Displaying publications 161 - 180 of 370 in total

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  1. Huang C, Yu W, Xu Z, Qiu Y, Chen M, Qiu B, et al.
    Int J Biol Sci, 2014;10(2):200-11.
    PMID: 24550688 DOI: 10.7150/ijbs.7301
    Three distinct bamboo bat species (Tylonycteris) are known to inhabit tropical and subtropical areas of Asia, i.e., T. pachypus, T. robustula, and T. pygmaeus. This study performed karyotypic examinations of 4 specimens from southern Chinese T. p. fulvidus populations and one specimen from Thai T. p. fulvidus population, which detected distinct karyotypes (2n=30) compared with previous karyotypic descriptions of T. p. pachypus (2n=46) and T. robustula (2n=32) from Malaysia. This finding suggested a cryptic Tylonycteris species within T. pachypus complex in China and Thailand. Morphometric studies indicated the difficulty in distinguishing the cryptic species and T. p. pachypus from Indonesia apart from the external measurements, which might be the reason for their historical misidentification. Based on 623 bp mtDNA COI segments, a phylogeographic examination including T. pachypus individuals from China and nearby regions, i.e., Vietnam, Laos, and Cambodia, was conducted to examine the population genetic structure. Genealogical and phylogeographical results indicated that at least two diverged lineages existed in these regions (average 3.4 % of Kimura 2-parameter distances) and their population structure did not match the geographic pattern. These results suggested that at least two historical colonizations have occurred by the cryptic species. Furthermore, through integration of traditional and geometric morphological results, morphological differences on zygomatic arches, toothrows and bullae were detected between two lineages in China. Given the similarity of vegetation and climate of Guangdong and Guangxi regions, we suggested that such differences might be derived from their historical adaptation or distinct evolutionary history rather than the differences of habitats they occurred currently.
  2. Dong L, Li Y, Chen Q, Liu Y, Qiao Z, Sang S, et al.
    Food Chem, 2023 Aug 15;417:135861.
    PMID: 36906946 DOI: 10.1016/j.foodchem.2023.135861
    Advanced glycosylation end products (AGEs) are a series of complex compounds which generate in the advanced phase of Maillard reaction, which can pose a non-negligible risk to human health. This article systematically encompasses AGEs in milk and dairy products under different processing conditions, influencing factors, inhibition mechanism and levels among the different categories of dairy products. In particular, it describes the effects of various sterilization techniques on the Maillard reaction. Different processing techniques have a significant effect on AGEs content. In addition, it clearly articulates the determination methods of AGEs and even discusses its immunometabolism via gut microbiota. It is observed that the metabolism of AGEs can affect the composition of the gut microbiota, which further has an impact on intestinal function and the gut-brain axis. This research also provides a suggestion for AGEs mitigation strategies, which are beneficial to optimize the dairy production, especially innovative processing technology application.
  3. Yazawa K, Kurokawa M, Obuchi M, Li Y, Yamada R, Sadanari H, et al.
    Antivir Chem Chemother, 2011;22(1):1-11.
    PMID: 21860068 DOI: 10.3851/IMP1782
    We examined the anti-influenza virus activity of tricin, 4',5,7-trihydroxy-3',5'-dimethoxyflavone, against five viruses: A/Solomon islands/3/2006 (H1N1), A/Hiroshima/52/2005 (H3N2), A/California/07/2009 (H1N1pdm), A/Narita/1/2009 (H1N1pdm) and B/Malaysia/2506/2004 strains in vitro and against A/PR/8/34 virus in vivo.
  4. Lu B, Zhang C, Deng DR, Weng JC, Song JX, Fan XH, et al.
    Molecules, 2023 Oct 28;28(21).
    PMID: 37959733 DOI: 10.3390/molecules28217314
