Article
Endocrinology & Metabolism
Nizar I. Mourad, Daela Xhema, Pierre Gianello
Summary: The study investigated the glucagon secretion characteristics of pig islet cells and found that high glucose concentration significantly inhibited glucagon secretion. In vivo experiments showed a quick decrease in plasma glucagon and a slower increase in plasma insulin after glucose injection.
FRONTIERS IN ENDOCRINOLOGY
(2022)
Article
Environmental Sciences
Michela Novelli, Pascale Beffy, Matilde Masini, Chiara Vantaggiato, Luisa Martino, Lorella Marselli, Piero Marchetti, Vincenzo De Tata
Summary: Exposure to environmental pollutant TCDD affects pancreatic islets, especially beta cells, leading to cell death, ultrastructural alterations, decreased insulin secretion, and changes in gene expression. TCDD exposure significantly reduces cell survival and insulin secretion, causes ultrastructural changes in beta cells, and alters gene expression profiles in isolated islets.
Article
Multidisciplinary Sciences
Waseem El-Huneidi, Shabana Anjum, Abdul Khader Mohammed, Hema Unnikannan, Rania Saeed, Khuloud Bajbouj, Eman Abu-Gharbieh, Jalal Taneera
Summary: The study revealed that CPNE3 plays a crucial role in maintaining normal beta-cell function, with its silencing impairing insulin secretion and beta-cell function. This finding suggests CPNE3 as a potential new target for future management of type 2 diabetes therapy.
SCIENTIFIC REPORTS
(2021)
Article
Endocrinology & Metabolism
Maximilian M. Menger, Lisa Nalbach, Leticia P. Roma, Matthias W. Laschke, Michael D. Menger, Emmanuel Ampofo
Summary: Exposing isolated pancreatic islets to EPO does not affect viability and ROS production, but increases CD31-positive cells and insulin/VEGF-A gene expression. EPO-cultivated islets exhibit accelerated revascularization post-transplantation compared to controls, suggesting EPO as a promising approach for clinical islet transplantation.
ACTA DIABETOLOGICA
(2021)
Article
Endocrinology & Metabolism
Gyeong-Jin Cheon, Heon-Seok Park, Eun-Young Lee, Min Jung Kim, Young-Hye You, Marie Rhee, Ji-Won Kim, Kun-Ho Yoon
Summary: This study demonstrates the accelerated differentiation and immune-tolerant properties of neonatal porcine pancreatic cell clusters (NPCCs) through in vitro chemical treatment and microencapsulation. The differentiated NPCCs showed increased insulin-positive cells and improved transplant efficacy in diabetic mice without immune rejection.
DIABETES & METABOLISM JOURNAL
(2022)
Article
Biochemical Research Methods
Friederike A. Sandbaumhuter, Mariya Nezhyva, Olle Eriksson, Adam Engberg, Johan Kreuger, Per E. Andren, Erik T. Jansson
Summary: Filter-aided sample preparation (FASP) is widely used in bottom-up proteomics for tryptic digestion, but the sample recovery yield is limited by the amount of starting material. We developed and optimized a flexible well-plate mu FASP device and protocol suitable for a similar to 1 mu g protein sample. Compared to the standard FASP protocol, the mu FASP method significantly increased the number of identified proteins. We also conducted a peptidomic and proteomic study of single pancreatic islets using the well-plate mu FASP, revealing inter-islet heterogeneity in the expression of proteins involved in glucose catabolism, pancreatic hormone processing, and secreted peptide hormones.
JOURNAL OF PROTEOME RESEARCH
(2022)
Article
Physics, Multidisciplinary
Tatiana Latychevskaia
Summary: In this study, a new method is proposed to reconstruct 3D sample distribution from a single 2D intensity measurement, exceeding the classical limit in z resolution. This method is practical for radiation-sensitive materials or experimental setups with constraints on the number of intensity measurements.
PHYSICAL REVIEW LETTERS
(2021)
Article
Cell Biology
Jungwon Wee, Sungmin Pak, Tahnbee Kim, Gyu-Sang Hong, Ji Seon Lee, Jinyan Nan, Hyungsup Kim, Mi-Ock Lee, Kyong Soo Park, Uhtaek Oh
Summary: Insulin plays a critical role in regulating glucose homeostasis, while the mechanosensitive channel Tentonin 3/TMEM150C (TTN3) is involved in glucose-stimulated insulin secretion by mediating cation influx in beta-cells.
