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Zhou R, Sun Q. Energetics of macroscopic helical domain in different tube geometries and loading. EPJ WEB OF CONFERENCES 2010. [DOI: 10.1051/epjconf/20100627003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Wang W, Shi G, He J, Zhou R. UP-2.128: The Value of Prostate-Specific Antigen Doubling Time for Patients with Prostate Cancer After Maximal Androgen Blockade. Urology 2009. [DOI: 10.1016/j.urology.2009.07.347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Zhou R, Liu Q, Todd NW, Deepak J, Liu Z, Stass SA, Edelman MJ, Katz RL, Jiang F. Evaluation of aldehyde dehydrogenase 1 (ALDH1) as a marker of non-small cell lung cancer (NSCLC) stem cells (SCs) and correlation with prognosis. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.11105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
11105 Background: ALDH1 is a cytosolic enzyme responsible for oxidizing intracellular aldehydes, and conversion of retinol to retinoic acid in SCs. ALDH1 has been previously demonstrated to be a marker for SCs in breast cancer (Ginestier C, et al., Cell Stem Cell. 2007 Nov; 1(5):555–67). The Aldefluor assay is based on conversion of a synthetic substrate BAAA, when passively infused into cytosol, to brightly fluorescent BAA by ALDH1. Combined with fluorescence-activated cell sorting (FACS), it has been used successfully in hematopoietic and breast cancer SCs isolation. ALDH1 is also found in NSCLC. We hypothesized that ALDH1 would be a marker for NSCLC SCs and a potential prognostic marker. Methods: NSCLC SCs were isolated from human NSCLC cell lines using the Aldefluor assay and FACS. ALDH1-positive cells were analyzed extensively for SC characteristics. ALDH1 expression in 303 NSCLC biopsy specimens from three independent cohorts of NSCLC patients was then analyzed by immunohistochemisty (IHC) using an ALDH1 antibody (Santa Cruz Biotechnology) and commercially available negative controls. Results: Isolated cancer cells with high ALDH1 activity displayed cancer SCs features, including capacities for proliferation, self-renewal, differentiation; resistance to chemotherapeutic agents including cisplatin, vinorelbine, gemcitabine and docetaxel; expression of the SC surface marker CD133, and high invasiveness. ALDH1-positive cells generated tumors in vivo recapitulating heterogeneity of parental cells. Xenograft tumors derived from ALDH1-positive cells (103 each) were 36±2.9 mm3 on average in size, with some of the cells having lost ALDH1 expression. Xenograft tumors derived from ALDH1-negative cells (105 each) were 4 mm3 on average in size, without ALDH1 reactivation. Statistical analysis of quantitative IHC and clinical data showed ALDH1 expression was correlated with higher stage and grade of NSCLC (p = 0.02). Expression of ALDH1 in stage I NSCLC patients was linked to decreased 5 year cancer-specific survival (62% vs. 96%, p = 0.006) and overall survival (32% vs. 72%, p = 0.009). Conclusions: 1. ALDH1 is a NSCLC SC-associated tumor marker. 2. ALDH1 expression is a negative prognostic marker in early stage NSCLC. No significant financial relationships to disclose.
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Brewster AM, Etzel C, Zhou R, Wong Y, Edge SB, Blayney DW, Wilson J, Hudis C, Weeks JC, Theriault RL. The impact of obesity on adherence to the National Comprehensive Cancer Network (NCCN) guidelines recommending chemotherapy for patients with operable breast cancer. J Clin Oncol 2009. [DOI: 10.1200/jco.2009.27.15_suppl.6517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
6517 Background: Obesity (measured using body mass index [BMI]) is regarded as a prognostic factor for worse breast cancer survival. We hypothesized that obesity may influence adherence to NCCN guidelines recommending chemotherapy for patients with operable breast cancer at NCCN centers. Methods: We identified women < 70 years diagnosed with stage I, II, or III breast cancer from 1997 to 2006 at 8 NCCN centers for whom guidelines recommended chemotherapy. Body mass index was assessed in categories (<25 kg/m2 [normal], 25 to <30 kg/m2 [overweight], 30 to 39kg/m2 [obese], ≥40 kg/m2 [morbidly obese]) and in 5 kg/m2 increments. Multivariable logistic regression analysis adjusting for center, age at diagnosis, ethnicity, comorbidity score, and guideline was used to examine the association between BMI at diagnosis and non-receipt of chemotherapy. Results: 9,389 women were eligible for the study: 38% normal weight; 30% overweight; 23% obese; 5% morbidly obese; and 4% unknown. In multivariable analysis with BMI as a categorical variable, there was no association between weight status and non-receipt of chemotherapy (p = 0.35). When BMI was assessed in 5kg/m2 increments, weight status was a statistically significant predictor of non-receipt of chemotherapy (p = 0.02), but the odd ratios exceeded 1.0 only for BMIs ≥42.6kg/m2. Other patient-related factors associated with non-receipt of chemotherapy included older age at diagnosis (p < 0.01), presence of comorbidities (p < 0.01) and center (p < 0.01). Conclusions: Overall, the quality of breast cancer care as measured by adherence to NCCN guidelines recommending chemotherapy was not affected by patient overweight or obese status. Chemotherapy use was lower among patients with extreme morbid obesity, which may represent appropriate clinical decision-making. Evaluating factors that may contribute to worse prognosis among obese patients is essential for individualizing care and improving breast cancer outcome. No significant financial relationships to disclose.
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Zhu L, Piao J, Xia Y, Cheng Y, Zhou R. The antioxidative ability of erythrocyte of children with different selenium status. ACTA PHARMACOLOGICA ET TOXICOLOGICA 2009; 59 Suppl 7:331-5. [PMID: 3022550 DOI: 10.1111/j.1600-0773.1986.tb02773.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Zhou L, Jones SCP, Angen Ø, Bossé JT, Nash JHE, Frey J, Zhou R, Chen HC, Kroll JS, Rycroft AN, Langford PR. PCR specific for Actinobacillus pleuropneumoniae serotype 3. Vet Rec 2008; 162:648-52. [PMID: 18487584 DOI: 10.1136/vr.162.20.648] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Serotypes 3 and 8 of Actinobacillus pleuropneumoniae, the aetiological agent of porcine pleuropneumonia, have been reported to predominate in the UK. Direct serotyping of isolates of the organism is typically determined by the immunological reactivity of rabbit serum to its surface polysaccharides, but the method has limitations, for example, cross-reactions between serotypes 3, 6 and 8. This study describes the development of a serotype 3-specific pcr, based on the capsule locus, which can be used in a multiplex format with the organism's specific gene apxIV. The pcr test was evaluated on 266 strains of A pleuropneumoniae and 121 strains of other organisms, including all the major respiratory bacterial pathogens of pigs. The test was highly specific and sensitive and should be useful for differentiating strains of serotypes 3, 6 and 8, and in seroprevalence and epidemiological surveys in regions where serotype 3 is prevalent, such as the UK.
