Displaying publications 61 - 80 of 4456 in total

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  1. A critical role of TRPM2 channel in Aβ42 -induced microglial activation and generation of tumor necrosis factor-α
    Alawieyah Syed Mortadza S, Sim JA, Neubrand VE, Jiang LH
    Glia, 2018 03;66(3):562-575.
    PMID: 29143372 DOI: 10.1002/glia.23265
    Amyloid β (Aβ)-induced neuroinflammation plays an important part in Alzheimer's disease (AD). Emerging evidence supports a role for the transient receptor potential melastatin-related 2 (TRPM2) channel in Aβ-induced neuroinflammation, but how Aβ induces TRPM2 channel activation and this relates to neuroinflammation remained poorly understood. We investigated the mechanisms by which Aβ42 activates the TRPM2 channel in microglial cells and the relationships to microglial activation and generation of tumor necrosis factor-α (TNF-α), a key cytokine implicated in AD. Exposure to 10-300 nM Aβ42 induced concentration-dependent microglial activation and generation of TNF-α that were ablated by genetically deleting (TRPM2 knockout ;TRPM2-KO) or pharmacologically inhibiting the TRPM2 channel, revealing a critical role of this channel in Aβ42 -induced microglial activation and generation of TNF-α. Mechanistically, Aβ42 activated the TRPM2 channel via stimulating generation of reactive oxygen species (ROS) and activation of poly(ADPR) polymerase-1 (PARP-1). Aβ42 -induced generation of ROS and activation of PARP-1 and TRPM2 channel were suppressed by inhibiting protein kinase C (PKC) and NADPH oxidases (NOX). Aβ42 -induced activation of PARP-1 and TRPM2 channel was also reduced by inhibiting PYK2 and MEK/ERK. Aβ42 -induced activation of PARP-1 was attenuated by TRPM2-KO and moreover, the remaining PARP-1 activity was eliminated by inhibiting PKC and NOX, but not PYK2 and MEK/ERK. Collectively, our results suggest that PKC/NOX-mediated generation of ROS and subsequent activation of PARP-1 play a role in Aβ42 -induced TRPM2 channel activation and TRPM2-dependent activation of the PYK2/MEK/ERK signalling pathway acts as a positive feedback to further facilitate activation of PARP-1 and TRPM2 channel. These findings provide novel insights into the mechanisms underlying Aβ-induced AD-related neuroinflammation.
    Matched MeSH terms: MAP Kinase Signaling System/physiology
  2. Fulltext A deformable generic 3D model of haptoral anchor of Monogenean
    Teo BG, Dhillon SK, Lim LH
    PLoS One, 2013;8(10):e77650.
    PMID: 24204903 DOI: 10.1371/journal.pone.0077650
    In this paper, a digital 3D model which allows for visualisation in three dimensions and interactive manipulation is explored as a tool to help us understand the structural morphology and elucidate the functions of morphological structures of fragile microorganisms which defy live studies. We developed a deformable generic 3D model of haptoral anchor of dactylogyridean monogeneans that can subsequently be deformed into different desired anchor shapes by using direct manipulation deformation technique. We used point primitives to construct the rectangular building blocks to develop our deformable 3D model. Point primitives are manually marked on a 2D illustration of an anchor on a Cartesian graph paper and a set of Cartesian coordinates for each point primitive is manually extracted from the graph paper. A Python script is then written in Blender to construct 3D rectangular building blocks based on the Cartesian coordinates. The rectangular building blocks are stacked on top or by the side of each other following their respective Cartesian coordinates of point primitive. More point primitives are added at the sites in the 3D model where more structural variations are likely to occur, in order to generate complex anchor structures. We used Catmull-Clark subdivision surface modifier to smoothen the surface and edge of the generic 3D model to obtain a smoother and more natural 3D shape and antialiasing option to reduce the jagged edges of the 3D model. This deformable generic 3D model can be deformed into different desired 3D anchor shapes through direct manipulation deformation technique by aligning the vertices (pilot points) of the newly developed deformable generic 3D model onto the 2D illustrations of the desired shapes and moving the vertices until the desire 3D shapes are formed. In this generic 3D model all the vertices present are deployed for displacement during deformation.
