bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison between PMSG‐ and FSH‐induced superovulation for the generation of transgenic rats
Authors: Popova Elena , Krivokharchenko Alexander , Ganten Detlev , Bader Michael 
Published: September 2002

AbstractSuperovulation protocols using single injections of pregnant mare's serum gonadotropin (PMSG) or minipumps with follicle‐stimulating hormone (FSH) were compared in immature Sprague–Dawley (SD) rats. We used the following criteria: total number of ova, rate of fertilization, in vitro embryo development, sensitivity of zygotes to the microinjection of foreign DNA into the pronucleus, and their in‐vivo development after transplantation into the oviduct of a recipient. Female SD rats were stimulated with 15 IU PMSG or 10 mg FSH followed by the injection of human chorionic gonadotropin (hCG) at doses of 20 and 30 IU per female. After hCG administration, they were mated with males of the same strain and sacrificed on day 1 of pregnancy. The percentage of mated animals and the fertilization rate was similar in all groups. In rats given PMSG, the number of ovulated zygotes was hCG dose‐dependent. In contrast, the dose of hCG did not influence the efficiency of superovulation in rats given FSH, which was equal to PMSG‐treated rats at the optimal dose of hCG. The rates of in vitro blastocyst development (31.4 and 23.3%) and the resistance to microinjection into the pronucleus did also not differ significantly between zygotes of both studied groups. The proportion of offspring developing from microinjected zygotes after oviduct transfer (26.2 and 26.8%, respectively) and the rate of transgene integration per newborns (7.3 and 4.9%, respectively) was similar in both experimental groups. The results of this study demonstrate that superovulation of immature SD rats by PMSG is equally effective as FSH treatment and, thus, preferable for transgenic rat technology due to the lower costs and easier handling Mol. Reprod. Dev. 63: 177–182, 2002. © 2002 Wiley‐Liss, Inc.
Cross‐linking of ZP2 and ZP3 by transglutaminase is required for the formation of the outer layer of fertilization envelope of carp egg
Authors: Chang Yea‐Sha , Wang Yu‐Wen , Huang Fore‐Lien 
Published: September 2002

AbstractA transglutaminase (TGase) cDNA was cloned from carp ovary. It was highly homologous to zebrafish TGase. Immunoblot and enzymatical assay showed that TGase was present on the chorion and in the cytoplasm of carp eggs. Addition of TGase inhibitor, cadaverine or ethylene diaminetetracetic acid (EDTA) to the cortical reaction medium impaired the formation of the outer layer of fertilization envelope (FEo), the adhesive structure of carp egg. Fibroin‐like substance (FLS), cystatin, cathepsin‐like substance (CLS), and FEO‐1 were the components of FEo, wherein the majority of the former three were conjugated to form macromolecules of 90–205 kDa while the latter one was present in monomer of 22 kDa. Cadaverine interfered slightly the discharge of FLS conjugates out of the perivitelline space (PVS) but affected profoundly the recruitment of FLS conjugates to FE, whereas EDTA completely inhibited both the release and the recruitment of FLS conjugates to FE. Both EDTA and cadaverine did not inhibit the discharge of FEO‐1 out of PVS but could inhibit the recruitment of FEO‐1 to FE. The mechanism was studied. ZP2 and ZP3, the major constituents of inner layer of FE, were cross‐linked during cortical reaction, which rendered FE hardened. In the presence of EDTA, the cross‐linking of ZP2 and ZP3 were inhibited, thus FE remained soft. The PVS of an egg with a hardened FE was less expanded than an egg with a soft FE. It was assumed that a less expanded PVS would generate a higher fluid pressure than a more expanded PVS did. Therefore, the transportation of the macromolecules such as the FLS‐cystatin‐CLS conjugates out of PVS was facilitated in control and cadaverine‐treated eggs whose FE were hardened but was blocked in EDTA‐treated eggs whose FE were unhardened. On the other hand, the transportation of small molecules such as FEO‐1 out of FE was not restrained, so they were discharged out of the PVS of the control and TGase inhibitor‐treated eggs. In addition, TGase activity was also required for the recruitment of FLS conjugates to FE. Mol. Reprod. Dev. 63: 237–244, © 2002 Wiley‐Liss, Inc.
Link protein as an enhancer of cumulus cell–oocyte complex expansion
Authors: Sun Guang Wei , Kobayashi Hiroshi , Suzuki Mika , Kanayama Naohiro , Terao Toshihiko 
Published: September 2002

