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  1. Bin Naharudin MN, Yusof A, Shaw H, Stockton M, Clayton DJ, James LJ
    J Strength Cond Res, 2019 Jul;33(7):1766-1772.
    PMID: 30707135 DOI: 10.1519/JSC.0000000000003054
    Bin Naharudin, MN, Yusof, A, Shaw, H, Stockton, M, Clayton, DJ, and James, LJ. Breakfast omission reduces subsequent resistance exercise performance. J Strength Cond Res 33(7): 1766-1772, 2019-Although much research has examined the influence of morning carbohydrate intake (i.e., breakfast) on endurance performance, little is known about its effects on performance in resistance-type exercise. Sixteen resistance-trained men (age 23 ± 4 years, body mass 77.56 ± 7.13 kg, and height 1.75 ± 0.04 m) who regularly (≥3 day/wk) consumed breakfast completed this study. After assessment of 10 repetition maximum (10RM) and familiarization process, subjects completed 2 randomized trials. After an overnight fast, subjects consumed either a typical breakfast meal (containing 1.5 g of carbohydrate/kg; breakfast consumption [BC]) or a water-only breakfast (breakfast omission [BO]). Two hours later, subjects performed 4 sets to failure of back squat and bench press at 90% of their 10RM. Sensations of hunger, fullness, desire to eat, and prospective food consumption were collected before, as well as immediately, 1 hour and 2 hours after BC/BO using 100-mm visual analogue scales. Total repetitions completed were lower during BO for both back squat (BO: 58 ± 11 repetitions; BC: 68 ± 14 repetitions; effect size [ES] = 0.98; p < 0.001) and bench press (BO: 38 ± 5 repetitions; BC: 40 ± 5 repetitions; ES = 1.06; p < 0.001). Fullness was greater, whereas hunger, desire to eat, and prospective food consumption were lower after a meal for BC compared with BO (p < 0.001). The results of this study demonstrate that omission of a pre-exercise breakfast might impair resistance exercise performance in habitual breakfast consumers. Therefore, consumption of a high-carbohydrate meal before resistance exercise might be a prudent strategy to help maximize performance.
    Matched MeSH terms: Energy Intake/physiology; Hunger/physiology; Athletic Performance/physiology*
  2. Widihastuty, Tobing MC, Marheni, Kuswardani RA, Fudholi A
    J Insect Physiol, 2020 07 17;125:104089.
    PMID: 32687849 DOI: 10.1016/j.jinsphys.2020.104089
    Ants are social insects with some significant roles in the ecosystem, including acting as predators for various insect pests. Myopopone castanea ants is a predatorfor the larvae of Oryctes rhinoceros pest. The existence of a similar niche of life between M. castanea ants and O. rhinoceros larvae opens an excellent opportunity to utilize these ants as biological agents. The research was conducted to study some aspects biology of M. castanea so that later it can be applied to mass rearing of natural enemies in the laboratory. The study was conducted by maintaining 50 eggs of M. castanea ant. Then, the eggs placed on two pieces of decayed palm oil stem together with twenty individual worker ants and ten individual end instar larvae. It needs five replications for the experiment. The results showed that egg stadia length was 13.8 days. It found five instars within M. castanea ant larvae with varying lengths of each stage. It takes 17.2 days for worker ant pupae to go through stadia pupa and 17.9 days for female ant pupae. The survival rate of M. castanea ant life from eggs until imago is 56.4%, which means that from several groups of eggs laid by queen ants, only about half have succeeded in becoming ant imago.
    Matched MeSH terms: Ants/physiology*; Larva/physiology; Pupa/physiology
  3. Hairol MI, Nordin N, P'ng J, Sharanjeet-Kaur S, Narayanasamy S, Mohd-Ali M, et al.
    PLoS One, 2021;16(3):e0246846.
    PMID: 33657109 DOI: 10.1371/journal.pone.0246846
