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Huang SS, Liu Y, Jing ZC, Wang XJ, Mao YM. Common genetic risk factors of venous thromboembolism in Western and Asian populations. GENETICS AND MOLECULAR RESEARCH 2016; 15:15017644. [PMID: 26985940 DOI: 10.4238/gmr.15017644] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Venous thromboembolism (VTE) is a multifactorial disorder involving both acquired and genetic risk factors. The common genetic factors in Western populations have been studied and reported for several decades, while studies on Asian populations are relatively scarce. Evidence suggests that the prevalence and genetic risk factors of VTE vary significantly among ethnic populations. In this review, we summarize the common genetic risk factors of VTE in both Western and Asian populations. In addition to the development of DNA sequencing technology, genome-wide association studies have many advantages and are becoming more important in identifying new genetic risk factors and susceptible loci. They can therefore help in the prediction and prevention of VTE.
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Tsai MJ, Tsai SK, Huang MC, Liou DY, Huang SL, Hsieh WH, Huang WC, Huang SS, Cheng H. Acidic FGF promotes neurite outgrowth of cortical neurons and improves neuroprotective effect in a cerebral ischemic rat model. Neuroscience 2015; 305:238-47. [PMID: 26241340 DOI: 10.1016/j.neuroscience.2015.07.074] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 06/30/2015] [Accepted: 07/16/2015] [Indexed: 02/06/2023]
Abstract
Acidic fibroblast growth factor (aFGF) is a neurotrophic factor which is a powerful neuroprotective and neuroregenerative factor of the nervous system. Prior study had shown that levels of FGFs significantly increase following ischemic injury, reflecting a physiological protection mechanism. However, few reports demonstrated the efficacy of applying aFGF in cerebral ischemia. A recent report showed that the intranasal aFGF treatment improved neurological functional recovery; however, it did not significantly reduce the lesion size in ischemic rats. The present study examines the neuroprotective effect of aFGF on cortical neuron-glial cultures under oxygen glucose deprivation (OGD)-induced cell damage and investigates whether epidural application of slow-released aFGF could improve benefit on ischemic stroke injury in conscious rats. We used a topical application of aFGF mixed in fibrin glue, a slow-release carrier, over the peri-ischemic cortex and examined such treatment on cerebral infarction and behavioral impairments of rats subjected to focal cerebral ischemia (FCI). Results demonstrate that aFGF effectively protected cortical neuron-glial cultures from OGD-induced neuronal damage. Neurite extension from cortical neurons was significantly enhanced by aFGF, mediated through activation of AKT and ERK. In addition, topical application of fibrin glue-mixed aFGF dose-dependently reduced ischemia-induced brain infarction and improved functional restoration in ischemic stroke rats. Slow-released aFGF not only protected hippocampal and cortical cell loss but reduced microglial infiltration in FCI rats. Our results suggest that aFGF mixed in fibrin glue could prolong the protective/regenerative efficacy of aFGF to the damaged brain tissue and thus improve the functional restorative effect of aFGF.
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Meng X, Ouyang GC, Liu H, Hou BH, Huang SS, Guo MF. Molecular screening and predation evaluation of the key predators of Conopomorpha sinensis Bradley (Lepidoptera: Gracilariidae) in litchi orchards. BULLETIN OF ENTOMOLOGICAL RESEARCH 2014; 104:243-250. [PMID: 24401157 DOI: 10.1017/s0007485313000709] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Conopomorpha sinensis Bradley (Lepidoptera: Gracilariidae) is one of the major fruit borer pests of litchi and longan in Southern China. Although chemical control is effective, alternative, biorational strategies are preferable, and should be developed. Predators play an important role in the biological control of agricultural pests, but an accurate method for the evaluation of predation in agriculture has not yet been developed. Here, we report a new, specific primer pair to amplify a C. sinensis cytochrome c oxidase subunit I (COI) sequence fragment that can be used to detect consumption of C. sinensis by its predators. C. sinensis DNA was found in several arthropods collected in the field, including the important C. sinensis predators M enochilus sexmaculata (Coccinellidae), Leucauge magnifica (Tetragnathidae), Propylea japonica (Coccinellidae), and Oxyopes sertatus (Oxyopidae). The detection rates of C. sinensis COI DNA in these predators were 39.3, 36.4, 27.3, and 27.2%, respectively. Laboratory consumption and hunting capacity analysis of M. sexmaculata and P. japonica adults indicated that they exhibit a Holling type II functional response on C. sinensis eggs under field temperatures. A polymerase chain reaction digestion analysis of M. sexmaculata and P. japonica adults after consumption of a single C. sinensis egg indicated that positive detection decreased with the extension of digestion time, and estimated prey DNA half-lives were 16.3 h in M. sexmaculata and 6.0 h in P. japonica. These data serve to characterize two major predators of C. sinensis with potential for biological control of C. sinensis in litchi orchards.