AbstractTo investigate the specific components involved in regulating cumulus cell–oocyte complex (COC) expansion in an in vitro mouse experiment, freshly‐isolated COC were cultured in the presence of various combinations of FSH (1.0 μg/ml), proteins of the inter‐α‐inhibitor (IαI) family (a light chain, also known as bikunin, heavy chains [HC1 +  HC2] and IαI [0.01–2.0 μg/ml]) and link protein (LP) (0.016–10 μg/ml) for 24 h and were observed for expansion of their cumulus cells (percent of COC with + 3 and + 4 expansion and average projected area). The COC were videotaped in real time at the initiation of culture and after 24 h of culture. FSH alone did not stimulate cumulus expansion under serum‐free conditions; however, treatment with IαI (0.1–2.0 μg/ml) or heavy chains (10 μg/ml), but not bikunin (10 μg/ml), in the presence of FSH significantly increased COC expansion, with maximal promotion occurring at 1.0 μg/ ml of IαI. Addition of LP (2.0 μg/ml) to the medium containing IαI (1.0 μg/ml) and FSH resulted in significantly higher expansion levels than were observed in response to IαI alone, although LP alone (10 μg/ml) had no or very little effect by itself. Anti‐IαI or anti‐LP polyclonal antibody, which inhibits binding of IαI and LP, respectively, to hyaluronic acid (HA), markedly reduced expansion of the surrounding cumulus cell extracellular matrices. Therefore, in vitro, LP might serve, in part, to enhance the COC expansion possibly by stabilizing HA‐IαI (or heavy chains) complex on the surrounding cumulus cell matrices. Mol. Reprod. Dev. 63: 223–231, © 2002 Wiley‐Liss, Inc.
Capacitation state‐dependent changes in adenosine receptors and their regulation of adenylyl cyclase/cAMP
Authors: Adeoya‐Osiguwa Susan A. , Fraser Lynn R. 
Published: September 2002

AbstractThis study was designed to localize adenosine receptors and to provide evidence that specific receptors are active only in either uncapacitated or capacitated mouse spermatozoa, where they play a role in regulating cAMP production. Using specific antibodies, stimulatory A2A receptors were localized primarily on the acrosomal cap region and the flagellar principal piece. Interestingly, the staining was much more pronounced in uncapacitated than in capacitated spermatozoa, suggesting capacitation‐dependent changes in epitope accessibility. A1 receptors showed a very similar distribution, but the staining was markedly greater in capacitated than in uncapacitated cells. After addition of purified decapacitation factor (DF) to capacitated cells, strong staining for A2A was regained, suggesting reversibility in epitope accessibility. Chlortetracycline analysis revealed that an agonist specific for A2A receptors had no detectable effect on capacitated cells, but after DF‐induced decapacitation, the agonist then stimulated capacitation. That agonist also significantly stimulated cAMP production in uncapacitated cells, had no effect on capacitated cells, but regained the ability to stimulate cAMP in the latter following DF treatment. In contrast, an A1 agonist inhibited cAMP in capacitated cells. These results indicate that specific adenosine receptors function in a reversible manner in one or other capacitation state, resulting in regulation of cAMP. Mol. Reprod. Dev. 63: 245–255, © 2002 Wiley‐Liss, Inc.
Molecular cloning and sequencing of cDNA encoding for human FA‐1 antigen
Authors: Naz Rajesh K. , Zhu Xiaolong 
Published: September 2002

