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  1. EMG-force relationship during static contraction: effects on sensor placement locations on biceps brachii muscle
    Ahamed NU, Sundaraj K, Alqahtani M, Altwijri O, Ali MA, Islam MA
    Technol Health Care, 2014;22(4):505-13.
    PMID: 25059255 DOI: 10.3233/THC-140842
    BACKGROUND: The relationship between surface electromyography (EMG) and force have been the subject of ongoing investigations and remain a subject of controversy. Even under static conditions, the relationships at different sensor placement locations in the biceps brachii (BB) muscle are complex.

    OBJECTIVE: The aim of this study was to compare the activity and relationship between surface EMG and static force from the BB muscle in terms of three sensor placement locations.

    METHODS: Twenty-one right hand dominant male subjects (age 25.3±1.2 years) participated in the study. Surface EMG signals were detected from the subject's right BB muscle. The muscle activation during force was determined as the root mean square (RMS) electromyographic signal normalized to the peak RMS EMG signal of isometric contraction for 10 s. The statistical analysis included linear regression to examine the relationship between EMG amplitude and force of contraction [40-100% of maximal voluntary contraction (MVC)], repeated measures ANOVA to assess differences among the sensor placement locations, and coefficient of variation (CoV) for muscle activity variation.

    RESULTS: The results demonstrated that when the sensor was placed on the muscle belly, the linear slope coefficient was significantly greater for EMG versus force testing (r2=0.62, P<0.05) than when placed on the lower part (r2=0.31, P>0.05) and upper part of the muscle belly (r2=0.29, P<0.05). In addition, the EMG signal activity on the muscle belly had less variability than the upper and lower parts (8.55% vs. 15.12% and 12.86%, respectively).

    CONCLUSION: These findings indicate the importance of applying the surface EMG sensor at the appropriate locations that follow muscle fiber orientation of the BB muscle during static contraction. As a result, EMG signals of three different placements may help to understand the difference in the amplitude of the signals due to placement.

    Matched MeSH terms: Muscle Contraction/physiology*; Muscle, Skeletal/physiology*
  2. Enhancing motor imagery EEG signal decoding through machine learning: A systematic review of recent progress
    Hameed I, Khan DM, Ahmed SM, Aftab SS, Fazal H
    Comput Biol Med, 2025 Feb;185:109534.
    PMID: 39672015 DOI: 10.1016/j.compbiomed.2024.109534
    This systematic literature review explores the intersection of neuroscience and deep learning in the context of decoding motor imagery Electroencephalogram (EEG) signals to enhance the quality of life for individuals with motor disabilities. Currently, the most used non-invasive method for measuring brain activity is the EEG, due to its high temporal resolution, user-friendliness, and safety. A Brain Computer Interface (BCI) framework can be made using these signals which can provide a new communication channel to people that are suffering from motor disabilities or other neurological disorders. However, implementing EEG-based BCI systems in real-world scenarios for motor imagery recognition presents challenges, primarily due to the inherent variability among individuals and low signal-to-noise ratio (SNR) of EEG signals. To assist researchers in navigating this complex problem, a comprehensive review article is presented, summarizing the key findings from relevant studies since 2017. This review primarily focuses on the datasets, preprocessing methods, feature extraction techniques, and deep learning models employed by various researchers. This review aims to contribute valuable insights and serve as a resource for researchers, practitioners, and enthusiasts interested in the combination of neuroscience and deep learning, ultimately hoping to contribute to advancements that bridge the gap between the human mind and machine interfaces.
    Matched MeSH terms: Brain/physiology; Imagination/physiology
  3. Fulltext Measuring Speech Discrimination Ability in Sleeping Infants Using fNIRS-A Proof of Principle
    Lee OW, Gao D, Peng T, Wunderlich J, Mao D, Balasubramanian G, et al.
    Trends Hear, 2025;29:23312165241311721.