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Zhou R, Skalli O. Identification of cadherin-11 down-regulation as a common response of astrocytoma cells to Transforming Growth Factor-α. Differentiation 2008. [DOI: 10.1111/j.1432-0436.2000.660402.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Yang G, Zhou R, Tang T, Shi S. Simple and Efficient Isolation of High-Quality Total RNA fromHibiscus tiliaceus, a Mangrove Associate and Its Relatives. Prep Biochem Biotechnol 2008; 38:257-64. [DOI: 10.1080/10826060802164991] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Wang JX, Tang W, Zhou R, Wan J, Shi LP, Zhang Y, Yang YF, Li Y, Zuo JP. The new water-soluble artemisinin derivative SM905 ameliorates collagen-induced arthritis by suppression of inflammatory and Th17 responses. Br J Pharmacol 2008; 153:1303-10. [PMID: 18264129 DOI: 10.1038/bjp.2008.11] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND AND PURPOSE Our previous study showed that SM905, a novel artemisinin derivative, exhibited potent immunosuppressive activity. In this study, we evaluate preventive and therapeutic effect of SM905 on collagen-induced arthritis (CIA) in DBA/1 mice, and investigate its mechanisms both in inflammatory and autoimmune aspects of the disease. EXPERIMENTAL APPROACH CIA was induced by type II bovine collagen (CII) in DBA/1 mice. SM905 was given orally either before (continuously 1 day before booster immunization) or after disease onset (continuously 14 days after booster immunization). Disease incidence and severity were monitored, mRNA expression of proinflammatory mediators was determined by real-time PCR, purified T cell proliferation was assessed using [(3)H]-thymidine incorporated assay, and T helper (Th) 17/Th1/Th2 type cytokine production was examined by ELISA. KEY RESULTS Oral treatment with SM905 delayed disease onset, reduced arthritis incidence and severity, and suppressed the enhanced expression of pro-inflammatory cytokines, chemokines and chemokine receptors in draining lymph nodes. The CII-induced T cell proliferation and production of interleukin (IL)-17A by T cells were strikingly inhibited. Correspondingly, the mRNA expression of IL-17A and RORgamma t (a specific transcription factor for Th17) was also reduced. This effect was coupled with a striking reduction of IL-6 production, which has a critical role in Th17 development. In established arthritis, SM905 profoundly inhibited disease progression, reduced IL-17A and RORgamma t mRNA expression, and suppressed pro-inflammatory mediator expression in arthritic joints. CONCLUSIONS AND IMPLICATIONS SM905 had beneficial effects on CIA by suppressing inflammatory and pathogenic Th17 responses.
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Zhou L, Jones SCP, Angen Ø, Bossé JT, Nash JHE, Frey J, Zhou R, Chen HC, Kroll JS, Rycroft AN, Langford PR. Multiplex PCR that can distinguish between immunologically cross- reactive serovar 3, 6, and 8 Actinobacillus pleuropneumoniae strains. J Clin Microbiol 2008; 46:800-3. [PMID: 18094137 PMCID: PMC2238117 DOI: 10.1128/jcm.01787-07] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 11/05/2007] [Accepted: 12/05/2007] [Indexed: 11/20/2022] Open
Abstract
We describe a highly sensitive and specific multiplex PCR, based on capsular loci and the species specific apxIV gene, that unequivocally differentiates serovar 3, 6, and 8 Actinobacillus pleuropneumoniae strains that are cross-reactive in conventional immunological tests.
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Xu K, Riaz S, Roncoroni NC, Jin Y, Hu R, Zhou R, Walker MA. Genetic and QTL analysis of resistance to Xiphinema index in a grapevine cross. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2008; 116:305-311. [PMID: 18004541 DOI: 10.1007/s00122-007-0670-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2007] [Accepted: 10/23/2007] [Indexed: 05/25/2023]
Abstract
Resistance to the dagger nematode Xiphinema index has been an important objective in grape rootstock breeding programs. This nematode not only causes severe feeding damage to the root system, but it also vectors grapevine fanleaf virus (GFLV), the causal agent of fanleaf degeneration and one of the most severe viral diseases of grape. The established screening procedures for dagger nematode resistance are time consuming and can produce inconsistent results. A fast and reliable greenhouse-based system for screening resistance to X. index that is suitable for genetic studies and capable of evaluating breeding populations is needed. In this report, the dynamics of nematode numbers, gall formation, and root weight loss were investigated using a variety of soil mixes and pot sizes over a 52-week period. Results indicated that the number of galls formed was correlated with the size of the nematode population and with the degree of root weight loss. After inoculation with 100 nematodes, gall formation could be reliably evaluated in 4-8 weeks in most plant growth conditions and results were obtained 6 months more rapidly than past evaluation methods. This modified X. index resistance screening method was successfully applied to 185 of the 188 F(1) progeny from a cross of D8909-15 x F8909-17 (the 9621 population), which segregates for a form of X. index resistance originally derived from Vitis arizonica. Quantitative trait loci (QTL) analysis was carried out on both parental genetic maps of 255 markers using MapQTL 4.0. Results revealed that X. index resistance is controlled by a major QTL, designated Xiphinema index Resistance 1 (XiR1), near marker VMC5a10 on chromosome 19. The XiR1 QTL was supported by a LOD score of 36.9 and explained 59.9% of the resistance variance in the mapping population.
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Abstract
We describe how to convert the heuristic search algorithm A* into an anytime algorithm that finds a sequence of improved solutions and eventually converges to an optimal solution. The approach we adopt uses weighted heuristic search to find an approximate solution quickly, and then continues the weighted search to find improved solutions as well as to improve a bound on the suboptimality of the current solution. When the time available to solve a search problem is limited or uncertain, this creates an anytime heuristic search algorithm that allows a flexible tradeoff between search time and solution quality. We analyze the properties of the resulting Anytime A* algorithm, and consider its performance in three domains; sliding-tile puzzles, STRIPS planning, and multiple sequence alignment. To illustrate the generality of this approach, we also describe how to transform the memory-efficient search algorithm Recursive Best-First Search (RBFS) into an anytime algorithm.
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Wang JX, Tang W, Shi LP, Wan J, Zhou R, Ni J, Fu YF, Yang YF, Li Y, Zuo JP. Investigation of the immunosuppressive activity of artemether on T-cell activation and proliferation. Br J Pharmacol 2007; 150:652-61. [PMID: 17262016 PMCID: PMC2189761 DOI: 10.1038/sj.bjp.0707137] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND AND PURPOSE Artemisinin and its derivatives exhibit potent immunosuppressive activity. The purpose of the current study was to examine the immunosuppressive activity of artemether directly on T lymphocytes and to explore its potential mode of action. EXPERIMENTAL APPROACH In vitro, T-cell proliferation was measured using [(3)H]-thymidine incorporation assay in cells stimulated with ConA, alloantigen and anti-CD3 antibody. CFSE-labeled cell division and cell cycle distribution were monitored by flow cytometry. In vivo, the effects of artemether were evaluated in delayed-type hypersensitivity (DTH) and purified T-cell responses to ovalbumin in ovalbumin-immunized mice. The activation of extracellular signal-regulated kinase1/2 (ERK1/2) and Raf1 were assessed by Western blot analysis and the activation of Ras was tested in pull-down assays. KEY RESULTS We show that, in vitro, artemether suppressed ConA- or alloantigen-induced splenocyte proliferation, influenced production of the cytokines IL-2 and IFN-gamma and inhibited cell cycle progression through the G0/G1 transition. In vivo, administration of artemether attenuated CD4 T-cell-mediated DTH reaction, and suppressed antigen-specific T-cell response in immunized mice. Further experiments showed that, treatment with artemether impaired both antigen- and anti-CD3-induced phosphorylation of ERK. In primary T cells, artemether profoundly inhibited anti-CD3-induced phosphorylation of Raf1 and activation of Ras. CONCLUSIONS AND IMPLICATIONS This study provided experimental evidence of the immunosuppressive effects of artemether directly on T cells both in vitro and in vivo. Its immunosuppressive mechanism involved inhibition of the activation of the Ras-Raf1-ERK1/2 protein kinase cascade in T cells.
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Thomas D, Dumont C, Pickup S, Misselwitz B, Zhou R, Horowitz J, Ferrari VA. T1-weighted cine FLASH is superior to IR imaging of post-infarction myocardial viability at 4.7T. J Cardiovasc Magn Reson 2006; 8:345-52. [PMID: 16669177 PMCID: PMC2581493 DOI: 10.1080/10976640500451986] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
PURPOSE Data are unavailable for rational selection of pulse sequences to assess postinfarction myocardial viability in rodents at high field strength. We implemented a widely used clinical inversion recovery (IR) sequence at 4.7T and compared the results to a heavily T1-weighted cine FLASH sequence (T1-CF) for assessment of infarction size. MATERIALS AND METHODS Eleven infarcted rats were examined within 24 h of infarction after injection of Gadophrin-3 contrast agent. Images were acquired using both pulse sequences and a standard cine (SC) sequence. Estimates of infarct size were compared to TTC. Global LV function was compared between the T1-CF and SC sequences. RESULTS SNR, relative SNR, and CNR for the infarcted and normal myocardium were significantly greater for the IR sequence. Infarction size was overestimated by both sequences, but correlated highly and showed very close agreement with TTC. Global function revealed no significant differences between T1-CF and SC. CONCLUSION Both IR and T1-CF produced reliable results for assessment of infarction size at 4.7T. While the IR sequence delivers better overall SNR and CNR, the T1-CF allows concomitant assessment of global cardiac function with a much shorter acquisition time.
