bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nuclear β‐catenin‐dependent Wnt8 signaling in vegetal cells of the early sea urchin embryo regulates gastrulation and differentiation of endoderm and mesodermal cell lineages
Authors: Wikramanayake Athula H. , Peterson Robert , Chen Jing , Huang Ling , Bince Joanna M. , McClay David R. , Klein William H. 
Published: July 2004

AbstractThe entry of β‐catenin into vegetal cell nuclei beginning at the 16‐cell stage is one of the earliest known molecular asymmetries seen along the animal–vegetal axis in the sea urchin embryo. Nuclear β‐catenin activates a vegetal signaling cascade that mediates micromere specification and specification of the endomesoderm in the remaining cells of the vegetal half of the embryo. Only a few potential target genes of nuclear β‐catenin have been functionally analyzed in the sea urchin embryo. Here, we show that SpWnt8, a Wnt8 homolog from Strongylocentrotus purpuratus, is zygotically activated specifically in 16‐cell‐stage micromeres in a nuclear β‐catenin‐dependent manner, and its expression remains restricted to the micromeres until the 60‐cell stage. At the late 60‐cell stage nuclear β‐catenin‐dependent SpWnt8 expression expands to the veg2 cell tier. SpWnt8 is the only signaling molecule thus far identified with expression localized to the 16–60‐cell stage micromeres and the veg2 tier. Overexpression of SpWnt8 by mRNA microinjection produced embryos with multiple invagination sites and showed that, consistent with its localization, SpWnt8 is a strong inducer of endoderm. Blocking SpWnt8 function using SpWnt8 morpholino antisense oligonucleotides produced embryos that formed micromeres that could transmit the early endomesoderm‐inducing signal, but these cells failed to differentiate as primary mesenchyme cells. SpWnt8‐morpholino embryos also did not form endoderm, or secondary mesenchyme‐derived pigment and muscle cells, indicating a role for SpWnt8 in gastrulation and in the differentiation of endomesodermal lineages. These results establish SpWnt8 as a critical component of the endomesoderm regulatory network in the sea urchin embryo. genesis 39:194–205, 2004. © 2004 Wiley‐Liss, Inc.
Realistic spatial sampling for MEG beamformer images
Authors: Barnes Gareth R. , Hillebrand Arjan , Fawcett Ian P. , Singh Krish D. 
Published: July 2004

AbstractThe spatial resolution achievable using magnetoencephalography (MEG) beamformer techniques is inhomogeneous across the brain and is related directly to the amplitude of the underlying electrical sources [Barnes and Hillebrand, Hum Brain Mapp 2003;18:1–12; Gross et al., Proc Natl Acad Sci USA 2001;98:694–699; Van Veen et al., IEEE Trans Biomed Eng 1997;44:867–860; Vrba and Robinson, Proc 12th Int Conf Biomagn 2001]. We set out to examine what an adequate level of spatial sampling of the brain volume is in a realistic situation, and what implications these inhomogeneities have for region‐of‐interest analysis. As a basis for these calculations, we used a simple retinotopic mapping experiment where stimuli were 17‐Hz reversing gratings presented in either left or right visual hemifield. Beamformer weights were calculated based on the covariance of the MEG data in a 0–80 Hz bandwidth. We then estimated volumetric full‐width half‐maximum (FWHM) maps at a range of sampling levels. We show that approximately 10% of the 1 mm cubic voxels in the occipital volume have a FWHM smoothness of <5 mm, and 80% <10 mm in three subjects. This was despite relatively low mean signal‐to‐noise ratios (SNR) values of 1.5. We demonstrate how visualization of these FWHM maps can be used to avoid some of the pitfalls implicit in beamformer region‐of‐interest analysis. Hum. Brain Mapping 23:120–127, 2004. © 2004 Wiley‐Liss, Inc.
Neural systems for sign language production: Mechanisms supporting lexical selection, phonological encoding, and articulation
Authors: San José‐Robertson Lucila , Corina David P. , Ackerman Debra , Guillemin Andre , Braun Allen R. 
Published: July 2004

