21) were retrospectively analyzed. The electrocardiographic parameters and left ventricular mass index were calculated prior to the procedure, on postoperative Day 1, and at three months after the procedure. RESULTS: The Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, Tp-ed, and left ventricular mass index significantly reduced at three months of the procedure, compared to baseline values (p<0.01, for all). Similar findings were observed for QT, QTc, and QT dispersion (p<0.01, for all). These changes were independent from the types of bioprosthetic valves used. Before the procedure, the left ventricular mass index was positively correlated with the Tp-e (r=0.350, p=0.007), Tp-e/QT (r=0.314, p=0.015) and Tp-e/QTc ratios (r=0.285, p=0.029). In the multivariate analysis, Tp-e interval was found to be independently associated with the left ventricular mass index (b=0.350, p=0.007). CONCLUSION: In the present study, the Tp-e interval, Tp-e/QT and Tp-e/QTc ratios, Tp-ed, and left ventricular mass index significantly reduced at three months after transcatheter aortic valve implantation indicating reverse left ventricular remodeling. The effects of two types of bioprosthetic valves on ventricular repolarization markers and left ventricular mass index were similar.

13.
J Electrocardiol ; 51(2): 210-217, 2018.
Article in English | MEDLINE | ID: mdl-29117907

ABSTRACT

BACKGROUND: No study has investigated the prognostic importance of the combined use of QRS distortion and fragmented QRS (fQRS) for risk stratification in acute ST segment elevation myocardial infarction (STEMI). OBJECTIVE: To determine the prognostic value of the combined use of QRS distortion and fQRS in patients with acute STEMI undergoing primary percutaneous coronary intervention (pPCI). METHODS: A total of 454 patients with first STEMI who underwent pPCI were included in this study. Patients were categorized into three groups according to the presence of QRS distortion and fQRS on admission electrocardiography. Group I was defined as fQRS (-) and QRS distortion (-), group 2 was defined as fQRS (+) and QRS distortion (-), or fQRS (-) and QRS distortion (+), and group 3 was defined as both fQRS (+) and QRS distortion (+). RESULTS: Patients in group III had a significantly higher in-hospital mortality rate compared with patients in groups I and II. These patients also had lower left ventricular ejection fraction and ST resolution ratios, higher maximum troponin, and higher frequency of three-vessel disease. Multivariate analysis indicated that group III (OR: 8.84, 95% CI: 2.73-28.62, p<0.001) was an independent predictors of in-hospital mortality. CONCLUSION: The combined use of QRS distortion and fQRS provides additional prognostic value compared with the presence of QRS distortion or fQRS alone for early risk stratification in patients with STEMI treated with pPCI.


Subject(s)
Electrocardiography , Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction/physiopathology , ST Elevation Myocardial Infarction/surgery , Biomarkers/blood , Female , Hospital Mortality , Humans , Male , Middle Aged , Prognosis , Risk Assessment , Risk Factors , ST Elevation Myocardial Infarction/mortality
14.
Soft Robot ; 4(3): 183-190, 2017 Sep.
Article in English | MEDLINE | ID: mdl-29182080

ABSTRACT

This article describes a class of robots-"arthrobots"-inspired, in part, by the musculoskeletal system of arthropods (spiders and insects, inter alia). Arthrobots combine mechanical compliance, lightweight and simple construction, and inexpensive yet scalable design. An exoskeleton, constructed from thin organic polymeric tubes, provides lightweight structural support. Pneumatic joints modeled after the hydrostatic joints of spiders provide actuation and inherent mechanical compliance to external forces. An inflatable elastomeric tube (a "balloon") enables active extension of a limb; an opposing elastic tendon enables passive retraction. A variety of robots constructed from these structural elements demonstrate (i) crawling with one or two limbs, (ii) walking with four or six limbs (including an insect-like triangular gait), (iii) walking with eight limbs, or (iv) floating and rowing on the surface of water. Arthrobots are simple to fabricate and are able to operate safely in contact with humans.