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Huang JF, Chang WK, Chung HP, Huang SS, Chang JW, Chen YH. Double-prism domain PPLN for simultaneous laser Q-switching and optical parametric oscillation in a Nd:YVO4 laser. OPTICS EXPRESS 2013; 21:30370-30378. [PMID: 24514615 DOI: 10.1364/oe.21.030370] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We report a design and demonstration of an electro-optically Q-switched intracavity optical parametric oscillator (IOPO) based on a unique ramped duty-cycle periodically poled lithium niobate (PPLN) in a diode-pumped 1064-nm Nd:YVO(4) laser. The PPLN crystal, having a double-prism domain (DPD) structure with a domain period of 30 μm, can work simultaneously as an electro-optic (EO) beam deflector (and therefore an EO Q-switch in the laser cavity) and an optical parametric down converter. The characterized deflection sensitivity of the DPD PPLN device was 1.15°/kV-cm. At a 180-V Q-switching voltage and a 1-kHz switching rate, we measured a down-converted signal at 1550 nm with pulse energy of >8.1 μJ (or peak power of >2.3 kW) from the constructed IOPO at 7.5-W diode pump power. Continuous wavelength tuning of the IOPO signal was also demonstrated.
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Huang SS, Kirchoff BK, Liao JP. Effect of heat shock on ultrastructure and calcium distribution in Lavandula pinnata L. glandular trichomes. PROTOPLASMA 2013; 250:185-196. [PMID: 22418827 DOI: 10.1007/s00709-012-0393-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 02/22/2012] [Indexed: 05/31/2023]
Abstract
The effects of heat shock (HS) on the ultrastructure and calcium distribution of Lavandula pinnata secretory trichomes are examined using transmission electron microscopy and potassium antimonate precipitation. After 48-h HS at 40°C, plastids become distorted and lack stroma and osmiophilic deposits, the cristae of the mitochondria become indistinct, the endoplasmic reticulum acquires a chain-like appearance with ribosomes prominently attached to the lamellae, and the plasma and organelle membranes become distorted. Heat shock is associated with a decrease in calcium precipitates in the trichomes, while the number of precipitates increases in the mesophyll cells. Prolonged exposure to elevated calcium levels may be toxic to the mesophyll cells, while the lack of calcium in the glands cell may deprive them of the normal protective advantages of elevated calcium levels. The inequality in calcium distribution may result not only from uptake from the transpiration stream, but also from redistribution of calcium from the trichomes to the mesophyll cells.
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Lee BY, Singh A, David MZ, Bartsch SM, Slayton RB, Huang SS, Zimmer SM, Potter MA, Macal CM, Lauderdale DS, Miller LG, Daum RS. The economic burden of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA). Clin Microbiol Infect 2012; 19:528-36. [PMID: 22712729 DOI: 10.1111/j.1469-0691.2012.03914.x] [Citation(s) in RCA: 130] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The economic impact of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) remains unclear. We developed an economic simulation model to quantify the costs associated with CA-MRSA infection from the societal and third-party payer perspectives. A single CA-MRSA case costs third-party payers $2277-$3200 and society $7070-$20 489, depending on patient age. In the United States (US), CA-MRSA imposes an annual burden of $478 million to 2.2 billion on third-party payers and $1.4-13.8 billion on society, depending on the CA-MRSA definitions and incidences. The US jail system and Army may be experiencing annual total costs of $7-11 million ($6-10 million direct medical costs) and $15-36 million ($14-32 million direct costs), respectively. Hospitalization rates and mortality are important cost drivers. CA-MRSA confers a substantial economic burden on third-party payers and society, with CA-MRSA-attributable productivity losses being major contributors to the total societal economic burden. Although decreasing transmission and infection incidence would decrease costs, even if transmission were to continue at present levels, early identification and appropriate treatment of CA-MRSA infections before they progress could save considerable costs.
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Hanage WP, Bishop CJ, Lee GM, Lipsitch M, Stevenson A, Rifas-Shiman SL, Pelton SI, Huang SS, Finkelstein JA. Clonal replacement among 19A Streptococcus pneumoniae in Massachusetts, prior to 13 valent conjugate vaccination. Vaccine 2011; 29:8877-81. [PMID: 21964059 DOI: 10.1016/j.vaccine.2011.09.075] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 09/16/2011] [Accepted: 09/18/2011] [Indexed: 10/17/2022]
Abstract
As part of an ongoing study of the response of the Streptococcus pneumoniae population to conjugate vaccination, we applied multi-locus sequence typing (MLST) to 291 isolates sampled from nasopharyngeal carriage in Massachusetts children. We found 94 distinct sequence types (STs), including 19 that had not been previously recorded, and a xpt allele containing a large insertion. Comparison with a similar sample collected in 2007 revealed no significant overall difference in the ST composition (p=0.51) suggesting that the population has reached a new equilibrium following the introduction of 7 valent vaccination in 2000. Within serotypes, a large and statistically significant increase (p=0.014 Fisher's Exact test) was noted in the prevalence of the major multiresistant clone ST 320, which is apparently outcompeting ST 199 among serotype 19A strains. This sample will be used as a baseline to study the future evolution of the pneumococcal population in Massachusetts following introduction of vaccines with higher valency.
