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Chaubal SA, Ferre LB, Molina JA, Faber DC, Bols PEJ, Rezamand P, Tian X, Yang X. Hormonal treatments for increasing the oocyte and embryo production in an OPU–IVP system. Theriogenology 2007; 67:719-28. [PMID: 17140652 DOI: 10.1016/j.theriogenology.2006.07.022] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2006] [Accepted: 07/24/2006] [Indexed: 11/26/2022]
Abstract
The objective was to enhance the inherent developmental ability of bovine oocytes retrieved by ultrasound-guided transvaginal aspiration. Various hormonal regimes were utilized to produce partially matured oocytes in vivo, in order to improve embryo development following IVF. In the first experiment, a two-by-two factorial design was used with FSH (multiple versus single dose) and im administration of LH (yes versus no) 6h prior to OPU. In all protocols (which lasted for nine consecutive weeks), ovarian stimulation was performed in the presence of a CIDR. One FSH administration was adequate for ovarian stimulation (9.33+/-0.7 and 10.14+/-0.7 follicles per cow per OPU session); however, multiple injections increased (P<0.05) follicular response (12.97+/-0.7 and 13.97+/-0.7). In the second experiment, a two-by-two factorial design was used to compare the effects, during ovarian stimulation, of the presence or absence of CIDR, and iv treatment with LH 6h prior to OPU (yes versus no), on oocyte competence (judged by blastocyst development rates following IVF). Presence of CIDR during superstimulation had no effect on the follicular response. Administration of LH 6h prior to OPU increased (P<0.05) the oocytes of higher morphological grades, and in the absence of a CIDR, improved (P<0.05) blastocyst development rate. Treatment with LH, 6h prior to OPU without the use of CIDR during ovarian stimulation, resulted in 2.89+/-0.4 blastocysts per cow per OPU session as compared to 1.56+/-0.4, 1.56+/-0.4 and 1.33+/-0.4 for all other groups. In conclusion, compared to single administration, multiple FSH administration increased (P<0.05) available follicles for aspiration. Moreover, when ovarian stimulation in the absence of CIDR was followed by administration of LH 6h prior to OPU, it increased (P<0.05) the number of blastocysts per OPU session.
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Affiliation(s)
- S A Chaubal
- Center for Regenerative Biology, University of Connecticut, 1392 Storrs Road, Storrs, CT 06269-4243, USA
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202
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Zhang Z, Tian X. Single-trial extraction of cognitive evoked potentials by combination of third-order correlation and wavelet denoising. Conf Proc IEEE Eng Med Biol Soc 2007; 2005:2029-32. [PMID: 17282624 DOI: 10.1109/iembs.2005.1616855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The application of a recently proposed denoising implementation for obtaining cognitive evoked potentials (CEPs) at the single-trial level is shown. The aim of this investigation is to develop the technique of extracting CEPs by combining both the third-order correlation and the wavelet denoising methods. First, the noisy CEPs was passed through a finite impulse response filter whose impulse response is matched with the shape of the noise-free signal. It was shown that it is possible to estimate the filter impulse response on basis of a select third-order correlation slice (TOCS) of the input noisy CEPs. Second, the output from the third-order correlation filter is decomposed with bi-orthogonal splines at 5 levels. The CEPs is reconstructed by wavelet final approximation a<inf>5</inf>. We study its performance in simulated data as well as in cognitive evoked potentials of normal rat and Alzheimer's disease (AD) model rat. For the simulated data, the method gives a significantly better reconstruction of the single-trial cognitive evoked potentials responses in comparison with the simulated data. Moreover, with this approach we obtain a significantly better estimation of the amplitudes and latencies of the simulated CEPs. For the real data, the method clearly improves the visualization of single-trial CEPs. This allows the calculation of better averages as well as the study of systematic or unsystematic variations between trials.
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Affiliation(s)
- Z Zhang
- Department of Biomedical Engineering, Tianjin Medical University, Tianjin, 300070, China
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203
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Tian X, Geng X. Chaotic Dynamics in Tracing BAEP and its Application on Investigating Brainstem Malfunction. Conf Proc IEEE Eng Med Biol Soc 2007; 2005:3616-9. [PMID: 17281009 DOI: 10.1109/iembs.2005.1617264] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The purpose of this study is to investigate the chaotic dynamics of tracing (dynamic) brainstem auditory evoked potential (BAEP), then to investigate the brainstem malfunction via dynamic characteristics of tracing BAEP. The radial basis function neural network (RBFNN) technique in combination with the moving window average (MWA) method was employed in order to extract the tracing BAEP from strong noise background. Data of noisy BAEP were collected from the Infantile spasm (IS) group with brainstem malfunction and the tester group respectively. The chaotic dynamics of tracing BAEP were analyzed using phase projection and correlation dimension techniques. The results of this study have demonstrated: (1) there is a much stronger determination in BAEP than in noisy BAEP shown by more deterministic phase projections and lower D<inf>2</inf>in BAEP; (2) trajectories of BAEP never repeat and the value of correlation dimension is fractal; (3) the phase projection of BAEP for brainstem malfunction group shows more chaotic and has higher D<inf>2</inf>than those for the tester group. The conclusions of this investigation suggest that BAEP is chaotic not deterministic and there is rich dynamics in BAEP; tracing BAEP is much more useful than noisy BAEP in describing brainstem malfunction because BAEP shows determination corresponding to brainstem function; BAEP in brainstem malfunction has more non-order dynamics than that in the tester.
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Affiliation(s)
- X Tian
- Department of Biomedical Engineering, Tianjin Medical University, Tianjin, 300070, China
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204
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Liu T, Tian X. A Simulation Study of Firing Patterns based on Coupling Effect between Soma and Dendrite. Conf Proc IEEE Eng Med Biol Soc 2007; 2005:3624-7. [PMID: 17281011 DOI: 10.1109/iembs.2005.1617266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The aim of this study is to investigate how firing patterns of neuron in hippocampus change with coupling effect between soma and dendrite via simulation of single neuron firings by a two-compartment (soma-dendrite) model. The results will help to understand how firing patterns relative to synaptic plasticity in further study. The neuron model used in this study consisted two compartments: the soma compartment and the dendrite compartment, which can describe synaptic input functions. Simulations of neural firings were performed with fourth order Runge-Kutta algorithm with different range of coupling conductance. Firing patterns of neuron were simulated under different current applied to soma (Is). The range for different firing patterns is: Is=0..A/cm2, range for spiking is [0.0, 1.8] and [4.5, ..], for bursting is [1.9,4.4]; Is=0.5..A/cm2, range for spiking is [0.0, 2.2] and [4.0, ..], for bursting is [2.3,3.9]; Is=1.0..A/cm2, range for spiking is [0.0, 2.5] and [3.6, ..], for bursting is [2.6,3.5]; Is=1.5..A/cm2, range for spiking is [0.0, 2.5] and [3.8, ..], for bursting is [2.6,3.7]; Is=2.0..A/cm2, range for spiking is [0.0, 2.6] and [3.6, ..], for bursting is [2.7,3.5]; Is=2.5..A/cm2, range for spiking is [0.0, 2.6] and [3.3, ..], for bursting is [2.7,3.2].