    PMID: 39850978 DOI: 10.1177/23312165241311721
    This study used functional near-infrared spectroscopy (fNIRS) to measure aspects of the speech discrimination ability of sleeping infants. We examined the morphology of the fNIRS response to three different speech contrasts, namely "Tea/Ba," "Bee/Ba," and "Ga/Ba." Sixteen infants aged between 3 and 13 months old were included in this study and their fNIRS data were recorded during natural sleep. The stimuli were presented using a nonsilence baseline paradigm, where repeated standard stimuli were presented between the novel stimuli blocks without any silence periods. The morphology of fNIRS responses varied between speech contrasts. The data were fit with a model in which the responses were the sum of two independent and concurrent response mechanisms that were derived from previously published fNIRS detection responses. These independent components were an oxyhemoglobin (HbO)-positive early-latency response and an HbO-negative late latency response, hypothesized to be related to an auditory canonical response and a brain arousal response, respectively. The goodness of fit of the model with the data was high with median goodness of fit of 81%. The data showed that both response components had later latency when the left ear was the test ear (p 
    Matched MeSH terms: Brain/physiology; Discrimination (Psychology)/physiology
  4. Fulltext Prenatal auditory stimulation and impacts on physiological response to feed restriction in broiler chickens at market age
    Ahmad-Hanafi S, Zulkifli I, Ramiah SK, Chung ELT, Kamil R, Sazili AQ, et al.
    Poult Sci, 2024 Oct;103(10):103948.
    PMID: 39127008 DOI: 10.1016/j.psj.2024.103948
    Feed restriction could induce physiological stress in broiler chickens, leading to welfare issues. Prenatal stimulation could improve stress-coping mechanisms in poultry. The present study aimed to elucidate the effects of subjecting developing embryos to auditory stimulation on physiological stress response to feed restriction in broiler chickens at market age. A total of 423 hatching eggs of Cobb 500 (Gallus domesticus) were subjected to the following auditory treatments: 1) no additional sound treatment other than the background sound of the incubator's compressors at 40 dB (CONTROL), 2) exposure to pre-recorded traffic noise at 90 dB (NOISE), and 3) exposure to Mozart's Sonata for Two Pianos in D Major, K 488 at 90 dB) (MUSIC). The NOISE and MUSIC treatments were for 20 min/h for 24 h (a total of 8 h/d), starting from embryonic days (ED) 12 to hatching. On d 42, an equal number of birds from each prenatal auditory stimulation (PAS) group were subjected to either ad libitum feeding (AL) or 30-h of feed restriction (FR) in a completely randomised design. The FR chickens exhibited significantly higher serum levels of corticosterone (CORT), and heat shock protein (HSP) 70 compared to those of AL. Prenatal auditory stimulation, particularly NOISE, led to lower serum levels of CORT and alpha-1-acid glycoprotein (AGP) levels compared to the CONTROL group. Additionally, NOISE significantly increased brain mRNA glucocorticoid receptor and HSP70 gene expression. The cecal population of E. coli and Lactobacillus spp. was not significantly affected by prenatal auditory stimulation. In conclusion, our findings suggest that prenatal auditory stimulation, particularly NOISE, positively impacts broiler chickens' ability to cope with feed restriction.
    Matched MeSH terms: Chick Embryo/physiology; Food Deprivation/physiology
  5. Longitudinally Predicting Behavioral Challenges From Executive Functioning in Youth With Down Syndrome
    Soltani A, Fidler DJ, Patel L, Voth K, Esbensen AJ
    Am J Intellect Dev Disabil, 2025 Mar 01;130(2):146-162.
    PMID: 39999868 DOI: 10.1352/1944-7558-130.2.146
    This study explored how caregiver-reported executive functioning domains, assessed by the BRIEF2 at baseline, predicted behavioral challenges reported by caregivers using the CBCL six months later. The sample included 94 youth with Down syndrome, aged 6 to 18 years. Results of hierarchical regression analyses revealed that, after controlling for the effect of IQ, working memory significantly predicted inattentive behaviors, inhibition significantly predicted rule-breaking behaviors, and both inhibition and emotional control significantly predicted aggressive and externalizing behaviors. After controlling for baseline behaviors, only working memory persisted as a significant predictor of inattentive behaviors measured six months later. The findings are discussed by referring to the relevant theories and research and providing clinical implications and recommendations for further studies.