    Sodium-ion batteries (SIBs) are promising alternatives to replace lithium-ion batteries as future energy storage batteries because of their abundant sodium resources, low cost, and high charging efficiency. In order to match the high energy capacity and density, designing an atomically doped carbonous material as the anode is presently one of the important strategies to commercialize SIBs. In this work, we report the preparation of high-performance dual-atom-doped carbon (C) materials using low-cost corn starch and thiourea (CH4N2S) as the precursors. The electronegativity and radii of the doped atoms and C are different, which can vary the embedding properties of sodium ions (Na+) into/on C. As sulfur (S) can effectively expand the layer spacing, it provides more channels for embedding and de-embedding Na+. The synergistic effect of N and S co-doping can remarkably boost the performance of SIBs. The capacity is preserved at 400 mAh g -1 after 200 cycles at 500 mA g-1; more notably, the initial Coulombic efficiency is 81%. Even at a high rate of high current of 10 A g-1, the cell capacity can still reach 170 mAh g-1. More importantly, after 3000 cycles at 1 A g-1, the capacity decay is less than 0.003% per cycle, which demonstrates its excellent electrochemical performance. These results indicate that high-performance carbon materials can be prepared using low-cost corn starch and thiourea.
  5. Liu Y, Yan N, Chen Q, Dong L, Li Y, Weng P, et al.
    PMID: 37552798 DOI: 10.1080/10408398.2023.2239350
    Citrus polyphenols can modulate gut microbiota and such bi-directional interaction that can yield metabolites such as short-chain fatty acids (SCFAs) to aid in gut homeostasis. Such interaction provides citrus polyphenols with powerful prebiotic potential, contributing to guts' health status and metabolic regulation. Citrus polyphenols encompass unique polymethoxy flavonoids imparting non-polar nature that improve their bioactivities and ability to penetrate the blood-brain barrier. Green extraction technology targeting recovery of these polyphenols has received increasing attention due to its advantages of high extraction yield, short extraction time, low solvent consumption, and environmental friendliness. However, the low bioavailability of citrus polyphenols limits their applications in extraction from citrus by-products. Meanwhile, nano-encapsulation technology may serve as a promising approach to improve citrus polyphenols' bioavailability. As citrus polyphenols encompass multiple hydroxyl groups, they are potential to interact with bio-macromolecules such as proteins and polysaccharides in nano-encapsulated systems that can improve their bioavailability. This multifaceted review provides a research basis for the green and efficient extraction techniques of citrus polyphenols, as well as integrated mechanisms for its anti-inflammation, alleviating metabolic syndrome, and regulating gut homeostasis, which is more capitalized upon using nano-delivery systems as discussed in that review to maximize their health and food applications.
  6. Li Y, Vogel C, Kalinichenko LS, Hübner H, Weikert D, Schaefer N, et al.
    Addict Biol, 2023 Aug;28(8):e13305.
    PMID: 37500485 DOI: 10.1111/adb.13305
    Alcohol consumption is a widespread behaviour that may eventually result in the development of alcohol use disorder (AUD). Alcohol, however, is rarely consumed in pure form but in fruit- or corn-derived preparations, like beer. These preparations add other compounds to the consumption, which may critically modify alcohol intake and AUD risk. We investigated the effects of hordenine, a barley-derived beer compound on alcohol use-related behaviours. We found that the dopamine D2 receptor agonist hordenine (50 mg/kg) limited ongoing alcohol consumption and prophylactically diminished relapse drinking after withdrawal in mice. Although not having reinforcing effects on its own, hordenine blocked the establishment of alcohol-induced conditioned place preference (CPP). However, it independently enhanced alcohol CPP retrieval. Hordenine had a dose-dependent inhibitory effect on locomotor activity. Chronic hordenine exposure enhanced monoamine tissue levels in many brain regions. Further characterization revealed monoaminergic binding sites of hordenine and found a strong binding on the serotonin and dopamine transporters, and dopamine D3 , and adrenergic α1A and α2A receptor activation but no effects on GABAA receptor or glycinergic signalling. These findings suggest that natural ingredients of beer, like hordenine, may work as an inhibitory and use-regulating factor by their modulation of monoaminergic signalling in the brain.
  7. Yang B, Wang Q, Li Y, Li L, Zhang Y, Leong Bin Abdullah MFI, et al.
    PLoS One, 2023;18(4):e0282488.
    PMID: 37099528 DOI: 10.1371/journal.pone.0282488
    OBJECTIVE: The present study opted for the adrenal phaeochromocytoma (PC12) cell line to frame a neuronal injury model induced by alcohol exposure in vitro, aiming to probe whether TAp73 and miR-96-5p are involved in the neuronal injury process induced by alcohol and elucidate the regulatory relationship between miR-96-5p and TAp73.