Subject(s)
Robotics/instrumentation , Animals , Arthropods/physiology , Biomechanical Phenomena , Elastomers , Equipment Design , Exoskeleton Device , Movement , Polymers
15.
Adv Healthc Mater ; 6(22)2017 Nov.
Article in English | MEDLINE | ID: mdl-29076283

ABSTRACT

Paper is used in various applications in biomedical research including diagnostics, separations, and cell cultures. Paper can be conveniently engineered due to its tunable and flexible nature, and is amenable to high-throughput sample preparation and analysis. Paper-based platforms are used to culture primary cells, tumor cells, patient biopsies, stem cells, fibroblasts, osteoblasts, immune cells, bacteria, fungi, and plant cells. These platforms are compatible with standard analytical assays that are typically used to monitor cell behavior. Due to its thickness and porous nature, there are no mass transport limitations to/from the cells in paper scaffolds. It is possible to pattern paper in different scales (micrometer to centimeter), generate modular configurations in 3D, fabricate multicellular and compartmentalized tissue mimetics for clinical applications, and recover cells from the scaffolds for further analysis. 3D paper constructs can provide physiologically relevant tissue models for personalized medicine. Layer-by layer strategies to assemble tissue-like structures from low-cost and biocompatible paper-based materials offer unique opportunities that include understanding fundamental biology, developing disease models, and assembling different tissues for organ-on-paper applications. Paper-based platforms can also be used for origami-inspired tissue engineering. This work provides an overview of recent progress in engineered paper-based biomaterials and platforms to culture and analyze cells.


Subject(s)
Cell Culture Techniques/instrumentation , Cell Culture Techniques/methods , Tissue Engineering/instrumentation , Tissue Engineering/methods , Animals , Biocompatible Materials/chemistry , Biomimetics/instrumentation , Biomimetics/methods , Humans , Paper , Tissue Scaffolds/chemistry
16.
Lab Chip ; 16(20): 3885-3897, 2016 10 05.
Article in English | MEDLINE | ID: mdl-27714038

ABSTRACT

This communication describes the use of uncoated cellophane (regenerated cellulose films) for the fabrication of microplates, and the use of coated cellophane for the fabrication of open-channel microfluidic devices. The microplates based on uncoated cellophane are particularly interesting for applications that require high transparency in the ultraviolet (UV) regime, and offer a low-cost alternative to expensive quartz-well plates. Uncoated cellophane is also resistant to damage by various solvents. The microfluidic devices, based on coated cellophane, can have features with dimensions as small as 500 µm, and complex, non-planar geometries. Electrodes can be printed on the surface of the coated cellophane, and embedded in microfluidic devices, to develop resistive heaters and electroanalytical devices for flow injection analysis, and continuous flow electrochemiluminescence (ECL) applications. These open-channel devices are appropriate for applications where optical transparency (especially in the visible regime), resistance to damage by water, biocompatibility and biodegradability are important. Cellophane microfluidic systems complement existing cellulose-based paper microfluidic systems, and provide an alternative to other materials used in microfluidics, such as synthetic polymers or glass. Cellulose films are plausible materials for uses in integrated microfluidic systems for diagnostics, analyses, cell-culture, and MEMS.

17.
Ann Noninvasive Electrocardiol ; 20(6): 578-85, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25640307

ABSTRACT

BACKGROUND: QRS fragmentation (fQRS) and QRS distortion were separately shown to be related to increased cardiovascular mortality and morbidity. To our knowledge, no study so far evaluated both parameters together in ST segment elevation myocardial infarction (STEMI). The main goal of our study is to find out if fQRS and QRS distortion can help us to determine high-risk STEMI patients, and the success of reperfusion. METHODS: Two hundred forty-eight eligible patients with acute STEMI that underwent coronary angiography consecutively between January 1, 2009, and July 1, 2011, were enrolled in this study. Twelve-lead electrocardiography (ECG) of the patients taken in the first 48 hours were analyzed. Patients with fQRS formed group 1, without fQRS formed group 2; with QRS distortion formed group 3, and without QRS distortion formed group 4. RESULTS: Group 1 have lower left ventricular ejection fraction (LVEF; P < 0.001), higher maximum troponin levels (P < 0.001), lower ST segment resolution (P < 0.001), more frequent proximal lesions (P < 0.001) when compared to group 2. Similar findings were observed in group 3 in comparison to group 4. Group 1 had also more frequent three vessels disease (P < 0.001), and higher rates of failed thrombolysis (P < 0.001). In-hospital mortality was found to be higher in group 1 and group 3. CONCLUSION: fQRS and QRS distortion may be useful for identifying patients at higher cardiac risk. fQRS can foresee thrombolytic therapy failure and three vessels disease whereas QRS distortion does not possess such quality. These findings may guide the physician deciding initial treatment modality in STEMI.


