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Shahub S, Kumar RM, Lin KC, Banga I, Choi NK, Garcia NM, Muthukumar S, Rubin DT, Prasad S. Continuous Monitoring of CRP, IL-6, and Calprotectin in Inflammatory Bowel Disease Using a Perspiration-Based Wearable Device. Inflamm Bowel Dis 2024:izae054. [PMID: 38520737 DOI: 10.1093/ibd/izae054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Indexed: 03/25/2024]
Abstract
BACKGROUND Wearable sensor devices represent a noninvasive technology to continuously track biomarkers linked to inflammatory bowel disease (IBD). We assessed the inflammatory markers associated with IBD in human perspiration. METHODS Participants with IBD were monitored for 40 to 130 minutes with a proprietary wearable sensor device used to measure C-reactive protein, interleukin-6, and calprotectin. Sensor response using electrochemical impedance spectroscopy and serum samples were measured on the same day. The Mann-Whitney test was used to analyze the relationship between active and remission IBD in serum and perspiration, classified according to endoscopic reports and serum biomarker levels. Asynchronously collected fecal calprotectin from a subset of the population was similarly analyzed. RESULTS A total of 33 subjects were enrolled. Expression of calprotectin was significantly elevated in the active cohort compared with the remission cohort in perspiration (P < .05; median = 906.69 ng/mL; active 95% confidence interval [CI], 466.0-1833 ng/mL; remission 95% CI, 328.4-950.8 ng/mL), serum (median = 1860.82 ng/mL; active 95% CI, 1705-2985 ng/mL; remission 95% CI, 870.2-1786 ng/mL), and stool (P < .05; median = 126.74 µg/g; active 95% CI, 77.08-347.1 µg/g; remission 95% CI, 5.038-190.4 µg/g). Expression of CRP in perspiration and serum was comparable between the active and remission cohorts (perspiration: P > .05; median = 970.83 pg/mL; active 95% CI, 908.7-992 pg/mL; remission 95% CI, 903.3-991.9 pg/mL; serum: median = 2.34 µg/mL; active 95% CI, 1.267-4.492 µg/mL; remission 95% CI, 1.648-4.287 µg/mL). Expression of interleukin-6 in perspiration was nonsignificant in the active cohort compared with the remission cohort and was significantly elevated in serum (perspiration: P < .05; median = 2.13 pg/mL; active 95% CI, 2.124-2.44 pg/mL; remission 95% CI, 1.661-2.451 pg/mL; serum: median = 1.15 pg/mL; active 95% CI, 1.549-3.964 pg/mL; remission 95% CI, 0.4301-1.257 pg/mL). Analysis of the linear relationship between perspiration and serum calprotectin (R2 = 0.7195), C-reactive protein (R2 = 0.615), and interleukin-6 (R2 = 0.5411) demonstrated a strong to moderate relationship across mediums. CONCLUSIONS We demonstrate the clinical utility of perspiration as a noninvasive medium for continuous measurement of inflammatory markers in IBD and find that the measures correlate with serum and stool markers across a range of disease activity.
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Affiliation(s)
- Sarah Shahub
- Department of Bioengineering, University of Texas at Dallas, Dallas, TX, USA
| | | | - Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, Dallas, TX, USA
| | - Ivneet Banga
- Department of Bioengineering, University of Texas at Dallas, Dallas, TX, USA
| | - Natalie K Choi
- Inflammatory Bowel Disease Center, University of Chicago Medicine, Chicago, IL, USA
| | - Nicole M Garcia
- Inflammatory Bowel Disease Center, University of Chicago Medicine, Chicago, IL, USA
| | | | - David T Rubin
- Inflammatory Bowel Disease Center, University of Chicago Medicine, Chicago, IL, USA
| | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, Dallas, TX, USA
- EnLiSense LLC, Allen, TX, United States
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Hirten RP, Lin KC, Whang J, Shahub S, Helmus D, Muthukumar S, Sands BE, Prasad S. Longitudinal assessment of sweat-based TNF-alpha in inflammatory bowel disease using a wearable device. Sci Rep 2024; 14:2833. [PMID: 38310197 PMCID: PMC10838338 DOI: 10.1038/s41598-024-53522-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Accepted: 02/01/2024] [Indexed: 02/05/2024] Open
Abstract
Wearable devices can non-invasively monitor patients with chronic diseases. Sweat is an easily accessible biofluid for continuous sampling of analytes, including inflammatory markers and cytokines. We evaluated a sweat sensing wearable device in subjects with and without inflammatory bowel disease (IBD), a chronic inflammatory condition of the gastrointestinal tract. Participants with an IBD related hospital admission and a C-reactive protein level above 5 mg/L wore a sweat sensing wearable device for up to 5 days. Tumor necrosis factor-alpha (TNF-α) levels were continually assessed in the sweat via the sensor, and daily in the blood. A second cohort of healthy subjects without chronic diseases wore the device for up to 48 h. Twenty-eight subjects were enrolled. In the 16 subjects with IBD, a moderate linear relationship between serum and sweat TNF-α levels was observed (R2 = 0.72). Subjects with IBD were found to have a mean sweat TNF-α level of 2.11 pg/mL, compared to a mean value of 0.19 pg/mL in 12 healthy controls (p < 0.0001). Sweat TNF-α measurements differentiated subjects with active IBD from healthy subjects with an AUC of 0.962 (95% CI 0.894-1.000). A sweat sensing wearable device can longitudinally measure key sweat-based markers of IBD. TNF-α levels in the sweat of subjects with IBD correlate with serum values, suggesting feasibility in non-invasive disease monitoring.
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Affiliation(s)
- Robert P Hirten
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kai-Chun Lin
- Bioengineering, University of Texas at Dallas, 800 West Campbell Rd., Richardson, TX, 75080-3021, USA
| | - Jessica Whang
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sarah Shahub
- Bioengineering, University of Texas at Dallas, 800 West Campbell Rd., Richardson, TX, 75080-3021, USA
| | - Drew Helmus
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Bruce E Sands
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Shalini Prasad
- Bioengineering, University of Texas at Dallas, 800 West Campbell Rd., Richardson, TX, 75080-3021, USA.
- EnLiSense LLC, Allen, TX, USA.
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Hirten RP, Lin KC, Whang J, Shahub S, Churcher NK, Helmus D, Muthukumar S, Sands B, Prasad S. Longitudinal monitoring of IL-6 and CRP in inflammatory bowel disease using IBD-AWARE. Biosens Bioelectron X 2024; 16:100435. [PMID: 38317723 PMCID: PMC10843811 DOI: 10.1016/j.biosx.2023.100435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
There are limitations to monitoring modalities for chronic inflammatory conditions, including inflammatory bowel disease (IBD). Wearable devices are scalable mobile health technology that present an opportunity to monitor markers that have been linked to worsening, chronic inflammatory conditions and enable remote monitoring. In this research article, we evaluate and demonstrate a proof-of-concept wearable device to longitudinally monitor inflammatory and immune markers linked to IBD disease activity in sweat compared to expression in serum. Sixteen participants with an IBD-related hospital admission and a C-reactive protein (CRP) > 5 μg/mL were followed for up to 5 days. The sweat sensing device also known as IBD AWARE was worn to continuously measure CRP and interleukin-6 (IL-6) in the sweat of participants via electrochemical impedance spectroscopy. Serum samples were collected daily. A linear relationship between serum and sweat readings for CRP and IL-6 was demonstrated based on individual linear correlation coefficients. Pooled CRP and IL-6 serum-to-sweat ratios demonstrated improving correlation coefficients as serum cutoffs decreased. Between the first and last day of observation, significant and non-significant trends in serum CRP and IL-6 were observed in the sweat. Comparison of sweat measurements between the subjects with active IBD and 10 healthy subjects distinguished an inflamed and uninflamed state with an AUC of 0.85 (95% CI: 0.68-1.00) and a sensitivity and specificity of 82% and 70% at a CRP cutoff of 938.9 pg/mL. IBD AWARE wearable device holds promise in longitudinally monitoring individuals with IBD and other inflammatory diseases.
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Affiliation(s)
- Robert P. Hirten
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Kai-Chun Lin
- Department of Bioengineering Engineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Jessica Whang
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sarah Shahub
- Department of Bioengineering Engineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Nathan K.M. Churcher
- Department of Bioengineering Engineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Drew Helmus
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | | | - Bruce Sands
- The Dr. Henry D. Janowitz Division of Gastroenterology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Shalini Prasad
- Department of Bioengineering Engineering, The University of Texas at Dallas, Richardson, TX, USA
- EnLiSense LLC, Allen, TX, USA
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Greyling CF, Ganguly A, Sardesai AU, Churcher NKM, Lin KC, Muthukumar S, Prasad S. Passive sweat wearable: A new paradigm in the wearable landscape toward enabling "detect to treat" opportunities. Wiley Interdiscip Rev Nanomed Nanobiotechnol 2024; 16:e1912. [PMID: 37356818 DOI: 10.1002/wnan.1912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 04/11/2023] [Accepted: 05/27/2023] [Indexed: 06/27/2023]
Abstract
Growing interest over recent years in personalized health monitoring coupled with the skyrocketing popularity of wearable smart devices has led to the increased relevance of wearable sweat-based sensors for biomarker detection. From optimizing workouts to risk management of cardiovascular diseases and monitoring prediabetes, the ability of sweat sensors to continuously and noninvasively measure biomarkers in real-time has a wide range of applications. Conventional sweat sensors utilize external stimulation of sweat glands to obtain samples, however; this stimulation influences the expression profile of the biomarkers and reduces the accuracy of the detection method. To address this limitation, our laboratory pioneered the development of the passive sweat sensor subfield, which allowed for our progress in developing a sweat chemistry panel. Passive sweat sensors utilize nanoporous structures to confine and detect biomarkers in ultra-low sweat volumes. The ability of passive sweat sensors to use smaller samples than conventional sensors enable users with sedentary lifestyles who perspire less to benefit from sweat sensor technology not previously afforded to them. Herein, the mechanisms and strategies of current sweat sensors are summarized with an emphasis on the emerging subfield of passive sweat-based diagnostics. Prospects for this technology include discovering new biomarkers expressed in sweat and expanding the list of relevant detectable biomarkers. Moreover, the accuracy of biomarker detection can be enhanced with machine learning using prediction algorithms trained on clinical data. Applying this machine learning in conjunction with multiplex biomarker detection will allow for a more holistic approach to trend predictions. This article is categorized under: Diagnostic Tools > Diagnostic Nanodevices Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Diagnostic Tools > Biosensing.