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Affiliation(s)
- T Liu
- Department of Biomedical Engineering, Tianjin Medical University, Tianjin, China, 300070
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205
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Kubota C, Kojima T, Nagai T, Tian X, Yang X. 346 BOVINE EMBRYO DEVELOPMENT AFTER IVM/IVF/IVC OF OOCYTES STORED FOR 22 H IN VARIOUS MEDIA. Reprod Fertil Dev 2007. [DOI: 10.1071/rdv19n1ab346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The timing of IVM–IVF–IVC is restricted by the onset of oocyte maturation, and sometimes oocytes must be treated at midnight. If we could regulate the timing of IVM of oocytes without decreasing their developmental competence, the IVM–IVF–IVC system could be a more applied technology. The present study was performed to examine the effects of in vitro storage of bovine oocytes in simple media prior to maturation culture to manipulate the start of IVM. Bovine follicular fluid (bFF), Dulbecco's PBS (PBS), M199 Earle salts (M199), and Earle salts supplemented with 5 mM NaHCO3 (M199A) were used as the fundamental media, after an addition of antibiotics, for in vitro storage of bovine cumulus–oocyte complexes (COCs) collected from ovaries obtained at the slaughterhouse. The fundamental media except for bFF were supplemented with 10% fetal bovine serum (FBS) or 1 mg mL−1 polyvinyl alcohol (PVA). COCs were collected from follicles (3–8 mm in diameter) and washed twice in each medium; then approximately 50 COCs were submerged in 1 mL of each medium in cryotubes (Falcon #2812, 2.5 mL; Becton Dickinson Labware, Lincoln, NJ, USA), which were stored in a container kept at 38.5°C for 22 h under air-closed condition (in vitro storage: IVS). Subsequently, the stored COCs were in vitro-matured (IVM) for 22 h in M199 with 10% FBS and 20 µg mL−1 estradiol, fertilized (IVF), and cultured in CR1aa (IVC) for examination of their development to the blastocyst stage (Kubota et al. 1998 Mol. Reprod. Dev. 51, 281–286). Fresh oocytes without IVS were used as controls. The nuclear status of oocytes after IVS–IVM was compared to that of control oocytes by aceto-orcein stain. Their developmental rates to the blastocyst stage after IVM–IVF–IVC were compared between experimental and control groups. The experiment was repeated more than 3 times, and results were statistically analyzed using Student's t-test. When bFF and PBS supplemented with FBS or PVA were used for IVS, the rates of survived COCs after IVS and the development to the blastocyst stage after IVM–IVF–IVC (bFF (n = 87): 0%, 0%; PBS/FBS (n = 72): 84%, 1%; and PBS/PVA (n = 81): 89%, 6%, respectively) were significantly lower than those of the control group (n = 406; 97% and 29%, respectively). On the other hand, when M199A supplemented with FBS or PVA was used for IVS, the survival rate after IVS and the developmental rate to the blastocyst stage after IVS–IVM–IVF (M199A/FBS (n = 97): 82%, 28%; and M199A/PVA (n = 111): 98%, 31%, respectively) did not differ from those of the control group. After IVS, cumulus expansion was not seen and most of the oocyte nuclei reached the GVBD stage. These results suggest that the nuclear maturation progress of bovine oocytes can be regulated for at least 22 h in M199A without any deleterious influence on the number of oocytes surviving at an immature state after the storage and their subsequent development to the blastocyst stage after IVM–IVF–IVC. The delayed maturation allows a flexible fertilization schedule which is advantageous in research and industrial applications.
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206
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Xu J, Sung LY, Zhang J, Tian X, Chen YE, Yang X, Du F. 96 TRICHOSTATIN A IMPROVED THE QUALITY OF RABBIT NUCLEAR TRANSFER EMBRYOS. Reprod Fertil Dev 2007. [DOI: 10.1071/rdv19n1ab96] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Nuclear reprogramming is dependent upon a number of factors, including chromatin organization and modification. Trychostatin A (TSA), a histone deacetylase inhibitor, was used to increase histone acetylation and to improve reprogrammability in both cattle and mice. The objective of the study was to determine whether TSA could improve the pre-implantational development potential of rabbit nuclear transplant (NT) embryos. Rabbit oocytes were flushed from the oviducts of superovulated donors treated with the regime of FSH and hCG. Cumulus cells were then denuded from the oocytes by incubation in 0.5% hyaluronidase and pipetting. Oocyte enucleation was conducted in 10% FBS M199 and confirmed under fluorescence microscopy. Cumulus cells were prepared as nuclear donors for NT; a donor cell with the diameter approximately 15–19 µm was transferred into the perivitelline space of an enucleated oocyte, and subsequently fused with the oocyte recipient by application of 3 direct current pulses at 3.2 kV cm−1 for a duration of 20 µs/pulse. Fused embryos were activated by the same electrical stimulation regime described above, and subsequently cultured in M199 + 10% FBS containing 2.0 mM 6-dimethylaminopurine (DMAP) and 5 µg mL−1 cycloheximide for 1 h. Rabbit NT embryos were cultured in 5 nM TSA-2.5% FBS-B2 medium for 10 h before being transferred into regular medium (FBS-B2). The TSA-treated embryos (5 nM vs. 0 nM) were cultured in 400 µL FBS-B2 medium for 5 days in 5% CO2 in a humidified atmosphere at 38.5°C (initiation of activation = Day 0). NT embryo development to cleaved (2 to 4 cell), morula, and blastocyst stages was evaluated on Day 2, Day 3, and Day 5, respectively. The selected NT blastocysts were counted for cell numbers following Hoechst 33342 epifluorescenin staining. The results (Table 1) showed that there was no difference on pre-implantational development of cloned embryos between TSA-added and control groups (P > 0.05). However, a significantly higher cell number per NT blastocyst was found in the TSA-added group (357 vs. 113; P < 0.05). This indicated that the blastocyst quality in NT embryos was improved with the addition of TSA by increasing histone acetylation activity. The developmental potential of TSA-treated NT embryos to term is under investigation.
Table 1.Effects of TSA on the pre-implantational development of cloned rabbit embryos
This work was supported by NIH/NCRR-SBIR grant: 1R43RR020261-01.
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207
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Ma L, Huang Y, Song Z, Feng S, Tian X, Du W, Qiu X, Heese K, Wu M. Livin promotes Smac/DIABLO degradation by ubiquitin-proteasome pathway. Cell Death Differ 2006; 13:2079-88. [PMID: 16729033 DOI: 10.1038/sj.cdd.4401959] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Livin, a member of the inhibitor of apoptosis protein (IAP) family, encodes a protein containing a single baculoviral IAP repeat (BIR) domain and a COOH-terminal RING finger domain. It has been reported that Livin directly interacts with caspase-3 and -7 in vitro and caspase-9 in vivo via its BIR domain and is negatively regulated by Smac/DIABLO. Nonetheless, the detailed mechanism underlying its antiapoptotic function has not yet been fully characterized. In this report, we provide, for the first time, the evidence that Livin can act as an E3 ubiquitin ligase for targeting the degradation of Smac/DIABLO. Both BIR domain and RING finger domain of Livin are required for this degradation in vitro and in vivo. We also demonstrate that Livin is an unstable protein with a half-life of less than 4 h in living cells. The RING domain of Livin promotes its auto-ubiquitination, whereas the BIR domain is likely to display degradation-inhibitory activity. Mutation in the Livin BIR domain greatly enhances its instability and nullifies its binding to Smac/DIABLO, resulting in a reduced antiapoptosis inhibition. Our findings provide a novel function of Livin: it exhibits E3 ubiquitin ligase activity to degrade the pivotal apoptotic regulator Smac/DIABLO through the ubiquitin-proteasome pathway.
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Affiliation(s)
- L Ma
- Hefei National Laboratory for Physical Sciences at Microscale and School of Life Sciences, University of Science and Technology of China, Hefei, Anhui 230027, People's Republic of China
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208
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Chaubal SA, Molina JA, Ohlrichs CL, Ferre LB, Faber DC, Bols PEJ, Riesen JW, Tian X, Yang X. Comparison of different transvaginal ovum pick-up protocols to optimise oocyte retrieval and embryo production over a 10-week period in cows. Theriogenology 2006; 65:1631-48. [PMID: 16243385 DOI: 10.1016/j.theriogenology.2005.07.020] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Accepted: 07/12/2005] [Indexed: 11/22/2022]
Abstract
The objective was to develop a simple and effective ovum pick-up (OPU) protocol for cows, optimised for oocyte harvest and subsequent in vitro embryo production (IVP). Five protocols differing in collection frequency, dominant follicle removal (DFR) and FSH stimulation were tested on groups of three cows each, over an interval of 10 consecutive weeks. Performance was evaluated on per OPU session, per week and pooled (3 cowsx10weeks) basis. Among the non-stimulated groups, on a per cow per session basis, once- or twice-weekly OPU had no effect on the mean (+/- S.E.M.) number of follicles aspirated, oocytes retrieved and blastocysts produced (0.6+/-0.8 and 0.7 +/- 0.7, respectively). However, DFR 72 h prior to OPU almost doubled blastocyst production (1.2 +/- 1.3). In stimulated groups, FSH treatment (80 mg IM and 120 mg SC) was given once weekly prior to OPU. Treatment with FSH, followed by twice-weekly OPU, failed to show any synergistic effect of FSH and increased aspiration frequency. When FSH was given 36 h after DFR, followed by OPU 48 h later, more (P < 0.05) follicles (16.0 +/- 5.0), oocytes (10.6 +/- 4.5) and embryos (2.1 +/- 1.2) were obtained during each session, but not on a weekly basis. Pooled results over 10 weeks showed an overall improved performance for the treatment groups with twice-weekly OPU sessions, due to double the number of OPU sessions performed. However, the protocol that consisted of DFR, FSH treatment and a subsequent single OPU per week, was the most productive and cost-effective, with potential commercial appeal.