    Matched MeSH terms: Aggression/physiology; Child Behavior/physiology
  6. Different threshold responses in spontaneously changing postagrogenic forest and unmanaged grassland. Shifts in small mammal populations and communities triggered by an extraordinary drought
    Shchipanov NA, Tumasian PA, Kuptsov AV, Raspopova AA, Kasatkin MV, Kalinin AA, et al.
    Environ Monit Assess, 2025 Feb 04;197(3):234.
    PMID: 39903331 DOI: 10.1007/s10661-025-13694-3
    Due to their resilience, various biological systems under environmental changes typically exhibit nonlinear responses with sudden, abrupt shifts. Although such shifts are theoretically expected, few studies traced state-and-transition dynamics in nature (Liu et al., Science 317:1513-1516, 2007). We analysed 18 years' data to trace biomass patterns, species assemblages and small mammals' population trajectories in spontaneously growing forest on formerly ploughed field, hereafter, the postagrogenic forest, and in unmanaged former pasture, hereafter, the grassland. The clear response at individual, populational and ecosystem scales triggered by extraordinary 2010 drought was observed. In the postagrogenic forest, transitioning to the historical ecosystem state, we found a shift from the grassland type of the small mammals' biomass pattern to the forest type with the abrupt reorganisation of the small mammals' community. In the grassland, a relatively steady novel ecosystem, we revealed only a long-term diminishing of total small mammals' biomass, i.e. a regime shift, while maintaining the same functional structure. The changes were based on population response. The bank vole did not show any population reaction, which testifies the ability of individuals to tolerate the drought. The common shrew experienced a population depression, which in postagrogenic forest resulted in the regimen shift after recovery, but in the grassland in only temporal decline with following return to the initial state. The root vole showed a delayed population response with the general decline of population in the grassland, and population collapse in the postagrogenic forest. Therefore, the same impact triggered various responses among different species and resulted in different effects in the successional and steady ecosystems.
    Matched MeSH terms: Arvicolinae/physiology; Shrews/physiology
  7. Mechano-responses of quadriceps muscles evoked by transcranial magnetic stimulation
    Zakaria Z, Mazlan M, Chung TY, Selvanayagam VS, Temesi J, Magenthran V, et al.
    Biomed Tech (Berl), 2025 Feb 25;70(1):3-10.
    PMID: 39320241 DOI: 10.1515/bmt-2023-0501
    Mechanomyography (MMG) may be used to quantify very small motor responses resulting from muscle activation, voluntary or involuntary. The purpose of this study was to investigate the MMG mean peak amplitude (MPA) and area under the curve (AUC) and the corresponding mechanical responses following delivery of transcranial magnetic stimulation (TMS) to the knee extensors. Fourteen adults (23 ± 1 years) received single TMS pulses at intensities from 30-80 % maximum stimulator output to elicit muscle responses in the relaxed knee extensors while seated. An accelerometer-based sensor was placed on the rectus femoris (RF) and vastus lateralis (VL) muscle bellies to measure the MMG signal. Pearson correlation revealed a positive linear relationship between MMG MPA and TMS intensity for RF (r=0.569; p<0.001) and VL (r=0.618; p<0.001). TMS intensity of ≥60 % maximum stimulator output produced significantly higher MPA than at 30 % TMS intensity and evoked measurable movement at the knee joint. MMG MPA was positively correlated to AUC (r=0.957 for RF and r=0.603 for VL; both p<0.001) and knee extension angle (r=0.596 for RF and r=0.675 for VL; both p<0.001). In conclusion, MMG captured knee extensor mechanical responses at all TMS intensities with the response increasing with increasing TMS intensity. These findings suggest that MMG can be an additional tool for assessing muscle activation.
    Matched MeSH terms: Knee Joint/physiology; Evoked Potentials, Motor/physiology
  8. Impact of combined high-intensity bodyweight interval training and breathing exercise on cardiometabolic health in normal-weight middle-aged adults with hypertension
    Herawati I, Mat Ludin AF, Ishak I, Mutalazimah M, Farah NMF
    BMC Public Health, 2025 Mar 11;25(1):962.