AbstractThe cDNA encoding for the human FA‐1 sperm antigen was cloned and sequenced from the in‐house constructed subtractive human testis cDNA expression library in λZiplox using the FA‐1 monoclonal antibody (mAb). The full‐length sequence was obtained by using the 5′ rapid amplification of 5′‐cDNA end (5′‐RACE) procedure. It is 1,576‐bp long, and has an open reading frame (ORF) of 283 amino acids (aa) with the first ATG Met start codon at nucleotide (nt) 57 and the stop codon TAG at nt 906. It has two termination codons at the 5′ end before the ATG start codon. The translated protein has a calculated molecular weight of 32.1 kDa and estimated isoelectric point (pI) of 11.59. It has one potential N‐linked glycosylation site and one tyrosine phosphorylation site, besides several O‐linked glycosylation and serine and threonine phosphorylation sites. Hydrophilicity analysis of the deduced aa sequence showed it to be a membrane‐anchored protein. Extensive computer search in the database did not identify any known nt/aa sequence having homology with FA‐1 cDNA or deduced aa, indicating it to be a novel gene. The Northern blot and reverse transcription‐polymerase chain reaction (RT‐PCR)–Southern blot analyses indicated the testis‐specific expression of FA‐1 antigen at the mRNA level. The ORF of the FA‐1 was subcloned into pGEX‐1λT for expression. The expressed FA‐1 recombinant protein had a molecular size of ∼40 kDa, and was recognized by the FA‐1 mAb, and not by the myeloma control Ig. The rabbit antibodies (Ab) raised against the recombinant (r) FA‐1 antigen recognized the rFA‐1 antigen as well as the native (n) FA‐1 antigen. The rFA‐1 Ab specifically recognized a protein band of ∼50 kDa in human testis extract in the Western blot involving 11 types of human tissue extracts, indicating the testis‐specific expression of FA‐1 at the protein level. The Ab showed binding with live and methanol‐fixed human sperm at the post‐acrosomal, mid‐piece, and tail regions. The Ab caused a significant (P < 0.001) and concentration‐dependent inhibition of human sperm capacitation/acrosome reaction by blocking tyrosine phosphorylation of the FA‐1 antigen. The sperm‐specific human FA‐1 recombinant antigen may find applications in immunocontraception, and diagnosis and treatment of immunoinfertility in humans. Mol. Reprod. Dev. 63: 256–268, © 2002 Wiley‐Liss, Inc.
Proton electron double resonance imaging of the in vivo distribution and clearance of a triaryl methyl radical in mice
Authors: Li Haihong , Deng Yuanmu , He Guanglong , Kuppusamy Periannan , Lurie David J. , Zweier Jay L. 
Published: September 2002

AbstractProton electron double resonance imaging (PEDRI) measures the spatial distribution of paramagnetic species in biological samples using the Overhauser effect. Triaryl methyl (TAM) free radicals have been developed as a spin probe for PEDRI since they have very long T1e. Therefore, low RF power levels are sufficient to saturate the electron spin system with resultant high NMR enhancement facilitating application of PEDRI in living animals. In this report, PEDRI studies were performed at 0.02 T. The power‐dependent image enhancement was studied using phantoms of TAM in saline, then the distribution and pharmacokinetics of TAM in living mice were measured. Following intravenous administration of 0.7 mmol/kg of TAM, enhancements of up to −34 were observed enabling visualization of its distribution within the body. Maximum uptake of TAM in the vascular compartment was seen 1 min postadministration with half‐clearance within 5 min. Maximum uptake in the kidneys occurred at 10 min with half‐clearance at 26 min and maximum accumulation in the bladder after 50 min. Thus, TAM is initially compartmentalized in the vasculature and this is followed by rapid uptake and excretion by the kidneys. PEDRI enabled rapid imaging of the distribution and clearance of this paramagnetic probe and this information should facilitate the use of TAM as a label for oximetry and other applications. Magn Reson Med 48:530–534, 2002. © 2002 Wiley‐Liss, Inc.
Frequency‐modulated steady‐state free precession imaging
Authors: Foxall D.L. 
Published: September 2002