    Visual-motor integration (VMI) is related to children's academic performance and school readiness. VMI scores measured using the Beery-Bucktenicka Developmental Test of Visual-Motor Integration (Beery-VMI) can differ due to differences in cultural and socioeconomic backgrounds. This study compared the VMI scores of Malaysian preschoolers with the corresponding US norms and determined the association between their VMI scores and socioeconomic factors. A cross-sectional study was conducted among 435 preschoolers (mean age: 5.95±0.47 years; age range: 5.08-6.83 years) from randomly selected public and private preschools. VMI scores were measured using Beery-VMI in the preschools' classrooms. Information on the socioeconomic characteristics of the preschoolers was obtained using a parent-report questionnaire. One sample t-test was used to compare their VMI scores with the corresponding US norms. Multivariate logistic regression models were used to explore the influence of socioeconomic factors on the preschoolers' VMI scores. Overall, Malaysian preschoolers' VMI performance was similar to the US standardized norms (p>0.05). Children from low-income families were twice likely to obtain lower than average VMI scores than those from higher-income families (OR = 2.47, 95%CI 1.05, 5.86). Children enrolled at public preschools were more likely to obtain a lower than average VMI score than those who enrolled at private preschools (OR = 2.60, 95%CI 1.12, 6.06). Children who started preschool at the age of six were more likely to obtain lower than average VMI scores than those who started at an earlier age (OR = 4.66, 95%CI 1.97, 11.04). Low maternal education level was also associated with lower than average VMI score (OR = 2.60, 95%CI 1.12, 6.06). Malaysian preschoolers' Beery-VMI performance compared well to their US counterparts. Some socioeconomic factors were associated with reduced VMI scores. Those from disadvantaged socioeconomic backgrounds are more likely to have reduced VMI performance, potentially adversely affecting their school readiness, cognitive performance, and future academic achievements.
    Matched MeSH terms: Child Development/physiology; Psychomotor Performance/physiology*; Visual Perception/physiology*
  4. Lim AC, Chong VC, Chew WX, Muniandy SV, Wong CS, Ong ZC
    J Acoust Soc Am, 2015 Jul;138(1):404-12.
    PMID: 26233039 DOI: 10.1121/1.4923153
    Acoustic signals of the tiger-tail seahorse (Hippocampus comes) during feeding were studied using wavelet transform analysis. The seahorse "click" appears to be a compounded sound, comprising three acoustic components that likely come from two sound producing mechanisms. The click sound begins with a low-frequency precursor signal, followed by a sudden high-frequency spike that decays quickly, and a final, low-frequency sinusoidal component. The first two components can, respectively, be traced to the sliding movement and forceful knock between the supraorbital bone and coronet bone of the cranium, while the third one (purr) although appearing to be initiated here is produced elsewhere. The seahorse also produces a growling sound when under duress. Growling is accompanied by the highest recorded vibration at the cheek indicating another sound producing mechanism here. The purr has the same low frequency as the growl; both are likely produced by the same structural mechanism. However, growl and purr are triggered and produced under different conditions, suggesting that such "vocalization" may have significance in communication between seahorses.
    Matched MeSH terms: Skull/physiology; Vocalization, Animal/physiology*; Smegmamorpha/physiology*
  5. Chow BC, Li S, Zhu X, Jiao J, Quach B, Baker JS, et al.
    J Sports Sci, 2021 Mar;39(5):496-502.
    PMID: 33012244 DOI: 10.1080/02640414.2020.1829362
    We examined the effects of descending (DSE) or ascending (ASE) stair exercise on body composition, insulin sensitivity, and inflammatory markers in young Chinese women with obesity. Thirty-six participants were randomly assigned into three groups DSE, ASE and a control group. The DSE and ASE groups performed three sessions of stair walking per week for 12 weeks with a gradual increase in repetitions. Following the exercise interventions, body composition related variables obtained by Dual-energy X-ray absorptiometry scans significantly decreased. Abdominal fat decreased in the DSE group only. Moreover, Insulin sensitivity improved significantly 3.5-fold in the DSE group compared with ASE group (insulin: -33.2% vs. -9.8%, homoeostasis model assessment for insulin resistance: -35.6% vs. -10.8%). Pro-inflammatory factors showed significant decreases in tumour necrosis factor-α (TNF-α) (-39.9% vs. -23.2%) for both intervention groups. The reduction in TNF-α concentrations in the DSE group was significantly different compared to the other two groups. Interleukin-6 significantly decreased in both exercise protocols. Our results show that 12-weeks induced stair walking improved body composition parameters in Chinese females with obesity. The results also demonstrate the superiority of the DSE protocol for improving insulin sensitivity. These findings may be attributable to the decreases observed in TNF- α levels.