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Wang Q, Pan YZ, Huang SS, Ren ST, Li P, Li JJ. Resistive and capacitive response of nitrogen-doped TiO2 nanotubes film humidity sensor. NANOTECHNOLOGY 2011; 22:025501. [PMID: 21135473 DOI: 10.1088/0957-4484/22/2/025501] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Dielectric oxides are traditionally used to fabricate resistive surface humidity-sensing devices, as well as capacitive sandwich-structured sensors. In the present work, relative humidity (RH) sensors were fabricated by employing vertically aligned TiO(2) nanotubes array (TNA) film produced using electro-chemical anodization of Ti foil followed by a nitrogen-doping process, simultaneously showing resistive and capacitive humidity-sensing properties in the range of 11.3-93.6%. For the sample formed at optimized experimental conditions, the capacitance (C(S)) and resistance (R(S)) of the as-fabricated RH sensors made from nitrogen-doped TiO(2) nanotubes film could be simultaneously obtained. Both the resistive and capacitive sensitivity (K(R) and K(C)) of the as-fabricated TiO(2) nanotube RH sensors show distinct dependence on the frequency of alternating current (AC) voltage signal and RH. At higher water coverage, water-water interaction will result in lowering of the water dissociation barrier, leading to an increase of conductance. With the increase of RH, the polarization of as-adsorbed water molecules will also occur, causing a sharp increase of capacitance. For an explanation of the frequency response of both C(S) and R(S), ionic transport, as well as the polarization effect, should be comprehensively considered. The changes of capacitance and resistance at different temperatures are plausibly caused by thermal expansion and surface state modification by adsorption and desorption of oxygen and water.
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Zhang YY, Deng JH, He C, Huang SS, Tian SH, Xiong Y. Application of Fe2V4O13 as a new multi-metal heterogeneous Fenton-like catalyst for the degradation of organic pollutants. ENVIRONMENTAL TECHNOLOGY 2010; 31:145-154. [PMID: 20391799 DOI: 10.1080/09593330903397755] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Iron tetrapolyvanadate (Fe2V4O13) was prepared and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) measurement and scanning electron microscopy (SEM). It was found that Fe2V4O13 could effectively catalyse H2O2 to generate active OH; therefore, Fe2V4O13 was employed as a new two-metal heterogeneous Fenton-like catalyst. The decomposition of H2O2 and the degradation of Acid Orange II catalysed by Fe2V4O13 could be well described with a simple pseudo-first-order rate equation between the reaction temperatures of 15 degrees C and 30 degreesC. It was inferred from the reaction activation energy data that the generation of the hydroxyl radical was a control step in a series of reactions for the oxidation of Acid Orange II in the presence of H2O2 and Fe2V4O13. The catalytic activity of Fe2V4O13 towards degradation of Acid Orange II was not only much higher than that of alpha-Fe2O3, V2O5 and FeVO4 but also than that of their mixtures with an identical ratio of Fe and V, such as 2FeVO4 + V2O5 and Fe2O3 + 2V2O5. The high catalytic activity possibly involved a special two-way Fenton-like mechanism and the synergistic activation of Fe(III) and V(V) in Fe2V4O13 towards H2O2.
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Zhan F, Huang SS, Niu ZC, Ni HQ, Xiong YH, Fang ZD, Zhou HY, Luo Y. Desorption and ripening of low density InAs quantum dots. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:844-847. [PMID: 19441405 DOI: 10.1166/jnn.2009.c037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this paper, combining low deposition rate with proper growth temperature, we have developed a way to prepare very low-density quantum dots (QDs) suited for the study of single QD properties without resorting to submicron lithography. Experiment results demonstrate that InAs desorption is significant during growing the low density QDs. Ripening of InAs QDs is clearly observed during the post-growth annealing. Photoluminescence spectroscopy reveals that the emission wavelength of low density InAs QDs arrives at 1332.4 nm with a GaAs capping layer.
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Wu BP, Wu DH, Xiong YH, Huang SS, Ni HQ, Xu YQ, Niu ZC. Long-wavelength emission InAs quantum dots grown on InGaAs metamorphic buffers. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2009; 9:1333-1336. [PMID: 19441518 DOI: 10.1166/jnn.2009.c150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this work, InAs quantum dots (QDs) grown on a linear graded InGaAs metamorphic buffer layer by molecular beam epitaxy have been investigated. The growth of the metamorphic buffer layers was carefully optimized, yielding a smooth surface with a minimum root mean square of roughness of less than 0.98 nm as measured by atomic force microscopy (AFM). InAs QDs were then grown on the buffer layers, and their emission wavelength at room-temperature is 1.49 microm as measured by photoluminescence (PL). The effects of post-growth rapid thermal annealing (RTA) on the optical properties of the InAs QDs were investigated. After the RTA, the PL peak of the QDs was blue-shifted and the full width at half maximum decreased.