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Bonham-Smith PC, Gilmer S, Zhou R, Galka M, Abrams SR. Non-lethal freezing effects on seed degreening in Brassica napus. PLANTA 2006; 224:145-54. [PMID: 16404579 DOI: 10.1007/s00425-005-0203-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2005] [Accepted: 12/06/2005] [Indexed: 05/06/2023]
Abstract
The effects of a non-lethal freezing stress on chlorophyll content, moisture level and distribution, and abscisic acid (ABA) levels were examined in siliques and seeds of Brassica napus (canola). A non-lethal freezing stress resulted in the retention of chlorophyll in seed at harvest that was most pronounced for seeds 28, 32 and 36 days after flowering (DAF). This increase was primarily due to an increased retention of chlorophyll a relative to chlorophyll b. Chlorophyll retention in seeds exposed to a non-lethal freezing stress correlated with an increased ABA catabolism, as measured 1, 3 or 7 days after the stress treatment. Although the non-lethal freezing stress had no significant effect on moisture content in seeds of siliques stressed at 28-44 DAF, moisture distribution, as viewed by magnetic resonance imaging, showed an uneven drying of 32 and 40 DAF siliques after exposure to the non-lethal freezing stress. Moisture was initially lost more rapidly from the silique wall between seeds, than in control non-stressed siliques. Increased moisture loss was not due to structural changes in the vasculature of the silique/seed of stressed tissues. These results are consistent with the hypothesis that a non-lethal freezing stress-induced decrease in ABA level, during seed maturation, effects an inhibition of normal chlorophyll a catabolism resulting in mature but green B. napus seed.
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Shi YC, Cheng HJ, Zhou R, Lu Y. Crystal structure of 1,3-benzene-bis(1-ferrocenyl-3-hydroxyprop-2-en-1-one), (C5H5)Fe(C22H16O4)Fe(C5H5). Z KRIST-NEW CRYST ST 2006. [DOI: 10.1524/ncrs.2006.0037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
AbstractC32H26Fe2O4, monoclinic, C12/c1 (no. 15), a = 19.831(4) Å, b = 9.994(2) Å, c = 25.913(5) Å, β = 94.38(3)°, V = 5120.7 Å3, Z = 8, Rgt(F) = 0.053, wRref(F2) = 0.148, T = 295 K.
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Shi YC, Cheng HJ, Zhou R, Lu Y. Crystal structure of 1,3-benzene-bis(1-ferrocenyl-3-hydroxyprop-2-en-1-one), (C5H5)Fe(C22H16O4)Fe(C5H5). Z KRIST-NEW CRYST ST 2006. [DOI: 10.1524/ncrs.2006.221.14.197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Acton PD, Zhou R. Imaging reporter genes for cell tracking with PET and SPECT. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2005; 49:349-60. [PMID: 16407818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Transplantation of cells into damaged tissue has tremendous therapeutic potential in a number of disorders, such as Parkinson's disease and myocardial infarction. Positron emission tomography (PET) and single photon emission tomography (SPECT) are highly sensitive imaging modalities, which can detect and track these cellular implants through a number of mechanisms. The stable transfection of cells with a reporter gene, which can be visualized using a radioactive PET or SPECT reporter probe, allows the repeated visualization of the migration and function of cells. These imaging techniques can be used to assess cell trafficking with methods that are easily translatable to humans. This review describes several reporter genes for PET and SPECT, and compares them against other techniques and imaging modalities.
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Wilson DT, Polunas MA, Zhou R, Halladay AK, Lowndes HE, Reuhl KR. Methylmercury Alters Eph and Ephrin Expression During Neuronal Differentiation of P19 Embryonal Carcinoma Cells. Neurotoxicology 2005; 26:661-74. [PMID: 15990172 DOI: 10.1016/j.neuro.2005.01.020] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2004] [Accepted: 01/15/2005] [Indexed: 11/19/2022]
Abstract
Developmental exposure to methylmercury (MeHg) induces a spectrum of neurological impairment characterized by cognitive disturbance, sensory/motor deficit, and diffuse structural abnormalities of the brain. These alterations may arise from neural path-finding errors during brain development, resulting from disturbances in the function of morphoregulatory guidance molecules. The Eph family of tyrosine kinase receptors and their ligands, the ephrins, guide neuronal migration and neurite pathfinding mainly via repulsive intercellular interactions. The present study examined the effects of MeHg on mRNA and protein expression profiles of Ephs and ephrins in the P19 embryonal carcinoma (EC) cell line and its neuronal derivatives. Undifferentiated control P19 cells displayed low- to undetectable levels of mRNA for ephrins or Ephs, with the sole exception of EphA2 which was highly expressed. Upon differentiation into neurons, the ephrin expression increased progressively through day 10. Similarly, expression of the Ephs, including EphsA3, -A4, -A8, -B2, -B3, -B4, and -B6, increased significantly. In contrast, EphA2 expression decreased in day 2, 6 and 10 control neurons. Treatment with MeHg did not affect the expression of mRNA for ephrins or Ephs in undifferentiated P19 cells. However, treatment of differentiating neurons with MeHg for 24 h caused consistent increases in ligand mRNA expression, particularly ephrin-A5, -A6, -B1, and -B2. Similarly, MeHg induced variable increases in mRNA expression of receptors EphA2, -A3, -B3, and -B6. A trend toward a concentration-response relationship was observed for the alterations in Eph receptor mRNA expression although increases at the low and mid concentrations did not reach statistical significance. Immunoblots for ligand and receptor proteins mirrored the increases in the mRNA levels at the 0.5 and 1.5 microM MeHg concentrations but showed decreased protein levels compared to controls at the 3.0 microM concentration. Alterations in the Eph/ephrin family of repulsion molecules may represent an important mechanism in developmental MeHg neurotoxicity.
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Thomas D, Pickup S, Zhou R, Glickson J, Ferrari VA. Homogene Strain-Analyse im Vergleich zur Wanddickenzunahme für die MR-tomographische Beurteilung der regionalen Myokardfunktion. ROFO-FORTSCHR RONTG 2005; 177:975-85. [PMID: 15973600 DOI: 10.1055/s-2005-858269] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To compare strain analysis and wall thickening (WT) analysis in differentiating the infarcted, adjacent, and remote zones in a rat model of myocardial infarction (MI). MATERIAL AND METHODS Three normal (NL) and ten rats subjected to myocardial infarction were imaged on a 4.7T scanner. Gradient-echo and SPAMM-tagged cine images were acquired at three short axis levels of the left ventricle (LV). A homogenous strain analysis (principal strains lambda1 and lambda2, displacement D, angle beta) and a WT-analysis (mm- and %-thickening) were performed in all slices demonstrating MI. Regional function was compared between infarcted rats (infarcted, adjacent and remote zone) and corresponding regions in the NL rats. Additional segmental analysis was performed in the NL rats for the anterior, lateral, inferior and septal wall. RESULTS In the NL rats, lambda (1) (greatest radial thickening) was greatest in the lateral and anterior wall. WT-analysis showed a pattern of function similar to lambda1, however, regional differences using WT-analysis were not significant. lambda (2) (greatest circumferential shortening) was most negative in the anterior wall. D was greatest in the lateral and inferior wall. The angle beta was radially directed in all segments. In the infarcted rats, both strain and WT-analyses revealed significant impairment in function in the infarcted and adjacent zones as compared to NL (p < 0.001). However, only the strain analysis (lambda1, lambda2, p < 0.001) detected significant remote myocardial dysfunction. Myocardial function differed significantly between the infarcted and adjacent and between the infarcted and remote regions. Strain analysis (lambda2, D, beta, p < 0.001) also identified significant functional differences between the adjacent and remote zones, however, no statistically significant differences were found using WT-analysis. CONCLUSION Strain analysis is superior to WT-analysis in detecting regional functional variations in NL rats and in discriminating function in the infarcted, adjacent and remote zones post MI.