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Affiliation(s)
| | - Antra Ganguly
- Department of Bioengineering, The University of Texas at Dallas, Richardson, Texas, USA
| | - Abha Umesh Sardesai
- Department of Computer Engineering, The University of Texas at Dallas, Richardson, Texas, USA
| | | | - Kai-Chun Lin
- Department of Bioengineering, The University of Texas at Dallas, Richardson, Texas, USA
| | | | - Shalini Prasad
- Department of Bioengineering, The University of Texas at Dallas, Richardson, Texas, USA
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Chen J, Lin KC, Prasad S, Schmidtke DW. Label free impedance based acetylcholinesterase enzymatic biosensors for the detection of acetylcholine. Biosens Bioelectron 2023; 235:115340. [PMID: 37216844 DOI: 10.1016/j.bios.2023.115340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/08/2023] [Accepted: 04/18/2023] [Indexed: 05/24/2023]
Abstract
Realtime monitoring of neurotransmitters is of great interest for understanding their fundamental role in a wide range of biological processes in the central and peripheral nervous system, as well as their role, in several degenerative brain diseases. The measurement of acetylcholine in the brain is particularly challenging due to the complex environment of the brain and the low concentration and short lifetime of acetylcholine. In this paper, we demonstrated a novel, label-free biosensor for the detection of Ach using a single enzyme, acetylcholinesterase (ACHE), and electrochemical impedance spectroscopy (EIS). Acetylcholinesterase was covalently immobilized onto the surface of gold microelectrodes through an amine-reactive crosslinker dithiobis(succinimidyl propionate) (DSP). Passivation of the gold electrode with SuperBlock eliminated or reduced any non-specific response to other major interfering neurotransmitter molecules such as dopamine (DA), norepinephrine (NE) and epinephrine (EH). The sensors were able to detect acetylcholine over a wide concentration range (5.5-550 μM) in sample volumes as small as 300 μL by applying a 10 mV AC voltage at a frequency of 500 Hz. The sensors showed a linear relationship between Ach concentration and ΔZmod(R2 = 0.99) in PBS. The sensor responded to acetylcholine not only when evaluated in a simple buffer (PBS buffer) but in several more complex environments such as rat brain slurry and rat whole blood. The sensor remained responsive to acetylcholine after being implanted ex vivo in rat brain tissue. These results bode well for the future application of these novel sensors for real time in vivo monitoring of acetylcholine.
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Affiliation(s)
- Jie Chen
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Rd, Richardson, TX, 75083, USA
| | - Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Rd, Richardson, TX, 75083, USA
| | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Rd, Richardson, TX, 75083, USA.
| | - David W Schmidtke
- Department of Bioengineering, University of Texas at Dallas, 800 W. Campbell Rd, Richardson, TX, 75083, USA.
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Upasham S, Pali M, Jagannath B, Lin KC, Prasad S. Electrochemical Aptasensing for Lifestyle and Chronic Disease Management. Curr Med Chem 2023; 30:895-909. [PMID: 35619314 DOI: 10.2174/0929867329666220520111715] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 01/21/2022] [Accepted: 03/10/2022] [Indexed: 11/22/2022]
Abstract
Over the past decade, researchers have investigated electrochemical sensing for the purpose of fabricating wearable point-of-use platforms. These wearable platforms have the ability to non-invasively track biomarkers that are clinically relevant and provide a comprehensive evaluation of the user's health. Due to many significant operational advantages, aptamer-based sensing is gaining traction.Aptamer-based sensors have properties like long-term stability, resistance to denaturation, and high sensitivity. Using electrochemical sensing with aptamer-based biorecognition is advantageous because it provides significant benefits like lower detection limits, a wider range of operations, and, most importantly, the ability to detect using a label-free approach. This paper provides an outlook into the current state of electrochemical aptasensing. This review looks into the significance of the detection of biomarkers like glucose, cortisol etc., for the purpose of lifestyle and chronic disease monitoring. Moreover, this review will also provide a comprehensive evaluation of the current challenges and prospects in this field.
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Affiliation(s)
- Sayali Upasham
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas-75080, USA
| | - Madhavi Pali
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas-75080, USA
| | - Badrinath Jagannath
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas-75080, USA
| | - Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas-75080, USA
| | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, Richardson, Texas-75080, USA
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Shahub S, Lin KC, Muthukumar S, Prasad S. A Proof-of-Concept Electrochemical Skin Sensor for Simultaneous Measurement of Glial Fibrillary Acidic Protein (GFAP) and Interleukin-6 (IL-6) for Management of Traumatic Brain Injuries. Biosensors (Basel) 2022; 12:bios12121095. [PMID: 36551062 PMCID: PMC9775589 DOI: 10.3390/bios12121095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/24/2022] [Accepted: 11/27/2022] [Indexed: 05/28/2023]
Abstract
This work demonstrates the use of a noninvasive, sweat-based dual biomarker electrochemical sensor for continuous, prognostic monitoring of a Traumatic Brain Injury (TBI) with the aim of enhancing patient outcomes and reducing the time to treatment after injury. A multiplexed SWEATSENSER was used for noninvasive continuous monitoring of glial fibrillary acidic protein (GFAP) and Interleukin-6 (IL-6) in a human sweat analog and in human sweat. Electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA) were used to measure the sensor response. The assay chemistry was characterized using Fourier Transform Infrared Spectroscopy (FTIR). The SWEATSENSER was able to detect GFAP and IL-6 in sweat over a dynamic range of 3 log orders for GFAP and 2 log orders for IL-6. The limit of detection (LOD) for GFAP detection in the sweat analog was estimated to be 14 pg/mL using EIS and the LOD for IL-6 was estimated to be 10 pg/mL using EIS. An interference study was performed where the specific signal was significantly higher than the non-specific signal. Finally, the SWEATSENSER was able to distinguish between GFAP and IL-6 in simulated conditions of a TBI in human sweat. This work demonstrates the first proof-of-feasibility of a multiplexed TBI marker combined with cytokine and inflammatory marker detection in passively expressed sweat in a wearable form-factor that can be utilized toward better management of TBIs. This is the first step toward demonstrating a noninvasive enabling technology that can enable baseline tracking of an inflammatory response.
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Affiliation(s)
- Sarah Shahub
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Sriram Muthukumar
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
- EnLiSense LLC, Allen, TX 75013, USA
| | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
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Sun C, Lin KC, Yeung CY, Ching ESC, Huang YT, Lai PY, Chan CK. Revealing directed effective connectivity of cortical neuronal networks from measurements. Phys Rev E 2022; 105:044406. [PMID: 35590680 DOI: 10.1103/physreve.105.044406] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 03/23/2022] [Indexed: 06/15/2023]
Abstract
In the study of biological networks, one of the major challenges is to understand the relationships between network structure and dynamics. In this paper, we model in vitro cortical neuronal cultures as stochastic dynamical systems and apply a method that reconstructs directed networks from dynamics [Ching and Tam, Phys. Rev. E 95, 010301(R) (2017)2470-004510.1103/PhysRevE.95.010301] to reveal directed effective connectivity, namely, the directed links and synaptic weights, of the neuronal cultures from voltage measurements recorded by a multielectrode array. The effective connectivity so obtained reproduces several features of cortical regions in rats and monkeys and has similar network properties as the synaptic network of the nematode Caenorhabditis elegans, whose entire nervous system has been mapped out. The distribution of the incoming degree is bimodal and the distributions of the average incoming and outgoing synaptic strength are non-Gaussian with long tails. The effective connectivity captures different information from the commonly studied functional connectivity, estimated using statistical correlation between spiking activities. The average synaptic strengths of excitatory incoming and outgoing links are found to increase with the spiking activity in the estimated effective connectivity but not in the functional connectivity estimated using the same sets of voltage measurements. These results thus demonstrate that the reconstructed effective connectivity can capture the general properties of synaptic connections and better reveal relationships between network structure and dynamics.
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Affiliation(s)
- Chumin Sun
- Institute of Theoretical Physics and Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - K C Lin
- Institute of Theoretical Physics and Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - C Y Yeung
- Institute of Theoretical Physics and Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Emily S C Ching
- Institute of Theoretical Physics and Department of Physics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Yu-Ting Huang
- Department of Physics and Center for Complex Systems, National Central University, Chungli, Taiwan 320, ROC
- Institute of Physics, Academia Sinica, Taipei, Taiwan 115, ROC
| | - Pik-Yin Lai
- Department of Physics and Center for Complex Systems, National Central University, Chungli, Taiwan 320, ROC
| | - C K Chan
- Institute of Physics, Academia Sinica, Taipei, Taiwan 115, ROC
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Pali M, Jagannath B, Lin KC, Upasham S, Sankhalab D, Upashama S, Muthukumar S, Prasad S. CATCH (Cortisol Apta WATCH): ‘Bio-mimic alarm’ to track Anxiety, Stress, Immunity in human sweat. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.138834] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Ganguly A, Lin KC, Muthukumar S, Nagaraj VJ, Prasad S. Label-Free Protein Glycosylation Analysis Using NanoMonitor-An Ultrasensitive Electrochemical Biosensor. Curr Protoc 2021; 1:e150. [PMID: 34101384 DOI: 10.1002/cpz1.150] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Glycans (oligosaccharide chains attached to glycoproteins) are a promising class of biomarkers, found in body fluids such as serum, saliva, urine, etc., that can be used for the diagnosis of disease conditions. Subtle changes in glycans resulting from altered glycosylation machinery have been reported during various diseases, including carcinogenesis. In this article, we detail protocols for the rapid, label-free analysis of glycans using a previously developed highly sensitive and selective electrochemical impedance spectroscopy-based biosensing diagnostic platform called "NanoMonitor." The glycosensor operation is based on the specific affinity capture of the target glycans on the sensor surface by glycan-binding proteins known as lectins. This glycan-lectin binding activity modulates the impedance of the electrical double layer at the buffer-electrode interface. Protocols for the preparation of glycoprotein samples and glycosylation analysis using NanoMonitor and lectin-based ELISA are described here. The data obtained using these protocols show that NanoMonitor is capable of distinguishing between glycoform variants of the glycoprotein fetuin and glycoproteins derived from cultured human pancreatic cancer cells with high sensitivity (orders of magnitude higher than lectin-based ELISA) and selectivity. The results obtained indicate that NanoMonitor protocols can be further developed to enable use of NanoMonitor as a handheld electronic biosensor device for routine multiplexed detection of glycan biomarkers from clinical samples. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Preparing the NanoMonitor surface for glycan biosensing Support Protocol: Synthesis of glycoform variants of fetuin Basic Protocol 2: Performing Electrochemical Impedance Spectroscopy (EIS) for analyzing glycoprotein structures.