    PMID: 40069690 DOI: 10.1186/s12889-025-22139-y
    BACKGROUND: High-intensity interval training and breathing exercises alone have well-documented health benefits in people with hypertension. This study aimed to investigated the effects of combining the two methods on physical health among adults with hypertension.

    METHODS: Ninety-six adults (59.4 ± 9.1 years; 84% female; BMI 22.7 ± 1.6 kg/m2) with hypertension were randomized into one of four groups: Breathing Exercise (BE), High-Intensity Bodyweight Interval Training (HIBIT), Combined Exercise (CE), or a Non-Exercise Control (CON) group. The intervention lasted 10 weeks, with all exercise groups having the same total training time of 3 days per week (BE: 30 min/day; HIBIT: 60 min/day; CE: BE 30 min/day plus HIBIT 60 min/day). Resting heart rate, resting blood pressure, hand grip strength, cardiorespiratory fitness assessed using 6-Minute Walking Test (6MWT) and blood lipids were measured pre- and post-intervention.

    RESULTS: The BE group showed the greatest reduction in systolic blood pressure (SBP) compared to CON, although differences among the exercise groups were not statistically significant. The increase in 6MWT values in the combined exercise group differed significantly compared to the other three groups (p = 0.000 and effect size = 0.296). The combined exercise group showed significant reductions in total cholesterol, LDL and triglyceride levels compared to the control group. The average reduction in total cholesterol levels was 20.8 mg/dL (95% C: -41.9 - 0.4) with an effect size of 0.103. Meanwhile, the decrease in LDL and triglyceride levels was 20.1 mg/dL (95% CI: -37.6--2.5; p = 0.014) and -40.4 mg/dL (95% CI: -82.1-1.3; p = 0.04) with effect sizes of 0.118 and 0.101.

    CONCLUSIONS: In conclusion combined exercise for 10 weeks could lower systolic and diastolic blood pressure, increase CRF, and improved lipid profile. As a clinical implication, the results of this study can be an alternative or complementary approach to treatment for hypertension, potentially reducing the need for medications and their associated side effects.

    TRIAL REGISTRATION: TCTR20230707003 ( http://www.

    CLINICALTRIALS: in.th/ ) registered on 28 January 2023.

    Matched MeSH terms: Heart Rate/physiology; Cardiorespiratory Fitness/physiology
  9. 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
  10. The microscopic biological response of human chondrocytes to bovine bone scaffold
    Abdullah B, Shibghatullah AH, Hamid SS, Omar NS, Samsuddin AR
    Cell Tissue Bank, 2009 Aug;10(3):205-13.
    PMID: 18975136 DOI: 10.1007/s10561-008-9111-2
    This study was performed to determine the microscopic biological response of human nasal septum chondrocytes and human knee articular chondrocytes placed on a demineralized bovine bone scaffold. Both chondrocytes were cultured and seeded onto the bovine bone scaffold with seeding density of 1 x 105 cells per 100 microl/scaffold and incubated for 1, 2, 5 and 7 days. Proliferation and viability of the cells were measured by mitochondrial dehydrogenase activity (MTT assay), adhesion study was analyzed by scanning electron microscopy and differentiation study was analyzed by immunofluorescence staining and confocal laser scanning electron microscopy. The results showed good proliferation and viability of both chondrocytes on the scaffolds from day 1 to day 7. Both chondrocytes increased in number with time and readily grew on the surface and into the open pores of the scaffold. Immunofluorescence staining demonstrated collagen type II on the scaffolds for both chondrocytes. The results showed good cells proliferation, attachment and maturity of the chondrocytes on the demineralized bovine bone scaffold. The bovine bone being easily resourced, relatively inexpensive and non toxic has good potential for use as a three dimensional construct in cartilage tissue engineering.
    Matched MeSH terms: Cartilage/physiology*; Cell Differentiation/physiology; Cell Survival/physiology; Osteogenesis/physiology*; Chondrocytes/physiology*
  11. Fulltext A System for True and False Memory Prediction Based on 2D and 3D Educational Contents and EEG Brain Signals
    Bamatraf S, Hussain M, Aboalsamh H, Qazi EU, Malik AS, Amin HU, et al.
    Comput Intell Neurosci, 2016;2016:8491046.
