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Shang Y, Fan L, Feng J, Lv S, Wu M, Li B, Zang YS. Genotoxic and inflammatory effects of organic extracts from traffic-related particulate matter in human lung epithelial A549 cells: The role of quinones. Toxicol In Vitro 2013; 27:922-31. [DOI: 10.1016/j.tiv.2013.01.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 12/05/2012] [Accepted: 01/04/2013] [Indexed: 12/22/2022]
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277
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He L, Lin Y, Shang Y, Shelton BJ, Yu G. Using optical fibers with different modes to improve the signal-to-noise ratio of diffuse correlation spectroscopy flow-oximeter measurements. JOURNAL OF BIOMEDICAL OPTICS 2013; 18:037001. [PMID: 23455963 PMCID: PMC4023649 DOI: 10.1117/1.jbo.18.3.037001] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The dual-wavelength diffuse correlation spectroscopy (DCS) flow-oximeter is an emerging technique enabling simultaneous measurements of blood flow and blood oxygenation changes in deep tissues. High signal-to-noise ratio (SNR) is crucial when applying DCS technologies in the study of human tissues where the detected signals are usually very weak. In this study, single-mode, few-mode, and multimode fibers are compared to explore the possibility of improving the SNR of DCS flow-oximeter measurements. Experiments on liquid phantom solutions and in vivo muscle tissues show only slight improvements in flow measurements when using the few-mode fiber compared with using the single-mode fiber. However, light intensities detected by the few-mode and multimode fibers are increased, leading to significant SNR improvements in detections of phantom optical property and tissue blood oxygenation. The outcomes from this study provide useful guidance for the selection of optical fibers to improve DCS flow-oximeter measurements.
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Tian P, Zhou W, Liu J, Shang Y, Farrow CL, Juhás P, Billinge SJL. SrRietveld: a program for automating Rietveld refinements for high-throughput powder diffraction studies. J Appl Crystallogr 2013. [DOI: 10.1107/s0021889812045967] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SrRietveldis a highly automated software toolkit for Rietveld refinement. Compared to traditional refinement programs, it is more efficient to use and easier to learn. It is designed for modern high-throughput diffractometers and is capable of processing large numbers of data sets with minimal effort. The software currently uses conventional Rietveld refinement engines, automatingGSASandFullProfrefinements. However, as well as automating and extending many tasks associated with these programs, it is designed in a flexible and extensible way so that in the future these engines can be replaced with new refinement engines as they become available.SrRietveldis an open-source software package developed in Python.
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279
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Wen G, Shang Y, Guo J, Chen C, Shao H, Luo Q, Yang J, Wang H, Cheng G. Complete genome sequence and molecular characterization of thermostable Newcastle disease virus strain TS09-C. Virus Genes 2013; 46:542-5. [PMID: 23296874 DOI: 10.1007/s11262-012-0871-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 12/19/2012] [Indexed: 11/28/2022]
Abstract
A thermostable avirulent Newcastle disease virus (NDV) strain TS09-C was developed by serial passage of V4 strain in BHK-21 cells. The complete genome sequence of strain TS09-C was determined and compared with the sequences of other NDV isolates representing different thermostable phenotypes. The TS09-C genome was 15,186 nucleotides long and consisted of eight genes in the order of 3'-NP-P/V/W-M-F-HN-L-5'. High levels of nucleotide and amino acid sequence identity existed among the thermostable NDV isolates. Thermostable strains TS09-C, V4, I-2, and Ulster all belonged to genotype I. The F protein cleavage site of strain TS09-C was (112)G-K-Q-R-R-L(117), with an isolated basic amino acid and a pair of contiguous basic amino acids, differing from that of its parental V4 strain ((112)G-K-Q-G-R-L(117)). Our characterization of the complete genome of thermostable avirulent NDV strain TS09-C may facilitate the development of a thermostable NDV reverse genetic system and further study of the mechanism of thermostability of NDV.
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Shang Y, Gurley K, Yu G. Diffuse Correlation Spectroscopy (DCS) for Assessment of Tissue Blood Flow in Skeletal Muscle: Recent Progress. ACTA ACUST UNITED AC 2013; 3:128. [PMID: 24724043 PMCID: PMC3979478 DOI: 10.4172/2161-0940.1000128] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Near-infrared diffuse correlation spectroscopy (DCS) is an emerging technology for monitoring blood flow in various tissues. This article reviews the recent progress of DCS for the assessment of skeletal muscle blood flow, including the developments in technology allowing use during dynamic exercise and muscular electrical stimulation, the utilization for diagnosis of muscle vascular diseases, and the applications for evaluating treatment effects. The limitations of current DCS studies and future perspective are finally discussed.