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Affiliation(s)
- Antra Ganguly
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, Texas
| | - Kai-Chun Lin
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, Texas
| | | | - Vinay J Nagaraj
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, Texas
| | - Shalini Prasad
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, Texas
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Ali MA, Balaganesh M, Al-Odail FA, Lin KC. Effect of ammonia and water molecule on OH + CH 3OH reaction under tropospheric condition. Sci Rep 2021; 11:12185. [PMID: 34108500 PMCID: PMC8190139 DOI: 10.1038/s41598-021-90640-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 05/05/2021] [Indexed: 11/21/2022] Open
Abstract
The rate coefficients for OH + CH3OH and OH + CH3OH (+ X) (X = NH3, H2O) reactions were calculated using microcanonical, and canonical variational transition state theory (CVT) between 200 and 400 K based on potential energy surface constructed using CCSD(T)//M06-2X/6-311++G(3df,3pd). The results show that OH + CH3OH is dominated by the hydrogen atoms abstraction from CH3 position in both free and ammonia/water catalyzed ones. This result is in consistent with previous experimental and theoretical studies. The calculated rate coefficient for the OH + CH3OH (8.8 × 10-13 cm3 molecule-1 s-1), for OH + CH3OH (+ NH3) [1.9 × 10-21 cm3 molecule-1 s-1] and for OH + CH3OH (+ H2O) [8.1 × 10-16 cm3 molecule-1 s-1] at 300 K. The rate coefficient is at least 8 order magnitude [for OH + CH3OH(+ NH3) reaction] and 3 orders magnitude [OH + CH3OH (+ H2O)] are smaller than free OH + CH3OH reaction. Our calculations predict that the catalytic effect of single ammonia and water molecule on OH + CH3OH reaction has no effect under tropospheric conditions because the dominated ammonia and water-assisted reaction depends on ammonia and water concentration, respectively. As a result, the total effective reaction rate coefficients are smaller. The current study provides a comprehensive example of how basic and neutral catalysts effect the most important atmospheric prototype alcohol reactions.
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Affiliation(s)
- Mohamad Akbar Ali
- Department of Chemistry, College of Science, King Faisal University, PO Box 380, Al Hufuf, 31982, Al-Ahsa, Saudi Arabia.
| | - M Balaganesh
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
| | - Faisal A Al-Odail
- Department of Chemistry, College of Science, King Faisal University, PO Box 380, Al Hufuf, 31982, Al-Ahsa, Saudi Arabia
| | - K C Lin
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
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Bhide A, Lin KC, Muthukumar S, Prasad S. On-demand lactate monitoring towards assessing physiological responses in sedentary populations. Analyst 2021; 146:3482-3492. [PMID: 33955985 DOI: 10.1039/d1an00455g] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Identification of diseases in sedentary populations on a timely basis before reaching a critical stage is a continuing challenge faced by emergency care centers. Lactate is a key biomarker for monitoring restricted oxygen supply essential for assessing the physiological responses of the user for clinical diagnostics. The novelty of this work is the development of a non-invasive, mediator-free, stick and remove biosensor for the on-demand measurement of lactate in passive sweat targeted towards sedentary populations. The conformable interface of the biosensors with skin can be engineered to extract relevant biochemical signals and quantify the in situ sweat biomarker levels. In this work, we demonstrate a highly sensitive and specific on-demand biosensor with a fabricated hybrid nanotextured Au/ZnO electrode stack embedded within a flexible nanoporous material to capture the temporal dynamics of passive sweat lactate. The biosensor exhibits a lactate specific response in human sweat with a 1 mM lower limit of detection and a wide dynamic detection range of 1-100 mM (R2 = 0.98). The proposed biosensor has a sensitivity of 8.3% mM-1 while selectivity studies reveal negative interactions with non-specific molecules. The sensor stability studies showed an ∼30% degradation in the lactate biosensing response over a 4-day duration when stored at 4 °C. Non-faradaic electrochemical spectroscopy is employed as the detection modality to quantify the enzymatic catalysis of sweat lactate at the electrode-sweat interface. Spectroscopic characterization techniques such as XPS, ATR-FTIR, and zeta potential measurements confirm the enzymatic assay binding efficacy on a qualitative scale.
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Affiliation(s)
- Ashlesha Bhide
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX-75080, USA.
| | - Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX-75080, USA.
| | | | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX-75080, USA.
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Upasham S, Bhide A, Lin KC, Prasad S. Point-of-use sweat biosensor to track the endocrine-inflammation relationship for chronic disease monitoring. Future Sci OA 2020; 7:FSO628. [PMID: 33437501 PMCID: PMC7787138 DOI: 10.2144/fsoa-2020-0097] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 08/04/2020] [Indexed: 12/18/2022] Open
Abstract
AIM The hypothalamic-pituitary-adrenal axis is involved in maintaining homeostasis by engaging with the parasympathetic nervous system. During the process of disease affliction, this relationship is disturbed and there is an imbalance driven response observed. MATERIALS & METHODS By monitoring the two key components involved in these pathways, cortisol and TNF-α, the manifestations of chronic stress on the body's homeostasis can be evaluated in a comprehensive manner. This work highlights the development of an electrochemical detection system for the two biomarkers through human sweat. RESULTS Limit of detection and dynamic ranges are 1 ng/ml, 1-200 ng/ml for cortisol and 1 pg/ml, 1-1000 pg/ml for TNF-α. CONCLUSION This wearable system is designed to be a point of use, chronic disease self-monitoring and management platform.
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Affiliation(s)
- Sayali Upasham
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Ashlesha Bhide
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
| | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080, USA
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Jagannath B, Lin KC, Pali M, Sankhala D, Muthukumar S, Prasad S. A Sweat-based Wearable Enabling Technology for Real-time Monitoring of IL-1β and CRP as Potential Markers for Inflammatory Bowel Disease. Inflamm Bowel Dis 2020; 26:1533-1542. [PMID: 32720974 DOI: 10.1093/ibd/izaa191] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND More than 1.2 million people in the United States are affected by inflammatory bowel disease (IBD). Inflammatory bowel disease has a natural course characterized by alternating periods of remission and relapse. Currently, disease flares are unpredictable as they occur in a random way. Further, current testing methods and practices lack the ability for real-time tracking of flares. There exists no technology that can be utilized for continuous monitoring of biomarkers, as most of these rely on samples such as blood, feces, and testing methods by which continuous monitoring is not feasible. Cytokines play a key role in IBD; the development, recurrence, and exacerbation of the inflammatory process are orchestrated by their levels in time and space. Cytokines are also present in sweat. We hypothesize that demonstrating real-time continuous monitoring of interleukin-1β (IL-1β) and C-reactive protein (CRP) may help create an enabling technology to track inflammation in IBD patients and identify flare-ups and assess efficacy of therapy. METHODS A multiplexed SWEATSENSER was used for noninvasive continuous monitoring of interleukin-1β and C-reactive protein in human eccrine sweat. Impedance spectroscopy was used to measure the sensor response. Sweat was collected using an FDA-approved PharmChek patch from 26 healthy human subjects to determine the levels of the 2 study inflammatory markers. Correlation analysis was performed for preclinical validation of the SWEATSENSER with ELISA as the reference method. On-body continuous monitoring measurements were performed on 20 human subjects using EnLiSense's SWEATSENSER wearable device for real-time monitoring studies. RESULTS The sensor device can detect interleukin-1β and C-reactive protein in sweat over a dynamic range of 3 log orders. Pearson correlation of r = 0.99 and r = 0.95 was achieved for IL-1β and CRP, respectively, for the SWEATSENSER with ELISA. Bland-Altman results further confirmed a good agreement (mean bias of -0.25 and -3.9 pg/mL for IL-1β and CRP, respectively) of the device with the reference method, demonstrating applicability of the device for real-time monitoring. Continuous on-body measurements were performed in 20 healthy human subjects for the detection of IL-1β to establish the preclinical utility of the sensor device. The continuous on-body measurements in healthy cohort reported a mean IL-1β concentration of ~28 pg/mL. Stable measurements for over continuous 30 hours was reported by the device. CONCLUSION This work demonstrates the first proof-of-feasibility of multiplexed cytokine and inflammatory marker detection in passively expressed eccrine sweat in a wearable form-factor that can be utilized toward better management of inflammatory bowel disease. This is a first step toward demonstrating a noninvasive enabling technology that can enable baseline tracking of an inflammatory response. Furthermore, this is the first study to report and quantify the presence of CRP in human eccrine sweat.