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Affiliation(s)
- S A Chaubal
- Center for Regenerative Biology/Department of Animal Science, University of Connecticut, 1392 Storrs Rd., Storrs, CT 06269-4243, USA
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209
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Tang M, Tian X, Shum P, Fu S, Dong H, Gong Y. Four-wave mixing assisted self-stable 4x10 GHz actively mode-locked Erbium fiber ring laser. Opt Express 2006; 14:1726-1730. [PMID: 19503500 DOI: 10.1364/oe.14.001726] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We proposed and developed a self-stable multiwavelength (4 cbannels) 10-GHz actively mode-locked Erbium-doped fiber ring laser with 0.8 nm wavelength spacing. A 1-km highly nonlinear fiber is incorporated in the laser cavity to eliminate the strong gain competitions in the homogeneously broadened EDF by multiple parametric four-wave mixing processes. The fiber nonlinearity is also helpful to provide phase locking and stabilize the output pulse. Stable laser pulses at 1556.55, 1557.36, 1558.17, and 1558.98 nm are successfully obtained simultaneously with supermode noise suppression ratio greater than 50 dB. The corresponding time-bandwidth products of four channels are 0.39 ~ 0.41.
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210
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Kim A, Russell H, Raman J, Gupta M, Tian X, Lang R, Miller J. Cardiomyopathy Results in Dysregulation of Endocardial Thrombomodulin and An Altered Protein C Activation Pathway. J Investig Med 2006. [DOI: 10.1177/108155890605402s26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- A.Y. Kim
- The University of Chicago, Chicago, IL
| | | | - J. Raman
- The University of Chicago, Chicago, IL
| | - M. Gupta
- The University of Chicago, Chicago, IL
| | - X. Tian
- The University of Chicago, Chicago, IL
| | - R.M. Lang
- The University of Chicago, Chicago, IL
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211
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Kim AY, Russell HM, Raman J, Gupta M, Tian X, Lang RM, Miller JL. 26 CARDIOMYOPATHY RESULTS IN DYSREGULATION OF ENDOCARDIAL THROMBOMODULIN AND AN ALTERED PROTEIN C ACTIVATION PATHWAY. J Investig Med 2006. [DOI: 10.2310/6650.2005.x0015.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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212
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Burmeister MA, Lazartigues E, Tian X, Kutschke W, Sharma RV, Kapusta DR, Davisson RL. Virally expressed siRNA mediates localized gene silencing in specific cardiovascular (CV) regulatory nuclei of mouse brain. FASEB J 2006. [DOI: 10.1096/fasebj.20.4.a364-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Melissa A Burmeister
- Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences Center1901 Perdido StreetNew OrleansLA70112
- Anatomy and Cell BiologyThe University of Iowa Carver College of Medicine1–251 Bowen Science BuildingIowa CityIA52242
| | - E. Lazartigues
- Anatomy and Cell BiologyThe University of Iowa Carver College of Medicine1–251 Bowen Science BuildingIowa CityIA52242
| | - X. Tian
- Anatomy and Cell BiologyThe University of Iowa Carver College of Medicine1–251 Bowen Science BuildingIowa CityIA52242
| | - W. Kutschke
- Anatomy and Cell BiologyThe University of Iowa Carver College of Medicine1–251 Bowen Science BuildingIowa CityIA52242
| | - R. V. Sharma
- Anatomy and Cell BiologyThe University of Iowa Carver College of Medicine1–251 Bowen Science BuildingIowa CityIA52242
| | - D. R. Kapusta
- Pharmacology and Experimental TherapeuticsLouisiana State University Health Sciences Center1901 Perdido StreetNew OrleansLA70112
| | - R. L. Davisson
- Anatomy and Cell BiologyThe University of Iowa Carver College of Medicine1–251 Bowen Science BuildingIowa CityIA52242
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213
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Du F, Xu J, Gao S, Sung LY, Stone D, Joyner M, Zhang J, Chaubal S, Tian X, Chen YE, Yang X. 31 FULL-TERM AND LIVE RABBIT CLONES PRODUCED BY SOMATIC CELL NUCLEAR TRANSFER. Reprod Fertil Dev 2006. [DOI: 10.1071/rdv18n2ab31] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Transgenic/knockout (KO) rabbits can serve as an excellent animal model for human cardiovascular diseases (CVD) and other diseases. However, the production of transgenic/KO rabbits is hindered by low efficiency of traditional DNA microinjection and the unavailability of embryonic stem cell lines. An alternative approach is to produce transgenic/KO rabbits by somatic cell nuclear transfer (SCNT) using genetically modified somatic cells as nuclear donors. Our initial objective of the study was to prove the feasibility of cloning rabbits by SCNT because rabbit is a difficult species to be cloned. Rabbit oocytes were flushed from the oviducts of superovulated donors treated with the regime of follicle-stimulating hormone (FSH) and human choriani gonadotropin (hCG). Cumulus cells were then denuded from the oocytes by incubation in 0.5% hyaluronidase and pipetting. Oocyte enucleation was conducted in M199 + 10% fetal bovine serum (FBS) and confirmed by fluorescence microscopy. Cumulus cells used for nuclear donors were prepared from fresh cumulus-oocytes complexes. The donor nucleus was transferred into a recipient oocyte by either cell fusion or direct nuclear injection method. In the cell fusion method, a small donor cell with the diameter approximately 15–19 µm was transferred into the perivitelline space of an enucleated oocyte; subsequently the somatic cell-cytoplast pair was fused by applying three direct current pulses at 3.2 kV/cm for a duration of 20 µs/pulse. In the direct nuclear injection method, a mechanically lysed donor cell was injected into oocyte cytoplasm with the aid of a piezo-drill system. Fused embryos or injected oocytes were activated by the same electrical stimulation regime described above, and subsequently cultured in M199 + 10% FBS containing 2.0 mM 6-dimethylaminopurine (DMAP) and 5 µg/mL cycloheximide for 2 h. For the in vitro study, cloned embryos were cultured in B2 medium plus 2.5% FBS for 5 days (initiation of activation = day 0) at 38.5°C in 5% CO2 humidified air. For the in vivo study, cloned embryos were cultured for 20–22 h in vitro before transfer into pseudopregnant rabbit recipients. Pregnancy was monitored by palpation and/or ultrasound on Days 14–16 post embryo transfer (ET). The results (Table 1) show that the donor nuclei-introducing rate was higher with nuclear direct injection than with the cell fusion method (P < 0.05). There were no significant differences among subsequent cleavage and development to morula and blastocysts between both methods, although the development rates of cloned embryos via electrically mediated fusion were higher than those derived from the injection group. One recipient in the injection group (1/6, 17%) and six recipients in the fusion group (6/16, 38%) were diagnosed as pregnant. From the fusion group, one full-term but stillborn and one live and healthy clone rabbit were delivered on Days 33 and 31 post-ET, respectively. To our knowledge, this is the second report of full term development of cloned rabbit by somatic nuclear transfer cloning. Our further study is to clone live rabbit offspring with modified transgenic/KO somatic cell lines.
Table 1.
In vitro development of rabbit cloned embryos with cumulus cells as nuclear donors
This work was supported by NIH/NCRR-SBIR grant: 1R43RR020261–11.
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214
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Li C, Deng D, Jing D, Love W, Kratzmeier M, Bek F, Tian X, Romeo R, Mueller O, Superko R. Th-P17:429 A rapid microfluidic assay for HDL-C and HDL subclass distribution. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)82387-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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215
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Li C, Deng D, Jing D, Romeo R, Kratzmeier M, Bek F, Tian X, Mueller O, Schreiber D, Sussman H. Th-P17:430 Coronary risk assessment using a rapid microfluidic lipoprotein assay. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)82388-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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216
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Tian X, Aruva MR, Wolfe HR, Qin W, Sauter ER, Thakur ML, Waldman SA, Wickstrom E. Tumor-targeting peptide-PNA-peptide chimeras for imaging overexpressed oncogene mRNAs. Nucleosides Nucleotides Nucleic Acids 2005; 24:1085-91. [PMID: 16248097 DOI: 10.1081/ncn-200059177] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We have optimized a method involving continuous solid phase synthesis of chelator-peptide-PNA-peptide probes in order to noninvasively image oncogene mRNAs overexpressed in tumors. The PNA (peptide nucleic acid) probes carry cyclized peptide ligand analogs specific for receptors overexpressed on malignant breast or colorectal cancer cells, and chelators to bind radioactive metal ions, or a fluorophore. In vivo scintigraphic imaging of MCF7 xenografts in immunocompromised mice indicated that CCND1 and MYC [99sTc] chelator-PNA-D (CSKC) probes concentrated in MCF7 cells up to 7 times more than the corresponding mismatch controls.