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281
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Dong L, He L, Lin Y, Shang Y, Yu G. Simultaneously extracting multiple parameters via fitting one single autocorrelation function curve in diffuse correlation spectroscopy. IEEE Trans Biomed Eng 2012. [PMID: 23193446 DOI: 10.1109/tbme.2012.2226885] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Near-infrared diffuse correlation spectroscopy (DCS) has recently been employed for noninvasive acquisition of blood flow information in deep tissues. Based on the established correlation diffusion equation, the light intensity autocorrelation function detected by DCS is determined by a blood flow index αD(B), tissue absorption coefficient μ(a), reduced scattering coefficient μ'(s), and a coherence factor β. This study is designed to investigate the possibility of extracting multiple parameters such as μ(a), μ'(s), β, and αD(B) through fitting one single autocorrelation function curve and evaluate the performance of different fitting methods. For this purpose, computer simulations, tissue-like phantom experiments, and in vivo tissue measurements were utilized. The results suggest that it is impractical to simultaneously fit αD(B) and μ(a) or αD(B) and μ'(s) from one single autocorrelation function curve due to the large crosstalk between these paired parameters. However, simultaneously fitting β and αD(B) is feasible and generates more accurate estimation with smaller standard deviation compared to the conventional two-step fitting method (i.e., first calculating β and then fitting αD(B)). The outcomes from this study provide a crucial guidance for DCS data analysis.
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Shang Y, Gurley K, Symons B, Long D, Srikuea R, Crofford LJ, Peterson CA, Yu G. Noninvasive optical characterization of muscle blood flow, oxygenation, and metabolism in women with fibromyalgia. Arthritis Res Ther 2012; 14:R236. [PMID: 23116302 PMCID: PMC3674608 DOI: 10.1186/ar4079] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 10/25/2012] [Indexed: 12/11/2022] Open
Abstract
Introduction Women with fibromyalgia (FM) have symptoms of increased muscular fatigue and reduced exercise tolerance, which may be associated with alterations in muscle microcirculation and oxygen metabolism. This study used near-infrared diffuse optical spectroscopies to noninvasively evaluate muscle blood flow, blood oxygenation and oxygen metabolism during leg fatiguing exercise and during arm arterial cuff occlusion in post-menopausal women with and without FM. Methods Fourteen women with FM and twenty-three well-matched healthy controls participated in this study. For the fatiguing exercise protocol, the subject was instructed to perform 6 sets of 12 isometric contractions of knee extensor muscles with intensity steadily increasing from 20 to 70% maximal voluntary isometric contraction (MVIC). For the cuff occlusion protocol, forearm arterial blood flow was occluded via a tourniquet on the upper arm for 3 minutes. Leg or arm muscle hemodynamics, including relative blood flow (rBF), oxy- and deoxy-hemoglobin concentration ([HbO2] and [Hb]), total hemoglobin concentration (THC) and blood oxygen saturation (StO2), were continuously monitored throughout protocols using a custom-built hybrid diffuse optical instrument that combined a commercial near-infrared oximeter for tissue oxygenation measurements and a custom-designed diffuse correlation spectroscopy (DCS) flowmeter for tissue blood flow measurements. Relative oxygen extraction fraction (rOEF) and oxygen consumption rate (rVO2) were calculated from the measured blood flow and oxygenation data. Post-manipulation (fatiguing exercise or cuff occlusion) recovery in muscle hemodynamics was characterized by the recovery half-time, a time interval from the end of manipulation to the time that tissue hemodynamics reached a half-maximal value. Results Subjects with FM had similar hemodynamic and metabolic response/recovery patterns as healthy controls during exercise and during arterial occlusion. However, tissue rOEF during exercise in subjects with FM was significantly lower than in healthy controls, and the half-times of oxygenation recovery (Δ[HbO2] and Δ[Hb]) were significantly longer following fatiguing exercise and cuff occlusion. Conclusions Our results suggest an alteration of muscle oxygen utilization in the FM population. This study demonstrates the potential of using combined diffuse optical spectroscopies (i.e., NIRS/DCS) to comprehensively evaluate tissue oxygen and flow kinetics in skeletal muscle.