AbstractOvert production of ASL signs was evaluated using H215O PET to differentiate brain systems that support sign language production at the lexical‐selection and phonological‐articulatory levels. Subjects were 16 right‐handed, congenitally deaf native ASL signers (10 women, six men; age 20 to 29 years). Scans were performed while subjects (1) passively viewed ASL nouns, (2) repeated nouns, (3) generated verbs in response to these nouns, (4) passively viewed videotaped segments depicting transitive actions, and (5) generated a verb to describe these actions. Conjunctions between the two verb‐generation tasks revealed left‐lateralized activation of perisylvian, frontal, and subcortical regions commonly observed in spoken language generation tasks and implicated in processes of semantic feature binding and lexical selection. Analysis of noun repetition minus viewing condition revealed activation of distinct systems supporting phonological encoding and articulation, including bilateral activation of sensorimotor areas and association cortices in the temporal, parietal, and occipital lobes. In addition, lexical‐selection and articulatory processes were associated with activation of different corticostriatal‐thalamocortical circuits: articulation with activation of the motor, and lexical‐selection with activation of the prefrontal circuits, respectively. The results collectively provide insight into dissociable neural systems underlying these psycholinguistic functions. In addition, activation of regions that are typically associated with the auditory system during sign production suggests that these regions may support modality‐independent linguistic processes, or may indicate cross‐modal plasticity within the deaf brain. Hum Brain Mapp 23:156–167, 2004. Published 2004 Wiley‐Liss, Inc.
“Aha!” effects in a guessing riddle task: An ERP study
Authors: Mai Xiao‐Qin , Luo Jing , Wu Jian‐Hui , Luo Yue‐Jia 
Published: July 2004

AbstractIn the August 2004 issue of Human Brain Mapping, it should have been noted that Drs. Yue‐Jia Luo and Jing Luo contributed equally to their ERP study of “Aha!” effects in a guessing riddle task [Hum Brain Mapp 22(4):261–270]. Correspondence should be addressed to Dr. Yue‐Jia Luo at luoyj@psych.ac.cn. Hum Brain Mapp 23:128, 2004. © 2004 Wiley‐Liss, Inc.
Effects of NQO1 deficiency on levels of cyclopurines and other oxidative DNA lesions in liver and kidney of young mice
Authors: Zhou Guo‐Dong , Randerath Kurt , Donnelly Kirby C. , Jaiswal Anil K. 
Published: July 2004

AbstractI‐compounds are bulky indigenous DNA adducts that can be detected by 32P‐postlabeling. A subgroup, termed type II I‐compounds, represents DNA lesions induced by oxidative stress. Several major type II I‐compounds have been identified as dinucleotides containing 3′‐terminal 8,5′‐cyclo‐2′‐deoxyadenosine (cA). Levels of type II I‐compounds depend on the pro‐oxidant status of the cell. For example, enhanced formation of such oxidative DNA lesions in newborn rodents appears to be a consequence of incomplete development of neonatal antioxidant defense systems. We tested the hypothesis that young mice deficient in NAD(P)H:quinone oxidoreductase 1 (NQO1), an antioxidant enzyme catalyzing the detoxification of quinones and their derivatives, show increased formation of these oxidative DNA lesions. Type II I‐compound levels were determined by 32P‐postlabeling in liver and kidney DNA of untreated male wild‐type or NQO1‐null C57BL/6 mice of different ages. NQO1 catalytic activities and contents were measured by spectrophotometric and Western blotting techniques, respectively. Elevated oxidative adduct levels including those containing cA were detected in NQO1‐null compared to wild‐type mice at 10, 30 and 90 days in liver and at 30 and 90 days in kidney DNA. Furthermore, there were statistically significant inverse relationships between type II I‐compound levels and NQO1 activities in wild‐type mice up to 30 days of age. Taken together, the results suggest that NQO1 plays an important role in attenuating endogenous oxidative DNA damage in vivo. Our results show also that type II I‐compounds represent useful and sensitive biomarkers with utility in studies of oxidative DNA damage and its consequences. © 2004 Wiley‐Liss, Inc.
The role of fibroblasts in the modulation of integrin‐dependent interactions between the gastric cell line HGT‐1 and fibronectin
Authors: Nejjari Mimoun , Anderson Wena , Pourreyron Céline , Jacquier Marie‐France , Scoazec Jean‐Yves , Remy Lionel 
Published: July 2004