    Matched MeSH terms: Body Composition/physiology*; Insulin Resistance/physiology*; Stair Climbing/physiology*
  6. Kugan HM, Rejab NA, Sahruzaini NA, Harikrishna JA, Baisakh N, Cheng A
    Int J Mol Sci, 2021 Apr 27;22(9).
    PMID: 33925559 DOI: 10.3390/ijms22094588
    The natural timing devices of organisms, commonly known as biological clocks, are composed of specific complex folding molecules that interact to regulate the circadian rhythms. Circadian rhythms, the changes or processes that follow a 24-h light-dark cycle, while endogenously programmed, are also influenced by environmental factors, especially in sessile organisms such as plants, which can impact ecosystems and crop productivity. Current knowledge of plant clocks emanates primarily from research on Arabidopsis, which identified the main components of the circadian gene regulation network. Nonetheless, there remain critical knowledge gaps related to the molecular components of circadian rhythms in important crop groups, including the nitrogen-fixing legumes. Additionally, little is known about the synergies and trade-offs between environmental factors and circadian rhythm regulation, especially how these interactions fine-tune the physiological adaptations of the current and future crops in a rapidly changing world. This review highlights what is known so far about the circadian rhythms in legumes, which include major as well as potential future pulse crops that are packed with nutrients, particularly protein. Based on existing literature, this review also identifies the knowledge gaps that should be addressed to build a sustainable food future with the reputed "poor man's meat".
    Matched MeSH terms: Circadian Rhythm/physiology*; Fabaceae/physiology*; Circadian Clocks/physiology
  7. Hamzah N, Kasmuri N, Tao W, Singhal N, Padhye L, Swift S
    Braz J Microbiol, 2020 Sep;51(3):1317-1326.
    PMID: 32399689 DOI: 10.1007/s42770-020-00295-0
    Bacterial adhesion on surfaces is an essential initial step in promoting bacterial mobilization for soil bioremediation process. Modification of the cell surface is required to improve the adhesion of bacteria. The modification of physicochemical properties by rhamnolipid to Pseudomonas putida KT2442, Rhodococcus erythropolis 3586 and Aspergillus brasiliensis ATCC 16404 strains was analysed using contact angle measurements. The surface energy and total free energy of adhesion were calculated to predict the adhesion of both bacteria strains on the A. brasiliensis surface. The study of bacterial adhesion was carried out to evaluate experimental value with the theoretical results. Bacteria and fungi physicochemical properties were modified significantly when treated with rhamnolipid. The adhesion rate of P. putida improved by 16% with the addition of rhamnolipid (below 1 CMC), while the increase of rhamnolipid concentration beyond 1 CMC did not further enhance the bacterial adhesion. The addition of rhamnolipid did not affect the adhesion of R. erythropolis. A good relationship has been obtained in which water contact angle and surface energy of fungal surfaces are the major factors contributing to the bacterial adhesion. The adhesion is mainly driven by acid-base interaction. This finding provides insight to the role of physicochemical properties in controlling the bacterial adhesion on the fungal surface to enhance bacteria transport in soil bioremediation.
    Matched MeSH terms: Aspergillus/physiology; Pseudomonas aeruginosa/physiology; Rhodococcus/physiology
  8. Majumder C, Afnan H
    Korean J Ophthalmol, 2020 06;34(3):219-226.
    PMID: 32495530 DOI: 10.3341/kjo.2019.0138
    PURPOSE: The purpose of the study was to establish baseline data for amplitude of accommodation (AA) measured using both subjective and objective techniques in students at a private Malaysian university.