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Affiliation(s)
- Badrinath Jagannath
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Kai-Chun Lin
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Madhavi Pali
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
| | - Devang Sankhala
- Department of Electrical Engineering, The University of Texas at Dallas, Richardson, TX, USA
| | | | - Shalini Prasad
- Department of Bioengineering, The University of Texas at Dallas, Richardson, TX, USA
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Zhu H, Shi WZ, Liu L, Gong MC, Guo Y, Deng GP, Xu TL, Lin KC. [Practice and Reflection on the Battle against COVID-19 by Guangdong Medical Aid Team in the city of Honghu]. Zhonghua Yi Xue Za Zhi 2020; 100:E018. [PMID: 32157848 DOI: 10.3760/cma.j.cn112137-20200228-00496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Affiliation(s)
- H Zhu
- Nanfang Hospital, South Medical University,Guangzhou 510151 China
| | - W Z Shi
- Digital China Health Technologies Co.ltd, Beijng 100085 China
| | - L Liu
- Nanfang Hospital, South Medical University,Guangzhou 510151 China
| | - M C Gong
- Digital China Health Technologies Co.ltd, Beijng 100085 China
| | - Y Guo
- Nanfang Hospital, South Medical University,Guangzhou 510151 China
| | - G P Deng
- Nanfang Hospital, South Medical University,Guangzhou 510151 China
| | - T L Xu
- Nanfang Hospital, South Medical University,Guangzhou 510151 China
| | - K C Lin
- Nanfang Hospital, South Medical University,Guangzhou 510151 China
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Lin KC, Muthukumar S, Prasad S. Flex-GO (Flexible graphene oxide) sensor for electrochemical monitoring lactate in low-volume passive perspired human sweat. Talanta 2020; 214:120810. [PMID: 32278429 DOI: 10.1016/j.talanta.2020.120810] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 01/30/2020] [Accepted: 02/05/2020] [Indexed: 12/24/2022]
Abstract
In this work, a low volume, sweat lactate sensor functioning on passively expressed eccrine sweat was designed, fabricated and tested in human sweat and its performance was benchmarked against a standard reference; Lactate Plus meter. This novel sensor comprises of graphene oxide (GO) nanosheets integrated into a nanoporous flexible electrode system for low-volume (1-5 μL) ultrasensitive impedance based detection of lactate using non-faradaic electron-ionic charge transfer. Lactate oxidase (LOD) enzyme was immobilized on the surface of GO nanosheets towards developing an affinity biosensor specific to the physiological relevant range (4-80 mM) of lactate in perspired human sweat. Sensing was achieved by measuring impedance changes specific to lactate binding along the GO nanosheet interface using electrochemical impedance spectroscopy. The sensor demonstrated a dynamic range from 1 to 100 mM spiked in synthetic and human sweat with a limit of detection of 1 mM. A specificity study conducted using cortisol expressed in sweat revealed a negative response to the lactate oxidase. Continuous lactate sensing studies were performed during which the sensor was responsive to concentrations of lactate up to 138.6 mM. Correlation of the sensor response with actual lactate concentration (1.3-113.4 mM) was found to be 0.955.
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Affiliation(s)
- Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA
| | | | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA.
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Lin KC, Kinnamon D, Sankhala D, Muthukumar S, Prasad S. AWARE: A Wearable Awareness with Real-time Exposure, for monitoring alcohol consumption impact through ethyl glucuronide detection. Alcohol 2019; 81:93-99. [PMID: 30366035 DOI: 10.1016/j.alcohol.2018.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 09/14/2018] [Accepted: 10/17/2018] [Indexed: 12/31/2022]
Abstract
Here we demonstrate for the first time a dynamic monitoring of the ethanol metabolite ethyl glucuronide (EtG) for a more robust evaluation of alcohol consumption, compared to conventional methods. A wearable biosensor device capable of reporting EtG levels in sweat continuously via low power impedance spectroscopy is reported. The custom hardware was compared against a conventional benchtop potentiostat, and demonstrated comparable results in the application of EtG detection in low volume sweat. The device successfully differentiated three distinct EtG concentrations correlating to simulated drinking scenarios estimated to be 1, 2, and 3 standard U.S. drinks consumed over a duration of 60 min, with p < 0.0001. This device has the potential to enable moderate drinkers to engage in guided decision-making, based on objective data, to address the needs of alcohol-sensitive populations. The device also will serve as a tool for researchers to better understand and characterize the relationship between sweat EtG and consumed alcohol.
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Affiliation(s)
- Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Rd., Richardson, TX 75080, United States
| | - David Kinnamon
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Rd., Richardson, TX 75080, United States
| | - Devangsingh Sankhala
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Rd., Richardson, TX 75080, United States
| | | | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Rd., Richardson, TX 75080, United States.
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Abstract
Misclassification of an acute disease condition as chronic and vice versa by electrochemical sweat biomarker sensors can cause significant psychological, emotional, and financial stress among patients. To achieve higher accuracy in distinguishing between a chronic condition and an acute condition, there is a need to establish a reference biomarker to index the actual chronic disease biomarker of interest by combinatorial sensing. This work provides the first technological proof of leveraging the chloride ion content in sweat for a combinatorial sweat biomarker benchmarking scheme. In this scheme, the sweat chloride ion has been demonstrated as the reference/indexing biomarker, while sweat cortisol has been studied as the disease biomarker of interest. Label-free affinity biosensing is achieved by using a two-electrode electrochemical system on a flexible substrate suitable for wearable applications. The electrochemical stability of the fabricated electrodes for biosensing applications was studied by open-circuit potential measurements. Attenuated total reflectance-Fourier transform infrared spectroscopy spectra validate the crosslinker-antibody binding chemistry. Concentration-dependent analyte-capture probe binding induces a modulation in the electrical properties (charge transfer resistance and double-layer capacitance) at the electrode-sweat buffer interface, which are transduced by nonfaradaic electrochemical impedance spectroscopy (EIS). Calibration dose responses for the sensor for cortisol (5-200 ng/mL) and chloride (10-100 mM) detection were evaluated in synthetic (pH 6) and pooled human sweat (R2 > 0.95). The variation in the cortisol sensor response due to fluctuations in sweat chloride levels and the significance of reporting normalized biomarker levels were demonstrated to further emphasize the need for biomarker benchmarking in electrochemical sensors.
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Affiliation(s)
- Antra Ganguly
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA
| | - Paul Rice
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA
| | - Kai-Chun Lin
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA
| | | | - Shalini Prasad
- Biomedical Microdevices and Nanotechnology Laboratory, Department of Bioengineering, University of Texas at Dallas, Richardson, TX, USA
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Lin HY, Lee YJ, Lin KC, Tsai CC. Clipping of spinal arteriovenous fistula of the filum terminale under intraoperative angiography guidance. Formos J Surg 2019. [DOI: 10.4103/fjs.fjs_36_19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Tsai CC, Wan D, Lin HY, Lin KC. Simultaneous or staged operation? Timing of cranioplasty and ventriculoperitoneal shunt after decompressive craniectomy. Formos J Surg 2019. [DOI: 10.4103/fjs.fjs_18_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Lin KC, Jagannath B, Muthukumar S, Prasad S. Sub-picomolar label-free detection of thrombin using electrochemical impedance spectroscopy of aptamer-functionalized MoS 2. Analyst 2018. [PMID: 28650005 DOI: 10.1039/c7an00548b] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
An ultrasensitive aptasensor for the label free non-faradaic detection of thrombin has been demonstrated on molybdenum disulphide (MoS2) nanosheets. These nanosheets were physiochemically immobilized onto a silicon micro-electrode platform. Thrombin detection was achieved through the charge modulation of the electrical double layer due to the specific and dose dependent binding of thrombin to the surface of thiol terminated ssDNA aptamer functionalized MoS2 nanosheets. Electrical double layer charge modulation associated with thrombin binding was characterized using electrochemical impedance spectroscopy. Dynamic light scattering was also used to confirm the dose dependent behavior. ATR-FTIR spectroscopy and XPS analysis were independently used to validate the functionalization of the ssDNA aptamer onto MoS2 nanosheets. ssDNA aptamer functionalized molybdenum disulfide (MoS2) for selective and specific capture of thrombin was demonstrated both in phosphate buffered saline (PBS) and human serum. The optimized immunoassay enabled the detection of thrombin ranging from 267 fM to 267 pM in phosphate buffer. The limit of detection of 53 pM and the linear dynamic range of detection of thrombin ranged from 53 to 854 pM in human serum. The rapid response time for the electrochemical impedance spectroscopy signal makes it an attractive option for the real-time detection of thrombin based point-of-care diagnostic devices.
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Affiliation(s)
- Kai-Chun Lin
- Department of Bioengineering, University of Texas, Dallas, Richardson, TX 75080, USA.
| | - Badrinath Jagannath
- Department of Bioengineering, University of Texas, Dallas, Richardson, TX 75080, USA.
| | | | - Shalini Prasad
- Department of Bioengineering, University of Texas, Dallas, Richardson, TX 75080, USA.
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Kinnamon D, Ghanta R, Lin KC, Muthukumar S, Prasad S. Portable biosensor for monitoring cortisol in low-volume perspired human sweat. Sci Rep 2017; 7:13312. [PMID: 29042582 PMCID: PMC5645384 DOI: 10.1038/s41598-017-13684-7] [Citation(s) in RCA: 105] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 09/27/2017] [Indexed: 12/26/2022] Open
Abstract
A non-faradaic label-free cortisol biosensor was demonstrated using MoS2 nanosheets integrated into a nanoporous flexible electrode system. Low volume (1–5 μL) sensing was achieved through use of a novel sensor stack design comprised of vertically aligned metal electrodes confining semi-conductive MoS2 nanosheets. The MoS2 nanosheets were surface functionalized with cortisol antibodies towards developing an affinity biosensor specific to the physiological relevant range of cortisol (8.16 to 141.7 ng/mL) in perspired human sweat. Sensing was achieved by measuring impedance changes associated with cortisol binding along the MoS2 nanosheet interface using electrochemical impedance spectroscopy. The sensor demonstrated a dynamic range from 1–500 ng/mL with a limit of detection of 1 ng/mL. A specificity study was conducted using a metabolite expressed in human sweat, Ethyl Glucuronide. Continuous dosing studies were performed during which the sensor was able to discriminate between four cortisol concentration ranges (0.5, 5, 50, 500 ng/mL) for a 3+ hour duration. Translatability of the sensor was shown with a portable form factor device, demonstrating a comparable dynamic range and limit of detection for the sensor. The device demonstrated a R2 correlation value of 0.998 when comparing measurements to the reported impedance values of the benchtop instrumentation.