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Stec B, Zhou R, Teeter MM. Full-matrix refinement of the protein crambin at 0.83 A and 130 K. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2005; 51:663-81. [PMID: 15299796 DOI: 10.1107/s0907444994014484] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This paper describes the first successful full-matrix least-squares (FMLS) refinement of a protein structure. The example used is crambin which is a small hydrophobic protein (4.7 kDa, 46 residues). It proves the feasibility of refining such large molecules by this classic method, routinely applied to small molecules. The final structure with 381 non-H protein atoms (54 protein atoms in alternative positions), 367 H atoms, 162 water molecules (combined occupancy 93) and one disordered ethanol molecule converged to a standard unweighted crystallographic R-factor of R = 9.0% when refined against F with reflections stronger than F > 2sigma(F) and R = 9.5% when refined against F(2). The programs RFINE [Finger & Prince (1975). Natl Bur. Stand. (US) Tech. Note 854. A System of Fortran IV Computer Programs for Crystal Structure Computations] and SHELXL93 [Sheldrick (1993). SHELXL93. Program for Crystal Structure Refinement, Univ. of Göttingen, Germany] were used for FMLS refinement with the high-resolution low-temperature (0.83 A, 130 K) data set of a mixed-sequence form of crambin. A detailed analysis of the models obtained in FMLS and PROLSQ [restrained least squares or RLS; Teeter, Roe & Heo (1993). J. Mol. Biol. 230, 292-311] refinements with the same data set is presented. The differences between the models obtained by both FMLS and RLS refinements are systematic but negligible and advantages and shortcomings of both methods are discussed. The final structure has very good geometry, fully comparable to the geometry of other structures in this resolution range. Ideal values used in PROLSQ and those by Engh & Huber [Engh & Huber (1991). Acta Cryst. A47, 392-400] differ significantly from this refinement and we recommend a new standard. FMLS refinement constitutes a sensitive tool to detect and model disorder in highly refined protein structures. We describe the modeling of temperature factors by the TLS method [Schomaker & Trueblood (1968). Acta Cryst. B24, 63-76]. Rigid body-TLS refinements led to a better understanding of different modes of vibrations of the molecule. Refinements using F(2) or F protocols converged and reached slightly different minima. Despite theoretical support for F(2)-based refinement, we recommend refinement on structure factors.
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Thomas D, Ferrari VA, Janik M, Kim DH, Pickup S, Glickson JD, Zhou R. Quantitative assessment of regional myocardial function in a rat model of myocardial infarction using tagged MRI. MAGNETIC RESONANCE MATERIALS IN PHYSICS BIOLOGY AND MEDICINE 2004; 17:179-87. [PMID: 15517473 PMCID: PMC2964083 DOI: 10.1007/s10334-004-0051-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2004] [Accepted: 07/15/2004] [Indexed: 10/26/2022]
Abstract
We characterized global and regional left ventricular (LV) function during post myocardium infarction (MI) remodeling in rats, which has been incompletely described by previous MRI studies. To assess regional wall motion, four groups of infarcted animals corresponding to 1-2, 3-4, 6-8 and 9-12 weeks post-MI respectively were imaged using a fast gradient echo sequence with a 2D spatial modulation of magnetization (SPAMM) tagging preparation. An additional group was serially imaged (1-2 and 6-7 weeks post-MI) to assess the global function. Regional and global functional parameters of infarcted rats were compared to non-infarcted normal rats. Compared to normal rats, a decrease in ejection fraction (70 +/-7 vs. 40 +/- 8%, p<0.05) was observed in rats with MI. Maximal and minimal principal stretches (lambda1, lambda2) and strains (E1, E2), principal angle (beta) and displacement varied regionally in normal rats but deviated significantly from the normal values in rats with MI particularly in the infarcted and adjacent zones. Not only was strain magnitude reduced segmentally post-MI, but strain direction became more circumferentially oriented, particularly in rats with larger infarctions. We report the first regional myocardial strain values in normal and infarcted rats. These results parallel findings in humans, and provide a unique tool to examine regional mechanical influences on the remodeling process.
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Halladay AK, Tessarollo L, Zhou R, Wagner GC. Neurochemical and behavioral deficits consequent to expression of a dominant negative EphA5 receptor. ACTA ACUST UNITED AC 2004; 123:104-11. [PMID: 15046871 DOI: 10.1016/j.molbrainres.2004.01.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2004] [Indexed: 11/29/2022]
Abstract
The Eph family tyrosine kinase receptors and their ligands have been linked to axon guidance and topographic mapping of the developing central nervous system. More specifically, the EphA5 receptor has been shown to play a role in development of hippocamposeptal, retinotectal and thalamocortical projections. Recently, a line of transgenic mice was developed which expresses a truncated EphA5 receptor lacking a functional tyrosine kinase domain. In a previous study, axonal tracing revealed that medial hippocampal axons in this strain projected laterally and ventrally away from their normal target area. In the current study, both transgenic and wild-type controls were evaluated in unconditioned (rotorod and locomotor activity) and conditioned (water maze and active avoidance) behavior tasks which tested hippocampal and striatal functioning. Compared to controls, the transgenic strain did not show differences in rotorod motor activity but did show a transient deficit in spatial navigation ability and a consistent impairment in active avoidance. The dominant-negative mutant receptor also resulted in a decrease in striatal dopamine and serotonin concentrations with no change in hippocampal monoamines. Collectively, these data suggest that animals expressing a truncated EphA5 receptor show deficits related to striatal functioning.
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224
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Zhou R, Flaswinkel H, Schneider MR, Lahm H, Hoeflich A, Wanke R, Wolf E. Insulin-like growth factor-binding protein-4 inhibits growth of the thymus in transgenic mice. J Mol Endocrinol 2004; 32:349-64. [PMID: 15072544 DOI: 10.1677/jme.0.0320349] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Numerous in vitro studies have demonstrated that IGF-binding protein (IGFBP)-4 is a consistent inhibitor of IGF actions. In order to investigate the functions of IGFBP-4 in vivo, transgenic mice were generated by microinjection of a transgene, in which the murine Igfbp4 cDNA is driven by the H-2K(b) promoter, and followed by a splicing cassette and polyadenylation signal of the human beta-globin gene. Transgene mRNA was expressed ubiquitously, and elevated IGFBP-4 protein was detected in the spleen, thymus, kidney and lung of transgenic mice. The activities of serum IGFBPs were not changed in transgenic mice. Immunohistochemical studies revealed transgene expression predominantly in the thymic medulla and red pulp of the spleen. Body weight and the weights of the spleen, kidney and lung of transgenic mice were not different from controls. In contrast, the thymus of transgenic mice showed a significantly reduced weight and cortex volume. In transgenic thymus and spleen, cell proliferation was inhibited and apoptosis was stimulated. Transgenic mice showed normal T- and B-cell development and normal basal plasma immunoglobulin levels. In conclusion, overexpression of IGFBP-4 inhibits growth of the thymus. IGFBP-4 excess inhibits cell proliferation and stimulates apoptosis in lymphoid tissues, but does not affect lymphocyte development. These findings suggest that IGFBP-4 is a potential growth inhibitor of lymphoid tissues.