    METHODS: This cross-sectional study was conducted including 34 healthy participants with a mean age of 22.26 ± 1.88 years. AA was measured using dynamic retinoscopy and the push-up, pull-away, modified push-up, and minus-lens techniques.

    RESULTS: The mean AA scores for the push-up, pull-away, minus-lens, and modified push-up techniques and dynamic retinoscopy were 11.38 ± 2.03, 10.35 ± 1.64, 9.24 ± 1.18, 8.26 ± 1.44, and 7.2 ± 1.0 diopters, respectively. No AA measurements showed significant difference among ethnicities (Chinese, Malay, and Indian). This study suggested that AA obtained using push-up (p = 0.005) and pull-away (p = 0.017) methods and dynamic retinoscopy (p = 0.041) were significantly different according to sex. No significant difference was observed in AA for the minus-lens (p = 0.051) and modified push-up (p = 0.216) techniques by sex. A moderately negative correlation was found between AA and age for the push-up (r = -0.434, p = 0.010), pull-away (r = -0.412, p = 0.016), and minus-lens (r = -0.509, p = 0.002) techniques and dynamic retinoscopy (r = -0.497, p = 0.003). A weak negative correlation was found between age and AA measured using a modified push-up technique (r = -0.393, p = 0.022).

    CONCLUSIONS: Mean AA was highest for the push-up technique, followed by the pull-away technique, the minus-lens technique, the modified push up technique, and dynamic retinoscopy. The push-up and pull-away methods and dynamic retinoscopy showed a significant difference in measurement of AA between sexes.

    Matched MeSH terms: Accommodation, Ocular/physiology*; Lens, Crystalline/physiology*; Refraction, Ocular/physiology*
  9. Vythilingam I
    Trop Biomed, 2010 Apr;27(1):1-12.
    PMID: 20562807 MyJurnal
    Plasmodium knowlesi in humans is life threatening, is on the increase and has been reported from most states in Malaysia. Anopheles latens and Anopheles cracens have been incriminated as vectors. Malaria is now a zoonoses and is occurring in malaria free areas of Malaysia. It is also a threat to eco-tourism. The importance of the vectors and possible control measures is reviewed here.
    Matched MeSH terms: Anopheles/physiology; Insect Vectors/physiology; Plasmodium knowlesi/physiology*
  10. Oli K, Jeffery J, Vythilingam I
    Trop Biomed, 2005 Dec;22(2):249-51.
    PMID: 16883295 MyJurnal
    Adult mosquito collections were conducted for 12 weeks in two residential areas in Kuala Lumpur. The CDC light traps were compared using dry ice and yeast as sources of carbon dioxide attractants for mosquitoes. The efficacy of the dry ice baited trap was significant over yeast generated CO2 trap. The predominant species obtained were Culex quinquefasciatus, Stegomyia albopicta and Armigeres subalbatus.
    Matched MeSH terms: Aedes/physiology; Culex/physiology; Culicidae/physiology*
  11. Yong VW, Tan YJ, Ng YD, Choo XY, Sugumaran K, Chinna K, et al.
    Parkinsonism Relat Disord, 2020 08;77:28-35.
    PMID: 32615497 DOI: 10.1016/j.parkreldis.2020.06.015
    INTRODUCTION: Although weight loss is common in Parkinson's disease (PD), longitudinal studies assessing weight and body composition changes are limited.

    METHODS: In this three-year longitudinal study, 125 subjects (77 PD patients and 48 spousal/sibling controls) underwent clinical, biochemical and body composition assessments using dual-energy X-ray absorptiometry.

    RESULTS: Patients were older than controls (65.6 ± 8.9 vs. 62.6 ± 7.1, P = 0.049), with no significant differences in gender, comorbidities, dietary intake and physical activity. Clinically significant weight loss (≥5% from baseline weight) was recorded in 41.6% of patients, with a doubling of cases (6.5 to 13.0%) classified as underweight at study end. Over three years, patients demonstrated greater reductions in BMI (mean -1.2 kg/m2, 95%CI-2.0 to -0.4), whole-body fat percentage (-2.5% points, 95%CI-3.9 to -1.0), fat mass index (FMI) (-0.9 kg/m2, 95%CI-1.4 to -0.4), visceral fat mass (-0.1 kg, 95%CI-0.2 to 0.0), and subcutaneous fat mass (-1.9 kg, 95%CI-3.4 to -0.5) than in controls, with significant group-by-time interactions after adjusting for age and gender. Notably, 31.2% and 53.3% of patients had FMI<3rd (severe fat deficit) and <10th centiles, respectively. Muscle mass indices decreased over time in both groups, without significant group-by-time interactions. Multiple linear regression models showed that loss of body weight and fat mass in patients were associated with age, dyskinesia, psychosis and constipation.

    CONCLUSIONS: We found progressive loss of weight in PD patients, with greater loss of both visceral and subcutaneous fat, but not muscle, compared to controls. Several associated factors (motor and non-motor disease features) were identified for these changes, providing insights on possible mechanisms and therapeutic targets.

