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N-methyl Formamide Electrolyte Additive Enabling Highly Reversible Zn Anodes. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2400673. [PMID: 38700057 DOI: 10.1002/smll.202400673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2024] [Revised: 04/25/2024] [Indexed: 05/05/2024]
Abstract
Parasitic side reactions and dendrites formation hinder the application of aqueous zinc ion batteries due to inferior cycling life and low reversibility. Against this background, N-methyl formamide (NMF), a multi-function electrolyte additive is applied to enhance the electrochemical performance. Studied via advanced synchrotron radiation spectroscopy and DFT calculations, the NMF additive simultaneously modifies the Zn2+ solvation structure and ensures uniform zinc deposition, thus suppressing both parasitic side reactions and dendrite formation. More importantly, an ultralong cycling life of 3115 h in the Zn||Zn symmetric cell at a current density of 0.5 mA cm-2 is achieved with the NMF additive. Practically, the Zn||PANI full cell utilizing NMF electrolyte shows better rate and cycling performance compared to the pristine ZnSO4 aqueous electrolyte. This work provides useful insights for the development of high-performance aqueous metal batteries.
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Switched step integral backstepping control for nonlinear motion systems with application to a laboratory helicopter. ISA TRANSACTIONS 2023; 141:470-481. [PMID: 37507325 DOI: 10.1016/j.isatra.2023.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 07/02/2023] [Accepted: 07/02/2023] [Indexed: 07/30/2023]
Abstract
In this paper, the energy efficiency of the widespread application of backstepping control to a class of nonlinear motion systems is investigated. A Switched Step Integral Backstepping Control (SSIBC) scheme is introduced to improve immunity to measurement noise and to increase the energy efficiency of conventional backstepping in practice. The SSIBC is realized by switching between two candidate controllers obtained at different steps of the iterative backstepping design process. A bi-state dependent hysteresis rule is developed to supervise stable switching between the different regimes in the presence of noise. The proposed method is experimentally verified on a MIMO twin rotor laboratory helicopter involving coupled nonlinear dynamics, inaccessible states and uncertainties. Experimental results show that in addition to a reduction in power consumption, the SSIBC reduces saturation of the control signal and visible motor jerking in contrast with conventional backstepping. Additional comparisons with a previously proposed optimized decoupling PID controller also show significant improvement in precision achieved with higher energy efficiency. Experimental results obtained with the introduction of an external disturbance into the system also show the robustness of the proposed SSIBC.
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Stress perceived by drivers in public healthcare facilities in Negeri Sembilan during the first year of the COVID-19 pandemic. THE MEDICAL JOURNAL OF MALAYSIA 2023; 78:653-660. [PMID: 37775494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 10/01/2023]
Abstract
INTRODUCTION Healthcare drivers, including ambulance drivers, were less concerned about health and safety during the COVID-19 pandemic, with not only the risk of COVID-19 infection but also a higher risk of prolonged states of alertness, stress, burnout, fatigue and road traffic accident. This study aimed to determine the prevalence of stress and its associated factors among healthcare drivers, especially during the COVID-19 pandemic. MATERIALS AND METHODS This study employs a crosssectional study design and utilises self-reported data obtained from locally validated personal stress inventory questionnaires. The data collection period spanned from August 1 to 31, 2020. The study sample consisted of 163 healthcare drivers affiliated with the Negeri Sembilan State Health Department. The Chi-square test and Fisher's exact test were the first used to determine the association between variables prior to conducting multiple logistic regression to predict the relationship between dependent and independent variables. RESULTS In COVID-19's first year, 7.4% (n = 12) of healthcare drivers reported perceived stress with ambulance drivers reporting more stress (10.6%; n = 5) than non-ambulance drivers (6.0%; n = 7). Simple statistical analysis identified perceived stress significantly associated with household income, smoking status and performing on-call. Further analysis by multiple logistic regression found that perceived stress was significantly related to smoking (aOR 19.9, 95% CI: 1.86-213.90), and performing on-call (aOR 8.69, 95% CI 1.21-62.28). Nevertheless, no association was found between perceived stress and age, ethnicity, marital status, education, household income, co-morbidities, driving assignment, employment duration, needing a part-time job or motor vehicle accident history. CONCLUSION The study found that the perceived stress amongst Malaysian healthcare drivers during the COVID-19 pandemic was relatively low. This could be due to fewer lifethreatening tasks, emergencies, assigned tasks and increase income due to overtime during the COVD-19 pandemic. The OSH team's efforts to provide consistent safety and health training, including stress management, may have contributed to the healthcare driver's ability to effectively manage the stressful circumstances encountered during the pandemic. In order to enhance salary competitiveness, employers should provide financial management education alongside subsidised housing and childcare provisions. Healthcare drivers who smoke should be taught different stress reduction techniques so that they can handle their stress in a healthy way.
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Curcumin exerts its antioxidant and neuroprotective effects against aluminum-induced oxidative stress and neurotoxicity in male albino rats. ACTA SCIENTIARUM. BIOLOGICAL SCIENCES 2023; 45:e64651. [DOI: 10.4025/actascibiolsci.v45i1.64651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
Aluminum is a neurotoxicant and one of the most harmful metals in the environment; it is producing tissue inflammation and oxidative stress. Curcumin is an effective antioxidant and neuroprotective compound with medicinal potential. Curcumin's effect on AL toxicity was investigated in this study. Two groups of 70 mature adult albino rats were used, each of which was subdivided into five groups: Control, Vehicle, Curcumin, Aluminum, and Curcumin + Aluminum group. For two periods of 20 and 40 days, animal models were administered orally AlCl3 (20 mg kg-1 bw) and/or Curcumin (100 mg kg-1 bw). In the cerebral cortex, aluminum caused a significant rise (p < 0.05) in lipid peroxidation and DNA fragmentation, as well as a significant decrease (p < 0.05) in antioxidant enzymes such as catalase, superoxide dismutase, and glutathione peroxidase. In the brain hippocampus, aluminum caused a major reduction (p < 0.05) in neurotransmitters (dopamine and serotonin), while Acetylcholine esterase activity increased sharply (p < 0.05). Aluminum also triggered histological analyses in the hippocampus of the brain. Curcumin co-administration considerably reduced the increase in lipid peroxidation and DNA fragmentation, but also enhanced the depletion of antioxidant enzymes. Curcumin also reversed the decline in neurotransmitters, the increase in Acetylcholine esterase, and the distortion in the brain hippocampus.
