Publications by authors named "Zhun Xu"

20 Publications

  • Page 1 of 1

Percutaneous spinal endoscopy with unilateral interlaminar approach to perform bilateral decompression for central lumbar spinal stenosis: radiographic and clinical assessment.

BMC Musculoskelet Disord 2021 Mar 1;22(1):236. Epub 2021 Mar 1.

Department of Spine Surgery, The First Affiliated Hospital of University of South China, Hengyang, People's Republic of China.

Background: Recently, a percutaneous spinal endoscopy unilateral posterior interlaminar approach to perform bilateral decompression has been proposed for use in treatment of lumbar spinal stenosis, As a development and supplement to traditional surgery, its advantages regarding therapeutic effects and prognosis, such as minor soft tissue damage, little intraoperative blood loss, and a quick return to daily life. However, there are few analyses of this surgery with a follow-up of more than 1 year,we conducted this study in order to quantitatively investigate radiographic and clinical efficacies of this surgery for central lumbar spinal stenosis.

Materials And Methods: Forty-six patients with central lumbar spinal stenosis were enrolled from January 2017 to July 2018. The visual analog scale (VAS) for back pain and leg pain, Oswestry disability index (ODI), modified MacNab criteria were used to evaluate clinical efficiency at preoperative and postoperative time points. The intervertebral height index (IHI), cross-sectional area of the spinal canal (CSAC), calibrated disc signal (CDS) and spinal stability were examined to assess radiographic decompression efficiency via magnetic resonance imaging and X-ray at preoperative and postoperative time points.

Results: The VAS score for lower back pain and leg pain improved from 7.50 ± 0.78 to 1.70 ± 0.66 and from 7.30 ± 0.79 to 1.74 ± 0.68, respectively, and the ODI improved from 72.35 ± 8.15 to 16.15 ± 4.51. In terms of modified MacNab criteria, 91.3% of the patients achieved good or excellent outcomes. Furthermore, significant changes after surgery were observed for the percentage of CSAC, increasing from 125.3 ± 53.9 to 201.4 ± 78 mm; however, no significant differences were observed for the remaining measurement indicators.

Conclusions: The clinical and radiographic efficacies of this surgery for central lumbar spinal stenosis were good in short-term follow-up, and this surgery did not cause meaningful changes in IHI, CDS, and spine stability in short-term follow-up. The effect of long-term follow-up needs further investigation.
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http://dx.doi.org/10.1186/s12891-021-04100-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7923329PMC
March 2021

(Hydrostachyaceae), a new species from Madagascar.

PhytoKeys 2020 20;167:45-56. Epub 2020 Nov 20.

Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.

, a new species of Hydrostachyaceae found in a stream in Manandriana, Madagascar, is described and illustrated herein. It is similar to and in morphology, but can be distinguished from them by its leaves with sparsely arranged, flabelliform and palmately parted emergences, obvious rachis and the pattern of segments arranged on the male bracts. Molecular phylogenetic analysis of the nuclear ribosomal internal transcribed spacer (ITS) dataset provides a robust support for it as a new species as well.
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http://dx.doi.org/10.3897/phytokeys.167.58538DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7695676PMC
November 2020

A finite element analysis of sacroiliac joint displacements and ligament strains in response to three manipulations.

BMC Musculoskelet Disord 2020 Oct 28;21(1):709. Epub 2020 Oct 28.

School of Traditional Chinese Medicine, Southern Medical University, No. 1838, Guangzhou Avenue North, BaiYun District, Guangzhou, 510515, Guangdong Province, China.

Background: Clinical studies have found that manipulations have a good clinical effect on sacroiliac joint (SIJ) pain without specific causes. However, the specific mechanisms underlying the effect of manipulations are still unclear. The purpose of this study was to investigate the effects of three common manipulations on the stresses and displacements of the normal SIJ and the strains of the surrounding ligaments.

Methods: A three-dimensional finite element model of the pelvis-femur was developed. The manipulations of hip and knee flexion (MHKF), oblique pulling (MOP), and lower limb hyperextension (MLLH) were simulated. The stresses and displacements of the SIJ and the strains of the surrounding ligaments were analyzed during the three manipulations.