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Cheng R, Shang Y, Hayes D, Saha SP, Yu G. Noninvasive optical evaluation of spontaneous low frequency oscillations in cerebral hemodynamics. Neuroimage 2012; 62:1445-54. [DOI: 10.1016/j.neuroimage.2012.05.069] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Revised: 05/11/2012] [Accepted: 05/24/2012] [Indexed: 01/15/2023] Open
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284
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Xuan C, Wang Q, Han X, Duan Y, Li L, Shi L, Wang Y, Shan L, Yao Z, Shang Y. RBB, a novel transcription repressor, represses the transcription of HDM2 oncogene. Oncogene 2012; 32:3711-21. [PMID: 22926524 DOI: 10.1038/onc.2012.386] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2012] [Revised: 07/11/2012] [Accepted: 07/13/2012] [Indexed: 01/04/2023]
Abstract
The p53 tumor suppressor is important in many aspects of cell biology. Tight regulation of p53 is thus imperative for maintaining cell homeostasis and preventing tumorigenesis. The stabilization and activity of p53 is primarily regulated by MDM2, which is encoded for by HDM2. However, how the expression and activity of MDM2 is regulated remains largely unknown. Here, we report a novel BTB and BEN domains-containing protein, RBB. We demonstrated that RBB is a novel transcriptional repressor binding specific DNA motif via a homodimer and interacting with the nucleosome remodeling and deacetylase (NuRD) complex. Genome wide transcription target analysis by ChIP sequencing revealed that RBB represses the transcription of a series of functionally important genes including HDM2. We showed that RBB recruits the NuRD complex to the internal promoter of HDM2 and inhibits the expression of MDM2 protein, leading to subsequent stabilization of tumor suppressor p53. Significantly, we showed that RBB suppresses cell proliferation and sensitizes cells to DNA damage-induced apoptosis. Our data indicate that RBB is a novel transcriptional repressor and an important regulator of p53 pathway.
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285
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Amasaki Y, Hirano S, Shang Y, Sawai T, Nishimura M, Shimada Y, Kakinuma S. 726 Molecular Interaction of X-rays and N-ethyl-N-nitrosourea in Thymic Lymphomagenesis Depends on the Interval of Two Treatments. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71367-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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286
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Gurley K, Shang Y, Yu G. Noninvasive optical quantification of absolute blood flow, blood oxygenation, and oxygen consumption rate in exercising skeletal muscle. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:075010. [PMID: 22894482 PMCID: PMC3395077 DOI: 10.1117/1.jbo.17.7.075010] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Revised: 06/11/2012] [Accepted: 06/13/2012] [Indexed: 05/19/2023]
Abstract
This study investigates a method using novel hybrid diffuse optical spectroscopies [near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS)] to obtain continuous, noninvasive measurement of absolute blood flow (BF), blood oxygenation, and oxygen consumption rate (V̇O(2)) in exercising skeletal muscle. Healthy subjects (n=9) performed a handgrip exercise to increase BF and V̇O(2) in forearm flexor muscles, while a hybrid optical probe on the skin surface directly monitored oxy-, deoxy-, and total hemoglobin concentrations ([HbO(2)], [Hb], and THC), tissue oxygen saturation (S(t)O(2)), relative BF (rBF), and relative oxygen consumption rate (rV̇O(2)). The rBF and rV̇O(2) signals were calibrated with absolute baseline BF and V̇O(2) obtained through venous and arterial occlusions, respectively. Known problems with muscle-fiber motion artifacts in optical measurements during exercise were mitigated using a novel gating algorithm that determined muscle contraction status based on control signals from a dynamometer. Results were consistent with previous findings in the literature. This study supports the application of NIRS/DCS technology to quantitatively evaluate hemodynamic and metabolic parameters in exercising skeletal muscle and holds promise for improving diagnosis and treatment evaluation for patients suffering from diseases affecting skeletal muscle and advancing fundamental understanding of muscle and exercise physiology.