    METHODS: Immunofluorescence staining was used to observe the structural features of PC12 cells after culturing in medium with nerve growth factor (NGF). After different doses and different durations of alcohol treatment, CCK-8 assay was performed to detect the viability of PC12 cells, flow cytometry assay was carried out to detect the apoptosis rate of PC12 cells, dual-luciferase reporter assay was used to definitude the regulatory relationship between miR-96-5p and Tp73, and western blot was used to detect the protein expression of TAp73.

    RESULTS: The result of immunofluorescence staining demonstrated that PC12 cells abundantly expressed Map2, CCK-8 assay illustrated alcohol exposure significantly downregulated the cell viability of PC12 cells, Treatment with miR-96-5p inhibitor induced apoptosis and upregulated the expression of TAp73 in PC12 cells. Contrastingly, miR-96-5p mimic reversed the above effects and downregulation of TAp73 inhibited the apoptosis of PC12 cells.

    CONCLUSION: The present study demonstrated that miR-96-5p participates in alcohol-induced apoptosis in PC12 cells via negatively regulating TAp73.

  8. Li Y, Dong W, Zhang L, Yang Y, Song Y, Shi N, et al.
    Aesthet Surg J, 2024 Jan 25.
    PMID: 38271268 DOI: 10.1093/asj/sjae010
    BACKGROUND: Large and long ears are regarded as symbols of wealth and health in eastern Asian culture, patients with lying ears wish their ears to be more exposed and prominent. Surgeries correcting lying ears have been documented.

    OBJECTIVES: We report correction of lying ears and aesthetic modification of helix and ear lobule with HA injections.

    METHODS: We performed HA injections at auriculocephalic sulcus (AS) to increase cranioauricular angle (CA) and correct lying ears. The injections at helix and lobule were case-specific. The CA was measured and photographs were taken at baseline and 1-, 3-, 6-, and 10-month follow-ups. Efficacy was assessed using a 5-point global aesthetic improvement scale (GAIS). Adverse events (AEs) were recorded.

    RESULTS: Forty-six patients (92 ears) received HA injections and completed follow-ups. Instant correction outcomes were observed. Sixteen (34.8%) patients received one touch-up injection, whose clinical efficacy persisted for 1 to 1.5 years. The GAIS for over 90% of cases with touch-up treatment was "very much improved" or "much improved" at all follow-ups. The GAIS for over 70% of cases without touch-up treatment was "very much improved" or "much improved" at 1, 3, and 6-month follow-ups. CA increased significantly compared with the baseline. Patients also reported "more V-shaped face shape" and "lifted jawline" effects. No serious AEs occurred.

    CONCLUSIONS: As an alternative technique to surgeries, HA filler injections at AS effectively corrected lying ears. This technique produced immediate, long-lasting, and aesthetically pleasing results. The side effects and downtime were minimal.