Results: MOP produced the highest stress on the left SIJ, at 6.6 MPa, while MHKF produced the lowest stress on the right SIJ, at 1.5 MPa. The displacements of the SIJ were all less than 1 mm during the three manipulations. The three manipulations caused different degrees of ligament strain around the SIJ, and MOP produced the greatest straining of the ligaments.

Conclusion: The three manipulations all produced small displacements of the SIJ and different degrees of ligament strains, which might be the mechanism through which they relieve SIJ pain. MOP produced the largest displacement and the greatest ligament strains.
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http://dx.doi.org/10.1186/s12891-020-03735-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7594473PMC
October 2020

lncRNA SNHG1 attenuates osteogenic differentiation via the miR‑101/DKK1 axis in bone marrow mesenchymal stem cells.

Mol Med Rep 2020 Nov 2;22(5):3715-3722. Epub 2020 Sep 2.

Department of Orthopedics and Traumatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong 510515, P.R. China.

The imbalance induced by inhibition of bone mesenchymal stem cell (BMSC) osteogenic differentiation results in osteoporosis (OP); however, the underlying regulatory mechanism is not completely understood. Long non‑coding RNAs (lncRNAs) serve crucial roles in osteogenic differentiation; therefore, investigating their regulatory role in the process of osteogenic differentiation may identify a promising therapeutic target for OP. The expression of small nucleolar RNA host gene 1 (SNHG1), Dickkopf 1 (DKK1), microRNA (miR)‑101, RUNX family transcription factor 2 (RUNX2), osteopontin (OPN) and osteocalin (OCN) were detected via reverse transcription‑quantitative PCR. The protein expression levels of DKK1, β‑catenin, RUNX2, OPN, OCN, osterix and collagen type I α1 chain were analyzed by performing western blotting. The osteoblastic phenotype was assessed by conducting alkaline phosphatase activity detection and Alizarin Red staining. The interaction between SNHG1 and miR‑101 was validated by bioinformatics and luciferase assays. The regulatory role of SNHG1 in BMSC osteogenic differentiation was assessed. SNHG1 expression was downregulated in a time‑dependent manner during the process of osteogenic differentiation. SNHG1 overexpression inhibited osteogenic differentiation compared with the pcDNA group. The results indicated that SNHG1 and DKK1 directly interacted with miR‑101. Moreover, SNHG1 regulated the Wnt/β‑catenin signaling pathway to inhibit osteogenic differentiation via the miR‑101/DKK1 axis. The present study indicated that lncRNA SNHG1 could attenuate BMSC osteogenic differentiation via the miR‑101/DKK1 axis as a competitive endogenous RNA. Therefore, the present study furthered the current understanding of the potential mechanism underlying lncRNAs in in osteogenic differentiation.
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http://dx.doi.org/10.3892/mmr.2020.11489DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7533455PMC
November 2020

Exacerbations, Health Resource Utilization, and Costs Among Medicare Beneficiaries with Chronic Obstructive Pulmonary Disease Treated with Nebulized Arformoterol Following a Respiratory Event.

Chronic Obstr Pulm Dis 2019 Oct;6(4)

Department of Family Medicine and Public Health, Division of Health Policy, University of California San Diego, La Jolla.

Background: Long-acting beta2-agonists (LABAs), with or without inhaled corticosteroids (ICSs), delivered by handheld inhalers or nebulizers are recommended as maintenance therapy in chronic obstructive pulmonary disease (COPD). This study evaluated exacerbations, health resource utilization (HRU), and costs among Medicare beneficiaries with COPD on handheld ICS+LABA who switched to nebulized arformoterol (ARF) or continued ICS+LABA following a respiratory event.

Methods: Using Medicare claims, we identified beneficiaries with COPD (international classification of disease, 9th revision, clinical modification [ICD-9-CM] 490-492.xx, 494.xx, 496.xx) between 2010-2014 who had ≥ 1 year of continuous enrollment in Parts A, B, and D; ≥ 2 COPD-related outpatient visits ≥ 30 days apart or ≥ 1 hospitalization(s); ICS+LABA use 90-days before ARF initiation; and a respiratory event (COPD-related hospitalization or emergency department [ED] visit < 30 days before ARF initiation). Using propensity scores, 423 beneficiaries who switched to ARF were matched to 423 beneficiaries who continued on handheld ICS+LABA (controls). Difference-in-difference regression models examined outcomes at 180-days follow-up.