    Matched MeSH terms: Body Composition/physiology*; Body Weight/physiology*; Weight Loss/physiology*
  12. da Silva LG, Kawanishi K, Henschel P, Kittle A, Sanei A, Reebin A, et al.
    PLoS One, 2017;12(4):e0170378.
    PMID: 28379961 DOI: 10.1371/journal.pone.0170378
    The geographic distribution and habitat association of most mammalian polymorphic phenotypes are still poorly known, hampering assessments of their adaptive significance. Even in the case of the black panther, an iconic melanistic variant of the leopard (Panthera pardus), no map exists describing its distribution. We constructed a large database of verified records sampled across the species' range, and used it to map the geographic occurrence of melanism. We then estimated the potential distribution of melanistic and non-melanistic leopards using niche-modeling algorithms. The overall frequency of melanism was ca. 11%, with a significantly non-random spatial distribution. Distinct habitat types presented significantly different frequencies of melanism, which increased in Asian moist forests and approached zero across most open/dry biomes. Niche modeling indicated that the potential distributions of the two phenotypes were distinct, with significant differences in habitat suitability and rejection of niche equivalency between them. We conclude that melanism in leopards is strongly affected by natural selection, likely driven by efficacy of camouflage and/or thermoregulation in different habitats, along with an effect of moisture that goes beyond its influence on vegetation type. Our results support classical hypotheses of adaptive coloration in animals (e.g. Gloger's rule), and open up new avenues for in-depth evolutionary analyses of melanism in mammals.
    Matched MeSH terms: Selection, Genetic/physiology; Panthera/physiology*; Animal Distribution/physiology
  13. Ichie T, Inoue Y, Takahashi N, Kamiya K, Kenzo T
    J Plant Res, 2016 Jul;129(4):625-635.
    PMID: 26879931 DOI: 10.1007/s10265-016-0795-2
    The vertical structure of a tropical rain forest is complex and multilayered, with strong variation of micro-environment with height up to the canopy. We investigated the relation between morphological traits of leaf surfaces and tree ecological characteristics in a Malaysian tropical rain forest. The shapes and densities of stomata and trichomes on the abaxial leaf surfaces and their relation with leaf characteristics such as leaf area and leaf mass per area (LMA) were studied in 136 tree species in 35 families with different growth forms in the tropical moist forest. Leaf physiological properties were also measured in 50 canopy and emergent species. Most tree species had flat type (40.4 %) or mound type (39.7 %) stomata. In addition, 84 species (61.76 %) in 22 families had trichomes, including those with glandular (17.65 %) and non-glandular trichomes (44.11 %). Most leaf characteristics significantly varied among the growth form types: species in canopy and emergent layers and canopy gap conditions had higher stomatal density, stomatal pore index (SPI), trichome density and LMA than species in understory and subcanopy layers, though the relation of phylogenetically independent contrasts to each characteristic was not statistically significant, except for leaf stomatal density, SPI and LMA. Intrinsic water use efficiency in canopy and emergent tree species with higher trichome densities was greater than in species with lower trichome densities. These results suggest that tree species in tropical rain forests adapt to a spatial difference in their growth forms, which are considerably affected by phylogenetic context, by having different stomatal and trichome shapes and/or densities.
    Matched MeSH terms: Trees/physiology*; Plant Stomata/physiology*; Trichomes/physiology*
  14. Shariat A, Lam ETC, Shaw BS, Shaw I, Kargarfard M, Sangelaji B
    J Back Musculoskelet Rehabil, 2017;30(3):641-647.
    PMID: 28372315 DOI: 10.3233/BMR-160526
    STUDY DESIGN: True experimental design.

    BACKGROUND: The back squat is an integral aspect of any resistance training program to improve athletic performance. It is also used for injury prevention of the lower limbs.

    OBJECTIVE: The purpose of this study was to examine the effect of back squat training at different intensities on strength and flexibility of the hamstring muscle group (HMG).

    METHODS: Twenty-two male recreational bodybuilders with at least two years of experience in resistance training were recruited to participate in a nine-week training program. They were randomly assigned to a heavy back squat group (90-95% of one repetition maximum) or a moderate-intensity back squat group (60-65% of one repetition maximum).

    RESULTS: The heavy back squat group resulted in a significantly (p < 0.001) increased in one repetition maximum strength but a significant (p < 0.001) reduction in HMG flexibility when compared to their counterparts. The results of the study indicate that while a heavy back squat training program is effective in improving strength, it has an adverse effect on the flexibility of the HMG.

