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Hu H, Zhang S, Zhu S. Influence of aspirin and cigarette smoke extract on the expression of cyclin D1 and effects of cell cycle in esophageal squamous cell carcinoma cell line. Dis Esophagus 2008; 22:310-6. [PMID: 19207549 DOI: 10.1111/j.1442-2050.2008.00899.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The relationship between smoking and esophageal squamous cell carcinoma (ESCC) has been confirmed by epidemiology. Cyclin D(1) plays a critical role in regulating the cell cycle; it is an important regulator of cell cycle and can function as a transcriptional co-regulator. The importance of cyclin D(1) makes it an attractive target for anticancer therapy. Human ESCC cell line EC109 was cultured with aspirin and cigarette smoke extract (CSE) at different concentrations for 48 h. Cell growth was tested with 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide reduction assay; cyclin D(1) mRNA level was detected by reverse transcription-polymerase chain reaction assays; protein level of cyclin D(1) was detected by Western blot; the cell cycle change was monitored by flow cytometry detection assays. CSE stimulated cell proliferation, increased the protein level of cyclin D(1) in a dose-dependent manner (P < 0.01), and decreased the proportion of G(0)/G(1) phase cell of cell cycle. However, aspirin can inhibit the cell growth and suppress the protein level of cyclin D(1) after CSE affected the EC109 cell line in a dose-dependent manner (P < 0.01). Meanwhile, aspirin increased the proportion of G(0)/G(1) phase cell, while that of S and G(2)/M phases decreased. Aspirin can inhibit the cell growth and suppress the protein level of cyclin D(1) after CSE affected EC109 cell line. The probable mechanism is through decreasing the expression of cyclin D(1), thus stopping the transition of cell cycle from G(0)/G(1) to S phase.
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Huang HY, Daar ES, Sax PE, Young B, Cook P, Benson P, Cohen C, Scribner A, Hu H. The prevalence of transmitted antiretroviral drug resistance in treatment-naïve patients and factors influencing first-line treatment regimen selection. HIV Med 2008; 9:285-93. [PMID: 18400075 DOI: 10.1111/j.1468-1293.2008.00561.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVES To estimate the prevalence of transmitted antiretroviral (ARV) drug resistance, and to assess whether resistance testing influences first-line ARV regimen selection. METHODS Data on patients' characteristics were collected through questionnaires. ARV drug resistance was tested by genotypic methods and defined by Quest-Stanford classification rule. Physicians reported the intended and actual treatments and the factors considered in treatment selection. RESULTS Two hundred and twenty-eight patients were included. The prevalence of ARV drug resistance was 12.1%, with 9.8% for non-nucleoside reverse transcriptase inhibitors (NNRTIs), 4.5% for nucleoside reverse transcriptase inhibitors and 1.8% for protease inhibitors (PIs). Pill burdens, dosing frequency and physicians' experience with regimens were the major factors considered in treatment selection. The intended and actual treatment differed for 73 and 44% of the patients with and without ARV drug resistance, respectively [odds ratio (95% confidence interval, CI)=3.6 (1.5-9.0), P=0.006]. NNRTI-based regimens were intended for 10 patients with resistance to NNRTIs; these patients were prescribed PI-based regimens after genotypic testing. CONCLUSIONS Transmitted ARV drug resistance was detected in 12.1% of treatment-naïve patients, with resistance to NNRTIs the most common. Resistance-testing results played a partial role in first-line treatment selection. However, resistance to NNRTIs pre-empted NNRTI use.