Results: Beneficiaries who switched to ARF had 1.5 fewer exacerbations (=0.015) but no difference in hospitalizations and ED visits compared to controls. Durable medical equipment (DME) costs were higher among ARF users than controls ($1590), yet total health care costs were similar due to cost offsets by ARF in pharmacy (-$794), inpatient (-$524), and outpatient care (-$65). ARF accounted for 55% ($886.63) of DME costs, with the remaining costs attributed to oxygen therapy ($428.10) and nebulized corticosteroids ($590.85).

Conclusions: Switching from handheld ICS+LABA to nebulized ARF resulted in fewer COPD exacerbations among Medicare beneficiaries. Nebulized LABAs may improve outcomes in selected patients with COPD.
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http://dx.doi.org/10.15326/jcopdf.6.4.2019.0127DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7006702PMC
October 2019

Predictors of Nebulized Arformoterol Treatment: A Retrospective Analysis of Medicare Beneficiaries with Chronic Obstructive Pulmonary Disease.

COPD 2019 04 19;16(2):140-151. Epub 2019 Jun 19.

d Advance Health Solutions, LLC , New York , NY , USA.

This study examined sociodemographic and clinical characteristics, treatment patterns, and health resource utilization among Medicare beneficiaries with chronic obstructive pulmonary disease (COPD) to identify predictors of nebulized arformoterol treatment. Using Medicare administrative data from 2010 to 2014, beneficiaries with ≥2 COPD outpatient visits ≥30 d apart or ≥1 COPD-related hospitalization(s) (ICD-9-CM 491.xx, 492.xx, and 496) were identified. Inclusion criteria required ≥1 COPD medication claim(s) and continuous enrollment in Parts A, B, and D. Four cohorts were identified: (a) 11,887 arformoterol users, (b) a subsample of arformoterol users ( 1,778) who were hospitalized and discharged 30 d before initiating arformoterol, (c) 450,178 controls who had not received arformoterol, and (d) a subsample of controls ( 21,910) who had hospitalizations. Logistic regression analysis was used to evaluate predictors of arformoterol treatment. The majority of beneficiaries were older than 70 years of age, female, Caucasian, and 47% were dual-eligible. The strongest predictors of arformoterol treatment were oxygen therapy, systemic corticosteroid or methylxanthine use, an exacerbation, a COPD-related hospitalization, and receiving care from a pulmonologist (all  < .001). Dual-eligibility, being a racial/ethnic minority, and having severe psychiatric comorbidity or immunodeficiency lowered the odds of receiving nebulized arformoterol (all  < .001). Among beneficiaries with recent hospitalizations, exacerbations and COPD-related admissions increased the odds of receiving arformoterol ( < .001). Nebulized arformoterol treatment was more likely to be initiated in sicker patients with COPD. Ensuring access to nebulized maintenance therapy is important and particularly warranted for COPD populations with greater medical needs.
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http://dx.doi.org/10.1080/15412555.2019.1618256DOI Listing
April 2019

Medication management patterns among Medicare beneficiaries with chronic obstructive pulmonary disease who initiate nebulized arformoterol treatment.

Int J Chron Obstruct Pulmon Dis 2019 15;14:1019-1031. Epub 2019 May 15.

Department of Family Medicine and Public Health, University of California San Diego, La Jolla, CA, USA.