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Zhou R, Flaswinkel H, Schneider MR, Lahm H, Hoeflich A, Wanke R, Wolf E. Overexpression of insulin-like growth factor-binding protein-4 inhibits cell proliferation and stimulates apoptosis in the spleen and thymus of transgenic mice. Exp Clin Endocrinol Diabetes 2004. [DOI: 10.1055/s-2004-819203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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226
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Cheng H, Guo Y, Yu Q, Zhou R. The rice field eel as a model system for vertebrate sexual development. Cytogenet Genome Res 2004; 101:274-7. [PMID: 14684994 DOI: 10.1159/000074348] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2003] [Accepted: 06/11/2003] [Indexed: 11/19/2022] Open
Abstract
Complex developmental mechanisms of vertebrates are unraveled using comparative genomic approaches. Several teleosts, such as zebrafish, medaka and pufferfish, are used as genetic model systems because they are amenable to studies of gene function. The rice field eel, a freshwater fish, is emerging as a specific model system for studies of vertebrate sexual development because of its small genome size and naturally occurring sex reversal. Data presented here support the use of the rice field eel as another important fish model for comparative genome studies, especially in vertebrate sexual development. This model system is complementary rather than redundant.
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Wang W, Fu Q, Zhou R, Wu W, Ding Q, Hu Y, Wang X, Wang H, Wang Z. Prothrombin Shanghai: hypoprothrombinaemia caused by substitution of Gla29 by Gly. Haemophilia 2004; 10:94-7. [PMID: 14962227 DOI: 10.1046/j.1365-2516.2003.00838.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Prothrombin deficiency is a rare bleeding disorder inherited as an autosomal recessive trait. In this study, we reported a Chinese family with hereditary prothrombin deficiency. The proposita had a prolonged activated partial thromboplastin time (APTT, 71.6 s) and prothrombin time (PT, 28.0 s). The coagulation factors activities were normal except that prothrombin coagulation activity was markedly reduced, and the prothrombin antigen level was moderately decreased. Nucleotide sequencing of amplified DNA revealed a novel mutation, Glu (GAG) to Gly (GGG) at residue 29, which normally undergoes gamma-carboxylation within the Gla domain of prothrombin. The proposita was identified as homozygous, while her father, mother and maternal grandmother were heterozygous for the mutation. Gla29 has been demonstrated as one of the key residue for Ca2+-binding, membrane interaction and biological activity of prothrombin.
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228
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Zhou R, Diehl D, Hoeflich A, Lahm H, Wolf E. IGF-binding protein-4: biochemical characteristics and functional consequences. J Endocrinol 2003; 178:177-93. [PMID: 12904166 DOI: 10.1677/joe.0.1780177] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
IGFs have multiple functions regarding cellular growth, survival and differentiation under different physiological and pathological conditions. IGF effects are modulated systemically and locally by six high-affinity IGF-binding proteins (IGFBP-1 to -6). Despite their structural similarity, each IGFBP has unique properties and exhibits specific functions. IGFBP-4, the smallest IGFBP, exists in both non-glycosylated and N-glycosylated forms in all biological fluids. It is expressed by a wide range of cell types and tIssues, and its expression is regulated by different mechanisms in a cell type-specific manner. IGFBP-4 binds IGF-I and IGF-II with similar affinities and inhibits their actions under almost all in vitro and in vivo conditions. In this review, we summarize the available data regarding the following aspects of IGFBP-4: genomic organization, protein structure-function relationship, expression and its regulation, as well as IGF-dependent and -independent actions. The biological significance of IGFBP-4 for reproductive physiology, bone formation, renal pathophysiology and cancer is discussed.
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Bivén K, Erdal H, Hägg M, Ueno T, Zhou R, Lynch M, Rowley B, Wood J, Zhang C, Toi M, Shoshan MC, Linder S. A novel assay for discovery and characterization of pro-apoptotic drugs and for monitoring apoptosis in patient sera. Apoptosis 2003; 8:263-8. [PMID: 12766486 DOI: 10.1023/a:1023672805949] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
We have developed an apoptosis assay based on measurement of a neoepitope of cytokeratin-18 (CK18-Asp396) exposed after caspase-cleavage and detected by the monoclonal antibody M30. The total amount of caspase-cleaved CK18 which has accumulated in cells and tissue culture media during apoptosis is measured by ELISA. The sensitivity is sufficient for use in the 96-well format to allow high-through-put screening of drug libraries. We here describe strategies allowing classification of pro-apoptotic compounds according to their profiles of induction of apoptosis in the presence of pharmacological inhibitors. The time course of induction of CK18 cleavage can furthermore be used to distinguish structurally similar compounds. We propose that compounds that induce rapid CK18 cleavage have mechanisms of actions distinct from conventional genotoxic and microtubuli-targeting agents, and we present one example of an agent that induces almost immediate mitochondrial depolarization and cytochrome c release. Finally, CK18-Asp396 cleavage products are released from cells in tissue culture, and presumably from tumor cells in vivo. These products can be measured in sera from cancer patients. We present evidence suggesting that it will be possible to use the M30-ELISA assay for measuring chemotherapy-induced apoptosis in patient sera, opening possibilities for monitoring therapy.
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230
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Morita M, Nishi K, Kimura T, Fukushima M, Watanabe T, Yamashita F, Zhou R, Yang J, Xu X. Correlation between periodontal status and biting ability in Chinese adult population. J Oral Rehabil 2003; 30:260-4. [PMID: 12588497 DOI: 10.1046/j.1365-2842.2003.01012.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This study investigated the relation between periodontal condition and biting ability in a Chinese population using the pressure-detecting sheet. A total of 142 subjects residing in Nanchang, Jiangxi province, China, participated in the study. The examination included probing pocket depth (PD), clinical attachment level (CAL), bleeding on probing and coronal caries teeth. Biting abilities per person, biting force, biting pressure and occlusal contact area were measured using the sheet. Number of teeth present showed positive correlation with biting force and occlusal contact area, but were negatively correlated with biting pressure. No significant correlation was observed between the mean PD, percentage of pocket > or = 4 mm, bleeding index and any of biting abilities. The mean CAL showed a significantly negative correlation with biting force and occlusal contact area. Multiple stepwise regression analysis selected the number of teeth present, sex and age as the significant factors affecting the biting ability. However, no periodontal indices were picked up as the significantly contributing factor. There appears to be little effect of periodontal condition on biting ability. Ageing was selected as a contributing factor to reduction in the Chinese adults, but not in the Japanese population.
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231
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Dumesic D, Schramm R, Peterson E, Paprocki A, Zhou R, Abbott D. Premature follicle luteinization as a paracrine regulator of androstenedione (A4) in prenatally androgenized (PA) female rhesus monkeys receiving follicle-stimulating hormone (FSH) therapy for in vitro fertilization (IVF). Fertil Steril 2002. [DOI: 10.1016/s0015-0282(02)03469-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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232
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Lin YG, Zhou R, Chien JCW, Winter HH. Rheology of a twin liquid crystalline polymer. Macromolecules 2002. [DOI: 10.1021/ma00185a022] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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233
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Luo H, Cheng P, Zhou R. [Sequential BiPAP following invasive mechanical ventilation in COPD patients with hypercapnic respiratory failure]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:563-5. [PMID: 12536544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To estimate the feasibility and the efficacy of extubation and sequential bilevel positive airway pressure (BiPAP) in chronic obstructive pulmonary disease (COPD) patients with exacerbated hypercapnic respiratory failure. METHODS All patients were randomly divided into a control group and an experimental group. In addition to conventional therapy, the experimental group was treated with bilevel positive airway pressure via facial mask immediately, the control group was treated with conventional therapy alone. RESULTS There were no difference in clinical characteristics and gas exchange at entry. pH value, PaCO2 and PaCO2 were significantly improved in experimental group following the first 45 minutes ventilation (P < 0.05), but no additional improvement was observed when ventilation was extended to 12 hours (P > 0.05). Reintubation rate was higher in the control group compared with the experimental group (P < 0.05). CONCLUSION BiPAP can be well tolerated, and can improve ventilation function markedly. It can also facifiated the extubation, and reduced the reintubation rate in regular mechanical ventilation.