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Affiliation(s)
- X Tian
- Biochemistry and Molecular Pharmacology, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
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217
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Cai H, Yu DH, Tian X, Zhu YX. Coadministration of Interleukin 2 Plasmid DNA with Combined DNA Vaccines Significantly Enhances the Protective Efficacy AgainstMycobacterium tuberculosis. DNA Cell Biol 2005; 24:605-13. [PMID: 16225391 DOI: 10.1089/dna.2005.24.605] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Coadministration of interleukin 2(IL-2) plasmid DNA with combined DNA vaccines enhanced Th1-type cellular responses by producing higher amounts of IFN-gamma with a higher ratio of antigen-specific IgG2a/IgG1. The IFN-gamma specific for Ag85B, MPT64, and MPT83 in this group was 415, 267, and 255 U/ml, respectively, and was 1.6-, 1.8-, and 2.5-fold higher than that of the same vaccine without adding IL-2. The IgG2a/IgG1 ratio for Ag85B, MPT64, and MPT83 was 4, 8, and 4, respectively, upon addition of the genetic adjuvant in the DNA vaccine, which was four times higher for every antigen when IL-2 was not included. Fluorescence activated cell sorter (FACS) analysis showed that, in the presence of IL-2, CD8+ and CD4+ T cells increased significantly, whereas in the absence of the genetic adjuvant, only a mild increase was observed for CD8+ T cells compared to the vector DNA-treated group. Bacterial CFU was reduced to less than 1/100 in the lung and to about 1/10 in the spleen relative to the same combined DNA vaccine without IL-2. The lungs of this group of mice showed much less damage due to an influx of epithelioid macrophages and less lymphocytes. RT-PCR showed that antigen genes could be detected in more organs and for a longer period of time when treated with combined DNA vaccine formulated in IL-2. We suggest that IL-2 enhanced the immunigencity and protective efficacy in immunized mice by improving the Th1-type response and also by prolonging the antigen gene expression in different organs.
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Affiliation(s)
- H Cai
- The National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking University, Beijing, People's Republic of China.
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218
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Cai H, Hu XD, Yu DH, Li SX, Tian X, Zhu YX. Combined DNA vaccine encapsulated in microspheres enhanced protection efficacy against Mycobacterium tuberculosis infection of mice. Vaccine 2005; 23:4167-74. [PMID: 15908060 DOI: 10.1016/j.vaccine.2005.03.024] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2004] [Revised: 12/16/2004] [Accepted: 03/07/2005] [Indexed: 10/25/2022]
Abstract
In a study to develop novel vaccination strategies against tuberculosis, we encapsulated DNA encoding Ag85B, MPT-64 and MPT-83 antigens mixed with dimethyldioctyldecyl ammonium bromide (DDA) into biodegradable poly(dl-lactide-co-glycolide, PLGA) microspheres. Scanning electron microscopy (SEM) analysis demonstrated a uniform microsphere population with a mean diameter of <5microm. Using RT-PCR we were able to demonstrate antigen gene expression in selected tissue. Moreover, in mice injected with PLGA encapsulated DNA, the levels of expression appeared to be higher comparing to those injected with non-encapsulated DNA. Also, C57BL/6 mice immunized with a single dose of PLGA encapsulated DNA produced increased levels of IFN-gamma in the supernatant of spleen cells when cultured in the presence of the recombinant antigens. High levels of specific IgG antibody against the three antigens were also observed. In vaccine/challenge experiments, mice receiving a single dose of PLGA encapsulated DNA were protected against Mycobacterium tuberculosis challenge at levels comparable to groups of mice immunized with three doses of non-encapsulated DNA vaccine or with Mycobacterium bovis BCG.
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Affiliation(s)
- H Cai
- National Laboratory of Protein Engineering and Plant Genetic Engineering, College of Life Sciences, Peking University, Beijing 100871, China.
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219
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Abstract
Information theory is used to analyze the character of signal peptide quantitatively, especially residents. On the basis of the above analysis, a method named simplified information-matrix has been developed to predict the cleavage sites of signal peptides. A comparison between the results of weight-matrix and simplified information-matrix is presented.
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Affiliation(s)
- L Liu
- 2002 Master, Department of physics, School of Science, Tianjin University, P. R. China.
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220
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Cai H, Tian X, Hu XD, Li SX, Yu DH, Zhu YX. Combined DNA vaccines formulated either in DDA or in saline protect cattle from Mycobacterium bovis infection. Vaccine 2005; 23:3887-95. [PMID: 15917109 DOI: 10.1016/j.vaccine.2005.03.025] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2005] [Revised: 03/23/2005] [Accepted: 03/26/2005] [Indexed: 11/20/2022]
Abstract
We tested the effectiveness of combined DNA vaccines encoding antigens Ag85B, MPT64 and MPT83 from Mycobacterium tuberculosis on cattle. Our results showed that calves treated with combined DNA vaccines in the presence of dimethyldioctyldecyl ammonium bromide (DDA) or saline elicited a strong gamma interferon (IFN-gamma) response 1 or 2 months after the third vaccination. All three antigens induced substantial levels of IFN-gamma production 1 month after the bacterial challenge, when the BCG-driven IFN-gamma levels dropped to less than one third of their peak values. Animals receiving combined DNA vaccines produced highest amounts of IgG antibody titer 2 months after the third vaccination. Steady state low IgG levels were found 2 months after bacterial challenge. A few small lung and lymph node lesions were detected in 1/5 animals treated with combined DNA vaccines, whereas 3/5 of BCG-treated and 5/5 of vector-control calves showed larger and significantly more lesions. About 70- to 100-fold fewer bacteria were found in the lungs and lymph nodes of combined DNA vaccine-treated animals compared to those of the control group. Histopathological analyses showed that vaccinated calves possessed substantially improved post-infection lung and lymph node pathology relative to the controls. Our data indicate that combined DNA vaccines may be used in cattle to combat bovine tuberculosis.
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Affiliation(s)
- H Cai
- National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking University, Beijing 100871, China.
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221
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Wickstrom E, Choob M, Urtishak KA, Tian X, Sternheim N, Talbot S, Archdeacon J, Efimov VA, Farber SA. Sequence specificity of alternating hydroyprolyl/phosphono peptide nucleic acids against zebrafish embryo mRNAs. J Drug Target 2005; 12:363-72. [PMID: 15545086 DOI: 10.1080/10611860412331285242] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Morpholino phosphorodiamidate (MO) DNA mimics display excellent water solubility and hybridization properties toward DNA and RNA, and have been utilized in the model vertebrate zebrafish (Danio rerio) for genome-wide, sequence-based, reverse genetic screens during embryonic development. Peptide nucleic acids (PNAs) exhibit excellent mismatch discrimination, nuclease resistance, and protease resistance, but low solubility. Negatively charged DNA mimics composed of alternating residues of trans-4-hydroxy-L-proline peptide nucleic acid monomers and phosphono peptide nucleic acid monomers (HypNA-pPNA) combine all of the positive features of both MOs and PNAs. Thus, we evaluated PNA oligomers and HypNA-pPNA oligomers as an alternative to MOs for oligonucleotide inhibition of gene expression in zebrafish embryos. We observed that HypNA-pPNA 18-mers displayed comparable potency to MO 25-mers as knockdown agents against chordin, notail and uroD, with greater mismatch stringency. Furthermore, we observed that a specific HypNA-pPNA 18-mer elicited the dharma (bozozok)(-/-) phenotype in zebrafish embryos, which MO 25-mers do not. These observations validate HypNA-pPNAs as an alternative to MO oligomers for reverse genetic studies. The stronger hybridization and greater specificity of HypNA-pPNAs enable knockdown of mRNAs unaffected by MO oligomers.
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Affiliation(s)
- E Wickstrom
- Department of Biochemistry and Molecular Pharmacology, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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222
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Tanimoto H, Shigemasa K, Tian X, Gu L, Beard JB, Sawasaki T, O'Brien TJ. Transmembrane serine protease TADG-15 (ST14/Matriptase/MT-SP1): expression and prognostic value in ovarian cancer. Br J Cancer 2005; 92:278-83. [PMID: 15611789 PMCID: PMC2361855 DOI: 10.1038/sj.bjc.6602320] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Tumour-associated differentially expressed gene-15 (TADG-15/ST14/matriptase/MT-SP1) is a novel member of the transmembrane serine proteases. Previous studies indicated that TADG-15 is overexpressed in ovarian tumours; however, relationships between expression of TADG-15 and clinical characteristics of ovarian cancer remain unclear. The purpose of this study was to examine TADG-15 expression in ovarian cancers and determine any associations with clinicopathological characteristics or patient survival. Immunohistochemical study revealed that TADG-15 was expressed in 50 (56.2%) of 89 ovarian carcinomas, whereas it was not detected in normal ovaries. TADG-15 expression was significantly more common in patients with early stage disease compared with patients with advanced stage diseases (namely, stage I, 24 out of 33: 72.7%; stage II/III/IV, 26 out of 56: 46.4%; P=0.0157). Kaplan–Meier survival curves demonstrated that patients with TADG-15-positive tumours have had substantially longer survival (P=0.0480). The mean value of relative TADG-15 mRNA expression ratio was significantly higher in stage I tumours than in stage II/III/IV tumours (P=0.0053). Increased expression of TADG-15 is frequently detected in early stage cancers, with expression level downregulated during progression of disease. TADG-15 is associated with early stage ovarian cancer and longer patient survival; therefore, it may be a favourable prognostic marker for this malignancy.