Global evidence-based treatment strategies for chronic obstructive pulmonary disease (COPD) recommend using long-acting bronchodilators (LABDs) as maintenance therapy. However, COPD patients are often undertreated. We examined COPD treatment patterns among Medicare beneficiaries who initiated arformoterol tartrate, a nebulized long-acting beta agonist (LABA), and identified the predictors of initiation. Using a 100% sample of Medicare administrative data, we identified beneficiaries with a COPD diagnosis (ICD-9 490-492.xx, 494.xx, 496.xx) between 2010 and 2014 who had ≥1 year of continuous enrollment in Parts A, B, and D, and ≥2 COPD-related outpatient visits within 30 days or ≥1 hospitalization(s). After applying inclusion/exclusion criteria, three cohorts were identified: (1) study group beneficiaries who received nebulized arformoterol (n=11,886), (2) a subset of the study group with no LABD use 90 days prior to initiating arformoterol (n=5,542), and (3) control group beneficiaries with no nebulized LABA use (n=220,429). Logistic regression was used to evaluate predictors of arformoterol initiation. Odds ratios (ORs), 95% confidence intervals (CIs), and values were computed. Among arformoterol users, 47% (n=5,542) had received no LABDs 90 days prior to initiating arformoterol. These beneficiaries were being treated with a nebulized (50%) or inhaled (37%) short-acting bronchodilator or a systemic corticosteroid (46%), and many received antibiotics (37%). Compared to controls, beneficiaries who initiated arformoterol were significantly more likely to have had an exacerbation, a COPD-related hospitalization, and a pulmonologist or respiratory therapist visit prior to initiation (all <0.05). Beneficiaries with moderate/severe psychiatric comorbidity or dual-eligible status were significantly less likely to initiate arformoterol, as compared to controls (all <0.05). Medicare beneficiaries who initiated nebulized arformoterol therapy had more exacerbations and hospitalizations than controls 90 days prior to initiation. Findings revealed inadequate use of maintenance medications, suggesting a lack of compliance with evidence-based treatment guidelines.
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http://dx.doi.org/10.2147/COPD.S199251DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6526678PMC
January 2020

The Changing Pattern of Nutrition Intake by Social Class in Contemporary China, 1991-2011.

Authors:
Zhun Xu Wei Zhang

Am J Public Health 2017 11 21;107(11):1809-1811. Epub 2017 Sep 21.

Zhun Xu is with the Department of Economics, Howard University, Washington, DC. Wei Zhang is with the School of Marxism, Tsinghua University, Beijing, China.

Objectives: To explore the changing pattern of nutrition intake by social class in contemporary China.

Methods: We defined social class in 2 ways. The first definition was based on employment, and the second definition was based on per capita household income levels. We used China Health and Nutrition Survey data from 1991 to 2011 to show the changes in the relation between social class and nutrition intake.

Results: The relation between social class and nutrition intake in China changed significantly within the 2 decades. For example, in the early 1990s, the lowest social class (defined by employment or income) had more caloric intake than did the highest social class; 20 years later, however, the relation reversed, and the lowest social class consumed significantly fewer calories.

Conclusions: China has seen a great reversal in its social class-nutrition relationship since the early 1990s. Our study calls for wider recognition that insufficient consumption of food and nutrition is increasingly an issue for people in the lower social classes in China.
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http://dx.doi.org/10.2105/AJPH.2017.304001DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5637664PMC
November 2017

Health Care Decisions among Mental Health Services Consumers in San Diego County: Implications for Integrated Care.

Health Soc Work 2017 02;42(1):48-56

Division of Health Policy, Department of Family Medicine and Public Health, University of California, San Diego, USA.

People living with serious mental illness are at elevated risk for chronic diseases compared with those in the general population. Whether integrated care for this population would be most accessible in primary care or mental health settings is unclear. The cross-sectional study described in this article used descriptive analyses and multinomial logistic regression to assess factors associated with using physical health services from primary or mental health providers. Data were drawn from a large-scale assessment of client-reported use of primary care services in a large and ethnically diverse public mental health system. Most people (80.4 percent) reported accessing primary care services from one or more service settings. Having chronic conditions was associated with accessing physical health care from multiple service settings, whereas having poor self-rated emotional health decreased health services use from any setting. It was concluded that mental health services consumers access health care from various service settings. Social workers can play a critical role in enhancing care coordination across the mental health and primary care systems.
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http://dx.doi.org/10.1093/hsw/hlw060DOI Listing
February 2017

Psychiatric readmissions in a community-based sample of patients with mental disorders.

Psychiatr Serv 2015 May 31;66(5):551-4. Epub 2015 Mar 31.

The authors are with the Department of Family Medicine and Public Health, University of California, San Diego. Send correspondence to Dr. Gilmer (e-mail: ).

Objective: This study examined whether receipt of outpatient psychiatric services after hospital discharge was associated with reduced risk of readmission.