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234
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Zhou R, Berne BJ, Germain R. The free energy landscape for beta hairpin folding in explicit water. Proc Natl Acad Sci U S A 2001; 98:14931-6. [PMID: 11752441 PMCID: PMC64961 DOI: 10.1073/pnas.201543998] [Citation(s) in RCA: 396] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2001] [Indexed: 11/18/2022] Open
Abstract
The folding free energy landscape of the C-terminal beta hairpin of protein G has been explored in this study with explicit solvent under periodic boundary condition and OPLSAA force field. A highly parallel replica exchange method that combines molecular dynamics trajectories with a temperature exchange Monte Carlo process is used for sampling with the help of a new efficient algorithm P3ME/RESPA. The simulation results show that the hydrophobic core and the beta strand hydrogen bond form at roughly the same time. The free energy landscape with respect to various reaction coordinates is found to be rugged at low temperatures and becomes a smooth funnel-like landscape at about 360 K. In contrast to some very recent studies, no significant helical content has been found in our simulation at all temperatures studied. The beta hairpin population and hydrogen-bond probability are in reasonable agreement with the experiment at biological temperature, but both decay more slowly than the experiment with temperature.
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235
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Zhou X, Suh J, Cerretti DP, Zhou R, DiCicco-Bloom E. Ephrins stimulate neurite outgrowth during early cortical neurogenesis. J Neurosci Res 2001; 66:1054-63. [PMID: 11746437 DOI: 10.1002/jnr.10029] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The Eph receptor ligands, the ephrins, are membrane-bound molecules that play important roles in establishing intercellular communication after neurogenesis by regulating cell migration, axon pathfinding, and topographic mapping. In diverse systems, such as embryonic day 17.5 (E17.5) hippocampal and cortical neurons, repulsive/inhibitory mechanisms underlie these cellular effects. However, although ligand/receptor expression occurs far earlier, during brain neurogenesis, little is known about potential ephrin functions in initial process outgrowth. We have examined ligand/receptor expression in E13.5 cortex in vivo and in culture, using alkaline phosphatase (AP)-conjugated reagents and RNase protection assay. B ephrins are highly expressed, including B1, B2, and B3, whereas A ephrins exhibit low expression levels. In contrast, the Eph receptors demonstrate an opposite pattern, exhibiting high levels of Eph A3, A4, and A5 mRNA transcripts and low levels of the B-class receptors. To examine effects on neurite outgrowth, soluble ephrins were incubated with antihuman IgG antibody, producing oligomeric agonist complexes, and dried onto culture dishes. Unexpectedly, both ephrin A and B complexes increased process outgrowth: Seventy to eighty percent of neuronal precursors exhibited long neurites on ephrins, whereas only 5-10% of cells had neurites on IgG control substrates, indicating that ephrins stimulated neuritogenesis by early cortical neurons. These observations suggest that ephrin ligand/receptor systems play ontogenetic roles not previously considered, activating mechanisms other than cellular repulsion. Ephrin systems may induce initial process elaboration by early cortical neurons that is restricted at later stages by well-characterized repulsive signaling mechanisms.
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236
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Zhang W, Zhou R, Chen P, He P. [Study on expression of caspase-3 and bcl-2 proteins and their relations with cell apoptosis and proliferation in non-Hodgkin's lymphoma]. ZHONGHUA BING LI XUE ZA ZHI = CHINESE JOURNAL OF PATHOLOGY 2001; 30:434-8. [PMID: 11866986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
OBJECTIVE To explore the possible roles of caspase-3 and bcl-2 proteins in the development and progression of non-Hodgkin's lymphoma (NHL) and their relationship. METHODS TdT-mediated dUTP nick end labeling (TUNEL) and immunohistochemistry were used to study cell apoptosis and expression of proliferating cell nuclear antigen (PCNA), caspase-3 and bcl-2 in 119 NHL cases. RESULTS The caspase-3 and bcl-2 positive rates were 86.6% (103/119) and 53.8% (64/119) respectively. Contrasting expression of these two proteins were found in reactive and malignant lymphoid tissues: In reactive lymphoid follicles, caspases-3 exhibited strong immunoactivity in cells located in germinal centers but not in mantle zone lymphocytes, whereas bcl-2 exhibited strong immunoactivity in mantle zone lymphocytes but not in cells located in germinal centers, and in neoplastic follicles, caspase-3 was negatively or weakly expressed, whereas bcl-2 was often positively expressed. In B cell lymphomas, the high grade group had a higher caspase-3 immunointensity and a lower bcl-2 immunointensity than the low grade group (P < 0.01). Apoptotic index correlated positively with expression of caspase-3 (r = 0.512, P < 0.01) and inversely with expression of bcl-2 (r = -0.436, P < 0.01). In addition, apoptotic index and proliferative index were positively related (r = 0.710, P < 0.01). CONCLUSIONS caspase-3 may participate in the regulation mechanism of lymphoma cell apoptosis. The contrasting expression of caspase-3 and bcl-2 is often seen in reactive and malignant lymphoid tissues, and it may indicate a close relationship between these two proteins in the regulation of lymphocyte proliferation kinetics.
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Li YY, Mi Z, Feng Y, McTiernan CF, Zhou R, Robbins PD, Watkins SC, Feldman AM. Differential effects of overexpression of two forms of ephrin-A5 on neonatal rat cardiomyocytes. Am J Physiol Heart Circ Physiol 2001; 281:H2738-46. [PMID: 11709443 DOI: 10.1152/ajpheart.2001.281.6.h2738] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Eph receptors constitute the largest family of receptor tyrosine kinases. Multiple transcripts of ephrin-A5, the cognate ligand of the EphA3 receptor, were found in neonatal rat cardiomyocytes. Two cDNA clones encoding the full-length ephrin-A5 (ephrin-A5 alpha) and a 27-amino acid deletion form (ephrin-A5 beta) were isolated. To examine the role of ephrin-A5 in cardiomyocytes, the cDNAs were inserted into adenoviral vectors, termed Ad.ephrin-A5 alpha and Ad.ephrin-A5 beta, respectively, and overexpressed in cardiomyocytes. The effect of ephrin-A5 on cardiomyocyte gene expression was investigated using a cDNA expression array and Western blot analysis. The results showed that both ephrin-A5 alpha and ephrin-A5 beta downregulated cyclin D2, cyclin-dependent kinase-4 proteins, and their cognate receptor EphA3, which were associated with reduced bromodeoxyuridine incorporation in cardiomyocytes. Whereas ephrin-A5 alpha and ephrin-A5 beta also induced differential gene expression, only ephrin-A5 beta significantly upregulated the transcription of brain natriuretic peptide and downregulated ras-related protein RAB2, protein kinase C inhibitor protein-1, clusterin, and insulin-like growth factor-binding protein. The results suggest that the two forms of ephrin-A5 share similar function while differ in regulating different sets of genes in cardiomyocytes.
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Yang X, Yang Y, Zhou R, Bian L. [Determination of total, soluble and insoluble dietary fiber in foods by enzymatic-gravimetric method]. WEI SHENG YAN JIU = JOURNAL OF HYGIENE RESEARCH 2001; 30:377-8, back cover. [PMID: 12561627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
For studying the contents of dietary fiber in general foods and functional foods, a enzymatic-gravimetric method recommended by AOAC was established in our laboratory. The method for the determination of total, soluble and insoluble dietary fiber in foods and functional foods could be used for many other kind of foods. The relative standard deviations (RSD) of reproducibility between-run and within-run were 2.04%-7.85%, 3.42%-55.23% respectively. The repeatability of the methods was good, and the methods are suitable for many foods.