Subject(s)
Electrocardiography , Myocardial Infarction/diagnosis , Myocardial Infarction/therapy , Percutaneous Coronary Intervention , Thrombolytic Therapy , Aged , Coronary Angiography , Female , Humans , Male , Middle Aged , Myocardial Reperfusion , Predictive Value of Tests , Retrospective Studies , Risk
18.
Langmuir ; 30(41): 12391-9, 2014 Oct 21.
Article in English | MEDLINE | ID: mdl-25263163

ABSTRACT

The fabrication of micrometer-sized core-shell particles for ultrasound-triggered delivery offers a variety of applications in medical research. In this work, we report the design and development of a glass capillary microfluidic system containing three concentric glass capillary tubes for the development of core-shell particles. The setup enables the preparation of perfluorocarbon-alginate core-shell microspheres in a single process, avoiding the requirement for further extensive purification steps. Core-shell microspheres in the range of 110-130 µm are prepared and are demonstrated to be stable up to 21 days upon immersion in calcium chloride solution or water. The mechanical stability of the particles is tested by injecting them through a 23 gauge needle into a polyacrylamide gel to mimic the tissue matrix. The integrity of the particles is maintained after the injection process and is disrupted after ultrasound exposure for 15 min. The results suggest that the perfluorcarbon-alginate microparticles could be a promising system for the delivery of compounds, such as proteins, peptides, and small-molecule drugs in ultrasound-based therapies.


Subject(s)
Alginates/chemical synthesis , Fluorocarbons/chemical synthesis , Microfluidic Analytical Techniques , Microspheres , Ultrasonic Therapy , Alginates/chemistry , Fluorocarbons/chemistry , Particle Size , Surface Properties
19.
Phys Rev Lett ; 108(21): 216102, 2012 May 25.
Article in English | MEDLINE | ID: mdl-23003283

ABSTRACT

The formation of a new type of ordered 2D Ni3Al overlayer by low-temperature codeposition on NiAl(110) is demonstrated by kinetic Monte Carlo simulation of a multisite atomistic lattice-gas model with a precise treatment of surface diffusion kinetics. Simultaneous codeposition with 3:1 Ni:Al yields poor ordering at 300 K but well-ordered structures by ~500 K. Sequential codeposition of Ni then Al yields unmixed core-ring nanostructures at 300 K but strong intermixing and ordering by ~500 K.

20.
J Chem Phys ; 135(8): 084706, 2011 Aug 28.
Article in English | MEDLINE | ID: mdl-21895213

ABSTRACT

Scanning tunneling microscopy studies reveal that two-dimensional nanoscale Ni islands formed by deposition of Ni on NiAl(110) between 200-400 K exhibit far-from-equilibrium growth shapes which change systematically with temperature. Island structure reflects the two types of adsorption sites available for Ni adatoms, and island shapes are controlled by the details of adatom diffusion along island edges accounting for numerous local configurations. The temperature dependence of the island shapes is captured and elucidated by kinetic Monte Carlo simulation of a realistic atomistic-level multisite lattice-gas model incorporating precise diffusion barriers. These barriers are obtained by utilizing density functional theory to probe energetics not just at adsorption sites but also at transition states for diffusion. This success demonstrates a capability for predictive atomistic-level modeling of nanocluster formation and shape selection in systems that have a high level of energetic and kinetic complexity.

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