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Huang JS, Huang SS. Role of growth factors in oncogenesis: growth factor-proto-oncogene pathways of mitogenesis. CIBA FOUNDATION SYMPOSIUM 2008; 116:46-65. [PMID: 3000708 DOI: 10.1002/9780470720974.ch4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Cellular genes which encode proteins involved in the response of cells to stimulation by growth factors may be potential oncogenes. The factors involved in the signal transmission from growth factor-receptor interaction to DNA synthesis constitute a cascade system which we call the 'growth factor-proto-oncogene pathway(s) of mitogenesis'. For each growth factor, all the responsive cells, regardless of cell types and tissue source, have specific growth factor receptors which are similar, if not identical, in molecular weight and biological activity. Thus, we believe that the growth factor-proto-oncogene pathway(s) functions in the same manner in all responsive cells. Platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and brain-derived growth factor (BDGF) are major growth factors for connective tissue cells and do not share a common pathway in mitogenesis in responsive cells. The gene product of c-myc may be involved in the cellular response of cells stimulated by PDGF or FGF, but not directly in the signal transmission which leads to DNA synthesis.
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Huang SS, Liao QL, Hua M, Wu XM, Bi KS, Yan CY, Chen B, Zhang XY. Survey of heavy metal pollution and assessment of agricultural soil in Yangzhong district, Jiangsu Province, China. CHEMOSPHERE 2007; 67:2148-55. [PMID: 17275882 DOI: 10.1016/j.chemosphere.2006.12.043] [Citation(s) in RCA: 208] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 11/10/2006] [Accepted: 12/11/2006] [Indexed: 05/13/2023]
Abstract
We investigated concentrations of Hg, Cd, Pb, Zn, Cu, As, Ni, and Cr in samples of soil, cereal, and vegetables from Yangzhong district, China. Compared to subsoils, the sampled topsoils are enriched in Hg, Cd, Cu, Pb, Zn, and As. High levels of Cd and Hg are observed in most agricultural soils. Concentrations of Cr and Ni show little spatial variation, and high Cu, Pb, and Zn contents correspond well to areas of urban development. High As contents are primarily recorded at the two ends of the sampled alluvion. The contents of Cd, Hg, and total organic carbon (TOC) increase gradually to maximum values in the upper parts of soil profiles, while Cr and Ni occur in low concentrations within sampled profiles. As, Pb, Cu, and Zn show patterns of slight enrichment within the surface layer. Compared to data obtained in 1990, Cd and Hg show increased concentrations in 2005; this is attributed to the long-term use of agrochemicals. Cr and Ni contents remained steady over this interval because they are derived from the weathering of parent material and subsequent pedogenesis. The measured As, Cu, Pb, and Zn contents show slight increases over time due to atmospheric deposition of material sourced from urban anthropogenic activity. Low concentrations of heavy metals are recorded in vegetables and cereals because the subalkaline environment of the soil limits their mobility. Although the heavy metal concentrations measured in this study do not pose a serious health risk, they do affect the quality of agricultural products.
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Ke L, Yu P, Zhang ZX, Huang SS, Huang G, Ma XH. Congou tea drinking and oesophageal cancer in South China. Br J Cancer 2002; 86:346-7. [PMID: 11875696 PMCID: PMC2375216 DOI: 10.1038/sj.bjc.6600054] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2001] [Revised: 10/15/2001] [Accepted: 11/02/2001] [Indexed: 02/05/2023] Open
Abstract
The study from a large hospital-based case-control for 1248 cases with oesophageal cancer and the same number of controls in South China showed that Congou, a grade of Chinese black tea, may protect against cancers of the oesophagus and reduce the risk of a combination of alcohol drinking and smoking (especially smoking), regardless of temperature when drinking.