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Affiliation(s)
- H Tanimoto
- Department of Gynecology, Higashi-Hiroshima Medical Center, Higashi-Hiroshima, Japan
| | - K Shigemasa
- Department of Obstetrics and Gynecology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3, Kasumi, Minami-Ku, Hiroshima 734-8551, Japan
- Department of Obstetrics and Gynecology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3, Kasumi, Minami-Ku, Hiroshima 734-8551, Japan. E-mail:
| | - X Tian
- Department of Obstetrics and Gynecology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3, Kasumi, Minami-Ku, Hiroshima 734-8551, Japan
| | - L Gu
- Department of Obstetrics and Gynecology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3, Kasumi, Minami-Ku, Hiroshima 734-8551, Japan
| | - J B Beard
- Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - T Sawasaki
- Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - T J O'Brien
- Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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Abstract
This study evaluated the adjuvant Dimethyldioctyldecyl Ammonium Bromide (DDA) effect on the protective immunity induced by a combination of plasmids containing genes encoding antigens Ag85B, MPT-83, and ESAT-6 from Mycobacterium tuberculosis. The combined DNA vaccines in DDA resulted in significant increases in both specific IgG and splenic T-cell-derived Th1-type cytokine gamma interferon (IFN-gamma) production in response to the three purified antigens when compared to that of combined DNA vaccines in saline. Vaccines in DDA increased the protective efficacy of mice challenged with M. tuberculosis H37Rv as measured by reduced relative CFU counts in their lungs. Mice immunized with the combined DNA vaccines were shown to limit the growth of tubercle bacilli both in lungs and in spleens. Histopathological analyses showed that vaccinated mice had substantially improved postinfection lung pathology relative to the controls. We suggest that our combination of antigens together with DDA formulation may provide a new insight into tuberculosis prevention.
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Affiliation(s)
- H Cai
- The National Laboratory of Protein Engineering and Plant Genetic Engineering, Peking University, Beijing People's Republic of China
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225
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Chaubal S, Molina J, Olrichs C, Ferré L, Faber D, Tian X, Yang X. 261DIFFERENT TRANSVAGINAL OVUM PICK-UP STRATEGIES TO OPTIMIZE THE OOCYTE
RETRIEVAL AND EMBRYO PRODUCTION OVER A FIXED PERIOD OF TIME. Reprod Fertil Dev 2004. [DOI: 10.1071/rdv16n1ab261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The objective of this study was to compare the efficacy of different oocyte retrieval schemes over a period of 10 weeks. Fifteen multiparous Angus cows were randomly assigned (n=3/group) to the following groups: 1) OPU once/week (7-day interval), 2) OPU twice/week (3- and 4-day interval, alternately), 3) Dominant follicle removal (DFR)+OPU once/week. DFR followed by OPU 72h later, 4) DFR+FSH+OPU once/week. DFR followed 36h later by FSH (Folltropin, Bioniche, Belleville, Ontario, Canada) (120mg s.c. and 80mg i.m. administered simultaneously) followed by OPU 48h later, 5) FSH+OPU twice/week. FSH followed by OPU1 30h later and OPU2 96h after OPU1. The interval between OPU2 and next FSH was approximately 42h. The follicles were aspirated using an Aloka ultrasound scanner (Wallingford, CT, USA) and a 5-MHz probe. The COCs were selected based on morphology and matured in TCM-199, supplemented with 10% FCS, 0.01 unitsmL−1 bFSH, 0.01 unitsmL−1 bLH and antibiotics. Fertilization (Day 0) was carried out with TALP-FERT medium containing capacitation factors. Frozen semen from the same bull was used (1×106mL−1) throughout. After 18h the presumptive zygotes were cultured in SOF with 5% FCS (Holm P et al., 1999 Theriogenology 52, 683–700). The embryos were evaluated based on IETS guidelines (Grades 1 and 2 selected). The data were analyzed by chi-square test and ANOVA. In all parameters, the DFR followed by FSH and subsequent OPU once/week protocol gave the best results on a per-cow-per-week as well as total (3 cows over 10 weeks) basis. Though OPU was done only once/week, this group produced more total oocytes (303) than groups where OPU was done twice/week, either with FSH (286) or without FSH (229) and also produced more total embryos on Day 8 (71 blastocysts, 23.4% of oocytes cultured) than the latter two groups (64, 22.4% and 49, 21.4%, respectively). Among the nonstimulated groups, the OPU twice/week group had more total oocytes (236) than groups with OPU once/week, either without DFR (137) or with preceding DFR (160). However, a preceding DFR seemed to have a positive effect on oocyte quality as this group had a better embryo development rate (26.9%), producing more total embryos (42). In comparison, OPU twice/week produced total 49 embryos (21.4%) and OPU once/week produced 26 (19.4%). In conclusion, DFR coupled with single-shot FSH administration can be used effectively over a period of at least 10 consecutive weeks and can increase (P<0.05) the oocyte yield by two-fold and embryo production following IVF by two and half-fold, as compared to routine OPU-IVF done once a week.
Table 1
Per cow per week performance
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226
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Abstract
Imaging oncogene mRNA in tumours would provide a powerful tool for the early detection of occult malignant lesions. The goal was to prepare a chimera consisting of a dodecamer antisense peptide nucleic acid (PNA) specific for c-MYC oncogene overexpressed in human breast cancer cells and a chelating moiety that facilitates quantitative radiolabelling with 99mTc and evaluate it for hybridization and tissue distribution in laboratory animals. The pentapeptide chelator-PNA dodecamer specific for c-MYC mRNA was extended from a solid support by 9-fluorenylmethyloxycarbonyl (Fmoc) coupling. Similarly, a chelator-PNA chimera with four central mismatches was also prepared which served as a control. The chimeras were purified, characterized and evaluated for hybridization to c-MYC mRNA by fluorescent, real-time polymerase chain reaction (RT-PCR). The chimeras were labelled with 99mTc and their tissue distribution was examined in athymic nude mice bearing experimental human breast tumours. 99mTc radiolabelling was quantitative and presented a single peak in reversed phase liquid chromatography. Fluorescent real-time polymerase chain reactions using primer and fluorescent probe sets previously calculated for c-MYC mRNA demonstrated inhibition of reverse transcription by the c-MYC specific chimera as compared to that of the control. Tissue distribution studies of antisense and mismatch chimeras at 4 h and 24 h after administration displayed modest accumulation in the liver, and appreciable levels in tumours. These observations suggest that 99mTc-peptide-PNA probes might be useful for imaging gene expression in tumours, and the approach is worthy of further investigation.
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Affiliation(s)
- P S Rao
- Departments of Radiology, Thomas Jefferson University, Philadelphia 19107, USA
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227
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Bian Z, Wang G, Tian X, Fan J. Expression of Plasmodium falciparum-infected erythrocyte membrane protein from cerebral malaria patients. Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2003; 17:359-62. [PMID: 12563735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
AIM To provide theoretical evidence for studying the molecular pathogenesis of human cerebral malaria. METHODS The expressions of Plasmodium falciparum erythrocyte membrane protein 1(PfEMP1) on the surface of parasitized erythrocyte (PE) specimens from 19 cases of cerebral malaria patients in Yunnan Province were quantitatively analyzed by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) technique. 43 patients of falciparum malaria, 9 patients of vivax malaria and 6 healthy controls were also investigated. RESULTS The expressions of higher molecular mass (Mr) 260-320 kDa forms of PfEMP1 were found on PE from cerebral malaria patients. By contrast, the expression of PfEMP1 and P. vivax erythrocyte membrane protein (PvEMP1) on PE from falciparum malaria patients and vivax malaria patients had a PfEMP1 with Mr 240 kDa and a PvEMP1 with Mr 180 kDa band, respectively. Healthy controls expressed an EMP of Mr 140 kDa. CONCLUSION The binding of 260-320 kDa PfEMP1 proteins expressed on PE from cerebral malaria patients to diverse receptor molecules on the endothelial cell(EC) of the cerebral microvessels such as CD36, thrombospondin (TSP), intercellular adhesion molecule 1(ICAM-1), vascular cell adhesion molecule 1(VCAM-1), endothelial leukocyte adhesion molecule 1(ELAM-1) and chondroitin sulfate A (CSA) might be the molecular basis for the pathogenesis of cerebral malaria.