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287
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Shang Y, Chen C, Li Y, Zhao J, Zhu T. Hydroxyl radical generation mechanism during the redox cycling process of 1,4-naphthoquinone. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:2935-2942. [PMID: 22288565 DOI: 10.1021/es203032v] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Airborne quinones contribute to adverse health effects of ambient particles probably because of their ability to generate hydroxyl radicals (·OH) via redox cycling, but the mechanisms remain unclear. We examined the chemical mechanisms through which 1,4-naphthoquinone (1,4-NQ) induced ·OH, and the redox interactions between 1,4-NQ and ascorbate acid (AscH(2)). First, ·OH formation by 1,4-NQ was observed in cellular and acellular systems, and was enhanced by AscH(2). AscH(2) also exacerbated the cytotoxicity of 1,4-NQ in Ana-1 macrophages, at least partially due to enhanced ·OH generation. The detailed mechanism was studied in an AscH(2)/H(2)O(2) physiological system. The existence of a cyclic 1,4-NQ process was shown by detecting the corresponding semiquinone radical (NSQ·-) and hydroquinone (NQH(2)). 1,4-NQ was reduced primarily to NSQ·- by O2·- (which was from AscH(2) reacting with H(2)O(2)), not by AscH(2) as normally thought. At lower doses, 1,4-NQ consumed O2·- to suppress ·OH; however, at higher doses, 1,4-NQ presented a positive association with ·OH. The reaction of NSQ·- with H(2)O(2) to release ·OH was another important channel for OH radical formation except for Haber-Weiss reaction. As a reaction precursor for O2·-, the enhanced ·OH response to 1,4-NQ by AscH(2) was indirect. Reducing substrates were necessary to sustain the redox cycling of 1,4-NQ, leading to more ·OH and a deleterious end point.
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288
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Wei B, Zhang H, Li L, Li M, Shang Y. T helper 17 cells and regulatory T-cell imbalance in paediatric patients with asthma. J Int Med Res 2012; 39:1293-305. [PMID: 21986131 DOI: 10.1177/147323001103900417] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Asthma is a chronic inflammatory disorder of the lung, which is thought to be determined by the balance between the T helper (Th)2 and Th1 responses. This study evaluated whether the balance between Th17 cells and regulatory T cells (T(reg)) was impaired in asthma patients. The proportion of peripheral blood Th17 cells of the total CD4(+) cell population in asthma patients was significantly higher than in controls (mean ± SD 0.72 ± 0.5% versus 0.31 ± 0.4%, respectively). The proportion of peripheral T(reg) cells in asthma patients was significantly lower than in controls (mean ± SD 12.1 ± 4.6% versus 27.2 ± 7.5%, respectively). Analysis of mRNA generally confirmed the flow cytometry data, suggesting that the changes in cytokine levels were mediated at the transcription level. In paediatric asthma patients, the CD4(+) T-cell phenotype was skewed toward the Th17 phenotype, suggesting that a Th17/T(reg) functional imbalance plays a role in asthma.
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Huang XL, Dai LZ, Lu P, Shang Y, Li Y, Tao YB, Huang W. [Time-series analysis on the acute mortality affected by air pollution, in the city of Guangzhou, 2004-2008]. ZHONGHUA LIU XING BING XUE ZA ZHI = ZHONGHUA LIUXINGBINGXUE ZAZHI 2012; 33:210-214. [PMID: 22575146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
OBJECTIVE To study the associations between daily mortality and the status of exposure to air pollution. METHODS A time-series analysis was conducted to assess the relations between acute mortality and exposure to respiratory particulate matter (PM(10)), sulfur-dioxide (SO2) and nitrogen dioxide (NO2) in urban residents of Guangzhou (2004 - 2008), using Poisson regression. RESULTS Through controlling the factors as temperature, relative humidity, age, gender and time, significant increases were observed in all-cause mortality of 0.94% (0.79 - 1.09) for PM(10), 1.55% (1.31 - 1.78) for NO2, and 1.09% (0.91 - 1.27) for SO2, per 10 µg/m(3), when increase of the lagging 2-day average concentrations of air pollution was seen, in Guangzhou. Stronger effects of exposure to air pollution were found on cardiovascular and respiratory mortality, as well as in elderly (≥ 65 years) and female population. CONCLUSION Our results suggested that exposure to ambient pollution was significantly associated with the increase of excess risks, on total and cardio-respiratory mortality in the residents of Guangzhou.