    CONCLUSION: The implication of this study is that there is a tradeoff between strength and flexibility and trainers should select the appropriate training protocols for their athletes to maximize athletic performance.

    Matched MeSH terms: Muscle, Skeletal/physiology; Muscle Strength/physiology; Hamstring Muscles/physiology*
  15. 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
  16. Jalaei B, Azmi MHAM, Zakaria MN
    Braz J Otorhinolaryngol, 2018 05 17;85(4):486-493.
    PMID: 29858160 DOI: 10.1016/j.bjorl.2018.04.005
    INTRODUCTION: Binaurally evoked auditory evoked potentials have good diagnostic values when testing subjects with central auditory deficits. The literature on speech-evoked auditory brainstem response evoked by binaural stimulation is in fact limited. Gender disparities in speech-evoked auditory brainstem response results have been consistently noted but the magnitude of gender difference has not been reported.

    OBJECTIVE: The present study aimed to compare the magnitude of gender difference in speech-evoked auditory brainstem response results between monaural and binaural stimulations.

    METHODS: A total of 34 healthy Asian adults aged 19-30 years participated in this comparative study. Eighteen of them were females (mean age=23.6±2.3 years) and the remaining sixteen were males (mean age=22.0±2.3 years). For each subject, speech-evoked auditory brainstem response was recorded with the synthesized syllable /da/ presented monaurally and binaurally.

    RESULTS: While latencies were not affected (p>0.05), the binaural stimulation produced statistically higher speech-evoked auditory brainstem response amplitudes than the monaural stimulation (p<0.05). As revealed by large effect sizes (d>0.80), substantive gender differences were noted in most of speech-evoked auditory brainstem response peaks for both stimulation modes.

    CONCLUSION: The magnitude of gender difference between the two stimulation modes revealed some distinct patterns. Based on these clinically significant results, gender-specific normative data are highly recommended when using speech-evoked auditory brainstem response for clinical and future applications. The preliminary normative data provided in the present study can serve as the reference for future studies on this test among Asian adults.