    Matched MeSH terms: Fishes/physiology*
  3. A demonstration of the use of the polygraph to record Schultz-Dale reactions utilizing sera of monkeys infected with Brugia malayi as sources of both antibody and antigen
    Guest MF, Kek CL, Wong MM, Cheong LK
    Med J Malaya, 1966 Jun;20(4):325-6.
    PMID: 4224346
    Matched MeSH terms: Muscle Contraction/physiology*
  4. A description of a pleurolophocercous cercaria of Procerovum sp from the Haplorchis group of heterophyid trematodes
    Surin J
    Southeast Asian J. Trop. Med. Public Health, 1993 Dec;24(4):692-6.
    PMID: 7939942
    Freshwater snails, Stenomelania denisoniensis (Brot) from Tinaroo Dam, North Queensland, Australia were found to be infected with a heterophyid cercaria identified as Procerovum sp. The tail of the cercaria has finfolds which are bilateral anteriorly and dorso-ventral posteriorly, features which separate it from other genera in the Haplorchis-group. This group is differentiated from the cercariae of all the other heterophyid genera by the presence of the penetration glands that extend to the posterior end of the body lateral to the excretory bladder. This paper presents a full description of the cercaria, together with comparisons with other known species of Procerovum.
    Matched MeSH terms: Trematoda/physiology*
  5. A device to facilitate preparation of high-density neural cell cultures in MEAs
    Mok SY, Lim YM, Goh SY
    J Neurosci Methods, 2009 May 15;179(2):284-91.
    PMID: 19428539 DOI: 10.1016/j.jneumeth.2009.02.009
    A device to facilitate high-density seeding of dissociated neural cells on planar multi-electrode arrays (MEAs) is presented in this paper. The device comprises a metal cover with two concentric cylinders-the outer cylinder fits tightly on to the external diameter of a MEA to hold it in place and an inner cylinder holds a central glass tube for introducing a cell suspension over the electrode area of the MEA. An O-ring is placed at the bottom of the inner cylinder and the glass tube to provide a fluid-tight seal between the glass tube and the MEA electrode surface. The volume of cell suspension in the glass tube is varied according to the desired plating density. After plating, the device can be lifted from the MEA without leaving any residue on the contact surface. The device has enabled us to increase and control the plating density of neural cell suspension with low viability, and to prepare successful primary cultures from cryopreserved neurons and glia. The cultures of cryopreserved dissociated cortical neurons that we have grown in this manner remained spontaneously active over months, exhibited stable development and similar network characteristics as reported by other researchers.
    Matched MeSH terms: Action Potentials/physiology; Cell Survival/physiology; Electrophysiology/instrumentation*; Electrophysiology/methods; Nerve Net/physiology; Neuroglia/physiology; Neurons/physiology*; Neurophysiology/instrumentation*; Neurophysiology/methods
  6. A feasibility study on preoperative carbohydrate loading in older patients undergoing hip fracture surgery
    Yap KS, Loh PS, Foong YX, Mok CZ, Ong T, Khor HM
    BMC Geriatr, 2024 May 06;24(1):401.
    PMID: 38711010 DOI: 10.1186/s12877-024-04958-7
    BACKGROUND: Preoperative carbohydrate loading in Enhanced Recovery After Surgery is an independent predictor of postoperative outcomes. By reducing the impact of surgical stress response, fasting-induced insulin resistance is modulated. As a clear fluid, consuming carbohydrate drink is safe up to 2 h preoperatively. Widely practiced in abdominal surgeries, its implementation in hip fracture surgeries is yet to be recognized. This study aimed to identify the feasibility of preoperative carbohydrate loading in hip fracture surgery and assess its clinical effects.

    METHODS: This was a randomized controlled, open labelled trial. Patients ≥ 65 years old without diabetes mellitus, has hip fracture were recruited in a tertiary hospital between November 2020 and May 2021. The intervention was carbohydrate loading versus standard preoperative fasting.

    RESULTS: Thirty-four ASA I-III patients (carbohydrate loading and control, n = 17 each), mean age 78 years (SEM ± 1.5), mean body mass index 23.7 (SEM ± 0.6 kg/m2) were recruited. Analysis for feasibility of carbohydrate loading (n = 17) demonstrated attrition rate of 29% (n = 5). Otherwise, all recruited patients were compliant (100% compliance) with no adverse events reported. There was no significant difference among groups in the postoperative nausea and vomiting, pain score, fatigue level, muscle strength, postoperative infection and length of hospital stay assessed at 24-48 h postoperatively.