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428
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Huang SP, Cheng WD, Hu JM, Xie Z, Hu H, Zhang H. A periodic density functional theory study on the effects of halides encapsulated in SiC nanotubes. J Chem Phys 2008; 129:174108. [DOI: 10.1063/1.3006425] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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429
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Crittenden M, Gough M, Seung S, Pang P, Thomas C, Hu H. Development of a Preclinical Model to Test Adjuvant Immunotherapy in Combination with SBRT. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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430
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Hu H, Lee HJ, Jiang C, Zhang J, Wang L, Zhao Y, Xiang Q, Lee EO, Kim SH, Lu J. Penta-1,2,3,4,6-O-galloyl- -D-glucose induces p53 and inhibits STAT3 in prostate cancer cells in vitro and suppresses prostate xenograft tumor growth in vivo. Mol Cancer Ther 2008; 7:2681-91. [DOI: 10.1158/1535-7163.mct-08-0456] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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431
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Widrick JJ, Maddalozzo GF, Hu H, Herron JC, Iwaniec UT, Turner RT. Detrimental effects of reloading recovery on force, shortening velocity, and power of soleus muscles from hindlimb-unloaded rats. Am J Physiol Regul Integr Comp Physiol 2008; 295:R1585-92. [PMID: 18753267 DOI: 10.1152/ajpregu.00045.2008] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
To better understand how atrophied muscles recover from prolonged nonweight-bearing, we studied soleus muscles (in vitro at optimal length) from female rats subjected to normal weight bearing (WB), 15 days of hindlimb unloading (HU), or 15 days HU followed by 9 days of weight bearing reloading (HU-R). HU reduced peak tetanic force (P(o)), increased maximal shortening velocity (V(max)), and lowered peak power/muscle volume. Nine days of reloading failed to improve P(o), while depressing V(max) and intrinsic power below WB levels. These functional changes appeared intracellular in origin as HU-induced reductions in soleus mass, fiber cross-sectional area, and physiological cross-sectional area were partially or completely restored by reloading. We calculated that HU-induced reductions in soleus fiber length were of sufficient magnitude to overextend sarcomeres onto the descending limb of their length-tension relationship upon the resumption of WB activity. In conclusion, the force, shortening velocity, and power deficits observed after 9 days of reloading are consistent with contraction-induced damage to the soleus. HU-induced reductions in fiber length indicate that sarcomere hyperextension upon the resumption of weight-bearing activity may be an important mechanism underlying this response.
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432
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Hu H, Shi Y, Chen Q, Yang W, Zhou H, Chen L, Tang Y, Zheng Y. Endogenous hydrogen sulfide is involved in regulation of respiration in medullary slice of neonatal rats. Neuroscience 2008; 156:1074-82. [PMID: 18793700 DOI: 10.1016/j.neuroscience.2008.08.025] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2008] [Revised: 07/25/2008] [Accepted: 08/11/2008] [Indexed: 10/21/2022]
Abstract
The purpose of the present study was to verify our assumption that rhythmic respiratory activity may be regulated by endogenous hydrogen sulfide (H(2)S) in the medullary slices of neonatal rats. We found that a moderate concentration of donor of H(2)S, NaHS, mainly induced diphasic respiratory responses indicated by changes of discharge frequency (DF) of hypoglossal rootlets, an initial inhibitory stage followed by a later excitatory one. Cystathionine beta-synthase (CBS) substrate, cysteine (CYS), exerted similar effects. CBS inhibitor, NH(2)OH, could eliminate both inhibitory and excitatory effects in the two stages induced by CYS. K(ATP) channel blocker, glibenclamide (Gl), could eliminate the decrease in DF in the initial stage, but not the increase in the later one. On the other hand, adenyl cyclase (AC) inhibitor, SQ-22536 (SQ) could eliminate the increase in DF in the later stage, but not the decrease in the initial one, of the rootlets caused by NaHS. Co-application of Gl and SQ eliminated both inhibitory and excitatory effect induced by NaHS. The cAMP level was increased in the later stage but not in the initial one by NaHS, and the increase in the cAMP level could be eliminated by SQ. It can be concluded that the endogenous H(2)S could be produced through the CBS-H(2)S pathway and could be involved in the control of the central rhythmic respiration in the in vitro medullary slices of neonatal rats by opening K(ATP) channels and activating AC-cAMP pathway of the neurons.
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Chibana K, Trudeau JB, Mustovitch AT, Hu H, Zhao J, Balzar S, Chu HW, Wenzel SE. IL-13 induced increases in nitrite levels are primarily driven by increases in inducible nitric oxide synthase as compared with effects on arginases in human primary bronchial epithelial cells. Clin Exp Allergy 2008. [DOI: 10.1111/j.1365-2222.2008.03071.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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434
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Zhang J, Zhang YW, Chen ZW, Zhou XY, Lu S, Luo QQ, Hu H, Miao LS, Ma LF, Xiang JQ. Adjuvant chemotherapy of cisplatin, 5-fluorouracil and leucovorin for complete resectable esophageal cancer: a case-matched cohort study in east China. Dis Esophagus 2008; 21:207-13. [PMID: 18430100 DOI: 10.1111/j.1442-2050.2007.00748.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
It is still controversial whether adjuvant chemotherapy of cisplatin, 5-fluorouracil and leucovorin can increase the overall survival of esophageal cancer patients, and which subgroup of patients get most benefits from it. Between 1998 and 2004, 66 esophageal cancer patients with adjuvant chemotherapy and 160 well-matched patients without chemotherapy were included in this study. Nine markers were measured in the protein level to analyze prognostic significance. In the whole group, adjuvant chemotherapy did not improve the survival of esophageal cancer patients. There was also no significant difference for survival in stage I (P=0.59 and P=0.59), stage II (P=0.28 and P=0.28) and stage III patients (P=0.144 and P=0.06) between the observation and the chemotherapy group. Chemotherapy was most effective for the patients who had metastases in cervical and/or celiac lymph nodes (IV subgroup). One and 3-year disease-free survival and overall survival were significantly better than for those who did not receive the chemotherapy(P=0.038, and 0.016, respectively). Bcl-2 expression was a bad prognostic factor, and was more predictive in the adjuvant chemotherapy group than in the no-chemotherapy group. Adjuvant chemotherapy significantly improved the treatment result of stage IV patients compared with the observation group. Bcl-2 could be used to analyze prognosis and guide the adjuvant treatment.
