bluuebunny/crossref_metadata_2025_split huggingface dataset:
Early epoetin alfa treatment in children with solid tumors
Authors: Zoubek Andreas , Kronberger Martina 
Published: September 2002

AbstractBackgroundCombination chemotherapy is often used for long periods in children with solid malignancies, leading to anemia and necessitating intervention with red blood cell (RBC) transfusions. Transfusions, however, are associated with a variety of adverse events and risks. Recombinant human erythropoietin (rHuEPO, epoetin alfa) has been shown to reduce the need for transfusions and to ameliorate the symptoms of anemia in adults, but few studies have been conducted thus far in pediatric patients.ProcedureThirty‐seven children with solid tumors receiving treatment with platinum‐ or nonplatinum‐based chemotherapy were treated with epoetin alfa and supplemental iron in a single‐center, open‐label, 28‐week, case‐control study.ResultsEpoetin alfa significantly reduced the need for RBC (P = 0.007) and platelet (P = 0.01) transfusions, and prolonged the time to first RBC transfusion (P = 0.0004) as compared to the control group. Moreover, epoetin alfa was effective in maintaining mean hemoglobin levels during the course of the study, whereas they declined below baseline after week 9 in the control group.ConclusionsEpoetin alfa is effective and safe in reducing transfusion requirements and maintaining adequate hemoglobin levels in children with solid tumors undergoing combination chemotherapy. Med Pediatr Oncol 2002; 39:459–462. © 2002 Wiley‐Liss, Inc.
Recombinant human erythropoietin in pediatric oncology: A review
Authors: Feusner James , Hastings Caroline 
Published: September 2002

AbstractBackgroundNumerous reports on recombinant human erythropoietin (rHuEPO, epoetin alfa) treatment of cancer‐related anemia in adult patients have been published to date. These have shown that epoetin increases hemoglobin levels, significantly ameliorates symptoms of anemia, and improves adult patients' quality of life. Unfortunately, less is known about the impact of epoetin on anemia in pediatric cancer patients.ProcedureIt is the objective of this review to summarize and analyze data of clinical trials of epoetin treatment of anemia in pediatric cancer patients.ResultsA total of 15 studies were reviewed; eight were considered for detailed analysis and demonstrated important variabilities in study methods. Four of the eight were controlled, randomized trials and four were open label.ConclusionsThese studies suggested an overall beneficial effect of epoetin alfa for treating anemia in children with cancer. Three large, multicenter clinical trials of the efficacy and safety of epoetin alfa in anemic children with cancer are currently underway, one in Europe and two in North America. Med Pediatr Oncol 2002; 39:463–468. © 2002 Wiley‐Liss, Inc.
Evaluation of segregation patterns of 21;21 Robertsonian translocation along with sex chromosomes and interchromosomal effects in sperm nuclei of carrier by FISH technique
Authors: Acar Hasan , Yildirim M. Selman , Çora Tülin , Ceylaner Serdar 
Published: September 2002

AbstractMeiotic segregation patterns of carriers of Robertsonian translocations (RT) are important for assessing the risk of unbalanced forms. We investigated the ratio of sperm with t(21;21) to sperm with nullisomy for chromosome 21; the segregation of the t(21;21) along with sex chromosomes, and also interchromosomal effects on chromosome 10 by using three color fluorescence in situ hybridization (FISH) with telomere specific (Tel 21q) and centromere‐specific alpha satellite probes for chromosomes X, Y, and 10. The percentage of cosegregation of t(21;21) with sex chromosomes (49.50%) and without sex chromosomes (46.98%) was not significant. There are no significant differences between the percentages of cosegregation of t(21;21) with chromosome X (23.36%) and with chromosome Y (26.16%). No evidence of an interchromosomal effect on chromosome 10 was detected, the percentage of chromosome 10 aneuploidy being similar to that in controls. In addition, the frequency of diploid sperm nuclei was not significantly higher in the carrier (0.32%) than in the controls (0.44%) (P > 0.05). The sex ratio was similar within the carrier and the controls and between the carrier and the control. Three color‐FISH analysis, using different probe combinations, seems a rapid and accurate tool for direct analysis of meiotic segregation product. Mol. Reprod. Dev. 63: 232–236, © 2002 Wiley‐Liss, Inc.
Control of the annual testicular cycle of the marbled‐newt by p53, p21, and Rb gene products
Authors: Ricote Monica , Alfaro Juan M. , García‐Tuñón Ignacio , Arenas M. Isabel , Fraile Benito , Paniagua Ricardo , Royuela Mar 
Published: September 2002