    CONCLUSION: The implementation of preoperative carbohydrate loading was found to be feasible preoperatively in hip fracture surgeries but requires careful coordination among multidisciplinary teams. An adequately powered randomized controlled study is needed to examine the full benefits of preoperative carbohydrate loading in this group of patients.

    TRIAL REGISTRATION: This study was registered in ClinicalTrial.gov (ClinicalTrials.gov identifier: NCT04614181, date of registration: 03/11/2020).

    Matched MeSH terms: Fasting/physiology
  7. A field and laboratory study of the responses of cytoprotection and osmoregulation to salinity stress in mosquitofish (Gambusia affinis)
    Tsai JW, Liew HJ, Jhang JJ, Hung SH, Meng PJ, Leu MY, et al.
    Fish Physiol Biochem, 2018 Apr;44(2):489-502.
    PMID: 29192359 DOI: 10.1007/s10695-017-0448-y
    The mosquitofish (Gambusia affinis) naturally inhabits freshwater (FW; 1-3‰) and seawater (SW; 28-33‰) ponds in constructed wetland. To explore the physiological status and molecular mechanisms for salinity adaptation of the mosquitofish, cytoprotective responses and osmoregulation were examined. In the field study, activation of protein quality control (PQC) mechanism through upregulation of the abundance of heat shock protein (HSP) 90 and 70 and ubiquitin-conjugated proteins was found in the mosquitofish gills from SW pond compared to the individuals of FW pond. The levels of aggregated proteins in mosquitofish gills had no significant difference between FW and SW ponds. Furthermore, the osmoregulatory responses revealed that the body fluid osmolality and muscle water contents of the mosquitofish from two ponds were maintained within a physiological range while branchial Na+/K+-ATPase (NKA) expression was higher in the individuals from SW than FW ponds. Subsequently, to further clarify whether the cellular stress responses and osmoregulation were mainly induced by hypertonicity, a laboratory salinity acclimation experiment was conducted. The results from the laboratory experiment were similar to the field study. Branchial PQC as well as NKA responses were induced by SW acclimation compared to FW-acclimated individuals. Taken together, induction of gill PQC and NKA responses implied that SW represents an osmotic stress for mosquitofish. Activation of PQC was suggested to provide an osmoprotection to prevent the accumulation of aggregated proteins. Moreover, an increase in branchial NKA responses for osmoregulatory adjustment was required for the physiological homeostasis of body fluid osmolality and muscle water content.
    Matched MeSH terms: Cyprinodontiformes/physiology*; Gills/physiology
  8. A fluid mechanical explanation of the spontaneous reattachment of a previously detached Descemet membrane
    Ismail Z, Fitt AD, Please CP
    Math Med Biol, 2013 Dec;30(4):339-55.
    PMID: 23054933 DOI: 10.1093/imammb/dqs028
    Descemet membrane detachment (DMD) is a rare but potentially serious surgical complication that arises most often during cataract surgery. A recent study (Couch, S. M. & Baratz, K. H. (2009) Cornea, 28, 1160-1163) cited the case of a patient with DMDs in both eyes, noting that though one detachment was surgically repaired, the other spontaneously reattached and needed no further treatment. A fluid mechanical model of buoyancy-driven aqueous humour flow in the anterior chamber around a DMD is developed to explain this phenomenon. The analytical model is based on the lubrication theory limit of the Navier-Stokes equations. The flow is determined for a fixed geometry and the possible motion of the DMD is then analysed. Numerical calculations are also carried out (using COMSOL© Multiphysics) to confirm the lubrication theory results. The analytical and numerical results both show that, under the correct conditions, either spontaneous reattachment or worsening of the tear may occur. We conclude that it is possible that clinical outcomes for DMDs may be controlled by adjusting the temperature difference across the eye and/or the orientation of the patient.
    Matched MeSH terms: Aqueous Humor/physiology*
  9. Fulltext A fuzzy controller for lower limb exoskeletons during sit-to-stand and stand-to-sit movement using wearable sensors
    Reza SM, Ahmad N, Choudhury IA, Ghazilla RA
    Sensors (Basel), 2014 Mar 04;14(3):4342-63.
