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1.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(1): 31-36, 2021 Jan 11.
Article in Zh | MEDLINE | ID: mdl-33429483

ABSTRACT

Objective: To investigate the related factors of myocardial fibrosis in patients with hypertrophic cardiomyopathy. Methods: Patients with hypertrophic cardiomyopathy, hospitalized in the First People's Hospital of Yunnan Province from January 2016 to May 2020, were included in this cross-sectional study. Patients were divided into delayed enhancement positive group (fibrosis group) and non-delayed enhancement group (non-fibrosis group). According to the maximum left ventricular end diastolic wall thickness (LVMWT), patients in the fibrosis group was further divided into mild hypertrophy group, moderate hypertrophy group and severe hypertrophy group. The baseline clinical data of patients were collected by medical record management system. All enrolled patients underwent cardiac magnetic resonance imaging (CMR). The presence and location of myocardial fibrosis were identified by CMR gadolinium contrast delayed enhancement (LGE). The range of LGE (LGE%) was calculated by visual analysis. The levels of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and cardiac troponin I (cTnI) in peripheral blood were measured. Results: A total of 48 patients ( age (46.4±14.3) years, 42 (87.5%) males) were enrolled. There were 34 LGE positive cases (fibrosis group) and 14 LGE negative cases (non-fibrosis group). Compared with non-fibrosis group, patients in fibrosis group were younger (P=0.038) and prevalence of NYHA grade Ⅲ/Ⅳ was higher (P=0.00). Compared with non-fibrosis group, patients in fibrosis group had thicker LVMWT (P= 0.008), higher left ventricular mass index(LVMI) (P=0.001), higher left ventricular end diastolic volume (LVEDV) (P=0.043), lower left ventricular ejection fraction (LVEF) and cardiac index (CI) (all P <0.05). The levels of NT-proBNP and cTnI were significantly higher in fibrosis group than in non-fibrosis group (2 760.5 (1 503.4, 3 783.6) ng / L vs. 861.3 (552.2, 1 092.8) ng / L, P=0.002; 0.970 (0.448, 1.684)µg / L vs. 0.147 (0.033, 0.251)µg / L, P=0.041).In fibrosis group, there were 15 cases of mild hypertrophy (mild hypertrophy group), 10 cases of moderate hypertrophy (moderate hypertrophy group), and 9 cases of severe hypertrophy (severe hypertrophy group). The LGE% and NT-proBNP and cTnI increased in proportion with increasing myocardial hypertrophy (P<0.05). LGE% was negatively correlated with age (r=-0.618, P=0.011), and positively correlated with NT-proBNP and cTnI levels (r=0.271, P=0.010; r=0.111,P=0.013, respectively), and positively correlated with LVEDV, LVMWT and LVMI (r=0.438, P=0.09; r=0.735, P=0.001; r=0.532, P=0.034, respectively). Conclusions: In patients with hypertrophic cardiomyopathy, the extent of myocardial fibrosis increases with the increase of myocardial hypertrophy. Myocardial fibrosis is negatively correlated with age, and positively correlated with NT-proBNP and cTnI, as well as LVEDV, LVMWT and LVMI in this patient cohort.

2.
Lupus ; 29(2): 165-175, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31964222

ABSTRACT

With potent immunomodulatory activities, mesenchymal stem cells (MSCs) have the potential to be a beneficial treatment option for diseases with aberrant immune responses such as systemic lupus erythematosus (SLE). However, the underlying mechanisms remain largely unknown. Here, we used NZBWF1 mice as a SLE animal model to examine immunomodulation of MSCs as well as to assess the role of Toll-like receptor signalling in this circumstance. We found that mice receiving MSCs had a significant decrease in severity of proteinuria at 20 and 22 weeks of age (p = 0.009 and p = 0.022, respectively). Serum anti-dsDNA levels were significantly lower compared with the control group (p = 0.016 and p = 0.036, respectively). C3 and C4 levels were significantly higher at 22 weeks of age (p = 0.046 and p = 0.016, respectively). Altered expression of inflammation-associated cytokine profiles in the serum was also noted in mice receiving MSCs. Down-regulation of myeloid differentiation factor 88 (MyD88)-nuclear factor-κB (NF-κB) signalling in the liver was demonstrated by quantitative polymerase chain reaction, ELISA and Western blotting. In addition to demonstrating the beneficial effects of MSC treatment in NZBWF1 mice, our study provided the first evidence for the association of MyD88-NF-κB signalling and MSC-mediated immunomodulation in this disease.