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435
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Liu S, Zhou X, Xiong Y, Yang Y, Wang C, Qu X, Xie Y, Hu H, Pang Z. APOLIPOPROTEIN E POLYMORPHISM AND CORONARY HEART DISEASE AND TYPE 2 DIABETESND TYPE 2 DIABETES. ATHEROSCLEROSIS SUPP 2008. [DOI: 10.1016/s1567-5688(08)70423-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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436
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Chibana K, Trudeau JB, Mustovich AT, Mustovitch AT, Hu H, Zhao J, Balzar S, Chu HW, Wenzel SE. IL-13 induced increases in nitrite levels are primarily driven by increases in inducible nitric oxide synthase as compared with effects on arginases in human primary bronchial epithelial cells. Clin Exp Allergy 2008; 38:936-46. [PMID: 18384429 DOI: 10.1111/j.1365-2222.2008.02969.x] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND Exhaled nitric oxide is increased in asthma, but the mechanisms controlling its production, including the effects of T-helper type 2 (Th2) cytokines, are poorly understood. In mouse and submerged human epithelial cells, Th2 cytokines inhibit expression of inducible nitric oxide synthase (iNOS). Arginases have been proposed to contribute to asthma pathogenesis by limiting the arginine substrate available to NOS enzymes, but expression of any of these enzymes has not been extensively studied in primary human cells. OBJECTIVES We hypothesized that primary human airway epithelial cells in air-liquid interface (ALI) culture would increase iNOS expression and activity in response to IL-13, while decreasing arginase expression. METHODS iNOS and arginase mRNA (real-time PCR) and protein expression (Western blot and immunofluorescence) as well as iNOS activity (nitrite levels) were measured in ALI epithelial cells cultured from bronchial brushings of normal and asthmatic subjects following IL-13 stimulation. RESULTS IL-13 up-regulated iNOS mRNA primarily at a transcriptional level in epithelial cells. iNOS protein and activity also increased, arginase1 protein expression decreased while arginase 2 expression did not change. The changes in iNOS protein correlated strongly with changes in nitrites, and inclusion of arginase (1 or 2) did not substantially change the relationship. Interestingly, iNOS mRNA and protein were not correlated. CONCLUSIONS These results contrast with many previous results to confirm that Th2 stimuli enhance iNOS expression and activity. While arginase 1 protein decreases in response to IL-13, neither arginase appears to substantially impact nitrite levels in this system.
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438
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Clauwaert P, Tolêdo R, van der Ha D, Crab R, Verstraete W, Hu H, Udert KM, Rabaey K. Combining biocatalyzed electrolysis with anaerobic digestion. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2008; 57:575-579. [PMID: 18359998 DOI: 10.2166/wst.2008.084] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Biocatalyzed electrolysis is a microbial fuel cell based technology for the generation of hydrogen gas and other reduced products out of electron donors. Examples of electron donors are acetate and wastewater. An external power supply can support the process and therefore circumvent thermodynamical constraints that normally render the generation of compounds such as hydrogen unlikely. We have investigated the possibility of biocatalyzed electrolysis for the generation of methane. The cathodically produced hydrogen could be converted into methane at a ratio of 0.41 mole methane mole(-1) acetate, at temperatures of 22+/-2 degrees C. The anodic oxidation of acetate was not hampered by ammonium concentrations up to 5 g N L(-1). An overview is given of potential applications for biocatalyzed electrolysis.