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Zhou R, Zettl A, Ströbel P, Wagner K, Müller-Hermelink HK, Zhang S, Marx A, Starostik P. Thymic epithelial tumors can develop along two different pathogenetic pathways. THE AMERICAN JOURNAL OF PATHOLOGY 2001; 159:1853-60. [PMID: 11696445 PMCID: PMC1867047 DOI: 10.1016/s0002-9440(10)63031-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
To investigate genetic abnormalities associated with the development of thymic epithelial tumors, we performed microsatellite analysis of 26 thymomas belonging to three different World Health Organization types (A, B3, and C) using 48 repeats. The most frequent aberration seen was loss of heterozygosity (LOH) in the region 6q23.3-25.3 detected in 11 tumors (45.8% of informative cases). Further consistent LOHs were detected in regions 3p22-24.2, 3p14.2 (FHIT gene locus), 5q21 (APC), 6p21, 6q21-22.1, 7p21-22, 8q11.21-23, 13q14 (RB), and 17p13.1 (p53). Microsatellite instability was extremely rare, occurring in one type B3 thymoma only, although, at 12.5% of the analyzed loci. Comparing the allelotypes of the analyzed thymomas, we were able to identify two pathogenetic pathways these tumors develop along, characterized by the 6q23.3-25.3 and 5q21 LOHs, respectively. The APC aberration on 5q21 showed significant associations with LOH in the 3p22-24.2, 13q14, and 17p13.1 regions. Interestingly, type A thymomas presented with consistent LOH in the region 6q23.3-25.5 only, they did not reveal any aberrations in the APC, RB, and p53 gene loci or regions 3p22-24.2 and 8q11.21-23. The absence of these aberrations might be the reason for the well-known benign behavior of type A thymomas as compared to types B3 and C tumors.
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Schneider MR, Zhou R, Hoeflich A, Krebs O, Schmidt J, Mohan S, Wolf E, Lahm H. Insulin-like growth factor-binding protein-5 inhibits growth and induces differentiation of mouse osteosarcoma cells. Biochem Biophys Res Commun 2001; 288:435-42. [PMID: 11606061 DOI: 10.1006/bbrc.2001.5785] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The precise role of insulin-like growth factor-binding protein-5 (IGFBP-5) in regulating the growth of tumor cells, especially of bone-derived malignant cells, is not well understood. We have investigated the biological activity of IGFBP-5 by transfecting OS/50-K8 mouse osteosarcoma cells with an expression vector containing the osteocalcin promoter and the complete mouse IGFBP-5 cDNA (OC-IGFBP-5). Overexpression of IGFBP-5 mRNA and secretion of increased amounts of bioactive protein in conditioned media were demonstrated in different clones. For the analysis of cell proliferation, three clones exhibiting high levels of IGFBP-5 expression were selected and compared to a mock clone and to nontransfected parental cells. IGFBP-5-secreting clones displayed reduced proliferation under both anchorage-dependent and -independent conditions (P < 0.05). The increase in proliferation observed in IGFBP-5-secreting clones after addition of exogenous IGF was significantly lower than that observed in mock-transfected or parental cells. A similar result was obtained with long[R3]IGF-I which has a low affinity for all IGFBPs, suggesting that the inhibitory effect of IGFBP-5 is only partially IGF-dependent. OC-IGFBP-5-transfected clones expressed significantly higher amounts of osteocalcin mRNA (P < 0.05) and secreted more osteocalcin protein than a mock clone or parental OS-50/K8 cells. Thus, part of the growth-inhibiting effect of IGFBP-5 may be due to an induction of differentiation in these cells.
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Webber SE, Marakovits JT, Dragovich PS, Prins TJ, Zhou R, Fuhrman SA, Patick AK, Matthews DA, Lee CA, Srinivasan B, Moran T, Ford CE, Brothers MA, Harr JE, Meador JW, Ferre RA, Worland ST. Design and synthesis of irreversible depsipeptidyl human rhinovirus 3C protease inhibitors. Bioorg Med Chem Lett 2001; 11:2683-6. [PMID: 11591501 DOI: 10.1016/s0960-894x(01)00542-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Novel tripeptidyl C-terminal Michael acceptors with an ester replacement of the P(2)-P(3) amide bond were investigated as irreversible inhibitors of the human rhinovirus (HRV) 3C protease (3CP). When screened against HRV serotype-14 the best compound was shown to have very good 3CP inhibition (k(obs)/[I]=270,000M(-1)s(-1)) and potent in vitro antiviral activity (EC(50)=7.0nM).
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Dumesic D, Schramm R, Paprocki A, Zhou R, Peterson E, Abbott D. Interaction between luteinizing hormone (LH) and insulin (I) during gonadotropin stimulation for in vitro fertilization (IVF) affects intrafollicular steroidogenesis in prenatally androgenized female rhesus monkeys. Fertil Steril 2001. [DOI: 10.1016/s0015-0282(01)02320-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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243
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Huang W, Zhou X, Huang X, Peng Y, Su Y, Qiao L, Zhou S, Fang F, Zhou R, Li S, Han Z. [Clindamycin soluble suppository-production and its efficacy in treating bacterial vaginosis]. HUA XI YI KE DA XUE XUE BAO = JOURNAL OF WEST CHINA UNIVERSITY OF MEDICAL SCIENCES = HUAXI YIKE DAXUE XUEBAO 2001; 32:452-3, 458. [PMID: 12536592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To make the soluble suppository of clindamycin which is an effective drug for treatment of Bacterial vaginosis and to treat patients in clinical trials. METHODS Outpatients who had vaginal infections from Sept. 1998 to Jan. 1999 were investigated. The diagnoses of bacterial vaginosis were made according to Amsel's criteria and 80 patients were included in this study. They were divided into two groups to be treated respectively by metronidanole suppository and clindamycin suppository which were made by our hospital pharmacy. RESULTS The cure rate of metronidanole was 87.5% and that of clindamycin 90.3%; No significant difference was noted between the two groups(P > 0.05). The new clindamycin suppository was not irritant and it was easy to dissolve in vagina. There was no discontinued treatment because of side-effect. CONCLUSION The clindamycin suppository does not irritate the mucosa of vagina, it is an efficacious remedy for bacterial vaginosis.
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Zhou R, Wu X, Skalli O. TGF-alpha induces a stationary, radial-glia like phenotype in cultured astrocytes. Brain Res Bull 2001; 56:37-42. [PMID: 11604246 DOI: 10.1016/s0361-9230(01)00591-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Transgenic mice studies have suggested that transforming growth factor-alpha (TGF-alpha) influences the postnatal differentiation of astrocytes. To understand the role of TGF-alpha during astrocytic differentiation, it is important to determine how this factor affects astrocytes in the absence of other influences. We have thus examined in vitro under serum-free medium conditions the effect of TGF-alpha on the properties of astrocytes derived from the cerebral cortex of newborn rats. When TGF-alpha is added to serum-free medium, most astrocytes lose their polygonal shape and extend two long processes running in opposite directions. This bipolar morphology strikingly resembles that of radial glial cells. Intriguingly, serum inhibits this morphological transformation. TGF-alpha also triggers an increase in glial fibrillary acidic protein (GFAP) expression and a decrease in nestin expression. Another major effect of TGF-alpha is to practically abolish the motility of astrocytes. TGF-alpha, however, does not appear to influence the proliferation and apoptosis of astrocytes. These results suggest that polygonal astrocytes are derived primarily from radial glial cells, and that in vivo TGF-alpha may be instrumental in determining the shape and migratory potential of radial glial cells.