Article
Chemistry, Analytical
Shao-Kang Hung, Yu-Hsin Chung, Cheng-Lung Chen, Kai-Hung Chang
Summary: This article introduces an optoelectronic sensor that can measure the inclinations of a mirror in two dimensions simultaneously, suitable for precision laser machining. With a wide measuring range and high resolution, this sensor allows for closed-loop control, meeting the requirements of miniature laser engravers.
Article
Engineering, Electrical & Electronic
Hongye Wang, Lingzhi Meng, Qi Xia, Shitai Yang, Tingting Yuan, Xiaotong Zhang, Libo Yuan
Summary: A bending sensor is proposed to convert the multichannel bending signals of multicore fiber (MCF) to single-channel signals using the phase mask method combined with the thermal diffusion technique (TDT). The sensor was fabricated using a four-core fiber (FCF) with different resonant wavelengths for each fiber core through the method of core-by-core inscribed fiber Bragg gratings (FBGs). Single-channel measurement of the 3-D parallel FCF FBGs signals was achieved by coupling the FCF with a single-mode fiber (SMF) using the TDT method. The sensor demonstrated high bending sensitivities and eliminated crosstalk caused by temperature and strain.
IEEE SENSORS JOURNAL
(2023)
Article
Chemistry, Analytical
Danlei Li, Christopher Batchelor-McAuley, Richard G. Compton
Summary: An amperometric method was used to measure oxygen content in sheep's blood, with a linear relationship observed between chronoamperometric current and oxygen concentration. Additionally, this study presents the first investigation of direct voltammetry in sheep's blood and proposes a dissociative CE process to explain the electrochemical behavior of oxygen reduction.
Article
Chemistry, Analytical
Jaehwan Ahn, Kwang Bo Jung, Ohman Kwon, Mi-Sun Choi, Jun-Ho Ahn, Hyoung-Yun Han, Cho-Rok Jung, Seokjoo Yoon, Mi-Young Son, Jung-Hwa Oh
Summary: A quantitative method using impedance spectroscopy was developed to evaluate the epithelial cell membrane integrity of HIOs, reflecting their functionality and maturity. Treatment with IL-2 resulted in higher expression of intestinal maturation- and tight junction-related markers in HIOs matured in vitro, indicating increased integrity. A multi-microchannel system controlled by inhalation pressure enhanced the stability and sensitivity of the impedance signal.
ANALYTICAL CHEMISTRY
(2021)
Article
Chemistry, Multidisciplinary
Qianyun Tang, Dandan Wang, Jinhui Cui, Yiheng Zhang, Junyang Mei, Jing Du, Anyue Xia, Qian Sun, Dan Luo, Baosan Han, Mingzhe Gan, Peifeng Liu
Summary: This study presents a novel microfluidic platform for precise and flexible control of oxygen concentrations in microbial suspension culture. The platform demonstrates unique capabilities for spatiotemporal gas control and detection, allowing for applications in screening, studying, and culturing industrial or niche-specific environmental microbiomes.
Review
Chemistry, Physical
Yingwen Chen, Jia Song, Qingyu Ruan, Xi Zeng, Lingling Wu, Linfeng Cai, Xuanqun Wang, Chaoyong Yang
Summary: Cells are fundamental building blocks of biological systems, and studying single cells can provide insights into cell diversity and disease processes. Single-cell RNA sequencing technologies allow cellular heterogeneity to be dissected at unprecedented resolution.
Article
Medicine, Research & Experimental
Yves Mugabo, Cheng Zhao, Ju Jing Tan, Anindya Ghosh, Scott A. Campbell, Evgenia Fadzeyeva, Frederic Pare, Siew Siew Pan, Maria Galipeau, Julia Ast, Johannes Broichhagen, David J. Hodson, Erin E. Mulvihill, Sophie Petropoulos, Gareth E. Lim
Summary: While 14-3-3 proteins are crucial for neurotransmitter synthesis, specific isoform 14-3-3i; plays a critical role in regulating beta cell function by enhancing glucose-stimulated insulin secretion, mitochondrial function, and ATP synthesis. Deletion or inhibition of 14-3-3i; leads to alterations in beta cell transcriptome, particularly upregulating genes associated with mitochondrial respiration and oxidative phosphorylation, suggesting its importance in insulin secretion control.