Subject(s)
Lupus Erythematosus, Systemic/therapy , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology , Toll-Like Receptors/immunology , Animals , Disease Models, Animal , Down-Regulation , Female , Immunomodulation , Inflammation/therapy , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/pathology , Mice , Myeloid Differentiation Factor 88/immunology , Signal Transduction/immunology , Umbilical Cord/cytology
3.
Osteoporos Int ; 29(12): 2645-2658, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30306226

ABSTRACT

By integrating the multilevel biological evidence and bioinformatics analyses, the present study represents a systemic endeavor to identify BMD-associated genes and their roles in skeletal metabolism. INTRODUCTION: Single-nucleotide polymorphism (SNP)-based genome-wide association studies (GWASs) have already identified about 100 loci associated with bone mineral density (BMD), but these loci only explain a small proportion of heritability to osteoporosis risk. In the present study, we performed a gene-based analysis of the largest GWASs in the bone field to identify additional BMD-associated genes. METHODS: BMD-associated genes were identified by combining the summary statistic P values of SNPs across individual genes in the two consecutive meta-analyses of GWASs from the Genetic Factors for Osteoporosis (GEFOS) studies. The potential functionality of these genes to bone was partially assessed by differential gene expression analysis. Additionally, the consistency of the identification of potential bone mineral density (BMD)-associated variants were evaluated by estimating the correlation of the P values of the same single-nucleotide polymorphisms (SNPs)/genes between the two consecutive Genetic Factors for Osteoporosis Studies (GEFOS) with largely overlapping samples. RESULTS: Compared to the SNP-based analysis, the gene-based strategy identified additional BMD-associated genes with genome-wide significance and increased their mutual replication between the two GEFOS datasets. Among these BMD-associated genes, three novel genes (UBTF, AAAS, and C11orf58) were partially validated at the gene expression level. The correlation analysis presented a moderately high between-study consistency of potential BMD-associated variants. CONCLUSIONS: Gene-based analysis as a supplementary strategy to SNP-based genome-wide association studies, when applied here, is shown that it helped identify some novel BMD-associated genes. In addition to its empirically increased statistical power, gene-based analysis also provides a higher testing stability for identification of BMD genes.


Subject(s)
Bone Density/genetics , Osteoporosis/genetics , Polymorphism, Single Nucleotide , Databases, Genetic , Gene Expression Profiling/methods , Gene Expression Regulation/physiology , Genetic Predisposition to Disease , Genome-Wide Association Study/methods , Humans
4.
Osteoporos Int ; 28(5): 1699-1709, 2017 05.
Article in English | MEDLINE | ID: mdl-28236128

ABSTRACT

Low bone mineral density (BMD) and osteoporosis have become a public health problem. We found that non-Hispanic white, black, and Asian adults with extremely low education and personal income are more likely to have lower BMD. This relationship is gender-specific. These findings are valuable to guide bone health interventions. INTRODUCTION: The evidence is limited regarding the relationship between socioeconomic status (SES) and bone mineral density (BMD) for minority populations in the USA, as well as the relationship between SES and BMD for men. This study explored and examined the relationship between SES and BMD by race/ethnicity and gender. METHODS: Data (n = 6568) from the Louisiana Osteoporosis Study (LOS) was examined, including data for non-Hispanic whites (n = 4153), non-Hispanic blacks (n = 1907), and non-Hispanic Asians (n = 508). General linear models were used to estimate the relationship of SES and BMD (total hip and lumbar spine) stratified by race/ethnicity and gender. Adjustments were made for physiological and behavioral factors. RESULTS: After adjusting for covariates, men with education levels below high school graduate experienced relatively low hip BMD than their counterparts with college or graduate education (p < 0.05). In addition, women reporting a personal annual income under $20,000 had relatively low hip and spine BMD than their counterparts with higher income level(s) (p < 0.05). CONCLUSIONS: Establishing a conclusive positive or negative association between BMD and SES proved to be difficult. However, individuals who are at an extreme SES disadvantage are the most vulnerable to have relatively low BMD in the study population. Efforts to promote bone health may benefit from focusing on men with low education levels and women with low individual income.