    PMID: 26819593 DOI: 10.1155/2016/8491046
    We studied the impact of 2D and 3D educational contents on learning and memory recall using electroencephalography (EEG) brain signals. For this purpose, we adopted a classification approach that predicts true and false memories in case of both short term memory (STM) and long term memory (LTM) and helps to decide whether there is a difference between the impact of 2D and 3D educational contents. In this approach, EEG brain signals are converted into topomaps and then discriminative features are extracted from them and finally support vector machine (SVM) which is employed to predict brain states. For data collection, half of sixty-eight healthy individuals watched the learning material in 2D format whereas the rest watched the same material in 3D format. After learning task, memory recall tasks were performed after 30 minutes (STM) and two months (LTM), and EEG signals were recorded. In case of STM, 97.5% prediction accuracy was achieved for 3D and 96.6% for 2D and, in case of LTM, it was 100% for both 2D and 3D. The statistical analysis of the results suggested that for learning and memory recall both 2D and 3D materials do not have much difference in case of STM and LTM.
    Matched MeSH terms: Brain/physiology*; Memory, Short-Term/physiology; Pattern Recognition, Visual/physiology*; Mental Recall/physiology*; Brain Waves/physiology*
  12. Fulltext A pantropically introduced tree is followed by specific ectomycorrhizal symbionts due to pseudo-vertical transmission
    Séne S, Selosse MA, Forget M, Lambourdière J, Cissé K, Diédhiou AG, et al.
    ISME J, 2018 06;12(7):1806-1816.
    PMID: 29535364 DOI: 10.1038/s41396-018-0088-y
    Global trade increases plant introductions, but joint introduction of associated microbes is overlooked. We analyzed the ectomycorrhizal fungi of a Caribbean beach tree, seagrape (Coccoloba uvifera, Polygonacaeae), introduced pantropically to stabilize coastal soils and produce edible fruits. Seagrape displays a limited symbiont diversity in the Caribbean. In five regions of introduction (Brazil, Japan, Malaysia, Réunion and Senegal), molecular barcoding showed that seagrape mostly or exclusively associates with Scleroderma species (Basidiomycota) that were hitherto only known from Caribbean seagrape stands. An unknown Scleroderma species dominates in Brazil, Japan and Malaysia, while Scleroderma bermudense exclusively occurs in Réunion and Senegal. Population genetics analysis of S. bermudense did not detect any demographic bottleneck associated with a possible founder effect, but fungal populations from regions where seagrape is introduced are little differentiated from the Caribbean ones, separated by thousands of kilometers, consistently with relatively recent introduction. Moreover, dry seagrape fruits carry Scleroderma spores, probably because, when drying on beach sand, they aggregate spores from the spore bank accumulated by semi-hypogeous Scleroderma sporocarps. Aggregated spores inoculate seedlings, and their abundance may limit the founder effect after seagrape introduction. This rare pseudo-vertical transmission of mycorrhizal fungi likely contributed to efficient and repeated seagrape/Scleroderma co-introductions.
    Matched MeSH terms: Basidiomycota/physiology*; Spores, Fungal/physiology; Trees/physiology; Seedlings/physiology; Mycorrhizae/physiology*
  13. Fulltext Gap-induced inhibition of the post-auricular muscle response in humans and guinea pigs
    Wilson CA, Berger JI, de Boer J, Sereda M, Palmer AR, Hall DA, et al.
    Hear Res, 2019 03 15;374:13-23.
    PMID: 30685571 DOI: 10.1016/j.heares.2019.01.009
    A common method for measuring changes in temporal processing sensitivity in both humans and animals makes use of GaP-induced Inhibition of the Acoustic Startle (GPIAS). It is also the basis of a common method for detecting tinnitus in rodents. However, the link to tinnitus has not been properly established because GPIAS has not yet been used to objectively demonstrate tinnitus in humans. In guinea pigs, the Preyer (ear flick) myogenic reflex is an established method for measuring the acoustic startle for the GPIAS test, while in humans, it is the eye-blink reflex. Yet, humans have a vestigial remnant of the Preyer reflex, which can be detected by measuring skin surface potentials associated with the Post-Auricular Muscle Response (PAMR). A similar electrical potential can be measured in guinea pigs and we aimed to show that the PAMR could be used to demonstrate GPIAS in both species. In guinea pigs, we compare the GPIAS measured using the pinna movement of the Preyer reflex and the electrical potential of the PAMR to demonstrate that the two are at least equivalent. In humans, we establish for the first time that the PAMR provides a reliable way of measuring GPIAS that is a pure acoustic alternative to the multimodal eye-blink reflex. Further exploratory tests showed that while eye gaze position influenced the size of the PAMR response, it did not change the degree of GPIAS. Our findings confirm that the PAMR is a sensitive method for measuring GPIAS and suggest that it may allow direct comparison of temporal processing between humans and animals and may provide a basis for an objective test of tinnitus.