Abstractp53, p21, and Rb are proteins with an important role in cell‐cycle control. The expression and distribution of these gene products and the apoptotic rate were studied in the marbled‐newt testis along the annual cycle to know the role of these factors in the control of spermatogenesis and glandular tissue formation. The study was carried out using Western blot analysis and immunohistochemistry. The results differed from those, previously reported in mammals showing constant spermatogenesis. Greater expression of p53 and p21 was found in the quiescence period and was detected in PCGs (primordial germ cells), spermatogonia, follicular, interstitial cells, and glandular tissue. Greater expression of Rb and phosph‐Rb was present in the proliferation period, in PCGs, and spermatogonia. Apoptosis was only detected in secondary spermatogonia (quiescence and spermiogenesis periods) and primary spermatocytes (proliferation and spermiogenesis periods). In the quiescence period, the increase in p53 expression activates p21 expression, which inhibits Rb phosphorylation and arrests the cell cycle in G1. In the proliferation period and, in a lesser degree, in the spermiogenesis period, the expressions of p53 and p21 decrease and phosph‐Rb increases, enhancing cell proliferation. These gene products do not seem to be related to apoptosis Mol. Reprod. Dev. 63: 202–209, 2002. © 2002 Wiley‐Liss, Inc.
Expression of leukemia inhibitory factor receptor and gp130 in mouse uterus during early pregnancy
Authors: Ni Hua , Ding Nai‐Zheng , Harper Michael J.K. , Yang Zeng‐Ming 
Published: September 2002

AbstractLeukemia inhibitory factor (LIF) is essential for implantation of mouse embryos. The aim of this study was to assess the expression and regulation of LIF receptor (LIFR) and gp130 mRNA in mouse uterus during early pregnancy using in situ hybridization and reverse transcription‐polymerase chain reaction (RT‐PCR). A strong level of LIFR mRNA signal was detected in the luminal epithelium on day 5 of pregnancy. On day 6–8 of pregnancy, LIFR signal was mainly localized in the decidua. LIFR signal in the luminal epithelium of ovariectomized mouse was slightly stimulated by a combination of progesterone and estrogen. By RT‐PCR, LIFR mRNA signal was detected in all of the uteri from day 1–8 of pregnancy, being at the highest level on day 5. A low level of gp130 mRNA signal was seen in the glandular epithelium on day 3 of pregnancy and reached a high level on day 4 of pregnancy. gp130 signal in the decidua appeared on day 6 of pregnancy and reached a high level on day 7 and 8 of pregnancy. After the ovariectomized mouse was treated with a combination of progesterone and estrogen, a strong gp130 signal was observed in the glandular epithelium, while no signal was detected after progesterone or estrogen treatment alone. By RT‐PCR analysis, gp130 mRNA was detected in all of the uteri from day 1–8 of pregnancy, being at the highest level on day 4 of pregnancy. Additionally, a high level of LIFR and gp130 mRNA signal was detected in the decidua under artificial decidualization compared to the control uninjected horn. The co‐expression of a high level of LIFR and gp130 mRNA in the decidua may play a key role during the decidualization and placentation Mol. Reprod. Dev. 63: 143–150, 2002. © 2002 Wiley‐Liss, Inc.
Differential cytoplast requirement for embryonic and somatic cell nuclear transfer in cattle
Authors: Du Fuliang , Sung Li‐Ying , Tian X. Cindy , Yang Xiangzhong 
Published: September 2002