Article
Polymer Science
Vincenzo Calabrese, Csilla Gyorgy, Simon J. Haward, Thomas J. Neal, Steven P. Armes, Amy Q. Shen
Summary: This study investigates the flow behavior of dispersions composed of different worm-like nanoparticles (WLNPs) under shear and extensional flows. The results show that extensional deformations are more effective than shear deformations at causing alignment of the WLNPs.
Letter
Mechanics
San To Chan, Simon J. Haward, Amy Q. Shen
Summary: Edge fracture, a common problem in measuring rheological properties of viscoelastic fluids at high shear rates, can be delayed by sealing the fluid's free surface with nontoxic liquid metal Galinstan. This approach extends the measurable shear rate range of a cone-and-plate fixture significantly, compared to the existing method of using a cone-partitioned plate fixture. The inexpensive yet effective method proposed in this study will benefit the general rheological study of complex fluids.
Article
Biochemical Research Methods
Vincenzo Calabrese, Amy Q. Q. Shen, Simon J. J. Haward
Summary: This article analyzes the structural dynamics of naturally derived colloidal rods (CR) under microfluidic flows, focusing on shear- and extensional-dominated flows. It highlights the importance of understanding key concepts when evaluating results from different CR and microfluidic platforms, and suggests future research directions.
Article
Chemistry, Multidisciplinary
Vincenzo Mazzaracchio, Mauricio Rios Maciel, Tatiana Porto Santos, Kazumi Toda-Peters, Amy Q. Shen
Summary: A duplex electrochemical immunosensor is developed for simultaneous detection of anti-nucleocapsid IgG (N-IgG) and anti-spike IgG (S-IgG) using a two-working electrode system and differential pulse voltammetry. The sensor exhibits enhanced performance by modifying the screen-printed electrodes with carbon black and electrodeposited gold nanoflowers. It achieves a wide linear range and low detection limits for N-IgG and S-IgG detection in serum samples. Integrated into a microfluidic device, the duplex immunosensor enables high throughput screening for COVID-19 and other infectious diseases with significantly reduced detection time.
Review
Physics, Fluids & Plasmas
Charlotte de Blois, Simon J. Haward, Amy Q. Shen
Summary: In the flow of viscoelastic fluids over a microfluidic canopy, waves in the form of low flow velocity regions compared to the surrounding flow spontaneously emerge. The occurrence of these waves is chaotic and exhibits characteristics of elastic turbulence. By combining flow velocimetry experiments and high-speed tracking of the pillars, we systematically study the coupling between the low-velocity waves and the microfluidic canopy.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Biochemistry & Molecular Biology
Marvin Detert, Tatiana Porto Santos, Amy Q. Shen, Vincenzo Calabrese
Summary: The relationship between the alignment of biosourced rod-like colloids (RC) and rod-like polymers (RP) and the rheological properties of the fluid is investigated. It is found that the alignment of RC and RP contributes to the viscosity of the fluid in a consistent manner across different systems, independent of concentration. A dimensionless parameter (& beta;) directly proportional to the specific viscosity (& eta;(sp)) at zero shear rate (& eta;(0,sp)) is also identified.
Article
Mechanics
Simon J. Haward, Francisco Pimenta, Stylianos Varchanis, Daniel W. Carlson, Kazumi Toda-Peters, Manuel A. Alves, Amy Q. Q. Shen
Summary: Numerical optimization of a six-arm cross-slot device generates three-dimensional fluidic channel shapes that approximate ideal uniaxial (biaxial) stagnation point extensional flow. One of the designed geometries is suitable for microfabrication and achieves optimal flow fields for both Newtonian and viscoelastic fluids. The geometry is called OUBER and is fabricated with high precision by laser-induced etching. Microtomographic-particle image velocimetry measurements confirm accurate imposition of desired flows in a wide region around the stagnation point. In Part II of the paper, pressure drop measurements in the OUBER geometry are used to evaluate extensional rheometry of dilute polymeric solutions compared to planar extension measurements using OSCER.