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Liu Q, Ling TY, Shieh HS, Johnson FE, Huang JS, Huang SS. Identification of the high affinity binding site in transforming growth factor-beta involved in complex formation with alpha 2-macroglobulin. Implications regarding the molecular mechanisms of complex formation between alpha 2-macroglobulin and growth factors, cytokines, and hormones. J Biol Chem 2001; 276:46212-8. [PMID: 11583997 DOI: 10.1074/jbc.m105177200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The biological activities of transforming growth factor-beta isoforms (TGF-beta(1,2)) are known to be modulated by alpha(2)-macroglobulin (alpha(2)M). alpha(2)M forms complexes with numerous growth factors, cytokines, and hormones, including TGF-beta. Identification of the binding sites in TGF-beta isoforms responsible for high affinity interaction with alpha(2)M many unravel the molecular basis of the complex formation. Here we demonstrate that among nine synthetic pentacosapeptides with overlapping amino acid sequences spanning the entire TGF-beta(1) molecule, the peptide (residues 41-65) containing Trp-52 exhibited the most potent activity in inhibiting the formation of complexes between (125)I-TGF-beta(1) and activated alpha(2)M (alpha(2)M*) as determined by nondenaturing polyacrylamide gel electrophoresis and by plasma clearance in mice. TGF-beta(2) peptide containing the homologous sequence and Trp-52 was as active as the TGF-beta(1) peptide, whereas the corresponding TGF-beta(3) peptide lacking Trp-52, was inactive. The replacement of the Trp-52 with alanine abolished the inhibitory activities of these peptides. (125)I-TGF-beta(3), which lacks Trp-52, bound to alpha(2)M* with an affinity lower than that of (125)I-TGF-beta(1). Furthermore, unlabeled TGF-beta(3) and the mutant TGF-beta(1)W52A, in which Trp-52 was replaced with alanine, were less potent than unlabeled TGF-beta(1) in blocking I(125)-TGF-beta(1) binding to alpha(2)M*. TGF-beta(1) and TGF-beta(2) peptides containing Trp-52 were also effective in inhibiting I(125)-nerve growth factor binding to alpha(2)M*. Tauhese results suggest that Trp-52 is involved in high affinity binding of TGF-beta to alpha(2)M*. They also imply that TGF-beta and other growth factors/cytokines/hormones may form complexes with alpha(2)M* via a common mechanism involving the interactions between topologically exposed Trp and/or other hydrophobic residues and a hydrophobic region in alpha(2)M*.
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Chen XL, Huang SS, Yao YX, Li WB, Wang XL, Zhou AM. Promotion of pulmonary fibroblast proliferation and apoptosis by sodium nitroprusside. SHENG LI XUE BAO : [ACTA PHYSIOLOGICA SINICA] 2001; 53:483-9. [PMID: 11930231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The effects of nitric oxide (NO) donor sodium nitroprusside (SNP) on the proliferation and apoptosis and on Bcl-2, Bax and p53 proteins of pulmonary fibroblasts were investigated by using MTT cleavage assay, agarose gel electrophoresis and flow cytometric analysis. The results showed increases in the optical density (550 nm) of MTT cleavage assay, the number of cells and the proliferation index (PI), in comparison with the control. The number of apoptotic cells was also increased, though the percentage of apoptotic cells was too low to reveal oligonucleosomal fragmentation of characteristic ladder pattern, which is associated with apoptosis. In the meantime, the level of Bcl-2 decreased and that of Bax increased, while the p53 remained unchanged. These results suggest that exogenous NO has a dual effect on proliferation and apoptosis; and the action of NO on pulmonary fibroblasts is mainly proliferative. Down regulation of Bcl-2 and up regulation of Bax are implicated in the molecular mechanisms of this action.
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Gibney BR, Huang SS, Skalicky JJ, Fuentes EJ, Wand AJ, Dutton PL. Hydrophobic modulation of heme properties in heme protein maquettes. Biochemistry 2001; 40:10550-61. [PMID: 11523997 DOI: 10.1021/bi002806h] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have investigated the properties of the two hemes bound to histidine in the H10 positions of the uniquely structured apo form of the heme binding four-helix bundle protein maquette [H10H24-L6I,L13F](2), here called [I(6)F(13)H(24)](2) for the amino acids at positions 6 (I), 13 (F) and 24 (H), respectively. The primary structure of each alpha-helix, alpha-SH, in [I(6)F(13)H(24)](2) is Ac-CGGGEI(6)WKL.H(10)EEF(13)LKK.FEELLKL.H(24)EERLKK.L-CONH(2). In our nomenclature, [I(6)F(13)H(24)] represents the disulfide-bridged di-alpha-helical homodimer of this sequence, i.e., (alpha-SS-alpha), and [I(6)F(13)H(24)](2) represents the dimeric four helix bundle composed of two di-alpha-helical subunits, i.e., (alpha-SS-alpha)(2). We replaced the histidines at positions H24 in [I(6)F(13)H(24)](2) with hydrophobic amino acids incompetent for heme ligation. These maquette variants, [I(6)F(13)I(24)](2), [I(6)F(13)A(24)](2), and [I(6)F(13)F(24)](2), are distinguished from the tetraheme binding parent peptide, [I(6)F(13)H(24)](2), by a reduction in the heme:four-helix bundle stoichiometry from 4:1 to 2:1. Iterative redesign has identified phenylalanine as the optimal amino acid replacement for H24 in the context of apo state conformational specificity. Furthermore, the novel second generation diheme [I(6)F(13)F(24)](2) maquette was related to the first generation diheme [H10A24](2) prototype, [L(6)L(13)A(24)](2) in the present nomenclature, via a sequential path in sequence space to evaluate the effects of conservative hydrophobic amino acid changes on heme properties. Each of the disulfide-linked dipeptides studied was highly helical (>77% as determined from circular dichroism spectroscopy), self-associates in solution to form a dimer (as determined by size exclusion chromatography), is thermodynamically stable (-DeltaG(H)2(O) >18 kcal/mol), and possesses conformational specificity that NMR data indicate can vary from multistructured to single structured. Each peptide binds one heme with a dissociation constant, K(d1) value, tighter than 65 nM forming a series of monoheme maquettes. Addition of a second equivalent of heme results in heme binding with a K(d2) in the range of 35-800 nM forming the diheme maquette state. Single conservative amino acid changes between peptide sequences are responsible for up to 10-fold changes in K(d) values. The equilibrium reduction midpoint potential (E(m7.5)) determined in the monoheme state ranges from -156 to -210 mV vs SHE and in the diheme state ranges from -144 to -288 mV. An observed heme-heme electrostatic interaction (>70 mV) in the diheme state indicates a syn global topology of the di-alpha-helical monomers. The heme affinity and electrochemistry of the three H24 variants studied identify the tight binding sites (K(d1) and K(d2) values <200 nM) having the lower reduction midpoint potentials (E(m7.5) values of -155 and -260 mV) with the H10 bound hemes in the parent tetraheme state of [H10H24-L6I,L13F](2), here called [I(6)F(13)H(24)](2). The results of this study illustrate that conservative hydrophobic amino acid changes near the heme binding site can modulate the E(m) by up to +/-50 mV and the K(d) by an order of magnitude. Furthermore, the effects of multiple single amino acid changes on E(m) and K(d) do not appear to be additive.