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Dong L, Kudrimoti M, Cheng R, Shang Y, Johnson EL, Stevens SD, Shelton BJ, Yu G. Noninvasive diffuse optical monitoring of head and neck tumor blood flow and oxygenation during radiation delivery. BIOMEDICAL OPTICS EXPRESS 2012; 3:259-72. [PMID: 22312579 PMCID: PMC3269843 DOI: 10.1364/boe.3.000259] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Revised: 12/15/2011] [Accepted: 01/01/2012] [Indexed: 05/19/2023]
Abstract
This study explored using a novel diffuse correlation spectroscopy (DCS) flow-oximeter to noninvasively monitor blood flow and oxygenation changes in head and neck tumors during radiation delivery. A fiber-optic probe connected to the DCS flow-oximeter was placed on the surface of the radiologically/clinically involved cervical lymph node. The DCS flow-oximeter in the treatment room was remotely operated by a computer in the control room. From the early measurements, abnormal signals were observed when the optical device was placed in close proximity to the radiation beams. Through phantom tests, the artifacts were shown to be caused by scattered x rays and consequentially avoided by moving the optical device away from the x-ray beams. Eleven patients with head and neck tumors were continually measured once a week over a treatment period of seven weeks, although there were some missing data due to the patient related events. Large inter-patient variations in tumor hemodynamic responses were observed during radiation delivery. A significant increase in tumor blood flow was observed at the first week of treatment, which may be a physiologic response to hypoxia created by radiation oxygen consumption. Only small and insignificant changes were found in tumor blood oxygenation, suggesting that oxygen utilizations in tumors during the short period of fractional radiation deliveries were either minimal or balanced by other effects such as blood flow regulation. Further investigations in a large patient population are needed to correlate the individual hemodynamic responses with the clinical outcomes for determining the prognostic value of optical measurements.
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291
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Munk N, Symons B, Shang Y, Cheng R, Yu G. Noninvasively measuring the hemodynamic effects of massage on skeletal muscle: A novel hybrid near-infrared diffuse optical instrument. J Bodyw Mov Ther 2012; 16:22-8. [DOI: 10.1016/j.jbmt.2011.01.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2010] [Revised: 12/30/2010] [Accepted: 01/14/2011] [Indexed: 11/15/2022]
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292
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Lin Y, He L, Shang Y, Yu G. Noncontact diffuse correlation spectroscopy for noninvasive deep tissue blood flow measurement. JOURNAL OF BIOMEDICAL OPTICS 2012; 17:010502. [PMID: 22352631 PMCID: PMC4019367 DOI: 10.1117/1.jbo.17.1.010502] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 12/01/2011] [Accepted: 12/01/2011] [Indexed: 05/19/2023]
Abstract
A noncontact diffuse correlation spectroscopy (DCS) probe has been developed using two separated optical paths for the source and detector. This unique design avoids the interference between the source and detector and allows large source-detector separations for deep tissue blood flow measurements. The noncontact probe has been calibrated against a contact probe in a tissue-like phantom solution and human muscle tissues; flow changes concurrently measured by the two probes are highly correlated in both phantom (R(2)=0.89, p<10(-5)) and real-tissue (R(2)=0.77, p<10(-5), n=9) tests. The noncontact DCS holds promise for measuring blood flow in vulnerable (e.g., pressure ulcer) and soft (e.g., breast) tissues without distorting tissue hemodynamic properties.
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293
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Shang Y, Chen L, Toborek M, Yu G. Diffuse optical monitoring of repeated cerebral ischemia in mice. OPTICS EXPRESS 2011; 19:20301-15. [PMID: 21997041 PMCID: PMC3495871 DOI: 10.1364/oe.19.020301] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Revised: 09/09/2011] [Accepted: 09/09/2011] [Indexed: 05/18/2023]
Abstract
Occlusions of bilateral common carotid arteries (bi-CCA) in mice are popular models for the investigation of transient forebrain ischemia. Currently available technologies for assessing cerebral blood flow (CBF) and oxygenation in ischemic mice have limitations. This study tests a novel near-infrared diffuse correlation spectroscopy (DCS) flow-oximeter for monitoring both CBF and cerebral oxygenation in mice undergoing repeated transient forebrain ischemia. Concurrent flow measurements in a mouse brain were first conducted for validation purposes; DCS measurement was found highly correlated with laser Doppler measurement (R2 = 0.94) and less susceptible to motion artifacts. With unique designs in experimental protocols and fiber-optic probes, we have demonstrated high sensitivities of DCS flow-oximeter in detecting the regional heterogeneity of CBF responses in different hemispheres and global changes of both CBF and cerebral oxygenation across two hemispheres in mice undergoing repeated 2-minute bi-CCA occlusions over 5 days. More than 75% CBF reductions were found during bi-CCA occlusions in mice, which may be considered as a threshold to determine a successful bi-CCA occlusion. With the progress of repeated 2-minute bi-CCA occlusions over days, a longitudinal decline in the magnitudes of CBF reduction was observed, indicating the brain adaptation to cerebral ischemia through the repeated preconditioning.