Methods: Treatment records from patients admitted to San Diego County psychiatric hospitals over a one-year period were obtained from the San Diego County Behavioral Health Services electronic health record system. A discrete-time proportional hazards model was used to examine the association of receipt of outpatient psychiatric services with readmission within 30 days of discharge from the index hospitalization.

Results: Of the 4,663 patients, 16% were readmitted within 30 days. In an adjusted model, receipt of outpatient therapy after discharge was associated with a greater likelihood of being readmitted (hazard ratio=1.36, 95% confidence interval=1.14-1.67), whereas receipt of case management or medication management was not associated with readmission.

Conclusions: The differential risk of readmission by service type suggests a need for studies that explore reasons for an increased risk of readmission with certain types of services.
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http://dx.doi.org/10.1176/appi.ps.201400092DOI Listing
May 2015

Do black-white racial disparities in breastfeeding persist in the military community?

Matern Child Health J 2015 Feb;19(2):419-27

Institute for Social Science Research (ISSR), University of Massachusetts, Amherst, MA, USA,

We conduct a comparative analysis of breastfeeding behavior between military and civilian-affiliated mothers. Our focus is on African American mothers among whom breastfeeding rates are lowest. The military context may mitigate conditions associated with low breastfeeding prevalence by (a) providing stable employment and educational opportunities to populations who face an otherwise poor labor market and (b) providing universal healthcare that includes breastfeeding consultation. Using pregnancy risk assessment monitoring system (PRAMS) data for which we received special permission from each state to flag military affiliation, we analyze civilians and military affiliate in breastfeeding initiation using logistic regression and breastfeeding duration using Cox proportional hazard analysis. We find that breastfeeding is more prevalent among all women in the military setting and that the black-white gap in breastfeeding duration common among civilians is significantly reduced among military affiliates. Breastfeeding is a crucial component of maternal and child health and eliminating racial disparities in its prevalence is a public health priority. This study is the first to identify the military as an important institutional context that deserves closer examination to glean potential policy implications for civilian society.
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http://dx.doi.org/10.1007/s10995-014-1524-xDOI Listing
February 2015

Repair of critical size bone defects with porous poly(D,L-lactide)/nacre nanocomposite hollow scaffold.

Saudi Med J 2012 Jun;33(6):601-7

Department of Spine Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, Guangdong Province, China.

Objective: To generate a novel porous poly(D,L-lactide)/nacre nanocomposite hollow scaffold.

Methods: This study was performed in the Department of Spine Surgery, Southern Medical University, Guangzhou, China from September 2010 to September 2011. Nacre nanoparticles were prepared using a physical process and identified by x-ray diffraction and transmission electron microscopy, to generate a novel scaffold though the salt leaching processing technique. The morphology and structure properties of this scaffold were further investigated under scanning electron microscope and mechanical property testing. Additionally, the biological characteristics were evaluated by cell culture experiments in vitro. Thirty-six rabbits were randomly divided into 3 groups. The defects were implanted with/without poly(D,L-lactide)/nacre scaffold or poly(D,L-lactide) scaffold. The results were assessed by radiographs and bone mineral density to monitor bone repairing.

Results: The nacre nanoparticles were spherical in shape, with a diameter range from 45-95 nm. The scaffolds possessed an interconnected porous structure with an average pore size of 322.5+/-50.8 μm, and exhibited a high porosity (82.5 +/-0.8%), as well as good compressive strength of 4.5+/-0.25 Mpa. Primary biocompatibility experiments in vitro showed that cells adhered and proliferated well on the scaffolds. The animal study further demonstrated that the scaffolds could repair the critical size segmental bone defects in 12 weeks.

Conclusion: Newly established scaffolds may serve as a promising biomaterial for bone tissue engineering.
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June 2012

Dependence of photoacoustic speckles on boundary roughness.

J Biomed Opt 2012 Apr;17(4):046009

Washington University, Optical Imaging Laboratory, Department of Biomedical Engineering, 1 Brookings Drive, Saint Louis, Missouri 63130, USA.