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Affiliation(s)
- David Kinnamon
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA
| | - Ramesh Ghanta
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA
| | - Kai-Chun Lin
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA
| | | | - Shalini Prasad
- Department of Bioengineering, University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA.
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Lin KC, Twu MJ, Deng RH, Liu CH. The Impacts of Contact Etch Stop Layer Thickness and Gate Height on Channel Stress in Strained N-Metal Oxide Semiconductor Field Effect Transistors. J Nanosci Nanotechnol 2015; 15:2673-2679. [PMID: 26353480 DOI: 10.1166/jnn.2015.9834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The stress induced by strain in the channel of metal oxide semiconductor field effect transistors (MOSFET) is an effective method to boost the device performance. The geometric dimensions of spacer, gate height, and the contact etch stop layer (CESL) are important factors among the feasible booster. This study utilized the mismatch of the thermal expansion coefficients of stressors to simulate the process-induced stress in the N-MOSFET. Different temperatures are applied to different region of the device to generate the required strain. The analysis was performed by well-developed finite element package. The composite spacers with variant width of inserted silicon nitride (SiO2/SiN/SiO2, ONO) were proposed and their impacts on channel stress were compared. Two aspects of the impacts of those factors on the channel stress in the longitudinal direction for N-MOSFET with variant channel length were investigated. Firstly, the channel stresses of device without CESL for different gate heights were studied. Secondly, with stress applied to CESL and ONO spacers, the induced stresses in the channel were analyzed for long/short gate length. Two conclusions were drawn from the results of simulation. The N-MOSFET device without CESL shows that the stressed spacer alone generates compressive stress and the magnitude increases along with higher gate height. The channel stress becomes tensile for device with CESL and increases when the thickness of CESL and the height of gate increase, especially for device with shorter gate length. The gate height plays more significant role in inducing channel stress compared with the thickness of CESL. The channel stress can be used to quantify the mobility of electron/hole for strained MOSFET device. Therefore, with the guideline disclosed in this study, better device performance can be expected for N-MOSFET.
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Chin HY, Lin KC, Chiang CH, Wang CJ. Single uroflow study as a tool in predicting the possibility of abnormal voiding symptoms after the administration of antimuscarinic agents in treating overactive bladder syndrome. CLIN EXP OBSTET GYN 2015; 42:152-155. [PMID: 26054108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE OF STUDY The aim of this study was to evaluate the efficacy of uroflowmetry in predicting the possibility of abnormal voiding symptoms following antimuscarinic treatment for overactive bladder syndrome (OAB) in Taiwanese women. MATERIALS AND METHODS A retrospective study was conducted on women with OAB. Forty-five women with abnormal voiding patterns shown by urodynamic study comprised the main group and 38 women with normal voiding patterns comprised the control group. All patients were prescribed two mg tolterodine once daily for one week. Follow-up on complaints of abnormal voiding symptoms was done one week later. RESULTS One woman in control group and 12 women in main group complained of abnormal voiding symptoms. There was a significant difference in the occurrence of abnormal voiding symptoms after antimuscarinic administration between main study group and control group (26.7 % vs 2.6 %, p = 0.02). CONCLUSIOn: Uroflowmetry is a non-invasive and simple tool to predict the occurrence of abnormal voiding symptoms after antimuscarinic use.
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Ramakrishnan S, Goryll M, Lin KC, Dey SK, Ramakrishna B. Nano-Bilayer Lipid Membranes Hosted on Biogenic Nanoporous Substrates. Biophys J 2014. [DOI: 10.1016/j.bpj.2013.11.599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Huber B, Drewes JE, Lin KC, König R, Müller E. Revealing biogenic sulfuric acid corrosion in sludge digesters: detection of sulfur-oxidizing bacteria within full-scale digesters. Water Sci Technol 2014; 70:1405-1411. [PMID: 25353947 DOI: 10.2166/wst.2014.371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Biogenic sulfuric acid corrosion (BSA) is a costly problem affecting both sewerage infrastructure and sludge handling facilities such as digesters. The aim of this study was to verify BSA in full-scale digesters by identifying the microorganisms involved in the concrete corrosion process, that is, sulfate-reducing (SRB) and sulfur-oxidizing bacteria (SOB). To investigate the SRB and SOB communities, digester sludge and biofilm samples were collected. SRB diversity within digester sludge was studied by applying polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) targeting the dsrB-gene (dissimilatory sulfite reductase beta subunit). To reveal SOB diversity, cultivation dependent and independent techniques were applied. The SRB diversity studies revealed different uncultured SRB, confirming SRB activity and H2S production. Comparable DGGE profiles were obtained from the different sludges, demonstrating the presence of similar SRB species. By cultivation, three pure SOB strains from the digester headspace were obtained including Acidithiobacillus thiooxidans, Thiomonas intermedia and Thiomonas perometabolis. These organisms were also detected with PCR-DGGE in addition to two new SOB: Thiobacillus thioparus and Paracoccus solventivorans. The SRB and SOB responsible for BSA were identified within five different digesters, demonstrating that BSA is a problem occurring not only in sewer systems but also in sludge digesters. In addition, the presence of different SOB species was successfully associated with the progression of microbial corrosion.
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Affiliation(s)
- B Huber
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail:
| | - J E Drewes
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail:
| | - K C Lin
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail:
| | - R König
- Weber-Ingenieure GmbH, Bauschlotter Straße 62, 75177 Pforzheim, Germany
| | - E Müller
- Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail:
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Chao MS, Tornero J, Lin KC, Stolte S, González Ureña A. Decoherence cross-section in NO + Ar collisions: experimental results and a simple model. J Phys Chem A 2013; 117:8119-25. [PMID: 23556513 DOI: 10.1021/jp401005v] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Quantum decoherence can be viewed as the mechanism responsible for the quantum-to-classical transition as the initially prepared quantum state interacts with its environment in an irreversible manner. One of the most common mechanisms responsible for the macroscopically observed decoherence involves collisions of an atom or molecule, initially prepared in a coherent superposition of states, with gas particles. In this work, a coherent superposition of quantum internal states of NO molecules is prepared by the interaction between the molecule with both a static and a radiofrequency electric field. Subsequently, NO + Ar collision decoherence experiments are investigated by measuring the loss of coherence as a function of the number of collisions. Data analysis using a model based on the interaction potential of the collisional partners allowed to unravel the molecular mechanism responsible for the loss of coherence in the prepared NO quantum superposition of internal states. The relevance of the present work relies on several aspects. On the one hand, the use of radio-waves introduces a new way for the production of coherent beams. On the other hand, the employed methodology could be useful in investigating the Stereodynamics of chemical reactions with coherent reagents.
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Affiliation(s)
- M-S Chao
- Unidad de Láseres y Haces Moleculares Instituto Pluridisciplinar, Universidad Complutense de Madrid, Madrid, Spain
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Chen YC, Dong GH, Lin KC, Lee YL. Gender difference of childhood overweight and obesity in predicting the risk of incident asthma: a systematic review and meta-analysis. Obes Rev 2013; 14:222-31. [PMID: 23145849 DOI: 10.1111/j.1467-789x.2012.01055.x] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Revised: 08/29/2012] [Accepted: 09/23/2012] [Indexed: 11/28/2022]
Abstract
The aims of our meta-analysis were (i) to quantify the predictability of childhood overweight and obesity on the risk of incident asthma; and (ii) to evaluate the gender difference on this relationship. The selection criteria included prospective cohort paediatric studies which use age- and sex-specific body mass index (BMI) as a measure of childhood overweight and the primary outcome of incident asthma. A total of 1,027 studies were initially identified through online database searches, and finally 6 studies met the inclusion criteria. The combined result of reported relative risk from the 6 included studies revealed that overweight children conferred increased risks of incident asthma as compared with non-overweight children (relative risk, 1.19; 95% confidence interval [CI], 1.03-1.37). The relationship was further elevated for obesity vs. non-obesity (relative risk, 2.02; 95% CI, 1.16-3.50). A dose-responsiveness of elevated BMI on asthma incidence was observed (P for trend, 0.004). Obese boys had a significantly larger effect than obese girls (relative risk, boys: 2.47; 95% CI, 1.57-3.87; girls: 1.25; 95% CI, 0.51-3.03), with significant dose-dependent effect. Proposed mechanisms of gender difference could be through pulmonary mechanics, sleep disordered breathing and leptin. Further research might be needed to better understand the exact mechanism of gender difference on the obesity-asthma relationship.
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Affiliation(s)
- Y C Chen
- Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan
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Goryll M, Lin KC, Wang X, Ramakrishnan S, Gosse M, Dey SK, Ramakrishna B. Integration of Biogenic Nanopore Membranes on Prefabricated Fluidic Support Substrates. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.2886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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Chin HY, Lin KC, Chiang CH, Wang CJ. Combination of baclofen and antimuscarinics to reduce voiding difficulty in treating women with overactive bladders. CLIN EXP OBSTET GYN 2012; 39:171-174. [PMID: 22905457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
PURPOSE OF STUDY To evaluate the efficacy of baclofen in combination with antimuscarinics to treat women with an overactive bladder (OAB) with abnormal voiding patterns. METHODS An action research and chart review was conducted in 245 OAB women. Women were prescribed tolterodine or oxybutynin with or without baclofen after urodynamics. The complaint of voiding difficulty was followed up one week later. RESULTS There was a significant difference in the occurrence of voiding difficulty after antimuscarinic administration in OAB women with abnormal voiding patterns compared with normal patterns (18% vs 4.9%, respectively; p = 0.013). The clinical difference of voiding difficulty after treating with antimuscarinics between both voiding patterns disappeared after adding baclofen (abnormal voiding pattern vs normal pattern; 11.1% vs. 5.6%, respectively; p = 1.000). CONCLUSION Combined use of baclofen and antimuscarinic agents could reduce voiding difficulty in treating women with overactive bladders with abnormal voiding patterns.