Subject(s)
Bone Density/physiology , Osteoporosis/ethnology , Social Class , Absorptiometry, Photon/methods , Adult , Black or African American/statistics & numerical data , Asian/statistics & numerical data , Cross-Sectional Studies , Educational Status , Female , Humans , Income , Louisiana/epidemiology , Male , Middle Aged , Osteoporosis/physiopathology , Sex Factors , White People/statistics & numerical data
5.
Osteoporos Int ; 28(3): 1035-1046, 2017 03.
Article in English | MEDLINE | ID: mdl-27844135

ABSTRACT

In male Caucasians with discordant hip bone mineral density (BMD), we applied the subcellular separation and proteome profiling to investigate the monocytic cytosol. Three BMD-associated proteins (ALDOA, MYH14, and Rap1B) were identified based on multiple omics evidence, and they may influence the pathogenic mechanisms of osteoporosis by regulating the activities of monocytes. INTRODUCTION: Osteoporosis is a serious public health problem, leading to significant mortality not only in aging females but also in males. Peripheral blood monocytes (PBMs) play important roles in bone metabolism by acting as precursors of osteoclasts and producing cytokines important for osteoclast development. The first cytosolic sub-proteome profiling analysis was performed in male PBMs to identify differentially expressed proteins (DEPs) that are associated with BMDs and risk of osteoporosis. METHODS: Here, we conducted a comparative proteomics analysis in PBMs from Caucasian male subjects with discordant hip BMD (29 low BMD vs. 30 high BMD). To decrease the proteome complexity and expand the coverage range of the cellular proteome, we separated the PBM proteome into several subcellular compartments and focused on the cytosolic fractions, which are involved in a wide range of fundamental biochemical processes. RESULTS: Of the total of 3796 detected cytosolic proteins, we identified 16 significant (P < 0.05) and an additional 22 suggestive (P < 0.1) DEPs between samples with low vs. high hip BMDs. Some of the genes for DEPs, including ALDOA, MYH14, and Rap1B, showed an association with BMD in multiple omics studies (proteomic, transcriptomic, and genomic). Further bioinformatics analysis revealed the enrichment of DEPs in functional terms for monocyte proliferation, differentiation, and migration. CONCLUSIONS: The combination strategy of subcellular separation and proteome profiling allows an in-depth and refined investigation into the composition and functions of cytosolic proteome, which may shed light on the monocyte-mediated pathogenic mechanisms of osteoporosis.


Subject(s)
Cytosol/metabolism , Monocytes/metabolism , Osteoporosis/blood , Proteome/metabolism , Absorptiometry, Photon , Adult , Bone Density/genetics , Bone Density/physiology , Fructose-Bisphosphate Aldolase/biosynthesis , Fructose-Bisphosphate Aldolase/genetics , Gene Expression Profiling/methods , Gene Expression Regulation/physiology , Gene Ontology , Gene Regulatory Networks/physiology , Humans , Male , Middle Aged , Myosin Heavy Chains/biosynthesis , Myosin Heavy Chains/genetics , Myosin Type II/biosynthesis , Myosin Type II/genetics , Osteoporosis/genetics , Osteoporosis/physiopathology , Proteome/genetics , Proteomics/methods , rap GTP-Binding Proteins/biosynthesis , rap GTP-Binding Proteins/genetics
6.
Transfus Med ; 26(5): 349-354, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27634577