AbstractFibronectin plays an important role in gastric cancer progression. However, little is known about the microenvironmental factors modulating integrin‐dependent interactions between gastric cancer cells and fibronectin. We therefore studied the regulation by fibroblasts of the integrin‐dependent adhesion and migration of the gastric cancer cell line HGT‐1 onto fibronectin. We first determined, by immunofluorescence, immunoblotting and flow cytometry, that HGT‐1 cells expressed α3, α5, α6, αV and β1 integrin chains, and the αVβ3 and αVβ5 dimers. We verified that HGT‐1 cells xenografted to the immunosuppressed newborn rat retained the integrin repertoire detected in vitro and were able to induce the formation of tumors rich in fibronectin. By using an in vitro assay in the presence of neutralizing antibodies, we verified that HGT‐1 adhesion and migration onto fibronectin involved β1, αV and α5 integrin chains; we verified, by using an in situ adhesion test to rat gastric wall frozen sections, that in situ HGT‐1 adhesion to fibronectin was integrin dependent. In coculture experiments, we showed that organ‐specific fibroblasts from stomach, lung and dermis were able to induce, in a site‐specific manner, the expression of β1, α5 and αV integrin chains in HGT‐1 cells, their integrin‐dependent adhesion and migration on fibronectin and their capacity to secrete oncofetal fibronectin. In conclusion, our results show the capacity for tissue‐derived fibroblasts to modulate the integrin‐dependent interactions between the gastric cell line HGT‐1 and fibronectin. They strongly suggest that, in gastric cancer, stromal fibroblasts contribute to promote fibronectin‐mediated local invasion by tumor cells. © 2004 Wiley‐Liss, Inc.
Potential of human γδ T lymphocytes for immunotherapy of cancer
Authors: Kabelitz Dieter , Wesch Daniela , Pitters Elke , Zöller Margot 
Published: July 2004

AbstractT lymphocytes are classified into 2 subsets based on their T‐cell receptor (TCR) expression. The vast majority of T cells expresses an αβ TCR heterodimer. These αβ T cells recognize antigenic peptides presented by MHC class I (for CD8+ T cells) or MHC class II molecules (for CD4+ T cells). Concepts of cancer immunotherapy are mostly concerned with activation of these MHC‐restricted αβ T cells. Until recently, a numerically small subset of T cells, which expresses an alternative TCR composed of a CD3‐associated γδ heterodimer, has received far less attention as a potential agent in cancer therapy. These γδ T cells share with αβ T cells certain effector functions such as cytokine production and potent cytotoxic activity but recognize different sets of antigens, usually in a non‐MHC‐restricted fashion. Different subsets of human γδ T cells recognize stress‐inducible MHC class I‐related molecules frequently expressed on epithelial tumor cells or phosphorylated metabolites which can be generated by tumor cells. In line with this, many tumor cells are highly susceptible to γδ T‐cell mediated lysis. In our article, we summarize the available evidence for a contribution of human γδ T cells in tumor defense and discuss potential strategies for the immunotherapy of tumors based on the endogenous activation and/or adoptive transfer of tumor‐reactive γδ T lymphocytes. © 2004 Wiley‐Liss, Inc.
von Hippel‐Lindau tumor suppressor protein stimulation by thrombin involves RhoA activation
Authors: Turcotte Sandra , Desrosiers Richard R. , Brand Geneviève , Béliveau Richard 
Published: July 2004

AbstractInactivation of the von Hippel‐Lindau (VHL) tumor suppressor gene is associated with the development of vascular tumors including renal cell carcinoma. Aside from the role played by the VHL protein (pVHL) in negative regulation of hypoxia‐inducible factor, 41F‐1α, pVHL also takes part in cytoskeletal organization. Thrombin is a serine protease involved in angiogenesis and in cancer progression and its action is mediated by the protease‐activated receptors (PARs). In several cell types, thrombin induces reorganization of the cytoskeleton along with RhoA activation. Thus, we conducted an investigation on the capacity of thrombin to regulate pVHL expression. Our results demonstrated that VHL mRNA and protein levels were increased by thrombin in cultured renal cancer cells. Cytoplasmic pVHL was redistributed to perinuclear regions and membrane fractions following thrombin treatments. Stimulation of Caki‐1 cells with PAR1, PAR2 and PAR4 agonist peptides demonstrated that PAR1 was the receptor involved in thrombin‐induced pVHL expression. Western blot analysis confirmed that these cells express PAR1 and that its expression was increased by thrombin. PAR1 activation by both thrombin and an agonist peptide stimulated renal cancer cell invasion through Matrigel. Interestingly, the upregulation of pVHL was dependent on RhoA because C3 exotoxin abolished pVHL induction. However, the pharmacological Rho kinase inhibitor, Y27632, did not influence pVHL expression in the presence of thrombin, suggesting that other RhoA effectors were involved in the process. Together, these results demonstrate that thrombin induces both pVHL expression via PAR1/RhoA activation as well as the stimulation of renal cancer cell invasion suggesting a role for thrombin in tumor invasion. © 2004 Wiley‐Liss, Inc.
Artificial ultraviolet radiation and ocular melanoma in Australia
Authors: Vajdic Claire M. , Kricker Anne , Giblin Michael , Mckenzie John , Aitken Joanne F. , Giles Graham G. , Armstrong Bruce K. 
Published: July 2004