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Affiliation(s)
- Z Bian
- Department of Gastroenterology, Kunming General Hospital, Kunming 650032
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228
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Tian X, Zhang B. Ultrastructural observations on the formation and metabolism of calcareous corpuscles in Cysticercus cellulosae. Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2002; 16:364-7. [PMID: 12078275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
AIM To study the formation and metabolism of calcareous corpuscles from Cysticercus cellulosae at the ultrastructure level. METHODS Transmission electron microscopy. RESULTS The developmental processes of calcareous corpuscles could be divided into two stages: the intracellular formation stage and the extracellular metabolic stage. The calcareous corpuscles were formed in a cell which we named calcareous corpuscle forming cell. At the early stage of the formation, the corpuscles appeared to be secretory granules in the cells. With the development of the corpuscles, they became bead-shaped and lamellae-like, then the calcareous corpuscle forming cell enlarged and the organellae degenerated. Finally the corpuscles gathered to form particle substances with black dense background, while the nucleus and organellae of the forming cell all disappeared. There were 1-3 or 10-20 calcareous corpuscles in a mature forming cell. Then, the corpuscles were released to the parenchymal tissues and gradually appeared to be concentric lamella or an empty cavity during the metabolic process. CONCLUSION The calcareous corpuscles were formed in calcareous corpuscle forming cell and consumed in metabolic process in the parenchymal layer of Cysticercus cellulosae.
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Affiliation(s)
- X Tian
- Department of Parasitology, North China Coal Medical College, Tangshan, Hebei 063000
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229
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McLaurin J, Cecal R, Kierstead ME, Tian X, Phinney AL, Manea M, French JE, Lambermon MHL, Darabie AA, Brown ME, Janus C, Chishti MA, Horne P, Westaway D, Fraser PE, Mount HTJ, Przybylski M, St George-Hyslop P. Therapeutically effective antibodies against amyloid-beta peptide target amyloid-beta residues 4-10 and inhibit cytotoxicity and fibrillogenesis. Nat Med 2002; 8:1263-9. [PMID: 12379850 DOI: 10.1038/nm790] [Citation(s) in RCA: 328] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2002] [Accepted: 10/01/2002] [Indexed: 11/09/2022]
Abstract
Immunization of transgenic mouse models of Alzheimer disease using amyloid-beta peptide (Abeta) reduces both the Alzheimer disease-like neuropathology and the spatial memory impairments of these mice. However, a therapeutic trial of immunization with Abeta42 in humans was discontinued because a few patients developed significant meningo-encephalitic cellular inflammatory reactions. Here we show that beneficial effects in mice arise from antibodies selectively directed against residues 4-10 of Abeta42, and that these antibodies inhibit both Abeta fibrillogenesis and cytotoxicity without eliciting an inflammatory response. These findings provide the basis for improved immunization antigens as well as attempts to design small-molecule mimics as alternative therapies.
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Affiliation(s)
- J McLaurin
- Centre for Research in Neurodegenerative Diseases, University of Toronto, Toronto, Ontario, Canada.
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230
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Tian X. "Intermediate" population control and comprehensive community development. Chin J Popul Sci 2002; 5:241-50. [PMID: 12345590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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231
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Tian X. Population problems and population research in a market economy. Chin J Popul Sci 2002; 6:223-34. [PMID: 12319164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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232
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Tian X. Sustainable development of population and resources. Chin J Popul Sci 2002; 8:239-47. [PMID: 12320616] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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233
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Tian X. Population movement, marriage, and fertility change. Chin J Popul Sci 2002; 3:27-44. [PMID: 12343680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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234
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Tian X. Technological advances and the transformation of the cost of children. Chin J Popul Sci 2002; 5:1-10. [PMID: 12345186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
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235
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Mo A, Yao W, Li C, Tian X, Su M, Ling Y, Zhang Q, Setterberg RB, Jee WSS. Bipedal stance exercise and prostaglandin E2 (PGE2) and its synergistic effect in increasing bone mass and in lowering the PGE2 dose required to prevent ovariectomized-induced cancellous bone loss in aged rats. Bone 2002; 31:402-6. [PMID: 12231413 DOI: 10.1016/s8756-3282(02)00835-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Previous reports have shown that bone loss was partially prevented by bipedal stance "exercise" following ovariectomy (ovx), and it was well documented that prostaglandin E2 (PGE(2)) had an anabolic effect on the rat skeleton. The aim of this study was to determine whether lower doses of PGE(2) could prevent ovx-induced cancellous bone loss with the combination of bipedal stance exercise. Seventy-eight 10-month-old female Sprague-Dawley rats were either ovariectomized or sham-operated on day 0 and then treated with PGE(2) (0, 0.3, or 1 mg/kg per day) and/or housed in normal height cages (NC, 28 cm) or raised cages (RC, 33 cm) for 8 weeks. Bone histomorphometry was performed on the double-fluorescent-labeled proximal tibial metaphysis. In sham rats, 1 mg/kg PGE(2) + RC had synergistic effects in increasing trabecular bone area, width, and number by stimulating mineral apposition rate and bone formation rate. As expected, ovx induced cancellous bone loss, accompanied by elevated activation frequency. Without RC, PGE(2) monotherapy prevented ovx-induced bone loss at the 1 mg/kg per day dose, whereas this prevention effect was observed at the 0.3 mg/kg per day dose when combined with RC. Similar to their effects in sham rats, PGE(2) and RC had synergistic effects in augmenting cancellous bone mass and architecture and maintaining the elevated bone formation but depressing bone resorption and activation frequency. We conclude that bipedal stance exercise lowers the PGE(2) dose required to prevent ovx-induced cancellous bone loss in the proximal tibial metaphysis in aged rats.
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Affiliation(s)
- A Mo
- Radiobiology Division, University of Utah, Salt Lake City, UT 84108-1218, USA
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236
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Tian X, Yuan L, Huo X, Han X, Li Y, Xu M, Lu M, Dai J, Dong L. Ultrastructural observation on the transformation of the spermatozoon in spermatogenesis of Taeniid cestodes. Zhongguo Ji Sheng Chong Xue Yu Ji Sheng Chong Bing Za Zhi 2002; 16:269-73. [PMID: 12078256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
AIM To study the transformation of taeniid spermatozoon during spermatogenesis on the ultrastructure level. METHODS Transmission electronmicroscopy. RESULTS This paper was the second part of the ultrastructural observations on the spermatogenesis in Taeniid cestodes: The transformation of the spermatozoon. The 64-spermatid-plasmodium was generated from the secondary meiosis of the 32 rose-like secondary spermatocytes. The transformation of the spermatozoon was a complex process. Firstly, both the cytoplasm and nucleus of the spermatid elongated while the cytoplasm increased and connected to the cytoplasmic mass (cytophore). Secondly, the chromatins of nucleus polymerized to a thread-bundle-like structure. Finally, it detached from the cytoplasm mass and became a mature spermatozoon. The mature spermatozoon was a thread-like structure, about 16.2-18.6 microns in length and 0.35-0.45 micron in diameter. There were two structurally distinct parts: the part with the nucleus was the head and the part without the nucleus was the tail. The head measured about 5-6 microns in length, 1/3 of the total body length and contained an elongated nucleus which twined around the axoneme without mitochondria. The tail was about 11.2-16.6 microns in length. Throughout the core of the tail was an axoneme with typical "9 + 1" structure. The anterior of the tail, just behind the head, were some mitochondria, about 1.6-1.7 microns in total length which twined around the axoneme. The posterior of the tail contained only an axoneme. In cross-section of the spermatozoon, about 46 microtubules were beneath the plasma membrane. CONCLUSION The transformation of the spermatozoon is a very complex process.
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Affiliation(s)
- X Tian
- Department of Parasitology, North China Coal Medical College, Tangshan 063000
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Tian X, Knapp AD, Moore KJ, Brummer EC, Bailey TB. Cupule Removal and Caryopsis Scarification Improves Germination of Eastern Gamagrass Seed. Crop Sci 2002; 42:185-189. [PMID: 11756271 DOI: 10.2135/cropsci2002.1850] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Eastern gamagrass (Tripsacum dactyloides L.) is a warm-season, perennial grass with high palatability and productivity. However, poor stand establishment, often due to seed dormancy, limits its widespread use. Seed dormancy is often caused by structures surrounding the embryo, the physiological state of the embryo itself, or a combination of these factors. The eastern gamagrass dispersal unit is a floret within a thick, hard cupule. The objective of this study was to evaluate effects of cupule (including lemma and palea) removal and caryopsis scarification on germination of eastern gamagrass by means of different commercial seed lots produced in different locations and years. Germination tests were conducted at 20/30 degrees C alternating temperature with light during 30 degrees C for 8 h daily. Germination counts were made every 7 d. After 28 d, the germination of decupulated caryopses from different seed lots germinated from 16 to 49% across seed lots, compared with 5 to 18% germination for caryopses with cupule intact. Scarifying the pericarp over the embryo, however, resulted in germination of all dormant seeds. We conclude that while the cupule (including the lemma and palea) contributes to the dormancy of eastern gamagrass, the pericarp and/or testa are the main factors restricting germination of this species. In addition, caryopsis scarification increased the germination rate and the germination test could be shortened to 21 or even 14 d depending on the seed lot.