    Matched MeSH terms: Speech/physiology*; Speech Perception/physiology*; Evoked Potentials, Auditory, Brain Stem/physiology*
  17. Masni-Azian, Tanaka M
    Comput Biol Med, 2018 07 01;98:26-38.
    PMID: 29758454 DOI: 10.1016/j.compbiomed.2018.05.010
    Intervertebral disc degeneration involves changes in its material properties that affect the mechanical functions of the spinal system. However, the alteration of the biomechanics of a spinal segment through specific material degradation in a specific region is poorly understood. In this study, the influence of the constitutive material degeneration of disc tissues on the mechanics of a lower lumbar spinal unit was examined using a three-dimensional nonlinear finite element model of the L4-L5 functional spinal unit. Different grades of disc degeneration were simulated by introducing a degeneration factor to the corresponding material properties to represent fibrous nucleus, increased fibre and ground substance laxity, increased fibre stiffness and total annular fracture along posterior and posterolateral regions. The model was loaded with an axial compression of 500 N and pure moments of up to 10 Nm to simulate extension, flexion, lateral bending and axial rotation. To validate the model, the spinal motion and intradiscal pressure of healthy and degenerated discs with existing in vitro data were compared. The disc with a fibrous nucleus and the presence of intradiscal pressure increase the spinal instability during flexion and axial rotation, and the absence of intradiscal pressure increases the spinal instability in all directions. Bulging displacement and shear strains in the disc with total fracture and ground substance laxity are high in all of the loading cases. Our study could provide useful information to enhance our understanding of the influence of each constitutive component of the intervertebral disc on the mechanics of the spinal segment.
    Matched MeSH terms: Biomechanical Phenomena/physiology*; Intervertebral Disc/physiology*; Range of Motion, Articular/physiology
  18. El Haj M, Janssen SMJ, Antoine P
    Brain Cogn, 2017 10;117:65-72.
    PMID: 28629646 DOI: 10.1016/j.bandc.2017.06.005
    Backward and forward telescoping are opposite timing biases. The former refers to misattributing events to earlier dates, whereas the latter refers to misattributing events to later dates. The present study investigated both biases in participants with Alzheimer's Disease (AD) and healthy older adults, matched on age, sex, and education level. Participants were asked to recall the years when five remote and five recent public events had occurred. They were also assessed with a cognitive and clinical battery that included a context memory task on which they had to associate letters and locations. Results showed backward telescoping for recent events and forward telescoping for remote events in AD participants and older adults. Furthermore, poorer context recall was observed in AD participants and older adults displaying backward telescoping than in those displaying forward telescoping. These findings suggest an association between the amount of contextual information recalled and the direction of the timing bias. Backward telescoping can be associated with deficiencies in retrieving context characteristics of events, which have been associated with retrograde amnesia and pathological changes to the hippocampus in AD.
    Matched MeSH terms: Memory/physiology*; Mental Recall/physiology; Time Perception/physiology*
  19. Law JX, Chowdhury SR, Aminuddin BS, Ruszymah BHI
    Cell Tissue Bank, 2017 Dec;18(4):585-595.
    PMID: 28748415 DOI: 10.1007/s10561-017-9645-2
    Fibrin has excellent biocompatibility and biological properties to support tissue regeneration and promote wound healing. However, the role of diluted fibrin in wound healing has yet to be elucidated as it is commonly used in high concentration. This study was aimed to examine the effects of diluted plasma-derived fibrin (PDF) on keratinocyte and fibroblast wound healing in term of cell proliferation, migration, extracellular matrix (ECM) production and soluble factor secretion. Two PDF concentrations, 10 and 20% (v/v) were tested on keratinocytes and fibroblasts indirectly co-cultured in the transwell system. The control group was cultured with 5% FBS. Results showed that PDF reduced the keratinocyte growth rate and fibroblast migration, and increased the fibroblast ECM gene expression whereby significant differences were found between the 20% PDF group and the 5% FBS group. Similar trend was seen for the 10% PDF group but the differences were not significant. Comparison of the soluble factors between the PDF groups demonstrated that the level of growth-related oncogene alpha, interleukin-8 and epithelial neutrophil-activating peptide-78 were significantly higher in the 10% PDF group, whilst interleukin-1 alpha and granulocyte-macrophage colony stimulating factor were significantly more concentrated in the 20% PDF group. Our results suggested that PDF selectively elevated the expression of collagen type 1 and collagen type 3 in fibroblasts but slowed down the migration in concentration-dependent manner. These novel findings provide new insight into the role of PDF in wound healing and may have important implications for the use of fibrin in skin tissue engineering.
    Matched MeSH terms: Cell Movement/physiology; Wound Healing/physiology*; Cell Proliferation/physiology
  20. Rosli Y, Maddess T, Dawel A, James AC
    Clin Neurophysiol, 2009 Dec;120(12):2100-2108.
    PMID: 19846337 DOI: 10.1016/j.clinph.2009.09.006
    OBJECTIVE: To examine the feasibility of a multifocal visual evoked potential (mfVEP) binocularly, using a variant of the multifocal frequency-doubling (FD) pattern-electroretinogram (MFP).

    METHODS: Stimuli were presented in both monocular and dichoptic conditions at eight visual field locations/eye. The incommensurate stimulus frequencies ranged from 15.45 to 21.51 Hz. Five stimulus conditions differing in spatial frequency and orientation were examined for three viewing conditions. The resulting 15 stimulus conditions were examined in 16 normal subjects who repeated all conditions twice.

    RESULTS: Several significant independent effects were identified. Response amplitudes were reduced for dichoptic viewing (by 0.85 times, p<4 x 10(-11)); offset by increases in responses for between eye differences of one octave of spatial frequency: lower (1.15 times, 0.1 cpd); higher (1.29 times, 0.4 cpd), both p<1.8 x 10(-7). Crossed orientations produced significant effects upon response phase (p=0.023) but not amplitude (p=0.062).

    CONCLUSIONS: The results indicated that dichoptic evoked potentials using multifocal frequency-doubling illusion stimuli are practical. The use of crossed orientation, or differing spatial frequencies, in the two eyes reduced binocular interactions.

    SIGNIFICANCE: The results indicate a method wherein several spatial or temporal and frequencies per visual field region can be tested in reasonable time using a multifocal VEP using spatial frequency-doubling stimuli.

    Matched MeSH terms: Evoked Potentials, Visual/physiology*; Pattern Recognition, Visual/physiology*; Vision, Binocular/physiology
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