ABSTRACT

OBJECTIVES: To evaluate the clinical significance of GP. Mur antigen-negative blood selection for transfusion in patients with anti-'Mia ' records. BACKGROUND: The GP. Mur RBC phenotype is prevalent (7·3%) in Taiwan. Antibodies against GP. Mur (anti-'Mia ') are identified in 1·24% of our population, and anti-'Mia ' screening using GP. Mur RBC has been routine for Taiwan's blood banks. However, due to the lack of commercial antibodies, only cross-matching was used to prevent transfusion of GP. Mur-positive blood to patients with anti-'Mia ' in most hospitals. There is still a risk of GP. Mur-positive RBC exposure and subsequent anti-'Mia '-related transfusion reactions. METHODS: Since February 2014, GP. Mur antigen-negative RBCs identified by reaction with anti-'Mia '-positive serum were selected for blood recipients with anti-'Mia ' records. The transfusion reactions between January 2013 and January 2014 were compared with those that occurred between February 2014 and July 2015. RESULTS: The transfusion reaction rate was significantly higher in anti-'Mia '-positive blood recipients compared to total subjects receiving an RBC transfusion before GP. Mur-negative donor RBC selection. After antigen-negative RBC selection, the transfusion reaction frequency in subjects with anti-'Mia ' became similar to total blood recipients. IgG form anti-'Mia ' antibodies were present in all cases of probable anti-'Mia '-related transfusion reactions. The time required for anti-'Mia ' boosting after transfusion was around 4-21 days. CONCLUSION: Selection of GP. Mur-negative RBC for transfusion to patients with anti-'Mia ' records could decrease the rate of transfusion reaction and antibody boosting. This procedure should be incorporated into blood bank routines in areas where anti-'Mia ' is prevalent.


Subject(s)
Blood Donors , Blood Group Antigens/blood , Blood Grouping and Crossmatching/methods , Donor Selection/methods , Erythrocytes/metabolism , Glycophorins/metabolism , Isoantibodies/blood , Erythrocytes/cytology , Female , Humans , Male
7.
Curr Oncol ; 23(4): e431-4, 2016 Aug.
Article in English | MEDLINE | ID: mdl-27536191

ABSTRACT

Hypopituitarism in leukemia is very rare. In addition, central nervous system (cns) relapse and leukemic retinopathy in childhood acute lymphoblastic leukemia (all) have declined with the use of modern systemic chemotherapy that includes cns prophylaxis. Here, we report the case of a 4-year-old girl who received chemotherapy and intrathecal therapy without cns radiation after a diagnosis of B-precursor all without cns involvement. Three months after chemotherapy completion, she presented with lower-extremity weakness and was diagnosed with an isolated cns relapse. Concurrent hypopituitarism and leukemic retinopathy were also found. After receiving craniospinal radiotherapy and systemic chemotherapy, her retinopathy and vision improved. She is now in complete remission, and she is still on chemotherapy according to the guideline from the Pediatric Oncology Group. Although rare, hypopituitarism and leukemic retinopathy should be taken into consideration in patients with cns involvement by leukemia.

8.
Curr Oncol ; 22(4): 303-6, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26300669

ABSTRACT

Imatinib has improved outcomes in patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (all). Minimal residual disease (mrd) is a useful tool for predicting leukemia relapse. However, there is no consensus on how to treat children with elevation of BCR-ABL transcripts but no evidence of hematologic relapse during chemotherapy combined with imatinib. Here, we report the case of a child with Ph+ all who had persistent elevation of mrd, but no evidence of hematologic relapse while receiving imatinib plus intensive chemotherapy. Dasatinib was substituted for imatinib because no suitable donor for allogeneic hematopoietic stem-cell transplantation (hsct) was available. Less-intensive chemotherapy with methotrexate and 6-mercaptopurine was administered concomitantly. No serious adverse events were encountered. With continuous dasatinib combined with chemotherapy, but no allogeneic hsct, our patient reached complete molecular remission and has been in complete molecular remission for more than 13 months. This report is the first about the long-term use of dasatinib in patients with Ph+ all and mrd elevation but hematologic remission during imatinib chemotherapy. In a similar situation, chemotherapy combined with dasatinib instead of allogeneic hsct could be considered to avoid hsct-related mortality and morbidity. Clinical trials are needed.