    Matched MeSH terms: Auditory Pathways/physiology; Blinking/physiology; Reflex, Startle/physiology*; Muscle, Skeletal/physiology; Ear Auricle/physiology*
  14. Fulltext Cortical signal-in-noise coding varies by noise type, signal-to-noise ratio, age, and hearing status
    Maamor N, Billings CJ
    Neurosci Lett, 2017 01 01;636:258-264.
    PMID: 27838448 DOI: 10.1016/j.neulet.2016.11.020
    The purpose of this study was to determine the effects of noise type, signal-to-noise ratio (SNR), age, and hearing status on cortical auditory evoked potentials (CAEPs) to speech sounds. This helps to explain the hearing-in-noise difficulties often seen in the aging and hearing impaired population. Continuous, modulated, and babble noise types were presented at varying SNRs to 30 individuals divided into three groups according to age and hearing status. Significant main effects of noise type, SNR, and group were found. Interaction effects revealed that the SNR effect varies as a function of noise type and is most systematic for continuous noise. Effects of age and hearing loss were limited to CAEP latency and were differentially modulated by energetic and informational-like masking. It is clear that the spectrotemporal characteristics of signals and noises play an important role in determining the morphology of neural responses. Participant factors such as age and hearing status, also play an important role in determining the brain's response to complex auditory stimuli and contribute to the ability to listen in noise.
    Matched MeSH terms: Auditory Cortex/physiology*; Auditory Perception/physiology; Evoked Potentials, Auditory/physiology*; Hearing/physiology*; Speech Perception/physiology
  15. Fulltext Over-expression of Nicotinamide phosphoribosyltransferase in mouse cells confers protective effect against oxidative and ER stress-induced premature senescence
    Nuriliani A, Nakahata Y, Ahmed R, Khaidizar FD, Matsui T, Bessho Y
    Genes Cells, 2020 Aug;25(8):593-602.
    PMID: 32533606 DOI: 10.1111/gtc.12794
    A main feature of aged organisms is the accumulation of senescent cells. Accumulated senescent cells, especially stress-induced premature senescent cells, in aged organisms lead to the decline of the regenerative potential and function of tissues. We recently reported that the over-expression of NAMPT, which is the rate-limiting enzyme in mammalian NAD+ salvage pathway, delays replicative senescence in vitro. However, whether Nampt-overexpressing cells are tolerant of stress-induced premature senescence remains unknown. Here, we show that primary mouse embryonic fibroblasts derived from Nampt-overexpressing transgenic mice (Nampt Tg-MEF cells) possess resistance against stress-induced premature senescence in vitro. We found that higher oxidative or endoplasmic reticulum (ER) stress is required to induce premature senescence in Nampt Tg-MEF cells compared to wild-type cells. Moreover, we found that Nampt Tg-MEF cells show acute expression of unfolded protein response (UPR)-related genes, which in turn would have helped to restore proteostasis and avoid cellular senescence. Our results demonstrate that NAMPT/NAD+ axis functions to protect cells not only from replicative senescence, but also from stress-induced premature senescence in vitro. We anticipate that in vivo activation of NAMPT activity or increment of NAD+ would protect tissues from the accumulation of premature senescent cells, thereby maintaining healthy aging.