  9. Zhang J, Zhong L, Wang P, Song J, Shi C, Li Y, et al.
    Foods, 2024 Jan 22;13(2).
    PMID: 38275709 DOI: 10.3390/foods13020342
    Flavor is a crucial parameter for assessing the sensory quality of yak milk. However, there is limited information regarding the factors influencing its taste. In this study, the effects of endogenous lipoprotein lipase (LPL) on the volatile flavor components of yak milk under storage conditions of 4 °C, 18 °C and 65 °C were analyzed via headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with orthogonal partial least-squares (OPSL) discrimination, and the reasons for the changes in yak milk flavors were investigated. Combined with the difference in the changes in volatile flavor substance before and after the action of LPL, LPL was found to have a significant effect on the flavor of fresh yak milk. Fresh milk was best kept at 4 °C for 24 h and pasteurized for more than 24 h. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were employed to characterize the volatile components in yak milk under various treatment conditions. Twelve substances with significant influence on yak milk flavor were identified by measuring their VIP values. Notably, 2-nonanone, heptanal, and ethyl caprylate exhibited OAV values greater than 1, indicating their significant contribution to the flavor of yak milk. Conversely, 4-octanone and 2-heptanone displayed OAV values between 0.1 and 1, showing their important role in modifying the flavor of yak milk. These findings can serve as monitoring indicators for assessing the freshness of yak milk.
  10. Hamid HA, Lin X, Qin YK, Akim AM, Zhang L, Wang J, et al.
    Int Wound J, 2024 Feb;21(2):e14574.
    PMID: 38379231 DOI: 10.1111/iwj.14574
    This cross-sectional study was conducted to examine the most effective strategies for managing malodorous and infected wounds in patients who have been diagnosed with advanced cervical cancer. The research was conducted in Liupanshui, China. The study specifically examined demographic profiles, wound characteristics and effectiveness of wound management approaches. The study incorporated the heterogeneous sample of 289 participants who fulfilled the inclusion criteria. Data collection was conducted via structured questionnaires and medical record evaluations. Descriptive statistics and statistical analyses, such as regression analysis, were utilized to evaluate demographic attributes, wound profiles and effects of different approaches to wound management. The findings unveiled the heterogeneous demographic composition of patients, encompassing differences in socioeconomic standing, educational attainment and age. A wide range of wound characteristics were observed, as 65.7% of lesions during the acute phase with diameter between 2 and 5 centimetres, while 41.5% of lesions had this range. The most prevalent types of infections were those caused by fungi (48.4%), followed by bacterial infections lacking resistance (38.1%). A moderate degree of odour intensity was prevalent, affecting 45.0% of the cases. With maximal odour reduction of 80%, a mean healing time of 25 days and patient satisfaction rating of 4.5 out of 5, Negative Pressure Wound Therapy demonstrated itself to be the most efficacious treatment method. Additional approaches, such as photodynamic therapy and topical antibiotic therapy, demonstrated significant effectiveness, as evidenced by odour reductions of 70% and 75%, respectively, and patient satisfaction ratings of 4.3 and 4.2. Thus, the study determined challenges associated with management of malodorous and infected lesions among patients with advanced cervical cancer. The results underscored the significance of individualized care approaches, drew attention to efficacious wound management techniques and identified critical determinants that impacted patient recuperation. The findings of this study hold potential for advancing palliative care for individuals diagnosed with advanced cervical cancer.
  11. Tao J, Chen J, Li J, Mathurin L, Zheng JC, Li Y, et al.
    Proc Natl Acad Sci U S A, 2017 09 12;114(37):9832-9837.
    PMID: 28855335 DOI: 10.1073/pnas.1709163114
    The optimal functionalities of materials often appear at phase transitions involving simultaneous changes in the electronic structure and the symmetry of the underlying lattice. It is experimentally challenging to disentangle which of the two effects--electronic or structural--is the driving force for the phase transition and to use the mechanism to control material properties. Here we report the concurrent pumping and probing of Cu2S nanoplates using an electron beam to directly manipulate the transition between two phases with distinctly different crystal symmetries and charge-carrier concentrations, and show that the transition is the result of charge generation for one phase and charge depletion for the other. We demonstrate that this manipulation is fully reversible and nonthermal in nature. Our observations reveal a phase-transition pathway in materials, where electron-induced changes in the electronic structure can lead to a macroscopic reconstruction of the crystal structure.