AbstractExploration of the possibilities of steady‐state free precession (SSFP) excitation has led to the discovery that it is tolerant of slow variations in spectral offset frequency. The effect has been used to eliminate banding artifacts from images obtained with the fully balanced SSFP imaging sequence. Magn Reson Med 48:502–508, 2002. © 2002 Wiley‐Liss, Inc.
Continuous arterial spin labeling using a local magnetic field gradient coil
Authors: Trampel Robert , Mildner Toralf , Goerke Ute , Schaefer Andreas , Driesel Wolfgang , Norris David G. 
Published: September 2002

AbstractContinuous arterial spin labeling (ASL) using a locally induced magnetic field gradient for adiabatic inversion of spins in the common carotid artery of human volunteers is demonstrated. The experimental setup consisted of a helmet resonator for imaging, a circular RF surface coil for labeling, and gradient loops to produce a magnetic field gradient. A spin‐echo (SE) echo‐planar imaging (EPI) sequence was used for imaging. The approach is independent of the gradients of the MR scanner. This technology may be used if the imaging gradient system does not produce an appropriate magnetic field gradient at the location of the carotid artery—for example, in a head‐only scanner—and is a prerequisite for the development of a system that allows continuous labeling during the imaging experiment. Magn Reson Med 48:543–546, 2002. © 2002 Wiley‐Liss, Inc.
MRI of lungs using partial liquid ventilation with water‐in‐perfluorocarbon emulsions
Authors: Huang Ming Qiang , Ye Qing , Williams Donald S. , Ho Chien 
Published: September 2002

AbstractA novel 1H‐MRI contrast modality for rat lungs has been developed using water‐in‐perfluorocarbon (PFC) emulsions for partial liquid ventilation™ (PLV). The feasibility of the new ventilation protocol for 1H‐MRI studies of lungs has been demonstrated. 1H‐MR images of lungs have been obtained with sensitivity and spatial resolution higher than those of the 19F‐MRI of lungs previously reported. Diffusion‐weighted MRI measurements of lungs showed that the results obtained are related to the pulmonary architecture and functional properties of lungs. Although the methodology needs further improvement and evaluation, it appears to have great potential in a wide range of new applications in the field of lung MRI, such as in vivo detection of lung cancer, emphysema, and allograft rejection following lung transplantation. The ability of this technique to achieve high‐quality MR images of lungs, together with its technical simplicity, stability, and low cost, makes this method a promising imaging technique for the lungs. Magn Reson Med 48:487–492, 2002. © 2002 Wiley‐Liss, Inc.
Quantitation of absolute 2H enrichment of plasma glucose by 2H NMR analysis of its monoacetone derivative
Authors: Jones John G. , Perdigoto Rui , Rodrigues Tiago B. , Geraldes Carlos F.G.C. 
Published: September 2002

AbstractA simple 2H NMR method for quantifying absolute 2H‐enrichments in all seven aliphatic positions of glucose following its derivatization to monoacetone glucose is presented. The method is based on the addition of a small quantity of 2H‐enriched formate to the NMR sample. When the method was applied to [2‐2H]monoacetone glucose samples prepared from [2‐2H]glucose standards of known enrichments in the range of 0.2–2.5%, enrichment estimates derived by the NMR method were in good agreement with the real enrichment values of the [2‐2H]glucose precursors. The measurement was also applied to monoacetone glucose derived from human plasma glucose samples following administration of 2H2O and attainment of isotopic steady state, where glucose H2 and body water enrichment are equivalent. In these studies, the absolute H2 enrichment of plasma glucose estimated by the formate method was in good agreement with the 2H‐enrichment of body water measured by an independent method. Magn Reson Med 48:535–539, 2002. © 2002 Wiley‐Liss, Inc.
Recessed elliptical‐centric view‐ordering for contrast‐enhanced 3D MR angiography of the carotid arteries
Authors: Watts R. , Wang Y. , Redd B. , Winchester P.A. , Kent K.C. , Bush H.L. , Prince M.R. 
Published: September 2002