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Affiliation(s)
- X. Tian
- Dep. of Agronomy, Iowa State Univ., Ames, IA 50011. Dep. of Statistics, Iowa State Univ., Ames, IA 50011
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239
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Abstract
Sos and Ras-GRF are two families of guanine nucleotide exchange factors that activate Ras proteins in cells. Sos proteins are ubiquitously expressed and are activated in response to cell-surface tyrosine kinase stimulation. In contrast, Ras-GRF proteins are expressed primarily in central nervous system neurons and are activated by calcium/calmodulin binding and by phosphorylation. Although both Sos1 and Ras-GRF1 activate the Ras proteins Ha-Ras, N-Ras, and Ki-Ras, only Ras-GRF1 also activates the functionally distinct R-Ras GTPase. In this study, we determined which amino acid sequences in these exchange factors and their target GTPases are responsible for this signaling specificity difference. Analysis of chimeras and individual amino acid exchanges between Sos1 and Ras-GRF1 revealed that the critical amino acids reside within an 11-amino acid segment of their catalytic domains between the second and third structurally conserved regions (amino acids (aa) 828-838 in Sos1 and 1057-1067 in Ras-GRF1) of Ras guanine nucleotide exchange factors. In Sos1, this segment is in helix B, which is known to interact with the switch 2 region of Ha-Ras. Interestingly, a similar analysis of Ha-Ras and R-Ras chimeras did not identify the switch 2 region of Ha-Ras as encoding specificity. Instead, we found a more distal protein segment, helix 3 (aa 91-103 in Ha-Ras and 117-129 in R-Ras), which interacts instead primarily with helix K (aa 1002-1016) of Sos1. These findings suggest that specificity derives from the fact that R-Ras-specific amino acids in the region analogous to Ha-Ras helix 3 prevent a functional interaction with Sos1 indirectly, possibly by preventing an appropriate association of its switch 2 region with helix B of Sos1. Although previous studies have shown that helix B of Sos1 and helix 3 of Ha-Ras are involved in promoting nucleotide exchange on Ras proteins, this study highlights the importance of these regions in establishing signaling specificity.
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Affiliation(s)
- X Tian
- Department of Biochemistry, Tufts University School of Medicine, Boston, MA 02111, USA
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240
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Li WG, Zhang XY, Wu YJ, Tian X. Anti-inflammatory effect and mechanism of proanthocyanidins from grape seeds. Acta Pharmacol Sin 2001; 22:1117-20. [PMID: 11749811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
AIM To investigate the anti-inflammatory effect and mechanism of proanthocyanidins (PA) from grape seeds. METHODS Croton oil-induced ear swelling in mice and carrageenan-induced hind paw edema in rats were prepared. The nitric oxide synthase (NOS) activity was measured by NADPH-diaphoras stain assay, nitric oxide (NO) content by Griess diazotization assay, N-acetyl-beta- D-glucosaminidase (beta-NAG) activity by spectrophotography, malondialdehyde (MDA) content by thiobarbituric acid (TBA) fluorescence technique, and IL-1beta, TNFalpha, and PGE2 content by radioimmunoassay (RIA). RESULTS PA 10-40 mg/kg ip inhibited carrageenan-induced paw edema in rats and croton oil-induced ear swelling in mice in a dose-dependent manner. PA 10 mg/kg reduced MDA content in inflamed paws, inhibited beta-NAG and NOS activity, and lowered the content of NO, IL-1beta, TNFalpha, and PGE2 in exudate from edema paws of rats induced by carrageenan. The inhibitory effect of PA on all above indices was more evident than that of dexamethasone 2 mg/kg. CONCLUSION PA has anti-inflammatory effect on experimental inflammation in rats and mice. Its mechanisms of anti-inflammatory action are relevant to oxygen free radical scavenging, anti-lipid peroxidation, and inhibition of the formation of inflammatory cytokines.
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Affiliation(s)
- W G Li
- Department of Pharmacology, Lanzhou Medical College, Lanzhou 730000, China.
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241
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Wang H, Yang L, Tian X, Chen YZ. Sesquiterpene polyol esters from Euonymus phellomana Loes. Pharmazie 2001; 56:889-91. [PMID: 11817177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Three new (1-3) and six known (4-9) beta-dihydroagarofuran sesquiterpene polyol esters were isolated from a methanol extract of the seed oil of Euonymus phellomana Loes. and their structures were established on the basis of spectral analysis, including 2D-NMR spectroscopy.
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Affiliation(s)
- H Wang
- National Laboratory of Applied Organic Chemistry, Lanzhou University, Gansu Province, P.R. China
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242
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Abstract
Ras-GRF1 and Ras-GRF2 constitute a family of calmodulin-regulated guanine-nucleotide exchange factors (GEFs) that activate Ras proteins. Here we show that whereas Ras-GRF1 activated both Ha-Ras and R-Ras in cells, Ras-GRF2 activated only Ha-Ras. The inability of Ras-GRF2 to activate R-Ras was the consequence of the GTPase being post-translationally modified, since Ras-GRF2 activated unprocessed R-Ras as effectively as unprocessed Ha-Ras when assays were performed either in vivo or in vitro. Moreover, Ras-GRF2 failed to activate fully processed R-Ras in vitro. The particular C-terminal lipid attached to the GTPases played an important role in determining signaling specificity, since R-Ras became more responsive to Ras-GRF2 when it was farnesylated instead of geranylgeranylated. Similarly, Ha-Ras became less responsive to Ras-GRF2 when it was geranylgeranylated instead of farnesylated. Analysis of chimeras between Ras-GRF1 and Ras-GRF2 demonstrated that a 30-amino acid segment embedded with their catalytic domains was responsible for recognizing the presence of different lipids on Ras proteins. These results indicate that the specific lipid moiety attached to GTPases can contribute to signaling specificity of Ras-GEFs.
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Affiliation(s)
- T Gotoh
- Department of Biochemistry, Tufts University School of Medicine, Boston, Massachusetts 02111, USA
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243
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Tian X, Iwatsu M, Sado K, Kanai A. Studies on the uptake and release of fluoroquinolones by disposable contact lenses. CLAO J 2001; 27:216-20. [PMID: 11725985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
PURPOSE To evaluate the ability of three types of disposable contact lenses to take up and release three kinds of fluoroquinolones in vitro. METHODS We evaluated three FDA-approved disposable soft contact lenses (1-Day Acuvue, Medalist, and 14UV) for their ability to absorb and release three kinds of fluoroquinolones. Contact lenses were presoaked in fluoroquinolones for 1, 4, and 24 hours, and the uptake was determined by measuring the concentration of fluoroquinolones in the three types of disposable soft contact lenses by high pressure liquid chromatography (HPLC). After uptake, the lenses were placed in fresh saline baths, and release rates from the lenses were determined by measuring the concentration of fluoroquinolones in the saline baths by HPLC. RESULTS The disposable soft contact lens with the highest uptake of fluoroquinolones was the 1-Day Acuvue. After presoaking, drug concentrations in the 1-Day Acuvue and Medalist were higher than their theoretical saturation concentrations (i.e., the concentration of the fluoroquinolone eye drops [0.3%]). The release rates from the 1-Day Acuvue and Medalist lenses were slower than for the 14 UV lens. CONCLUSIONS These results indicate that among the lenses tested, the most practical drug delivery system is the 1-Day Acuvue disposable soft contact lens.
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Affiliation(s)
- X Tian
- Department of Ophthalmology, Juntendo University School of Medicine, Tokyo, Japan
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244
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Lorenzen JH, Balbyshev NF, Lafta AM, Casper H, Tian X, Sagredo B. Resistant potato selections contain leptine and inhibit development of the Colorado potato beetle (Coleoptera: Chrysomelidae). J Econ Entomol 2001; 94:1260-1267. [PMID: 11681692 DOI: 10.1603/0022-0493-94.5.1260] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
We recently described a new source of host-plant resistance to the Colorado potato beetle, Leptinotarsa decemlineata (Say), in a tetraploid potato (Solanum tuberosum L.) selection, ND2858-1. This genotype, and selected backcross progeny, had little damage while check cultivars were defoliated in open-choice field assays. To further characterize the observed deterrence, we determined foliar glycoalkaloids and conducted no-choice assays with ND2858-1 backcross progeny genotypes (ND4382-n). Development of neonate L. decemlineata in detached leaf assays on resistant progeny genotypes was delayed and larval weight gain after 4 d was inhibited by 75% relative to larval development and weight gain on susceptible genotypes. Inhibition of larval development in detached leaf assays with the selected progeny genotypes was equivalent to that of high-leptine genotypes of S. chacoense Bitter. Foliar glycoalkaloids of resistant genotypes included low levels of leptines I and II. The unlikely nature of this cross and the presence of leptine in this and resistant progeny selections cast doubt on the recorded pedigree. Molecular analyses were conducted by restriction fragment-length polymorphism and amplified fragment-length polymorphisms. Both methods established a high degree of relatedness to S. tuberososum and S. chacoense but not to S. fendleri. We conclude that ND2858-1 did not originate from a cross with S. fendleri, but is likely derived from S. chacoense. Oviposition and larval survival were reduced when adult L. decemlineata were placed in cages with resistant genotypes; an effect that was enhanced by inclusion of Perillus bioculatus F. Therefore, the nonpreference previously observed in open-choice field defoliation assays is also associated with antibiotic effects on L. decemlineata. The resistance may be caused by leptines, but is greater than would be expected by the leptine content. This source of host plant resistance could be a cost-effective management strategy, especially if combined with other resistance mechanisms or compatible control measures to delay development of resistance in the target insects.