AbstractWe examined risk of ocular melanoma with exposure to artificial sources of exposure to ultraviolet radiation (UVR) in a population‐based epidemiologic study of 290 cases of ocular melanoma and 893 controls aged 18–79 years in Australia in 1996–1998. Cases were identified through a prospective survey of all ophthalmologists and cancer registries in Australia; 91.8% participated. Controls were sourced from electoral rolls; 67.4% of those who were eligible and contactable participated, while 27.3% could not be contacted. Exposure to welding and use of sunlamps, including sunbeds and tanning booths, was measured by telephone interview. Analyses used unconditional logistic regression and included age, sex, region of birth, eye color, ocular and cutaneous sun sensitivity and personal sun exposure as covariates. Risk of choroid and ciliary body melanoma in 246 cases increased significantly with longer duration of use of sunlamps, first use before 21 years of age and first use after 1980. These effects were independent of personal sun exposure. Risk of these melanomas also increased with increasing duration of welding exposure, although the trend was not significant overall. There was no evidence that these exposures increased the risk of iris (n = 25) or conjunctival (n = 19) melanomas. Personal exposure to sunlamps and welding predicts risk of choroid and ciliary body melanoma in Australia. © 2004 Wiley‐Liss, Inc.
Association of lipoprotein lipase gene polymorphism with risk of prostate cancer in a japanese population
Authors: Narita Shintaro , Tsuchiya Norihiko , Wang Lizhong , Matsuura Shinobu , Ohyama Chikara , Satoh Shigeru , Sato Kazunari , Ogawa Osamu , Habuchi Tomonori , Kato Tetsuro 
Published: July 2004

AbstractA high fat intake has been associated with prostate cancer risk, and gene polymorphisms of lipoprotein lipase (LPL) play an important role in plasma lipoprotein metabolism. We herein analyzed the association of LPL gene polymorphisms with the risk of prostate cancer in a Japanese population. Three single nucleotide polymorphisms (SNPs) of LPL designated as Ser447stop, HindIII and PvuII were genotyped by the polymerase chain reaction‐restriction fragment length polymorphism method in 273 prostate cancer patients, 205 benign prostatic hyperplasia (BPH) patients and 230 male controls. The men with the CG + GG genotypes of the Ser447stop polymorphism had an increased risk of prostate cancer compared to those with the CC genotype [age‐adjusted odds ratio (aOR) = 1.625; 95% CI = 1.068–2.471; p = 0.023]. Furthermore, the increased risk associated with the CG + GG genotypes was more strongly observed in patients with high‐grade cancers (aOR = 2.843; 95% CI = 1.252–6.458; p = 0.039) or metastatic diseases (aOR = 2.300; 95% CI = 1.042–5.074; p = 0.013), whereas the risk was not significant in those with low‐ to intermediate‐grade cancers or nonmetastatic diseases. In the HindIII and PvuII polymorphisms, there was no significant difference between the prostate cancer patients and the controls, and no significant results as for tumor grade and stage. None of the 3 polymorphisms showed any association with the risk of BPH. Our results suggest that the LPL Ser447stop polymorphism is a common genetic modifier for the development of prostate cancer, particularly that of high‐grade and/or high‐stage, in a Japanese population. © 2004 Wiley‐Liss, Inc.
Type‐specific associations of human papillomavirus load with risk of developing cervical carcinoma in situ
Authors: Moberg Martin , Gustavsson Inger , Gyllensten Ulf 
Published: July 2004