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Association of Dyslipidemia with Endometriosis: A Case Control Study. Mymensingh Med J 2023; 32:118-124. [PMID: 36594311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Endometriosis is a chronic multi-factorial disease characterized by the presence of functioning uterine glands and stroma in any site outside the uterus. Despite the major public health impact of this condition, little is known about their etiologies. Some studies focused on the similarities between the common biological mechanisms underlying the development of endometriosis and atherosclerotic plaques. So, it is possible to hypothesize that same atherogenic risk factors, such as dyslipidemia may play a role in endometriosis pathogenesis. This case-control study was carried out in the department of Obstetrics and Gynaecology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh from September 2018 to August 2019 to investigate the lipid profile in patients with endometriosis and to analyze the association of dyslipidemia with endometriosis. A total of 140 participants ranged between 18 and 35 years of age attending BSMMU were enrolled in the study. The study population was divided into case and control group; the case group consisting of patients with endometriosis and control group comprising of healthy women without endometriosis. Fasting lipid profile of all participants was measured in the department of Biochemistry and Molecular Biology of BSMMU, Bangladesh. Doing student's t-test and Chi square test compared results of both groups. Logistic regression analysis was done to see association of dyslipidemia with endometriosis. Women with endometriosis were found to have significantly higher levels of serum total cholesterol (TC), low density lipoprotein (LDL-C), triglyceride (TG) and significantly lower level of high density lipoprotein (HDL-C) compared to the controls (p<0.05). The mean atherogenic index was significantly higher in case group (p<0.05). This study found an association between dyslipidemia and endometriosis.Women with endometriosis have higher atherogenic index compared to women without endometriosis.
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Study on Lithium Extraction from Salt Lake Brines. THEORETICAL FOUNDATIONS OF CHEMICAL ENGINEERING 2022. [DOI: 10.1134/s0040579522060252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Nanoscale Features of Tunable Bacterial Outer Membrane Models Revealed by Correlative Microscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:8773-8782. [PMID: 35748045 PMCID: PMC9330759 DOI: 10.1021/acs.langmuir.2c00628] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The rise of antibiotic resistance is a growing worldwide human health issue, with major socioeconomic implications. An understanding of the interactions occurring at the bacterial membrane is crucial for the generation of new antibiotics. Supported lipid bilayers (SLBs) made from reconstituted lipid vesicles have been used to mimic these membranes, but their utility has been restricted by the simplistic nature of these systems. A breakthrough in the field has come with the use of outer membrane vesicles derived from Gram-negative bacteria to form SLBs, thus providing a more physiologically relevant system. These complex bilayer systems hold promise but have not yet been fully characterized in terms of their composition, ratio of natural to synthetic components, and membrane protein content. Here, we use correlative atomic force microscopy (AFM) with structured illumination microscopy (SIM) for the accurate mapping of complex lipid bilayers that consist of a synthetic fraction and a fraction of lipids derived from Escherichia coli outer membrane vesicles (OMVs). We exploit the high resolution and molecular specificity that SIM can offer to identify areas of interest in these bilayers and the enhanced resolution that AFM provides to create detailed topography maps of the bilayers. We are thus able to understand the way in which the two different lipid fractions (natural and synthetic) mix within the bilayers, and we can quantify the amount of bacterial membrane incorporated into the bilayer. We prove the system's tunability by generating bilayers made using OMVs engineered to contain a green fluorescent protein (GFP) binding nanobody fused with the porin OmpA. We are able to directly visualize protein-protein interactions between GFP and the nanobody complex. Our work sets the foundation for accurately understanding the composition and properties of OMV-derived SLBs to generate a high-resolution platform for investigating bacterial membrane interactions for the development of next-generation antibiotics.
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Impedance sensing of antibiotic interactions with a pathogenic E. coli outer membrane supported bilayer. Biosens Bioelectron 2022; 204:114045. [PMID: 35180690 PMCID: PMC9526520 DOI: 10.1016/j.bios.2022.114045] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 01/19/2022] [Accepted: 01/25/2022] [Indexed: 11/18/2022]
Abstract
Antibiotic resistance is a growing global health concern due to the decreasing number of antibiotics available for therapeutic use as more drug-resistant bacteria develop. Changes in the membrane properties of Gram-negative bacteria can influence their response to antibiotics and give rise to resistance. Thus, understanding the interactions between the bacterial membrane and antibiotics is important for elucidating microbial membrane properties to use for designing novel antimicrobial drugs. To study bacterial membrane-antibiotic interactions, we created a surface-supported planar bacterial outer membrane model on an optically-transparent, conducting polymer surface (poly (3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)). This model enables membrane characterization using fluorescence microscopy and electrochemical impedance spectroscopy (EIS). The membrane platform is fabricated using outer membrane vesicles (OMVs) isolated from clinically relevant Gram-negative bacteria, enterohemorrhagic Escherichia coli. This approach enables us to mimic the native components of the bacterial membrane by incorporating native lipids, membrane proteins, and lipopolysaccharides. Using EIS, we determined membrane impedance and captured membrane-antibiotic interactions using the antibiotics polymyxin B, bacitracin, and meropenem. This sensor platform incorporates aspects of the biological complexity found in bacterial outer membranes and, by doing so, offers a powerful, biomimetic approach to the study of antimicrobial drug interactions.
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Bioelectronic Platform to Investigate Charge Transfer between Photoexcited Quantum Dots and Microbial Outer Membranes. ACS APPLIED MATERIALS & INTERFACES 2022; 14:15799-15810. [PMID: 35344337 DOI: 10.1021/acsami.1c25032] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Photosynthetic semiconductor biohybrids (PSBs) convert light energy to chemical energy through photo-driven charge transfer from nanocrystals to microorganisms that perform bioreactions of interest. Initial proof-of-concept PSB studies with an emphasis on enhanced CO2 conversion have been encouraging; however, bringing the broad prospects of PSBs to fruition is contingent on establishing a firm fundamental understanding of underlying interfacial charge transfer processes. We introduce a bioelectronic platform that reduces the complexity of PSBs by focusing explicitly on interactions between colloidal quantum dots (QDs), microbial outer membranes, and native, small-molecule redox mediators. Our model platform employs a standard three-electrode electrochemical cell with supported outer membranes of Pseudomonas aeruginosa, pyocyanin redox mediators, and semiconducting CdSe QDs dispersed in an aqueous electrolyte. We present a comprehensive electrochemical analysis of this platform via electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and chronoamperometry (CA). EIS reveals the formation and electronic properties of supported outer membrane films. CV reveals the electrochemically active surface area of P. aeruginosa outer membranes and that pyocyanin is the sole species that performs redox with these outer membranes under sweeping applied potential. CA demonstrates that photoexcited charge transfer in this system is driven by the reduction of pyocyanin at the QD surface followed by diffusion of reduced pyocyanin through the outer membrane. The broad applicability of this platform across many bacterial species, QD architectures, and controlled environmental conditions affords the possibility to define design principles for future PSB systems to synergistically integrate concurrent advances in genetically engineered organisms and inorganic nanomaterials.