    Matched MeSH terms: Antioxidants/physiology; Cell Aging/physiology*; Oxidative Stress/physiology; Cell Proliferation/physiology; Endoplasmic Reticulum Stress/physiology
  16. Orthostatic blood pressure changes and physical, functional and cognitive performance: the MELoR study
    Saedon NI, Frith J, Goh CH, Ahmad WAW, Khor HM, Tan KM, et al.
    Clin Auton Res, 2020 04;30(2):129-137.
    PMID: 31696333 DOI: 10.1007/s10286-019-00647-3
    PURPOSE: Consensus definitions currently define initial orthostatic hypotension (IOH) as ≥ 40 mmHg systolic (SBP) or ≥ 20 mmHg in diastolic blood pressure (DBP) reductions within 15 s of standing, while classical orthostatic hypotension (COH) is defined as a sustained reduction ≥ 20 mmHg SBP or ≥ 10 mmHg SBP within 3 min of standing. The clinical relevance of the aforementioned criteria remains unclear. The present study aimed to determine factors influencing postural blood pressure changes and their relationship with physical, functional and cognitive performance in older adults.

    METHODS: Individuals aged ≥ 55 years were recruited through the Malaysian Elders Longitudinal Research (MELoR) study and continuous non-invasive BP was monitored over 5 min of supine rest and 3 min of standing. Physical performance was measured using the timed-up-and-go test, functional reach, handgrip and Lawton's functional ability scale. Cognition was measured with the Montreal Cognitive Assessment. Participants were categorized according to BP responses into four categories according to changes in SBP/DBP reductions from supine to standing:

    Matched MeSH terms: Blood Pressure/physiology*; Cognition/physiology*; Postural Balance/physiology; Psychomotor Performance/physiology*; Hand Strength/physiology*
  17. Inhibition of calcium-dependent contractions of the isolated guinea-pig ileal longitudinal muscle and taenia coli by the total glycosidic extract of the plant Sarcolobus globosus
    Mustafa MR
    Toxicon, 1993 Jan;31(1):67-74.
    PMID: 8446965
    The effect of the total glysosidic extract of the plant Sarcolobus globosus was investigated on the contractions of the smooth muscle of the guinea-pig ileal longitudinal muscle and taenia coli. In the ileal longitudinal muscle, addition of the extract inhibited the electrical field-stimulated twitches. Similarly to verapamil, it also reduced the contractions of the muscle to acetylcholine, histamine and KCl. However, only the tonic contraction to KCl was reversed by increasing the extracellular calcium concentration. In the taenia coli, lower concentrations of both the extract and verapamil induced a parallel displacement of the dose-response curves to calcium (0.30-30 mM). Addition of the extract also dose-dependently inhibited the KCl-induced contraction of the taenia coli. Increasing the calcium concentration increased the IC50 values of the extract. The result suggests that the inhibitory effect of the Sarcolobus globosus extract on the smooth muscle, like verapamil, is mainly due to inhibition of calcium influx.
    Matched MeSH terms: Calcium/physiology*; Colon/physiology; Ileum/physiology; Intestines/physiology; Muscle, Smooth/physiology
  18. Delayed liver regeneration in C3H/HeJ mice: possible involvement of haemodynamic and structural changes in the hepatic microcirculation
    Marlini M, Mabuchi A, Mallard BL, Hairulhisyam N, Akashi-Takamura S, Harper JL, et al.
    Exp Physiol, 2016 12 01;101(12):1492-1505.