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439
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Xu Z, Gu Q, Hu H, Li F. A novel electrospun polysulfone fiber membrane: application to advanced treatment of secondary bio-treatment sewage. ENVIRONMENTAL TECHNOLOGY 2008; 29:13-21. [PMID: 18610541 DOI: 10.1080/09593330802008412] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Electrospun nanofibers and fine fibers have been used to remove submicron particles in air filtration. In this paper, direct-and polyaluminium chloride (PAC) pre-coagulation filtration of secondary bio-treatment sewage was studied using electrospun polysulfone fiber membrane (EPSFM). According to the results obtained, for direct filtration, suspended solids (SS), chemical oxygen demand (COD(Cr)) and NH3-N decreased 86.7, 71.2, 91.7% respectively, in filtrate of secondary bio-treatment sewage, while for PAC pre-coagulation filtration, the removal rate of SS, COD(Cr) and NH3-N reached 91.3, 85.3, 93.3 % respectively. EPSFM had a high efficiency in removing NH3-N, COD(Cr) and SS, especially for micron and submicron particles. EPSFM can reduce the content of some toxic metals, such as Cu, Zn and Ti, through interception and adsorption mechanism and can also remove dissolved organic matter such as humics and proteins through interception mechanism. EPSFM can remove some of volatile organic chemicals (VOCs) by adsorption and filtration, the removal rate of VOCs was in the range of 59-100 %. The number of VOCs in secondary bio-treatment sewage and its filtrate from direct filtration were 27 and 18 respectively, the major VOCs were benzene-, cyclohexane-, adamantine- and hydrocarbon derivates.
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440
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O'Lynnger T, He Y, Hu H, Hua Y, Muraszko KM, Xi G. Concomitant intracerebral infusion of tissue plasminogen activator and thrombin leads to brain injury. ACTA NEUROCHIRURGICA. SUPPLEMENT 2008; 105:55-58. [PMID: 19066083 DOI: 10.1007/978-3-211-09469-3_12] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Low doses of thrombin are neuroprotective while high doses are neurotoxic and lead to brain injury. However, evidence suggests that low doses of thrombin cause brain injury when infused concomitantly with tissue plasminogen activator (tPA), which is used clinically to facilitate evacuation of intracerebral hematomas. In this study, we examined the effects of intracerebral infusion of tPA and thrombin, individually and in combination. Rats were infused in the right basal ganglia with 50 microL saline solutions containing thrombin, tPA, or thrombin + tPA. In the first experiment, rats were used for blood-brain barrier (BBB) permeability measurements at 24 h after infusion. In the second experiment, animals were euthanized 3 days after infusion, and brain sections were stained with Fluoro-Jade to measure neuronal cell death. Behavioral tests were carried out before and after surgery. Infusion of thrombin + tPA markedly increased Evans blue tissue content in ipsilateral brain samples (p < 0.05). Fluoro-Jade-stained sections from thrombin + tPA group demonstrated significantly higher cell death counts (p < 0.01). Significant neurological deficit was revealed in thrombin + tPA group in forelimb-placing and corner-turn tests (p < 0.01). This study shows that tPA potentiates the neurotoxic effects of thrombin and leads to increased BBB permeability, neuronal cell death, and neurological deficit. Our results suggest that using tPA to lyse intracerebral hematomas has potential to produce neuronal cell death and disruption of BBB.
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441
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Reungjui S, Hu H, Mu W, Roncal CA, Croker BP, Patel JM, Nakagawa T, Srinivas T, Byer K, Simoni J, Wesson D, Sitprija V, Johnson RJ. Thiazide-induced subtle renal injury not observed in states of equivalent hypokalemia. Kidney Int 2007; 72:1483-92. [PMID: 17928827 DOI: 10.1038/sj.ki.5002564] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Hydrochlorothiazide (HCTZ) is used to manage hypertension and heart failure; however, its side effects include mild hypokalemia, metabolic abnormalities, and volume depletion, which might have deleterious effects on renal and endothelial function. We studied whether HCTZ cause renal injury and/or altered vasoreactivity and if these changes are hypokalemia-dependent. Rats were given a normal diet or a diet moderately low in potassium K+ with or without HCTZ. Animals fed either a low K+ diet alone or HCTZ developed mild hypokalemia. There was no significant difference in systolic blood pressure in the different treatment groups. All three groups with hypokalemia had mild proteinuria; low K(+)-HCTZ rats had reduced creatinine clearance. HCTZ-treated rats displayed hypomagnesemia, hypertriglyceridemia, hyperglycemia, insulin resistance, and hyperaldosteronism. No renal injury was observed in the groups without HCTZ; however, increased kidney weight, glomerular ischemia, medullary injury, and cortical oxidative stress were seen with HCTZ treatment. Endothelium-dependent vasorelaxation was reduced in all hypokalemic groups and correlated with reduced serum K+, serum, and urine nitric oxide. Our results show that HCTZ is associated with greater renal injury for the same degree of hypokalemia as the low K+ diet, suggesting that factors such as chronic ischemia and hyperaldosteronism due to volume depletion may be responsible agents. We also found impaired endothelium-dependent vasorelaxation was linked to mild hypokalemia.