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Dual Mode Sensing of Binding and Blocking of Cancer Exosomes to Biomimetic Human Primary Stem Cell Surfaces. ACS Biomater Sci Eng 2021; 7:5585-5597. [PMID: 34802228 DOI: 10.1021/acsbiomaterials.1c01056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cancer-derived exosomes (cEXOs) facilitate transfer of information between tumor and human primary stromal cells, favoring cancer progression. Although the mechanisms used during this information exchange are still not completely understood, it is known that binding is the initial contact established between cEXOs and cells. Hence, studying binding and finding strategies to block it are of great therapeutic value. However, such studies are challenging for a variety of reasons, including the need for human primary cell culture, the difficulty in decoupling and isolating binding from internalization and cargo delivery, and the lack of techniques to detect these specific interactions. In this work, we created a supported biomimetic stem cell membrane incorporating membrane components from human primary adipose-derived stem cells (ADSCs). We formed the supported membrane on glass and on multielectrode arrays to offer the dual option of optical or electrical detection of cEXO binding to the membrane surface. Using our platform, we show that cEXOs bind to the stem cell membrane and that binding is blocked when an antibody to integrin β1, a component of ADSC surface, is exposed to the membrane surface prior to cEXOs. To test the biological outcome of blocking this interaction, we first confirm that adding cEXOs to cultured ADSCs leads to the upregulation of vascular endothelial growth factor, a measure of proangiogenic activity. Next, when ADSCs are first blocked with anti-integrin β1 and then exposed to cEXOs, the upregulation of proangiogenic activity and cell proliferation are significantly reduced. This biomimetic membrane platform is the first cell-free label-free in vitro platform for the recapitulation and study of cEXO binding to human primary stem cells with potential for therapeutic molecule screening as it is compatible with scale-up and multiplexing.
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Abstract
Antibiotic resistance is a growing global health concern that has been increasing in prevalence over the past few decades. In Gram-negative bacteria, the outer membrane is an additional barrier through which antibiotics must traverse to kill the bacterium. In addition, outer membrane features and properties, like membrane surface charge, lipopolysaccharide (LPS) length, and membrane porins, can be altered in response to antibiotics and therefore, further mediate resistance. Model membranes have been used to mimic bacterial membranes to study antibiotic-induced membrane changes but often lack the compositional complexity of the actual outer membrane. Here, we developed a surface-supported membrane platform using outer membrane vesicles (OMVs) from clinically relevant Gram-negative bacteria and use it to characterize membrane biophysical properties and investigate its interaction with antibacterial compounds. We demonstrate that this platform maintains critical features of outer membranes, like fluidity, while retaining complex membrane components, like OMPs and LPS, which are central to membrane-mediated antibiotic resistance. This platform offers a non-pathogenic, cell-free surface to study such phenomena that is compatible with advanced microscopy and surface characterization tools like quartz crystal microbalance. We confirm these OMV bilayers recapitulate membrane interactions (or lack thereof) with the antibiotic compounds polymyxin B, bacitracin, and vancomycin, validating their use as representative models for the bacterial surface. By forming OMV bilayers from different strains, we envision that this platform could be used to investigate underlying biophysical differences in outer membranes leading to resistance, to screen and identify membrane-active antibiotics, or for the development of phage technologies targeting a particular membrane surface component.
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Preparation of Low Fat Probiotic Yoghurt Supplemented with Pomegranate Pomace Powder as Source of Antioxidant Dietary Fibers. JOURNAL OF FOOD AND DAIRY SCIENCES 2021; 12:211-215. [DOI: 10.21608/jfds.2021.201809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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CD68-positive tumour associated macrophages, PD-L1 expression, and EBV latent infection in a high HIV-prevalent South African cohort of Hodgkin lymphoma patients. Pathology 2021; 53:628-634. [PMID: 33558066 DOI: 10.1016/j.pathol.2020.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/30/2020] [Accepted: 11/02/2020] [Indexed: 10/22/2022]
Abstract
A higher proportion of CD68-positive tumour associated macrophages (TAMs) has been associated with poorer outcomes in HIV-negative patients with Hodgkin lymphoma (HL), but whether this is true in HIV-positive patients with HL is not known. In this study, we investigated the number of CD68-positive TAMs and expression of programmed cell death-ligand 1 (PD-L1) in lymph node specimens from HL patients and correlated expression with clinical features (HIV status, disease severity and survival) and histopathological features (EBV latent positivity and subtype of HL). We stained archived lymph node specimens from 77 patients diagnosed with HL for CD68 and PD-L1. Stains were graded as: CD68 low (≤25%), CD68 high (>25%), PD-L1 low (≤50%), and PD-L1 high (>50%). Expression levels were correlated with the clinical and histopathological features using bivariate and multivariate analyses. Survival was analysed by overall and progression-free survival. Thirty-four of the 77 included patients (44%) were HIV-positive. EBV latency was detected in 97% of HIV-positive HL patients and in 14% of HIV-negative HL patients. A high CD68 score was associated with lower median haemoglobin levels (9.4 vs 11.4 g/dL; p=0.02), platelet numbers (262 vs 424 cells ×109/L; p=0.01), and lymphocyte numbers (0.99 vs 1.70 cells ×109/L, p=0.01) and a trend towards advanced disease (international prognostic score ≥4; hazard ratio 2.4; confidence interval 0.89-6.47; p=0.08). HIV status did not affect CD68 or PD-L1 expression. A higher proportion of CD68-positive TAMs was found in samples that were EBV-positive. HIV positivity and EBV negativity correlated with poorer survival. CD68 and PD-L1 expression were not predictive of survival. High CD68 expression was associated with EBV positivity but not HIV positivity and did not predict adverse outcomes. PD-L1 expression was unaffected by HIV status or EBV positivity and did predict adverse outcomes.
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Cyclophilin A (CyPA) as a Novel Biomarker for Early Detection of Diabetic Nephropathy in an Animal Model. Diabetes Metab Syndr Obes 2020; 13:3807-3819. [PMID: 33116728 PMCID: PMC7585800 DOI: 10.2147/dmso.s260293] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 09/04/2020] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND AIM Type 2 diabetes mellitus (DM) is the most common single cause of the end-stage renal disease (ESRD). Cyclophilin A (CyPA) is an 18-kD protein. The connection between diabetic nephropathy (DN) and the secreted form of CyPA (sCyPA) has been elucidated in this study that aims to investigate sCyPA correlation with renal dysfunction. MATERIALS AND METHODS Thirty-four male adult Wistar rats weighing 180-220 g were used. Animals were divided into a study group and a control group, 17 rats in each. Streptozotocin (STZ) and nicotine amide were used to damage some pancreatic cells for induction of type 2 DM. Comparison was made between the study and the control groups. Moreover, a comparison was made between the members of the study group before and after induction of DN. RESULTS The rat model that exhibited a higher concentration of urinary sCyPA was detected early in the eighth week. There was a significantly higher level of 24-h urinary CyPA in the study group compared to the control group (p-value=0.004) and there was a significant elevation in the 24-h urinary Cyp-A in the study group after injection of STZ compared to the values before injection (p-value <0.001). Immunohistochemical analysis of renal tissue revealed that the mean expression of CyPA was higher in the study group than in the control group. For the urinary 24-h CYP-A, using a cutoff of 1.15 ng/mL, the accuracy was 72.4%, sensitivity was (77.8%) and specificity was (67%). CONCLUSION According to this animal study, we proved that CyPA is a valuable marker for DN. It is a more sensitive, noninvasive and rapid biomarker for early detection of any renal affection in human diabetic patients.