Speckles have been considered ubiquitous in all scattering-based coherent imaging technologies. However, as an optical-absorption-based coherent imaging technology, photoacoustic (PA) tomography (PAT) suppresses speckles by building up prominent boundary signals. We theoretically study the dependence of PAT speckles on the boundary roughness, which is quantified by the root-mean-squared value and the correlation length of the boundary height. Both the speckle visibility and the correlation coefficient between the reconstructed and actual boundaries are quantified. If the root-mean-squared height fluctuation is much greater than, and the height correlation length is much smaller than the imaging resolution, the reconstructed boundaries become fully developed speckles. In other words, speckle formation requires large uncorrelated height fluctuations within the resolution cell. The first- and second-order statistics of PAT speckles are also studied experimentally. While the amplitude of the speckles follows a Gaussian distribution, the autocorrelation of the speckle patterns tracks that of the system point spread function.
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http://dx.doi.org/10.1117/1.JBO.17.4.046009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3380940PMC
April 2012

In vivo photoacoustic tomography of mouse cerebral edema induced by cold injury.

J Biomed Opt 2011 Jun;16(6):066020

Washington University, Optical Imaging Laboratory, Department of Biomedical Engineering, St. Louis, Missouri 63130-4899, USA.

For the first time, we have implemented photoacoustic tomography (PAT) to image the water content of an edema in vivo. We produced and imaged a cold-induced cerebral edema transcranially, then obtained blood vessel and water accumulation images at 610 and 975 nm, respectively. We tracked the changes at 12, 24, and 36 h after the cold injury. The blood volume decreased after the cold injury, and the maximum area of edema was observed 24 h after the cold injury. We validated PAT of the water content of the edema through magnetic Resonance Imaging and the water spectrum from the spectrophotometric measurement.
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http://dx.doi.org/10.1117/1.3584847DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3124533PMC
June 2011

Receptor modeling of PM2.5, PM10 and TSP in different seasons and long-range transport analysis at a coastal site of Tianjin, China.

Sci Total Environ 2010 Sep 23;408(20):4681-94. Epub 2010 Jul 23.

College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, PR China.

Atmospheric particulate matter (PM(2.5), PM(10) and TSP) were sampled synchronously during three monitoring campaigns from June 2007 to February 2008 at a coastal site in TEDA of Tianjin, China. Chemical compositions including 19 elements, 6 water-solubility ions, organic and elemental carbon were determined. principle components analysis (PCA) and chemical mass balance modeling (CMB) were applied to determine the PM sources and their contributions with the assistance of NSS SO(4)(2)(-), the mass ratios of NO(3)(-) to SO(4)(2)(-) and OC to EC. Air mass backward trajectory model was compared with source apportionment results to evaluate the origin of PM. Results showed that NSS SO(4)(2)(-) values for PM(2.5) were 2147.38, 1701.26 and 239.80 ng/m(3) in summer, autumn and winter, reflecting the influence of sources from local emissions. Most of it was below zero in summer for PM(10) indicating the influence of sea salt. The ratios of NO(3)(-) to SO(4)(2)(-) was 0.19 for PM(2.5), 0.18 for PM(10) and 0.19 for TSP in winter indicating high amounts of coal consumed for heating purpose. Higher OC/EC values (mostly larger than 2.5) demonstrated that secondary organic aerosol was abundant at this site. The major sources were construction activities, road dust, vehicle emissions, marine aerosol, metal manufacturing, secondary sulfate aerosols, soil dust, biomass burning, some pharmaceutics industries and fuel-oil combustion according to PCA. Coal combustion, marine aerosol, vehicular emission and soil dust explained 5-31%, 1-13%, 13-44% and 3-46% for PM(2.5), PM(10) and TSP, respectively. Backward trajectory analysis showed air parcels originating from sea accounted for 39% in summer, while in autumn and winter the air parcels were mainly related to continental origin.
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http://dx.doi.org/10.1016/j.scitotenv.2010.06.005DOI Listing
September 2010

Photoacoustic tomography of water in phantoms and tissue.

J Biomed Opt 2010 May-Jun;15(3):036019

Washington University, Department of Biomedical Engineering, Optical Imaging Laboratory, St Louis, Missouri 63130-4899, USA.

Photoacoustic tomography (PAT) has been widely used to image optically absorptive objects in both human and animal tissues. For the first time, we present imaging of water with laser-based PAT. We photoacoustically measure the absorption spectra of water-ethanol mixtures at various water concentrations, and then image water-ethanol and pure-water inclusions in gel and a water inclusion in fat tissue. The significant difference in photoacoustic signals between water and fat tissue indicates that the laser-based PAT has the potential to detect water content in tissue.
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http://dx.doi.org/10.1117/1.3443793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2904025PMC
October 2010

Singular value decomposition-based analysis on fluorescence molecular tomography in the mouse atlas.