9.
Nano Lett ; 13(12): 5797-802, 2013.
Article in English | MEDLINE | ID: mdl-24228733

ABSTRACT

The recent focus on topological insulators is due to the scientific interest in the new state of quantum matter as well as the technology potential for a new generation of THz optoelectronics, spintronics and quantum computations. It is important to elucidate the dynamics of the Dirac fermions in the topologically protected surface state. Hence we utilized a novel ultrafast optical pump mid-infrared probe to explore the dynamics of Dirac fermions near the Dirac point. The femtosecond snapshots of the relaxation process were revealed by the ultrafast optics. Specifically, the Dirac fermion-phonon coupling strength in the Dirac cone was found to increase from 0.08 to 0.19 while Dirac fermions were away from the Dirac point into higher energy states. Further, the energy-resolved transient reflectivity spectra disclosed the energy loss rate of Dirac fermions at room temperature was about 1 meV/ps. These results are crucial to the design of Dirac fermion devices.


Subject(s)
Nanostructures/chemistry , Nanotechnology , Optics and Photonics , Quantum Theory , Semiconductors , Spectrophotometry, Infrared
10.
Opt Express ; 21(12): 13930-7, 2013 Jun 17.
Article in English | MEDLINE | ID: mdl-23787582

ABSTRACT

This study systematically investigates the influence of free carriers on the generation of THz in ZnTe crystals, over a wide range of pumping fluences. As the pumping fluence is increased (< 6.36 mJ/cm(2)), the concentration of free carriers gradually increases and the THz output power is saturated, as clearly demonstrated by the time delay in the THz temporal waveforms, the changes in the THz spectral weight and the red-shift in the PL spectra. For high pumping fluences (> 6.36 mJ/cm(2)), spectacularly, there is a significant quadratic increase in the THz output power when the pumping fluence is increased, as well as at low pumping fluences of < 0.58 mJ/cm(2), because of the saturation of free carriers.


Subject(s)
Tellurium/chemistry , Tellurium/radiation effects , Zinc/chemistry , Zinc/radiation effects , Crystallization , Electron Transport , Materials Testing , Scattering, Radiation , Terahertz Radiation
11.
Klin Padiatr ; 225(1): 18-23, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23329622

ABSTRACT

This study aimed to analyze the epidemiologic patterns of pediatric critically-ill patients presenting to the emergency department (ED) and the etiologies of intensive care unit (ICU) admission of different age groups.This retrospective study of all children aged less than 18 years presenting with critical illnesses to the ED was conducted in a tertiary medical center in Taiwan from 2003 to 2007. All patients transferred to the ICU from the ED were included without distinction. Demographic data of critically-ill children admitted to the ED and ICU were analyzed. Etiologies of the ICU admissions were analyzed by various age groups.There were 2978 critically-ill children admitted to the ICU from the ED. In 120 pediatric patients with out-of-hospital cardiac arrest, cases with pulseless electrical activity or ventricular fibrillation had higher successful CPR rates than patients with asystole (both p<0.05). In patients admitted to ICUs, complications from the perinatal period, respiratory system diseases, accidental injuries and poisoning were the predominant etiologies respectively in young children (42.5%), school-aged children (38.5%), and adolescents (47.9%). Moreover, the most common of which was respiratory distress syndrome in neonates followed by bacterial pneumonia and status epilepticus.Epidemiologic analysis may provide primary clinicians to identify significant differences in admission rates based on different etiologies of various age groups.


Subject(s)
Critical Illness/epidemiology , Emergency Service, Hospital/statistics & numerical data , Intensive Care Units, Pediatric/statistics & numerical data , Academic Medical Centers/statistics & numerical data , Adolescent , Causality , Child , Child, Preschool , Cross-Sectional Studies , Emergency Medical Services/statistics & numerical data , Female , Humans , Infant , Infant, Newborn , Male , Patient Admission/statistics & numerical data , Resuscitation/statistics & numerical data , Taiwan , Wounds and Injuries/epidemiology
12.
Nano Lett ; 12(11): 5845-9, 2012 Nov 14.
Article in English | MEDLINE | ID: mdl-23102267

ABSTRACT

Using atomically and momentum resolved scanning tunneling microscopy and spectroscopy, we demonstrate that a two-dimensional (2D) √3 × âˆš3 semiconducting Ga-Si single atomic alloy layer exhibits an electronic structure with atomic localization and which is different at the Si and Ga atom sites. No indication of an interaction or an electronic intermixing and formation of a new alloy band structure is present, as if no alloying happened. The electronic localization is traced back to the lack of intra alloy bonds due to the 2D atomically confined structure of the alloy overlayer.