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Liu GD, Liao JP, Huang SS, Shen GL, Yu RQ. Fluorescence spectral study of interaction of water-soluble metal complexes of Schiff-base and DNA. ANAL SCI 2001; 17:1031-6. [PMID: 11708054 DOI: 10.2116/analsci.17.1031] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The fluorescence spectral characteristics and the interaction of several water-soluble metal complexes of Schiff-base with DNA are described. Among the complexes tested, Mn-Schiff-base bound to DNA showed a marked decrease in the fluorescence intensity with a blue shift of the excitation and emission peaks. Some hypochromism in the UV absorption spectra was also observed. KI quenching and competitive binding to DNA between Mn-Schiff-base and ethidium bromide (EB) were studied in connection with other experimental observations to show that the interactive model between Mn-Schiff-base and DNA is an intercalative one. The pH and salt effect on the fluorescence properties was also investigated. The linear relationship between F/F0 and the concentration of calf thymus DNA covers 3.0 x 10(-6)-2 x 10(-4) mol L-1, which can be utilized for determining traces of calf thymus DNA with a detection limit of 8.0 x 10(-7) mol L-1 in base pairs.
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Lau CP, Tse HF, Yu CM, Teo WS, Kam R, Ng KS, Huang SS, Lin JL, Fitts SM, Hettrick DA, Hill MR. Dual-site atrial pacing for atrial fibrillation in patients without bradycardia. Am J Cardiol 2001; 88:371-5. [PMID: 11545756 DOI: 10.1016/s0002-9149(01)01681-2] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Atrial pacing has been shown to delay the onset of atrial fibrillation (AF) when compared with ventricular pacing in patients with sick sinus syndrome. The role for pacing in the control of AF in patients without bradycardia is uncertain. We performed a randomized, crossover, single-blinded study in 22 patients (14 women, aged 63 +/- 10 years) with paroxysmal AF refractory to treatment with oral sotalol (202 +/- 68 mg/day) and no bradycardic indication for pacing. All patients received a dual-chamber pacemaker with 2 atrial pacing leads positioned at the high right atrium and coronary sinus ostium, respectively. Patients were randomized in a crossover fashion to be paced for 12 weeks, either with high right atrial (RA) pacing at 30 beats/min ("Off") or dual-site RA pacing with an overdrive algorithm that maintained atrial pacing at a rate slightly above the sinus rate ("On"). Treatment on resulted in a significantly higher percentage of atrial pacing and a reduction in atrial ectopic frequency than the treatment off period. The time to the first clinical AF recurrence was prolonged (15 +/- 17 to 50 +/- 35 days, p = 0.006), and total AF burden was reduced (45 +/- 34% vs 22 +/- 29%, p = 0.04) in the on-treatment phase. However, there was no difference in AF checklist symptom scores or overall quality-of-life measures. Dual-site RA pacing with continued sinus overdrive prolonged the time to AF recurrence and decreased AF burden in patients with paroxysmal AF. The absence of a major impact on symptom control suggests that pacing should be used as an adjunctive therapy with other treatment modalities for AF.