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442
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Zanoteli E, Campos Y, Vergani N, Qiu X, Oberoi K, Hu H, Mann L, d’Azzo A. G.P.19.10 Ozz-E3 ligase expression during muscle regeneration. Neuromuscul Disord 2007. [DOI: 10.1016/j.nmd.2007.06.450] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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443
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Li Y, Lu L, Ding A, Hu H, Zeng Q, Zheng S, Wu Y. Benchmarking of MCAM 4.0 with the ITER 3D model. FUSION ENGINEERING AND DESIGN 2007. [DOI: 10.1016/j.fusengdes.2007.02.022] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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444
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Hu H, Lu D, Liu Y. Effect of supplementary feeding on growth
performance and ruminal fermentation in winter
season grazing sheep. JOURNAL OF ANIMAL AND FEED SCIENCES 2007. [DOI: 10.22358/jafs/74582/2007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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445
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Hu H, de Haan G. Trained Bilateral Filters and Applications to Coding Artifacts Reduction. ACTA ACUST UNITED AC 2007. [DOI: 10.1109/icip.2007.4378957] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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446
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Roy A, Pallaniappan K, Hu H, Wright R, Balakrishnan K. Predictors of Blood Lead Among 3–7-Year-Old Children in Chennai, India. Epidemiology 2007. [DOI: 10.1097/01.ede.0000276873.24287.7f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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447
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Huang SP, Wu DS, Hu JM, Zhang H, Xie Z, Hu H, Cheng WD. First-principles study: size-dependent optical properties for semiconducting silicon carbide nanotubes. OPTICS EXPRESS 2007; 15:10947-10957. [PMID: 19547452 DOI: 10.1364/oe.15.010947] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Using first-principles calculations, we investigate the effect of tube size on optical properties of the zigzag, armchair, and chiral SiC nanotubes. The results indicate that the optical spectra of SiC nanotubes are dependent on the diameter and chirality, and that optical anisotropy is observed for different light polarizations. For a given chirality of SiCNTs, redshifts or blueshifts of the peaks in the dielectric function and energy loss function with increasing tube diameter are possible due to the competition between the size effect and pi orbitals overlapping, and the shifts become smaller as the tube diameter increases. The unusual optical properties of semiconducting SiC nanotubes present an opportunity for applications in electro-optical devices.
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Weisskopf MG, Weuve J, Jarrell J, Hu H, Tellez-Rojo MM, Hernandez-Avila M. Reply: Maternal lead exposure, secondary sex ratio and dose-exposure fallacy. Hum Reprod 2007. [DOI: 10.1093/humrep/dem194] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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449
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Wang B, Yu G, Hu H, Wang L. Quantitative structure-activity relationships and mixture toxicity of substituted benzaldehydes to Photobacterium phosphoreum. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2007; 78:503-9. [PMID: 17541483 DOI: 10.1007/s00128-007-9144-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Accepted: 03/16/2007] [Indexed: 05/15/2023]
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450
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Razmara M, Hu H, Masquelier M, Li N. Glycoprotein IIb/IIIa blockade inhibits platelet aminophospholipid exposure by potentiating translocase and attenuating scramblase activity. Cell Mol Life Sci 2007; 64:999-1008. [PMID: 17372676 PMCID: PMC11136311 DOI: 10.1007/s00018-007-6546-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The present study investigated the mechanisms underlying the inhibition of platelet phosphatidylserine (PS) exposure by GPIIb/IIIa blockade. Platelet PS exposure induced by thrombin stimulation was cell-cell contact dependent. GPIIb/IIIa blockade by c7E3 or SR121566 inhibited thrombin-induced platelet PS exposure. Thrombin stimulation induced mild, while A23187 induced extensive platelet-derived microparticle (PDMP) generation. Thrombin-induced PDMP generation was not inhibited by GPIIb/IIIa blockade. Aminophospholipid translocase activity was reduced upon platelet activation by thrombin. The reduction of non-PS-exposing platelets was attenuated by GPIIb/IIIa blockade, while little translocase activity was seen in PS-exposing platelets. Thrombin increased scramblase activity slightly in non-PS-exposing platelets, which was inhibited by GPIIb/IIIa blockade, and markedly enhanced scramblase activity in PS-exposing platelets. Activation of platelet calpain and caspase-3 or cytosolic calcium mobilization were not altered by GPIIb/IIIa inhibition. Thus, GPIIb/IIIa blockade inhibits platelet PS exposure by enhancing translocase activity and attenuating scramblase activity, but does not inhibit PDMP generation.
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