    PMID: 24599193 DOI: 10.3390/s140304342
    Human motion is a daily and rhythmic activity. The exoskeleton concept is a very positive scientific approach for human rehabilitation in case of lower limb impairment. Although the exoskeleton shows potential, it is not yet applied extensively in clinical rehabilitation. In this research, a fuzzy based control algorithm is proposed for lower limb exoskeletons during sit-to-stand and stand-to-sit movements. Surface electromyograms (EMGs) are acquired from the vastus lateralis muscle using a wearable EMG sensor. The resultant acceleration angle along the z-axis is determined from a kinematics sensor. Twenty volunteers were chosen to perform the experiments. The whole experiment was accomplished in two phases. In the first phase, acceleration angles and EMG data were acquired from the volunteers during both sit-to-stand and stand-to-sit motions. During sit-to-stand movements, the average acceleration angle at activation was 11°-48° and the EMG varied from -0.19 mV to +0.19 mV. On the other hand, during stand-to-sit movements, the average acceleration angle was found to be 57.5°-108° at the activation point and the EMG varied from -0.32 mV to +0.32 mV. In the second phase, a fuzzy controller was designed from the experimental data. The controller was tested and validated with both offline and real time data using LabVIEW.
    Matched MeSH terms: Movement/physiology*; Posture/physiology*; Muscle, Skeletal/physiology; Lower Extremity/physiology*
  10. A fuzzy integral method based on the ensemble of neural networks to analyze fMRI data for cognitive state classification across multiple subjects
    Cacha LA, Parida S, Dehuri S, Cho SB, Poznanski RR
    J Integr Neurosci, 2016 Dec;15(4):593-606.
    PMID: 28093025 DOI: 10.1142/S0219635216500345
    The huge number of voxels in fMRI over time poses a major challenge to for effective analysis. Fast, accurate, and reliable classifiers are required for estimating the decoding accuracy of brain activities. Although machine-learning classifiers seem promising, individual classifiers have their own limitations. To address this limitation, the present paper proposes a method based on the ensemble of neural networks to analyze fMRI data for cognitive state classification for application across multiple subjects. Similarly, the fuzzy integral (FI) approach has been employed as an efficient tool for combining different classifiers. The FI approach led to the development of a classifiers ensemble technique that performs better than any of the single classifier by reducing the misclassification, the bias, and the variance. The proposed method successfully classified the different cognitive states for multiple subjects with high accuracy of classification. Comparison of the performance improvement, while applying ensemble neural networks method, vs. that of the individual neural network strongly points toward the usefulness of the proposed method.
    Matched MeSH terms: Brain/physiology*; Cognition/physiology*; Visual Perception/physiology
  11. A gelatinized lipopeptide diet effectively modulates immune response, disease resistance and gut microbiome in Penaeus vannamei challenged with Vibrio parahaemolyticus
    Prathiviraj R, Rajeev R, Fernandes H, Rathna K, Lipton AN, Selvin J, et al.
    Fish Shellfish Immunol, 2021 May;112:92-107.
    PMID: 33675990 DOI: 10.1016/j.fsi.2021.02.018
    Penaeus vannamei is one of the most economically vital shrimp globally, but infectious diseases have hampered its proper production and supply. As antibiotics pose a huge threat to the environment and humankind, it is essential to seek an alternative strategy to overcome infection and ensure proper culture and production. The present study investigates the effect of an anti-infective biosurfactant derivative lipopeptide MSA31 produced by a marine bacterium on the growth performance, disease resistance, and the gut microbiome of P. vannamei when challenged with pathogenic Vibrio parahaemolyticus SF14. The shrimp were fed with a commercial and lipopeptide formulated diet for 60 days and the growth performance was analyzed. The lipopeptide fed shrimp group showed enhanced growth performance and specific growth rate with improved weight gain than the control group. The challenge experiment showed that the survival rate was significant in the lipopeptide fed group compared to the control group. The results revealed 100% mortality in the control group at the end of 12 h of challenge, while 50% of the lipopeptide diet-fed group survived 24 h, which indicates the enhanced disease resistance in shrimp fed with a lipopeptide diet. The test group also showed higher levels of digestive and immune enzymes, which suggests that the lipopeptide diet could positively modulate the digestive and immune activity of the shrimp. The gut microbiome profiling by Illumina high-throughput sequencing revealed that the most abundant genera in the lipopeptide diet-fed group were Adhaeribacter, Acidothermus, Brevibacillus, Candidatus, Mycobacterium, Rodopila, and Streptomyces, while opportunistic pathogens such as Streptococcus, Escherichia, Klebsiella, Neisseria, Rhizobium, and Salmonella were abundant in the control diet-fed shrimp. Also, lipopeptide diet-fed shrimp were found to have a high abundance of ammonia and nitrogen oxidizing bacteria, which are essential pollutant degraders. Therefore, the study reveals that the dietary supplementation of lipopeptide in shrimp aquaculture could positively modulate the gut microbiome and enhance the shrimp's overall health and immunity in an eco-friendly manner.