AbstractEffective activation of a recipient oocyte and its compatibility with the nuclear donor are critical to the successful nuclear reprogramming during nuclear transfer. We designed a series of experiments using various activation methods to determine the optimum activation efficiency of bovine oocytes. We then performed nuclear transfer (NT) of embryonic and somatic cells into cytoplasts presumably at G1/S phase (with prior activation) or at metaphase II (MII, without prior activation). Oocytes at 24 hr of maturation in vitro were activated with various combinations of calcium ionophore A23187 (A187) (5 μM, 5 min), electric pulse (EP), ethanol (7%, 7 min), cycloheximide (CHX) (10 μg/ml, 6 hr), and then cultured in cytochalasin D (CD) for a total of 18 hr. Through a series of experiments (Exp. 1–4), an improved activation protocol (A187/EP/CHX/CD) was identified and used for comparison of NT efficiency of embryonic versus somatic donor cells (Exp. 5). When embryonic cells from morula and blastocysts (BL) were used as nuclear donors, a significantly higher rate of blastocyst development from cloned embryos was obtained with G1/S phase cytoplasts than with MII‐phase cytoplasts (36 vs. 11%, P < 0.05). In contrast, when skin fibroblasts were used as donor cells, the use of an MII cytoplast (vs. G1/S phase) was imperative for blastocyst development (30 vs. 6%, P < 0.05). Differential staining showed that parthenogenetic, embryonic, and somatic cloned BL contained 26, 29, and 33% presumptive inner cell mass (ICM) cells, respectively, which is similar to that of frozen‐thawed in vivo embryos at a comparable developmental stage (23%). These data indicate that embryonic and somatic nuclei require different recipient cytoplast environment for remodeling/ reprogramming, and this is likely due to the different cell cycle stage and profiles of molecular differentiation of the transferred donor nuclei Mol. Reprod. Dev. 63: 183–191, 2002. © 2002 Wiley‐Liss, Inc.
Mouse transgenic for murine oviduct‐specific glycoprotein promoter‐driven simian virus 40 large T‐antigen: Tumor formation and its hormonal regulation
Authors: Miyoshi Ichiro , Takahashi Kazuhiro , Kon Yasuhiro , Okamura Tadashi , Mototani Yasumasa , Araki Yoshihiko , Kasai Noriyuki 
Published: September 2002

AbstractTransgenic mice were generated in which a 2.2‐kb segment of the 5′‐flanking sequence of the mouse oviduct‐specific glycoprotein (OGP) gene was used to drive expression of the simian virus 40 large T antigen (Tag). These mice spontaneously developed tumors in the female reproductive tract. Analysis using reverse transcriptase‐polymerase chain reaction showed that the 2.2‐kb OGP 5′‐flanking region drove Tag mRNA expression in the oviduct, uterus, vagina, and ovary, but not in other tissues. Histological and immunohistochemical analyses revealed that the tumor cells were distributed in the oviduct, endometrium, myometrium, and vagina; and had atypical features, abnormal mitosis, and Tag expression. Ovariectomy suppressed Tag expression, and thereby, blocked tumorigenesis in the transgenic mice. Estradiol administration to ovariectomized transgenic mice led to dramatic hyperplasia of the reproductive tract tissues in association with enhanced Tag expression, both in intensity and distribution. These results demonstrated that a 2.2‐kb fragment of the 5′‐flanking sequence of the mouse OGP gene was capable of directing the expression of Tag and inducing tumorigenesis in female reproductive tract tissues in an estrogen‐dependent manner. Estrogen response elements present in the promoter region were functional in vivo. These transgenic mice represent a unique model, since they develop tumors in the oviducts as well as in other tissues derived from the Mullerian duct. Mol. Reprod. Dev. 63: 168–176, 2002. © 2002 Wiley‐Liss, Inc.
Two messenger RNA isoforms of the gonadotrophin‐releasing hormone receptor, generated by alternative splicing and/or promoter usage, are differentially expressed in rainbow trout gonads during gametogenesis
Authors: Madigou Thierry , Uzbekova Svetlana , Lareyre Jean‐Jacques , Kah Olivier 
Published: September 2002

AbstractThe recent cloning of a gonadotrophin‐releasing hormone receptor (GnRH‐R) cDNA from rainbow trout showed that it contains several in‐frame ATG codons, one of which, ATG2, corresponds to that found in other species. However, an upstream codon, ATG1, could give rise to a protein with a larger extracellular domain. Using S1 nuclease assay and a method combining primer extension and RACE‐PCR, we characterized a second population of mRNA, termed mRNA‐2, with a distinct 5′untranslated region and lacking ATG1. The genomic origin of the two mRNAs was determined by establishing the complete gene structure, which shows, for the first time in a vertebrate species that an alternative splicing and promoter usage generate two GnRH‐R mRNA variants whose 5′ extremities are encoded by two different exons. The analysis of the tissue distribution indicated that mRNA‐2 presents a broader pattern of expression and is detected at higher levels than mRNA‐1. Interestingly, it was found that those two mRNAs are differentially expressed in male and female gonads during gametogenesis. In particular, the variations of mRNA‐1 levels parallel those of sGnRH expression during spermatogenesis, indicating that tissue‐specific processing of the GnRH‐R mRNA may underlie the effects of GnRH as a paracrine/autocrine regulator of gonadal functions Mol. Reprod. Dev. 63: 151–160, 2002. © 2002 Wiley‐Liss, Inc.
Position‐independent and tissue‐specific expression of porcine whey acidic protein gene from a bacterial artificial chromosome in transgenic mice
Authors: Rival‐Gervier Sylvie , Viglietta Céline , Maeder Caroline , Attal Joe , Houdebine Louis‐Marie 
Published: September 2002