  12. Dai L, Deng L, Wang W, Li Y, Wang L, Liang T, et al.
    Environ Int, 2023 Feb;172:107775.
    PMID: 36739854 DOI: 10.1016/j.envint.2023.107775
    There is a growing concern about human health of residents living in areas where mining and smelting occur. In order to understand the exposure to the potentially toxic elements (PTEs), we here identify and examine the cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn) in scalp hair of residents living in the mining area (Bayan Obo, n = 76), smelting area (Baotou, n = 57) and a reference area (Hohhot, n = 61). In total, 194 hair samples were collected from the volunteers (men = 87, women = 107) aged 5-77 years old in the three areas. Comparing median PTEs levels between the young and adults, Ni levels were significantly higher in adults living in the smelting area while Cr was highest in adults from the mining area, no significant difference was found for any of the elements in the reference area. From the linear regression model, no significant relationship between PTEs concentration, log10(PTEs), and age was found. The concentrations of Ni, Cd, and Pb in hair were significantly lower in the reference area when compared to both mining and smelting areas. In addition, Cu was significantly higher in the mining area when compared to the smelting area. Factor analysis (FA) indicated that men and women from the smelting area (Baotou) and mining area (Bayan Obo), respectively, had different underlying communality of log10(PTEs), suggesting different sources of these PTEs. Multiple factor analysis quantilized the importance of gender and location when combined with PTEs levels in human hair. The results of this study indicate that people living in mining and/or smelting areas have significantly higher PTEs (Cu, Ni, Cd, and Pb) hair levels compared to reference areas, which may cause adverse health effects. Remediation should therefore be implemented to improve the health of local residents in the mining and smelting areas.
  13. Li Y, Sun M, Tian X, Bao T, Yu Q, Ma NL, et al.
    J Nutr Biochem, 2024 Nov;133:109709.
    PMID: 39053860 DOI: 10.1016/j.jnutbio.2024.109709
    Gut microbiota dysbiosis and gut barrier disruption are key events associated with high-fat diet (HFD)-induced systemic metabolic disorders. Gymnemic acid (GA) has been reported to have an important role in alleviating HFD-induced disorders of glycolipid metabolism, but its regulatory role in HFD-induced disorders of the gut microbiota and gut barrier function has not been elucidated. Here we showed that GA intervention in HFD-induced hamsters increased the relative abundance of short-chain fatty acid (SCFA)-producing microbes including Lactobacillus (P
  14. Li X, Tiang MF, Cui X, Li Y, Wang Z, Zhao L, et al.
    Int J Biol Macromol, 2024 Nov 22;283(Pt 4):137989.
    PMID: 39581417 DOI: 10.1016/j.ijbiomac.2024.137989
    In this pioneering study, electrostatic spraying (ES) technology with high voltages is proposed to reduce the size of hydrogel microbeads further, aiming to enhance the adsorption rate of cationic methylene blue (MB) dye. The increased voltages, ranging from 0.0 to 13.0 kV, further decreased the size of electrostatically sprayed hydrogel microbeads crosslinked by hydrogen bonds between sodium alginate (SA) and carboxymethyl chitosan (CMCS) in hydrochloric acid. The size of SA/CMCS hydrogel microbeads was successfully reduced from 2000 ± 121 μm (SC-2000) to 400 ± 15 μm (SC-400). Notably, SC-400 exhibits the highest maximum adsorption capacity (qm) and rate constant (k2) at 840.3 mg/g and 0.0598 g/mg/min, respectively, at pH 9.0 and a temperature of 25 °C in the absence of ionic compounds, which is three times higher than that of SC-2000, due to their high specific surface area and pore volume. Through a series of adsorption studies and characterization analyses, SA/CMCS hydrogel microbeads displayed heterogeneous adsorption behaviors towards MB dye through electrostatic interactions between the deprotonated carboxylic groups and cationic MB molecules, where MB adsorption efficiency could be significantly influenced by pH and ionic strength. These findings suggest that ES technology is effective in synthesizing smaller SA/CMCS hydrogel microbeads with enhanced MB removal rates and stable adsorption capacities and their applications could be further explored for removing other organic dyes and toxic metals in subsequent research studies.
  15. Feng H, Qin Y, Li Y, Li S, Zheng Y, Yan J, et al.
    Clin Cosmet Investig Dermatol, 2024;17:2595-2613.
    PMID: 39600528 DOI: 10.2147/CCID.S479632
    AIM: The application of bibliometric analysis gives insights into research trend and future perspectives. This paper aims to understand the current status of studies on traditional Chinese medicine (TCM) in the treatment of atopic dermatitis (AD), and to investigate the cooperation network, hotspots and trends in the field.