    Matched MeSH terms: Gastrointestinal Microbiome/physiology; Vibrio parahaemolyticus/physiology*
  12. Fulltext A gene co-expression network model identifies yield-related vicinity networks in Jatropha curcas shoot system
    Govender N, Senan S, Mohamed-Hussein ZA, Wickneswari R
    Sci Rep, 2018 Jun 15;8(1):9211.
    PMID: 29907786 DOI: 10.1038/s41598-018-27493-z
    The plant shoot system consists of reproductive organs such as inflorescences, buds and fruits, and the vegetative leaves and stems. In this study, the reproductive part of the Jatropha curcas shoot system, which includes the aerial shoots, shoots bearing the inflorescence and inflorescence were investigated in regard to gene-to-gene interactions underpinning yield-related biological processes. An RNA-seq based sequencing of shoot tissues performed on an Illumina HiSeq. 2500 platform generated 18 transcriptomes. Using the reference genome-based mapping approach, a total of 64 361 genes was identified in all samples and the data was annotated against the non-redundant database by the BLAST2GO Pro. Suite. After removing the outlier genes and samples, a total of 12 734 genes across 17 samples were subjected to gene co-expression network construction using petal, an R library. A gene co-expression network model built with scale-free and small-world properties extracted four vicinity networks (VNs) with putative involvement in yield-related biological processes as follow; heat stress tolerance, floral and shoot meristem differentiation, biosynthesis of chlorophyll molecules and laticifers, cell wall metabolism and epigenetic regulations. Our VNs revealed putative key players that could be adapted in breeding strategies for J. curcas shoot system improvements.
    Matched MeSH terms: Gene Expression Regulation, Plant/physiology*; Epigenesis, Genetic/physiology*; Gene Regulatory Networks/physiology*
  13. A generalized subspace approach for estimating visual evoked potentials
    Kamel N, Yusoff MZ
    Annu Int Conf IEEE Eng Med Biol Soc, 2008;2008:5208-11.
    PMID: 19163891 DOI: 10.1109/IEMBS.2008.4650388
    A "single-trial" signal subspace approach for extracting visual evoked potential (VEP) from the ongoing 'colored' electroencephalogram (EEG) noise is proposed. The algorithm applies the generalized eigendecomposition on the covariance matrices of the VEP and noise to transform them jointly into diagonal matrices in order to avoid a pre-whitening stage. The proposed generalized subspace approach (GSA) decomposes the corrupted VEP space into a signal subspace and noise subspace. Enhancement is achieved by removing the noise subspace and estimating the clean VEPs only from the signal subspace. The validity and effectiveness of the proposed GSA scheme in estimating the latencies of P100's (used in objective assessment of visual pathways) are evaluated using real data collected from Selayang Hospital in Kuala Lumpur. The performance of GSA is compared with the recently proposed single-trial technique called the Third Order Correlation (TOC).
    Matched MeSH terms: Evoked Potentials, Visual/physiology*; Visual Cortex/physiology*; Event-Related Potentials, P300/physiology*
  14. A hazard rate analysis of fertility using duration data from Malaysia
    Chang C
    Res Popul Econ, 1988;6:137-59.
    PMID: 12280927
    Matched MeSH terms: Physiology*
  15. Fulltext A highly thermostable crude endoglucanase produced by a newly isolated Thermobifida fusca strain UPMC 901
    Zainudin MHM, Mustapha NA, Hassan MA, Bahrin EK, Tokura M, Yasueda H, et al.