AbstractSilencing of transgenes is a frequent event after the random integration of foreign DNA in the host genome following microinjection. Long genomic fragments are expected to contain all the regulatory elements necessary to induce an appropriate expression of transgenes. A bacterial artificial chromosome containing the porcine wap gene with approximately 145 and 5 kb of 5′‐ and 3′‐flanking sequences, respectively, was microinjected into fertilized mouse ovocytes. In the six transgenic lines studied, expression was strictly specific to the mammary gland of lactating animals and was position‐independent. Levels of exogenous porcine wap mRNA per copy compared favorably with the porcine wap mRNA yield in the mammary gland of a 9‐day lactating pig. These findings suggest that this insert contained most if not all of the cis‐acting elements involved in the full specific expression of the porcine wap gene. These elements constitute good candidates for directing the optimized expression of protein recombinant‐encoding genes in the mammary gland of lactating animals Mol. Reprod. Dev. 63: 161–167, 2002. © 2002 Wiley‐Liss, Inc.
Orientational dependence of T2 relaxation in articular cartilage: A microscopic MRI (μMRI) study
Authors: Xia Yang , Moody Jonathan B. , Alhadlaq Hisham 
Published: September 2002

AbstractThe experiments reported herein are the first MRI investigations of the orientational dependence of T2 relaxation in articular cartilage at microscopic resolution over the 360° angular space. For each of six canine cartilage specimens, 48 independent T2‐weighted proton images were acquired for 12 different specimen orientations. Pixel‐wise monoexponential fits of these proton images produced 12 T2 relaxation images, each with an in‐plane pixel resolution of 13.7 μm. Cartilage T2 as a function of specimen orientation was shown to follow approximately the angular dependence of the nuclear dipole–dipole interaction, with local maxima at approximately 55°, 125°, 235°, and 305°. However, the relative amplitudes of the T2 maxima deviated somewhat from those expected from the dipolar interaction. The amplitudes of these maxima also varied with tissue depth: the largest amplitudes were found in the radial zone, intermediate amplitudes were found in the superficial zone, and there was a continuous decrease in amplitude approaching the transitional zone from the superficial zone above and the radial zone below. We explain the discrepancy between the observed T2 anisotropy and the angular dependence of the dipolar interaction by means of a simple model which considers the average of one isotropic and two anisotropic spin populations—the first being associated with “free” water, and the latter two arising from collagen‐associated waters. We show that even for the “long” T2 components, which arise in multiple‐compartment studies of collagen‐water systems, there appears to be two subpopulations. Each has the same peak value of T2, but the angular dependence of one is shifted in phase by 90° relative to the other by virtue of the fact that each is associated with groups of mutually perpendicular fibrils. Magn Reson Med 48:460–469, 2002. © 2002 Wiley‐Liss, Inc.
k‐Space interpretation of the Rose Model: Noise limitation on the detectable resolution in MRI
Authors: Watts Richard , Wang Yi 
Published: September 2002

AbstractNoise limitation on the detected spatial resolution, described by the Rose Model, is well known in X‐ray imaging and routinely used in designing X‐ray imaging protocols. The purpose of this article is to revisit the Rose Model in the context of MRI where image data are acquired in the spatial frequency domain. A k‐space signal‐to‐noise ratio (kSNR) is introduced to measure the relative signal and noise powers in a circular annulus in k‐space. It is found that the kSNR diminishes rapidly with k‐space radius. The Rose criterion that the voxel SNR ∼4 is translated to kSNR cutoff values was tested using theoretical derivation and experimental histogram analysis. Experiments demonstrate that data acquisition beyond this cutoff k‐space radius adds little or no information to the image. In order to reduce the noise limit on spatial resolution, the signal strength must be improved through means such as increasing the coil sensitivity, contrast enhancement, and signal averaging. This finding implies that the optimal k‐space volume to be sampled or the optimal scan time in MRI should be matched to the relative SNR level. Magn Reson Med 48:550–554, 2002. © 2002 Wiley‐Liss, Inc.
Fluorine electron double resonance imaging for 19F MRI in low magnetic fields
Authors: Murugesan Ramachandran , English Sean , Reijnders Koen , Yamada Ken‐ichi , Cook John A. , Mitchell James B. , Subramanian Sankaran , Krishna Murali C. 
Published: September 2002