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Independently Licensed Counselors' Work Values. COUNSELING AND VALUES 2020. [DOI: 10.1002/cvj.12140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Supported Membrane Platform to Assess Surface Interactions between Extracellular Vesicles and Stromal Cells. ACS Biomater Sci Eng 2020; 6:3945-3956. [PMID: 33463350 DOI: 10.1021/acsbiomaterials.0c00133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Extracellular vesicles (EVs) are membrane-encapsulated particles secreted by eukaryotic cells that stimulate cell communication and horizontal cargo exchange. EV interactions with stromal cells can result in molecular changes in the recipient cell and, in some cases, lead to disease progression. However, mechanisms leading to these changes are poorly understood. A few model systems are available for studying the outcomes of surface interactions between EV membranes with stromal cells. Here, we created a hybrid supported bilayer incorporating EVs membrane material, called an extracellular vesicle supported bilayer, EVSB. Using EVSBs, we investigated the surface interactions between breast cancer EVs and adipose-derived stem cells (ADSCs) by culturing ADSCs on EVSBs and analyzing cell adhesion, spreading, viability, vascular endothelial growth factor (VEGF) secretion, and myofibroblast differentiation. Results show that cell viability, adhesion, spreading, and proangiogenic activity were enhanced, conditions that promote oncogenic activity, but cell differentiation was not. This model system could be used to develop therapeutic strategies to limit EV-ADSC interactions and proangiogenic conditions. Finally, this model system is not limited to the study of cancer but can be used to study surface interactions between EVs from any origin and any target cell to investigate EV mechanisms leading to cellular changes in other diseases.
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Improved integral backstepping control of variable speed motion systems with application to a laboratory helicopter. ISA TRANSACTIONS 2020; 97:1-13. [PMID: 31327468 DOI: 10.1016/j.isatra.2019.07.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 05/04/2019] [Accepted: 07/08/2019] [Indexed: 06/10/2023]
Abstract
This paper proposes an improved method of integral backstepping for real time control of a laboratory helicopter with variable speed rotors known as the Two-Rotor Aero-dynamic System (TRAS). The coupled system is decomposed into the horizontal subsystem (HS) and the vertical subsystem (VS) and traditional backstepping, augmented with direct integral action is designed for each subsystem. The transient response to both constant and time varying references is then simultaneously improved by modifying an already proposed method called dual boundary conditional integration. A switching technique is also employed to enhance the tracking response of the undamped HS for its bi-directional motor which exhibits jerking effects. Experimental results show that the proposed approach yields improved transient and tracking performance when compared to previously proposed methods exploiting conditional integration earlier proposed for improving the transient response of controlled nonlinear systems with integral action. The results also show the robustness of the proposed method in the presence of the coupling effects and additional external disturbance applied to the system in the form of a wind gust.
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Uncovering Biophysical Properties and Interactions of Bacteria Membrane using An Outer Membrane Supported Bilayer. Biophys J 2020. [DOI: 10.1016/j.bpj.2019.11.3348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Abstract
Platelets can be considered as the "guardian of hemostasis" where their main function is to maintain vascular integrity. In pathological conditions, the hemostatic role of platelets may be hijacked to stimulate disease progression. In 1865, Armand Trousseau was a pioneer in establishing the platelet-cancer metastasis relationship, which he eventually termed as Trousseau's Syndrome to describe the deregulation of the hemostasis-associated pathways induced by cancer progression (Varki, Blood. 110(6):1723-9, 2007). Since these early studies, there has been an increase in experimental evidence not only to elucidate the role of platelets in cancer metastasis but also to create novel cancer therapies by targeting the platelet's impact in metastasis. In this chapter, we discuss the contribution of platelets in facilitating tumor cell transit from the primary tumor to distant metastatic sites as well as novel cancer therapies based on platelet interactions.
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Next generation sequencing (NGS) to improve the diagnosis and management of patients with disorders of sex development (DSD). Endocr Connect 2019; 8:100-110. [PMID: 30668521 PMCID: PMC6373624 DOI: 10.1530/ec-18-0376] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 01/16/2019] [Indexed: 11/08/2022]
Abstract
Disorders of sex development (DSDs) are a diverse group of conditions where the chromosomal, gonadal or anatomical sex can be atypical. The highly heterogeneous nature of this group of conditions often makes determining a genetic diagnosis challenging. Prior to next generation sequencing (NGS) technologies, genetic diagnostic tests were only available for a few of the many DSD-associated genes, which consequently had to be tested sequentially. Genetic testing is key in establishing the diagnosis, allowing for personalised management of these patients. Pinpointing the molecular cause of a patient's DSD can significantly impact patient management by informing future development needs, altering management strategies and identifying correct inheritance pattern when counselling family members. We have developed a 30-gene NGS panel, designed to be used as a frontline test for all suspected cases of DSD (both 46,XX and 46,XY cases). We have confirmed a diagnosis in 25 of the 80 patients tested to date. Confirmed diagnoses were linked to mutations in AMH, AMHR2, AR, HSD17B3, HSD3B2, MAMLD1, NR5A1, SRD5A2 and WT1 which have resulted in changes to patient management. The minimum diagnostic yield for patients with 46,XY DSD is 25/73. In 34/80 patients, only benign or likely benign variants were identified, and in 21/80 patients only variants of uncertain significance (VOUS) were identified, resulting in a diagnosis not being confirmed in these individuals. Our data support previous studies that an NGS panel approach is a clinically useful and cost-effective frontline test for patients with DSDs.
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miR-363 confers taxane resistance in ovarian cancer by targeting the Hippo pathway member, LATS2. Oncotarget 2018; 9:30053-30065. [PMID: 30046387 PMCID: PMC6059020 DOI: 10.18632/oncotarget.25698] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Accepted: 06/04/2018] [Indexed: 12/12/2022] Open
Abstract
Ovarian cancer is the most aggressive female reproductive tract tumours. Taxane (paclitaxel; TX) is widely used for ovarian cancer treatment. However, ovarian cancers often acquire chemoresistance. MicroRNAs (miR) have been reported to mediate many tumours'chemoresistance. We investigated the role of miR-363 in the chemoresistance of the ovarian cancer cell line, KF, and its TX-resistant derivative (KF-TX) cells. QRT-PCR indicated that miR-363 was upregulated in KF-TX cells, and introduction of miR-363 into sensitive ovarian cancer cells confers TX-resistance and significantly inhibited the expression of the Hippo member, LATS2, as indicated by viability, clonogenic assay and expression analysis. Furthermore, we validated the role of LATS2 in TX-response by sh-based silencing, which also confers TX-resistance to the ovarian cancer cells. On the other hand, specific inhibitor against miR-363 restored the response to TX in the resistant cells. In addition, miR-363 was found to bind to the 3'-UTR of LATS2 mRNA, confirming that miR-363 directly targets LATS2 as indicated by dual luciferase assay. RT-PCR-based evaluation of miR-363 in a panel of human ovarian tumours revealed its upregulation in most of the tumour tissues identified as resistant while it was downregulated in most of the tissues identified as sensitive ones. Moreover, higher levels of miR-363 in human ovarian cancer specimens were significantly correlated with TX chemoresistance. Taken together, our study reveals the involvement of miR-363 in chemoresistance by targeting LATS2 in ovarian cancers, raising the possibility that combination therapy with a miR-363 inhibitor and TX may increase TX efficacy and reduce the chance of TX-resistance.