    Sci Rep, 2019 09 19;9(1):13526.
    PMID: 31537863 DOI: 10.1038/s41598-019-50126-y
    A thermophilic Thermobifida fusca strain UPMC 901, harboring highly thermostable cellulolytic activity, was successfully isolated from oil palm empty fruit bunch compost. Its endoglucanase had the highest activity at 24 hours of incubation in carboxymethyl-cellulose (CMC) and filter paper. A maximum endoglucanase activity of 0.9 U/mL was achieved at pH 5 and 60 °C using CMC as a carbon source. The endoglucanase properties were further characterized using crude enzyme preparations from the culture supernatant. Thermal stability indicated that the endoglucanase activity was highly stable at 70 °C for 24 hours. Furthermore, the activity was found to be completely maintained without any loss at 50 °C and 60 °C for 144 hours, making it the most stable than other endoglucanases reported in the literature. The high stability of the endoglucanase at an elevated temperature for a prolonged period of time makes it a suitable candidate for the biorefinery application.
    Matched MeSH terms: Enzyme Stability/physiology
  16. A hybrid of ant colony optimization and minimization of metabolic adjustment to improve the production of succinic acid in Escherichia coli
    Chong SK, Mohamad MS, Mohamed Salleh AH, Choon YW, Chong CK, Deris S
    Comput Biol Med, 2014 Jun;49:74-82.
    PMID: 24763079 DOI: 10.1016/j.compbiomed.2014.03.011
    This paper presents a study on gene knockout strategies to identify candidate genes to be knocked out for improving the production of succinic acid in Escherichia coli. Succinic acid is widely used as a precursor for many chemicals, for example production of antibiotics, therapeutic proteins and food. However, the chemical syntheses of succinic acid using the traditional methods usually result in the production that is far below their theoretical maximums. In silico gene knockout strategies are commonly implemented to delete the gene in E. coli to overcome this problem. In this paper, a hybrid of Ant Colony Optimization (ACO) and Minimization of Metabolic Adjustment (MoMA) is proposed to identify gene knockout strategies to improve the production of succinic acid in E. coli. As a result, the hybrid algorithm generated a list of knockout genes, succinic acid production rate and growth rate for E. coli after gene knockout. The results of the hybrid algorithm were compared with the previous methods, OptKnock and MOMAKnock. It was found that the hybrid algorithm performed better than OptKnock and MOMAKnock in terms of the production rate. The information from the results produced from the hybrid algorithm can be used in wet laboratory experiments to increase the production of succinic acid in E. coli.
    Matched MeSH terms: Escherichia coli/physiology
  17. Fulltext A large-scale forest fragmentation experiment: the Stability of Altered Forest Ecosystems Project
    Ewers RM, Didham RK, Fahrig L, Ferraz G, Hector A, Holt RD, et al.
    Philos Trans R Soc Lond B Biol Sci, 2011 Nov 27;366(1582):3292-302.
    PMID: 22006969 DOI: 10.1098/rstb.2011.0049
    Opportunities to conduct large-scale field experiments are rare, but provide a unique opportunity to reveal the complex processes that operate within natural ecosystems. Here, we review the design of existing, large-scale forest fragmentation experiments. Based on this review, we develop a design for the Stability of Altered Forest Ecosystems (SAFE) Project, a new forest fragmentation experiment to be located in the lowland tropical forests of Borneo (Sabah, Malaysia). The SAFE Project represents an advance on existing experiments in that it: (i) allows discrimination of the effects of landscape-level forest cover from patch-level processes; (ii) is designed to facilitate the unification of a wide range of data types on ecological patterns and processes that operate over a wide range of spatial scales; (iii) has greater replication than existing experiments; (iv) incorporates an experimental manipulation of riparian corridors; and (v) embeds the experimentally fragmented landscape within a wider gradient of land-use intensity than do existing projects. The SAFE Project represents an opportunity for ecologists across disciplines to participate in a large initiative designed to generate a broad understanding of the ecological impacts of tropical forest modification.
    Matched MeSH terms: Trees/physiology*; Arecaceae/physiology
  18. A level-set method for the evolution of cells and tissue during curvature-controlled growth
    Alias MA, Buenzli PR
    Int J Numer Method Biomed Eng, 2020 01;36(1):e3279.