    METHODS: The original data were retrieved from the Web of Science Core Collection by searching for the topic "atopic dermatitis" and "traditional Chinese medicine" with the time span of 2004-2023. Microsoft Excel was used to create statistical tables and charts, whereas CiteSpace and VOSViewer were applied for knowledge mapping.

    RESULTS: In total, 252 publications were identified and downloaded. Current research on TCM treating AD is in the steady growth period. China has the largest number of publications, whereas the USA has the greatest international influence. Notably, the Arab Emirates, Malaysia, India and Bangladesh all have a high research impact but with a low amount of publications. Universities in Hong Kong China have the largest number of publications, but their interaction with other institutions is very poor. The top three most productive authors are all from Hong Kong, having a strong collaboration network with each other. The popular research topics in this field are "children" "cell" "activation" "nf kappa b" "inflammation" "asthma" "extract" "management" and "cytokine". According to the analysis of leading co-cited journals and authors, "J ETHNOPHARMACOL" has the largest amount of citations whilst "AM J CHINESE MED" the strongest academic influence. The largest number of co-cited authors comes from "Hon Karn-Lun Ellis", a well-known scholar from Hong Kong.

    CONCLUSION: TCM has been widely used in AD treatment, honored for its individualized therapeutic concepts of evidence-based treatment. The academic community must form a continuous and deep-going pattern to achieve higher international influence and a stronger research degree in this field.