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2-step integral backstepping control of the two-rotor aero-dynamical system (TRAS). JOURNAL OF FUNDAMENTAL AND APPLIED SCIENCES 2018. [DOI: 10.4314/jfas.v9i6s.31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Reprogramming in inflammatory response to neuronal damage induced by the brain LPS preconditioning: Possible implications in rat model of Parkinson’s disease. Parkinsonism Relat Disord 2018. [DOI: 10.1016/j.parkreldis.2017.11.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Is universal HLA-B*15:02 screening a cost-effective option in an ethnically diverse population? A case study of Malaysia. Br J Dermatol 2017; 177:1102-1112. [PMID: 28346659 PMCID: PMC5617756 DOI: 10.1111/bjd.15498] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/17/2017] [Indexed: 01/26/2023]
Abstract
BACKGROUND A strong association has been documented between HLA-B*15:02 and carbamazepine-induced severe cutaneous adverse reactions (SCARs) in Asians. Human leucocyte antigen testing is potentially valuable in many countries to facilitate early recognition of patient susceptibility to SCARs. OBJECTIVES To determine the cost-effectiveness of universal HLA-B*15:02 screening in preventing carbamazepine-induced Stevens-Johnson syndrome/toxic epidermal necrolysis in an ethnically diverse Malaysian population. METHODS A hybrid model of a decision tree and Markov model was developed to evaluate three strategies for treating newly diagnosed epilepsy among adults: (i) carbamazepine initiation without HLA-B*15:02 screening (current practice); (ii) universal HLA-B*15:02 screening prior to carbamazepine initiation; and (iii) alternative treatment [sodium valproate (VPA)] prescribing without HLA-B*15:02 screening. Base-case analysis and sensitivity analyses were performed over a lifetime time horizon. Incremental cost-effectiveness ratios were calculated. RESULTS Both universal HLA-B*15:02 screening and VPA prescribing were dominated by current practice. Compared with current practice, universal HLA-B*15:02 screening resulted in a loss of 0·0255 quality-adjusted life years (QALYs) at an additional cost of 707 U.S. dollars (USD); VPA prescribing resulted in a loss of 0·2622 QALYs at an additional cost of USD 4127, owing to estimated differences in antiepileptic treatment efficacy. CONCLUSIONS Universal HLA-B*15:02 screening is unlikely to be a cost-effective intervention in Malaysia. However, with the emergence of an ethnically diverse population in many other countries, this may render HLA-B*15:02 screening a viable intervention when an increasing proportion of the population is at risk and an equally effective yet safer antiepileptic drug is available.
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Abstract LB-323: Comparative miRNA microarray profiling indicates miR-363 promotes chemoresistance in ovarian cancer cells by targeting the Hippo member, LATS2. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-lb-323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Ovarian cancer is the most aggressive female reproductive tract tumours. Taxane (TX) is widely used for ovarian cancer treatment. However, ovarian cancer often acquire chemoresistance. MicroRNAs (miR) have been reported to regulate many tumours’ chemoresistance. Here, we investigated the comparative microRNA expression profile between the ovarian cancer cells and their taxane-resistant counterpart, KF-TX to get novel markers for taxane resistance in ovarian cancer. The array data revealed that miR-486, miR143,miR145 and miR363 are the most upregulated miRNAs in association with TX resistance. However, miR-155, miR-100, miR-31 and miR-629 are the most significantly downregulated miRNAs after resistance development. We then focused on the role of miR-363 in chemoresistance of the ovarian cancer. qRT-PCR indicated that miR-363 was upregulated in KF-TX cells, confirming the array data, and introduction of miR-363 into sensitive ovarian cancer cells confers TX-resistance and significantly inhibited the expression of the Hippo member, LATS2, as indicated by viability, clonogenic assays and expression analysis. Furthermore, we validated the role of LATS2 in the TX-response by sh-based silencing, which also confers TX-resistance in the responsive ovarian cancer cells. On the other hand, specific inhibitor against miR-363 restored the response to TX. In addition, miR-363 was found to bind to the 3′-UTR of LATS2 mRNA, confirming that miR-363 directly targets LATS2 as indicated by dual luciferase assay. RT-PCR-based evaluation of miR-363 in a panel of human ovarian tumours revealed its upregulation in most of the tumour tissues identified as resistant while downregulation of the same gene in most of the tissues identified as sensitive ones. Moreover, higher levels of miR-363 in human ovarian cancer specimens were significantly correlated with TX chemoresistance and poor prognosis. Taken together, our study reveals the involvement of miR-363 in chemoresistance by targeting LATS2 in ovarian cancers, raising the possibility that combination therapy with a miR-363 inhibitor and TX may increase TX efficacy and reduce the chance of TX-resistance.
Note: This abstract was not presented at the meeting.
Citation Format: Noriaki Sakuragi, Mohamed Kamel Farah, Zeinab Mohamed, Safwat Okasha, Hidemichi Watari, Takashi Mitamura, sherif El Khamisy, Yusuke Ohba. Comparative miRNA microarray profiling indicates miR-363 promotes chemoresistance in ovarian cancer cells by targeting the Hippo member, LATS2 [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-323. doi:10.1158/1538-7445.AM2017-LB-323
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Sugar-sweetened beverage intake and its associations with cardiometabolic risks among adolescents. Pediatr Obes 2017; 12:e1-e5. [PMID: 26843446 DOI: 10.1111/ijpo.12108] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 11/19/2015] [Accepted: 12/18/2015] [Indexed: 10/22/2022]
Abstract
BACKGROUND Investigations on sugar-sweetened beverage (SSB) intake and cardiometabolic risks among Asians are scant. OBJECTIVES This study aimed to examine associations between SSB intake and cardiometabolic risks among Malaysian adolescents. METHODS Anthropometric data, blood pressure (BP), fasting blood glucose (FBG), lipid profiles and insulin levels measured involved 873 adolescents (aged 13 years). SSB intake, dietary patterns and physical activity level (PAL) were self-reported. RESULTS Mean SSB consumption was 177.5 mL day-1 with significant differences among ethnicities (Malay, Chinese, Indians and Others) (p < 0.05). SSB intake was deleteriously associated with increased waist circumference, elevated triglycerides, FBG, insulin, insulin resistance and low HDL-cholesterol, independent of PAL, body mass index and dietary patterns. Significant U-shaped and inverse trends were noted between SSB intake and LDL-cholesterol and BP, respectively. CONCLUSION Sugar-sweetened beverage intake was unfavourably associated with cardiometabolic health outcomes among young adolescents. Concerted efforts towards healthy hydration are imperative to mitigate risk of cardiometabolic events.