    PMID: 27634415 DOI: 10.1113/EP085727
    NEW FINDINGS: What is the central question of this study? The liver regenerative process is complex and involves a sequence of signalling events, but the possible involvement of structural and haemodynamic changes in vivo during this process has never been explored. What is the main finding and its importance? Normal sinusoidal blood flow and velocity are crucial for a normal regenerative response, and delays in these haemodynamic events resulted in impaired liver regeneration in lipopolysaccharide-insensitive, C3H/HeJ mice. Toll-like receptor 4 signalling is required for restoration of normal liver architecture during the liver regenerative process. Liver regeneration is delayed in mice with a defective Toll-like receptor 4 (TLR4; C3H/HeJ mice) but is normal in TLR4 knockouts (TLR4-/- ). Here, we investigated the possible involvement of structural and haemodynamic changes in vivo in the underlying mechanism. In lipopolysaccharide-sensitive (C3H/HeN and C57BL/6) and lipopolysaccharide-insensitive (C3H/HeJ and TLR4-/- ) mice, a 70% partial hepatectomy (PH) was performed under inhalational anaesthesia. At days 3 and 7 after PH, the hepatic microcirculation was interrogated using intravital microscopy. Delayed liver regeneration was confirmed in C3H/HeJ, but not in C3H/HeN, C57BL/6 (WT) or TLR4-/- mice by liver weight-to-body-weight ratio, the percentage of proliferating cell nuclear antigen (PCNA)-positive cells and mitotic index data. At day 3 after PH, sinusoidal red blood cell velocity increased by 100% in C3H/HeN mice, but by only 40% in C3H/HeJ mice. Estimated sinusoidal blood flow was significantly higher at day 7 after PH in C3H/HeN than in C3H/HeJ mice. The hepatic cord width was significantly larger in C3H/HeN than in C3H/HeJ mice at day 3 and it was significantly larger in TLR4-/- than in C57BL/6 WT mice at day 7 after PH. Hepatocyte nucleus density and functional sinusoidal density was significantly reduced at days 3 and 7 after PH in all mouse strains compared with their zero-time controls. Functional sinusoidal density was significantly lower in C3H/HeJ compared with C3H/HeN mice at day 7 after PH. The present study indicates that altered sinusoidal blood flow and velocity in C3H/HeJ mice may contribute to the observed delay in the regenerative response in these mice. In addition, restoration of normal liver architecture may be delayed in TLR4-/- mice.
    Matched MeSH terms: Hemodynamics/physiology*; Liver/physiology*; Liver Regeneration/physiology*; Microcirculation/physiology*; Hepatocytes/physiology
  19. New concepts in primate production. Report on the Battelle Seattle Research Center Conference, August 11-12, 1972
    Bermant G, Lindburg DS
    J Med Primatol, 1973;2(6):324-40.
    PMID: 4151881
    Matched MeSH terms: Haplorhini/physiology; Pan troglodytes/physiology; Macaca/physiology; Papio/physiology; Primates/physiology*
  20. Magnetic nanoparticles are highly toxic to chloroquine-resistant Plasmodium falciparum, dengue virus (DEN-2), and their mosquito vectors
    Murugan K, Wei J, Alsalhi MS, Nicoletti M, Paulpandi M, Samidoss CM, et al.
    Parasitol Res, 2017 Feb;116(2):495-502.
    PMID: 27815736 DOI: 10.1007/s00436-016-5310-0
    A main challenge in parasitology is the development of reliable tools to prevent or treat mosquito-borne diseases. We investigated the toxicity of magnetic nanoparticles (MNP) produced by Magnetospirillum gryphiswaldense (strain MSR-1) on chloroquine-resistant (CQ-r) and sensitive (CQ-s) Plasmodium falciparum, dengue virus (DEN-2), and two of their main vectors, Anopheles stephensi and Aedes aegypti, respectively. MNP were studied by Fourier-transform infrared spectroscopy and transmission electron microscopy. They were toxic to larvae and pupae of An. stephensi, LC50 ranged from 2.563 ppm (1st instar larva) to 6.430 ppm (pupa), and Ae. aegypti, LC50 ranged from 3.231 ppm (1st instar larva) to 7.545 ppm (pupa). MNP IC50 on P. falciparum were 83.32 μg ml(-1) (CQ-s) and 87.47 μg ml(-1) (CQ-r). However, the in vivo efficacy of MNP on Plasmodium berghei was low if compared to CQ-based treatments. Moderate cytotoxicity was detected on Vero cells post-treatment with MNP doses lower than 4 μg ml(-1). MNP evaluated at 2-8 μg ml(-1) inhibited DEN-2 replication inhibiting the expression of the envelope (E) protein. In conclusion, our findings represent the first report about the use of MNP in medical and veterinary entomology, proposing them as suitable materials to develop reliable tools to combat mosquito-borne diseases.
    Matched MeSH terms: Aedes/physiology; Anopheles/physiology; Dengue Virus/physiology; Plasmodium falciparum/physiology; Mosquito Vectors/physiology
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