JOURNAL OF RHEOLOGY
(2023)
Article
Mechanics
Simon J. Haward, Stylianos Varchanis, Gareth H. McKinley, Manuel A. Alves, Amy Q. Shen
Summary: Part I presents a microfluidic device for generating near-homogeneous uniaxial and biaxial elongational flows. In Part II, this device is used to examine the extensional rheology of dilute polymer solutions compared to measurements made under planar extension. The extension rate and tensile stress difference generated in the fluid are measured using micro-particle image velocimetry and excess pressure drop measurements. The results show that at higher polymer concentrations, the experimental measurements deviate from the model predictions due to intermolecular interactions as the polymer chains unravel in the extensional flows.
JOURNAL OF RHEOLOGY
(2023)
Article
Mechanics
San To Chan, Stylianos Varchanis, Simon J. Haward, Amy Q. Shen
Summary: Edge fracture is a viscoelastic instability that occurs when a fluid experiences a high shear rate, causing sudden indentation of its free surface. This fracture can affect rheological measurements and lead to complications in interpreting experimental results. Through empirical and theoretical research, the physics of edge fracture has been unraveled, enabling rheologists to develop techniques for reducing its adverse effects. Furthermore, edge fracture has potential applications in breaking viscoelastic liquid bridges, making it useful for functional dispensing nozzles.
JOURNAL OF RHEOLOGY
(2023)
Article
Mechanics
M. A. Kanso, V. Calabrese, Amy Q. Q. Shen, Myong Chol Pak, A. J. Giacomin
Summary: Bacteriophages are viruses that attack bacteria by attaching to their receptors, and their reorientation relies on Brownian motion and rotational components. In this study, the rotational diffusivity of Pf1, a type of bacteriophage, was determined through rheological measurements and compared with theoretical predictions. The results showed that the dimensionless rotational diffusivity differed by approximately one order of magnitude from the value obtained from fluorescence microscopy. Good agreement was found between theoretical predictions and complex viscosity measurements at low frequency.
Article
Chemistry, Physical
Arisa Yokokoji, Stylianos Varchanis, Amy Q. Shen, Simon J. Haward
Summary: Viscoelastic flows in the cross-slot geometry can transition from a steady symmetric state to a steady asymmetric state. This transition may be due to purely-elastic effects beyond a critical flow rate, or shear thinning of the fluid's viscosity. The interplay between fluid elasticity and shear thinning affects the onset and development of asymmetric flows. Experimental results and numerical simulations reveal the importance of shear thinning and fluid elasticity in controlling elastic instabilities in the cross-slot geometry.
Article
Multidisciplinary Sciences
San To Chan, Stylianos Varchanis, Amy Q. Shen, Simon J. Haward
Summary: This study investigates the possibility of using torsion to break liquid bridges of complex thixotropic elastoviscoplastic fluids and demonstrates its potential application in improving the dispensing of real industrial fluids. Through simulation and dimensional analysis, a better understanding of the liquid bridge breaking mechanism is achieved.
Article
Chemistry, Physical
Cameron C. Hopkins, Amy Q. Shen, Simon J. Haward
Summary: This study investigates the flow of a viscoelastic wormlike micellar solution around cylinders in straight microchannels. The results reveal the presence of different flow states depending on the blockage ratio range.
Article
Chemistry, Physical
Cameron C. Hopkins, Simon J. Haward, Amy Q. Shen
Summary: This study investigates a novel flow instability in a viscoelastic micellar solution as it flows past a microcylinder in a channel. The instability manifests as bending of streamlines near the upstream pole of the cylinder and the formation of wall-attached vortices. As the Weissenberg number increases, the flow becomes time dependent with pulsations. Beyond a fourth critical value, a fluctuating vortex forms attached to the upstream pole of the cylinder.
Article
Chemistry, Physical
Atsushi Matsumoto, Amy Q. Shen
Summary: The ion diameter of ionic liquids (ILs) has a significant influence on the shear viscosity of polymerized ionic liquids (PILs) in IL solutions. The specific viscosity first decreases and then increases with increasing IL concentration when both PIL and IL contain large PFSI anions, attributed to the charge underscreening phenomenon. However, when PIL and IL contain small BF4 anions, the specific viscosity decreases asymptotically with increasing IL concentration due to full charge screening.