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Incidence of mycobiota in some dairy products and its public health hazards. ALEXANDRIA JOURNAL OF VETERINARY SCIENCES 2017. [DOI: 10.5455/ajvs.220588] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Influence of Film Thickness and Annealing Temperature on Optical Properties of Nanostructured-TiO2 Thin Films Prepared by Sol–Gel Spin Coating Technique. INTERNATIONAL JOURNAL OF NANOSCIENCE 2016. [DOI: 10.1142/s0219581x16500289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
TiO2 powder was found to be polycrystalline with rutile system. TiO2 films were deposited on quartz substrates by a sol–gel spin coating technique. X-ray diffraction and transmission electron microscope results have confirmed that the TiO2 films have nanostructure nature. It is found the crystallite size increased with annealing temperature. The optical constants of nanostructured TiO2 films were found to be independent of film thickness in the range from 100[Formula: see text]nm to 500[Formula: see text]nm. It is found that the optical constants and the dielectric constant of the thin films were all affected by annealing temperature. The existing allowed optical transitions in the as-deposited and annealed films were found to be direct and indirect transitions. Finally, the bandgaps of the as-deposited film were found to decrease with the annealing temperature.
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Seroprevalence of Toxoplasma gondii infection among patients in Hospital Universiti Sains Malaysia. Trop Biomed 2016; 33:78-83. [PMID: 33579143] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Toxoplasmosis is a worldwide endemic zoonotic infection caused by the obligate coccidian parasite Toxoplasma gondii. To assess the seroprevalence of T. gondii infection among hospital population of Hospital Universiti Sains Malaysia (HUSM), a cross-sectional study was conducted using serum samples of 102 participants. Samples were screened for the presence of anti-Toxoplasma IgG and IgM antibodies by enzyme-linked immunosorbent assay (ELISA). Only one sample recorded as IgM positive (0.98%) (1/102; 95% CI = 0.02- 5.34%), whereas 44.12% (45/102; 95% CI = 34.29-54.29%) were IgG positive. The study showed that seroprevalence of toxoplasmosis significantly differs between age groups (p < 0.001), with high prevalence of T. gondii infection (37.8%) among patients aged less than one month. Moreover, the study indicated a significant difference in the prevalence of toxoplasmosis between males and females. Additionally, a significant dependent relationships were observed (p = 0.003), when the reasons of toxoplasma serology request was considered, and the highest prevalence (59.6%) observed in congenital toxoplasmosis. In conclusion, the seroprevalence of toxoplasmosis in our study group was high. The study provides preliminary information about the seroprevalence and epidemiology of T. gondii infection among the hospital population in HUSM.
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Conventional versus Doxorubicin-Eluting Beads Transarterial Chemoembolization for Unresectable Hepatocellular Carcinoma: a Tertiary Medical Centre Experience in Malaysia. Asian Pac J Cancer Prev 2016; 17:4037-4041. [PMID: 27644658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023] Open
Abstract
BACKGROUND Hepatocellular carcinoma (HCC) is a common cancer that is frequently diagnosed at an advanced stage. Transarterial chemoembolisation (TACE) is an effective palliative treatment for patients who are not eligible for curative treatment. The two main methods for performing TACE are conventional (c-TACE) or with drug eluting beads (DEB-TACE). We sought to compare survival rates and tumour response between patients undergoing c-TACE and DEB-TACE at our centre. MATERIALS AND METHODS A retrospective cohort study of patients undergoing either treatment was carried out from January 2009 to December 2014. Tumour response to the procedures was evaluated according to the modified Response Evaluation Criteria in Solid Tumors (mRECIST). Kaplan-Meier analysis was used to assess and compare the overall survival in the two groups. RESULTS A total of 79 patients were analysed (34 had c-TACE, 45 had DEB-TACE) with a median follow-up of 11.8 months. A total of 20 patients in the c-TACE group (80%) and 12 patients in the DEB-TACE group (44%) died during the follow up period. The median survival durations in the c-TACE and DEB-TACE groups were 4.9 ± 3.2 months and 8.3 ± 2.0 months respectively (p=0.008). There was no statistically significant difference noted among the two groups with respect to mRECIST criteria. CONCLUSIONS DEB-TACE demonstrated a significant improvement in overall survival rates for patients with unresectable HCC when compared to c-TACE. It is a safe and promising approach and should potentially be considered as a standard of care in the management of unresectable HCC.
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Disparities in health-related quality of life among healthy adolescents in a developing country - the impact of gender, ethnicity, socio-economic status and weight status. Child Care Health Dev 2015; 41:1216-26. [PMID: 25873448 DOI: 10.1111/cch.12252] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/15/2015] [Indexed: 11/27/2022]
Abstract
BACKGROUND Physical functioning and psychological resilience in adulthood is shaped during adolescence. Self-reported health-related quality of life (HRQoL) assessments during this life phase are important first-hand accounts of their well-being. This study aimed, firstly, to identify differences in HRQoL according to gender, ethnicity, socio-economic status and weight status; and secondly, to examine associations between weight status and HRQoL among an urban sample of multi-ethnic adolescents in Kuala Lumpur, Malaysia. METHODS A cross-sectional study involving 652 adolescents (aged 13 years) was conducted in Kuala Lumpur. Weight and height were measured. Body mass index z-scores were categorized according to the International Obesity Task Force criteria. HRQoL was assessed using the Malay version of the Pediatric Quality of Life Inventory 4.0 Generic Core Scales. Univariate analyses of differences in HRQoL according to gender, ethnicity (Malays, Chinese and Indians), maternal education level and weight status were performed. Complex samples general linear model was used to examine the associations between HRQoL and weight status, adjusted for confounders. RESULTS Female adolescents reported significantly lower emotional functioning scores (mean, 95% confidence interval: 59.25, 57.33-61.17). When the three main ethnic groups were studied, Malay adolescents scored significantly lower emotional functioning scores (59.00, 57.13-60.87) compared with their Chinese peers. Adolescents with tertiary-educated mothers reported lower emotional functioning scores (57.45, 53.85-61.06) compared with those with primary-educated mothers. Obese adolescents reported poorer HRQoL scores with significantly impaired physical and social functioning after controlling for confounders. CONCLUSIONS These findings detected disparities in HRQoL among the adolescents when gender, ethnicity, maternal education level and weight status were considered. Further studies should address these health inequalities by implementing gender-specific and culturally appropriate measures to attain optimal well-being and avoid potential burden of disease.