13.
Phys Rev Lett ; 108(25): 257006, 2012 Jun 22.
Article in English | MEDLINE | ID: mdl-23004646

ABSTRACT

Quasiparticle dynamics of FeSe single crystals revealed by dual-color transient reflectivity measurements (ΔR/R) provides unprecedented information on Fe-based superconductors. The amplitude of the fast component in ΔR/R clearly gives a competing scenario between spin fluctuations and superconductivity. Together with the transport measurements, the relaxation time analysis further exhibits anomalous changes at 90 and 230 K. The former manifests a structure phase transition as well as the associated phonon softening. The latter suggests a previously overlooked phase transition or crossover in FeSe. The electron-phonon coupling constant λ is found to be 0.16, identical to the value of theoretical calculations. Such a small λ demonstrates an unconventional origin of superconductivity in FeSe.

14.
Epidemiol Infect ; 140(8): 1454-60, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22000033

ABSTRACT

This study aimed to investigate the relationship between hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in the ovary and vertical transmission of HBV. HBV DNA and HBV cccDNA were assayed in the ovaries of 33 pregnant women who were positive for HBV DNA. The HBVM (HBV markers, including HBsAg, HBsAb, HBeAg, HBeAb, HBcAb) level and the HBV DNA content in peripheral blood of infants were measured. The overall positive rate of HBV DNA and HBV cccDNA in samples was 51·52% (17/33). The intrauterine infection rate of the infants was 12·12% (4/33). When HBV DNA and HBV cccDNA were both positive, the intrauterine infection rate of infants was significantly higher than when they were both negative (P<0·05). Levels of HBV cccDNA and the rate of positive samples were significantly higher in mothers with infants with intrauterine infection than in those without (P<0·01 and P<0·05, respectively). HBV can infect the human ovary and may transmit to the filial generation via the ovum.


Subject(s)
DNA, Circular/genetics , DNA, Viral/genetics , Hepatitis B virus/genetics , Hepatitis B/transmission , Infectious Disease Transmission, Vertical , Ovary/virology , Adult , DNA, Viral/blood , Female , Gene Expression Regulation, Viral/physiology , Humans , Infant , Infant, Newborn , Pregnancy , Young Adult
15.
Phys Rev Lett ; 105(17): 176602, 2010 Oct 22.
Article in English | MEDLINE | ID: mdl-21231064

ABSTRACT

We report that Bi2Se3 thin films can be epitaxially grown on SrTiO3 substrates, which allow for very large tunablity in carrier density with a back gate. The observed low field magnetoconductivity due to weak antilocalization (WAL) has a very weak gate-voltage dependence unless the electron density is reduced to very low values. Such a transition in WAL is correlated with unusual changes in longitudinal and Hall resistivities. Our results suggest a much suppressed bulk conductivity at large negative gate voltages and a possible role of surface states in the WAL phenomena.

16.
J Phys Condens Matter ; 21(2): 026013, 2009 Jan 14.
Article in English | MEDLINE | ID: mdl-21814006

ABSTRACT

We investigated the magnetic and ferroelectric properties of c-axis oriented orthorhombic phase HoMnO(3) (o-HMO in Pbnm symmetry setting) thin films grown on Nb-doped SrTiO(3)(001) substrates. The o-HMO films exhibit an antiferromagnetic ordering near 42 K, irrespective of the orientation of the applied field. However, an additional magnetic ordering occurring around 35 K was observed when the field was applied along the c-axis of o-HMO, which was absent when the field was applied in the ab-plane. The magnetocapacitance measured along the c-axis showed that although there is evidence of dielectric constant enhancement when the temperature is below 35 K the expected abrupt change in dielectric constant appears at a much lower temperature and reaches maximum around 13.5 K, indicating that the low-temperature c-axis polarization might be related to the ordering of the Ho(3+) moment. The lattice constant analyses using x-ray diffraction and the observation of a slight magnetization hysteresis suggest that the weak second magnetic transition along the c-axis at 35 K might be more relevant to the strain-induced effect on antiferromagnetism.