AbstractWe have previously shown that high human papillomavirus (HPV) 16 load in Papanicolaou smears negative for dysplasia is strongly associated with risk for carcinoma in situ (CIS) of the cervix. Here we study the amount of HPV DNA for some of the most frequent high‐risk HPV types as determinants of progression to cervical CIS. Real‐time PCR is used to estimate the normalized viral load of HPV 16, 18, 31, 33, 35, 39, 45, 52, 58 and 67 in 457 cases of cervical CIS and 552 matched population controls. A total of 2,747 archival Pap smears from gynecologic health examinations, collected over a period of up to 26 years, were analyzed to assess viral load during the infection history. Cervical smear samples differ widely in amount of DNA, underscoring the need for normalization of HPV load to number of cells in the sample. The risk of developing cervical CIS increases with higher viral load for most of the HPV types studied. The range of copy numbers per cell does not differ between HPV types but the odds ratio for CIS in the percentile with highest viral load is substantially higher for HPV 16 (OR = 36.9; 95% CI = 8.9–153.2) than for HPV 31 (OR = 3.2; 95% CI = 1.1–9.1) or HPV 18/45 (OR = 2.6; 95% CI = 1.0–6.4). Therefore, HPV viral load may be predictive of future risk of cervical CIS at a stage when smears are negative for squamous abnormalities, but differences between HPV types need closer attention. © 2004 Wiley‐Liss, Inc.
Ethanol‐induced in vitro invasion of breast cancer cells: The contribution of MMP‐2 by fibroblasts
Authors: Aye Moe Moe , Ma Cuiling , Lin Hong , Bower Kimberly A. , Wiggins Richard C. , Luo Jia 
Published: July 2004

AbstractEthanol is a tumor promoter and may promote metastasis of breast cancer. However, the underlying cellular/molecular mechanisms remain unknown. Overexpression and high activity of matrix metalloproteinase‐2 (MMP‐2) are frequently associated with metastatic breast cancers and serve as a prognostic indicator of clinical outcome. MMP‐2 is predominantly expressed in stromal fibroblasts and plays a pivotal role in regulating the invasive behavior of breast tumor cells. We hypothesized that ethanol may enhance the invasion of breast tumor cells by modulating the activity of fibroblastic MMP‐2. With in vitro models (HS68 and CCD1056SK human fibroblasts), we showed that ethanol at physiologically relevant concentrations (50–200 mg/dl) activated MMP‐2; conversely, at a higher concentration (400 mg/dl), it inhibited the MMP‐2 activity. Consistently, conditioned medium collected from ethanol (50–200 mg/dl)‐exposed fibroblasts markedly enhanced the invasive potential of breast cancer cells and mammary epithelial cells overexpressing ErbB2/HER2 (BT474, SKBR‐3 and HB2ErbB2 cells) but had little effect on cells with low ErbB2 levels (BT20 and HB2 cells). In contrast, conditioned medium obtained from ethanol (400 mg/dl)‐treated fibroblasts inhibited cell invasion. Selective inhibitors of MMP‐2 (SB‐3CT and OA‐Hy) eliminated ethanol‐stimulated invasion, indicating that the effect of ethanol was mediated by MMP‐2. Ethanol activated conventional PKCs and JNKs in fibroblasts; inhibitors of PKC (Go6850 and Go6976) and JNKs (SP600125) significantly inhibited ethanol‐mediated MMP‐2 activation as well as cell invasion, indicating that PKCs and JNKs play a role in ethanol‐induced MMP‐2 activation and cell invasion in vitro. Thus, ethanol‐promoted breast cancer cell invasion may be mediated by the modulation of fibroblastic MMP‐2. © 2004 Wiley‐Liss, Inc.
Use of soil‐water balance components to assess yield of groundnut and sunflower under a high water table situation
Authors: Das Madhumita 
Published: July 2004

AbstractThis study aimed to evaluate the effect of water input on the yield of groundnut and sunflower grown by supplying irrigation under high water table conditions (1.2–1.75 m from the surface). Crop yield with respect to net irrigation depth and upward flux from the water table, and contribution of irrigation and groundwater to yield reveal that 4 or 6 cm water at 0.9 net irrigation (IW)/cumulative pan evaporation (CPE), and 4 or 5 cm water at 7 days interval and at 0.7 or 1.0 IW/CPE, are the suitable levels of irrigation for growing groundnut and sunflower respectively. The yield response to evapotranspiration (ET) was linear, while it was curvilinear with irrigation depth (IW). It was also curvilinear, that is quadratic, with IW in conjunction with downward drainage loss (D) in groundnut, and with D and upward flux (U) in both the crops. Consequent upon the precise estimate of predictive yield output, the functions developed for groundnut separately with ET, IW, D, IW with D, and D and U, and in sunflower, functions established by using ET or IW alone and in alliance with D and U, were found as best‐fit functions. The best‐fit functions offer some tools to be exploited for efficient utilization of irrigation water with respect to groundwater contribution towards maximum yield benefit of groundnut and sunflower grown on sandy loam to sandy clay loam Aeric Haplaquepts soil. Copyright © 2004 John Wiley & Sons, Ltd.