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Hepatic Pseudoaneurysms from Motor Vehicle Accidents Treated with Endovascular Embolisations. HONG KONG JOURNAL OF RADIOLOGY 2014. [DOI: 10.12809/hkjr1413196] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
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P0177 Impact of genetic polymorphisms of MTHFR, SLC, and ABC on high-dose methotrexate toxicity and plasma levels in adults with haematological malignancies. Eur J Cancer 2014. [DOI: 10.1016/j.ejca.2014.03.221] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Vitamin D status and parathyroid hormone concentrations influence the skeletal response to zoledronate and denosumab. Calcif Tissue Int 2014; 94:553-9. [PMID: 24509506 DOI: 10.1007/s00223-014-9840-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 11/24/2013] [Indexed: 12/01/2022]
Abstract
Studies suggest that optimal vitamin D status is required for the maximal effect of antiresorptive agents. We investigated the relationship between vitamin D status, serum parathyroid hormone (PTH) concentrations, and change in bone mineral density (BMD) following iv zoledronate and denosumab. We carried out a retrospective analysis of 111 patients, mean age 70 (SD 13) years, 89 women and 22 men, prescribed zoledronate and 43 postmenopausal women treated with denosumab for osteoporosis. We measured BMD at the lumbar spine (LS) and total hip (TH), serum 25 (OH) vitamin D, PTH, and bone turnover markers (plasma CTX, P1NP) at 1 year. In patients on zoledronate, BMD increased at the LS and TH (mean LS change [SEM] = 2.6 % [0.5 %], mean TH change = 1.05 % [0.5 %], p < 0.05). A significant increase in BMD was seen at the LS only in the denosumab group (p = 0.001). Significant decreases in CTX and P1NP were observed at 12 months in both treatment groups. At baseline and at 12 months, 34 % and 23 % of the patients on zoledronate had a serum vitamin D of <50 nmol/L, respectively. The mean PTH concentration in patients with 25 (OH) vitamin D <50 nmol/L was 44 ng/L (SEM 16.6). Patients with PTH concentration <44 ng/L had significantly higher increases in TH BMD compared to those with PTH >44 ng/L (zoledronate 1.9 [0.83] vs. -0.43 [0.81], p = 0.04; denosumab 4.1 [0.054] vs. -1.7 [0.04], p = 0.004). Optimal vitamin D status and PTH concentrations improve the skeletal response to zoledronate and denosumab.
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RESPONSE OF FABA BEAN PLANTS TO APPLICATION OF SOME GROWTH PROMOTERS UNDER SALINITY STRESS CONDITIONS. ACTA ACUST UNITED AC 2014. [DOI: 10.21608/jpp.2014.53482] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Genetic associations of the INSIG2 rs7566605 polymorphism with obesity-related metabolic traits in Malaysian Malays. GENETICS AND MOLECULAR RESEARCH 2014; 13:4904-10. [DOI: 10.4238/2014.july.4.4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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G2677T polymorphism can predict treatment outcome of Malaysians with complex partial seizures being treated with Carbamazepine. GENETICS AND MOLECULAR RESEARCH 2013; 12:5937-44. [PMID: 24338387 DOI: 10.4238/2013.november.26.3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Carbamazepine (CBZ) is used as the first line of treatment of complex partial seizures (CPS) in Malaysia. While this drug is known to be effective for the treatment of CPS, more than 30% of patients remain drug resistant to CBZ mono-therapy. We examined a possible relationship between patients' response to CBZ mono-therapy and the G2677T SNP of the ABCB1 gene. Three hundred and fourteen patients with CPS were recruited from the Neurology Department of the Kuala Lumpur Hospital, of whom 152 were responders and the other 162 were non-responders to CBZ mono-therapy. DNA was extracted from blood samples and real-time PCR was performed to detect the G2677T SNP of the ABCB1 gene. Results were described as genotype frequencies and compared by logistic regression analysis. Among the 152 responders, 74% had the GG genotype. However, among the 162 non-responders, 26.5% had the GT genotype and 39% had the TT genotype. There was a significant difference in genotype frequency (TT vs GG; odds ratio 4.70; 95% confidence interval, 2.70-8.20) between responders and non-responders. The presence of the T allele of the G2677T SNP appears to be a useful screening marker to determine if a patient is going to be resistant to CBZ as a single drug therapy in the treatment of CPS.
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Protein expression in sera of patients with amoebic liver abscess (ALA): potential use of haptoglobin as a surrogate disease marker. Trop Biomed 2013; 30:257-266. [PMID: 23959491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The protein profile of serum samples from patients with amoebic liver abscess (ALA) was compared to those of normal individuals to determine their expression levels and to identify potential surrogate disease markers. Serum samples were resolved by two dimensional electrophoresis (2-DE) followed by image analysis. The up and down-regulated protein spots were excised from the gels and analysed by MS/MS. The concentration of three clusters of proteins i.e. haptoglobin (HP), α1-antitrypsin (AAT) and transferrin in serum samples of ALA patients and healthy controls were compared using competitive ELISA. In addition, serum concentrations of HP and transferrin in samples of patients with ALA and pyogenic liver abscess (PLA) were also compared. The results of the protein 2-DE expression analysis showed that HP cluster, AAT cluster, one spot each from unknown spots no. 1 and 2 were significantly up-regulated and transferrin cluster was significantly down-regulated in ALA patients' sera (p<0.05). The MS/MS analysis identified the unknown protein spot no.1 as human transcript and haptoglobin and spot no. 2 as albumin. Competitive ELISA which compared concentrations of selected proteins in sera of ALA and healthy controls verified the up-regulated expression (p<0.05) of HP and the down-regulated expression (p<0.01) of transferrin in the former, while there was no significant difference in AAT expression (p> 0.05). However, when ALA and PLA samples were compared, competitive ELISA showed significant increased concentration of HP (p<0.05) while transferrin levels were not different. In conclusion, this study showed that HP is a potential surrogate disease marker for ALA.
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Novel Inflammation-Based Prognostic Determinants in Patients with Carcinoma of Unknown Primary. Ann Oncol 2012. [DOI: 10.1016/s0923-7534(20)33722-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Detection of selected intestinal helminths and protozoa at Hospital Universiti Sains Malaysia using multiplex real-time PCR. Trop Biomed 2012; 29:434-442. [PMID: 23018507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Intestinal parasites are the causative agents of a number of important human infections in developing countries. The objective of this study was to determine the prevalence of selected helminths and protozoan infections among patients admitted with gastrointestinal disorders at Hospital Universiti Sains Malaysia, Kelantan, Malaysia using multiplex real-time PCR. In addition microscopic examination was also performed following direct smear, zinc sulphate concentration and Kato-Katz thick smear techniques; and the presence of protozoan parasites was confirmed using trichrome and acid-fast stains. Of the 225 faecal samples analysed, 26.2% were positive for intestinal parasites by the multiplex real-time PCR, while 5.3% were positive by microscopy. As compared to microscopy, the multiplex real-time PCR detected 5.8 and 4.5 times more positives for the selected helminth and protozoan infections respectively. Among the selected helminths detected in this study, hookworm was the most prevalent by real-time PCR, while Ascaris lumbricoides was detected the most by microscopy. Meanwhile, among the selected protozoa detected in this study, Entamoeba histolytica was the most prevalent by real-time PCR, however microscopy detected equal number of cases with E. histolytica and Giardia lamblia. This study showed that real-time PCR can be used to obtain a more accurate prevalence data on intestinal helminths and protozoa.