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Affiliation(s)
- J H Lorenzen
- Department of Plant Sciences, North Dakota State University, Fargo 58105, USA. Jim
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245
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Xiao C, Lu J, Tian X, Li X, Zhou P. [Fermentation conditions for production of alkaline elastase by alkaliphilic Bacillus XE22-4-1]. Wei Sheng Wu Xue Bao 2001; 41:611-6. [PMID: 12552811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
A extracellular alkaline elastase producing bacterial strain Bacillus XE22-4-1, with the optimum pH of 10.0 for its growth, was isolated and screened from alkali lake of Tibet. 2% glucose and 0.25% yeast extract are respectively the appropriate carbon and nitrogen source on elastase production. Soymeal can promote elastase production. The fermentation conditions in a 2 L stirred tank were investigated. The results have revealed that the dissolved oxygen is the most effective factor on elastase production. The maximum elastolytic activity reached 266 u/mL among 48 hours of fermentation by combination of enhancing aeration and changing the mixing speed.
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Affiliation(s)
- C Xiao
- Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080, China
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246
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Tian X, Iwatsu M, Kanai A. Disposable 1-day Acuvue contact lenses for the delivery of lomefloxacin to rabbits' eyes. CLAO J 2001; 27:212-5. [PMID: 11725984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
PURPOSE To investigate the ability of a disposable soft contact lens (1-Day Acuvue) to deliver lomefloxacin, a fluoroquinolones antibiotic, into the cornea and aqueous humor of rabbits. METHODS Experiments were conducted on adult albino rabbits. 1-Day Acuvue lenses were immersed for 1 hour in commercially-available lomefloxacin eye solution and then placed on the cornea. After 0.5, 2, 4,6, and 8 hours, the animals were killed and the lenses were removed and placed into a 20 mL saline bath. Corneal tissue and aqueous humor samples were also obtained at these times. The release of lomefloxacin from the lenses was calculated by measuring the amount of drug remaining in the lenses after removal from the rabbit eyes. The concentration of lomefloxacin in the cornea and anterior chamber following the wearing of lomefloxacin-loaded lenses was compared with the concentrations following frequent-drop therapy (one drop of lomefloxacin hourly for 8 hours). RESULTS In vivo, lomefloxacin was released from 1-Day Acuvue lenses gradually over 8 hours. The cornea and aqueous humor levels in the eyes following the wear of lomefloxacin-loaded lenses were significantly higher than those achieved by frequent-drop therapy. The drug levels in the cornea and aqueous humor generally remained above the 90% minimal inhibitory concentration for 8 hours in the 1-Day Acuvue lens group. CONCLUSIONS 1-Day Acuvue contact lenses soaked in 0.3% lomefloxacin can release sufficient amounts of lomefloxacin and in this study produced higher levels in both the cornea and aqueous humor than that achieved by frequent-drop therapy for up to 8 hours. We conclude that 1-Day Acuvue contact lens can be used as a drug delivery system for lomefloxacin.
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Affiliation(s)
- X Tian
- Department of Ophthalmology, Juntendo University School of Medicine, Tokyo, Japan
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247
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Abstract
Two enmein type diterpenoids, taibaijaponicains A and B, were isolated from the ethanol extract of the leaves and branches of Isodon japonica. Their structures are designated as 6beta,11alpha-dihydroxy-16alpha-methoxymethyl-6,20-epoxy-6,7-seco-ent-kaur-15-one-1,7-olide and 3beta-acetoxy-6beta,11alpha-dihydroxy-16alpha-methoxymethyl-6,20-epoxy-6,7-seco-ent-kaur-15-one-1,7-olide, respectively, on the basis of detailed spectroscopic analyses.
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Affiliation(s)
- B Li
- Department of Chemistry, Shaanxi Normal University, 710062, Xi'an, People's Republic of China.
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248
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Abstract
A critical feature in the pathogenesis of the respiratory pathogen Histoplasma capsulatum is the conversion from the mold form (found in soil) to the yeast form in the lungs of the host. Little is known about the molecular biology of Histoplasma dimorphism. In particular, the possible roles of genes which are transcriptionally silent in yeast (i.e. mold-specific) have not been studied. We have produced a cDNA library highly enriched for mold-upregulated clones by fragmenting cDNA and removing yeast-specific and common sequences with a highly efficient enzyme degrading subtraction method. Screening of randomly selected clones identified cDNA fragments representing 16 different mold-upregulated genes. Because multiple cDNA fragments can be treated as alleles in a genetic screen, we were able to apply probability analysis to estimate the total number of mold-upregulated genes. We estimate that there are 27 upregulated genes; cDNA fragments of 16 have been isolated. Here we report the first isolation and analysis of cDNA from two mold-specific genes, MS8 (GenBank AF292398) and MS88 (GenBank AF357882). The MS8 transcript was very strongly expressed in mold but not detected on Northern blots with yeast RNA. The putative MS8 protein was predicted to be 21.3 kDa (203 aa), very rich in glutamine and glycine and had a calculated pI of 6.76. The MS88 transcript was weakly expressed in mold and not detected in yeast. The putative MS88 protein was predicted to be 22.5 kDa (219 aa) with a pI of 4.46. GenBank similarity searches revealed that the putative MS8 protein was similar to a glutamine-rich protein, of unknown function, from the fungus Colletotrichum gloeosporioides (GenBank U94186). No significant matches were found for the putative MS88 protein.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Blotting, Northern
- Cloning, Molecular
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- DNA, Fungal/genetics
- Fungal Proteins/genetics
- Gene Dosage
- Gene Expression Regulation, Fungal
- Histoplasma/genetics
- Histoplasma/growth & development
- Molecular Sequence Data
- RNA, Fungal/genetics
- RNA, Fungal/metabolism
- Sequence Analysis, DNA
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Affiliation(s)
- X Tian
- Biological Sciences Department, Center for Molecular and Cellular Biosciences, University of Southern Mississippi, Hattiesburg, MS 39406-5018, USA
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249
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Qu P, Ding Y, Xia D, Wang H, Tian X. Variations in cardiac diastolic function in hypertensive patients with different left ventricular geometric patterns. Hypertens Res 2001; 24:601-4. [PMID: 11675957 DOI: 10.1291/hypres.24.601] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
To evaluate the alteration of cardiac function in hypertensive patients with different left ventricular geometric patterns. Echocardiography was used to study left ventricular geometry and cardiac diastolic function in 117 cases of essential hypertension, with 45 normal cases as controls. Echocardiographic date were used to calculated the left ventricular mass index (LVMI) and relative wall thickness (RWT), which values in turn were used to divide the subjects into four groups. The left atrial dimension of the group, with the exception of these hypertensives who showed normal geometry, was larger than that of the control group. The damage of peak of E velocity, peak of A velocity, E/A and the slope between the E and F points (E to F slope) were greater than in hypertension than in the control group. The concentric hypertrophy group and eccentric hypertrophy group suffered more serious damage of left ventricular diastolic function than the concentric remodeling group, and damage of left ventricular diastolic function in the concentric remodeling group was greater than that in the normal geometry group. The degree of cardiac diastolic function damage differed among patients with different left ventricular geometric patterns, when the cardiac structure was changed, the degree of cardiac diastolic function damage increased.
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Affiliation(s)
- P Qu
- Cardiovascular Department of Internal Medicine, the Second Affiliated Hospital of Dalian Medical University, China.
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250
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Qiao Q, Wang X, Wang M, Tian X. [Magnetic stimulation: theory and advance]. Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2001; 18:484-7. [PMID: 11605522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Magnetic stimulation is a noninvasive diagnostic and therapeutic technique. The basic theory of magnetic stimulation is presented briefly. Its advances are elaborated in three aspects of mechanism, instrumentation and applications. The problems in focality, location, safety and its trend are discussed.
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Affiliation(s)
- Q Qiao
- School of Precision Instrument & Optoelectronics, Tianjin University, Tianjin 300072
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