AbstractFast arterial‐venous transit in the carotid arteries requires accurate, reliable timing of the acquisition to the bolus transit to maximize arterial signal and minimize venous artifacts. The rising edge of the bolus is not utilized in conventional elliptical‐centric view‐ordering because the critical k‐space center must be acquired with full arterial enhancement. In this study, a recessed elliptical‐centric view‐ordering scheme is introduced in which the k‐space center is acquired a few seconds following scan initiation. The recessed view‐ordering is shown to be more robust to timing errors than the conventional scheme in a study of 37 patients. Magn Reson Med 48:419–424, 2002. © 2002 Wiley‐Liss, Inc.
Preliminary report on in vivo coronary MRA at 3 Tesla in humans
Authors: Stuber Matthias , Botnar René M. , Fischer Stefan E. , Lamerichs Rolf , Smink Jouke , Harvey Paul , Manning Warren J. 
Published: September 2002

AbstractCurrent limitations of coronary magnetic resonance angiography (MRA) include a suboptimal signal‐to‐noise ratio (SNR), which limits spatial resolution and the ability to visualize distal and branch vessel coronary segments. Improved SNR is expected at higher field strengths, which may provide improved spatial resolution. However, a number of potential adverse effects on image quality have been reported at higher field strengths. The limited availability of high‐field systems equipped with cardiac‐specific hardware and software has previously precluded successful in vivo human high‐field coronary MRA data acquisition. In the present study we investigated the feasibility of human coronary MRA at 3.0T in vivo. The first results obtained in nine healthy adult subjects are presented. Magn Reson Med 48:425–429, 2002. © 2002 Wiley‐Liss, Inc.
Volume of rat lungs measured throughout the respiratory cycle using 19F NMR of the inert gas SF6
Authors: Kuethe Dean O. , Behr Volker C. , Begay Stephanie 
Published: September 2002

AbstractThe lung volumes of mechanically ventilated rats were measured over the course of the respiratory cycle using the NMR signal strength from inhaled sulfurhexafluoride. Rats with elastase‐induced emphysema showed larger lung volumes and slower exhalation than control rats. For humans the technique should be able to provide lung volume measurements at least 20 times a second. Magn Reson Med 48:547–549, 2002. © 2002 Wiley‐Liss, Inc.
Quantitative 1H‐magnetic resonance spectroscopy of human brain: Influence of composition and parameterization of the basis set in linear combination model‐fitting
Authors: Hofmann L. , Slotboom J. , Jung B. , Maloca P. , Boesch C. , Kreis R. 
Published: September 2002

AbstractLocalized short‐echo‐time 1H‐MR spectra of human brain contain contributions of many low‐molecular‐weight metabolites and baseline contributions of macromolecules. Two approaches to model such spectra are compared and the data acquisition sequence, optimized for reproducibility, is presented. Modeling relies on prior knowledge constraints and linear combination of metabolite spectra. Investigated was what can be gained by basis parameterization, i.e., description of basis spectra as sums of parametric lineshapes. Effects of basis composition and addition of experimentally measured macromolecular baselines were investigated also. Both fitting methods yielded quantitatively similar values, model deviations, error estimates, and reproducibility in the evaluation of 64 spectra of human gray and white matter from 40 subjects. Major advantages of parameterized basis functions are the possibilities to evaluate fitting parameters separately, to treat subgroup spectra as independent moieties, and to incorporate deviations from straightforward metabolite models. It was found that most of the 22 basis metabolites used may provide meaningful data when comparing patient cohorts. In individual spectra, sums of closely related metabolites are often more meaningful. Inclusion of a macromolecular basis component leads to relatively small, but significantly different tissue content for most metabolites. It provides a means to quantitate baseline contributions that may contain crucial clinical information. Magn Reson Med 48:440–453, 2002. © 2002 Wiley‐Liss, Inc.
UNFOLD using a temporal subtraction and spectral energy comparison technique
Authors: Wu Yijing , Jeong Eun‐Kee , Parker Dennis L. , Alexander Andrew L. 
Published: September 2002