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Affiliation(s)
- H Y Chin
- Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital at Keelung, Keelung, Taiwan
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Lo HM, Chiang CF, Tsao HC, Pai TY, Liu MH, Kurniawan TA, Chao KP, Liou CT, Lin KC, Chang CY, Wang SC, Banks CJ, Lin CY, Liu WF, Chen PH, Chen CK, Chiu HY, Wu HY, Chao TW, Chen YR, Liou DW, Lo FC. Effects of spiked metals on the MSW anaerobic digestion. Waste Manag Res 2012; 30:32-48. [PMID: 20880938 DOI: 10.1177/0734242x10383079] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
This study aimed to investigate the effects of eight metals on the anaerobic digestion of the organic fraction of municipal solid waste (OFMSW) in bioreactors. Anaerobic bioreactors containing 200 mL MSW mixed completely with 200 m L sludge seeding. Ca and K (0, 1000, 2000 and 6,000 mg L(-1)) and Cr, Ni, Zn, Co, Mo and W (0, 5, 50 and 100 mg L(-1)) of various dose were added to anaerobic bioreactors to examine their anaerobic digestion performance. Results showed that except K and Zn, Ca (~728 to ~1,461 mg L(-1)), Cr (~0.0022 to ~0.0212 mg L(-1)), Ni (~0.801 to ~5.362 mg L(-1)), Co (~0.148 to ~0.580 mg L(-1)), Mo (~0.044 to ~52.94 mg L(-1)) and W (~0.658 to ~40.39 mg L(-1)) had the potential to enhance the biogas production. On the other hand, except Mo and W, inhibitory concentrations IC(50) of Ca, K, Cr, Ni, Zn and Co were found to be ~3252, ~2097, ~0.124, ~7.239, ~0.482, ~8.625 mg L(-1), respectively. Eight spiked metals showed that they were adsorbed by MSW to a different extent resulting in different liquid metals levels and potential stimulation and inhibition on MSW anaerobic digestion. These results were discussed and compared to results from literature.
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Affiliation(s)
- H M Lo
- Department of Environmental Engineering and anagement, Chaoyang University of Technology, Wufong Township, Taichung County, Taiwan, ROC.
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Masek-Hammerman K, Miller AD, Lin KC, MacKey J, Weissenböck H, Gierbolini L, Burgos A, Perez H, Mansfield KG. Epizootic myocarditis associated with encephalomyocarditis virus in a group of rhesus macaques (Macaca mulatta). Vet Pathol 2011; 49:386-92. [PMID: 21653204 DOI: 10.1177/0300985811409254] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Six cases of fatal myocarditis associated with encephalomyocarditis virus occurred over a 14-month period in a group of outdoor-housed juvenile rhesus macaques. All animals were younger than 3 years of age and died or were euthanized following acute onset of dyspnea or pulmonary effusion (3 of 6) or were found dead without premonitory signs (3 of 6). Gross findings included pulmonary congestion (6 of 6), variable degrees of pleural effusion (4 of 6), multifocal pale tan foci throughout the myocardium (3 of 6), hepatomegaly and hepatic congestion (3 of 6), and pericardial effusion (1 of 6). Histologically, affected myocardium was infiltrated multifocally by lymphoplasmacytic and histiocytic inflammation admixed with necrotic and degenerate myofibers and infrequent mineralization (6 of 6). Pulmonary edema was present in all animals. Encephalomyocarditis virus was confirmed in 6 of 6 hearts by immunohistochemistry, and virus was isolated from one case by polymerase chain reaction. Sequencing of virus isolated from 1 affected animal indicated infection with a novel encephalomyocarditis virus. Encephalomyocarditis virus should be considered as a differential etiology in outbreaks of myocarditis and pulmonary edema in juvenile primates.
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Affiliation(s)
- K Masek-Hammerman
- New England Primate Research Center, Harvard Medical School, Southborough, MA 01772, USA
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Lo HM, Kurniawan TA, Sillanpää MET, Pai TY, Chiang CF, Chao KP, Liu MH, Chuang SH, Banks CJ, Wang SC, Lin KC, Lin CY, Liu WF, Cheng PH, Chen CK, Chiu HY, Wu HY. Modeling biogas production from organic fraction of MSW co-digested with MSWI ashes in anaerobic bioreactors. Bioresour Technol 2010; 101:6329-6335. [PMID: 20400299 DOI: 10.1016/j.biortech.2010.03.048] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 03/08/2010] [Accepted: 03/11/2010] [Indexed: 05/29/2023]
Abstract
This study aims at investigating the effects of MSW incinerator fly ash (FA) and bottom ash (BA) on the anaerobic co-digestion of OFMSW with FA or BA. It also simulates the biogas production from various dosed and control bioreactors. Results showed that suitable ashes addition (FA/MSW 10 and 20 g L(-1) and BA/MSW 100 g L(-1)) could improve the MSW anaerobic digestion and enhance the biogas production rates. FA/MSW 20 g L(-1) bioreactor had the higher biogas production and rate implying the potential option for MSW anaerobic co-digestion. Modeling studies showed that exponential plot simulated better for FA/MSW 10 g L(-1) and control bioreactors while Gaussian plot was applicable for FA/MSW 20 g L(-1) one. Linear and exponential plot of descending limb both simulated better for BA/MSW 100 g L(-1) bioreactor. Modified Gompertz plot showed higher correlation of biogas accumulation than exponential rise to maximum plot for all bioreactors.
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Affiliation(s)
- H M Lo
- Department of Environmental Engineering and Management, Chaoyang University of Technology, Taichung County, Taiwan, ROC.
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Abstract
Small intestinal adenocarcinomas are uncommon neoplasms that are rarely reported in nonhuman primates. These neoplasms are also rare in humans, although they are thought to share a similar pathogenesis with the more common colorectal carcinoma. Herein the authors report the clinical, histologic, immunohistochemical, and molecular characteristics of small intestinal adenocarcinoma in 10 common marmosets (Callithrix jacchus). Retrospective analysis of necropsy records revealed small intestinal carcinoma to be the most common neoplastic cause of morbidity and mortality in aged common marmosets. The average age of affected animals was 6.6 years old, and there was no sex predilection. Nine of 10 (90%) tumors arose within the proximal small intestine near the interface with the duodenum. All cases were characterized by disorganization, loss of polarity, and proliferation of neoplastic epithelial cells along the crypt to midvillous interface. Two of 10 (20%) were defined as carcinoma in situ. Eight of 10 (80%) had some degree of invasion, with lymphatic invasion and lymph node metastasis present in 6 of 10 (60%) animals. Immunohistochemically, 10 of 10 (100%) expressed cytokeratin; 7 of 9 (77%) expressed E-cadherin; and 8 of 9 (88%) expressed beta-catenin. The expression of E-cadherin and beta-catenin was decreased in the cell membrane and increased in the cytoplasm. No Helicobacter-like bacteria were observed via silver stain, and callitrichine herpesvirus 3 was detected by polymerase chain reaction with equal frequency from neoplastic and nonneoplastic intestinal sections. The tumors described in this population illustrate comparable features to human cases of small intestine carcinoma and may serve as a potential animal model for small intestinal carcinomas.
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Affiliation(s)
- A D Miller
- New England Regional Primate Research Center, Harvard Medical School, One Pine Hill Drive, Southborough, MA 01760, USA.
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Lin KC, Kunduru V, Bothara M, Rege K, Prasad S, Ramakrishna BL. Biogenic nanoporous silica-based sensor for enhanced electrochemical detection of cardiovascular biomarkers proteins. Biosens Bioelectron 2010; 25:2336-42. [PMID: 20417087 DOI: 10.1016/j.bios.2010.03.032] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 03/22/2010] [Accepted: 03/24/2010] [Indexed: 11/25/2022]
Abstract
The goal of our research is to demonstrate the feasibility of employing biogenic nanoporous silica as a key component in developing a biosensor platform for rapid label-free electrochemical detection of cardiovascular biomarkers from pure and commercial human serum samples with high sensitivity and selectivity. The biosensor platform consists of a silicon chip with an array of gold electrodes forming multiple sensor sites and works on the principle of electrochemical impedance spectroscopy. Each sensor site is overlaid with a biogenic nanoporous silica membrane that forms a high density of nanowells on top of each electrode. When specific protein biomarkers: C-reactive protein (CRP) and myeloperoxidase (MPO) from a test sample bind to antibodies conjugated to the surface of the gold surface at the base of each nanowell, a perturbation of electrical double layer occurs resulting in a change in the impedance. The performance of the biogenic silica membrane biosensor was tested in comparison with nanoporous alumina membrane-based biosensor and plain metallic thin film biosensor. Significant enhancement in the sensitivity and selectivity was achieved with the biogenic silica biosensor, in comparison to the other two, for detecting the two protein biomarkers from both pure and commercial human serum samples. The sensitivity of the biogenic silica biosensor is approximately 1 pg/ml and the linear dose response is observed over a large dynamic range from 1 pg/ml to 1 microg/ml. Based on its performance metrics, the biogenic silica biosensor has excellent potential for development as a point of care handheld electronic biosensor device for detection of protein biomarkers from clinical samples.