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Genetic association of SNPs in the FTO gene and predisposition to obesity in Malaysian Malays. Braz J Med Biol Res 2012; 45:1119-26. [PMID: 22911346 PMCID: PMC3854209 DOI: 10.1590/s0100-879x2012007500134] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Accepted: 08/09/2012] [Indexed: 12/18/2022] Open
Abstract
The common variants in the fat mass- and obesity-associated (FTO) gene have been previously found to be associated with obesity in various adult populations. The objective of the present study was to investigate whether the single nucleotide polymorphisms (SNPs) and linkage disequilibrium (LD) blocks in various regions of the FTO gene are associated with predisposition to obesity in Malaysian Malays. Thirty-one FTO SNPs were genotyped in 587 (158 obese and 429 non-obese) Malaysian Malay subjects. Obesity traits and lipid profiles were measured and single-marker association testing, LD testing, and haplotype association analysis were performed. LD analysis of the FTO SNPs revealed the presence of 57 regions with complete LD (D' = 1.0). In addition, we detected the association of rs17817288 with low-density lipoprotein cholesterol. The FTO gene may therefore be involved in lipid metabolism in Malaysian Malays. Two haplotype blocks were present in this region of the FTO gene, but no particular haplotype was found to be significantly associated with an increased risk of obesity in Malaysian Malays.
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Transplantation - basic. Nephrol Dial Transplant 2012. [DOI: 10.1093/ndt/gfs247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Lack of association of ABCB1 and PXR polymorphisms with response to treatment in epilepsy. Seizure 2011; 20:387-94. [PMID: 21316268 DOI: 10.1016/j.seizure.2011.01.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2010] [Revised: 01/10/2011] [Accepted: 01/17/2011] [Indexed: 01/08/2023] Open
Abstract
It is proposed that overexpression of P-glycoprotein (P-gp), encoded by the ABC subfamily B member 1 (ABCB1) gene, is involved in resistance to antiepileptic drugs (AEDs) in about 30% of patients with epilepsy. Genetic variation and haplotype patterns are population specific which may cause different phenotypes such as response to AEDs. Although several studies examined the link between the common polymorphisms in the ABCB1 gene with resistance to AEDs, the results have been conflicting. This controversy may be caused by the effect of some confounders such as ethnicity and polytherapy. Moreover, expression of the ABCB1 gene is under the control of pregnane X receptor (PXR). Evidence showed that PXR gene contribute to the response to treatment. The aim of this study was to assess the association of ABCB1 and PXR genetic polymorphisms with response to the carbamazepine (CBZ) or sodium valproate (VPA) monotherapy in epilepsy. Genotypes were assessed in 685 Chinese, Indian, and Malay epilepsy patients for ABCB1 (C1236T, G2677T, C3435T) and PXR (G7635A) polymorphisms. No association between these polymorphisms and their haplotypes, and interaction between them, with response to treatment was observed in the overall group or in the Chinese, Indian, and Malay subgroups. Our data showed that these polymorphisms may not contribute to the response to CBZ or VPA monotherapy treatment in epilepsy.
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Analysis of Captopril in Human Plasma Using Gas Chromatography-Mass Spectrometry (GCMS) with Solid-Phase Extraction (SPE). CURR ANAL CHEM 2010. [DOI: 10.2174/1573411011006040329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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A new record of Iranihindia martellata (Senior-White,1924) (Diptera: Sarcophagidae) from peninsular Malaysia and female identification using both morphology and DNA-based approaches. Trop Biomed 2010; 27:287-293. [PMID: 20962727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Iranihindia martellata (Senior-White, 1924) is recorded from peninsular Malaysia for the first time. Male and female specimens in the recent collections of forensically important sarcophagid flies were examined and identified based on morphology and DNA sequencing analysis. Male genitalia offer unambiguous species identification characteristics in the traditional taxonomy of flesh flies but the female flies are very similar to one another in general morphology. Female of I. martellata was determined by DNA sequencing (COI and COII) and PCR-RFLP (COI) analysis. Identified females were carefully examined and compared with the morphologically similar species, Liopygia ruficornis (Fabricius, 1794). Female genitalia are re-described and illustrated in this paper.
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ABCB1 C3435T polymorphism and the risk of resistance to antiepileptic drugs in epilepsy: a systematic review and meta-analysis. Seizure 2010; 19:339-46. [PMID: 20605481 DOI: 10.1016/j.seizure.2010.05.004] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2010] [Revised: 04/30/2010] [Accepted: 05/07/2010] [Indexed: 01/16/2023] Open
Abstract
OBJECTIVE The C3435T, a major allelic variant of the ABCB1 gene, is proposed to play a crucial role in drug-resistance in epilepsy. The C/C genotype carriers reportedly are at higher risk of pharmacoresistance to AEDs, but only in some studies. The hypothesis of the C-variant associated risk and resistance to antiepileptic drugs (AEDs) has been hampered by conflicting results from inadequate power in case-control studies. To assess the role of C3435T polymorphism in drug-resistance in epilepsy, a systematic review and meta-analysis was conducted. METHODS Databases were obtained from the Cochrane Library, MEDLINE, EMBASE, major American and European conference abstracts, and www.google.my for genetic association studies up to February 2010. All the case-control association studies evaluating the role of ABCB1 C3435T in pharmacoresistance to AEDs were identified. The new definition of treatment outcome from International League Against Epilepsy (ILAE) was used for including studies for sub-analysis. To measure the strength of genetic association for the gene variant, the odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using models of both fixed- and random-effects for comparisons of the alleles and genotypes with co-dominant (C/C vs. T/T, C/T vs. T/T), dominant (C/C+C/T vs. T/T), and recessive (C/C vs. C/T+T/T) models in overall and in ethnicity subgroups. The 19 studies were selected for the next sub-analysis based on the new definition of drug-responsiveness and drug-resistance from ILAE. The same analysis was also performed for treatment outcome and ethnicity subgroups. RESULTS A total of 22 association studies including 3231 (47.8%) drug-resistant patients and 3524 (52.2%) drug-responsive patients or healthy controls (genotyped for C3435T) were pooled in this meta-analysis. The allelic association of ABCB1 C3435T with risk of drug-resistance was not significant under fixed-effects model, 1.06 (95% CI 0.98-1.14, p=0.12) and random-effects model, 1.10 (0.93-1.30, p=0.28) in overall and in the subgroup analysis by ethnicity. Similar results were also obtained for all genetic models in the stratified analyses by new definition of drug-resistance by ILAE and ethnicity subgroups. There was no publication bias. CONCLUSION We failed to show an association between the ABCB1 C3435T polymorphism and the risk of drug-resistance suggesting a revision in contribution of this polymorphism in the multi-drug transporters hypothesis of pharmacoresistance to AEDs in epilepsy.
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Association of ABCB1 and NR1I2 polymorphisms with response to carbamazepine in Malaysian epilepsy patients. FASEB J 2010. [DOI: 10.1096/fasebj.24.1_supplement.756.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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