AbstractIn dynamic MRI, several methods have been demonstrated to increase acquisition speed by decreasing the number of sequential phase encodings. The UNFOLD technique interleaves the measurements of k‐space, reconstructs aliased images from each k‐space interleaf, and applies a temporal low‐pass filter to obtain the nonaliased images. However, low‐pass filter resolution of the nonaliased images fails if there is overlap between the spatially aliased temporal spectra. In this study a subtraction method was used to remove the static portion of the image. The aliased and nonaliased dynamic portions are then resolved by comparing the temporal energy of bands in the power spectrum. This method was combined with the 3D 2×2 UNFOLD (a factor of 2 interleaves in two directions) technique. The combination resulted in a factor of 4 improvement in acquisition speed. Application of this method to a time‐resolved, contrast‐enhanced flow phantom study is presented. Magn Reson Med 48:559–564, 2002. © 2002 Wiley‐Liss, Inc.
Mapping at glomerular resolution: fMRI of rat olfactory bulb
Authors: Kida Ikuhiro , Xu Fuqiang , Shulman Robert G. , Hyder Fahmeed 
Published: September 2002

AbstractThe rat olfactory bulb contains ∼2000 functional units called glomeruli which are used to recognize specific characteristics of odorants. Activity localization of individual glomerulae (∼0.002 μL) has important consequences for understanding mechanisms in olfactory information encoding. High‐resolution functional MRI (fMRI) data from the rat olfactory bulb are presented using the blood oxygenation level dependent (BOLD) method at 7 T. Either individual or clusters of fMRI voxels suggestive of activity in the olfactory nerve and glomerular layers were reproducibly detected with repeated 2‐min exposures of iso‐amyl acetate at spatial resolution of 0.001–0.003 μL. The importance of glomerular clustering for olfaction and the implications of BOLD mapping with even higher spatial resolution (i.e., ≪0.001 μL voxels) are discussed. High‐resolution in vivo mapping of the rat olfactory bulb with fMRI at high magnetic field promises to provide novel data for understanding olfaction. Magn Reson Med 48:570–576, 2002. © 2002 Wiley‐Liss, Inc.
Correction of concomitant magnetic field‐induced image artifacts in nonaxial echo‐planar imaging
Authors: Du Yiping P. , Joe Zhou Xiaohong , Bernstein Matt A. 
Published: September 2002

AbstractEcho‐planar images acquired in nonaxial planes are often distorted. Such image distortion has limited the applications of the echo‐planar imaging (EPI) technique. In this article, it is demonstrated that a considerable amount of the distortion is caused by the higher‐order magnetic field concomitant with the linear magnetic field gradient, or the concomitant magnetic field. The image distortion caused by the concomitant magnetic field is more prominent when a higher gradient amplitude is used for readout. It is also shown that the concomitant magnetic field can cause ghosting and blurring. A theoretical analysis is performed for the concomitant field effect in nonaxial EPI images. A point‐by‐point (or line‐by‐line) phase correction algorithm is developed to correct the image distortion, ghosting, and blurring. A postreconstruction processing algorithm is also developed to correct image distortion with much higher computational efficiency. Experimental results show that both correction methods effectively reduce the image distortion in coronal or sagittal images. Magn Reson Med 48:509–515, 2002. © 2002 Wiley‐Liss, Inc.