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Affiliation(s)
- Kai-Chun Lin
- School of Mechanical, Aerospace, Chemical, and Materials Engineering, Arizona State University, Tempe, AZ 85287-6106, USA
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Lin YF, Wu ZY, Lin KC, Chen CC, Jian WB, Chen FR, Kai JJ. Nanocontact resistance and structural disorder induced resistivity variation in metallic metal-oxide nanowires. Nanotechnology 2009; 20:455401. [PMID: 19822926 DOI: 10.1088/0957-4484/20/45/455401] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Several systems of metallic metal-oxide nanowires (NWs), including pure RuO2 and as-implanted and annealed Ru(0.98)Cu(0.02)O2 and Ru(0.93)Cu(0.07)O2 NWs, have been employed in two-probe electrical characterizations by using a transmission electron microscope-scanning tunneling microscope technique with a gold tip. Thermal, mechanical, and electron beam exposing treatments are consecutively applied to reduce the electrical contact resistance, generated from the interface between the NW and the gold tip, so as to evaluate the intrinsic NW resistance. It is found that the residual contact resistance cannot be entirely removed. For each system of metallic metal-oxide NWs, several tens of NWs are applied to electrical characterizations and the total resistances unveil a linear dependence on the ratio of the length to the area of the NWs. As a result, the average resistivity and the contact resistance of the metallic metal-oxide NWs could be evaluated at room temperatures. The average resistivities of pure RuO2 NWs agree well with the results obtained from standard two- and four-probe electrical-transport measurements. In addition, the as-implanted Cu-RuO2 NWs reveal disordered crystalline structures in high-resolution TEM images and give higher resistivities in comparison with that of pure RuO2 NWs. The residual contact resistances of all kinds of metallic metal-oxide NWs unveil, more surprisingly, an approximation value of several kilohms, even though the average resistivities of these NWs change by more than one order of magnitude. It is argued that the ductile gold tip makes one or more soft contacts on the stiff metal-oxide NWs with nanometer roughness and the nanocontacts on the NWs contribute to the electrical contact resistance.
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Affiliation(s)
- Y F Lin
- Department of Electrophysics, National Chiao Tung University, Hsinchu 30010, Taiwan
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Chou JW, Lin KC, Tang YT, Hsueh FK, Lee YJ, Luo CW, Chen YN, Yuan CT, Shih HC, Fan WC, Lin MC, Chou WC, Chuu DS. Fluorescence signals of quantum dots influenced by spatially controlled array structures. Nanotechnology 2009; 20:415201. [PMID: 19755732 DOI: 10.1088/0957-4484/20/41/415201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Fluorescence signals of quantum dots (QDs) influenced by different array structures of gold-coated silicon nanorods (SiNRs) were investigated via experimental observations and two-dimensional (2D) finite element method (FEM) simulations. On the densest gold-coated SiNRs array structure, the highest QD fluorescence quenching rates were observed and on the sparsest array structure, the highest QD fluorescence enhancement rates were observed. By developing a new technique which obtains the optical image of the array structures without losing information about the QD locations, we were able to further investigate how the QD fluorescence is influenced by spatially controlled array structures.
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Affiliation(s)
- J W Chou
- Department of Electrophysics, National Chiao Tung University, Hsinchu 30050, Taiwan
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Chen WS, Chen CH, Lin KC, Tsai CY, Liao HT, Wang HB, Chen YK, Yang AH, Chen TC, Chou CT. Immunohistological features of hip synovitis in ankylosing spondylitis with advanced hip involvement. Scand J Rheumatol 2009; 38:154-5. [PMID: 19165649 DOI: 10.1080/03009740802409504] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Lo HM, Liu MH, Pai TY, Liu WF, Lin CY, Wang SC, Banks CJ, Hung CH, Chiang CF, Lin KC, Chen PH, Chen JK, Chiu HY, Su MH, Kurniawan TA, Wu KC, Hsieh CY, Hsu HS. Biostabilization assessment of MSW co-disposed with MSWI fly ash in anaerobic bioreactors. J Hazard Mater 2009; 162:1233-1242. [PMID: 18653282 DOI: 10.1016/j.jhazmat.2008.06.028] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2007] [Revised: 05/03/2008] [Accepted: 06/09/2008] [Indexed: 05/26/2023]
Abstract
Municipal solid waste incinerator (MSWI) fly ash has been examined for possible use as landfill interim cover. For this aim, three anaerobic bioreactors, 1.2m high and 0.2m in diameter, were used to assess the co-digestion or co-disposal performance of MSW and MSWI fly ash. Two bioreactors contained ratios of 10 and 20 g fly ash per liter of MSW (or 0.2 and 0.4 g g(-1) VS, that is, 0.2 and 0.4 g fly ash per gram volatile solids (VS) of MSW). The remaining bioreactor was used as control, without fly ash addition. The results showed that gas production rate was enhanced by the appropriate addition of MSWI fly ash, with a rate of approximately 6.5l day(-1)kg(-1)VS at peak production in the ash-added bioreactors, compared to approximately 4l day(-1)kg(-1)VS in control. Conductivity, alkali metals and VS in leachate were higher in the fly ash-added bioreactors compared to control. The results show that MSW decomposition was maintained throughout at near-neutral pH and might be improved by release of alkali and trace metals from fly ash. Heavy metals exerted no inhibitory effect on MSW digestion in all three bioreactors. These phenomena indicate that proper amounts of MSWI fly ash, co-disposed or co-digested with MSW, could facilitate bacterial activity, digestion efficiency and gas production rates.
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Affiliation(s)
- H M Lo
- Department of Environmental Engineering and Management, Chaoyang University of Technology, 168, Jifong East Road, Wufong, Taichung County, Taiwan.
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Lo HM, Lin KC, Liu MH, Pai TZ, Lin CY, Liu WF, Fang GC, Lu C, Chiang CF, Wang SC, Chen PH, Chen JK, Chiu HY, Wu KC. Solubility of heavy metals added to MSW. J Hazard Mater 2009; 161:294-299. [PMID: 18457918 DOI: 10.1016/j.jhazmat.2008.03.119] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2007] [Revised: 01/27/2008] [Accepted: 03/20/2008] [Indexed: 05/26/2023]
Abstract
This paper aims to investigate the six heavy metal levels (Cd, Cr, Cu, Pb, Ni and Zn) in municipal solid waste (MSW) at different pHs. It intends to provide the baseline information of metals solubility in MSW co-disposed or co-digested with MSW incinerator ashes in landfill or anaerobic bioreactors or heavy metals contaminated in anaerobic digesters. One milliliter (equal to 1mg) of each metal was added to the 100ml MSW and the batch reactor test was carried out. The results showed that higher HNO3 and NaOH were consumed at extreme pH of 1 and 13 compared to those from pH 2 to 11 due to the comparably higher buffer capacity. Pb was found to have the least soluble level, highest metal adsorption (%) and highest partitioning Kd (lg(-1)) between pH 3 and 12. In contrast, Ni showed the highest soluble level, lowest metal adsorption (%) and lowest Kd (lg(-1)) between pH 4 and 12. Except Ni and Cr, other four metals seemed to show the amphibious properties as comparative higher solubility was found in the acidic and basic conditions.
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Affiliation(s)
- H M Lo
- Department of Environmental Engineering and Management, Chaoyang University of Technology, 168 Gifong E. Road, Wufong, Taichung County 41349, Taiwan, ROC.
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Lin CH, Lin KC, Tang TB, Pai WW. Anomalous surface diffusion of C60 and anisotropic growth of nano islands on Ni(111). J Nanosci Nanotechnol 2008; 8:602-7. [PMID: 18464377 DOI: 10.1166/jnn.2008.d224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The migration behavior of C60 on Ni(111) has been inferred from its growth morphology at various substrate temperatures, as observed with scanning tunneling microscopy. The number density of islands increased and their average sizes decreased anomalously in the temperature range of approximately 573 K to approximately 973 K. This trend contradicts the prediction in conventional nucleation theory. At low and high temperatures, C60 commence nucleation on both sides of surface steps in a "bi-directional step flow" mode. However, anisotropy occurs within an intermediate temperature range, in which C60 nucleate predominantly at upper step edges. Surprisingly, in-situ growth measurements at this intermediate temperature range revealed that C60 actually start nucleating from lower step edges, with concomitant formation of Ni terraces underneath. These anomalous thermal dependence of diffusivity and the peculiar growth morphology of C60 on Ni(111) are attributed to C60-induced reconstruction of Ni(111) at higher temperature.
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Affiliation(s)
- C H Lin
- Center for Condensed Matter Sciences, National Taiwan University, Taipei 106, Taiwan, RO China
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Abstract
Nocardia, Rhodococcus and Streptomyces, all members of the actinomycetes family, are Gram-positive eubacteria with high G+C content and able to form mycelium. We report here a newly identified plasmid pXT107 of Nocardia sp. 107, one of the smallest circular plasmids found in Nocardia. The complete nucleotide sequence of pXT107 consisted of 4335 bp with 65% G+C content, and encoded one replication extragenic palindromic (Rep) and six hypothetical proteins. The Rep, double-strand origin and single-strand origin of pXT107 resembled those of typical rolling-circle-replication plasmids, such as pNI100 of Nocardia, pRE8424 of Rhodococcus and pIJ101 of Streptomyces. The Escherichia coli-Nocardia shuttle plasmid pHAQ22, containing the rep gene of pXT107, is able to propagate in Nocardia but not in Streptomyces.
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Affiliation(s)
- Hai-Yang Xia
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
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Chen HA, Lin KC, Chen CH, Liao HT, Wang HP, Chang HN, Tsai CY, Chou CT. The effect of etanercept on anti-cyclic citrullinated peptide antibodies and rheumatoid factor in patients with rheumatoid arthritis. Ann Rheum Dis 2005; 65:35-9. [PMID: 15975966 PMCID: PMC1797988 DOI: 10.1136/ard.2005.038851] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To evaluate the changes in anti-cyclic citrullinated peptide antibodies (anti-CCP) and rheumatoid factor (RF) following etanercept treatment in patients with rheumatoid arthritis. METHODS The study included 90 patients with rheumatoid arthritis who failed treatment with disease modifying antirheumatic drugs (DMARDs). All patients were allowed to continue treatment with DMARDs; 52 of them received etanercept as a twice weekly 25 mg subcutaneous injection for three months, and the others did not. Serum samples were collected at baseline and one month intervals during the treatment course. The serum levels of anti-CCP and RF were tested by enzyme linked immunosorbent assay and nephelometry, respectively. RESULTS At baseline, 45 of the 52 etanercept treated patients (86.5%) and 32 of the 38 controls (84.2%) were positive for anti-CCP. Tests for RF were positive in 78.9% and 84.2% of patients with or without etanercept treatment, respectively. The serum levels of anti-CCP and RF decreased significantly after a three month etanercept treatment (p = 0.007 and p = 0.006, respectively). The average decrease from baseline calculated for each individual patient in the etanercept treated group was 31.3% for anti-CCP and 36% for RF. The variation in anti-CCP was positively correlated with the variation in disease activity, swollen and tender joint counts, RF, and C reactive protein. CONCLUSIONS Etanercept combined with DMARDs leads to a much greater decrease than DMARDs alone in the serum levels of anti-CCP and RF in rheumatoid arthritis, compatible with a reduction in clinical disease activity.