AbstractThis work demonstrates the feasibility of generating fluorine NMR images at a very low magnetic field of 0.015 T by making use of the Overhauser enhancement of 19F NMR signal brought about by a stable, water‐soluble, narrow‐line paramagnetic contrast agent. The enhancement in the 19F NMR images depends on the concentration of the single electron contrast agent, the pO2, and the electron paramagnetic resonance (EPR) irradiation power. The applicability of this technique for 19F NMR imaging is demonstrated with phantom samples, where a time resolution of 4–10 min is achieved. Proton electron double resonance imaging (PEDRI) and fluorine electron double resonance imaging (FEDRI) images were also obtained from rat kidneys ex vivo, perfused with 10 mM Oxo63 and 10 M trifluoroacetic acid. The spatial and temporal resolutions of these images are comparable to those obtained at magnetic fields 2–3 orders of magnitude larger. Constant NMR frequency (628 kHz) operation permits both FEDRI and PEDRI of identical slices without removing the object under investigation. This feasibility of coregistration of proton‐based anatomical PEDRI image with physiological FEDRI image offers good potential for studying fluorine‐containing tracers. Magn Reson Med 48:523–529, 2002. Published 2002 Wiley‐Liss, Inc.
Using UNFOLD to remove artifacts in parallel imaging and in partial‐Fourier imaging
Authors: Madore Bruno 
Published: September 2002

AbstractIn dynamic MRI, it is often difficult to achieve the acquisition speed required to resolve or freeze the temporal variations of the imaged object. Several MRI methods aim at speeding up the image acquisition process. Through assumptions and/or prior knowledge, these dynamic MRI methods allow part of the needed data to be calculated instead of acquired. For example, partial‐Fourier imaging assumes that phase varies smoothly within the object, and parallel imaging (e.g., simultaneous acquisition of spatial harmonics (SMASH) and sensitivity encoding (SENSE)) uses prior knowledge about receiver‐coil sensitivity. While these methods accelerate acquisition, they can introduce artifacts or amplify noise in doing so. The present work aims at accelerating image acquisition significantly, while introducing almost no artifacts or noise amplification. It is shown here that new, extra information is gained if dynamic MRI methods are modified so that the sampling function changes in specific ways from time‐frame to time‐frame. In other words, the set of k‐space locations that are acquired (instead of calculated) changes with time. The present temporal strategy, based on the UNaliasing by Fourier‐encoding the Overlaps in the temporaL Dimension (UNFOLD) method, can be incorporated into common dynamic MRI methods. Results with partial‐Fourier, SMASH, and SENSE imaging are presented here, where UNFOLD's contribution is to very significantly reduce the artifact and/or amplified noise content. Used in this way, UNFOLD contributes indirectly, rather than directly to the improvement in image acquisition speed, as it allows companion methods to operate properly at greater acceleration settings than would otherwise be feasible. Magn Reson Med 48:493–501, 2002. © 2002 Wiley‐Liss, Inc.
Effects of intracellular pH, blood, and tissue oxygen tension on T1ρ relaxation in rat brain
Authors: Kettunen Mikko I. , Gröhn Olli H.J. , Silvennoinen M. Johanna , Penttonen Markku , Kauppinen Risto A. 
Published: September 2002

AbstractThe effects of intracellular pH (pHi), paramagnetic macroscopic, and microscopic susceptibility on T1 in the rotating frame (T1ρ) were studied in rat brain. Intracellular acidosis was induced by hypercapnia and pHi, T1ρ, T2, diffusion, and cerebral blood volume (CBV) were quantified. Taking into account the CBV contribution, a prolongation of parenchymal T1ρ by 4.5% was ascribed to a change in tissue water relaxation caused by a one unit drop in pHi. Blood T1ρ was found to prolong linearly with blood oxygenation saturation (Y). The macroscopic susceptibility contribution to parenchymal T1ρ was assessed both through BOLD and an iron oxide contrast agent, AMI‐227. The T1ρ data from these experiments could be described by intravascular effects with insignificant effects of susceptibility gradients on tissue water. Tissue oxygen tension (PtO2) was manipulated and monitored with microelectrodes to assess its plausible contribution to microscopic susceptibility and relaxation. Parenchymal T1ρ was virtually unaffected by variations in the PtO2, but T1 was shortened in hyperoxia and T2 showed a negative BOLD effect in hypoxia. It is demonstrated that pHi directly modulates tissue T1ρ, possibly through its effect on proton exchange; however, neither BOLD nor PtO2 directly influence tissue T1ρ. The observations are discussed in the light of physicochemical mechanisms contributing to the ischemic T1ρ changes. Magn Reson Med 48:470–477, 2002. © 2002 Wiley‐Liss, Inc.