    PMID: 31724309 DOI: 10.1002/cnm.3279
    Most biological tissues grow by the synthesis of new material close to the tissue's interface, where spatial interactions can exert strong geometric influences on the local rate of growth. These geometric influences may be mechanistic or cell behavioural in nature. The control of geometry on tissue growth has been evidenced in many in vivo and in vitro experiments, including bone remodelling, wound healing, and tissue engineering scaffolds. In this paper, we propose a generalisation of a mathematical model that captures the mechanistic influence of curvature on the joint evolution of cell density and tissue shape during tissue growth. This generalisation allows us to simulate abrupt topological changes such as tissue fragmentation and tissue fusion, as well as three dimensional cases, through a level-set-based method. The level-set method developed introduces another Eulerian field than the level-set function. This additional field represents the surface density of tissue-synthesising cells, anticipated at future locations of the interface. Numerical tests performed with this level-set-based method show that numerical conservation of cells is a good indicator of simulation accuracy, particularly when cusps develop in the tissue's interface. We apply this new model to several situations of curvature-controlled tissue evolutions that include fragmentation and fusion.
    Matched MeSH terms: Cancellous Bone/physiology
  19. A longitudinal study of age-related changes in intraocular pressure: the Kangbuk Samsung Health Study
    Zhao D, Kim MH, Pastor-Barriuso R, Chang Y, Ryu S, Zhang Y, et al.
    Invest Ophthalmol Vis Sci, 2014 Oct;55(10):6244-50.
    PMID: 25183763 DOI: 10.1167/iovs.14-14151
    To examine the longitudinal association between age and intraocular pressure (IOP) in a large sample of Korean men and women.
    Matched MeSH terms: Intraocular Pressure/physiology*
  20. A low-GI diet is associated with a short-term improvement of glycaemic control in Asian patients with type 2 diabetes
    Yusof BN, Talib RA, Kamaruddin NA, Karim NA, Chinna K, Gilbertson H
    Diabetes Obes Metab, 2009 Apr;11(4):387-96.
    PMID: 19175374 DOI: 10.1111/j.1463-1326.2008.00984.x
    AIMS: The aim of this study is to compare the efficacy of low glycaemic index (GI) vs. conventional carbohydrate exchange (CCE) dietary advice on glycaemic control and metabolic parameters in patients with type 2 diabetes.
    METHODS: A total of 104 patients with type 2 diabetes were randomly assigned to either a low GI (GI) or CCE dietary advice over a 12-week period. The primary end-point was glycaemic control as assessed by glycated haemoglobin A1c (HbA1c), fructosamine level and plasma glucose. The secondary end-points were anthropometric measurements and metabolic parameters that include blood pressure, lipid profile and insulin levels. The oral antidiabetic medications remained unchanged throughout the duration of the study.
    RESULTS: A low-GI diet was associated with significant changes in the fructosamine level (DeltaGI = -0.20 +/- 0.03; DeltaCCE = -0.08 +/- 0.03 mmol/l, p < 0.01) and waist circumference (DeltaGI group = -1.88 +/- 0.30 cm; DeltaCCE group: -0.36 +/- 0.4 cm, p < 0.05) at week 4. At week 12, the changes in fasting glucose (DeltaGI = -0.03 +/- 0.3; DeltaCCE = 0.7 +/- 0.3 mmol/l; p < 0.05) and waist circumference (DeltaGI = -2.35 +/- 0.47 cm; DeltaCCE group = -0.66 +/- 0.46 cm; p < 0.05) in the GI group was significantly lower than the CCE group. With the low-GI diet, the changes in postprandial glycaemia at time 0, 60, 150 and 180 min after consuming the standard test meal was lower than with the CCE diet (p < 0.05). No significant differences were found between the groups for the remaining parameters that were measured.
    CONCLUSIONS: Use of a low-GI diet resulted in significant changes of serum fructosamine level, plasma glucose and waist circumference in Asian patients with type 2 diabetes over a 12-week period compared with those following a CCE diet. The effect on HbA1c and other metabolic parameters was not significantly different between the two study groups but the improvement within the GI group was more pronounced and of clinical benefit.
    Matched MeSH terms: Energy Intake/physiology; Postprandial Period/physiology
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