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Affiliation(s)
- H A Chen
- Section of Allergy-Immunology-Rheumatology, Department of Medicine, Veterans General Hospital-Taipei, Taiwan.
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Chou CT, Lin KC, Wei JCC, Tsai WC, Ho HH, Hwang CM, Cherng JM, Hsu CM, Yu DTY. Study of undifferentiated spondyloarthropathy among first-degree relatives of ankylosing spondylitis probands. Rheumatology (Oxford) 2005; 44:662-5. [PMID: 15741196 DOI: 10.1093/rheumatology/keh577] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE To estimate in a Chinese population the prevalence of undifferentiated spondyloarthropathy (USpA) among first-degree relatives (FDRs) of ankylosing spondylitis (AS) probands, and to compare the clinical features of familial USpA with those of sporadic USpA. METHODS The FDRs of two separate cohorts of consecutive AS probands were evaluated for the prevalence of USpA, using the Modified New York criteria and the European Spondylitis Study Group criteria for AS and SpA, respectively. Sporadic USpA and FDRs of non-SpA rheumatic patient probands served as separate controls. RESULTS Among the 301 FDRs of 102 AS probands, 7.0% were USpA. This was 1000 times higher than the 147 FDRs of 40 non-SpA probands (P = 0.00230). Within the AS families, USpA was less male-dominated than AS (33.3 vs 72.5%) (P = 0.006). The only feature distinguishing familial from sporadic USpA was that the percentages of HLA B27 were 100 and 50%, respectively (P<0.001). CONCLUSION USpA and AS coexist in the same Chinese families, both being predisposed by HLA B27. In these families, a female gender favours the development of USpA rather than AS. A significant subset of sporadic USpA (HLA B27-negative group) has a different genetic predisposition compared with familial USpA.
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Affiliation(s)
- C T Chou
- Division of Allergy-Immunology-Rheumatology, Veterans General Hospital-Taipei, No. 201, Sec. 2, Shipai Road, Beitou Chiu, Taipei, Taiwan 112.
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Chou RH, Lin KC, Lin SC, Cheng JY, Wu CW, Chang WSW. Cost-effective trapezoidal modified Boyden chamber with comparable accuracy to a commercial apparatus. Biotechniques 2004; 37:724-6. [PMID: 15560124 DOI: 10.2144/04375bm01] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Affiliation(s)
- Ruey-Hwang Chou
- National Health Research Institutes, Academia Sinica, Taipei 115, Taiwan
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Abstract
Past reports of the water relations of epiphytes, particularly bromeliads, indicate that tissue osmotic potentials in these tropical and subtropical plants are very high (close to zero) and are similar to values for aquatic plants. This is puzzling because several ecophysiological studies have revealed a high degree of drought stress tolerance in some of these epiphytes. The goal of this study was two-fold: (1) to increase the number of epiphytic taxa sampled for tissue osmotic potentials; and (2) to explain the apparent discrepancy in the significance of the tissue water relations and tolerance of drought stress in epiphytes. Tissue osmotic potentials of 30 species of epiphytic ferns, lycophytes, and orchids were measured in a subtropical rain forest in northeastern Taiwan. Nearly all values were less negative than -1.0 MPa, in line with all previous data for epiphytes. It is argued that such high osmotic potentials, indicative of low solute concentrations, are the result of environmental constraints of the epiphytic habitat on productivity of these plants, and that low rates of photosynthesis and transpiration delay the onset of turgor loss in the tissues of epiphytes such that they appear to be very drought-stress tolerant. Maintenance of photosynthetic activity long into drought periods is ascribed to low rates of transpiration and, hence, delayed tissue desiccation, and hydration of the photosynthetic tissue at the expense of water from the water-storage parenchyma.
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Affiliation(s)
- Craig E Martin
- Department of Ecology & Evolutionary Biology, University of Kansas, Lawrence, KS 66045, USA
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Sharma RC, Thakur SN, Lin KC. A3Pi1u<--X1Sigmag+ laser photoacoustic spectroscopy of Br2 vapor in the extreme red wavelength region 665-720 nm. Spectrochim Acta A Mol Biomol Spectrosc 2004; 60:1889-1893. [PMID: 15248965 DOI: 10.1016/j.saa.2003.08.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2003] [Accepted: 08/01/2003] [Indexed: 05/24/2023]
Abstract
The A3Pi1u<--X1Sigmag+ photoacoustic spectrum of Br2 vapor has been studied and vibronic analysis performed using earlier data available for this system of bands from optical spectroscopy in the region 665-720 nm. The vibronic levels involved in these transitions are 4< or =v'< or =21 and 1< or =v''< or =4. The relative photoacoustic intensities of the vibronic bands have been used in estimating the non-radiative relaxation rate from vibrational levels of A3Pi(1u) state. The non-radiative relaxation is found to be a nonlinear function of the upper state vibrational quantum number. The radiative rate constants for the A3Pi(1u) state vibrational levels have been compared with the corresponding non-radiative constants obtained from present work. Non-radiative decay rate constants for the vibrational levels of A3Pi(1u) state have been experimentally determined for the first time from photoacoustic spectrum of Br2 vapor in the extreme red region.
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Affiliation(s)
- Ramesh C Sharma
- Department of Chemistry, Institute of Atomic and Molecular Sciences, National Taiwan University, Academia Sinica, Taipei 106, Taiwan, ROC.
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Niu KC, Lin KC, Yang CY, Lin MT. Protective effects of alpha-tocopherol and mannitol in both circulatory shock and cerebral ischaemia injury in rat heatstroke. Clin Exp Pharmacol Physiol 2003; 30:745-51. [PMID: 14516413 DOI: 10.1046/j.1440-1681.2003.03905.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
1. There is evidence that hydroxyl radicals are accumulated and oxidative stress is produced in multiple organs, including the brain, of rats with heat stroke. Herein, we investigated the effect on heat stroke-induced circulatory shock and cerebral ischaemic injury of two free radical scavengers, namely mannitol and alpha-tocopherol. 2. Urethane-anaesthetized rats were exposed to heat stress (ambient temperature 42 degrees C) to induce heat stroke. Control rats were exposed to 24 degrees C. Mean arterial pressure and cerebral blood flow after the onset of heat stroke were significantly lower in heat stroke rats than in control rats. However, cerebral free radicals, lipid peroxidation and the neuronal damage score were greater in heat stroke rats compared with control rats. Similarly, plasma cytokines, including tumour necrosis factor-alpha, interleukin (IL)-1beta and IL-6, were significantly higher in heat stroke rats compared with their normothermic controls. 3. Pretreatment with alpha-tocopherol (20 mg/kg, i.v.) or mannitol (10%, i.v.) 30 min before the onset of heat exposure significantly attenuated heat stroke-induced arterial hypotension, cerebral ischaemia and neuronal damage, the increased free radical formation and lipid peroxidation in the brain and the increased plasma levels of cytokines. Pretreatment with alpha-tocopherol or mannitol resulted in a prolongation of survival time in heat stroke. 4. These results demonstrate that although pretreatment with alpha-tocopherol and mannitol does not prevent the heat stroke syndrome entirely, an attenuation of the syndrome is observed.
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Affiliation(s)
- K C Niu
- Department of Hyperbaric Oxygen Therapy, Chi-Mei Medical Center, Yung Kang, Tainan, Taiwan
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Mansfield KG, Lin KC, Xia D, Newman JV, Schauer DB, MacKey J, Lackner AA, Carville A. Enteropathogenic Escherichia coli and ulcerative colitis in cotton-top tamarins (Saguinus oedipus). J Infect Dis 2001; 184:803-7. [PMID: 11517446 DOI: 10.1086/322990] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2001] [Revised: 05/24/2001] [Indexed: 12/24/2022] Open
Abstract
The cotton-top tamarin (CTT; Saguinus oedipus) is an endangered New World primate that develops a highly prevalent idiopathic colitis resembling human ulcerative colitis. This study found that enteropathogenic Escherichia coli (EPEC) caused acute colitis in CTTs, which was associated with ulcerative colitis. EPEC clinical isolates revealed localized adherence patterns by HEp-2 assay and were devoid of Shiga-toxin production. Sequencing of the eae gene (GenBank accession no. AF319597) revealed 99.2% identity to sequences of human isolates (GenBank AF116899) and corresponded to the epsilon intimin gene subtype. Detection of intimin sequences by polymerase chain reaction on primary fecal cultures indicated widespread EPEC infection in the CTT colony. Prospective analysis revealed that animals with fecal cultures positive for intimin sequences had a higher frequency of active colitis (75.0% vs. 27.2%; P<.005, chi(2) test) and higher histological scores of colonic inflammation (0.875 vs. 0.455, respectively; P<.05, Mann-Whitney rank sum test).
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Affiliation(s)
- K G Mansfield
- New England Regional Primate Research Center, Harvard Medical School, Southborough, MA 01772-9012, USA.
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Abstract
The first examples of hetero Diels-Alder reaction of masked o-benzoquinones with nitroso dienophiles leading to novel and highly functionalized heterocycles, which are potential intermediates for nitrogenous natural products are reported.
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Affiliation(s)
- K C Lin
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 300
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