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Liu GD, Zhong TS, Huang SS, Shen GL, Yu RQ. Renewable amperometric immunosensor for complement 3 assay based on the sol-gel technique. FRESENIUS' JOURNAL OF ANALYTICAL CHEMISTRY 2001; 370:1029-34. [PMID: 11583082 DOI: 10.1007/s002160100890] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
A renewable amperometric immunosensor based on the sol-gel technique has been constructed by dispersing graphite, complement 3 (C3) antiserum, and sol-gel at low temperature. The prepared immunosensor is rigid, porous, and has a renewable external surface. A competitive binding assay has been used to determine C3 in human serum with the aid of C3 labeled with horseradish peroxidase. The enzyme-labeled antigen can readily diffuse toward the encapsulated antibody, which retains its binding properties. The experimental conditions for the assay with the biocomposite, including the loading of C3 antiserum in the biocomposite, the amount of labeled C3 in incubation solution, incubation time, and temperature, have been optimized. Using C3 labeled with horseradish peroxidase, and o-AP as the substrate, amperometric detection at -150 mV (relative to the SCE) results in a linear detection range of 1.17-35.1 microg mL(-1), with a detection limit of 0.56 microg mL(-1). Serum samples have been assayed and the results demonstrate the feasibility of the proposed immunosensor for clinical analysis. The surface of the immunosensor can be renewed simply by polishing to obtain a fresh immunocomposite ready to use in a new competitive assay.
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Chen XL, Huang SS, Li WB, Wang DH, Wang XL. Inhibitory effect of aminoguanidine on bleomycin-induced pulmonary toxicity in rat. Acta Pharmacol Sin 2001; 22:711-5. [PMID: 11749843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
AIM To observe the inhibitory effect of aminoguanidine (AG) on the pulmonary toxicity induced by bleomycin A5 (BLM-A5) in rat. METHODS The contents of hydroxyproline, nitrite/nitrate (NO2-/NO3-), and malondialdehyde (MDA), which reflect fibrosis, nitric oxide (NO) production, and hyperoxidative injury of lung, were investigated by colorimetry. Histologic and morphometric examination of lung was also carried out on histological sections stained with hematoxylin and eosin (HE). RESULTS (1) The content of hydroxyproline in lung and MDA in out-going pulmonary blood (OPB) increased from 14 d to 30 d after intratracheal administration of BLM-A5. Collapsed alveoli and fibrotic areas were seen and a lot of fibroblasts appeared in the lung interstitum of the rats 30 d after BLM-A5. (2) The NO2-/NO3- content increased in supernatant of alveolar macrophage culture and in OPB. (3) The increment of hydroxyproline in lung and MDA in OPB induced by BLM-A5 was alleviated by aminoguanidine (AG, 20 mg.kg-1 . d-1, ip). AG also reduced the histologic and morphometric changes in lung interstitum. (4) The augment of NO2-/NO3- in OPB was blocked by AG. CONCLUSION AG had inhibitory effect on pulmonary injury and fibrosis induced by BLM-A5, and the inhibitory effect was related to the decrease of NO production in lung.
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Huang SS, Tsai MC, Chih CL, Hung LM, Tsai SK. Resveratrol reduction of infarct size in Long-Evans rats subjected to focal cerebral ischemia. Life Sci 2001; 69:1057-65. [PMID: 11508648 DOI: 10.1016/s0024-3205(01)01195-x] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Resveratrol is found in a wide variety of plant species. It is present in the seeds and skin of grapes and constitutes one of the major components of red wine. This study was undertaken to evaluate whether resveratrol could effectively suppress infarct size from the damaging effects of focal cerebral ischemia. The middle cerebral artery was occluded for 1 hr and 24 hr reperfusion in anesthetized Long-Evans rats. In pretreatment or treatment groups, resveratrol, at dosages of 10(-6), 10(-7), 10(-8) and 10(-9) g/kg, was intravenous injected 15 minutes before middle cerebral artery (MCA) occlusion or when the common carotid arteries clips were removed respectively. Pretreatment or treatment of resveratrol (10(-6), 10(-7), 10(-8) and 10(-9) g/kg) did not produce any changes in pH, blood gases, heart rate or mean arterial blood pressure, but it significantly reduced the total volume of infarction at the doses 10(-6) and 10(-7) g/kg. Our study suggests resveratrol is a potent neuroprotective agent in focal cerebral ischemia. Its beneficial effects may be related to its anti-platelet aggregation activity, vasodilating effect, antioxidant property or by all mechanisms together.
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Huang SS, Tsai SK, Chih CL, Chiang LY, Hsieh HM, Teng CM, Tsai MC. Neuroprotective effect of hexasulfobutylated C60 on rats subjected to focal cerebral ischemia. Free Radic Biol Med 2001; 30:643-9. [PMID: 11295362 DOI: 10.1016/s0891-5849(00)00505-0] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The effects of hexasulfobutylated C60 (FC4S), a free radical remover, on the total volume infarct size elicited by the damaging effects of focal cerebral ischemia were studied on Long-Evans rats in vivo. FC4S was administered intravenously either 15 min before middle cerebral artery (MCA) occlusion (pretreatment groups) or it was injected when the common carotid arteries clips were removed (treatment groups). FC4S did not alter the pH, blood gases, heart rate, or mean arterial blood pressure in either pretreatment or treatment groups of the rats. However, after administration of FC4S at dosages of 10 and 100 microg/kg, the total volume of infarction was significantly reduced in both pretreatment and treatment groups. In addition, after FC4S administration, the nitric oxide (NO) content in plasma was increased and the lactate dehydrogenase (LDH) levels was decreased. It is concluded that FC4S may be used as a neuroprotective agent on focal cerebral ischemia. The beneficial effects may be partly related to its antioxidant property and to the upregulation of NO production of the compound.