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Juhas P, Farrow CL, Liu J, Zhou W, Tian P, Shang Y, Billinge SJL. DiffPy– an open-source library for powder crystallography. Acta Crystallogr A 2011. [DOI: 10.1107/s0108767311096498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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295
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Shang Y, Gu PF, Shang Y, Li Y. [Penehyclidine hydrochloride inhibits glutamate release and related research in global brain ischemia/reperfusion rats]. ZHONGGUO YING YONG SHENG LI XUE ZA ZHI = ZHONGGUO YINGYONG SHENGLIXUE ZAZHI = CHINESE JOURNAL OF APPLIED PHYSIOLOGY 2011; 27:353-356. [PMID: 22097734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
OBJECTIVE To investigate the effect of penehyclidine hydrochloride on glutamate (Glu)release and N-methyl-D-aspartate receptor (NMDAR)1 expression in hippocampus CA1 with global cerebral ischemia/reperfusion rats. METHODS Sixty male Wistar rats were randomly allocated into three groups; group A received sham operation; group B received ischemia/reperfusion; group C received penehyclidine hydrochloride treatment (2 mg/kg) before ischemia/reperfusion (n=20). Global cerebral ischemia was induced according to Pulsinelli-Brierley method. All animals were divided into two experiments: (I) Microdialysis plus HPLC/FD were used to detect Glu level after reperfusion 1 h, 3 h, 6 h. (II) After reperfusion 3 h, the animals were decapitated on ice and the brains were immediately removed to detect NMDAR1 expression in CA1 area by immunohistochemistry. RESULTS After penehyclidine hydrochloride treatment, extracellular Glu level in CA1 were significantly decreased compared with those of control group (P < 0.05 or 0.01); Total integrated OD, average gray value and positive-cell area of NMDAR1 in CA1 were also significantly decreased compared with those of control group (P < 0.05 or 0.01). CONCLUSION Penehyclidine hydrochloride might has protective effect in hippocampus CA1 on global cerebral ischemia/reperfusion animals. The protective mechanism might be involved in inhibiting Glu release and NMDAR1 expression.
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Irwin D, Dong L, Shang Y, Cheng R, Kudrimoti M, Stevens SD, Yu G. Influences of tissue absorption and scattering on diffuse correlation spectroscopy blood flow measurements. BIOMEDICAL OPTICS EXPRESS 2011; 2:1969-85. [PMID: 21750773 PMCID: PMC3130582 DOI: 10.1364/boe.2.001969] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2011] [Revised: 06/13/2011] [Accepted: 06/14/2011] [Indexed: 05/19/2023]
Abstract
In this study we evaluate the influences of optical property assumptions on near-infrared diffuse correlation spectroscopy (DCS) flow index measurements. The optical properties, absorption coefficient (µ(a)) and reduced scattering coefficient (µ(s)'), are independently varied using liquid phantoms and measured concurrently with the flow index using a hybrid optical system combining a dual-wavelength DCS flow device with a commercial frequency-domain tissue-oximeter. DCS flow indices are calculated at two wavelengths (785 and 830 nm) using measured µ(a) and µ(s)' or assumed constant µ(a) and µ(s)'. Inaccurate µ(s)' assumptions resulted in much greater flow index errors than inaccurate µ(a). Underestimated/overestimated µ(s)' from -35%/+175% lead to flow index errors of +110%/-80%, whereas underestimated/overestimated µ(a) from -40%/+150% lead to -20%/+40%, regardless of the wavelengths used. Examination of a clinical study involving human head and neck tumors indicates up to +280% flow index errors resulted from inter-patient optical property variations. These findings suggest that studies involving significant µ(a) and µ(s)' changes should concurrently measure flow index and optical properties for accurate extraction of blood flow information.