  16. Li YQ, Ghafari M, Holbrook AJ, Boonen I, Amor N, Catalano S, et al.
    bioRxiv, 2023 Jun 30.
    PMID: 37425679 DOI: 10.1101/2023.06.30.547218
    In the search for natural reservoirs of hepatitis C virus (HCV), a broad diversity of non-human viruses within the Hepacivirus genus has been uncovered. However, the evolutionary dynamics that shaped the diversity and timescale of hepaciviruses evolution remain elusive. To gain further insights into the origins and evolution of this genus, we screened a large dataset of wild mammal samples (n = 1,672) from Africa and Asia, and generated 34 full-length hepacivirus genomes. Phylogenetic analysis of these data together with publicly available genomes emphasizes the importance of rodents as hepacivirus hosts and we identify 13 rodent species and 3 rodent genera (in Cricetidae and Muridae families) as novel hosts of hepaciviruses. Through co-phylogenetic analyses, we demonstrate that hepacivirus diversity has been affected by cross-species transmission events against the backdrop of detectable signal of virus-host co-divergence in the deep evolutionary history. Using a Bayesian phylogenetic multidimensional scaling approach, we explore the extent to which host relatedness and geographic distances have structured present-day hepacivirus diversity. Our results provide evidence for a substantial structuring of mammalian hepacivirus diversity by host as well as geography, with a somewhat more irregular diffusion process in geographic space. Finally, using a mechanistic model that accounts for substitution saturation, we provide the first formal estimates of the timescale of hepacivirus evolution and estimate the origin of the genus to be about 22 million years ago. Our results offer a comprehensive overview of the micro- and macroevolutionary processes that have shaped hepacivirus diversity and enhance our understanding of the long-term evolution of the Hepacivirus genus.
  17. Li Y, Tee KK, Liao H, Hase S, Uenishi R, Li XJ, et al.
    J Acquir Immune Defic Syndr, 2010 Jun;54(2):129-36.
    PMID: 20386110 DOI: 10.1097/QAI.0b013e3181d82ce5
    A molecular epidemiological investigation conducted among injecting drug users in eastern Peninsular Malaysia in 2007 identified a cluster of sequences (n = 3) located outside any known HIV-1 genotype. Analyses of near full-length nucleotide sequences of these strains from individuals with no recognizable linkage revealed that they have an identical subtype structure comprised of CRF01_AE and subtype B', distinct from any known circulating recombinant forms (CRFs). This novel CRF, designated CRF48_01B, is closely related to CRF33_01B, previously identified in Kuala Lumpur. Phylogenetic analysis of multiple CRF48_01B genome regions showed that CRF48_01B forms a monophyletic cluster within CRF33_01B, suggesting that this new recombinant is very likely a descendant of CRF33_01B. CRF48_01B thus represents one of the first examples of a "second-generation" CRF, generated by additional crossover with pre-existing CRFs. Corroborating these results, Bayesian molecular clock analyses indicated that CRF48_01B emerged in approximately 2001, approximately approximately 8 years after the emergence of CRF33_01B.
  18. Zhang ZY, Yang WY, Dominiczak AF, Wang JG, Wu Y, Almustafa B, et al.
    Hypertension, 2019 11;74(5):1064-1067.
    PMID: 31422692 DOI: 10.1161/HYPERTENSIONAHA.119.13206
  19. Sutoko S, Chan YL, Obata A, Sato H, Maki A, Numata T, et al.
    Neurophotonics, 2019 Jan;6(1):015001.
    PMID: 30662924 DOI: 10.1117/1.NPh.6.1.015001
    Functional near-infrared spectroscopy (fNIRS) is a noninvasive functional imaging technique measuring hemodynamic changes including oxygenated (



    O


    2


    Hb

    ) and deoxygenated (HHb) hemoglobin. Low frequency (LF; 0.01 to 0.15 Hz) band is commonly analyzed in fNIRS to represent neuronal activation. However, systemic physiological artifacts (i.e., nonneuronal) likely occur also in overlapping frequency bands. We measured peripheral photoplethysmogram (PPG) signal concurrently with fNIRS (at prefrontal region) to extract the low-frequency oscillations (LFOs) as systemic noise regressors. We investigated three main points in this study: (1) the relationship between prefrontal fNIRS and peripheral PPG signals; (2) the denoising potential using these peripheral LFOs, and (3) the innovative ways to avoid the false-positive result in fNIRS studies. We employed spatial working memory (WM) and control tasks (e.g., resting state) to illustrate these points. Our results showed: (1) correlation between signals from prefrontal fNIRS and peripheral PPG is region-dependent. The high correlation with peripheral ear signal (i.e.,



    O


    2


    Hb

    ) occurred mainly in frontopolar regions in both spatial WM and control tasks. This may indicate the finding of task-dependent effect even in peripheral signals. We also found that the PPG recording at the ear has a high correlation with prefrontal fNIRS signal than the finger signals. (2) The systemic noise was reduced by 25% to 34% on average across regions, with a maximum of 39% to 58% in the highly correlated frontopolar region, by using these peripheral LFOs as noise regressors. (3) By performing the control tasks, we confirmed that the statistically significant activation was observed in the spatial WM task, not in the controls. This suggested that systemic (and any other) noises unlikely violated the major statistical inference. (4) Lastly, by denoising using the task-related signals, the significant activation of region-of-interest was still observed suggesting the manifest task-evoked response in the spatial WM task.
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