17.
Polym Degrad Stab ; 94(9): 1411-1418, 2009 Sep.
Article in English | MEDLINE | ID: mdl-32287516

ABSTRACT

Nanohybrid membranes based on the Keggin-type polyoxometalate (POM) H5PV2Mo10O40 and a poly(vinyl alcohol)/polyethyleneimine (PVA/PEI) blend were prepared as a chemical and biological protective material. The objective of the study was to develop and evaluate permeable membranes (PVA/PEI) impregnated with reactive nanoparticulates (POM) that can protect against simulants of chemical and biological warfare agents. The physical properties of the PVA/PEI-POM hybrids were examined using SEM, TEM, TGA, and UV-Vis spectroscopy, the results of which indicated that the POM was incorporated in the PVA/PEI matrix after impregnation. The redox properties against 2-chloroethyl-ethyl sulfide (CEES) were investigated based on significant color changes and UV absorption in the POM upon reduction by CEES. The antibacterial effects of the PVA/PEI-POM hybrids were assessed by the zone of inhibition, minimum inhibitory concentration (MIC), and plate-counting methods. The results of this study showed that PVA/PEI-POM hybrids that act against simulants of chemical and biological weapons while retaining their ability to transmit moisture vapor could be obtained.

18.
Opt Express ; 16(5): 3305-9, 2008 Mar 03.
Article in English | MEDLINE | ID: mdl-18542419

ABSTRACT

We report a collinear output and tunable dual-wavelength CW Ti:sapphire laser with a simple cavity configuration. The wavelength splitting range is easily tuned from 10 nm to 110 nm, which provides 56 THz bandwidth for terahertz generation. The total output power of two colors with the spatial mode of TEM(00) is between 700 mW and 300 mW, for small and large wavelength splittings, respectively, under 5 W argon-ion laser pumping.


Subject(s)
Aluminum Oxide/chemistry , Lasers, Solid-State , Semiconductors , Titanium , Equipment Design , Equipment Failure Analysis
19.
Opt Express ; 16(25): 20610-6, 2008 Dec 08.
Article in English | MEDLINE | ID: mdl-19065200

ABSTRACT

We report on the formation of organized sub-micron YBa(2)Cu(3)O(7) (YBCO) dots induced by irradiating femtosecond laser pulses on YBCO films prepared by pulse laser deposition with fluence in the range of 0.21 approximately 0.53 J/cm(2). The morphology of the YBCO film surface depends strongly on the laser fluences irradiated. At lower laser fluence (approximately 0.21 J/cm(2)) the morphology was pattern of periodic ripples with sub-micrometer spacing. Slightly increasing the laser fluence to 0.26 J/cm(2) changes the pattern into organized sub-micron dots with diameters ranging from 100 nm to 800 nm and height of 150 nm. Further increase of the laser fluence to over 0.32 J/cm(2), however, appeared to result in massive melting and led to irregular morphology. The mechanism and the implications of the current findings will be discussed. Arrays of YBCO sub-micron dots with T(c) = 89.7 K were obtained.


Subject(s)
Lasers , Nanostructures/chemistry , Nanostructures/ultrastructure , Nanotechnology/methods , Nanostructures/radiation effects , Particle Size , Radiation Dosage
20.
Transplant Proc ; 39(5): 1620-2, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17580202

ABSTRACT

Recent advances suggest human umbilical cord is a new source for stem cells. Our laboratory has established a method to readily isolate and expand stem cells from human umbilical cord tissues. The aim of this study was to investigate the therapeutic potential of human umbilical cord-derived stem (UCDS) cells in ischemic diseases. The UCDS cells were characterized by flow cytometry and differentiation into osteogenic and adipogenic cells. Unilateral hind limb ischemia was surgically induced by femoral artery ligation in nude mice. The animals were intramuscularly injected with 10(6) UCDS cells or control phosphate-buffered saline. Blood perfusion of ischemic limbs was detected by laser Doppler perfusion imaging. Transplantation of UCDS cells to the ischemic limbs of nude mice significantly improved the blood flow to the affected limbs. Thus, transplantation of UCDS cells may potentially be a promising treatment for human ischemic diseases.


Subject(s)
Cord Blood Stem Cell Transplantation , Hindlimb/blood supply , Ischemia/therapy , Animals , Humans , Male , Mice , Mice, Nude , Transplantation, Heterologous , Umbilical Cord
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