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Zhou R, Bansal N, Leeper DB, Pickup S, Glickson JD. Enhancement of hyperglycemia-induced acidification of human melanoma xenografts with inhibitors of respiration and ion transport. Acad Radiol 2001; 8:571-82. [PMID: 11450957 DOI: 10.1016/s1076-6332(03)80681-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
RATIONALE AND OBJECTIVES The authors performed this study to evaluate the selective acidification of a human melanoma xenograft in mice with severe combined immunodeficiency with the induction of hyperglycemia (mean blood glucose level +/- standard error of the mean, 26 mmol/L +/- 1) and the intraperitoneal administration of metaiodobenzylguanidine (MIBG, 30 mg/kg), alpha-cyano-4-hydroxycinnamate (CNCn, 300 mg/kg), lonidamine (100 mg/kg), cariporide (HOE642, 160 mg/kg), or 4.4'-diisothiocyanatostilbene-2, 2'-disulfonic acid (DIDS, 50 mg/kg). MATERIALS AND METHODS The intra- and extracellular pH levels of tumor were estimated from the chemical shifts of inorganic phosphate and 3-aminopropylphosphonate, respectively, with phosphorus-31 nuclear magnetic resonance (MR) spectroscopy. The relative level of steady-state lactate was monitored with hydrogen-1 MR spectroscopy. RESULTS In small tumors (< or = 8.0 mm), hyperglycemia decreased the intra- and extracellular pH levels by less than 0.2. The combination of hyperglycemia and MIBG decreased the intra- and extracellular pH levels by approximately 0.4 and 0.6, respectively, and lowered the beta-nucleoside triphosphate (NTP)/inorganic phosphate (Pi) ratio of tumor and liver by about 60% and 25%, respectively. The combination of hyperglycemia, MIBG, and CNCn produced a transient decrease in the intracellular pH of about 0.6. The combination of hyperglycemia and lonidamine produced a sustained (>3 hours) 0.8-unit decrease in intracellular pH and an 83% and 100% decrease in PCr/P1 and beta-NTP/P1 ratios, respectively. The combination of hyperglycemia. MIBG, cariporide, and DIDS produced a gradual decrease in intra- and extracellular pH by 1.1 and 1.0, respectively. The relative level of steady-state lactate concentration in tumors increased 10% with hyperglycemia alone, about 20% with MIBG plus hyperglycemia, and increased more than twofold when hyperglycemia was combined with MIBG and CNCn administration. CONCLUSION These preliminary data suggest that hyperglycemia and combinations of respiratory and ion transport inhibitors can be used to selectively acidify tumors and, thereby, sensitize them to hyperthermnia or other pH-sensitive therapeutic modalities.
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Zhou R, Chen P, Luo H, Xiang XD. [Effects of noninvasive positive pressure ventilation on gas exchange and patients' transformation in chronic obstructive pulmonary disease and respiratory failure]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:261-2. [PMID: 12536700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE This paper was to observe the effects of noninvasive positive pressure ventilation (NPPV) on gas exchange and patients' transformation and to evaluate their clinical value. METHODS Patients were randomly treated by either NPPV, or conventional medicine. The arterial blood gas readings, heart rates (HR), and respiratory rates (HR) were obtained at admission after the treatment. It was necessary to intubate when the clinical deterioation was marked by PaCO2 > 70 mmHg, PaCO2 gradually increasing 5-10 mmHg, pH decreasing 0.05-0.1 or mental obstacle, or PaO2 < 45 mmHg. RESULTS NPPV significantly decreased the PaCO2 level, HR, and RR, significantly increased the PaO2 level, and also decreased the opportunity of intubation. CONCLUSION The results suggest that NPPV can improve the gas exchange and reduce the need of intubation in COPD patients with acute respiratory failure.
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Xiang XD, Zhou R, Chen Y. [Influence of zafirlukast on pulmonary functions and quality of life in patients with asthma]. HUNAN YI KE DA XUE XUE BAO = HUNAN YIKE DAXUE XUEBAO = BULLETIN OF HUNAN MEDICAL UNIVERSITY 2001; 26:251-3. [PMID: 12536697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVES To explore the influence of zafirlukast on pulmonary functions and quality of life (QOL) in patients with mild-to-moderate asthma at the stage of attack and at the stable stage. METHODS Patients at the stage of attack were randomly divided into two groups: Group one is zafirlukast 20 mg twice daily plus inhaled the half quantity of glucocorticoid(budelade) of the Global Initiative for Asthma (GINA) standard quantity, long-effection aminophyllin 0.2 g twice daily and inhaled salbutamol when necessary; Group two: inhaled budelade of GINA standard quantity, long-effection aminophyllin 0.2 g twice daily and inhaled salbutamol when necessary). Patients' peak expiratory flow (PEF)/PEF predicted value % and delta PEFR% were determined at the second week and the forth week before and after the treatment. On the standard treatment, patients with the stable stage were added zafirlukast 20 mg twice a day. PEF values in the morning and evening and QOL were evaluated. RESULTS After treating with zafirlukast, the PEF/PEF predicted value % and delta PEFR% in Group one were higher and lower than those of Group two respevtively. These changes were appeared in two days and were peaked in two weeks and the peak had been gone on for more than 4 weeks, but these were no significant difference between the Groups (P > 0.05); PEF values in the morning and evening in patients with the stable asthma increased 5.9% and 4.6% respectively and their QOL were improved in asthma symptoms, limitative activities, avoiding stimuli, and reacting on stimuli. CONCLUSION Zafirlukast can improve pulmonary function, reduce the inhalation quantity of steroid in patients with mild-to-moderate asthma, and play an important role in treating and improving QOL in patients with the stable asthma.
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Zhou R, Frostvik-Stolt M, Liliemark E. Determination of etoposide in human plasma and leukemic cells by high-performance liquid chromatography with electrochemical detection. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 757:135-41. [PMID: 11419738 DOI: 10.1016/s0378-4347(01)00133-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This paper describes a high-performance liquid chromatographic method with electrochemical detection for the determination of etoposide levels in plasma, total and non-protein bound concentration, and in leukemic cells. The precision for between-runs (n=6) was 7.0, 4.9, and 9.5%, the accuracy was 3.7, 7.1 and 6.3%, and within-runs precision (n=6) was 3.9, 2.9 and 5.1% for total plasma, non-protein bound plasma fraction and leukemic cells, respectively. The correlation coefficients (R2) were 1.00 for all calibration curves. These assays have been applied to analyze samples from one patient with acute myelogenous leukemia during 24 h after i.v. infusion of etoposide (100 mg/m2).
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Yin G, Liu Z, Zhou R, Zhan J, Wang J, Yuan N. Mass transport characteristics and chromatographic behavior of preparative electrochromatography on hydroxyapatite. J Chromatogr A 2001; 918:393-9. [PMID: 11407586 DOI: 10.1016/s0021-9673(01)00782-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Introducing an electric field into chromatography on hydroxyapatite (HAP) was attempted in order to enhance mass transfer and separation performance. A membrane spaced multicompartment electrolyzer was developed for electrochromatography on HAP. The high performance of liquid transport by electroosmotic flux was identified and described in terms of dynamic electroosmotic pressure. The application of the electric field resulted in an improved adsorption of bovine serum albumin as shown by the breakthrough curve as function of the electric field. An improved elution was also obtained in the presence of the electric field. The results show that electroosmosis is a powerful tool of liquid transport and dispersion in a packed bed of fine particles and has potential in the large-scale chromatography of biological molecules.
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Hill LI, Jin S, Zhou R, Venkataraman D, DiSalvo FJ. Synthesis and Characterization of Oxidized W6S8L6 Clusters. Inorg Chem 2001; 40:2660-5. [PMID: 11375676 DOI: 10.1021/ic001099d] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cationic [W(6)S(8)L(6)]PF(6) (L = PEt(3) (3), 4-tert-butylpyridine (4)) clusters were successfully synthesized and isolated for the first time by reacting the corresponding neutral W(6)S(8)L(6) (L = PEt(3) (1), 4-tert-butylpyridine (2)) clusters with [Cp(2)Fe]PF(6) as the oxidant. The products 3 and 4 were characterized by NMR spectroscopy, mass spectroscopy, and X-ray crystallography (only for 3) and shown to be the desired oxidized W(6)S(8) clusters with a metal electron count of 19. Magnetic property studies showed that they are paramagnetic compounds with S = (1)/(2). Their chemical properties and stability are also reported. Crystal data for 3.2 THF: space group, R3 (No. 148); a = 13.91170(10) A; c = 32.4106(2) A; Z = 3.
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