Annu Int Conf IEEE Eng Med Biol Soc 2009 ;2009:3739-42

Tsinghua University, Beijing, P.R.China.

The application of CCD camera improves the quality of fluorescence molecular tomography (FMT). However, large size of data set offered by CCD might increase the computational burden in the reconstruction. To balance the data size and reconstruction quality, singular value decomposition (SVD)-based analysis is applied. Simulation is performed with mouse atlas. By observing the relative gain of number of effective SVD components and reconstruction results, we find that the minimum field of view can be obtained for each projection in order to realize the optimization of experimental setup and furthest utilize data set.
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http://dx.doi.org/10.1109/IEMBS.2009.5334883DOI Listing
April 2010

A monte-carlo-based network method for source positioning in bioluminescence tomography.

Int J Biomed Imaging 2007 ;2007:48989

Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China.

We present an approach based on the improved Levenberg Marquardt (LM) algorithm of backpropagation (BP) neural network to estimate the light source position in bioluminescent imaging. For solving the forward problem, the table-based random sampling algorithm (TBRS), a fast Monte Carlo simulation method we developed before, is employed here. Result shows that BP is an effective method to position the light source.
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http://dx.doi.org/10.1155/2007/48989DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2216075PMC
July 2011

CD28 activation does not down-regulate Cbl-b expression in aged rat T-lymphocytes.

Mech Ageing Dev 2004 Sep;125(9):595-602

Division of Nutritional Sciences, The University of Texas at Austin, 78712, USA.

It is well known that T-lymphocyte proliferation declines ex vivo with age, and is associated with decreased expression and/or activity of stimulatory intracellular signaling proteins. However, the role of inhibitory intracellular signaling molecules like the ubiquitin ligase Cbl-b in regulating T-lymphocyte function in aging is largely unknown. Therefore, we tested the hypothesis that T-lymphocyte proliferation declines with age, in part, due to increased expression of Cbl-b. We show that young splenic T-lymphocytes reduced Cbl-b expression when stimulated with anti-CD3 and anti-CD28 antibodies, while in aged T-lymphocytes the CD28-dependent Cbl-b down-regulation did not occur. This effect did not appear to be due to reduced CD28 receptor expression on aged T-lymphocytes. The mechanism for lack of Cbl-b down-regulation may involve the proteasome since blocking proteasomal activity in young T-lymphocytes prevented Cbl-b down regulation while there was no effect in aged T-lymphocytes on Cbl-b expression. These data provide evidence for a novel mechanism by which aging reduces T-lymphocyte function.
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http://dx.doi.org/10.1016/j.mad.2004.06.007DOI Listing
September 2004

DNA analysis in a suspected individual with myotonic dystrophy family history and her abortus.

Chin Med J (Engl) 2002 Nov;115(11):1628-31

Department of Neurology, Changhai Hospital, The Second Military Medical University, Shanghai 200433, China.

Objective: To observe trinucleotide repeat number, (CTG)n in the 3'-untranslated region of the myotonic protein kinase (MTPK) gene in a clinically suspected woman with myotonic dystrophy (DM) family history and her abortus, in order to confirm the necessity of exerting antenatal examination in patients or suspected individuals with DM family history.

Methods: Long Expand Template polymerase chain reaction (PCR) system was used to analyze CTG trinucleotide repeat numbers located in the 3' untranslated region of MTPK on chromosome 19q13.2-3 in both peripheral white cells and muscles of the suspected mother and the other two DM patients in the family. The tissues of her abortus and blood of a health woman were detected, too.

Results: CTG repeats in both peripheral white cells and muscles of the suspected mother and the tissue of abortus were higher than normal range of CTG repeat number. There is no significant difference between blood and muscle samples. High CTG repeats were detected in blood and muscles of the typical DM members in the family, but in the blood sample of control, CTG repeats is normal.

Conclusion: CTG trinucleotide analyses and antenatal examination should be done in pregnant with a DM family history, in order to reduce the birth rate of DM offspring.
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November 2002