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Qian J, Yao K, Xue L, Xie G, Zheng Y, Wang C, Shang Y, Wang H, Wan L, Liu L, Li C, Ji W, Wang Y, Xu P, Yu S, Tang YW, Yang Y. Diversity of pneumococcal surface protein A (PspA) and relation to sequence typing in Streptococcus pneumoniae causing invasive disease in Chinese children. Eur J Clin Microbiol Infect Dis 2011; 31:217-23. [DOI: 10.1007/s10096-011-1296-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Accepted: 05/11/2011] [Indexed: 10/18/2022]
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298
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Symons TB, Munk N, Shang Y, Cheng R, Yu G. Lower Limb Massage Increases Skeletal Muscle Blood Flow in Young Women. Med Sci Sports Exerc 2011. [DOI: 10.1249/01.mss.0000400811.19193.54] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Shang Y, Cheng R, Dong L, Ryan SJ, Saha SP, Yu G. Cerebral monitoring during carotid endarterectomy using near-infrared diffuse optical spectroscopies and electroencephalogram. Phys Med Biol 2011; 56:3015-32. [PMID: 21508444 DOI: 10.1088/0031-9155/56/10/008] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Intraoperative monitoring of cerebral hemodynamics during carotid endarterectomy (CEA) provides essential information for detecting cerebral hypoperfusion induced by temporary internal carotid artery (ICA) clamping and post-CEA hyperperfusion syndrome. This study tests the feasibility and sensitivity of a novel dual-wavelength near-infrared diffuse correlation spectroscopy technique in detecting cerebral blood flow (CBF) and cerebral oxygenation in patients undergoing CEA. Two fiber-optic probes were taped on both sides of the forehead for cerebral hemodynamic measurements, and the instantaneous decreases in CBF and electroencephalogram (EEG) alpha-band power during ICA clamping were compared to test the measurement sensitivities of the two techniques. The ICA clamps resulted in significant CBF decreases (-24.7 ± 7.3%) accompanied with cerebral deoxygenation at the surgical sides (n = 12). The post-CEA CBF were significantly higher (+43.2 ± 16.9%) than the pre-CEA CBF. The CBF responses to ICA clamping were significantly faster, larger and more sensitive than EEG responses. Simultaneous monitoring of CBF, cerebral oxygenation and EEG power provides a comprehensive evaluation of cerebral physiological status, thus showing potential for the adoption of acute interventions (e.g., shunting, medications) during CEA to reduce the risks of severe cerebral ischemia and cerebral hyperperfusion syndrome.
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300
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Peng B, Mao Y, Tang XF, Shang Y, Shen CY, Guo Y, Xiang Y, Yang ZW. Comparison of spermatogenic damage induced at 6 months after ligation of the vas deferens at proximal and distal locations in the rabbit. Andrologia 2011; 43:129-38. [PMID: 21382067 DOI: 10.1111/j.1439-0272.2009.01034.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Recent study in rabbits demonstrated that vasectomy via the inguinal canal did not result in any spermatogenic damage 3 months postoperation; this study aimed to determine whether the damage would occur in a longer term. The left or right vas deferens was ligated near the epididymal head (unilateral proximal vasectomy, 12 animals) or via the inguinal canal (unilateral distal vasectomy, 11 animals) in adult male rabbits, with a sham operation being performed on the contralateral side. Six months postoperation, testes, epididymides and vasa deferentia were removed and methacrylate resin-embedded sections prepared to evaluate spermatogenesis by histological (qualitative) and stereological (quantitative) studies. The juxta-epididymal segment of the occluded vas deferens was severely distended (filled with sperm) in 10 of the 11 animals with distal vasectomy and moderately or slightly distended in nine of the 12 animals with proximal vasectomy. Severe spermatogenic damage occurred in seven animals with proximal vasectomy (the juxta-epididymal vas moderately or slightly distended), in only one animal with distal vasectomy (the vas not severely distended). In conclusion, spermatogenic damage occurred at 6 months postvasectomy in some animals, especially those with proximal vasectomy and therefore shorter occluded reproductive tract for sperm storage; the damage was probably intra-tract pressure mediated.
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