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Tsai MC, Chen YH, Huang SS. Amphetamine elicited potential changes in vertebrate and invertebrate central neurons. ACTA BIOLOGICA HUNGARICA 2001; 51:275-86. [PMID: 11034152] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The effects of amphetamine on potential changes in both vertebrate and invertebrate central neurons and factors affecting the potential changes were tested. The animals studied included mice, newborn rat and African snail. Seizure was elicited after lethal doses of d-amphetamine (75 mg/kg, i.p.) administration in mice. Repetitive firing of the action potentials were elicited after d-amphetamine (1-30 microM) administration in thin thalamic brain slices of newborn rat. Bursting firing of action potentials in the giant African central RP4 neuron were also elicited after d-amphetamine or l-amphetamine (0.27 mM) administration. The amphetamine elicited bursting firing of action potentials was not blocked even after high concentrations of d-tubocurarine, atropine, haloperidol, hexamethonium administration. Therefore, the amphetamine elicited potential changes may not be directly related to the activation of the receptors of the neuron. The bursting firing of action potentials elicited by amphetamine occurred 20-30 min after amphetamine administration extracellularly, even after high concentrations of d-amphetamine administration (0.27, 1 mM). However, the bursting firing of potentials occurred immediately if amphetamine was administrated intracellularly at lower concentration. Extracellular application of ruthenium red, the calcium antagonist, abolished the amphetamine elicited bursting firing of action potentials. If intracellular injection of EGTA, a calcium ion chelator, or injection with high concentrations of magnesium, the bursting firing of potentials were immediately abolished. These results suggested that the active site of amphetamine may be inside of the neuron and the calcium ion in the neuron played an important role on the bursting of potentials. In two-electrode voltage clamped RP4 neuron, amphetamine, at 0.27 mM, decreased the total inward and steady outward currents of the RP4 neuron. d-Amphetamine also decreased the calcium, Ia and the steady-state outward currents of the RP4 neuron. Besides, amphetamine elicited a negative slope resistance (NSR) if membrane potential was in the range of -50 to -10 mV. The NSR was decreased in cobalt substituted calcium free and sodium free solution. The effects of secondary messengers on the amphetamine elicited potential changes were tested. The bursting firing of action potentials elicited by amphetamine in central snail neurons decreased following extracellular application of H8 (N-(2-methyl-amino) ethyl-3-isoquinoline sulphonamide dihydrochloride), a specific protein kinase A inhibitor and anisomycin, a protein synthesis inhibitor. However, the bursting firing of action potentials were not affected after extracellular application of H7 (1,(5-isoquinolinesulphonyl)-2-methylpiperasine dihydrochloride), a specific protein kinase C (PKC) inhibitor, or intracellular application of GDPbetaS, a G protein inhibitor. The oscillation of membrane potential of the bursting activity was blocked after intracellular injection of 3'-deoxyadenosine, an adenylyl-cyclase inhibitor. These results suggested that the bursting firing of action potentials elicited by d-amphetamine in snail neuron may be associated with the cyclic AMP second messenger system; on the other hand, it may not be associated with the G protein and protein kinase C activity. It is concluded that amphetamine elicited potential changes in both vertebrate and invertebrate central neurons. The changes are closely related to the ionic currents and second messengers of the neurons.
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Chen YH, Chang CH, Liang GJ, Huang SS, Hsieh HM, Teng CM, Tsai MC. Burst firing of action potentials in central snail neurons elicited by d-amphetamine: effect of anticonvulsants. Comp Biochem Physiol C Toxicol Pharmacol 2000; 127:221-31. [PMID: 11083032 DOI: 10.1016/s0742-8413(00)00144-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The effect of anticonvulsants on the burst firing of action potentials in snail central neuron elicited by d-amphetamine was studied in the identified RP4 neuron of the African snail, Achatina fulica Ferussac. Oscillation of membrane potential and burst firing of action potentials were elicited by d-amphetamine in a concentration-dependent manner. Voltage clamped studies revealed that d-amphetamine elicited a negative slope resistance (NSR) in steady-state I-V curve between - 40 and - 10 mV. The burst firing of action potentials was alleviated following extracellular application of phenytoin, but was not affected after ethosuximide, carbamazepine, and valproic acid. The NSR elicited by d-amphetamine was blocked by phenytoin. However, the NSR was not altered if carbamazepine was added. These results suggest that of the four anticonvulsants tested, only phenytoin could alleviate the burst firing of action potentials elicited by d-amphetamine in snail neuron.
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